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Sample records for t-cell t-lymphoblastic proliferation

  1. Leukemia-Initiating Cells in T-Cell Acute Lymphoblastic Leukemia

    OpenAIRE

    Tan, Shi Hao; Bertulfo, Fatima Carla; Sanda, Takaomi

    2017-01-01

    T-cell acute lymphoblastic leukemia (T-ALL) is a hematological malignancy characterized by the clonal proliferation of immature T-cell precursors. T-ALL has many similar pathophysiological features to acute myeloid leukemia, which has been extensively studied in the establishment of the cancer stem cell (CSC) theory, but the CSC concept in T-ALL is still debatable. Although leukemia-initiating cells (LICs), which can generate leukemia in a xenograft setting, have been found in both human T-AL...

  2. miR-664 negatively regulates PLP2 and promotes cell proliferation and invasion in T-cell acute lymphoblastic leukaemia

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    Zhu, Hong; Miao, Mei-hua; Ji, Xue-qiang; Xue, Jun; Shao, Xue-jun, E-mail: xuejunshao@hotmail.com

    2015-04-03

    MicroRNAs (miRNAs) play important roles in the pathogenesis of many types of cancers by negatively regulating gene expression at posttranscriptional level. However, the role of microRNAs in leukaemia, particularly T-cell acute lymphoblastic leukaemia (T-ALL), has remained elusive. Here, we identified miR-664 and its predicted target gene PLP2 were differentially expressed in T-ALL using bioinformatics methods. In T-ALL cell lines, CCK-8 proliferation assay indicated that the cell proliferation was promoted by miR-664, while miR-664 inhibitor could significantly inhibited the proliferation. Moreover, migration and invasion assay showed that overexpression of miR-664 could significantly promoted the migration and invasion of T-ALL cells, whereas miR-664 inhibitor could reduce cell migration and invasion. luciferase assays confirmed that miR-664 directly bound to the 3'untranslated region of PLP2, and western blotting showed that miR-664 suppressed the expression of PLP2 at the protein levels. This study indicated that miR-664 negatively regulates PLP2 and promotes proliferation and invasion of T-ALL cell lines. Thus, miR-664 may represent a potential therapeutic target for T-ALL intervention. - Highlights: • miR-664 mimics promote the proliferation and invasion of T-ALL cells. • miR-664 inhibitors inhibit the proliferation and invasion of T-ALL cells. • miR-664 targets 3′ UTR of PLP2 in T-ALL cells. • miR-664 negatively regulates PLP2 in T-ALL cells.

  3. TRESK potassium channel in human T lymphoblasts

    International Nuclear Information System (INIS)

    Sánchez-Miguel, Dénison Selene; García-Dolores, Fernando; Rosa Flores-Márquez, María; Delgado-Enciso, Iván; Pottosin, Igor; Dobrovinskaya, Oxana

    2013-01-01

    Highlights: • TRESK (KCNK18) mRNA is present in different T lymphoblastic cell lines. • KCNK18 mRNA was not found in resting peripheral blood lymphocytes. • Clinical samples of T lymphoblastic leukemias and lymphomas were positive for TRESK. • TRESK in T lymphoblasts has dual localization, in plasma membrane and intracellular. -- Abstract: TRESK (TWIK-related spinal cord K + ) channel, encoded by KCNK18 gene, belongs to the double-pore domain K + channel family and in normal conditions is expressed predominantly in the central nervous system. In our previous patch-clamp study on Jurkat T lymphoblasts we have characterized highly selective K + channel with pharmacological profile identical to TRESK. In the present work, the presence of KCNK18 mRNA was confirmed in T lymphoblastic cell lines (Jurkat, JCaM, H9) but not in resting peripheral blood lymphocytes of healthy donors. Positive immunostaining for TRESK was demonstrated in lymphoblastic cell lines, in germinal centers of non-tumoral lymph nodes, and in clinical samples of T acute lymphoblastic leukemias/lymphomas. Besides detection in the plasma membrane, intracellular TRESK localization was also revealed. Possible involvement of TRESK channel in lymphocyte proliferation and tumorigenesis is discussed

  4. TRESK potassium channel in human T lymphoblasts

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    Sánchez-Miguel, Dénison Selene, E-mail: amurusk@hotmail.com [Center for Biomedical Research, University of Colima, Av. 25 de Julio 965, Villa San Sebastian, C.P. 28045 Colima (Mexico); García-Dolores, Fernando, E-mail: garciaddf@yahoo.com [Department of Pathology, Institute of Forensic Sciences, Av. Niños Héroes 130, Col. Doctores, C.P. 06720 Mexico, DF (Mexico); Rosa Flores-Márquez, María, E-mail: mariafo31@yahoo.com.mx [National Medical Center of Occident (CMNO) IMSS, Belisario Dominguez 735, Col. Independencia Oriente, C.P. 44340 Guadalajara, Jalisco (Mexico); Delgado-Enciso, Iván [University of Colima, School of Medicine, Av. Universidad 333, Col. Las Viboras, C.P. 28040 Colima (Mexico); Pottosin, Igor, E-mail: pottosin@ucol.mx [Center for Biomedical Research, University of Colima, Av. 25 de Julio 965, Villa San Sebastian, C.P. 28045 Colima (Mexico); Dobrovinskaya, Oxana, E-mail: oxana@ucol.mx [Center for Biomedical Research, University of Colima, Av. 25 de Julio 965, Villa San Sebastian, C.P. 28045 Colima (Mexico)

    2013-05-03

    Highlights: • TRESK (KCNK18) mRNA is present in different T lymphoblastic cell lines. • KCNK18 mRNA was not found in resting peripheral blood lymphocytes. • Clinical samples of T lymphoblastic leukemias and lymphomas were positive for TRESK. • TRESK in T lymphoblasts has dual localization, in plasma membrane and intracellular. -- Abstract: TRESK (TWIK-related spinal cord K{sup +}) channel, encoded by KCNK18 gene, belongs to the double-pore domain K{sup +} channel family and in normal conditions is expressed predominantly in the central nervous system. In our previous patch-clamp study on Jurkat T lymphoblasts we have characterized highly selective K{sup +} channel with pharmacological profile identical to TRESK. In the present work, the presence of KCNK18 mRNA was confirmed in T lymphoblastic cell lines (Jurkat, JCaM, H9) but not in resting peripheral blood lymphocytes of healthy donors. Positive immunostaining for TRESK was demonstrated in lymphoblastic cell lines, in germinal centers of non-tumoral lymph nodes, and in clinical samples of T acute lymphoblastic leukemias/lymphomas. Besides detection in the plasma membrane, intracellular TRESK localization was also revealed. Possible involvement of TRESK channel in lymphocyte proliferation and tumorigenesis is discussed.

  5. Leukemia-Initiating Cells in T-Cell Acute Lymphoblastic Leukemia.

    Science.gov (United States)

    Tan, Shi Hao; Bertulfo, Fatima Carla; Sanda, Takaomi

    2017-01-01

    T-cell acute lymphoblastic leukemia (T-ALL) is a hematological malignancy characterized by the clonal proliferation of immature T-cell precursors. T-ALL has many similar pathophysiological features to acute myeloid leukemia, which has been extensively studied in the establishment of the cancer stem cell (CSC) theory, but the CSC concept in T-ALL is still debatable. Although leukemia-initiating cells (LICs), which can generate leukemia in a xenograft setting, have been found in both human T-ALL patients and animal models, the nature and origin of LICs are largely unknown. In this review, we discuss recent studies on LICs in T-ALL and the potential mechanisms of LIC emergence in this disease. We focus on the oncogenic transcription factors TAL1, LMO2 , and NOTCH1 and highlight the significance of the transcriptional regulatory programs in normal hematopoietic stem cells and T-ALL.

  6. Leukemia-Initiating Cells in T-Cell Acute Lymphoblastic Leukemia

    Directory of Open Access Journals (Sweden)

    Shi Hao Tan

    2017-09-01

    Full Text Available T-cell acute lymphoblastic leukemia (T-ALL is a hematological malignancy characterized by the clonal proliferation of immature T-cell precursors. T-ALL has many similar pathophysiological features to acute myeloid leukemia, which has been extensively studied in the establishment of the cancer stem cell (CSC theory, but the CSC concept in T-ALL is still debatable. Although leukemia-initiating cells (LICs, which can generate leukemia in a xenograft setting, have been found in both human T-ALL patients and animal models, the nature and origin of LICs are largely unknown. In this review, we discuss recent studies on LICs in T-ALL and the potential mechanisms of LIC emergence in this disease. We focus on the oncogenic transcription factors TAL1, LMO2, and NOTCH1 and highlight the significance of the transcriptional regulatory programs in normal hematopoietic stem cells and T-ALL.

  7. Notch1 is required for hypoxia-induced proliferation, invasion and chemoresistance of T-cell acute lymphoblastic leukemia cells

    Directory of Open Access Journals (Sweden)

    Zou Jie

    2013-01-01

    Full Text Available Abstract Background Notch1 is a potent regulator known to play an oncogenic role in many malignancies including T-cell acute lymphoblastic leukemia (T-ALL. Tumor hypoxia and increased hypoxia-inducible factor-1α (HIF-1α activity can act as major stimuli for tumor aggressiveness and progression. Although hypoxia-mediated activation of the Notch1 pathway plays an important role in tumor cell survival and invasiveness, the interaction between HIF-1α and Notch1 has not yet been identified in T-ALL. This study was designed to investigate whether hypoxia activates Notch1 signalling through HIF-1α stabilization and to determine the contribution of hypoxia and HIF-1α to proliferation, invasion and chemoresistance in T-ALL. Methods T-ALL cell lines (Jurkat, Sup-T1 transfected with HIF-1α or Notch1 small interference RNA (siRNA were incubated in normoxic or hypoxic conditions. Their potential for proliferation and invasion was measured by WST-8 and transwell assays. Flow cytometry was used to detect apoptosis and assess cell cycle regulation. Expression and regulation of components of the HIF-1α and Notch1 pathways and of genes related to proliferation, invasion and apoptosis were assessed by quantitative real-time PCR or Western blot. Results Hypoxia potentiated Notch1 signalling via stabilization and activation of the transcription factor HIF-1α. Hypoxia/HIF-1α-activated Notch1 signalling altered expression of cell cycle regulatory proteins and accelerated cell proliferation. Hypoxia-induced Notch1 activation increased the expression of matrix metalloproteinase-2 (MMP2 and MMP9, which increased invasiveness. Of greater clinical significance, knockdown of Notch1 prevented the protective effect of hypoxia/HIF-1α against dexamethasone-induced apoptosis. This sensitization correlated with losing the effect of hypoxia/HIF-1α on Bcl-2 and Bcl-xL expression. Conclusions Notch1 signalling is required for hypoxia/HIF-1α-induced proliferation

  8. Immature MEF2C-dysregulated T-cell leukemia patients have an early T-cell precursor acute lymphoblastic leukemia gene signature and typically have non-rearranged T-cell receptors

    Science.gov (United States)

    Zuurbier, Linda; Gutierrez, Alejandro; Mullighan, Charles G.; Canté-Barrett, Kirsten; Gevaert, A. Olivier; de Rooi, Johan; Li, Yunlei; Smits, Willem K.; Buijs-Gladdines, Jessica G.C.A.M.; Sonneveld, Edwin; Look, A. Thomas; Horstmann, Martin; Pieters, Rob; Meijerink, Jules P.P.

    2014-01-01

    Three distinct immature T-cell acute lymphoblastic leukemia entities have been described including cases that express an early T-cell precursor immunophenotype or expression profile, immature MEF2C-dysregulated T-cell acute lymphoblastic leukemia cluster cases based on gene expression analysis (immature cluster) and cases that retain non-rearranged TRG@ loci. Early T-cell precursor acute lymphoblastic leukemia cases exclusively overlap with immature cluster samples based on the expression of early T-cell precursor acute lymphoblastic leukemia signature genes, indicating that both are featuring a single disease entity. Patients lacking TRG@ rearrangements represent only 40% of immature cluster cases, but no further evidence was found to suggest that cases with absence of bi-allelic TRG@ deletions reflect a distinct and even more immature disease entity. Immature cluster/early T-cell precursor acute lymphoblastic leukemia cases are strongly enriched for genes expressed in hematopoietic stem cells as well as genes expressed in normal early thymocyte progenitor or double negative-2A T-cell subsets. Identification of early T-cell precursor acute lymphoblastic leukemia cases solely by defined immunophenotypic criteria strongly underestimates the number of cases that have a corresponding gene signature. However, early T-cell precursor acute lymphoblastic leukemia samples correlate best with a CD1 negative, CD4 and CD8 double negative immunophenotype with expression of CD34 and/or myeloid markers CD13 or CD33. Unlike various other studies, immature cluster/early T-cell precursor acute lymphoblastic leukemia patients treated on the COALL-97 protocol did not have an overall inferior outcome, and demonstrated equal sensitivity levels to most conventional therapeutic drugs compared to other pediatric T-cell acute lymphoblastic leukemia patients. PMID:23975177

  9. MicroRNA-101 regulates T-cell acute lymphoblastic leukemia progression and chemotherapeutic sensitivity by targeting Notch1.

    Science.gov (United States)

    Qian, Lu; Zhang, Wanggang; Lei, Bo; He, Aili; Ye, Lianhong; Li, Xingzhou; Dong, Xin

    2016-11-01

    The present study aimed to investigate the role of microRNA (miR)-101 in acute lymphoblastic leukemia progression and chemoresistance. Furthermore, a novel target gene of miR-101 was identified. Here, we confirmed that miR-101 was significantly downregulated in the blood samples of patients with T-cell acute lymphoblastic leukemia (T-ALL) compared with the healthy controls, as determined by reverse transcription quantitative polymerase chain reaction (RTqPCR) analysis. The in vitro experiments demonstrated that miR-101 significantly repressed the proliferation and invasion, and induced potent apoptosis in Jurkat cells, as determined by CCK-8, flow cytometer and cell invasion assays. Luciferase assay confirmed that Notch1 was a target gene of miR-101, and western blotting showed that miR-101 suppressed the expression of Notch1 at the protein level. Moreover, functional restoration assays revealed that Notch1 mediates the effects of miR-101 on Jurkat cell proliferation, apoptosis and invasion. miR-101 enhanced the sensitivity of Jurkat cells to the chemotherapeutic agent adriamycin. Taken together, our results show for the first time that miR-101 acts as a tumor suppressor in T-cell acute lymphoblastic leukaemia and it could enhance chemotherapeutic sensitivity. Furthermore, Notch1 was identified to be a novel target of miR-101. This study indicates that miR-101 may represent a potential therapeutic target for T-cell acute lymphoblastic leukemia intervention.

  10. Rapid progression of mediastinal tumor within a few days: A case report of T cell lymphoblastic lymphoma

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    Ahn, Tae Ran; Lee, Young Kyung; Jun, Hyun Jung; Jung, Eun Ah; Son, Jin Sung [Seoul Medical Center, Seoul (Korea, Republic of)

    2016-05-15

    T-cell lymphoblastic lymphoma is a highly aggressive tumor derived from lymphocyte of the thymus, which accounts for 2% of non-Hodgkin's lymphoma. The disease occurs most commonly in adolescent and young adult males. It often results in respiratory emergency because of high proliferation rate. In this case, we confirmed the rapid progression of T-cell lymphoblastic lymphoma through the chest CT scan with one week interval. Three days of empirical chemotherapy resulted in substantial reduction of mediastinal mass, pleural thickening and pleural effusion.

  11. A novel 2,6-diisopropylphenyl-docosahexaenoamide conjugate induces apoptosis in T cell acute lymphoblastic leukemia cell lines

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    Altenburg, Jeffrey D.; Harvey, Kevin A.; McCray, Sharon; Xu, Zhidong [Cellular Biochemistry Laboratory, Methodist Research Institute, Indiana University Health, Indianapolis, IN (United States); Siddiqui, Rafat A., E-mail: rsiddiqu@iuhealth.org [Cellular Biochemistry Laboratory, Methodist Research Institute, Indiana University Health, Indianapolis, IN (United States); Department of Biology, Indiana University-Purdue University, Indianapolis, IN (United States); Department of Medicine, Indiana University School of Medicine, Indianapolis, IN (United States)

    2011-07-29

    Highlights: {yields} 2,6-Diisopropylphenyl-docosahexaenoamide conjugates (DIP-DHA) inhibits the proliferation of T-cell leukemic cell lines. {yields} DIP-DHA resulted in increased activation of caspase-3, and caspase-7. {yields} DIP-DHA significantly downregulated CXCR4 surface expression. -- Abstract: We have previously characterized the effects of 2,6-diisopropylphenyl-docosahexaenoamide (DIP-DHA) conjugates and their analogs on the proliferation and progression of breast cancer cell lines. For this study, we investigated the effects of the DIP-DHA conjugate on 2 representative T cell acute lymphoblastic leukemia (T-ALL) cell lines: CEM and Jurkat. Treatment of both cell lines with DIP-DHA resulted in significantly greater inhibition of proliferation and induction of apoptosis than that of parent compounds, 2,6-diisopropylphenol (DIP) or docosahexaenoate (DHA). Treatment of the cells with DIP-DHA resulted in increased activation of caspase-3, and caspase-7. Furthermore, induction of apoptosis in both cell lines was reversed in the presence of a caspase family inhibitor. Treatment with DIP-DHA reduced mitochondrial membrane potential. These observations suggest that the effects are driven by intrinsic apoptotic pathways. DIP-DHA treatment also downregulated surface CXCR4 expression, an important chemokine receptor involved in cancer metastasis that is highly expressed in both CEM and Jurkat cells. In conclusion, our data suggest that the DIP-DHA conjugate exhibits significantly more potent effects on CEM and Jurkat cells than that of DIP or DHA alone. These conjugates have potential use for treatment of patients with T cell acute lymphoblastic leukemia.

  12. A novel 2,6-diisopropylphenyl-docosahexaenoamide conjugate induces apoptosis in T cell acute lymphoblastic leukemia cell lines

    International Nuclear Information System (INIS)

    Altenburg, Jeffrey D.; Harvey, Kevin A.; McCray, Sharon; Xu, Zhidong; Siddiqui, Rafat A.

    2011-01-01

    Highlights: → 2,6-Diisopropylphenyl-docosahexaenoamide conjugates (DIP-DHA) inhibits the proliferation of T-cell leukemic cell lines. → DIP-DHA resulted in increased activation of caspase-3, and caspase-7. → DIP-DHA significantly downregulated CXCR4 surface expression. -- Abstract: We have previously characterized the effects of 2,6-diisopropylphenyl-docosahexaenoamide (DIP-DHA) conjugates and their analogs on the proliferation and progression of breast cancer cell lines. For this study, we investigated the effects of the DIP-DHA conjugate on 2 representative T cell acute lymphoblastic leukemia (T-ALL) cell lines: CEM and Jurkat. Treatment of both cell lines with DIP-DHA resulted in significantly greater inhibition of proliferation and induction of apoptosis than that of parent compounds, 2,6-diisopropylphenol (DIP) or docosahexaenoate (DHA). Treatment of the cells with DIP-DHA resulted in increased activation of caspase-3, and caspase-7. Furthermore, induction of apoptosis in both cell lines was reversed in the presence of a caspase family inhibitor. Treatment with DIP-DHA reduced mitochondrial membrane potential. These observations suggest that the effects are driven by intrinsic apoptotic pathways. DIP-DHA treatment also downregulated surface CXCR4 expression, an important chemokine receptor involved in cancer metastasis that is highly expressed in both CEM and Jurkat cells. In conclusion, our data suggest that the DIP-DHA conjugate exhibits significantly more potent effects on CEM and Jurkat cells than that of DIP or DHA alone. These conjugates have potential use for treatment of patients with T cell acute lymphoblastic leukemia.

  13. Profound radiosensitivity in leukemic T-cell lines and T-cell-type acute lymphoblastic leukemia demonstrated by sodium [51Cr]chromate labeling

    International Nuclear Information System (INIS)

    Nakazawa, S.; Minowada, J.; Tsubota, T.; Sinks, L.F.

    1978-01-01

    Radiation sensitivity was determined by measuring spontaneous release from 51 Cr-labeled cells in various lymphoid cell populations. Among six leukemia T-cell lines originating from acute lymphoblastic leukemia, four such lines were found to be highly radiosensitive. In contrast, two of the leukemic T-cell lines and four normal control B-cell lines were not radiosensitive. Thymocytes from six patients and leukemia T-cell blasts from three patients with T-cell leukemia were likewise found to be highly radiosensitive, whereas leukemic blasts from six patients with null-cell (non-T, non-B-cell) acute lymphoblastic leukemia were not radiosensitive. Normal peripheral blood lymphocytes and mitogen-induced normal lymphoblasts were found not to be radiosensitive. The results indicate that measurement of the radiation sensitivity of acute leukemic blasts may have a therapeutic significance in coping with the heterogeneous nature of individual leukemia cases

  14. Primary orbital precursor T-cell lymphoblastic lymphoma

    DEFF Research Database (Denmark)

    Stenman, Lisa; Persson, Marta; Enlund, Fredrik

    2016-01-01

    Primary T-cell lymphoblastic lymphoma (T-LBL) in the eye region is very rare. The present study described a unique case of T-LBL involving the extraocular muscles. A 22-year-old male patient presented with a 3-week history of headache, reduced visual acuity and edema of the left eye. Clinical...... knowledge, this is the first report of a case of T-LBL involving the extraocular muscles. Although primary T-LBL in the eye region is very rare, our findings demonstrate that lymphoma should be considered in the differential diagnosis of patients with similar symptoms....

  15. PHF6 mutations in T-cell acute lymphoblastic leukemia

    NARCIS (Netherlands)

    P. van Vlierberghe (Pieter); T. Palomero (Teresa); H. Khiabanian (Hossein); J. van der Meulen (Joni); M. Castillo (Mireia); N. van Roy (Nadine); B. de Moerloose (Barbara); J. Philippé (Jan); S. González-García (Sara); M.L. Toribio (María); T. Taghon (Tom); L.C. Zuurbier (Linda); B. Cauwelier (Barbara); C.J. Harrison (Christine); C. Schwab (Claire); M. Pisecker (Markus); S. Strehl; A.W. Langerak (Anton); J. Gecz (Jozef); E. Sonneveld (Edwin); R. Pieters (Rob); E. Paietta (Elisabeth); J. Rowe (Jacob); P.H. Wiernik (Peter); Y. Benoit (Yves); J. Soulier (Jean); B. Poppe (Bruce); X. Yao (Xiaopan); C. Cordon-Cardo (Carlos); J.P.P. Meijerink (Jules); R. Rabadan (Raul); F. Speleman (Franki); A.A. Ferrando (Adolfo)

    2010-01-01

    textabstractTumor suppressor genes on the X chromosome may skew the gender distribution of specific types of cancer. T-cell acute lymphoblastic leukemia (T-ALL) is an aggressive hematological malignancy with an increased incidence in males. In this study, we report the identification of inactivating

  16. Aberrant Signaling Pathways in T-Cell Acute Lymphoblastic Leukemia

    Science.gov (United States)

    Bongiovanni, Deborah; Saccomani, Valentina

    2017-01-01

    T-cell acute lymphoblastic leukemia (T-ALL) is an aggressive disease caused by the malignant transformation of immature progenitors primed towards T-cell development. Clinically, T-ALL patients present with diffuse infiltration of the bone marrow by immature T-cell blasts high blood cell counts, mediastinal involvement, and diffusion to the central nervous system. In the past decade, the genomic landscape of T-ALL has been the target of intense research. The identification of specific genomic alterations has contributed to identify strong oncogenic drivers and signaling pathways regulating leukemia growth. Notwithstanding, T-ALL patients are still treated with high-dose multiagent chemotherapy, potentially exposing these patients to considerable acute and long-term side effects. This review summarizes recent advances in our understanding of the signaling pathways relevant for the pathogenesis of T-ALL and the opportunities offered for targeted therapy. PMID:28872614

  17. Peripheral T-lymphocytes express WNT7A and its restoration in leukemia-derived lymphoblasts inhibits cell proliferation

    International Nuclear Information System (INIS)

    Ochoa-Hernández, Alejandra B; Bravo-Cuellar, Alejandro; Jave-Suarez, Luis F; Barros-Núñez, Patricio; Aguilar-Lemarroy, Adriana; Ramos-Solano, Moisés; Meza-Canales, Ivan D; García-Castro, Beatriz; Rosales-Reynoso, Mónica A; Rosales-Aviña, Judith A; Barrera-Chairez, Esperanza; Ortíz-Lazareno, Pablo C; Hernández-Flores, Georgina

    2012-01-01

    WNT7a, a member of the Wnt ligand family implicated in several developmental processes, has also been reported to be dysregulated in some types of tumors; however, its function and implication in oncogenesis is poorly understood. Moreover, the expression of this gene and the role that it plays in the biology of blood cells remains unclear. In addition to determining the expression of the WNT7A gene in blood cells, in leukemia-derived cell lines, and in samples of patients with leukemia, the aim of this study was to seek the effect of this gene in proliferation. We analyzed peripheral blood mononuclear cells, sorted CD3 and CD19 cells, four leukemia-derived cell lines, and blood samples from 14 patients with Acute lymphoblastic leukemia (ALL), and 19 clinically healthy subjects. Reverse transcription followed by quantitative Real-time Polymerase chain reaction (qRT-PCR) analysis were performed to determine relative WNT7A expression. Restoration of WNT7a was done employing a lentiviral system and by using a recombinant human protein. Cell proliferation was measured by addition of WST-1 to cell cultures. WNT7a is mainly produced by CD3 T-lymphocytes, its expression decreases upon activation, and it is severely reduced in leukemia-derived cell lines, as well as in the blood samples of patients with ALL when compared with healthy controls (p ≤0.001). By restoring WNT7A expression in leukemia-derived cells, we were able to demonstrate that WNT7a inhibits cell growth. A similar effect was observed when a recombinant human WNT7a protein was used. Interestingly, restoration of WNT7A expression in Jurkat cells did not activate the canonical Wnt/β-catenin pathway. To our knowledge, this is the first report evidencing quantitatively decreased WNT7A levels in leukemia-derived cells and that WNT7A restoration in T-lymphocytes inhibits cell proliferation. In addition, our results also support the possible function of WNT7A as a tumor suppressor gene as well as a therapeutic

  18. CD90 and CD110 correlate with cancer stem cell potentials in human T-acute lymphoblastic leukemia cells

    International Nuclear Information System (INIS)

    Yamazaki, Hiroto; Nishida, Hiroko; Iwata, Satoshi; Dang, Nam H.; Morimoto, Chikao

    2009-01-01

    Although cancer stem cells (CSCs) have been recently identified in myeloid leukemia, published data on lymphoid malignancy have been sparse. T-acute lymphoblastic leukemia (T-ALL) is characterized by the abnormal proliferation of T-cell precursors and is generally aggressive. As CD34 is the only positive-selection marker for CSCs in T-ALL, we performed extensive analysis of CD markers in T-ALL cell lines. We found that some of the tested lines consisted of heterogeneous populations of cells with various levels of surface marker expression. In particular, a small subpopulation of CD90 (Thy-1) and CD110 (c-Mpl) were shown to correlate with stem cell properties both in vitro and in transplantation experiments. As these markers are expressed on hematopoietic stem cells, our results suggest that stem cell-like population are enriched in CD90+/CD110+ fraction and they are useful positive-selection markers for the isolation of CSCs in some cases of T-ALL.

  19. CD90 and CD110 correlate with cancer stem cell potentials in human T-acute lymphoblastic leukemia cells

    Energy Technology Data Exchange (ETDEWEB)

    Yamazaki, Hiroto; Nishida, Hiroko; Iwata, Satoshi [Division of Clinical Immunology, Advanced Clinical Research Center, Institute of Medical Science, University of Tokyo, Tokyo 108-8639 (Japan); Dang, Nam H. [Department of Hematologic Malignancies, Nevada Cancer Institute, Las Vegas, NV (United States); Morimoto, Chikao, E-mail: morimoto@ims.u-tokyo.ac.jp [Division of Clinical Immunology, Advanced Clinical Research Center, Institute of Medical Science, University of Tokyo, Tokyo 108-8639 (Japan)

    2009-05-29

    Although cancer stem cells (CSCs) have been recently identified in myeloid leukemia, published data on lymphoid malignancy have been sparse. T-acute lymphoblastic leukemia (T-ALL) is characterized by the abnormal proliferation of T-cell precursors and is generally aggressive. As CD34 is the only positive-selection marker for CSCs in T-ALL, we performed extensive analysis of CD markers in T-ALL cell lines. We found that some of the tested lines consisted of heterogeneous populations of cells with various levels of surface marker expression. In particular, a small subpopulation of CD90 (Thy-1) and CD110 (c-Mpl) were shown to correlate with stem cell properties both in vitro and in transplantation experiments. As these markers are expressed on hematopoietic stem cells, our results suggest that stem cell-like population are enriched in CD90+/CD110+ fraction and they are useful positive-selection markers for the isolation of CSCs in some cases of T-ALL.

  20. Effects of valproic acid and pioglitazone on cell cycle progression and proliferation of T-cell acute lymphoblastic leukemia Jurkat cells

    Directory of Open Access Journals (Sweden)

    Marie Saghaeian Jazi

    2016-07-01

    Full Text Available Objective(s: T-cell acute lymphoblastic leukemia (T-ALL is an aggressive hematologic malignant tumor. Administration of chemical compounds influencing apoptosis and T cell development has been discussed as promising novel therapeutic strategies. Valproic acid (VPA as a recently emerged anti-neoplastic histone deacetylase (HDAC inhibitor and pioglitazone (PGZ as a high-affinity peroxisome proliferator-activated receptor-gamma (PPARγ agonist have been shown to induce apoptosis and cell cycle arrest in different studies. Here, we aimed to investigate the underlying molecular mechanisms involved in anti-proliferative effects of these compounds on human Jurkat cells. Materials and Methods: Treated cells were evaluated for cell cycle progression and apoptosis using flowcytometry and MTT viability assay. Real-time RT-PCR was carried out to measure the alterations in key genes associated with cell death and cell cycle arrest. Results: Our findings illustrated that both VPA and PGZ can inhibit Jurkat E6.1 cells in vitro after   24 hr; however, PGZ 400 μM presents the most anti-proliferative effect. Interestingly, treated cells have been arrested in G2/M with deregulated cell division cycle 25A (Cdc25A phosphatase and cyclin-dependent kinase inhibitor 1B (CDKN1B or p27 expression. Expression of cyclin D1 gene was inhibited when DNA synthesis entry was declined. Cell cycle deregulation in PGZ and VPA-exposed cells generated an increase in the proportion of aneuploid cell population, which has not reported before. Conclusion: These findings define that anti-proliferative effects of PGZ and VPA on Jurkat cell line are mediated by cell cycle deregulation. Thus, we suggest PGZ and VPA may relieve potential therapeutic application against apoptosis-resistant malignancies.

  1. Chimeric Antigen Receptor T-Cells for the Treatment of B-Cell Acute Lymphoblastic Leukemia

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    Ciprian Tomuleasa

    2018-02-01

    Full Text Available Chimeric antigen receptor (CAR T-cell technology has seen a rapid development over the last decade mostly due to the potential that these cells may have in treating malignant diseases. It is a generally accepted principle that very few therapeutic compounds deliver a clinical response without treatment-related toxicity, and studies have shown that CAR T-cells are not an exception to this rule. While large multinational drug companies are currently investigating the potential role of CAR T-cells in hematological oncology, the potential of such cellular therapies are being recognized worldwide as they are expected to expand in the patient to support the establishment of the immune memory, provide a continuous surveillance to prevent and/or treat a relapse, and keep the targeted malignant cell subpopulation in check. In this article, we present the possible advantages of using CAR T-cells in treating acute lymphoblastic leukemia, presenting the technology and the current knowledge in their preclinical and early clinical trial use. Thus, this article first presents the main present-day knowledge on the standard of care for acute lymphoblastic leukemia. Afterward, current knowledge is presented about the use of CAR T-cells in cancer immunotherapy, describing their design, the molecular constructs, and the preclinical data on murine models to properly explain the background for their clinical use. Last, but certainly not least, this article presents the use of CAR T-cells for the immunotherapy of B-cell acute lymphoblastic leukemia, describing both their potential clinical advantages and the possible side effects.

  2. TAL1/SCL is downregulated upon histone deacetylase inhibition in T-cell acute lymphoblastic leukemia cells

    NARCIS (Netherlands)

    Cardoso, B. A.; de Almeida, S. F.; Laranjeira, A. B. A.; Carmo-Fonseca, M.; Yunes, J. A.; Coffer, P. J.; Barata, J. T.

    2011-01-01

    The transcription factor T-cell acute lymphocytic leukemia (TAL)-1 is a major T-cell oncogene associated with poor prognosis in T-cell acute lymphoblastic leukemia (T-ALL). TAL1 binds histone deacetylase 1 and incubation with histone deacetylase inhibitors (HDACis) promotes apoptosis of leukemia

  3. RUNX1 promotes cell growth in human T-cell acute lymphoblastic leukemia by transcriptional regulation of key target genes.

    Science.gov (United States)

    Jenkins, Catherine E; Gusscott, Samuel; Wong, Rachel J; Shevchuk, Olena O; Rana, Gurneet; Giambra, Vincenzo; Tyshchenko, Kateryna; Islam, Rashedul; Hirst, Martin; Weng, Andrew P

    2018-05-04

    RUNX1 is frequently mutated in T-cell acute lymphoblastic leukemia (T-ALL). The spectrum of RUNX1 mutations has led to the notion that it acts as a tumor suppressor in this context; however, other studies have placed RUNX1 along with transcription factors TAL1 and NOTCH1 as core drivers of an oncogenic transcriptional program. To reconcile these divergent roles, we knocked down RUNX1 in human T-ALL cell lines and deleted Runx1 or Cbfb in primary mouse T-cell leukemias. RUNX1 depletion consistently resulted in reduced cell proliferation and increased apoptosis. RUNX1 upregulated variable sets of target genes in each cell line, but consistently included a core set of oncogenic effectors including IGF1R and NRAS. Our results support the conclusion that RUNX1 has a net positive effect on cell growth in the context of established T-ALL. Copyright © 2018. Published by Elsevier Inc.

  4. T cell differentiation stages identified by molecular and immunologic analysis of the T cell receptor complex in childhood lymphoblastic leukemia.

    Science.gov (United States)

    Mirro, J; Kitchingman, G; Behm, F G; Murphy, S B; Goorha, R M

    1987-03-01

    T cell differentiation was investigated by determining the relationship of T cell receptor (Ti) gene rearrangement and transcription to the expression of surface and cytoplasmic T3 antigen using blast cells from five children with acute lymphoblastic leukemia of thymic origin. Patterns of monoclonal antibody (MoAb) reactivity indicated that these cases were representative of the three recognized stages (I, II, III) of human thymocyte development. The T3 antigen, which becomes linked to the Ti to form a functional T cell receptor complex on mature thymocytes, was expressed on the cell surface in two cases (stage III). However, in the remaining three cases that were surface T3 negative (stages I and II), large amounts of T3 were identified in the cytoplasm by immunoperoxidase staining and flow cytometry. Leukemic blasts from all five patients showed rearranged genes encoding the beta-chain portion of the Ti heterodimer. RNA transcripts of Ti beta-chain genes were also evident in lymphoblasts from all five cases, but transcripts coding for the alpha-chain portion of Ti were found only in cases that expressed T3 on the cell surface. Thus the absence of surface T3 (and presumably Ti) coincides with the absence of Ti alpha-chain RNA, suggesting that transcription of alpha-chain genes is a critical regulatory event in the surface expression of the Ti-T3 complex. Leukemic T cells that rearrange and express Ti beta-chain genes but lack Ti alpha-chain messenger RNA (mRNA) may represent a stage of differentiation analogous to pre-B cells, where heavy-chain immunoglobulin (Ig) genes are rearranged and expressed but light-chain Ig genes are not expressed.

  5. Primary orbital precursor T-cell lymphoblastic lymphoma

    DEFF Research Database (Denmark)

    Stenman, Lisa; Persson, Marta; Enlund, Fredrik

    2016-01-01

    Primary T-cell lymphoblastic lymphoma (T-LBL) in the eye region is very rare. The present study described a unique case of T-LBL involving the extraocular muscles. A 22-year-old male patient presented with a 3-week history of headache, reduced visual acuity and edema of the left eye. Clinical...... examination revealed left-sided exophthalmus, periorbital edema, chemosis, and reduced motility of the left eye. A magnetic resonance imaging scan revealed thickening of the left orbital muscles and a positron emission tomography-computed tomography scan also demonstrated activity in a subclavicular lymph....... There was no involvement of the bone marrow. Based on the clinical and histopathological findings, a diagnosis of T-LBL was made. There was no evidence of NOTCH1 mutation or rearrangements of the ETV6 and MLL genes and high-resolution array-based comparative genomic hybridization (arrayCGH) analysis revealed a normal...

  6. TLX1 and NOTCH coregulate transcription in T cell acute lymphoblastic leukemia cells

    OpenAIRE

    Riz, Irene; Hawley, Teresa S; Luu, Truong V; Lee, Norman H; Hawley, Robert G

    2010-01-01

    Abstract Background The homeobox gene TLX1 (for T-cell leukemia homeobox 1, previously known as HOX11) is inappropriately expressed in a major subgroup of T cell acute lymphoblastic leukemia (T-ALL) where it is strongly associated with activating NOTCH1 mutations. Despite the recognition that these genetic lesions cooperate in leukemogenesis, there have been no mechanistic studies addressing how TLX1 and NOTCH1 functionally interact to promote the leukemic phenotype. Results Global gene expre...

  7. Deletions of the long arm of chromosome 5 define subgroups of T-cell acute lymphoblastic leukemia.

    Science.gov (United States)

    La Starza, Roberta; Barba, Gianluca; Demeyer, Sofie; Pierini, Valentina; Di Giacomo, Danika; Gianfelici, Valentina; Schwab, Claire; Matteucci, Caterina; Vicente, Carmen; Cools, Jan; Messina, Monica; Crescenzi, Barbara; Chiaretti, Sabina; Foà, Robin; Basso, Giuseppe; Harrison, Christine J; Mecucci, Cristina

    2016-08-01

    Recurrent deletions of the long arm of chromosome 5 were detected in 23/200 cases of T-cell acute lymphoblastic leukemia. Genomic studies identified two types of deletions: interstitial and terminal. Interstitial 5q deletions, found in five cases, were present in both adults and children with a female predominance (chi-square, P=0.012). Interestingly, these cases resembled immature/early T-cell precursor acute lymphoblastic leukemia showing significant down-regulation of five out of the ten top differentially expressed genes in this leukemia group, including TCF7 which maps within the 5q31 common deleted region. Mutations of genes known to be associated with immature/early T-cell precursor acute lymphoblastic leukemia, i.e. WT1, ETV6, JAK1, JAK3, and RUNX1, were present, while CDKN2A/B deletions/mutations were never detected. All patients had relapsed/resistant disease and blasts showed an early differentiation arrest with expression of myeloid markers. Terminal 5q deletions, found in 18 of patients, were more prevalent in adults (chi-square, P=0.010) and defined a subgroup of HOXA-positive T-cell acute lymphoblastic leukemia characterized by 130 up- and 197 down-regulated genes. Down-regulated genes included TRIM41, ZFP62, MAPK9, MGAT1, and CNOT6, all mapping within the 1.4 Mb common deleted region at 5q35.3. Of interest, besides CNOT6 down-regulation, these cases also showed low BTG1 expression and a high incidence of CNOT3 mutations, suggesting that the CCR4-NOT complex plays a crucial role in the pathogenesis of HOXA-positive T-cell acute lymphoblastic leukemia with terminal 5q deletions. In conclusion, interstitial and terminal 5q deletions are recurrent genomic losses identifying distinct subtypes of T-cell acute lymphoblastic leukemia. Copyright© Ferrata Storti Foundation.

  8. Potential for bispecific T-cell engagers: role of blinatumomab in acute lymphoblastic leukemia

    Directory of Open Access Journals (Sweden)

    Le Jeune C

    2016-02-01

    Full Text Available Caroline Le Jeune, Xavier Thomas Hospices Civils de Lyon, Hematology Department, Lyon-Sud Hospital, Pierre Bénite, France Abstract: Patients with relapsed/refractory (R/R B-precursor acute lymphoblastic leukemia (ALL and patients whose minimal residual disease persists during treatment have a poor leukemia-free survival. Despite improvements in front-line therapy, the outcome in these patients remains poor, especially after relapse. As there are no standard chemotherapeutic regimens for the treatment of patients with R/R B-precursor ALL, T-cell-based therapeutic approaches have recently come to the forefront in ALL therapy. Recently, monoclonal antibodies have been developed to target specific antigens expressed in B-lineage blast cells. In this setting, CD19 is of great interest as this antigen is expressed in B-lineage cells. Therefore, it has been selected as the target antigen for blinatumomab, a new bi-specific T-cell engager antibody. This sophisticated antibody binds sites for both CD19 and CD3, leading to T-cell proliferation and activation and B-cell apoptosis. Owing to its short serum half-life, blinatumomab has been administrated by continuous intravenous infusion with a favorable safety profile. The most significant toxicities were central nervous system events and the cytokine release syndrome. This new therapeutic approach using blinatumomab has been shown to be effective in patients with positive minimal residual disease and in patients with R/R B-precursor ALL leading to a recent approval by the US Food and Drug Administration after an accelerated review process. This review focuses on the profile of blinatumomab and its efficacy and safety. Keywords: B-cell lineage acute lymphoblastic leukemia, relapsed/refractory, minimal residual disease, BiTE monoclonal antibodies, blinatumomab

  9. Plumbagin exerts an immunosuppressive effect on human T-cell acute lymphoblastic leukemia MOLT-4 cells

    Energy Technology Data Exchange (ETDEWEB)

    Bae, Kyoung Jun; Lee, Yura [Department of Biomedical Laboratory Science, Daejeon 34824 (Korea, Republic of); Kim, Soon Ae [Department of Pharmacology, School of Medicine, Daejeon 34824 (Korea, Republic of); Kim, Jiyeon, E-mail: yeon@eulji.ac.kr [Department of Biomedical Laboratory Science, Daejeon 34824 (Korea, Republic of)

    2016-04-22

    Of the hematological disorders typified by poor prognoses and survival rates, T-cell acute lymphoblastic leukemia (T-ALL) is one of the most commonly diagnosed. Despite the development of new therapeutic agents, the treatment options for this cancer remain limited. In this manuscript, we investigated the anti-proliferative effects of plumbagin, mediated by the activation of mitogen-activated protein kinase (MAPK) pathways, and inhibition of NF-κB signaling; the human T-ALL MOLT-4 cell line was used as our experimental system. Plumbagin is a natural, plant derived compound, which exerts an anti-proliferative activity against many types of human cancer. Our experiments confirm that plumbagin induces a caspase-dependent apoptosis of MOLT-4 cells, with no significant cytotoxicity seen for normal peripheral blood mononuclear cells (PBMCs). Plumbagin also inhibited LPS-induced phosphorylation of p65, and the transcription of NF-κB target genes. Our results now show that plumbagin is a potent inhibitor of the NF-κB signaling pathway, and suppressor of T-ALL cell proliferation. - Highlights: • Plumbagin induces caspase-dependent apoptosis in T-ALL MOLT-4 cells. • Plumbagin activates phosphorylation of stress-activated protein kinase (SAPK) JNK and p38. • Plumbagin inhibits LPS-mediated NF-κB signaling cascade. • Plumbagin inhibits LPS-mediated transcriptional activity of pro-inflammatory cytokines.

  10. Deregulated WNT signaling in childhood T-cell acute lymphoblastic leukemia

    International Nuclear Information System (INIS)

    Ng, O H; Erbilgin, Y; Firtina, S; Celkan, T; Karakas, Z; Aydogan, G; Turkkan, E; Yildirmak, Y; Timur, C; Zengin, E; Dongen, J J M van; Staal, F J T; Ozbek, U; Sayitoglu, M

    2014-01-01

    WNT signaling has been implicated in the regulation of hematopoietic stem cells and plays an important role during T-cell development in thymus. Here we investigated WNT pathway activation in childhood T-cell acute lymphoblastic leukemia (T-ALL) patients. To evaluate the potential role of WNT signaling in T-cell leukomogenesis, we performed expression analysis of key components of WNT pathway. More than 85% of the childhood T-ALL patients showed upregulated β-catenin expression at the protein level compared with normal human thymocytes. The impact of this upregulation was reflected in high expression of known target genes (AXIN2, c-MYC, TCF1 and LEF). Especially AXIN2, the universal target gene of WNT pathway, was upregulated at both mRNA and protein levels in ∼40% of the patients. When β-CATENIN gene was silenced by small interfering RNA, the cancer cells showed higher rates of apoptosis. These results demonstrate that abnormal WNT signaling activation occurs in a significant fraction of human T-ALL cases independent of known T-ALL risk factors. We conclude that deregulated WNT signaling is a novel oncogenic event in childhood T-ALL

  11. How to train your T cell: genetically engineered chimeric antigen receptor T cells versus bispecific T-cell engagers to target CD19 in B acute lymphoblastic leukemia.

    Science.gov (United States)

    Ruella, Marco; Gill, Saar

    2015-06-01

    Antigen-specific T cell-based immunotherapy is getting its day in the sun. The contemporaneous development of two potent CD19-specific immunotherapeutic modalities for the treatment of B-cell malignancies provides exciting opportunities for patients, physicians and scientists alike. Patients with relapsed, refractory or poor-risk B-cell acute lymphoblastic leukemia (ALL) previously had few therapeutic options and now have two potential new lifelines. Physicians will have the choice between two powerful modalities and indeed could potentially enroll some patients on trials exploring both modalities if needed. For scientists interested in tumor immunology, the advent of chimeric antigen receptor T-cell therapy and of bispecific T-cell engagers (BiTEs) provides unprecedented opportunities to explore the promise and limitations of antigen-specific T-cell therapy in the context of human leukemia. In this article, we compare chimeric antigen receptor T cells and BiTEs targeting CD19 in B-cell ALL in the setting of the available clinical literature.

  12. Acute T- cell lymphoblastic lymphoma - A case report | Sumba | East ...

    African Journals Online (AJOL)

    We highlight the case of a two year old female who presented with a two month history of left posterior auricular swelling. The swelling developed following trauma, was painless and progressively enlarging. After extensive evaluation the mass was noted to be an extramedullary presentation of Acute T cell lymphoblastic ...

  13. Redirecting T cells to eradicate B-cell acute lymphoblastic leukemia: bispecific T-cell engagers and chimeric antigen receptors.

    Science.gov (United States)

    Aldoss, I; Bargou, R C; Nagorsen, D; Friberg, G R; Baeuerle, P A; Forman, S J

    2017-04-01

    Recent advances in antibody technology to harness T cells for cancer immunotherapy, particularly in the difficult-to-treat setting of relapsed/refractory acute lymphoblastic leukemia (r/r ALL), have led to innovative methods for directing cytotoxic T cells to specific surface antigens on cancer cells. One approach involves administration of soluble bispecific (or dual-affinity) antibody-based constructs that temporarily bridge T cells and cancer cells. Another approach infuses ex vivo-engineered T cells that express a surface plasma membrane-inserted antibody construct called a chimeric antigen receptor (CAR). Both bispecific antibodies and CARs circumvent natural target cell recognition by creating a physical connection between cytotoxic T cells and target cancer cells to activate a cytolysis signaling pathway; this connection allows essentially all cytotoxic T cells in a patient to be engaged because typical tumor cell resistance mechanisms (such as T-cell receptor specificity, antigen processing and presentation, and major histocompatibility complex context) are bypassed. Both the bispecific T-cell engager (BiTE) antibody construct blinatumomab and CD19-CARs are immunotherapies that have yielded encouraging remission rates in CD19-positive r/r ALL, suggesting that they might serve as definitive treatments or bridging therapies to allogeneic hematopoietic cell transplantation. With the introduction of these immunotherapies, new challenges arise related to unique toxicities and distinctive pathways of resistance. An increasing body of knowledge is being accumulated on how to predict, prevent, and manage such toxicities, which will help to better stratify patient risk and tailor treatments to minimize severe adverse events. A deeper understanding of the precise mechanisms of action and immune resistance, interaction with other novel agents in potential combinations, and optimization in the manufacturing process will help to advance immunotherapy outcomes in the r

  14. CAR-T cells and allogeneic hematopoietic stem cell transplantation for relapsed/refractory B-cell acute lymphoblastic leukemia.

    Science.gov (United States)

    Liu, Jun; Zhang, Xi; Zhong, Jiang F; Zhang, Cheng

    2017-10-01

    Relapsed/refractory acute lymphoblastic leukemia (ALL) has a low remission rate after chemotherapy, a high relapse rate and poor long-term survival even when allogeneic hematopoietic stem cell transplantation (allo-HSCT) is performed. Chimeric antigen receptors redirected T cells (CAR-T cells) can enhance disease remission with a favorable outcome for relapsed/refractory ALL, though some cases quickly relapsed after CAR-T cell treatment. Thus, treatment with CAR-T cells followed by allo-HSCT may be the best way to treat relapsed/refractory ALL. In this review, we first discuss the different types of CAR-T cells. We then discuss the treatment of relapsed/refractory ALL using only CAR-T cells. Finally, we discuss the use of CAR-T cells, followed by allo-HSCT, for the treatment of relapsed/refractory ALL.

  15. Immune Thrombocytopenia in a Child with T Cell Lymphoblastic Lymphoma

    Directory of Open Access Journals (Sweden)

    Kayo Tokeji

    2016-01-01

    Full Text Available We describe the case of a 13-year-old boy who presented with persistent thrombocytopenia during maintenance chemotherapy with mercaptopurine and methotrexate for T cell lymphoblastic lymphoma. He was diagnosed with immune thrombocytopenia (ITP after thorough investigations for the relapse of lymphoma and was successfully treated with immunoglobulin and steroids. ITP is known to be associated with chronic lymphocytic leukemia, Hodgkin lymphoma, and various types of non-Hodgkin lymphoma but rarely with T cell non-Hodgkin lymphoma or in children. Diagnosis of ITP with lymphoma is challenging due to the many factors affecting platelet counts, and ITP often complicates the diagnosis or treatment course of lymphoma. The underlying mechanism of ITP with NHL is still unclear. Drug-induced immunomodulation with a reduction of regulatory T cells might have contributed to the development of ITP in our case.

  16. Troglitazone inhibits cell growth and induces apoptosis of B-cell acute lymphoblastic leukemia cells with t(14;18).

    Science.gov (United States)

    Takenokuchi, M; Saigo, K; Nakamachi, Y; Kawano, S; Hashimoto, M; Fujioka, T; Koizumi, T; Tatsumi, E; Kumagai, S

    2006-01-01

    Peroxisome proliferator-activated receptor-gamma (PPARgamma), a member of the nuclear receptor superfamily, has been detected in several human leukemia cells. Recent studies reported that PPARgamma ligands inhibit cell proliferation and induce apoptosis in both normal and malignant B-lineage cells. We investigated the expression of PPARgamma and the effects of PPARgamma ligands on UTree-O2, Bay91 and 380, three B-cell acute lymphoblastic leukemia (B-ALL) cell lines with t(14;18), which show a poor prognosis, accompanying c-myc abnormality. Western blot analysis identified expression of PPARgamma protein and real-time PCR that of PPARgamma mRNA on the three cell lines. Troglitazone (TGZ), a synthetic PPARgamma ligand, inhibited cell growth in these cell lines in a dose-dependent manner, which was associated with G(1) cell cycle arrest and apoptosis. We also found this effect PPARgamma independent since PPARgamma antagonists failed to reverse this effect. We assessed the expression of c-myc, an apoptosis-regulatory gene, since c-myc abnormality was detected in most B-ALL cells with t(14;18). TGZ was found to dose-dependently downregulate the expression of c-myc mRNA and c-myc protein in the three cell lines. These results suggest that TGZ inhibits cell growth via induction of G(1) cell cycle arrest and apoptosis in these cell lines and that TGZ-induced apoptosis, at least in part, may be related to the downregulation of c-myc expression. Moreover, the downregulation of c-myc expression by TGZ may depend on a PPARgamma-independent mechanism. Further studies indicate that PPARgamma ligands may serve as a therapeutic agent in B-ALL with t(14;18).

  17. Human adenosine deaminase: properties and turnover in cultured T and B lymphoblasts

    International Nuclear Information System (INIS)

    Daddona, P.E.

    1981-01-01

    In this study, the properties and rate of turnover of adenosine deaminase are compared in cultured human T and B lymphoblast cell lines. 1) Relative to B lymphoblasts, the level of adenosine deaminase activity in extracts of T lymphoblast cell lines (MOLT-4, RPMI-8402, CCRF-CEM, and CCRF-HSB-2) is elevated 7-14-fold and differs by 2-fold between the C cell lines. 2) In both T and B lymphoblast extracts, the enzyme is apparently identical, based on K/sub m/ for adenosine and deoxyadenosine, K/sub i/ for inosine, V/sub max/ for adenosine, /sub S20,w/, isoelectric pH, and heat stability. Furthermore, by radioimmunoassay, the quantity of adenosine deaminase-immunocreative protein is proportional to the level of enzyme activity in all cell lines studies. 3) Using a purification and selective immunoprecipitation technique, the enzyme turnover could be assessed in cell lines labeled with [ 35 S]methionine. The apparent rate of adenosine deaminase synthesis, relative to total protein, is 2-fold faster in both T cell lines (RPMI-8402 and CCRF-CEM) than in the B cell lines (MGL-8 and GM-130). The apparent half-life (tsub1/2) for the enzyme degradation is 19 and 39 h, respectively, in CCFR-CEM and RPMI-8402, while the tsub1/2 in both B cell lines is 7-9 h. From the net rate of synthesis and degradation, the T cell lines, respectively, exhibit approximately a 6- and 12-fold difference in adenosine deaminase turnover relative to B cells, consistent with the observed differences in enzyme activity. This study suggests that while adenosine deaminase is apparently identical in both T and B lymphoblast cell lines, alterations in both the rate of enzyme synthesis and degradation contribute to its high steady state level in T cells

  18. The dual specificity PI3K/mTOR inhibitor PKI-587 displays efficacy against T-cell acute lymphoblastic leukemia (T-ALL).

    Science.gov (United States)

    Gazi, Mohiuddin; Moharram, Sausan A; Marhäll, Alissa; Kazi, Julhash U

    2017-04-28

    Although significant improvements have been made in the treatment of acute lymphoblastic leukemia (ALL), there is a substantial subset of high-risk T-cell ALL (T-ALL) patients with relatively poor prognosis. Like in other leukemia types, alterations of the PI3K/mTOR pathway are predominant in ALL which is also responsible for treatment failure and relapse. In this study, we show that relapsed T-ALL patients display an enrichment of the PI3K/mTOR pathway. Using a panel of inhibitors targeting multiple components of the PI3K/mTOR pathway, we observed that the dual-specific PI3K/mTOR inhibitor PKI-587 was the most selective inhibitor for T-ALL cells dependent on the PI3K/mTOR pathway. Furthermore, we observed that PKI-587 blocked proliferation and colony formation of T-ALL cell lines. Additionally, PKI-587 selectively abrogated PI3K/mTOR signaling without affecting MAPK signaling both in in vitro and in vivo. Inhibition of the PI3K/mTOR pathway using PKI-587 delayed tumor progression, reduced tumor load and enhanced the survival rate in immune-deficient mouse xenograft models without inducing weight loss in the inhibitor treated mice. This preclinical study shows beneficial effects of PKI-587 on T-ALL that warrants further investigation in the clinical setting. Copyright © 2017 Elsevier B.V. All rights reserved.

  19. Cholinergic Machinery as Relevant Target in Acute Lymphoblastic T Leukemia

    Directory of Open Access Journals (Sweden)

    Oxana Dobrovinskaya

    2016-08-01

    Full Text Available Various types of non-neuronal cells, including tumors, are able to produce acetylcholine (ACh, which acts as an autocrine/paracrine growth factor. T lymphocytes represent a key component of the non-neuronal cholinergic system. T cells-derived ACh is involved in a stimulation of their activation and proliferation, and acts as a regulator of immune response. The aim of the present work was to summarize the data about components of cholinergic machinery in T lymphocytes, with an emphasis on the comparison of healthy and leukemic T cells. Cell lines derived from acute lymphoblastic leukemias of T lineage (T-ALL were found to produce a considerably higher amount of ACh than healthy T lumphocytes. Additionally, ACh produced by T-ALL is not efficiently hydrolyzed, because acetylcholinesterase (AChE activity is drastically decreased in these cells. Up-regulation of muscarinic ACh receptors was also demonstrated at expression and functional level, whereas nicotinic ACh receptors seem to play a less important role and not form functional channels in cells derived from T-ALL. We hypothesized that ACh over-produced in T-ALL may act as an autocrine growth factor and play an important role in leukemic clonal expansion through shaping of intracellular Ca2+ signals. We suggest that cholinergic machinery may be attractive targets for new drugs against T-ALL. Specifically, testing of high affinity antagonists of muscarinic ACh receptors as well as antagomiRs, which interfere with miRNAs involved in the suppression of AChE expression, may be the first choice options.

  20. Effect of irradiation on human T-cell proliferation: low dose irradiation stimulates mitogen-induced proliferation and function of the suppressor/cytotoxic T-cell subset

    International Nuclear Information System (INIS)

    Gualde, N.; Goodwin, J.S.

    1984-01-01

    Unfractionated human T cells exposed to 10-50 rad of X irradiation incorporated less [ 3 H]thymidine than nonirradiated T cells when subsequently cultured with PHA or Con A. The cytotoxic/suppressor T-cell subset, isolated as either OKT8(+) or OKT4(-) cells, demonstrated significantly enhanced [ 3 H]thymidine incorporation in PHA- or Con A-stimulated cultures after exposure to 10-50 rad, compared to unirradiated cells, while the proliferation of the OKT4(+) helper/inducer subset was inhibited by low dose irradiation. It has been previously reported that approximately 30% of the cytotoxic/suppressor subset also stains with OKM1. When the cytotoxic/suppressor subset was further subdivided into OKT4(-), OKM1(+), and OKT4(-), OKM1(-) cells, proliferation of the OKT4(-), OKM1(+) population was inhibited by exposure to 25 rad while proliferation of the OKT4(-), OKM1(-) population was stimulated. The increase in proliferation of the cytotoxic/suppressor T-cell subset after low dose irradiation is paralleled by an increase in suppressor activity of these cells. T cells exposed to 25 rad and then cultured with Con A for 48 hr caused greater inhibition of IgG production when added to fresh autologous lymphocytes stimulated by pokeweed mitogen than did unirradiated cells. Thus, low dose irradiation enhances both the proliferation and function of the human suppressor T-cell subset

  1. Targeted sequencing identifies associations between IL7R-JAK mutations and epigenetic modulators in T-cell acute lymphoblastic leukemia

    Science.gov (United States)

    Vicente, Carmen; Schwab, Claire; Broux, Michaël; Geerdens, Ellen; Degryse, Sandrine; Demeyer, Sofie; Lahortiga, Idoya; Elliott, Alannah; Chilton, Lucy; La Starza, Roberta; Mecucci, Cristina; Vandenberghe, Peter; Goulden, Nicholas; Vora, Ajay; Moorman, Anthony V.; Soulier, Jean; Harrison, Christine J.; Clappier, Emmanuelle; Cools, Jan

    2015-01-01

    T-cell acute lymphoblastic leukemia is caused by the accumulation of multiple oncogenic lesions, including chromosomal rearrangements and mutations. To determine the frequency and co-occurrence of mutations in T-cell acute lymphoblastic leukemia, we performed targeted re-sequencing of 115 genes across 155 diagnostic samples (44 adult and 111 childhood cases). NOTCH1 and CDKN2A/B were mutated/deleted in more than half of the cases, while an additional 37 genes were mutated/deleted in 4% to 20% of cases. We found that IL7R-JAK pathway genes were mutated in 27.7% of cases, with JAK3 mutations being the most frequent event in this group. Copy number variations were also detected, including deletions of CREBBP or CTCF and duplication of MYB. FLT3 mutations were rare, but a novel extracellular mutation in FLT3 was detected and confirmed to be transforming. Furthermore, we identified complex patterns of pairwise associations, including a significant association between mutations in IL7R-JAK genes and epigenetic regulators (WT1, PRC2, PHF6). Our analyses showed that IL7R-JAK genetic lesions did not confer adverse prognosis in T-cell acute lymphoblastic leukemia cases enrolled in the UK ALL2003 trial. Overall, these results identify interconnections between the T-cell acute lymphoblastic leukemia genome and disease biology, and suggest a potential clinical application for JAK inhibitors in a significant proportion of patients with T-cell acute lymphoblastic leukemia. PMID:26206799

  2. Malignant T cells exhibit CD45 resistant Stat 3 activation and proliferation in cutaneous T cell lymphoma

    DEFF Research Database (Denmark)

    Krejsgaard, T; Helvad, Rikke; Ralfkiær, Elisabeth

    2010-01-01

    CD45 is a protein tyrosine phosphatase, which is well-known for regulating antigen receptor signalling in T and B cells via its effect on Src kinases. It has recently been shown that CD45 can also dephosphorylate Janus kinases (Jaks) and thereby regulate Signal transducer and activator of transcr......CD45 is a protein tyrosine phosphatase, which is well-known for regulating antigen receptor signalling in T and B cells via its effect on Src kinases. It has recently been shown that CD45 can also dephosphorylate Janus kinases (Jaks) and thereby regulate Signal transducer and activator...... of transcription (Stat) activation and cytokine-induced proliferation in lymphocytes. Consequently, CD45 dysregulation could be implicated in aberrant Jak/Stat activation and proliferation in lymphoproliferative diseases. Despite high expression of the CD45 ligand, Galectin-1, in skin lesions from cutaneous T......-cell lymphoma (CTCL), the malignant T cells exhibit constitutive activation of the Jak3/Stat3 signalling pathway and uncontrolled proliferation. We show that CD45 expression is down-regulated on malignant T cells when compared to non-malignant T cells established from CTCL skin lesions. Moreover, CD45 cross...

  3. tRNA modification profiles of the fast-proliferating cancer cells

    Energy Technology Data Exchange (ETDEWEB)

    Dong, Chao; Niu, Leilei; Song, Wei [State Key Laboratory of Natural and Biomimetic Drugs, School of Pharmaceutical Sciences, Department of Obstetrics and Gynecology, Peking University Third Hospital, Peking University, Beijing 100191 (China); Xiong, Xin; Zhang, Xianhua [Departmentof Pharmacy, Peking University Third Hospital, Peking University, Beijing 100191 (China); Zhang, Zhenxi; Yang, Yi; Yi, Fan [State Key Laboratory of Natural and Biomimetic Drugs, School of Pharmaceutical Sciences, Department of Obstetrics and Gynecology, Peking University Third Hospital, Peking University, Beijing 100191 (China); Zhan, Jun; Zhang, Hongquan [Department of Anatomy, Histology and Embryology, Laboratory of Molecular Cell Biology and Tumor Biology, Peking University, Beijing 100191 (China); Yang, Zhenjun; Zhang, Li-He [State Key Laboratory of Natural and Biomimetic Drugs, School of Pharmaceutical Sciences, Department of Obstetrics and Gynecology, Peking University Third Hospital, Peking University, Beijing 100191 (China); Zhai, Suodi [Departmentof Pharmacy, Peking University Third Hospital, Peking University, Beijing 100191 (China); Li, Hua, E-mail: huali88@sina.com [State Key Laboratory of Natural and Biomimetic Drugs, School of Pharmaceutical Sciences, Department of Obstetrics and Gynecology, Peking University Third Hospital, Peking University, Beijing 100191 (China); Ye, Min, E-mail: yemin@bjmu.edu.cn [State Key Laboratory of Natural and Biomimetic Drugs, School of Pharmaceutical Sciences, Department of Obstetrics and Gynecology, Peking University Third Hospital, Peking University, Beijing 100191 (China); Du, Quan, E-mail: quan.du@pku.edu.cn [State Key Laboratory of Natural and Biomimetic Drugs, School of Pharmaceutical Sciences, Department of Obstetrics and Gynecology, Peking University Third Hospital, Peking University, Beijing 100191 (China)

    2016-08-05

    Despite the recent progress in RNA modification study, a comprehensive modification profile is still lacking for mammalian cells. Using a quantitative HPLC/MS/MS assay, we present here a study where RNA modifications are examined in term of the major RNA species. With paired slow- and fast-proliferating cell lines, distinct RNA modification profiles are first revealed for diverse RNA species. Compared to mRNAs, increased ribose and nucleobase modifications are shown for the highly-structured tRNAs and rRNAs, lending support to their contribution to the formation of high-order structures. This study also reveals a dynamic tRNA modification profile in the fast-proliferating cells. In addition to cultured cells, this unique tRNA profile has been further confirmed with endometrial cancers and their adjacent normal tissues. Taken together, the results indicate that tRNA is a actively regulated RNA species in the fast-proliferating cancer cells, and suggest that they may play a more active role in biological process than expected. -- Highlights: •RNA modifications were first examined in term of the major RNA species. •A dynamic tRNA modifications was characterized for the fast-proliferating cells. •The unique tRNA profile was confirmed with endometrial cancers and their adjacent normal tissues. •tRNA was predicted as an actively regulated RNA species in the fast-proliferating cancer cells.

  4. tRNA modification profiles of the fast-proliferating cancer cells

    International Nuclear Information System (INIS)

    Dong, Chao; Niu, Leilei; Song, Wei; Xiong, Xin; Zhang, Xianhua; Zhang, Zhenxi; Yang, Yi; Yi, Fan; Zhan, Jun; Zhang, Hongquan; Yang, Zhenjun; Zhang, Li-He; Zhai, Suodi; Li, Hua; Ye, Min; Du, Quan

    2016-01-01

    Despite the recent progress in RNA modification study, a comprehensive modification profile is still lacking for mammalian cells. Using a quantitative HPLC/MS/MS assay, we present here a study where RNA modifications are examined in term of the major RNA species. With paired slow- and fast-proliferating cell lines, distinct RNA modification profiles are first revealed for diverse RNA species. Compared to mRNAs, increased ribose and nucleobase modifications are shown for the highly-structured tRNAs and rRNAs, lending support to their contribution to the formation of high-order structures. This study also reveals a dynamic tRNA modification profile in the fast-proliferating cells. In addition to cultured cells, this unique tRNA profile has been further confirmed with endometrial cancers and their adjacent normal tissues. Taken together, the results indicate that tRNA is a actively regulated RNA species in the fast-proliferating cancer cells, and suggest that they may play a more active role in biological process than expected. -- Highlights: •RNA modifications were first examined in term of the major RNA species. •A dynamic tRNA modifications was characterized for the fast-proliferating cells. •The unique tRNA profile was confirmed with endometrial cancers and their adjacent normal tissues. •tRNA was predicted as an actively regulated RNA species in the fast-proliferating cancer cells.

  5. Transcriptional regulatory networks downstream of TAL1/SCL in T-cell acute lymphoblastic leukemia

    OpenAIRE

    Palomero, Teresa; Odom, Duncan T.; O'Neil, Jennifer; Ferrando, Adolfo A.; Margolin, Adam; Neuberg, Donna S.; Winter, Stuart S.; Larson, Richard S.; Li, Wei; Liu, X. Shirley; Young, Richard A.; Look, A. Thomas

    2006-01-01

    Aberrant expression of 1 or more transcription factor oncogenes is a critical component of the molecular pathogenesis of human T-cell acute lymphoblastic leukemia (T-ALL); however, oncogenic transcriptional programs downstream of T-ALL oncogenes are mostly unknown. TAL1/SCL is a basic helix-loop-helix (bHLH) transcription factor oncogene aberrantly expressed in 60% of human T-ALLs. We used chromatin immunoprecipitation (ChIP) on chip to identify 71 direct transcriptional targets of TAL1/SCL. ...

  6. Transcriptional activation of prostate specific homeobox gene NKX3-1 in subsets of T-cell lymphoblastic leukemia (T-ALL.

    Directory of Open Access Journals (Sweden)

    Stefan Nagel

    Full Text Available Homeobox genes encode transcription factors impacting key developmental processes including embryogenesis, organogenesis, and cell differentiation. Reflecting their tight transcriptional control, homeobox genes are often embedded in large non-coding, cis-regulatory regions, containing tissue specific elements. In T-cell acute lymphoblastic leukemia (T-ALL homeobox genes are frequently deregulated by chromosomal aberrations, notably translocations adding T-cell specific activatory elements. NKX3-1 is a prostate specific homeobox gene activated in T-ALL patients expressing oncogenic TAL1 or displaying immature T-cell characteristics. After investigating regulation of NKX3-1 in primary cells and cell lines, we report its ectopic expression in T-ALL cells independent of chromosomal rearrangements. Using siRNAs and expression profiling, we exploited NKX3-1 positive T-ALL cell lines as tools to investigate aberrant activatory mechanisms. Our data confirmed NKX3-1 activation by TAL1/GATA3/LMO and identified LYL1 as an alternative activator in immature T-ALL cells devoid of GATA3. Moreover, we showed that NKX3-1 is directly activated by early T-cell homeodomain factor MSX2. These activators were regulated by MLL and/or by IL7-, BMP4- and IGF2-signalling. Finally, we demonstrated homeobox gene SIX6 as a direct leukemic target of NKX3-1 in T-ALL. In conclusion, we identified three major mechanisms of NKX3-1 regulation in T-ALL cell lines which are represented by activators TAL1, LYL1 and MSX2, corresponding to particular T-ALL subtypes described in patients. These results may contribute to the understanding of leukemic transcriptional networks underlying disturbed T-cell differentiation in T-ALL.

  7. Suboptimal T-cell receptor signaling compromises protein translation, ribosome biogenesis, and proliferation of mouse CD8 T cells.

    Science.gov (United States)

    Tan, Thomas C J; Knight, John; Sbarrato, Thomas; Dudek, Kate; Willis, Anne E; Zamoyska, Rose

    2017-07-25

    Global transcriptomic and proteomic analyses of T cells have been rich sources of unbiased data for understanding T-cell activation. Lack of full concordance of these datasets has illustrated that important facets of T-cell activation are controlled at the level of translation. We undertook translatome analysis of CD8 T-cell activation, combining polysome profiling and microarray analysis. We revealed that altering T-cell receptor stimulation influenced recruitment of mRNAs to heavy polysomes and translation of subsets of genes. A major pathway that was compromised, when TCR signaling was suboptimal, was linked to ribosome biogenesis, a rate-limiting factor in both cell growth and proliferation. Defective TCR signaling affected transcription and processing of ribosomal RNA precursors, as well as the translation of specific ribosomal proteins and translation factors. Mechanistically, IL-2 production was compromised in weakly stimulated T cells, affecting the abundance of Myc protein, a known regulator of ribosome biogenesis. Consequently, weakly activated T cells showed impaired production of ribosomes and a failure to maintain proliferative capacity after stimulation. We demonstrate that primary T cells respond to various environmental cues by regulating ribosome biogenesis and mRNA translation at multiple levels to sustain proliferation and differentiation.

  8. Antigen-specific cytotoxic T cell and antigen-specific proliferating T cell clones can be induced to cytolytic activity by monoclonal antibodies against T3

    NARCIS (Netherlands)

    Spits, H.; Yssel, H.; Leeuwenberg, J.; de Vries, J. E.

    1985-01-01

    T3 is a human differentiation antigen expressed exclusively on mature T cells. In this study it is shown that anti-T3 monoclonal antibodies, in addition to their capacity to induce T cells to proliferate, are able to induce antigen-specific cytotoxic T lymphocyte clones to mediate antigen

  9. FBXW7 and NOTCH1 mutations in childhood T cell acute lymphoblastic leukaemia and T cell non-Hodgkin lymphoma.

    Science.gov (United States)

    Park, Myoung-Ja; Taki, Tomohiko; Oda, Megumi; Watanabe, Tomoyuki; Yumura-Yagi, Keiko; Kobayashi, Ryoji; Suzuki, Nobuhiro; Hara, Junichi; Horibe, Keizo; Hayashi, Yasuhide

    2009-04-01

    Mutation analysis of FBXW7 and NOTCH1 genes was performed in 55 T cell acute lymphoblastic leukaemia (T-ALL) and 14 T cell non-Hodgkin lymphoma (T-NHL) patients who were treated on the Japan Association of Childhood Leukaemia Study (JACLS) protocols ALL-97 and NHL-98. FBXW7 and/or NOTCH1 mutations were found in 22 (40.0%) of 55 T-ALL and 7 (50.0%) of 14 T-NHL patients. FBXW7 mutations were found in 8 (14.6%) of 55 T-ALL and 3 (21.4%) of 14 T-NHL patients, and NOTCH1 mutations in 17 (30.9%) of 55 T-ALL and 6 (42.9%) of 14 T-NHL patients. Three (5.4%) T-ALL and two (1.4%) T-NHL patients had mutations in both FBXW7 and NOTCH1. FBXW7 mutations included one insertion, one deletion, one deletion/insertion and nine missense mutations. NOTCH1 mutations were detected in the heterodimerization domain (HD) in 15 cases, in the PEST domain in seven cases, and in both the HD and PEST domains in one case. Five-year event-free survival and overall survival for patients with FBXW7 and/or NOTCH1 mutations were 95.5% (95% CI, 71.9-99.4%) and 100% respectively, suggesting that T-ALL patients with FBXW7 and/or NOTCH1 mutation represent a good prognosis compared to those without FBXW7 and/or NOTCH1 mutations (63.6%, P = 0.007 and 78.8%, P = 0.023, respectively).

  10. NF-κB in T-cell Acute Lymphoblastic Leukemia: Oncogenic Functions in Leukemic and in Microenvironmental Cells

    International Nuclear Information System (INIS)

    Santos, Nuno R. dos; Ghezzo, Marinella N.; Silva, Ricardo C. da; Fernandes, Mónica T.

    2010-01-01

    Two main NF-κB signaling pathways, canonical and noncanonical, performing distinct functions in organisms have been characterized. Identification of mutations in genes encoding components of these NF-κB signaling pathways in lymphoid malignancies confirmed their key role in leukemogenesis. T-cell acute lymphoblastic leukemia (T-ALL) is an aggressive malignancy of thymocytes that despite significant therapeutic advances can still be fatal. Although mutations in NF-κB genes have not been reported in T-ALL, NF-κB constitutive activation in human T-ALL and in acute T-cell leukemia mouse models has been observed. Although these studies revealed activation of members of both canonical and noncanonical NF-κB pathways in acute T-cell leukemia, only inhibition of canonical NF-κB signaling was shown to impair leukemic T cell growth. Besides playing an important pro-oncogenic role in leukemic T cells, NF-κB signaling also appears to modulate T-cell leukemogenesis through its action in microenvironmental stromal cells. This article reviews recent data on the role of these transcription factors in T-ALL and pinpoints further research crucial to determine the value of NF-κB inhibition as a means to treat T-ALL

  11. NF-κB in T-cell Acute Lymphoblastic Leukemia: Oncogenic Functions in Leukemic and in Microenvironmental Cells

    Energy Technology Data Exchange (ETDEWEB)

    Santos, Nuno R. dos, E-mail: nrsantos@ualg.pt; Ghezzo, Marinella N.; Silva, Ricardo C. da; Fernandes, Mónica T. [IBB-Institute for Biotechnology and Bioengineering, Centre for Molecular and Structural Biomedicine (CBME), University of Algarve, Campus de Gambelas, 8005-139 Faro (Portugal)

    2010-11-05

    Two main NF-κB signaling pathways, canonical and noncanonical, performing distinct functions in organisms have been characterized. Identification of mutations in genes encoding components of these NF-κB signaling pathways in lymphoid malignancies confirmed their key role in leukemogenesis. T-cell acute lymphoblastic leukemia (T-ALL) is an aggressive malignancy of thymocytes that despite significant therapeutic advances can still be fatal. Although mutations in NF-κB genes have not been reported in T-ALL, NF-κB constitutive activation in human T-ALL and in acute T-cell leukemia mouse models has been observed. Although these studies revealed activation of members of both canonical and noncanonical NF-κB pathways in acute T-cell leukemia, only inhibition of canonical NF-κB signaling was shown to impair leukemic T cell growth. Besides playing an important pro-oncogenic role in leukemic T cells, NF-κB signaling also appears to modulate T-cell leukemogenesis through its action in microenvironmental stromal cells. This article reviews recent data on the role of these transcription factors in T-ALL and pinpoints further research crucial to determine the value of NF-κB inhibition as a means to treat T-ALL.

  12. Rearrangements and amplification of the ABL1 gene as an example of kinase activation in T-cell acute lymphoblastic

    OpenAIRE

    Graux, Carlos

    2008-01-01

    T-cell acute lymphoblastic leukemia (T-ALL) is a neoplastic disorder that develops from a single hematopoietic T-cell precursor that acquired oncogenic anomalies. T-ALL is a heterogeneous disease comprising several clinico-biological entities characterized by distinct underlying genetic defects. In the first part of this work, we attempted to correlate those numerous anomalies with the role of the corresponding non mutated genes or pathways in normal T-cell development. Mutations targeting se...

  13. Accumulation of cytolytic CD8{sup +} T cells in B16-melanoma and proliferation of mature T cells in TIS21-knockout mice after T cell receptor stimulation

    Energy Technology Data Exchange (ETDEWEB)

    Ryu, Min Sook [Department of Biochemistry and Molecular Biology, Ajou University School of Medicine, 164, World cul-ro, Yeongtong-gu, Suwon, Gyeonggi-do 443-380 (Korea, Republic of); Woo, Min-Yeong [Department of Microbiology, Ajou University School of Medicine, 164, World cul-ro, Yeongtong-gu, Suwon, Gyeonggi-do 443-380 (Korea, Republic of); Department of Biomedical Sciences, The Graduate School, Ajou University (Korea, Republic of); Kwon, Daeho [Department of Microbiology, Kwandong University College of Medicine, Gangneung, Gangwon-do 210-701 (Korea, Republic of); Hong, Allen E. [Department of Biochemistry and Molecular Biology, Ajou University School of Medicine, 164, World cul-ro, Yeongtong-gu, Suwon, Gyeonggi-do 443-380 (Korea, Republic of); Song, Kye Yong [Department of Pathology, Chung-Ang University College of Medicine, Dongjak-gu, Seoul 156-756 (Korea, Republic of); Park, Sun [Department of Microbiology, Ajou University School of Medicine, 164, World cul-ro, Yeongtong-gu, Suwon, Gyeonggi-do 443-380 (Korea, Republic of); Lim, In Kyoung [Department of Biochemistry and Molecular Biology, Ajou University School of Medicine, 164, World cul-ro, Yeongtong-gu, Suwon, Gyeonggi-do 443-380 (Korea, Republic of)

    2014-10-01

    In vivo and in vitro effects of TIS21 gene on the mature T cell activation and antitumor activities were explored by employing MO5 melanoma orthograft and splenocytes isolated from the TIS21-knockout (KO) mice. Proliferation and survival of mature T cells were significantly increased in the KO than the wild type (WT) cells, indicating that TIS21 inhibits the rate of mature T cell proliferation and its survival. In MO5 melanoma orthograft model, the KO mice recruited much more CD8{sup +} T cells into the tumors at around day 14 after tumor cell injection along with reduced tumor volumes compared with the WT. The increased frequency of granzyme B{sup +} CD8{sup +} T cells in splenocytes of the KO mice compared with the WT may account for antitumor-immunity of TIS21 gene in the melanoma orthograft. In contrast, reduced frequencies of CD107a{sup +} CD8{sup +} T cells in the splenocytes of KO mice may affect the loss of CD8{sup +} T cell infiltration in the orthograft at around day 19. These results indicate that TIS21 exhibits antiproliferative and proapoptotic effects in mature T cells, and differentially affects the frequencies of granzyme B{sup +} CD8{sup +} T-cells and CD107a{sup +} CD8{sup +} T-cells, thus transiently regulating in vivo anti-tumor immunity. - Highlights: • Constitutive expression of TIS21 in splenocytes and upregulation by TCR stimulation. • Proliferation of mature T-cells in spleen of TIS21KO mice after TCR stimulation. • Inhibition of cell death in mature T-cells of TIS21KO mice compared with the wild type. • Inhibition of melanoma growth in TIS21KO mice and CD8{sup +} T cell infiltration in tumor. • Reduction of CD 107{sup +}CD8{sup +} T cells, but increased granzyme B{sup +} CD8{sup +} T cells in TIS21KO mice.

  14. IL-7 Receptor Mutations and Steroid Resistance in Pediatric T cell Acute Lymphoblastic Leukemia: A Genome Sequencing Study

    NARCIS (Netherlands)

    Y. Li (Yan); J.G.C.A.M. Buijs-Gladdines (Jessica); K. Canté-Barrett (Kirsten); A. Stubbs (Andrew); E.M. Vroegindeweij (Eric); W.K. Smits; R. van Marion (Ronald); W.N.M. Dinjens (Winand); M.A. Horstmann (Martin); R. Kuiper (Ruud); R.C. Buijsman; G.J.R. Zaman; P.J. van der Spek (Peter); R. Pieters (Rob); J.P.P. Meijerink (Jules)

    2016-01-01

    textabstractBackground: Pediatric acute lymphoblastic leukemia (ALL) is the most common childhood cancer and the leading cause of cancer-related mortality in children. T cell ALL (T-ALL) represents about 15% of pediatric ALL cases and is considered a high-risk disease. T-ALL is often associated with

  15. Fusion of NUP98 and the SET binding protein 1 (SETBP1) gene in a paediatric acute T cell lymphoblastic leukaemia with t(11;18)(p15;q12)

    DEFF Research Database (Denmark)

    Panagopoulos, Ioannis; Kerndrup, Gitte; Carlsen, Niels

    2007-01-01

    Three NUP98 chimaeras have previously been reported in T cell acute lymphoblastic leukaemia (T-ALL): NUP98/ADD3, NUP98/CCDC28A, and NUP98/RAP1GDS1. We report a T-ALL with t(11;18)(p15;q12) resulting in a novel NUP98 fusion. Fluorescent in situ hybridisation showed NUP98 and SET binding protein 1(...... in leukaemias; however, it encodes a protein that specifically interacts with SET, fused to NUP214 in a case of acute undifferentiated leukaemia.......Three NUP98 chimaeras have previously been reported in T cell acute lymphoblastic leukaemia (T-ALL): NUP98/ADD3, NUP98/CCDC28A, and NUP98/RAP1GDS1. We report a T-ALL with t(11;18)(p15;q12) resulting in a novel NUP98 fusion. Fluorescent in situ hybridisation showed NUP98 and SET binding protein 1...

  16. The t(10;14)(q24;q11) of T-cell acute lymphoblastic leukemia juxtaposes the δT-cell receptor with TCL3, a conserved and activated locus at 10q24

    International Nuclear Information System (INIS)

    Zutter, M.; Hockett, R.D.; Roberts, C.W.M.; McGuire, E.A.; Bloomstone, J.; Korsmeyer, S.J.; Morton, C.C.; Deaven, L.L.; Crist, W.M.; Carroll, A.J.

    1990-01-01

    The authors cloned the t(10;14) recurrent translocation from CD3-negative T-cell acute lymphoblastic leukemia cells. The breakpoint at 14q11 involved an intermediate rearrangement of the δ T-cell receptor locus, suggesting that the translocation arose at the time of antigen receptor assemblage. Translocation introduced chromosome segment 10q24 as proven by hybridization of a breakpoint-derived probe to flow-sorted chromosomes and metaphase chromosomes. Two t(10;14) breakpoints were clustered within a 600-base-pair region of 10q24 but no heptamer-spacer-nonamer motifs resembling T-cell receptor/immunoglobulin rearrangement signals were noted at the breakpoint. A locus distinct from terminal deoxynucleotidyltransferase was found at 10q24. Evolutionarily conserved regions surrounding the 10q24 breakpoint were examined for transcriptional activity. A region telomeric to the 10q24 breakpoint, expected to translocate to the der(14) chromosome, recognized an abundant 2.9-kilobase RNA in a t(10;14) T-cell leukemia. This locus was not active in a variety of other normal and neoplastic T cells, arguing that it was deregulated by he introduction of the T-cell receptor. This locus is a candidate for a putative protooncogene, TCL3, involved in T-cell neoplasia

  17. Trehalose improves cell proliferation and dehydration tolerance of human HaCaT cells

    Directory of Open Access Journals (Sweden)

    Lee Kyung Eun

    2015-01-01

    Full Text Available Trehalose is a disaccharide molecule that serves as a natural osmotic regulator in halophilic microorganisms and plants but not in mammals. We observed that human HaCaT cells supplied with trehalose improved cell proliferation and extended viability under dehydration. In HaCaT cells, in response to increasing concentrations of exogenous trehalose, the levels of heat shock protein (HSP 70 increased and matrix metalloproteinase (MMP 1 decreased. Proteome analysis of trehalose-treated HaCaT cells revealed remarkable increases in the levels of proteins involved in cell signaling and the cell cycle, including p21 activated kinase I, Sec I family domain protein and elongation factor G. Moreover, the proteins for cell stress resistance, tryptophan hydroxylase, serine/cysteine proteinase inhibitors and vitamin D receptors were also increased. In addition, the proteins responsible for the maintenance of the cytoskeleton and cellular structures including procollagen-lysine dioxygenase, vinculin and ezrin were increased. Proteomic data revealed that trehalose affected HaCaT cells by inducing the proteins involved in cell proliferation. These results suggest that trehalose improves the proliferation and dehydration tolerance of HaCaT cells by inducing proteins involved in cell growth and dehydration protection.

  18. Human mesenchymal stromal cells transiently increase cytokine production by activated T cells before suppressing T-cell proliferation: effect of interferon-γ and tumor necrosis factor-α stimulation.

    Science.gov (United States)

    Cuerquis, Jessica; Romieu-Mourez, Raphaëlle; François, Moïra; Routy, Jean-Pierre; Young, Yoon Kow; Zhao, Jing; Eliopoulos, Nicoletta

    2014-02-01

    Mesenchymal stromal cells (MSCs) suppress T-cell proliferation, especially after activation with inflammatory cytokines. We compared the dynamic action of unprimed and interferon (IFN)-γ plus tumor necrosis factor (TNF)-α-pretreated human bone marrow-derived MSCs on resting or activated T cells. MSCs were co-cultured with allogeneic peripheral blood mononuclear cells (PBMCs) at high MSC-to-PBMC ratios in the absence or presence of concomitant CD3/CD28-induced T-cell activation. The kinetic effects of MSCs on cytokine production and T-cell proliferation, cell cycle and apoptosis were assessed. Unprimed MSCs increased the early production of IFN-γ and interleukin (IL)-2 by CD3/CD28-activated PBMCs before suppressing T-cell proliferation. In non-activated PBMC co-cultures, low levels of IL-2 and IL-10 synthesis were observed with MSCs in addition to low levels of CD69 expression by T cells and no T-cell proliferation. MSCs also decreased apoptosis in resting and activated T cells and inhibited the transition of these cells into the sub-G0/G1 and the S phases. With inhibition of indoleamine 2,3 dioxygenase, MSCs increased CD3/CD28-induced T-cell proliferation. After priming with IFN-γ plus TNF-α, MSCs were less potent at increasing cytokine production by CD3/CD28-activated PBMCs and more effective at inhibiting T-cell proliferation but had preserved anti-apoptotic functions. Unprimed MSCs induce a transient increase in IFN-γ and IL-2 synthesis by activated T cells. Pre-treatment of MSCs with IFN-γ plus TNF-α may increase their effectiveness and safety in vivo. Copyright © 2014 International Society for Cellular Therapy. Published by Elsevier Inc. All rights reserved.

  19. Eosinophils from hematopoietic stem cell recipients suppress allogeneic T cell proliferation.

    Science.gov (United States)

    Andersson, Jennie; Cromvik, Julia; Ingelsten, Madeleine; Lingblom, Christine; Andersson, Kerstin; Johansson, Jan-Erik; Wennerås, Christine

    2014-12-01

    Eosinophilia has been associated with less severe graft-versus-host disease (GVHD), but the underlying mechanism is unknown. We hypothesized that eosinophils diminish allogeneic T cell activation in patients with chronic GVHD. The capacity of eosinophils derived from healthy subjects and hematopoietic stem cell (HSC) transplant recipients, with or without chronic GVHD, to reduce allogeneic T cell proliferation was evaluated using a mixed leukocyte reaction. Eosinophil-mediated inhibition of proliferation was observed for the eosinophils of both healthy subjects and patients who underwent HSC transplantation. Eosinophils from patients with and without chronic GVHD were equally suppressive. Healthy eosinophils required cell-to-cell contact for their suppressive capacity, which was directed against CD4(+) T cells and CD8(+) T cells. Neither eosinophilic cationic protein, eosinophil-derived neurotoxin, indoleamine 2,3-dioxygenase, or increased numbers of regulatory T cells could account for the suppressive effect of healthy eosinophils. Real-time quantitative PCR analysis revealed significantly increased mRNA levels of the immunoregulatory protein galectin-10 in the eosinophils of both chronic GVHD patients and patients without GVHD, as compared with those from healthy subjects. The upregulation of galectin-10 expression in eosinophils from patients suggests a stimulatory effect of HSC transplantation in itself on eosinophilic galectin-10 expression, regardless of chronic GVHD status. To conclude, eosinophils from HSC transplant recipients and healthy subjects have a T cell suppressive capacity. Copyright © 2014 American Society for Blood and Marrow Transplantation. Published by Elsevier Inc. All rights reserved.

  20. Age-related clinical and biological features of PTEN abnormalities in T-cell acute lymphoblastic leukaemia.

    Science.gov (United States)

    Tesio, M; Trinquand, A; Ballerini, P; Hypolite, G; Lhermitte, L; Petit, A; Ifrah, N; Baruchel, A; Dombret, H; Macintyre, E; Asnafi, V

    2017-12-01

    The tumour suppressor gene PTEN is commonly altered in T-cell acute lymphoblastic leukaemia but its prognostic impact is still debated. We screened a cohort of 573 fully characterised adult and paediatric T-cell acute lymphoblastic leukaemia (T-ALL) patients for genomic PTEN abnormalities. PTEN-inactivating mutations and/or deletions were identified in 91 cases (16%), including 18% of paediatric (49/277) and 14% of adult cases (42/296). Thirty-four patients harboured only mutations, 12 cases demonstrated only large deletions and 9 only microdeletions. About 36 patients had combined alterations. Different mechanisms of PTEN inactivation predicted differences in the clinical outcome for both adult and paediatric patients treated according to the GRAALL03/05 and FRALLE2000 protocols. Whereas large deletions predicted lower 5-year overall survival (P=0.0053 in adults, P=0.001 in children) and disease-free survival (P=0.0009 in adults, P=0.0002 in children), mutations were not associated with a worse prognosis. The prognostic impact of PTEN loss is therefore linked to the underlying type of genomic abnormality, both in adult and paediatric T-ALLs, demonstrating that detailed analysis of the type of abnormality type would be useful to refine risk stratification.

  1. Dissecting the T Cell Response: Proliferation Assays vs. Cytokine Signatures by ELISPOT

    Directory of Open Access Journals (Sweden)

    Magdalena Tary-Lehmann

    2012-05-01

    Full Text Available Chronic allograft rejection is in part mediated by host T cells that recognize allogeneic antigens on transplanted tissue. One factor that determines the outcome of a T cell response is clonal size, while another is the effector quality. Studies of alloimmune predictors of transplant graft survival have most commonly focused on only one measure of the alloimmune response. Because differing qualities and frequencies of the allospecific T cell response may provide distinctly different information we analyzed the relationship between frequency of soluble antigen and allo-antigen specific memory IFN-g secreting CD4 and CD8 T cells, their ability to secrete IL-2, and their proliferative capacity, while accounting for cognate and bystander proliferation. The results show proliferative responses primarily reflect on IL-2 production by antigen-specific T cells, and that proliferating cells in such assays entail a considerable fraction of bystander cells. On the other hand, proliferation (and IL-2 production did not reflect on the frequency of IFN-γ producing memory cells, a finding particularly accentuated in the CD8 T cell compartment. These data provide rationale for considering both frequency and effector function of pre-transplant T cell reactivity when analyzing immune predictors of graft rejection.

  2. Dissecting the T Cell Response: Proliferation Assays vs. Cytokine Signatures by ELISPOT

    Science.gov (United States)

    Anthony, Donald D.; Milkovich, Kimberly A.; Zhang, Wenji; Rodriguez, Benigno; Yonkers, Nicole L.; Tary-Lehmann, Magdalena; Lehmann, Paul V.

    2012-01-01

    Chronic allograft rejection is in part mediated by host T cells that recognize allogeneic antigens on transplanted tissue. One factor that determines the outcome of a T cell response is clonal size, while another is the effector quality. Studies of alloimmune predictors of transplant graft survival have most commonly focused on only one measure of the alloimmune response. Because differing qualities and frequencies of the allospecific T cell response may provide distinctly different information we analyzed the relationship between frequency of soluble antigen and allo-antigen specific memory IFN-γ secreting CD4 and CD8 T cells, their ability to secrete IL-2, and their proliferative capacity, while accounting for cognate and bystander proliferation. The results show proliferative responses primarily reflect on IL-2 production by antigen-specific T cells, and that proliferating cells in such assays entail a considerable fraction of bystander cells. On the other hand, proliferation (and IL-2 production) did not reflect on the frequency of IFN-γ producing memory cells, a finding particularly accentuated in the CD8 T cell compartment. These data provide rationale for considering both frequency and effector function of pre-transplant T cell reactivity when analyzing immune predictors of graft rejection. PMID:24710419

  3. The oncogenic fusion protein RUNX1-CBFA2T1 supports proliferation and inhibits senescence in t(8;21)-positive leukaemic cells

    International Nuclear Information System (INIS)

    Martinez, Natalia; Heidenreich, Olaf; Drescher, Bettina; Riehle, Heidemarie; Cullmann, Claire; Vornlocher, Hans-Peter; Ganser, Arnold; Heil, Gerhard; Nordheim, Alfred; Krauter, Jürgen

    2004-01-01

    The fusion protein RUNX1-CBFA2T1 associated with t(8;21)-positive acute myeloid leukaemia is a potent inhibitor of haematopoetic differentiation. The role of RUNX1-CBFA2T1 in leukaemic cell proliferation is less clear. We examined the consequences of siRNA-mediated RUNX1-CBFA2T1 depletion regarding proliferation and clonogenicity of t(8;21)-positive cell lines. The t(8;21)-positive cell line Kasumi-1 was electroporated with RUNX1-CBFA2T1 or control siRNAs followed by analysis of proliferation, colony formation, cell cycle distribution, apoptosis and senescence. Electroporation of Kasumi-1 cells with RUNX1-CBFA2T1 siRNAs, but not with control siRNAs, resulted in RUNX1-CBFA2T1 suppression which lasted for at least 5 days. A single electroporation with RUNX1-CBFA2T1 siRNA severely diminished the clonogenicity of Kasumi-1 cells. Prolonged RUNX1-CBFA2T1 depletion inhibited proliferation in suspension culture and G1-S transition during the cell cycle, diminished the number of apoptotic cells, but induced cellular senescence. The addition of haematopoetic growth factors could not rescue RUNX1-CBFA2T1-depleted cells from senescence, and could only partially restore their clonogenicity. RUNX1-CBFA2T1 supports the proliferation and expansion of t(8;21)-positive leukaemic cells by preventing cellular senescence. These findings suggest a central role of RUNX1-CBFA2T1 in the maintenance of the leukaemia. Therefore, RUNX1-CBFA2T1 is a promising and leukaemia-specific target for molecularly defined therapeutic approaches

  4. The significance of PTEN and AKT aberrations in pediatric T-cell acute lymphoblastic leukemia

    Science.gov (United States)

    Zuurbier, Linda; Petricoin, Emanuel F.; Vuerhard, Maartje J.; Calvert, Valerie; Kooi, Clarissa; Buijs-Gladdines, Jessica G.C.A.M.; Smits, Willem K.; Sonneveld, Edwin; Veerman, Anjo J.P.; Kamps, Willem A.; Horstmann, Martin; Pieters, Rob; Meijerink, Jules P.P.

    2012-01-01

    Background PI3K/AKT pathway mutations are found in T-cell acute lymphoblastic leukemia, but their overall impact and associations with other genetic aberrations is unknown. PTEN mutations have been proposed as secondary mutations that follow NOTCH1-activating mutations and cause cellular resistance to γ-secretase inhibitors. Design and Methods The impact of PTEN, PI3K and AKT aberrations was studied in a genetically well-characterized pediatric T-cell leukemia patient cohort (n=146) treated on DCOG or COALL protocols. Results PTEN and AKT E17K aberrations were detected in 13% and 2% of patients, respectively. Defective PTEN-splicing was identified in incidental cases. Patients without PTEN protein but lacking exon-, splice-, promoter mutations or promoter hypermethylation were present. PTEN/AKT mutations were especially abundant in TAL- or LMO-rearranged leukemia but nearly absent in TLX3-rearranged patients (P=0.03), the opposite to that observed for NOTCH1-activating mutations. Most PTEN/AKT mutant patients either lacked NOTCH1-activating mutations (P=0.006) or had weak NOTCH1-activating mutations (P=0.011), and consequently expressed low intracellular NOTCH1, cMYC and MUSASHI levels. T-cell leukemia patients without PTEN/AKT and NOTCH1-activating mutations fared well, with a cumulative incidence of relapse of only 8% versus 35% for PTEN/AKT and/or NOTCH1-activated patients (P=0.005). Conclusions PI3K/AKT pathway aberrations are present in 18% of pediatric T-cell acute lymphoblastic leukemia patients. Absence of strong NOTCH1-activating mutations in these cases may explain cellular insensitivity to γ-secretase inhibitors. PMID:22491738

  5. Identification and cloning of a prethymic precursor T lymphocyte from a population of common acute lymphoblastic leukemia antigen (CALLA)-positive fetal bone marrow cells

    DEFF Research Database (Denmark)

    Hokland, P; Hokland, M; Daley, J

    1987-01-01

    We have cloned common acute lymphoblastic leukemia (CALLA)-positive cells from human fetal bone marrow containing less than 1 in 10,000 E-RFC in round-bottomed microtiter wells (one cell per well) using the autocloning unit of an EPICS-V cell sorter. Expansion of such cells (with IL-2 and heavily...... irradiated autologous thymocytes as feeder cells) resulted in growth in 6-14% of the wells (mean, 11%) with cells with mature T lymphocyte phenotype. Two-color fluorescence analysis of outgrowing cultures furthermore ascertained that these cells had differentiated through a phase of simultaneous expression...... of T4 and T8 antigens and at the same time expression of the thymocyte-associated T6 antigens. Thus, given the fact that 10-20% of T cell acute lymphoblastic leukemia (T-ALLs) are CALLA+, we have been able to identify a human prethymic T lymphocyte population that might be the normal counterpart...

  6. Antitumor effect of triptolide in T-cell lymphoblastic lymphoma by inhibiting cell viability, invasion, and epithelial–mesenchymal transition via regulating the PI3K/AKT/mTOR pathway

    Directory of Open Access Journals (Sweden)

    Huang Y

    2018-02-01

    Full Text Available Yan Huang, Sun Wu, Yuan Zhang, Lihua Wang, Yan Guo Department of Hematology, The First Affiliated Hospital of Xinxiang Medical University, Xinxiang, People’s Republic of China Introduction: T-cell lymphoblastic lymphoma (T-LBL is a widely disseminated disease worldwide. Triptolide (TPL is purified from Chinese herb and displays anti-inflammatory, anti-fertility, anti-tumor and immunosuppressive effects. Materials and methods: Here, in vitro and in vivo experiments were conducted to investigate the anti-tumor effect of TPL treatment in T-LBL and the potential mechanism in T-LBL progression. Results: TPL inhibited cell proliferation of T-LBL cells (Jurkat cells and Molt-3 cells in a dose-dependent manner. Flow cytometry analysis showed that cell apoptosis rate was increased by TPL treatment. TPL also up-regulated the expression of Caspase-3, Bax and down-regulated the expression of Bcl-2, indicating that TPL promoted apoptosis in Jurkat cells. Moreover, TPL inhibited invasion ability of Jurkat cells and down-regulated the expression of MMP-3 and MMP-9 in a dose-dependent manner. The expression of Snail, Slug, Twist and Integrin αVβ6 was decreased and the expression of E-cadherin was increased by TPL treatment, indicating that TPL inhibited EMT of Jurkat cells. Apart from that, TPL treatment attenuated the phoslevels of PI3K, Akt and mTOR and suppressed AKT activation compared with control group, suggesting that TPL inhibited PI3K/Akt/mTOR signal pathway in T-LBL. In vivo experiments showed that TPL inhibited tumor growth of T-LBL and promoted apoptosis of tumor cells. The expression of PCNA, Bcl-2, Snail, p-PI3K, p-Akt and mTOR was suppressed by TPL in a dose-dependent manner, suggesting that TPL suppressed tumor growth and promoted apoptosis of tumor cells by inhibiting PI3K/Akt/mTOR signal pathway in T-LBL. Conclusion: In conclusion, TPL exerted anti-tumor effect in T-LBL by inhibiting cell viability, invasion and EMT via regulating the PI3K

  7. Expression of Nanog gene promotes NIH3T3 cell proliferation

    International Nuclear Information System (INIS)

    Zhang Jingyu; Wang Xia; Chen Bing; Suo Guangli; Zhao Yanhong; Duan Ziyuan; Dai Jianwu

    2005-01-01

    Cells are the functional elements in tissue engineering and regenerative medicine. A large number of cells are usually needed for these purposes. However, there are numbers of limitations for in vitro cell proliferation. Nanog is an important self-renewal determinant in embryonic stem cells. However, it remains unknown whether Nanog will influence the cell cycle and cell proliferation of mature cells. In this study, we expressed Nanog in NIH3T3 cells and showed that expression of Nanog in NIH3T3 promoted cells to enter into S phase and enhanced cell proliferation. This suggests that Nanog gene might function in a similar fashion in mature cells as in ES cells. In addition, it may provide an approach for in vitro cell expansion

  8. Human HMGA2 protein overexpressed in mice induces precursor T-cell lymphoblastic leukemia

    International Nuclear Information System (INIS)

    Efanov, A; Zanesi, N; Coppola, V; Nuovo, G; Bolon, B; Wernicle-Jameson, D; Lagana, A; Hansjuerg, A; Pichiorri, F; Croce, C M

    2014-01-01

    T-cell acute lymphoblastic leukemia (T-ALL) is a neoplasia of thymocytes characterized by the rapid accumulation of the precursors of T lymphocytes. HMGA2 (high-mobility group AT-hook 2) gene expression is extremely low in normal adult tissues, but it is overexpressed in many tumors. To identify the biological function of HMGA2, we generated transgenic mice carrying the human HMGA2 gene under control of the V H promoter/Eμ enhancer. Approximately 90% of Eμ-HMGA2 transgenic mice became visibly sick between 4 and 8 months due to the onset and progression of a T-ALL-like disease. Characteristic features included severe alopecia (30% of mice); enlarged lymph nodes and spleen; and profound immunological abnormalities (altered cytokine levels, hypoimmunoglobulinemia) leading to reduced immune responsiveness. Immunophenotyping showed accumulation of CD5+CD4+, CD5+CD8+ or CD5+CD8+CD4+ T-cell populations in the spleens and bone marrow of sick animals. These findings show that HMGA2-driven leukemia in mice closely resembles spontaneous human T-ALL, indicating that HMGA2 transgenic mice should serve as an important model for investigating basic mechanisms and potential new therapies of relevance to human T-ALL

  9. [Regulatory T cells inhibit proliferation of mouse lymphoma cell line EL4 in vitro].

    Science.gov (United States)

    Zhang, Chen; Kong, Yan; Guo, Jun; Ying, Zhi-Tao; Yuan, Zhi-Hong; Zhang, Yun-Tao; Zheng, Wen; Song, Yu-Qin; Li, Ping-Ping; Zhu, Jun

    2010-10-01

    This study was aimed to investigate the effect of regulatory T (Treg) cells on the T cell lymphoma EL4 cells and its mechanism in vitro. C57BL/6 mouse Treg cells were isolated by magnetic cell sorting (MACS). The purity of Treg cells and their expression of Foxp3 were identified by flow cytometry (FCM) and PT-PCR respectively. The suppression of Treg cells on EL4 cells was detected by 3H-TdR method. At the same time, enzyme-linked immunosorbent assay (ELISA) was used to detect the secretion of cytokine TGF-β1 and IL-10. The results showed that CD4+CD25+ T cells could be successfully isolated by MACS with the purity reaching 94.52% and the expression of Foxp3 reaching 84.72%. After sorting, the expression of Foxp3 mRNA could be detected by RT-PCR. 3H-TdR assay confirmed that regulatory T cells could suppress the proliferation of EL4 cells with or without antigen presenting cells (APC) or dendritic cells (DC), APC or DC might effectively enhance the suppression. In addition, DC alone also suppressed the proliferation. TGF-β1 and IL-10 could be detected in the supernatant by ELISA. It is concluded that the Treg cells can obviously suppress the proliferation of T cell lymphoma cells in vitro, APC or DC can enhance this suppressive effect, while the DC alone also can suppress the proliferation of EL4 cells, the TGF-β1 and IL-10 cytokine pathway may be one of the mechanisms of suppression.

  10. Children with acute lymphoblastic leukemia show high numbers of CD4+ and CD8+ T-cells which are reduced by conventional chemotherapy

    OpenAIRE

    Mohamed Labib Salem; Mohamed Ramadan El-Shanshory; Nabila Ibrahim El-Desouki; Said Hammad Abdou; Mohamed Attia Attia; Abdel-Aziz Awad Zidan; Shymaa Sobhy Mourad

    2015-01-01

    Background: Acute lymphoblastic leukemia (ALL) is considered as one of the most common cancer in pediatric malignancies. Among ALL, B-cell Acute Lymphoblastic Leukemia (B-ALL) represents 80% to 85% of the childhood ALL. Problem: Although anti B-ALL chemotherapy kill B-ALL, it associates with alteration in the numbers of CD4+ and CD8+ T-cells, and thus impacts the overall immunity. Aim: To evaluate the impact of anti B-ALL on the numbers of CD4+ and CD8+ T-cells in correlation to the n...

  11. Proliferation-linked apoptosis of adoptively transferred T cells after IL-15 administration in macaques.

    Directory of Open Access Journals (Sweden)

    Carolina Berger

    Full Text Available The adoptive transfer of antigen-specific effector T cells is being used to treat human infections and malignancy. T cell persistence is a prerequisite for therapeutic efficacy, but reliably establishing a high-level and durable T cell response by transferring cultured CD8(+ T cells remains challenging. Thus, strategies that promote a transferred high-level T cell response may improve the efficacy of T cell therapy. Lymphodepletion enhances persistence of transferred T cells in mice in part by reducing competition for IL-15, a common γ-chain cytokine that promotes T cell memory, but lymphodepleting regimens have toxicity. IL-15 can be safely administered and has minimal effects on CD4(+ regulatory T cells at low doses, making it an attractive adjunct in adoptive T cell therapy. Here, we show in lymphoreplete macaca nemestrina, that proliferation of adoptively transferred central memory-derived CD8(+ effector T (T(CM/E cells is enhanced in vivo by administering IL-15. T(CM/E cells migrated to memory niches, persisted, and acquired both central memory and effector memory phenotypes regardless of the cytokine treatment. Unexpectedly, despite maintaining T cell proliferation, IL-15 did not augment the magnitude of the transferred T cell response in blood, bone marrow, or lymph nodes. T cells induced to proliferate by IL-15 displayed increased apoptosis demonstrating that enhanced cycling was balanced by cell death. These results suggest that homeostatic mechanisms that regulate T cell numbers may interfere with strategies to augment a high-level T cell response by adoptive transfer of CD8(+ T(CM/E cells in lymphoreplete hosts.

  12. Successful Treatment of Fanconi Anemia and T-Cell Acute Lymphoblastic Leukemia

    Directory of Open Access Journals (Sweden)

    Terrie Flatt

    2012-01-01

    Full Text Available Fanconi anemia is associated with an increased risk of malignancy. Patients are sensitive to the toxic effects of chemotherapy. We report the case of a patient with Fanconi anemia who developed T-cell acute lymphoblastic leukemia. He experienced chemotherapy-related complications including prolonged neutropenia, grade IV vincristine neuropathy, and disseminated aspergillosis. He was successfully treated with modified dosing of cytarabine and intrathecal methotrexate followed by allogeneic bone marrow transplant. The aspergillosis was treated with systemic antifungal treatment and surgical resection. Now 30 months after bone marrow transplant the patient is without evidence of aspergillosis or leukemia.

  13. Transient Responses to NOTCH and TLX1/HOX11 Inhibition in T-Cell Acute Lymphoblastic Leukemia/Lymphoma

    OpenAIRE

    Rakowski, Lesley A.; Lehotzky, Erica A.; Chiang, Mark Y.

    2011-01-01

    To improve the treatment strategies of T-cell acute lymphoblastic leukemia/lymphoma (T-ALL), further efforts are needed to identify therapeutic targets. Dysregulated expression of HOX-type transcription factors occurs in 30-40% of cases of T-ALL. TLX1/HOX11 is the prototypical HOX-type transcription factor. TLX1 may be an attractive therapeutic target because mice that are deficient in TLX1 are healthy. To test this possibility, we developed a conditional doxycycline-regulated mouse model of ...

  14. Blockade of CD7 expression in T cells for effective chimeric antigen receptor targeting of T-cell malignancies.

    Science.gov (United States)

    Png, Yi Tian; Vinanica, Natasha; Kamiya, Takahiro; Shimasaki, Noriko; Coustan-Smith, Elaine; Campana, Dario

    2017-11-28

    Effective immunotherapies for T-cell malignancies are lacking. We devised a novel approach based on chimeric antigen receptor (CAR)-redirected T lymphocytes. We selected CD7 as a target because of its consistent expression in T-cell acute lymphoblastic leukemia (T-ALL), including the most aggressive subtype, early T-cell precursor (ETP)-ALL. In 49 diagnostic T-ALL samples (including 14 ETP-ALL samples), median CD7 expression was >99%; CD7 expression remained high at relapse (n = 14), and during chemotherapy (n = 54). We targeted CD7 with a second-generation CAR (anti-CD7-41BB-CD3ζ), but CAR expression in T lymphocytes caused fratricide due to the presence of CD7 in the T cells themselves. To downregulate CD7 and control fratricide, we applied a new method (protein expression blocker [PEBL]), based on an anti-CD7 single-chain variable fragment coupled with an intracellular retention domain. Transduction of anti-CD7 PEBL resulted in virtually instantaneous abrogation of surface CD7 expression in all transduced T cells; 2.0% ± 1.7% were CD7 + vs 98.1% ± 1.5% of mock-transduced T cells (n = 5; P < .0001). PEBL expression did not impair T-cell proliferation, interferon-γ and tumor necrosis factor-α secretion, or cytotoxicity, and eliminated CAR-mediated fratricide. PEBL-CAR T cells were highly cytotoxic against CD7 + leukemic cells in vitro and were consistently more potent than CD7 + T cells spared by fratricide. They also showed strong anti-leukemic activity in cell line- and patient-derived T-ALL xenografts. The strategy described in this study fits well with existing clinical-grade cell manufacturing processes and can be rapidly implemented for the treatment of patients with high-risk T-cell malignancies.

  15. Influence of age on the proliferation and peripheralization of thymic T cells

    International Nuclear Information System (INIS)

    Hirokawa, K.; Utsuyama, M.; Katsura, Y.; Sado, T.

    1988-01-01

    Bone marrow cells obtained from B10.Thy-1.1 mice (H-2b, Thy-1.1) were injected directly into the thymus of C57BL/6 mice (H-2b,Thy 1.2) of various ages. Thymocyte precursors in the injected donor-bone marrow cells could proliferate in the thymic microenvironment in the following manner: first, preferentially proliferating into the subcapsular cortex; and second, spreading to the whole layer of the cortex, a portion of them gradually moving into the medulla. The proliferation of donor-type thymocytes was most pronounced when intrathymic injection of bone marrow cells (ITB) was performed in newborn mice and especially prominent in week-old mice; it took approximately ten weeks for donor-type thymocytes to finish the whole course of proliferation, differentiation, and emigration to the periphery. When ITB was performed in mice 4 weeks of age and older, the proliferation of donor-type thymocytes was retarded at onset, less pronounced in magnitude, and disappeared earlier. Emigration of donor-type T cells from the thymus to the peripheral lymphoid tissues occurred most rapidly when ITB was performed in newborn mice, and these T cells continued to reside thereafter in the peripheral lymphoid tissues. However, when ITB was performed in mice 4 weeks of age and older, the number of emigrated T cells in the spleen decreased (about a tenth of that in newborn mice) and, moreover, these T cells resided only transiently in the spleen. It was suggested that T cells emigrating from the thymus of mice from newborn to 2 weeks of age are long-lived, whereas those from the thymus in mice 4 weeks of age and older are short-lived. However, when 4-week-old young adult mice were treated by irradiation or hydrocortisone, the thymic capacity was enhanced in terms of proliferation and peripheralization of thymocytes, and emigrated T cells became long-lived

  16. Psoriatic T cells reduce epidermal turnover time and affect cell proliferation contributed from differential gene expression.

    Science.gov (United States)

    Li, Junqin; Li, Xinhua; Hou, Ruixia; Liu, Ruifeng; Zhao, Xincheng; Dong, Feng; Wang, Chunfang; Yin, Guohua; Zhang, Kaiming

    2015-09-01

    Psoriasis is mediated primarily by T cells, which reduce epidermal turnover time and affect keratinocyte proliferation. We aimed to identify differentially expressed genes (DEG) in T cells from normal, five pairs of monozygotic twins concordant or discordant for psoriasis, to determine whether these DEG may account for the influence to epidermal turnover time and keratinocyte proliferation. The impact of T cells on keratinocyte proliferation and epidermal turnover time were investigated separately by immunohistochemistry and cultured with (3) H-TdR. mRNA expression patterns were investigated by RNA sequencing and verified by real-time reverse transcription polymerase chain reaction. After co-culture with psoriatic T cells, the expression of Ki-67, c-Myc and p53 increased, while expression of Bcl-2 and epidermal turnover time decreased. There were 14 DEG which were found to participate in the regulation of cell proliferation or differentiation. Psoriatic T cells exhibited the ability to decrease epidermal turnover time and affect keratinocyte proliferation because of the differential expression of PPIL1, HSPH1, SENP3, NUP54, FABP5, PLEKHG3, SLC9A9 and CHCHD4. © 2015 Japanese Dermatological Association.

  17. Trigeminal nerve involvement in T-cell acute lymphoblastic leukemia: value of MR imaging

    Energy Technology Data Exchange (ETDEWEB)

    Karadag, Demet; Karaguelle, Ayse Tuba; Erden, Ilhan; Erden, Ayse E-mail: erden@ada.net.tr

    2002-10-01

    A 30-year-old male with T-cell acute lymphoblastic leukemia presented with facial numbness. Neurological examination revealed paresthesia of the left trigeminal nerve. Cerebrospinal fluid (CSF) cytology showed no atypical cells. Gadolinium-enhanced magnetic resonance (MR) imaging demonstrated enlargement and enhancement of intracranial portions of the left trigeminal nerve. The abnormal MR imaging findings almost completely resolved after the chemotherapy. Gadolinium-enhanced MR imaging is not only a useful procedure for the early diagnosis of cranial nerve invasion by leukemia but it might be helpful to follow the changes after the treatment.

  18. Promoter DNA methylation pattern identifies prognostic subgroups in childhood T-cell acute lymphoblastic leukemia.

    Directory of Open Access Journals (Sweden)

    Magnus Borssén

    Full Text Available BACKGROUND: Treatment of pediatric T-cell acute lymphoblastic leukemia (T-ALL has improved, but there is a considerable fraction of patients experiencing a poor outcome. There is a need for better prognostic markers and aberrant DNA methylation is a candidate in other malignancies, but its potential prognostic significance in T-ALL is hitherto undecided. DESIGN AND METHODS: Genome wide promoter DNA methylation analysis was performed in pediatric T-ALL samples (n = 43 using arrays covering >27000 CpG sites. Clinical outcome was evaluated in relation to methylation status and compared with a contemporary T-ALL group not tested for methylation (n = 32. RESULTS: Based on CpG island methylator phenotype (CIMP, T-ALL samples were subgrouped as CIMP+ (high methylation and CIMP- (low methylation. CIMP- T-ALL patients had significantly worse overall and event free survival (p = 0.02 and p = 0.001, respectively compared to CIMP+ cases. CIMP status was an independent factor for survival in multivariate analysis including age, gender and white blood cell count. Analysis of differently methylated genes in the CIMP subgroups showed an overrepresentation of transcription factors, ligands and polycomb target genes. CONCLUSIONS: We identified global promoter methylation profiling as being of relevance for subgrouping and prognostication of pediatric T-ALL.

  19. TLX1 and NOTCH coregulate transcription in T cell acute lymphoblastic leukemia cells

    Directory of Open Access Journals (Sweden)

    Lee Norman H

    2010-07-01

    Full Text Available Abstract Background The homeobox gene TLX1 (for T-cell leukemia homeobox 1, previously known as HOX11 is inappropriately expressed in a major subgroup of T cell acute lymphoblastic leukemia (T-ALL where it is strongly associated with activating NOTCH1 mutations. Despite the recognition that these genetic lesions cooperate in leukemogenesis, there have been no mechanistic studies addressing how TLX1 and NOTCH1 functionally interact to promote the leukemic phenotype. Results Global gene expression profiling after downregulation of TLX1 and inhibition of the NOTCH pathway in ALL-SIL cells revealed that TLX1 synergistically regulated more than 60% of the NOTCH-responsive genes. Structure-function analysis demonstrated that TLX1 binding to Groucho-related TLE corepressors was necessary for maximal transcriptional regulation of the NOTCH-responsive genes tested, implicating TLX1 modulation of the NOTCH-TLE regulatory network. Comparison of the dataset to publicly available biological databases indicated that the TLX1/NOTCH-coregulated genes are frequently targeted by MYC. Gain- and loss-of-function experiments confirmed that MYC was an essential mediator of TLX1/NOTCH transcriptional output and growth promotion in ALL-SIL cells, with TLX1 contributing to the NOTCH-MYC regulatory axis by posttranscriptional enhancement of MYC protein levels. Functional classification of the TLX1/NOTCH-coregulated targets also showed enrichment for genes associated with other human cancers as well as those involved in developmental processes. In particular, we found that TLX1, NOTCH and MYC coregulate CD1B and RAG1, characteristic markers of early cortical thymocytes, and that concerted downregulation of the TLX1 and NOTCH pathways resulted in their irreversible repression. Conclusions We found that TLX1 and NOTCH synergistically regulate transcription in T-ALL, at least in part via the sharing of a TLE corepressor and by augmenting expression of MYC. We conclude that

  20. An early thymic precursor phenotype predicts outcome exclusively in HOXA-overexpressing adult T-cell acute lymphoblastic leukemia: a Group for Research in Adult Acute Lymphoblastic Leukemia study.

    Science.gov (United States)

    Bond, Jonathan; Marchand, Tony; Touzart, Aurore; Cieslak, Agata; Trinquand, Amélie; Sutton, Laurent; Radford-Weiss, Isabelle; Lhermitte, Ludovic; Spicuglia, Salvatore; Dombret, Hervé; Macintyre, Elizabeth; Ifrah, Norbert; Hamel, Jean-François; Asnafi, Vahid

    2016-06-01

    Gene expression studies have consistently identified a HOXA-overexpressing cluster of T-cell acute lymphoblastic leukemias, but it is unclear whether these constitute a homogeneous clinical entity, and the biological consequences of HOXA overexpression have not been systematically examined. We characterized the biology and outcome of 55 HOXA-positive cases among 209 patients with adult T-cell acute lymphoblastic leukemia uniformly treated during the Group for Research on Adult Acute Lymphoblastic Leukemia (GRAALL)-2003 and -2005 studies. HOXA-positive patients had markedly higher rates of an early thymic precursor-like immunophenotype (40.8% versus 14.5%, P=0.0004), chemoresistance (59.3% versus 40.8%, P=0.026) and positivity for minimal residual disease (48.5% versus 23.5%, P=0.01) than the HOXA-negative group. These differences were due to particularly high frequencies of chemoresistant early thymic precursor-like acute lymphoblastic leukemia in HOXA-positive cases harboring fusion oncoproteins that transactivate HOXA Strikingly, the presence of an early thymic precursor-like immunophenotype was associated with marked outcome differences within the HOXA-positive group (5-year overall survival 31.2% in HOXA-positive early thymic precursor versus 66.7% in HOXA-positive non-early thymic precursor, P=0.03), but not in HOXA-negative cases (5-year overall survival 74.2% in HOXA-negative early thymic precursor versus 57.2% in HOXA-negative non-early thymic precursor, P=0.44). Multivariate analysis further revealed that HOXA positivity independently affected event-free survival (P=0.053) and relapse risk (P=0.039) of chemoresistant T-cell acute lymphoblastic leukemia. These results show that the underlying mechanism of HOXA deregulation dictates the clinico-biological phenotype, and that the negative prognosis of early thymic precursor acute lymphoblastic leukemia is exclusive to HOXA-positive patients, suggesting that early treatment intensification is currently

  1. CD19-Targeted CAR T cells as novel cancer immunotherapy for relapsed or refractory B-cell acute lymphoblastic leukemia.

    Science.gov (United States)

    Davila, Marco L; Brentjens, Renier J

    2016-10-01

    Immunotherapy has demonstrated significant potential for the treatment of patients with chemotherapy-resistant hematologic malignancies and solid tumors. One type of immunotherapy involves the adoptive transfer of T cells that have been genetically modified with a chimeric antigen receptor (CAR) to target a tumor. These hybrid proteins are composed of the antigen-binding domains of an antibody fused to T-cell receptor signaling machinery. CAR T cells that target CD19 recently have made the jump from the laboratory to the clinic, and the results have been remarkable. CD19-targeted CAR T cells have induced complete remissions of disease in up to 90% of patients with relapsed or refractory B-cell acute lymphoblastic leukemia (B-ALL), who have an expected complete response rate of 30% in response to chemotherapy. The high efficacy of CAR T cells in B-ALL suggests that regulatory approval of this therapy for this routinely fatal leukemia is on the horizon. We review the preclinical development of CAR T cells and their early clinical application for lymphoma. We also provide a comprehensive analysis of the use of CAR T cells in patients with B-ALL. In addition, we discuss the unique toxicities associated with this therapy and the management schemes that have been developed.

  2. TCR/CD3 ligation of a TCR-transgenic T lymphoma blocks its proliferation in vitro but does not affect its growth in vivo

    DEFF Research Database (Denmark)

    Reimann, J; Rudolphi, A; Tcherepnev, G

    1994-01-01

    A backcrossed mouse line was established homozygous for the autosomal recessive mutation scid (severe combined immunodeficiency) and carrying T cells which express transgenic (tg) T cell receptor (TCR) alpha and beta chains that mediate H-2 class I (Db)-restricted recognition of a male (H...... of TL1 cells resembled that of small-to-medium lymphoblasts. The cells had the following phenotype: CD3 + TCR alpha T+TCR beta T+CD4-CD8- CD44-CD45RB+LECAM-1 + IL-2R- and low H-2 expression. Exposure of TL1 cells to TCR-binding monoclonal antibodies or lectins blocked in their in vitro proliferation...

  3. Core Transcriptional Regulatory Circuit Controlled by the TAL1 Complex in Human T Cell Acute Lymphoblastic Leukemia

    OpenAIRE

    Sanda, Takaomi; Lawton, Lee N.; Barrasa, M. Inmaculada; Fan, Zi Peng; Kohlhammer, Holger; Gutierrez, Alejandro; Ma, Wenxue; Tatarek, Jessica; Ahn, Yebin; Kelliher, Michelle A.; Jamieson, Catriona H.M.; Staudt, Louis M.; Young, Richard A.; Look, A. Thomas

    2012-01-01

    The oncogenic transcription factor TAL1/SCL is aberrantly expressed in over 40% of cases of human T-cell acute lymphoblastic leukemia (T-ALL), emphasizing its importance in the molecular pathogenesis of T-ALL. Here we identify the core transcriptional regulatory circuit controlled by TAL1 and its regulatory partners HEB, E2A, LMO1/2, GATA3 and RUNX1. We show that TAL1 forms a positive interconnected auto-regulatory loop with GATA3 and RUNX1, and that the TAL1 complex directly activates the MY...

  4. Human retinal pigment epithelial cells inhibit proliferation and IL2R expression of activated T cells

    DEFF Research Database (Denmark)

    Kaestel, Charlotte G; Jørgensen, Annette; Nielsen, Mette

    2002-01-01

    -Thymidine incorporation assay, respectively. T cells and RPE cells were cultured directly together or in a transwell system for determination of the effect of cell contact. The importance of cell surface molecules was examined by application of a panel of blocking antibodies (CD2, CD18, CD40, CD40L, CD54, CD58......) in addition to use of TCR negative T cell lines. The expression of IL2R-alpha -beta and -gamma chains of activated T cells was analysed by flow cytometry after incubation of T cells alone or with RPE cells. Human RPE cells were found to inhibit the proliferation of activated T cells by a cell contact......-beta and -gamma chain expression within 24 hr after removal from the coculture. It is concluded that the cultured human adult and foetal RPE cells inhibit the proliferation of activated T cells by a process that does not involve apoptosis. It depends on cell contact but the involved surface molecules were...

  5. Lactobacillus paracasei subsp. paracasei B21060 suppresses human T-cell proliferation.

    Science.gov (United States)

    Peluso, Ilaria; Fina, Daniele; Caruso, Roberta; Stolfi, Carmine; Caprioli, Flavio; Fantini, Massimo Claudio; Caspani, Giorgio; Grossi, Enzo; Di Iorio, Laura; Paone, Francesco Maria; Pallone, Francesco; Monteleone, Giovanni

    2007-04-01

    Recent studies have shown that probiotics are beneficial in T-cell-mediated inflammatory diseases. The molecular mechanism by which probiotics work remains elusive, but accumulating evidence indicates that probiotics can modulate immune cell responses. Since T cells express receptors for bacterial products or components, we examined whether different strains of lactobacilli directly regulate the functions of human T cells. CD4(+) T cells were isolated from blood and intestinal lamina propria (LP) of normal individuals and patients with inflammatory bowel disease (IBD). Mononuclear cells were also isolated from Peyer's patches. Cells were activated with anti-CD3/CD2/CD28 in the presence or absence of Lactobacillus paracasei subsp. paracasei B21060, L. paracasei subsp. paracasei F19, or L. casei subsp. casei DG. Cell proliferation and death, Foxp3, intracellular pH, and cytokine production were evaluated by flow cytometry. We showed that L. paracasei subsp. paracasei B21060 but neither L. paracasei subsp. paracasei F19 nor L. casei subsp. casei DG inhibited blood CD4(+) T-cell growth. This effect was associated with no change in cell survival, expression of Foxp3, or production of gamma interferon, interleukin-4 (IL-4), IL-5, and IL-10. L. paracasei subsp. paracasei B21060-mediated blockade of CD4(+) T-cell proliferation required a viable bacterium and was associated with decreased MCT-1 expression and low intracellular pH. L. paracasei subsp. paracasei B21060 also inhibited the growth of Peyer's patch mononuclear cells, normal lymphocytes, and IBD CD4(+) LP lymphocytes without affecting cytokine production. The data show that L. paracasei subsp. paracasei B21060 blocks T-cell growth, thus suggesting a mechanism by which these probiotics could interfere with T-cell-driven immune responses.

  6. Adaptive Immunity to Leukemia Is Inhibited by Cross-Reactive Induced Regulatory T Cells.

    Science.gov (United States)

    Manlove, Luke S; Berquam-Vrieze, Katherine E; Pauken, Kristen E; Williams, Richard T; Jenkins, Marc K; Farrar, Michael A

    2015-10-15

    BCR-ABL(+) acute lymphoblastic leukemia patients have transient responses to current therapies. However, the fusion of BCR to ABL generates a potential leukemia-specific Ag that could be a target for immunotherapy. We demonstrate that the immune system can limit BCR-ABL(+) leukemia progression although ultimately this immune response fails. To address how BCR-ABL(+) leukemia escapes immune surveillance, we developed a peptide: MHC class II tetramer that labels endogenous BCR-ABL-specific CD4(+) T cells. Naive mice harbored a small population of BCR-ABL-specific T cells that proliferated modestly upon immunization. The small number of naive BCR-ABL-specific T cells was due to negative selection in the thymus, which depleted BCR-ABL-specific T cells. Consistent with this observation, we saw that BCR-ABL-specific T cells were cross-reactive with an endogenous peptide derived from ABL. Despite this cross-reactivity, the remaining population of BCR-ABL reactive T cells proliferated upon immunization with the BCR-ABL fusion peptide and adjuvant. In response to BCR-ABL(+) leukemia, BCR-ABL-specific T cells proliferated and converted into regulatory T (Treg) cells, a process that was dependent on cross-reactivity with self-antigen, TGF-β1, and MHC class II Ag presentation by leukemic cells. Treg cells were critical for leukemia progression in C57BL/6 mice, as transient Treg cell ablation led to extended survival of leukemic mice. Thus, BCR-ABL(+) leukemia actively suppresses antileukemia immune responses by converting cross-reactive leukemia-specific T cells into Treg cells. Copyright © 2015 by The American Association of Immunologists, Inc.

  7. Donor lung derived myeloid and plasmacytoid dendritic cells differentially regulate T cell proliferation and cytokine production

    Directory of Open Access Journals (Sweden)

    Benson Heather L

    2012-03-01

    Full Text Available Abstract Background Direct allorecognition, i.e., donor lung-derived dendritic cells (DCs stimulating recipient-derived T lymphocytes, is believed to be the key mechanism of lung allograft rejection. Myeloid (cDCs and plasmacytoid (pDCs are believed to have differential effects on T cell activation. However, the roles of each DC type on T cell activation and rejection pathology post lung transplantation are unknown. Methods Using transgenic mice and antibody depletion techniques, either or both cell types were depleted in lungs of donor BALB/c mice (H-2d prior to transplanting into C57BL/6 mice (H-2b, followed by an assessment of rejection pathology, and pDC or cDC-induced proliferation and cytokine production in C57BL/6-derived mediastinal lymph node T cells (CD3+. Results Depleting either DC type had modest effect on rejection pathology and T cell proliferation. In contrast, T cells from mice that received grafts depleted of both DCs did not proliferate and this was associated with significantly reduced acute rejection scores compared to all other groups. cDCs were potent inducers of IFNγ, whereas both cDCs and pDCs induced IL-10. Both cell types had variable effects on IL-17A production. Conclusion Collectively, the data show that direct allorecognition by donor lung pDCs and cDCs have differential effects on T cell proliferation and cytokine production. Depletion of both donor lung cDC and pDC could prevent the severity of acute rejection episodes.

  8. MicroRNA181a Is Overexpressed in T-Cell Leukemia/Lymphoma and Related to Chemoresistance

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    Zi-Xun Yan

    2015-01-01

    Full Text Available MicroRNAs (miRs play an important role in tumorogenesis and chemoresistance in lymphoid malignancies. Comparing with reactive hyperplasia, miR181a was overexpressed in 130 patients with T-cell leukemia/lymphoma, including acute T-cell lymphoblastic leukemia (n=32, T-cell lymphoblastic lymphoma (n=16, peripheral T-cell lymphoma, not otherwise specified (n=45, anaplastic large cell lymphoma (n=15, and angioimmunoblastic T-cell lymphoma (n=22. Irrespective to histological subtypes, miR181a overexpression was associated with increased AKT phosphorylation. In vitro, ectopic expression of miR181a in HEK-293T cells significantly enhanced cell proliferation, activated AKT, and conferred cell resistance to doxorubicin. Meanwhile, miR181a expression was upregulated in Jurkat cells, along with AKT activation, during exposure to chemotherapeutic agents regularly applied to T-cell leukemia/lymphoma treatment, such as doxorubicin, cyclophosphamide, cytarabine, and cisplatin. Isogenic doxorubicin-resistant Jurkat and H9 cells were subsequently developed, which also presented with miR181a overexpression and cross-resistance to cyclophosphamide and cisplatin. Meanwhile, specific inhibition of miR181a enhanced Jurkat and H9 cell sensitivity to chemotherapeutic agents, further indicating that miR181a was involved in acquired chemoresistance. Collectively, miR181a functioned as a biomarker of T-cell leukemia/lymphoma through modulation of AKT pathway. Related to tumor cell chemoresistance, miR181a could be a potential therapeutic target in treating T-cell malignancies.

  9. Distribution of adoptively transferred porcine T-lymphoblasts tracked by 18F-2-fluoro-2-deoxy-D-glucose and position emission tomography

    International Nuclear Information System (INIS)

    Eriksson, Olof; Sadeghi, Arian; Carlsson, Bjoern; Eich, Torsten; Lundgren, Torbjoern; Nilsson, Bo; Toetterman, Thomas; Korsgren, Olle; Sundin, Anders

    2011-01-01

    Introduction: Autologous or allogeneic transfer of tumor-infiltrating T-lymphocytes is a promising treatment for metastatic cancers, but a major concern is the difficulty in evaluating cell trafficking and distribution in adoptive cell therapy. This study presents a method of tracking transfusion of T-lymphoblasts in a porcine model by 18 F-2-fluoro-2-deoxy-D-glucose ([ 18 F]FDG) and positron emission tomography. Methods: T-lymphoblasts were labeled with the positron-emitting tracer [ 18 F]FDG through incubation. The T-lymphoblasts were administered into the bloodstream, and the distribution was followed by positron emission tomography for 120 min. The cells were administered either intravenously into the internal jugular vein (n=5) or intraarterially into the ascending aorta (n=1). Two of the pigs given intravenous administration were pretreated with low-molecular-weight dextran sulphate. Results: The cellular kinetics and distribution were readily quantifiable for up to 120 min. High (78.6% of the administered cells) heterogeneous pulmonary uptake was found after completed intravenous transfusion. The pulmonary uptake was decreased either by preincubating and coadministrating the T-lymphoblasts with low-molecular-weight dextran sulphate or by administrating them intraarterially. Conclusions: The present work shows the feasibility of quantitatively monitoring and evaluating cell trafficking and distribution following administration of [ 18 F]FDG-labeled T-lymphoblasts. The protocol can potentially be transferred to the clinical setting with few modifications.

  10. Primary T cell central nervous system lymphoblastic lymphoma in a child: case report and literature review.

    Science.gov (United States)

    Mazur, Marcus D; Ravindra, Vijay M; Alashari, Mouied; Raetz, Elizabeth; Poppe, Matthew M; Bollo, Robert J

    2015-06-01

    Primary central nervous system lymphoma (PCNSL) of T cell origin is rare in pediatric patients. We report a case of T cell PCNSL in a 12-year-old boy and review the literature to highlight the importance of brain biopsy to definitively establish the diagnosis when PCNSL is suspected. A 12-year-old boy presented with worsening left-sided weakness, nausea, vomiting, headache, blurred vision, and diplopia. Magnetic resonance imaging revealed right parietal gyral thickening with faint meningeal contrast enhancement. No clear diagnosis was identified after serum testing, cerebrospinal fluid analysis, and cerebral angiography. To establish the diagnosis definitively, a right craniotomy and open, frameless stereotactic biopsy were performed, which yielded the diagnosis of lymphoblastic T cell lymphoma. PCNSL of T cell origin in children remains poorly studied, with only 18 detailed cases reported over the last three decades, including this case. Establishing a definitive diagnosis of PCNSL is challenging, and a brain biopsy is often required to obtain enough tissue for pathological analysis. Increasing awareness and identification of children diagnosed with T cell PCNSL is needed to better understand the molecular biology of this disease and develop more standardized treatment regimens.

  11. Glucocorticoid resistance is reverted by LCK inhibition in pediatric T-cell acute lymphoblastic leukemia.

    Science.gov (United States)

    Serafin, Valentina; Capuzzo, Giorgia; Milani, Gloria; Minuzzo, Sonia Anna; Pinazza, Marica; Bortolozzi, Roberta; Bresolin, Silvia; Porcù, Elena; Frasson, Chiara; Indraccolo, Stefano; Basso, Giuseppe; Accordi, Benedetta

    2017-12-21

    Pediatric T-acute lymphoblastic leukemia (T-ALL) patients often display resistance to glucocorticoid (GC) treatment. These patients, classified as prednisone poor responders (PPR), have poorer outcome than do the other pediatric T-ALL patients receiving a high-risk adapted therapy. Because glucocorticoids are administered to ALL patients during all the different phases of therapy, GC resistance represents an important challenge to improving the outcome for these patients. Mechanisms underlying resistance are not yet fully unraveled; thus our research focused on the identification of deregulated signaling pathways to point out new targeted approaches. We first identified, by reverse-phase protein arrays, the lymphocyte cell-specific protein-tyrosine kinase (LCK) as aberrantly activated in PPR patients. We showed that LCK inhibitors, such as dasatinib, bosutinib, nintedanib, and WH-4-023, are able to induce cell death in GC-resistant T-ALL cells, and remarkably, cotreatment with dexamethasone is able to reverse GC resistance, even at therapeutic drug concentrations. This was confirmed by specific LCK gene silencing and ex vivo combined treatment of cells from PPR patient-derived xenografts. Moreover, we observed that LCK hyperactivation in PPR patients upregulates the calcineurin/nuclear factor of activated T cells signaling triggering to interleukin-4 ( IL-4 ) overexpression. GC-sensitive cells cultured with IL-4 display an increased resistance to dexamethasone, whereas the inhibition of IL-4 signaling could increase GC-induced apoptosis in resistant cells. Treatment with dexamethasone and dasatinib also impaired engraftment of leukemia cells in vivo. Our results suggest a quickly actionable approach to supporting conventional therapies and overcoming GC resistance in pediatric T-ALL patients. © 2017 by The American Society of Hematology.

  12. The effect of stem cell from human exfoliated deciduous teeth on T lymphocyte proliferation.

    Science.gov (United States)

    Alipour, Razieh; Adib, Minoo; Hashemi-Beni, Batool; Sadeghi, Farzaneh

    2014-01-01

    Mesenchymal stem cells (MSC), a specific type of adult tissue stem cell; have the immunosuppressive effects that make them valuable targets for regenerative medicine and treatment of many human illnesses. Hence, MSC have been the subject of numerous studies. The classical source of MSC is adult bone marrow (BM). Due to many shortcomings of harvesting MSC from BM, finding the alternative sources for MSC is an urgent. Stem cells from human exfoliated deciduous teeth (SHED) are relative new MSC populations that fulfill these criteria but their potential immunosuppressive effect has not been studied enough yet. Thus, in this work the effect of SHED on the proliferation of in vitro activated T lymphocytes were explored. In this study, both mitogen and alloantigen activated T cells were cultured in the presence of different numbers of SHED. In some co-cultures, activated T cells were in direct contact to MSCs and in other co-cultures; they were separated from SHED by a permeable membrane. In all co-cultures, the proliferation of T cells was measured by ELISA Bromodeoxyuridine proliferation assay. In general, our results showed that SHED significantly suppress the proliferation of activated T cells in a dose-dependent manner. Moreover, the suppression was slightly stronger when MSCs were in physical contact to activated T cells. This study showed that SHED likewise other MSC populations can suppress the activation of T lymphocytes, which can be used instead of BM derived MSCs in many investigational and clinical applications.

  13. PDZ domain-binding motif of Tax sustains T-cell proliferation in HTLV-1-infected humanized mice

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    Artesi, Maria; Jalinot, Pierre

    2018-01-01

    Human T-cell leukemia virus type 1 (HTLV-1) is the etiological agent of adult T-cell leukemia/lymphoma (ATLL), an aggressive malignant proliferation of activated CD4+ T lymphocytes. The viral Tax oncoprotein is critically involved in both HTLV-1-replication and T-cell proliferation, a prerequisite to the development of ATLL. In this study, we investigated the in vivo contribution of the Tax PDZ domain-binding motif (PBM) to the lymphoproliferative process. To that aim, we examined T-cell proliferation in humanized mice (hu-mice) carrying a human hemato-lymphoid system infected with either a wild type (WT) or a Tax PBM-deleted (ΔPBM) provirus. We observed that the frequency of CD4+ activated T-cells in the peripheral blood and in the spleen was significantly higher in WT than in ΔPBM hu-mice. Likewise, human T-cells collected from WT hu-mice and cultivated in vitro in presence of interleukin-2 were proliferating at a higher level than those from ΔPBM animals. We next examined the association of Tax with the Scribble PDZ protein, a prominent regulator of T-cell polarity, in human T-cells analyzed either after ex vivo isolation or after in vitro culture. We confirmed the interaction of Tax with Scribble only in T-cells from the WT hu-mice. This association correlated with the presence of both proteins in aggregates at the leading edge of the cells and with the formation of long actin filopods. Finally, data from a comparative genome-wide transcriptomic analysis suggested that the PBM-PDZ association is implicated in the expression of genes regulating proliferation, apoptosis and cytoskeletal organization. Collectively, our findings suggest that the Tax PBM is an auxiliary motif that contributes to the sustained growth of HTLV-1 infected T-cells in vivo and in vitro and is essential to T-cell immortalization. PMID:29566098

  14. PDZ domain-binding motif of Tax sustains T-cell proliferation in HTLV-1-infected humanized mice.

    Science.gov (United States)

    Pérès, Eléonore; Blin, Juliana; Ricci, Emiliano P; Artesi, Maria; Hahaut, Vincent; Van den Broeke, Anne; Corbin, Antoine; Gazzolo, Louis; Ratner, Lee; Jalinot, Pierre; Duc Dodon, Madeleine

    2018-03-01

    Human T-cell leukemia virus type 1 (HTLV-1) is the etiological agent of adult T-cell leukemia/lymphoma (ATLL), an aggressive malignant proliferation of activated CD4+ T lymphocytes. The viral Tax oncoprotein is critically involved in both HTLV-1-replication and T-cell proliferation, a prerequisite to the development of ATLL. In this study, we investigated the in vivo contribution of the Tax PDZ domain-binding motif (PBM) to the lymphoproliferative process. To that aim, we examined T-cell proliferation in humanized mice (hu-mice) carrying a human hemato-lymphoid system infected with either a wild type (WT) or a Tax PBM-deleted (ΔPBM) provirus. We observed that the frequency of CD4+ activated T-cells in the peripheral blood and in the spleen was significantly higher in WT than in ΔPBM hu-mice. Likewise, human T-cells collected from WT hu-mice and cultivated in vitro in presence of interleukin-2 were proliferating at a higher level than those from ΔPBM animals. We next examined the association of Tax with the Scribble PDZ protein, a prominent regulator of T-cell polarity, in human T-cells analyzed either after ex vivo isolation or after in vitro culture. We confirmed the interaction of Tax with Scribble only in T-cells from the WT hu-mice. This association correlated with the presence of both proteins in aggregates at the leading edge of the cells and with the formation of long actin filopods. Finally, data from a comparative genome-wide transcriptomic analysis suggested that the PBM-PDZ association is implicated in the expression of genes regulating proliferation, apoptosis and cytoskeletal organization. Collectively, our findings suggest that the Tax PBM is an auxiliary motif that contributes to the sustained growth of HTLV-1 infected T-cells in vivo and in vitro and is essential to T-cell immortalization.

  15. Fetal calf serum heat inactivation and lipopolysaccharide contamination influence the human T lymphoblast proteome and phosphoproteome

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    Rahman Hazir

    2011-11-01

    Full Text Available Abstract Background The effects of fetal calf serum (FCS heat inactivation and bacterial lipopolysaccharide (LPS contamination on cell physiology have been studied, but their effect on the proteome of cultured cells has yet to be described. This study was undertaken to investigate the effects of heat inactivation of FCS and LPS contamination on the human T lymphoblast proteome. Human T lymphoblastic leukaemia (CCRF-CEM cells were grown in FCS, either non-heated, or heat inactivated, having low ( Results A total of four proteins (EIF3M, PRS7, PSB4, and SNAPA were up-regulated when CCRF-CEM cells were grown in media supplemented with heat inactivated FCS (HE as compared to cells grown in media with non-heated FCS (NHE. Six proteins (TCPD, ACTA, NACA, TCTP, ACTB, and ICLN displayed a differential phosphorylation pattern between the NHE and HE groups. Compared to the low concentration LPS group, regular levels of LPS resulted in the up-regulation of three proteins (SYBF, QCR1, and SUCB1. Conclusion The present study provides new information regarding the effect of FCS heat inactivation and change in FCS-LPS concentration on cellular protein expression, and post-translational modification in human T lymphoblasts. Both heat inactivation and LPS contamination of FCS were shown to modulate the expression and phosphorylation of proteins involved in basic cellular functions, such as protein synthesis, cytoskeleton stability, oxidative stress regulation and apoptosis. Hence, the study emphasizes the need to consider both heat inactivation and LPS contamination of FCS as factors that can influence the T lymphoblast proteome.

  16. Exchange of cytosolic content between T cells and tumor cells activates CD4 T cells and impedes cancer growth.

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    Matthias Hardtke-Wolenski

    Full Text Available BACKGROUND: T cells are known to participate in the response to tumor cells and react with cytotoxicity and cytokine release. At the same time tumors established versatile mechanisms for silencing the immune responses. The interplay is far from being completely understood. In this study we show contacts between tumor cells and lymphocytes revealing novel characteristics in the interaction of T cells and cancer cells in a way not previously described. METHODS/ FINDINGS: Experiments are based on the usage of a hydrophilic fluorescent dye that occurs free in the cytosol and thus transfer of fluorescent cytosol from one cell to the other can be observed using flow cytometry. Tumor cells from cell lines of different origin or primary hepatocellular carcinoma (HCC cells were incubated with lymphocytes from human and mice. This exposure provoked a contact dependent uptake of tumor derived cytosol by lymphocytes--even in CD4⁺ T cells and murine B cells--which could not be detected after incubation of lymphocytes with healthy cells. The interaction was a direct one, not requiring the presence of accessory cells, but independent of cytotoxicity and TCR engagement. Electron microscopy disclosed 100-200 nm large gaps in the cell membranes of connected cells which separated viable and revealed astonishing outcome. While the lymphocytes were induced to proliferate in a long term fashion, the tumor cells underwent a temporary break in cell division. The in vitro results were confirmed in vivo using a murine acute lymphoblastic leukemia (ALL model. The arrest of tumor proliferation resulted in a significant prolonged survival of challenged mice. CONCLUSIONS: The reported cell-cell contacts reveal new characteristics i.e. the enabling of cytosol flow between the cells including biological active proteins that influence the cell cycle and biological behaviour of the recipient cells. This adds a completely new aspect in tumor induced immunology.

  17. Frequency of regulatory T cells determines the outcome of the T-cell-engaging antibody blinatumomab in patients with B-precursor ALL.

    Science.gov (United States)

    Duell, J; Dittrich, M; Bedke, T; Mueller, T; Eisele, F; Rosenwald, A; Rasche, L; Hartmann, E; Dandekar, T; Einsele, H; Topp, M S

    2017-10-01

    Blinatumomab can induce a complete haematological remission in patients in 46.6% with relapsed/refractory B-precursor acute lymphoblastic leukemia (r/r ALL) resulting in a survival benefit when compared with chemotherapy. Only bone marrow blast counts before therapy have shown a weak prediction of response. Here we investigated the role of regulatory T cells (Tregs), measured by CD4/CD25/FOXP3 expression, in predicting the outcome of immunotherapy with the CD19-directed bispecific T-cell engager construct blinatumomab. Blinatumomab responders (n=22) had an average of 4.82% Tregs (confidence interval (CI): 1.79-8.34%) in the peripheral blood, whereas non-responders (n=20) demonstrated 10.25% Tregs (CI: 3.36-65.9%). All other tested markers showed either no prediction value or an inferior prediction level including blast BM counts and the classical enzyme marker lactate dehydrogenase. With a cutoff of 8.525%, Treg enumeration can identify 100% of all blinatumomab responders and exclude 70% of the non-responders. The effect is facilitated by blinatumomab-activated Tregs, leading to interleukin-10 production, resulting in suppression of T-cell proliferation and reduced CD8-mediated lysis of ALL cells. Proliferation of patients' T cells can be restored by upfront removal of Tregs. Thus, enumeration of Treg identifies r/r ALL patients with a high response rate to blinatumomab. Therapeutic removal of Tregs may convert blinatumomab non-responders to responders.

  18. Glucocorticoids inhibit the proliferation of IL-2-dependent T cell clones

    International Nuclear Information System (INIS)

    Fresno, M.; Redondo, J.M.; Lopez-Rivas, A.

    1986-01-01

    It has been shown that glucocorticoids inhibit mitogen or antigen-induced lymphocyte proliferation by decreasing the production of interleukin-2 (IL-2). They have studied the effect of dexamethasone (Dx) on the proliferation of IL-2-dependent T cell clones. They have found that preincubation of these clones with Dx inhibits ( 3 H) thymidine incorporation and cell proliferation in a dose-dependent manner (ID 50 % 5 x 10 -10 M). The inhibition of DNA synthesis by Dx was dependent on the concentration of IL-2. High concentration of IL-2 reversed completely this inhibition. The action of Dx seems to be mediated through the induction of a protein since the simultaneous presence of cycloheximide and Dx prevented the inhibitory effect of the latter. Moreover, dialyzed conditioned medium of Dx treated cells inhibited DNA synthesis by T cell clones. The biochemical characterization of this protein is in progress

  19. Conditional IL-2 gene deletion: consequences for T cell proliferation

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    Kendall A Smith

    2012-05-01

    Full Text Available To explore the role of interleukin-2 (IL-2 in T cell proliferation, and to circumvent the IL-2 deficiency autoimmune syndrome of conventional il2 gene deletion, mice were created to allow conditional il2 gene deletion when treated with the estrogen analogue, tamoxifen (TAM as adults. Splenocytes from four different mouse strains, C57Bl/6 wild type (WT, conventional IL-2 (-/-, TAM-treated Cre recombinase negative (Cre-/IL2fl/fl, and Cre+/IL-2fl/fl (Cre+, were activated with anti-CD3 and anti-CD28, and monitored for CD4+ and CD8+ T cell lymphocyte blastogenesis, aerobic glycolysis, BrdU incorporation into newly synthesized DNA, and CFSE dye dilution to monitor cell division. IL-2 production was monitored by quantitative ELISA and multiple additional cytokines were monitored by protein-bead arrays. Splenocytes from conventional IL-2 (-/- and TAM-treated Cre+ mice resulted in undetectable IL-2 production, so that both strains were IL-2 deficient. As monitored by flow cytometry, activated CD4+ and CD8+ T cells from WT, Cre+ and Cre- mice all underwent blastogenesis, whereas far fewer cells from conventional IL-2 (-/- mice did so. By comparison, only cells from IL-2 sufficient WT and Cre- switched to aerobic glycolysis as evidenced by a drop in media pH. Blastogenesis was mirrored by BrdU incorporation and CFSE dye dilution by CD4+ and CD8+ T cells from WT, Cre+ and Cre- mice, which were all equivalent, while proliferation of cells from conventional IL-2 (-/- mice was compromised. Splenocytes from IL-2 deficient conventional IL-2 (-/- mice produced low or undetectable other γc-chain cytokines (IL-4, IL-7, IL-9, IL-13, IL-15, and IL-21, whereas production of these γc-chain cytokines from IL-2-deficient conditional IL-2 (-/- Cre+ mice were comparable with WT and Cre- mice. These results indicate that CD4+ and CD8+ T cell blastogenesis cannot be attributable to IL-2 alone, but a switch to aerobic glycolysis is attributable to IL-2, and proliferation

  20. Humanized CD7 nanobody-based immunotoxins exhibit promising anti-T-cell acute lymphoblastic leukemia potential

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    Yu Y

    2017-03-01

    all immunotoxins still maintained the ability to bind specifically to CD7-positive T lymphocyte strains without binding to CD7-negative control cells. Laser scanning confocal microscopy revealed that these proteins can be endocytosed into the cytoplasm after binding with CD7-positive cells and that this phenomenon was not observed in CD7-negative cells. WST-8 experiments showed that all immunotoxins retained the highly effective and specific growth inhibition activity in CD7-positive cell lines and primary T-cell acute lymphoblastic leukemia (T-ALL cells. Further in vivo animal model experiments showed that humanized dhuVHH6-PE38 immunotoxin can tolerate higher doses and extend the survival of NOD-Prkdcem26Il2rgem26Nju (NCG mice transplanted with CEM cells without any obvious decrease in body weight. Further studies on NCG mice model with patient-derived T-ALL cells, dhuVHH6-PE38 treatment, significantly prolonged mice survival with ~40% survival improvement. However, it was also noticed that although dhuVHH6-PE-LR showed strong antitumor effect in vitro, its in vivo antitumor efficacy was disappointing. Conclusion: We have successfully constructed a targeted CD7 molecule-modified nanobody (CD7 molecule-improved nanobody immunotoxin dhuVHH6-PE38 and demonstrated its potential for treating CD7-positive malignant tumors, especially T-cell acute lymphoblastic leukemia. Keywords: CD7, humanized nanobody, T-cell acute lymphoblastic leukemia, patient-derived xenograft model, recombinant immunotoxins, Pseudomonas exotoxin A

  1. Nonmalignant T cells stimulate growth of T-cell lymphoma cells in the presence of bacterial toxins

    DEFF Research Database (Denmark)

    Woetmann, Anders; Lovato, Paola; Eriksen, Karsten W

    2007-01-01

    Bacterial toxins including staphylococcal enterotoxins (SEs) have been implicated in the pathogenesis of cutaneous T-cell lymphomas (CTCLs). Here, we investigate SE-mediated interactions between nonmalignant T cells and malignant T-cell lines established from skin and blood of CTCL patients....... The malignant CTCL cells express MHC class II molecules that are high-affinity receptors for SE. Although treatment with SE has no direct effect on the growth of the malignant CTCL cells, the SE-treated CTCL cells induce vigorous proliferation of the SE-responsive nonmalignant T cells. In turn, the nonmalignant...... T cells enhance proliferation of the malignant cells in an SE- and MHC class II-dependent manner. Furthermore, SE and, in addition, alloantigen presentation by malignant CTCL cells to irradiated nonmalignant CD4(+) T-cell lines also enhance proliferation of the malignant cells. The growth...

  2. Novel T lymphocyte proliferation assessment using whole mouse cryo-imaging

    Science.gov (United States)

    Wuttisarnwattana, Patiwet; Raza, Syed A.; Eid, Saada; Cooke, Kenneth R.; Wilson, David L.

    2014-03-01

    New imaging technologies enable one to assess T-cell proliferation, an important feature of the immunological response. However, none of the traditional imaging modalities allow one to examine quantiatively T-cell function with microscopic resolution and single cell sensitivity over an entire mouse. To address this need, we established T-cells proliferation assays using 3D microscopic cryo-imaging. Assays include: (1) biodistribution of T-cells, (2) secondary lymphoid organ (SLO) volume measurement, (3) carboxyfluorescein succinimidyl ester (CFSE) dilution per cell as cells divide. To demonstrate the application, a graft-versus-host-disease (GVHD) model was used. 3D visualization show that T-cells specifically homed to the SLOs (spleen and lymph nodes) as well as GVHD target organs (such as GI-tract, liver, skin and thymus).The spleen was chosen as representative of the SLOs. For spleen size analysis, volumes of red and white pulp were measured. Spleen volumes of the allogeneic mice (with GVHD) were significantly larger than those of the syngeneic mice (without GVHD) at 72 to 120 hours post-transplant. For CFSE dilution approach, we employed color-coded volume rendering and probability density function (PDF) of single cell intensity to assess T-cell proliferation in the spleen. As compared to syngeneic T-cells, the allogeneic T-cells quickly aggregated in the spleen as indicated by increasing of CFSE signal over the first 48 hours. Then they rapidly proliferated as evidenced by reduced CFSE intensity (at 48-96 hours). Results suggest that assays can be used to study GVHD treatments using T-cell proliferation and biodistibution as assays. In summary, this is the first time that we are able to track and visualize T-cells in whole mouse with single cell sensitivity. We believe that our technique can be an alternative choice to traditional in vitro immunological proliferation assays by providing assessment of proliferation in an in vivo model.

  3. Proliferating cells in psoriatic dermis are comprised primarily of T cells, endothelial cells, and factor XIIIa+ perivascular dendritic cells

    International Nuclear Information System (INIS)

    Morganroth, G.S.; Chan, L.S.; Weinstein, G.D.; Voorhees, J.J.; Cooper, K.D.

    1991-01-01

    Determination of the cell types proliferating in the dermis of patients with psoriasis should identify those cells experiencing activation or responding to growth factors in the psoriatic dermal milieu. Toward that end, sections of formalin-fixed biopsies obtained from 3H-deoxyuridine (3H-dU)-injected skin of eight psoriatic patients were immunostained, followed by autoradiography. Proliferating dermal cells exhibit silver grains from tritium emissions. The identity of the proliferating cells could then be determined by simultaneous visualization with antibodies specific for various cell types. UCHL1+ (CD45RO+) T cells (recall antigen-reactive helper T-cell subset) constituted 36.6 +/- 3.1% (mean +/- SEM, n = 6) of the proliferating dermal cells in involved skin, whereas Leu 18+ (CD45RA+) T cells (recall antigen naive T-cell subsets) comprised only 8.7 +/- 1.5% (n = 6). The Factor XIIIa+ dermal perivascular dendritic cell subset (24.9 +/- 1.5% of proliferating dermal cells, n = 6) and Factor VIII+ endothelial cells represented the two other major proliferating populations in lesional psoriatic dermis. Differentiated tissue macrophages, identified by phase microscopy as melanophages or by immunostaining with antibodies to Leu M1 (CD15) or myeloid histiocyte antigen, comprised less than 5% of the proliferating population in either skin type. In addition to calculating the relative proportions of these cells to each other as percent, we also determined the density of cells, in cells/mm2 of tissue. The density of proliferating cells within these populations was increased in involved versus uninvolved skin: UCHL1+, 9.0 +/- 1.7 cells/mm2 versus 1.8 +/- 0.6 cells/mm2, p less than 0.01; Factor XIIIa+, 6.0 +/- 0.7 cells/mm2 versus 1.5 +/- 0.5 cells/mm2, p less than 0.01; Factor VIII+, 5.5 +/- 1.4 cells/mm2 versus 0.0 cells/mm2, p less than 0.05

  4. Immortalization of T-Cells Is Accompanied by Gradual Changes in CpG Methylation Resulting in a Profile Resembling a Subset of T-Cell Leukemias

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    Sofie Degerman

    2014-07-01

    Full Text Available We have previously described gene expression changes during spontaneous immortalization of T-cells, thereby identifying cellular processes important for cell growth crisis escape and unlimited proliferation. Here, we analyze the same model to investigate the role of genome-wide methylation in the immortalization process at different time points pre-crisis and post-crisis using high-resolution arrays. We show that over time in culture there is an overall accumulation of methylation alterations, with preferential increased methylation close to transcription start sites (TSSs, islands, and shore regions. Methylation and gene expression alterations did not correlate for the majority of genes, but for the fraction that correlated, gain of methylation close to TSS was associated with decreased gene expression. Interestingly, the pattern of CpG site methylation observed in immortal T-cell cultures was similar to clinical T-cell acute lymphoblastic leukemia (T-ALL samples classified as CpG island methylator phenotype positive. These sites were highly overrepresented by polycomb target genes and involved in developmental, cell adhesion, and cell signaling processes. The presence of non-random methylation events in in vitro immortalized T-cell cultures and diagnostic T-ALL samples indicates altered methylation of CpG sites with a possible role in malignant hematopoiesis.

  5. The common oncogenomic program of NOTCH1 and NOTCH3 signaling in T-cell acute lymphoblastic leukemia.

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    Sung Hee Choi

    Full Text Available Notch is a major oncogenic driver in T cell acute lymphoblastic leukemia (T-ALL, in part because it binds to an enhancer that increases expression of MYC. Here, we exploit the capacity of activated NOTCH1 and NOTCH3 to induce T-ALL, despite substantial divergence in their intracellular regions, as a means to elucidate a broad, common Notch-dependent oncogenomic program through systematic comparison of the transcriptomes and Notch-bound genomic regulatory elements of NOTCH1- and NOTCH3-dependent T-ALL cells. ChIP-seq studies show a high concordance of functional NOTCH1 and NOTCH3 genomic binding sites that are enriched in binding motifs for RBPJ, the transcription factor that recruits activated Notch to DNA. The interchangeability of NOTCH1 and NOTCH3 was confirmed by rescue of NOTCH1-dependent T-ALL cells with activated NOTCH3 and vice versa. Despite remarkable overall similarity, there are nuanced differences in chromatin landscapes near critical common Notch target genes, most notably at a Notch-dependent enhancer that regulates MYC, which correlates with responsiveness to Notch pathway inhibitors. Overall, a common oncogenomic program driven by binding of either Notch is sufficient to maintain T-ALL cell growth, whereas cell-context specific differences appear to influence the response of T-ALL cells to Notch inhibition.

  6. Aberrant TAL1 activation is mediated by an interchromosomal interaction in human T-cell acute lymphoblastic leukemia.

    Science.gov (United States)

    Patel, B; Kang, Y; Cui, K; Litt, M; Riberio, M S J; Deng, C; Salz, T; Casada, S; Fu, X; Qiu, Y; Zhao, K; Huang, S

    2014-02-01

    Long-range chromatin interactions control metazoan gene transcription. However, the involvement of intra- and interchromosomal interactions in development and oncogenesis remains unclear. TAL1/SCL is a critical transcription factor required for the development of all hematopoietic lineages; yet, aberrant TAL1 transcription often occurs in T-cell acute lymphoblastic leukemia (T-ALL). Here, we report that oncogenic TAL1 expression is regulated by different intra- and interchromosomal loops in normal hematopoietic and leukemic cells, respectively. These intra- and interchromosomal loops alter the cell-type-specific enhancers that interact with the TAL1 promoter. We show that human SET1 (hSET1)-mediated H3K4 methylations promote a long-range chromatin loop, which brings the +51 enhancer in close proximity to TAL1 promoter 1 in erythroid cells. The CCCTC-binding factor (CTCF) facilitates this long-range enhancer/promoter interaction of the TAL1 locus in erythroid cells while blocking the same enhancer/promoter interaction of the TAL1 locus in human T-cell leukemia. In human T-ALL, a T-cell-specific transcription factor c-Maf-mediated interchromosomal interaction brings the TAL1 promoter into close proximity with a T-cell-specific regulatory element located on chromosome 16, activating aberrant TAL1 oncogene expression. Thus, our study reveals a novel molecular mechanism involving changes in three-dimensional chromatin interactions that activate the TAL1 oncogene in human T-cell leukemia.

  7. Distribution of adoptively transferred porcine T-lymphoblasts tracked by {sup 18}F-2-fluoro-2-deoxy-D-glucose and position emission tomography

    Energy Technology Data Exchange (ETDEWEB)

    Eriksson, Olof, E-mail: olof.eriksson@radiol.uu.se [Division of Radiology, Department of Oncology, Radiology, Oncology and Radiation Science, Uppsala University, Uppsala 751 87 (Sweden); Uppsala Imanet AB, GE Healthcare, Uppsala 751 85 (Sweden); Sadeghi, Arian; Carlsson, Bjoern; Eich, Torsten [Division of Immunology, Department of Immunology, Genetics and Pathology, Uppsala University, Uppsala 751 87 (Sweden); Lundgren, Torbjoern [Division of Transplantation Surgery, CLINTEC, Karolinska Institute, Stockholm 171 77 (Sweden); Nilsson, Bo; Toetterman, Thomas; Korsgren, Olle [Division of Immunology, Department of Immunology, Genetics and Pathology, Uppsala University, Uppsala 751 87 (Sweden); Sundin, Anders [Division of Radiology, Department of Oncology, Radiology, Oncology and Radiation Science, Uppsala University, Uppsala 751 87 (Sweden); Department of Radiology, Karolinska University Hospital and Molecular Medicine and Surgery, Karolinska Institute, Stockholm 171 77 (Sweden)

    2011-08-15

    Introduction: Autologous or allogeneic transfer of tumor-infiltrating T-lymphocytes is a promising treatment for metastatic cancers, but a major concern is the difficulty in evaluating cell trafficking and distribution in adoptive cell therapy. This study presents a method of tracking transfusion of T-lymphoblasts in a porcine model by {sup 18}F-2-fluoro-2-deoxy-D-glucose ([{sup 18}F]FDG) and positron emission tomography. Methods: T-lymphoblasts were labeled with the positron-emitting tracer [{sup 18}F]FDG through incubation. The T-lymphoblasts were administered into the bloodstream, and the distribution was followed by positron emission tomography for 120 min. The cells were administered either intravenously into the internal jugular vein (n=5) or intraarterially into the ascending aorta (n=1). Two of the pigs given intravenous administration were pretreated with low-molecular-weight dextran sulphate. Results: The cellular kinetics and distribution were readily quantifiable for up to 120 min. High (78.6% of the administered cells) heterogeneous pulmonary uptake was found after completed intravenous transfusion. The pulmonary uptake was decreased either by preincubating and coadministrating the T-lymphoblasts with low-molecular-weight dextran sulphate or by administrating them intraarterially. Conclusions: The present work shows the feasibility of quantitatively monitoring and evaluating cell trafficking and distribution following administration of [{sup 18}F]FDG-labeled T-lymphoblasts. The protocol can potentially be transferred to the clinical setting with few modifications.

  8. The brain microvascular endothelium supports T cell proliferation and has potential for alloantigen presentation.

    Directory of Open Access Journals (Sweden)

    Julie Wheway

    Full Text Available Endothelial cells (EC form the inner lining of blood vessels and are positioned between circulating lymphocytes and tissues. Hypotheses have formed that EC may act as antigen presenting cells based on the intimate interactions with T cells, which are seen in diseases like multiple sclerosis, cerebral malaria (CM and viral neuropathologies. Here, we investigated how human brain microvascular EC (HBEC interact with and support the proliferation of T cells. We found HBEC to express MHC II, CD40 and ICOSL, key molecules for antigen presentation and co-stimulation and to take up fluorescently labeled antigens via macropinocytosis. In co-cultures, we showed that HBEC support and promote the proliferation of CD4(+ and CD8(+ T cells, which both are key in CM pathogenesis, particularly following T cell receptor activation and co-stimulation. Our findings provide novel evidence that HBEC can trigger T cell activation, thereby providing a novel mechanism for neuroimmunological complications of infectious diseases.

  9. Humanized CD7 nanobody-based immunotoxins exhibit promising anti-T-cell acute lymphoblastic leukemia potential.

    Science.gov (United States)

    Yu, Yuan; Li, Jialu; Zhu, Xuejun; Tang, Xiaowen; Bao, Yangyi; Sun, Xiang; Huang, Yuhui; Tian, Fang; Liu, Xiaomei; Yang, Lin

    2017-01-01

    Nanobodies, named as VHHs (variable domain of heavy chain of HCAb [heavy-chain antibodies]), are derived from heavy-chain-only antibodies that circulate in sera of camelids. Their exceptional physicochemical properties, possibility of humanization, and unique antigen recognition properties make them excellent candidates for targeted delivery of biologically active components, including immunotoxins. In our previous efforts, we have successfully generated the monovalent and bivalent CD7 nanobody-based immunotoxins, which can effectively trigger the apoptosis of CD7-positive malignant cells. To pursue the possibility of translating those immunotoxins into clinics, we humanized the nanobody sequences (designated as dhuVHH6) as well as further truncated the Pseudomonas exotoxin A (PE)-derived PE38 toxin to produce a more protease-resistant form, which is named as PE-LR, by deleting majority of PE domain II. Three new types of immunotoxins, dhuVHH6-PE38, dVHH6-PE-LR, and dhuVHH6-PE-LR, were successfully constructed. These recombinant immunotoxins were expressed in Escherichia coli and showed that nanobody immunotoxins have the benefits of easy soluble expression in a prokaryotic expression system. Flow cytometry results revealed that all immunotoxins still maintained the ability to bind specifically to CD7-positive T lymphocyte strains without binding to CD7-negative control cells. Laser scanning confocal microscopy revealed that these proteins can be endocytosed into the cytoplasm after binding with CD7-positive cells and that this phenomenon was not observed in CD7-negative cells. WST-8 experiments showed that all immunotoxins retained the highly effective and specific growth inhibition activity in CD7-positive cell lines and primary T-cell acute lymphoblastic leukemia (T-ALL) cells. Further in vivo animal model experiments showed that humanized dhuVHH6-PE38 immunotoxin can tolerate higher doses and extend the survival of NOD-Prkdc em26 Il2rg em26 Nju (NCG) mice

  10. Childhood pre-B cell acute lymphoblastic leukemia with translocation t(1;19)(q21.1;p13.3) and two additional chromosomal aberrations involving chromosomes 1, 6, and 13: a case report.

    Science.gov (United States)

    Wafa, Abdulsamad; As'sad, Manar; Liehr, Thomas; Aljapawe, Abdulmunim; Al Achkar, Walid

    2017-04-07

    The translocation t(1;19)(q23;p13), which results in the TCF3-PBX1 chimeric gene, is one of the most frequent rearrangements observed in B cell acute lymphoblastic leukemia. It appears in both adult and pediatric patients with B cell acute lymphoblastic leukemia at an overall frequency of 3 to 5%. Most cases of pre-B cell acute lymphoblastic leukemia carrying the translocation t(1;19) have a typical immunophenotype with homogeneous expression of CD19, CD10, CD9, complete absence of CD34, and at least diminished CD20. Moreover, the translocation t(1;19) correlates with known clinical high risk factors, such as elevated white blood cell count, high serum lactate dehydrogenase levels, and central nervous system involvement; early reports indicated that patients with translocation t(1;19) had a poor outcome under standard treatment. We report the case of a 15-year-old Syrian boy with pre-B cell acute lymphoblastic leukemia with abnormal karyotype with a der(19)t(1;19)(q21.1;p13.3) and two yet unreported chromosomal aberrations: an interstitial deletion 6q12 to 6q26 and a der(13)t(1;13)(q21.1;p13). According to the literature, cases who are translocation t(1;19)-positive have a significantly higher incidence of central nervous system relapse than patients with acute lymphoblastic leukemia without the translocation. Of interest, central nervous system involvement was also seen in our patient. To the best of our knowledge, this is the first case of childhood pre-B cell acute lymphoblastic leukemia with an unbalanced translocation t(1;19) with two additional chromosomal aberrations, del(6)(q12q26) and t(1;13)(q21.3;p13), which seem to be recurrent and could influence clinical outcome. Also the present case confirms the impact of the translocation t(1;19) on central nervous system relapse, which should be studied for underlying mechanisms in future.

  11. Cooperation of IRAK1/4 inhibitor and ABT-737 in nanoparticles for synergistic therapy of T cell acute lymphoblastic leukemia

    Directory of Open Access Journals (Sweden)

    Wu X

    2017-10-01

    Full Text Available Xiaoyan Wu,1 Lin Wang,1 Yining Qiu,1 Bingyu Zhang,1 Zhenhua Hu,2 Runming Jin1 1Department of Pediatrics, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, 2Department of Pharmacy, Shanghai Jiao Tong University, Shanghai, China Abstract: T cell acute lymphoblastic leukemia (T-ALL is caused by clonal expansion of variant T cell progenitors and is considered as a high risk leukemia. Contemporary single chemotherapy has a limited effect due to dynamic and versatile properties of T-ALL. Here IRAK1/4 inhibitor and ABT-737 were co-encapsulated into polyethylene glycol modified poly (lactic-co-glycolic acid nanoparticles (IRAK/ABT-NP to enhance synergistic therapy of T-ALL. The formulation was optimized to achieve high drug loading using Box-Behnken design and response surface methodology. The optimal parameter comprised 2.98% polymer in acetonitrile, a ratio of oil phase to water phase of 1:8.33, and 2.12% emulsifier concentration. High drug loading and uniform spherical shape was achieved. In vitro release study showed sustained release of IRAK1/4 inhibitor for 72 hours as well as sustained release of ABT-737 for more than 120 hours. Uptake efficiency of IRAK/ABT-NP and induced apoptotic T-ALL fraction by IRAK/ABT-NP were much higher than the IRAK1/4 and ABT-737 combined solution. IC50 of IRAK/ABT-NP was two-fold lower than free drug combination in Jurkat cells. Additionally, we conducted in vivo experiments in which IRAK/ABT-NP exhibited greater cytotoxicity toward T-ALL cells, the capacity to significantly restore white blood cell number in peripheral blood, and improved survival time of T-ALL mouse model compared to the IRAK1/4 and ABT-737 combined solution. Keywords: T cell acute lymphoblastic leukemia, IRAK1/4 inhibitor, ABT-737, Box-Behnken design and response surface methodology, PEG-PLGA

  12. Progranulin Inhibits Human T Lymphocyte Proliferation by Inducing the Formation of Regulatory T Lymphocytes

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    Kyu Hwan Kwack

    2017-01-01

    Full Text Available We have examined the effect of progranulin (PGRN on human T cell proliferation and its underlying mechanism. We show that PGRN inhibits the PHA-induced multiplication of T lymphocytes. It increases the number of iTregs when T lymphocytes are activated by PHA but does not do so in the absence of PHA. PGRN-mediated inhibition of T lymphocyte proliferation, as well as the induction of iTregs, was completely reversed by a TGF-β inhibitor or a Treg inhibitor. PGRN induced TGF-β secretion in the presence of PHA whereas it did not in the absence of PHA. Our findings indicate that PGRN suppresses T lymphocyte proliferation by enhancing the formation of iTregs from activated T lymphocytes in response to TGF-β.

  13. Identification of chimeric antigen receptors that mediate constitutive or inducible proliferation of T cells.

    Science.gov (United States)

    Frigault, Matthew J; Lee, Jihyun; Basil, Maria Ciocca; Carpenito, Carmine; Motohashi, Shinichiro; Scholler, John; Kawalekar, Omkar U; Guedan, Sonia; McGettigan, Shannon E; Posey, Avery D; Ang, Sonny; Cooper, Laurence J N; Platt, Jesse M; Johnson, F Brad; Paulos, Chrystal M; Zhao, Yangbing; Kalos, Michael; Milone, Michael C; June, Carl H

    2015-04-01

    This study compared second-generation chimeric antigen receptors (CAR) encoding signaling domains composed of CD28, ICOS, and 4-1BB (TNFRSF9). Here, we report that certain CARs endow T cells with the ability to undergo long-term autonomous proliferation. Transduction of primary human T cells with lentiviral vectors encoding some of the CARs resulted in sustained proliferation for up to 3 months following a single stimulation through the T-cell receptor (TCR). Sustained numeric expansion was independent of cognate antigen and did not require the addition of exogenous cytokines or feeder cells after a single stimulation of the TCR and CD28. Results from gene array and functional assays linked sustained cytokine secretion and expression of T-bet (TBX21), EOMES, and GATA-3 to the effect. Sustained expression of the endogenous IL2 locus has not been reported in primary T cells. Sustained proliferation was dependent on CAR structure and high expression, the latter of which was necessary but not sufficient. The mechanism involves constitutive signaling through NF-κB, AKT, ERK, and NFAT. The propagated CAR T cells retained a diverse TCR repertoire, and cellular transformation was not observed. The CARs with a constitutive growth phenotype displayed inferior antitumor effects and engraftment in vivo. Therefore, the design of CARs that have a nonconstitutive growth phenotype may be a strategy to improve efficacy and engraftment of CAR T cells. The identification of CARs that confer constitutive or nonconstitutive growth patterns may explain observations that CAR T cells have differential survival patterns in clinical trials. ©2015 American Association for Cancer Research.

  14. Resveratrol given intraperitoneally does not inhibit growth of high-risk t(4;11) acute lymphoblastic leukemia cells in NOD/SCID mouse model

    Science.gov (United States)

    The efficacy of the phytochemical resveratrol as a preventive agent against the growth of t(4;11) acute lymphoblastic leukemia (ALL) was evaluated in NOD.CB17-Prkdcscid/J mice engrafted with the human t(4;11) ALL line SEM. SEM cells were injected into the tail vein and engraftment was monitored by ...

  15. Homeostatic proliferation fails to efficiently reactivate HIV-1 latently infected central memory CD4+ T cells.

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    Alberto Bosque

    2011-10-01

    Full Text Available Homeostatic proliferation ensures the longevity of central memory T-cells by inducing cell proliferation in the absence of cellular differentiation or activation. This process is governed mainly by IL-7. Central memory T-cells can also be stimulated via engagement of the T-cell receptor, leading to cell proliferation but also activation and differentiation. Using an in vitro model of HIV-1 latency, we have examined in detail the effects of homeostatic proliferation on latently infected central memory T cells. We have also used antigenic stimulation via anti-CD3/anti-CD28 antibodies and established a comparison with a homeostatic proliferation stimulus, to evaluate potential differences in how either treatment affects the dynamics of latent virus populations. First, we show that homeostatic proliferation, as induced by a combination of IL-2 plus IL-7, leads to partial reactivation of latent HIV-1 but is unable to reduce the size of the reservoir in vitro. Second, latently infected cells are able to homeostatically proliferate in the absence of viral reactivation or cell differentiation. These results indicate that IL-2 plus IL-7 may induce a detrimental effect by favoring the maintenance of the latent HIV-1 reservoir. On the other hand, antigenic stimulation efficiently reactivated latent HIV-1 in cultured central memory cells and led to depletion of the latently infected cells via virus-induced cell death.

  16. Antigen-specific and non-specific CD4+ T cell recruitment and proliferation during influenza infection

    International Nuclear Information System (INIS)

    Chapman, Timothy J.; Castrucci, Maria R.; Padrick, Ryan C.; Bradley, Linda M.; Topham, David J.

    2005-01-01

    To track epitope-specific CD4 + T cells at a single-cell level during influenza infection, the MHC class II-restricted OVA 323-339 epitope was engineered into the neuraminidase stalk of influenza/A/WSN, creating a surrogate viral antigen. The recombinant virus, influenza A/WSN/OVA II , replicated well, was cleared normally, and stimulated both wild-type and DO11.10 or OT-II TCR transgenic OVA-specific CD4 + T cells. OVA-specific CD4 T cells proliferated during infection only when the OVA epitope was present. However, previously primed (but not naive) transgenic CD4 + T cells were recruited to the infected lung both in the presence and absence of the OVA 323-339 epitope. These data show that, when primed, CD4 + T cells may traffic to the lung in the absence of antigen, but do not proliferate. These results also document a useful tool for the study of CD4 T cells in influenza infection

  17. FOXO3 regulates CD8 T cell memory by T cell-intrinsic mechanisms.

    Directory of Open Access Journals (Sweden)

    Jeremy A Sullivan

    2012-02-01

    Full Text Available CD8 T cell responses have three phases: expansion, contraction, and memory. Dynamic alterations in proliferation and apoptotic rates control CD8 T cell numbers at each phase, which in turn dictate the magnitude of CD8 T cell memory. Identification of signaling pathways that control CD8 T cell memory is incomplete. The PI3K/Akt signaling pathway controls cell growth in many cell types by modulating the activity of FOXO transcription factors. But the role of FOXOs in regulating CD8 T cell memory remains unknown. We show that phosphorylation of Akt, FOXO and mTOR in CD8 T cells occurs in a dynamic fashion in vivo during an acute viral infection. To elucidate the potentially dynamic role for FOXO3 in regulating homeostasis of activated CD8 T cells in lymphoid and non-lymphoid organs, we infected global and T cell-specific FOXO3-deficient mice with Lymphocytic Choriomeningitis Virus (LCMV. We found that FOXO3 deficiency induced a marked increase in the expansion of effector CD8 T cells, preferentially in the spleen, by T cell-intrinsic mechanisms. Mechanistically, the enhanced accumulation of proliferating CD8 T cells in FOXO3-deficient mice was not attributed to an augmented rate of cell division, but instead was linked to a reduction in cellular apoptosis. These data suggested that FOXO3 might inhibit accumulation of growth factor-deprived proliferating CD8 T cells by reducing their viability. By virtue of greater accumulation of memory precursor effector cells during expansion, the numbers of memory CD8 T cells were strikingly increased in the spleens of both global and T cell-specific FOXO3-deficient mice. The augmented CD8 T cell memory was durable, and FOXO3 deficiency did not perturb any of the qualitative attributes of memory T cells. In summary, we have identified FOXO3 as a critical regulator of CD8 T cell memory, and therapeutic modulation of FOXO3 might enhance vaccine-induced protective immunity against intracellular pathogens.

  18. MicroRNA-193b-3p acts as a tumor suppressor by targeting the MYB oncogene in T-cell acute lymphoblastic leukemia

    OpenAIRE

    Mets, E; Van der Meulen, J; Van Peer, G; Boice, M; Mestdagh, P; Van de Walle, I; Lammens, T; Goossens, S; De Moerloose, B; Benoit, Y; Van Roy, N; Clappier, E; Poppe, B; Vandesompele, J; Wendel, H-G

    2014-01-01

    The MYB oncogene is a leucine zipper transcription factor essential for normal and malignant hematopoiesis. In T-cell acute lymphoblastic leukemia (T-ALL), elevated MYB levels can arise directly through T-cell receptor-mediated MYB translocations, genomic MYB duplications or enhanced TAL1 complex binding at the MYB locus or indirectly through the TAL1/miR-223/FBXW7 regulatory axis. In this study, we used an unbiased MYB 3′untranslated region–microRNA (miRNA) library screen and identified 33 p...

  19. Immortalization of T-cells is accompanied by gradual changes in CpG methylation resulting in a profile resembling a subset of T-cell leukemias.

    Science.gov (United States)

    Degerman, Sofie; Landfors, Mattias; Siwicki, Jan Konrad; Revie, John; Borssén, Magnus; Evelönn, Emma; Forestier, Erik; Chrzanowska, Krystyna H; Rydén, Patrik; Keith, W Nicol; Roos, Göran

    2014-07-01

    We have previously described gene expression changes during spontaneous immortalization of T-cells, thereby identifying cellular processes important for cell growth crisis escape and unlimited proliferation. Here, we analyze the same model to investigate the role of genome-wide methylation in the immortalization process at different time points pre-crisis and post-crisis using high-resolution arrays. We show that over time in culture there is an overall accumulation of methylation alterations, with preferential increased methylation close to transcription start sites (TSSs), islands, and shore regions. Methylation and gene expression alterations did not correlate for the majority of genes, but for the fraction that correlated, gain of methylation close to TSS was associated with decreased gene expression. Interestingly, the pattern of CpG site methylation observed in immortal T-cell cultures was similar to clinical T-cell acute lymphoblastic leukemia (T-ALL) samples classified as CpG island methylator phenotype positive. These sites were highly overrepresented by polycomb target genes and involved in developmental, cell adhesion, and cell signaling processes. The presence of non-random methylation events in in vitro immortalized T-cell cultures and diagnostic T-ALL samples indicates altered methylation of CpG sites with a possible role in malignant hematopoiesis. Copyright © 2014 Neoplasia Press, Inc. Published by Elsevier Inc. All rights reserved.

  20. Chimeric-antigen receptor T (CAR-T) cell therapy for solid tumors: challenges and opportunities.

    Science.gov (United States)

    Xia, An-Liang; Wang, Xiao-Chen; Lu, Yi-Jun; Lu, Xiao-Jie; Sun, Beicheng

    2017-10-27

    Chimeric antigen receptor (CAR)-engineered T cells (CAR-T cells) have been shown to have unprecedented efficacy in B cell malignancies, most notably in B cell acute lymphoblastic leukemia (B-ALL) with up to a 90% complete remission rate using anti-CD19 CAR-T cells. However, CAR T-cell therapy for solid tumors currently is faced with numerous challenges such as physical barriers, the immunosuppressive tumor microenvironment and the specificity and safety. The clinical results in solid tumors have been much less encouraging, with multiple cases of toxicity and a lack of therapeutic response. In this review, we will discuss the current stats and challenges of CAR-T cell therapy for solid tumors, and propose possibl e solutions and future perspectives.

  1. The depletion of nuclear glutathione impairs cell proliferation in 3t3 fibroblasts.

    Directory of Open Access Journals (Sweden)

    Jelena Markovic

    2009-07-01

    Full Text Available Glutathione is considered essential for survival in mammalian cells and yeast but not in prokaryotic cells. The presence of a nuclear pool of glutathione has been demonstrated but its role in cellular proliferation and differentiation is still a matter of debate.We have studied proliferation of 3T3 fibroblasts for a period of 5 days. Cells were treated with two well known depleting agents, diethyl maleate (DEM and buthionine sulfoximine (BSO, and the cellular and nuclear glutathione levels were assessed by analytical and confocal microscopic techniques, respectively. Both agents decreased total cellular glutathione although depletion by BSO was more sustained. However, the nuclear glutathione pool resisted depletion by BSO but not with DEM. Interestingly, cell proliferation was impaired by DEM, but not by BSO. Treating the cells simultaneously with DEM and with glutathione ethyl ester to restore intracellular GSH levels completely prevented the effects of DEM on cell proliferation.Our results demonstrate the importance of nuclear glutathione in the control of cell proliferation in 3T3 fibroblasts and suggest that a reduced nuclear environment is necessary for cells to progress in the cell cycle.

  2. MicroRNA-193b-3p acts as a tumor suppressor by targeting the MYB oncogene in T-cell acute lymphoblastic leukemia.

    Science.gov (United States)

    Mets, E; Van der Meulen, J; Van Peer, G; Boice, M; Mestdagh, P; Van de Walle, I; Lammens, T; Goossens, S; De Moerloose, B; Benoit, Y; Van Roy, N; Clappier, E; Poppe, B; Vandesompele, J; Wendel, H-G; Taghon, T; Rondou, P; Soulier, J; Van Vlierberghe, P; Speleman, F

    2015-04-01

    The MYB oncogene is a leucine zipper transcription factor essential for normal and malignant hematopoiesis. In T-cell acute lymphoblastic leukemia (T-ALL), elevated MYB levels can arise directly through T-cell receptor-mediated MYB translocations, genomic MYB duplications or enhanced TAL1 complex binding at the MYB locus or indirectly through the TAL1/miR-223/FBXW7 regulatory axis. In this study, we used an unbiased MYB 3'untranslated region-microRNA (miRNA) library screen and identified 33 putative MYB-targeting miRNAs. Subsequently, transcriptome data from two independent T-ALL cohorts and different subsets of normal T-cells were used to select miRNAs with relevance in the context of normal and malignant T-cell transformation. Hereby, miR-193b-3p was identified as a novel bona fide tumor-suppressor miRNA that targets MYB during malignant T-cell transformation thereby offering an entry point for efficient MYB targeting-oriented therapies for human T-ALL.

  3. Core transcriptional regulatory circuit controlled by the TAL1 complex in human T cell acute lymphoblastic leukemia.

    Science.gov (United States)

    Sanda, Takaomi; Lawton, Lee N; Barrasa, M Inmaculada; Fan, Zi Peng; Kohlhammer, Holger; Gutierrez, Alejandro; Ma, Wenxue; Tatarek, Jessica; Ahn, Yebin; Kelliher, Michelle A; Jamieson, Catriona H M; Staudt, Louis M; Young, Richard A; Look, A Thomas

    2012-08-14

    The oncogenic transcription factor TAL1/SCL is aberrantly expressed in over 40% of cases of human T cell acute lymphoblastic leukemia (T-ALL), emphasizing its importance in the molecular pathogenesis of T-ALL. Here we identify the core transcriptional regulatory circuit controlled by TAL1 and its regulatory partners HEB, E2A, LMO1/2, GATA3, and RUNX1. We show that TAL1 forms a positive interconnected autoregulatory loop with GATA3 and RUNX1 and that the TAL1 complex directly activates the MYB oncogene, forming a positive feed-forward regulatory loop that reinforces and stabilizes the TAL1-regulated oncogenic program. One of the critical downstream targets in this circuitry is the TRIB2 gene, which is oppositely regulated by TAL1 and E2A/HEB and is essential for the survival of T-ALL cells. Copyright © 2012 Elsevier Inc. All rights reserved.

  4. CD4+ FOXP3+ Regulatory T Cells Exhibit Impaired Ability to Suppress Effector T Cell Proliferation in Patients with Turner Syndrome.

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    Young Ah Lee

    Full Text Available We investigated whether the frequency, phenotype, and suppressive function of CD4+ FOXP3+ regulatory T cells (Tregs are altered in young TS patients with the 45,X karyotype compared to age-matched controls.Peripheral blood mononuclear cells from young TS patients (n = 24, 17.4-35.9 years and healthy controls (n = 16 were stained with various Treg markers to characterize their phenotypes. Based on the presence of thyroid autoimmunity, patients were categorized into TS (- (n = 7 and TS (+ (n = 17. Tregs sorted for CD4+ CD25bright were co-cultured with autologous CD4+ CD25- target cells in the presence of anti-CD3 and -CD28 antibodies to assess their suppressive function.Despite a lower frequency of CD4+ T cells in the TS (- and TS (+ patients (mean 30.8% and 31.7%, vs. 41.2%; P = 0.003 and P < 0.001, respectively, both groups exhibited a higher frequency of FOXP3+ Tregs among CD4+ T cells compared with controls (means 1.99% and 2.05%, vs. 1.33%; P = 0.029 and P = 0.004, respectively. There were no differences in the expression of CTLA-4 and the frequency of Tregs expressing CXCR3+, and CCR4+ CCR6+ among the three groups. However, the ability of Tregs to suppress the in vitro proliferation of autologous CD4+ CD25- T cells was significantly impaired in the TS (- and TS (+ patients compared to controls (P = 0.003 and P = 0.041. Meanwhile, both the TS (- and TS (+ groups had lower frequencies of naïve cells (P = 0.001 for both but higher frequencies of effector memory cells (P = 0.004 and P = 0.002 than did the healthy control group.The Tregs of the TS patients could not efficiently suppress the proliferation of autologous effector T cells, despite their increased frequency in peripheral CD4+ T cells.

  5. Reduction of myeloid suppressor cell derived nitric oxide provides a mechanistic basis of lead enhancement of alloreactive CD4+ T cell proliferation

    International Nuclear Information System (INIS)

    Farrer, David G.; Hueber, Sara; Laiosa, Michael D.; Eckles, Kevin G.; McCabe, Michael J.

    2008-01-01

    The persistent environmental toxicant and immunomodulator, lead (Pb), has been proposed to directly target CD4 + T cells. However, our studies suggest that CD4 + T cells are an important functional, yet indirect target. In order to identify the direct target of Pb in the immune system and the potential mechanism of Pb-induced immunotoxicity, myeloid suppressor cells (MSCs) were evaluated for their ability to modulate CD4 + T cell proliferation after Pb exposure. Myeloid suppressor cells regulate the adaptive immune response, in part, by inhibiting the proliferation of CD4 + T cells. It is thought that the mechanism of MSC-dependent regulation involves the release of the bioactive gas, nitric oxide (NO), blocking cell signaling cascades downstream of the IL-2 receptor and thus preventing T cells from entering cell-cycle. In mixed lymphocyte culture (MLC), increasing numbers of MSCs suppressed T cell proliferation in a dose-dependent manner, and this suppression is strikingly abrogated with 5 μM lead (Pb) treatment. The Pb-sensitive MSC population is CD11b + , GR1 + and CD11c - and thus phenotypically consistent with MSCs described in other literature. Inhibition of NO-synthase (NOS), the enzyme responsible for the production of NO, enhanced alloreactive T cell proliferation in MLC. Moreover, Pb attenuated NO production in MLC, and exogenous replacement of NO restored suppression in the presence of Pb. Significantly, MSC from iNOS-/- mice were unable to suppress T cell proliferation. An MSC-derived cell line (MSC-1) also suppressed T cell proliferation in MLC, and Pb disrupted this suppression by attenuating NO production. Additionally, Pb disrupted NO production in MSC-1 cells in response to treatment with interferon-γ (IFN-γ) and LPS or in response to concanavalin A-stimulated splenocytes. However, neither the abundance of protein nor levels of mRNA for the inducible isoform of NOS (iNOS) were altered with Pb treatment. Taken together these data suggest that Pb

  6. Interleukin-7 receptor-α gene mutations are not detected in adult T-cell acute lymphoblastic leukemia

    International Nuclear Information System (INIS)

    Rozovski, Uri; Li, Ping; Harris, David; Ohanian, Maro; Kantarjian, Hagop; Estrov, Zeev

    2014-01-01

    Somatic mutations in cancer cell genes are classified according to their functional significance. Those that provide the malignant cells with significant advantage are collectively referred to as driver mutations and those that do not, are the passenger mutations. Accordingly, analytical criteria to distinguish driver mutations from passenger mutations have been recently suggested. Recent studies revealed mutations in interleukin-7 receptor-α (IL7R) gene in 10% of pediatric T-cell acute lymphoblastic leukemia (T-ALL) patients and in only a few cases of pediatric B-ALL. IL7R mutations are also frequently found in patients with lung cancer, but whereas in pediatric T-ALL IL7R mutations are “drivers” (consisting of gain-of-function mutations within a narrow 50-base pair interval at exon 6 that confer cytokine-independent cell growth and promote tumor transformation), in lung cancer, mutations are substitution mutations randomly distributed across the gene and are probably only “passenger” events. Because the treatment response of adult T-ALL is significantly poorer than that of childhood T-ALL and because exon 6 IL7R mutations play a role in the pathogenesis of childhood T-ALL, we sought to determine how the pattern of IL7R mutations varies between adult and childhood T-ALL. To that end, we sequenced the 50-base pair interval in exon 6 of the IL7R of DNA obtained from bone marrow samples of 35 randomly selected adult patients with T-ALL. Our analysis revealed that none of these 35 samples carried an IL7R mutation in exon 6. Whether differences in the genetic makeup of adult and childhood T-ALL explain the differential response to therapy remains to be determined

  7. CD98 Heavy Chain Is a Potent Positive Regulator of CD4+ T Cell Proliferation and Interferon-γ Production In Vivo.

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    Takeshi Kurihara

    Full Text Available Upon their recognition of antigens presented by the MHC, T cell proliferation is vital for clonal expansion and the acquisition of effector functions, which are essential for mounting adaptive immune responses. The CD98 heavy chain (CD98hc, Slc3a2 plays a crucial role in the proliferation of both CD4+ and CD8+ T cells, although it is unclear if CD98hc directly regulates the T cell effector functions that are not linked with T cell proliferation in vivo. Here, we demonstrate that CD98hc is required for both CD4+ T cell proliferation and Th1 functional differentiation. T cell-specific deletion of CD98hc did not affect T cell development in the thymus. CD98hc-deficient CD4+ T cells proliferated in vivo more slowly as compared with control T cells. C57BL/6 mice lacking CD98hc in their CD4+ T cells could not control Leishmania major infections due to lowered IFN-γ production, even with massive CD4+ T cell proliferation. CD98hc-deficient CD4+ T cells exhibited lower IFN-γ production compared with wild-type T cells, even when comparing IFN-γ expression in cells that underwent the same number of cell divisions. Therefore, these data indicate that CD98hc is required for CD4+ T cell expansion and functional Th1 differentiation in vivo, and suggest that CD98hc might be a good target for treating Th1-mediated immune disorders.

  8. miR-198 Represses the Proliferation of HaCaT Cells by Targeting Cyclin D2

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    Jian Wang

    2015-07-01

    Full Text Available Background: MiR-198 has been considered as an inhibitor of cell proliferation, invasion, migration and a promoter of apoptosis in most cancer cells, while its effect on non-cancer cells is poorly understood. Methods: The effect of miR-198 transfection on HaCaT cell proliferation was firstly detected using Cell Count Kit-8 and the cell cycle progression was analyzed by flow cytometry. Using bioinformatics analyses and luciferase assay, a new target of miR-198 was searched and identified. Then, the effect of the new target gene of miR-198 on cell proliferation and cell cycle was also detected. Results: Here we showed that miR-198 directly bound to the 3′-UTR of CCND2 mRNA, which was a key regulator in cell cycle progression. Overexpressed miR-198 repressed CCND2 expression at mRNA and protein levels and subsequently led to cell proliferation inhibition and cell cycle arrest in the G1 phase. Transfection ofSiCCND2 in HaCaT cells showed similar inhibitory effects on cell proliferation and cell cycle progression. Conclusion: In conclusion, we have identified that miR-198 inhibited HaCaT cell proliferation by directly targeting CCND2.

  9. Can resting B cells present antigen to T cells

    International Nuclear Information System (INIS)

    Ashwell, J.D.; DeFranco, A.L.; Paul, W.E.; Schwartz, R.H.

    1985-01-01

    Antigen stimulation of T lymphocytes can occur only in the presence of an antigen-presenting cell (APC). An ever-increasing number of cell types have been found to act as APCs; these include macrophages, splenic and lymph node dendritic cells, and Langerhans cells of the skin. Although activated B lymphocytes and B cell lymphomas are known to serve as APCs, it has been generally believed that resting B cells cannot perform this function. However, in recent studies the authors have found that resting B cells can indeed present soluble antigen to T cell clones as well as to antigen-primed T cells. The previous difficulty in demonstrating this activity can be explained by the finding that, in contrast to macrophages and dendritic cells, the antigen-presenting ability of resting B cells is very radiosensitive. Macrophages are usually irradiated with 2000-3300 rads to prevent them from incorporating [ 3 H]thymidine in the T cell proliferation assay. Resting B cells, however, begin to lose presenting function at 1500 rads and have completely lost this activity at 3300 rads. It was also possible to distinguish two distinct T cell clonal phenotypes when resting B cells were used as APCs on the basis of two different assays (T cell proliferation, and B cell proliferation resulting from T cell activation). The majority of T cell clones tested were capable of both proliferating themselves and inducing the proliferation of B cells. Some T cells clones, however, could not proliferate in the presence of antigen and B cell APCs, although they were very good at inducing the proliferation of B cells

  10. Modeling T-cell proliferation: an investigation of the consequences of the Hayflick limit.

    Science.gov (United States)

    Pilyugin, S; Mittler, J; Antia, R

    1997-05-07

    Somatic cells, including immune cells such as T-cells have a limited capacity for proliferation and can only replicate for a finite number of generations (known as the Hayflick limit) before dying. In this paper we use mathematical models to investigate the consequences of introducing a Hayflick limit on the dynamics of T-cells stimulated with specific antigen. We show that while the Hayflick limit does not alter the dynamics of T-cell response to antigen over the short term, it may have a profound effect on the long-term immune response. In particular we show that over the long term the Hayflick limit may be important in determining whether an immune response can be maintained to a persistent antigen (or parasite). The eventual outcome is determined by the magnitude of the Hayflick limit, the extent to which antigen reduces the input of T-cells from the thymus, and the rate of antigen-induced proliferation of T-cells. Counter to what might be expected we show that the persistence of an immune response (immune memory) requires the density of persistent antigen to be less than a defined threshold value. If the amount of persistent antigen (or parasite) is greater than this threshold value then immune memory will be relatively short lived. The consequences of this threshold for persistent mycobacterial and HIV infections and for the generation of vaccines are discussed.

  11. Ghrelin inhibits proliferation and increases T-type Ca2+ channel expression in PC-3 human prostate carcinoma cells

    International Nuclear Information System (INIS)

    Diaz-Lezama, Nundehui; Hernandez-Elvira, Mariana; Sandoval, Alejandro; Monroy, Alma; Felix, Ricardo; Monjaraz, Eduardo

    2010-01-01

    Research highlights: → Ghrelin decreases prostate carcinoma PC-3 cells proliferation. → Ghrelin favors apoptosis in PC-3 cells. → Ghrelin increase in intracellular free Ca 2+ levels in PC-3 cells. → Grelin up-regulates expression of T-type Ca 2+ channels in PC-3 cells. → PC-3 cells express T-channels of the Ca V 3.1 and Ca V 3.2 subtype. -- Abstract: Ghrelin is a multifunctional peptide hormone with roles in growth hormone release, food intake and cell proliferation. With ghrelin now recognized as important in neoplastic processes, the aim of this report is to present findings from a series of in vitro studies evaluating the cellular mechanisms involved in ghrelin regulation of proliferation in the PC-3 human prostate carcinoma cells. The results showed that ghrelin significantly decreased proliferation and induced apoptosis. Consistent with a role in apoptosis, an increase in intracellular free Ca 2+ levels was observed in the ghrelin-treated cells, which was accompanied by up-regulated expression of T-type voltage-gated Ca 2+ channels. Interestingly, T-channel antagonists were able to prevent the effects of ghrelin on cell proliferation. These results suggest that ghrelin inhibits proliferation and may promote apoptosis by regulating T-type Ca 2+ channel expression.

  12. FBXW7 regulates glucocorticoid response in T-cell acute lymphoblastic leukaemia by targeting the glucocorticoid receptor for degradation.

    Science.gov (United States)

    Malyukova, A; Brown, S; Papa, R; O'Brien, R; Giles, J; Trahair, T N; Dalla Pozza, L; Sutton, R; Liu, T; Haber, M; Norris, M D; Lock, R B; Sangfelt, O; Marshall, G M

    2013-04-01

    Loss of function mutation in FBXW7, an E3 ubiquitin ligase, is associated with good prognosis and early glucocorticoid treatment response in childhood T-cell acute lymphoblastic leukemia (T-ALL) by unknown mechanisms. Here, we show that FBXW7 targets the glucocorticoid receptor α (GRα) for ubiquitylation and proteasomal degradation in a manner dependent on glycogen synthase kinase 3 β-mediated phsophorylation. FBXW7 inactivation caused elevated GRα levels, and enhanced the transcriptional response to glucocorticoids. There was significant enhancement of GR transcriptional responses in FBXW7-deficient cell lines and primary T-ALL samples, in particular, for those pro-apoptotic regulatory proteins, BIM and PUMA. Reduced FBXW7 expression or function promoted glucocorticoid sensitivity, but not sensitivity to other chemotherapeutic agents used in T-ALL. Moreover, this was a general feature of different cancer cell types. Taken together, our work defines GRα as a novel FBXW7 substrate and demonstrates that favorable patient prognosis in T-ALL is associated with FBXW7 mutations due to enhanced GRα levels and steroid sensitivity. These findings suggest that inactivation of FBXW7, a putative tumor suppressor protein, may create a synthetic lethal state in the presence of specific anticancer therapies.

  13. Effective control of acute myeloid leukaemia and acute lymphoblastic leukaemia progression by telomerase specific adoptive T-cell therapy.

    Science.gov (United States)

    Sandri, Sara; De Sanctis, Francesco; Lamolinara, Alessia; Boschi, Federico; Poffe, Ornella; Trovato, Rosalinda; Fiore, Alessandra; Sartori, Sara; Sbarbati, Andrea; Bondanza, Attilio; Cesaro, Simone; Krampera, Mauro; Scupoli, Maria T; Nishimura, Michael I; Iezzi, Manuela; Sartoris, Silvia; Bronte, Vincenzo; Ugel, Stefano

    2017-10-20

    Telomerase (TERT) is a ribonucleoprotein enzyme that preserves the molecular organization at the ends of eukaryotic chromosomes. Since TERT deregulation is a common step in leukaemia, treatments targeting telomerase might be useful for the therapy of hematologic malignancies. Despite a large spectrum of potential drugs, their bench-to-bedside translation is quite limited, with only a therapeutic vaccine in the clinic and a telomerase inhibitor at late stage of preclinical validation. We recently demonstrated that the adoptive transfer of T cell transduced with an HLA-A2-restricted T-cell receptor (TCR), which recognize human TERT with high avidity, controls human B-cell chronic lymphocytic leukaemia (B-CLL) progression without severe side-effects in humanized mice. In the present report, we show the ability of our approach to limit the progression of more aggressive leukemic pathologies, such as acute myeloid leukaemia (AML) and B-cell acute lymphoblastic leukaemia (B-ALL). Together, our findings demonstrate that TERT-based adoptive cell therapy is a concrete platform of T cell-mediated immunotherapy for leukaemia treatment.

  14. Immunophenotype and increased presence of CD4(+)CD25(+) regulatory T cells in patients with acute lymphoblastic leukemia.

    Science.gov (United States)

    Wu, Cui-Ping; Qing, Xi; Wu, Cui-Yun; Zhu, Hong; Zhou, Hai-Yan

    2012-02-01

    Acute lymphoblastic leukemia (ALL), cancer of the white blood cells, is a heterogeneous disease that mainly occurs due to the malignant cloning of original and naive lymphocytes. The aim of this study was to explore the immunophenotype, the percentage of CD4(+)CD25(+) regulatory T cells (Tregs) and the expression of cytokines interleukin (IL)-2, IL-10 and TGF-β in patients with ALL. The immunophenotype and levels of CD4(+)CD25(+) Tregs were detected using flow cytometry in the peripheral blood of 35 ALL patients, with 18 healthy individuals being selected as controls. The results suggested that 22 patients had B cell ALL (B-ALL) and 13 had T cell ALL (T-ALL) among the 35 ALL patients. In B-ALL patients, the surface antigen CD19 was most commonly expressed; in T-ALL patients, CD7 was most common. Furthermore, the percentage of CD4(+)CD25(+) Treg cells in the peripheral blood of B-ALL and T-ALL patients was higher compared to that of healthy individuals (Pcell culture supernatants from B-ALL and T-ALL patients were higher compared to those in the controls (Pcells, IL-2, IL-10 or TGF-β in B-ALL versus T-ALL patients. The authors concluded that CD19 and CD7 may serve as diagnostic markers of B-ALL and T-ALL, respectively. The increased presence of CD4(+)CD25(+) Treg cells and the altered levels of secreted cytokines are indicative of an immunosuppressive mechanism in the pathogenesis of ALL.

  15. An "off-the-shelf" fratricide-resistant CAR-T for the treatment of T cell hematologic malignancies.

    Science.gov (United States)

    Cooper, Matthew L; Choi, Jaebok; Staser, Karl; Ritchey, Julie K; Devenport, Jessica M; Eckardt, Kayla; Rettig, Michael P; Wang, Bing; Eissenberg, Linda G; Ghobadi, Armin; Gehrs, Leah N; Prior, Julie L; Achilefu, Samuel; Miller, Christopher A; Fronick, Catrina C; O'Neal, Julie; Gao, Feng; Weinstock, David M; Gutierrez, Alejandro; Fulton, Robert S; DiPersio, John F

    2018-02-20

    T cell malignancies represent a group of hematologic cancers with high rates of relapse and mortality in patients for whom no effective targeted therapies exist. The shared expression of target antigens between chimeric antigen receptor (CAR) T cells and malignant T cells has limited the development of CAR-T because of unintended CAR-T fratricide and an inability to harvest sufficient autologous T cells. Here, we describe a fratricide-resistant "off-the-shelf" CAR-T (or UCART7) that targets CD7+ T cell malignancies and, through CRISPR/Cas9 gene editing, lacks both CD7 and T cell receptor alpha chain (TRAC) expression. UCART7 demonstrates efficacy against human T cell acute lymphoblastic leukemia (T-ALL) cell lines and primary T-ALL in vitro and in vivo without the induction of xenogeneic GvHD. Fratricide-resistant, allo-tolerant "off-the-shelf" CAR-T represents a strategy for treatment of relapsed and refractory T-ALL and non-Hodgkin's T cell lymphoma without a requirement for autologous T cells.

  16. Alisertib in Combination With Vorinostat in Treating Patients With Relapsed or Recurrent Hodgkin Lymphoma, B-Cell Non-Hodgkin Lymphoma, or Peripheral T-Cell Lymphoma

    Science.gov (United States)

    2018-04-10

    Adult B Acute Lymphoblastic Leukemia; Adult T Acute Lymphoblastic Leukemia; Anaplastic Large Cell Lymphoma; Angioimmunoblastic T-Cell Lymphoma; Chronic Lymphocytic Leukemia; Extranodal Marginal Zone Lymphoma of Mucosa-Associated Lymphoid Tissue; Hepatosplenic T-Cell Lymphoma; Intraocular Lymphoma; Lymphomatous Involvement of Non-Cutaneous Extranodal Site; Mature T-Cell and NK-Cell Non-Hodgkin Lymphoma; Nodal Marginal Zone Lymphoma; Primary Cutaneous B-Cell Non-Hodgkin Lymphoma; Recurrent Adult Acute Lymphoblastic Leukemia; Recurrent Adult Burkitt Lymphoma; Recurrent Adult Grade III Lymphomatoid Granulomatosis; Recurrent Adult Hodgkin Lymphoma; Recurrent Adult Immunoblastic Lymphoma; Recurrent Adult Lymphoblastic Lymphoma; Recurrent Adult T-Cell Leukemia/Lymphoma; Recurrent Grade 1 Follicular Lymphoma; Recurrent Grade 2 Follicular Lymphoma; Recurrent Grade 3 Follicular Lymphoma; Recurrent Mantle Cell Lymphoma; Recurrent Marginal Zone Lymphoma; Recurrent Mycosis Fungoides and Sezary Syndrome; Recurrent Non-Hodgkin Lymphoma; Recurrent Primary Cutaneous T-Cell Non-Hodgkin Lymphoma; Recurrent Small Lymphocytic Lymphoma; Refractory Chronic Lymphocytic Leukemia; Refractory Hairy Cell Leukemia; Small Intestinal Lymphoma; Splenic Marginal Zone Lymphoma; T-Cell Large Granular Lymphocyte Leukemia; Testicular Lymphoma; Waldenstrom Macroglobulinemia

  17. Precursor T-cell acute lymphoblastic leukemia presenting with bone marrow necrosis: a case report

    Directory of Open Access Journals (Sweden)

    Khoshnaw Najmaddin SH

    2012-10-01

    Full Text Available Abstract Introduction Bone marrow necrosis is a clinicopathological condition diagnosed most often at postmortem examination, but it is also seen during the course of malignancy and is not always associated with a poor prognosis. The morphological features of bone marrow necrosis are disruption of the normal marrow architecture and necrosis of myeloid tissue and medullary stroma. Non-malignant conditions associated with bone marrow necrosis are sickle cell anemia, infections, drugs (sulfasalazine, interferon α, all-trans retinoic acid, granulocyte colony-stimulating factor and fludarabine, disseminated intravascular coagulation, antiphospholipid antibody syndrome and acute graft versus host diseases. The malignant causes are leukemia, lymphoma and metastatic carcinomas. Herein we report the case of a patient with precursor T-cell acute lymphoblastic leukemia and bone marrow necrosis at initial presentation. Case presentation A 10-year-old Kurdish boy was presented with generalized bone pain and fever of 1 month’s duration which was associated with sweating, easy fatigability, nose bleeding, breathlessness and severe weight loss. On examination, we observed pallor, tachypnea, tachycardia, low blood pressure, fever, petechial hemorrhage, ecchymoses, tortuous dilated veins over the chest and upper part of abdomen, multiple small cervical lymph node enlargements, mildly enlarged spleen, palpable liver and gross abdominal distention. Blood analysis revealed pancytopenia and elevated lactate dehydrogenase and erythrocyte sedimentation rate. Imaging results showed mediastinal widening on a planar chest X-ray and diffuse focal infiltration of the axial bone marrow on magnetic resonance imaging of the lumbosacral vertebrae. Bone marrow aspiration and biopsy examination showed extensive bone marrow necrosis. Immunophenotyping analysis of the bone marrow biopsy confirmed T-cell acute lymphoblastic leukemia, as CD3 and terminal deoxynucleotidyl

  18. MS4a4B, a CD20 homologue in T cells, inhibits T cell propagation by modulation of cell cycle.

    Directory of Open Access Journals (Sweden)

    Hui Xu

    2010-11-01

    Full Text Available MS4a4B, a CD20 homologue in T cells, is a novel member of the MS4A gene family in mice. The MS4A family includes CD20, FcεRIβ, HTm4 and at least 26 novel members that are characterized by their structural features: with four membrane-spanning domains, two extracellular domains and two cytoplasmic regions. CD20, FcεRIβ and HTm4 have been found to function in B cells, mast cells and hematopoietic cells respectively. However, little is known about the function of MS4a4B in T cell regulation. We demonstrate here that MS4a4B negatively regulates mouse T cell proliferation. MS4a4B is highly expressed in primary T cells, natural killer cells (NK and some T cell lines. But its expression in all malignant T cells, including thymoma and T hybridoma tested, was silenced. Interestingly, its expression was regulated during T cell activation. Viral vector-driven overexpression of MS4a4B in primary T cells and EL4 thymoma cells reduced cell proliferation. In contrast, knockdown of MS4a4B accelerated T cell proliferation. Cell cycle analysis showed that MS4a4B regulated T cell proliferation by inhibiting entry of the cells into S-G2/M phase. MS4a4B-mediated inhibition of cell cycle was correlated with upregulation of Cdk inhibitory proteins and decreased levels of Cdk2 activity, subsequently leading to inhibition of cell cycle progression. Our data indicate that MS4a4B negatively regulates T cell proliferation. MS4a4B, therefore, may serve as a modulator in the negative-feedback regulatory loop of activated T cells.

  19. MS4a4B, a CD20 homologue in T cells, inhibits T cell propagation by modulation of cell cycle.

    Science.gov (United States)

    Xu, Hui; Yan, Yaping; Williams, Mark S; Carey, Gregory B; Yang, Jingxian; Li, Hongmei; Zhang, Guang-Xian; Rostami, Abdolmohamad

    2010-11-01

    MS4a4B, a CD20 homologue in T cells, is a novel member of the MS4A gene family in mice. The MS4A family includes CD20, FcεRIβ, HTm4 and at least 26 novel members that are characterized by their structural features: with four membrane-spanning domains, two extracellular domains and two cytoplasmic regions. CD20, FcεRIβ and HTm4 have been found to function in B cells, mast cells and hematopoietic cells respectively. However, little is known about the function of MS4a4B in T cell regulation. We demonstrate here that MS4a4B negatively regulates mouse T cell proliferation. MS4a4B is highly expressed in primary T cells, natural killer cells (NK) and some T cell lines. But its expression in all malignant T cells, including thymoma and T hybridoma tested, was silenced. Interestingly, its expression was regulated during T cell activation. Viral vector-driven overexpression of MS4a4B in primary T cells and EL4 thymoma cells reduced cell proliferation. In contrast, knockdown of MS4a4B accelerated T cell proliferation. Cell cycle analysis showed that MS4a4B regulated T cell proliferation by inhibiting entry of the cells into S-G2/M phase. MS4a4B-mediated inhibition of cell cycle was correlated with upregulation of Cdk inhibitory proteins and decreased levels of Cdk2 activity, subsequently leading to inhibition of cell cycle progression. Our data indicate that MS4a4B negatively regulates T cell proliferation. MS4a4B, therefore, may serve as a modulator in the negative-feedback regulatory loop of activated T cells.

  20. CD8+ T cells induce thyroid epithelial cell hyperplasia and fibrosis.

    Science.gov (United States)

    Yu, Shiguang; Fang, Yujiang; Sharav, Tumenjargal; Sharp, Gordon C; Braley-Mullen, Helen

    2011-02-15

    CD8(+) T cells can be important effector cells in autoimmune inflammation, generally because they can damage target cells by cytotoxicity. This study shows that activated CD8(+) T cells induce thyroid epithelial cell hyperplasia and proliferation and fibrosis in IFN-γ(-/-) NOD.H-2h4 SCID mice in the absence of CD4(+) T cells. Because CD8(+) T cells induce proliferation rather than cytotoxicity of target cells, these results describe a novel function for CD8(+) T cells in autoimmune disease. In contrast to the ability of purified CD8(+) T cells to induce thyrocyte proliferation, CD4(+) T cells or CD8 T cell-depleted splenocytes induced only mild thyroid lesions in SCID recipients. T cells in both spleens and thyroids highly produce TNF-α. TNF-α promotes proliferation of thyrocytes in vitro, and anti-TNF-α inhibits development of thyroid epithelial cell hyperplasia and proliferation in SCID recipients of IFN-γ(-/-) splenocytes. This suggests that targeting CD8(+) T cells and/or TNF-α may be effective for treating epithelial cell hyperplasia and fibrosis.

  1. Contribution of herpesvirus specific CD8 T cells to anti-viral T cell response in humans.

    Directory of Open Access Journals (Sweden)

    Elena Sandalova

    Full Text Available Herpesviruses infect most humans. Their infections can be associated with pathological conditions and significant changes in T cell repertoire but evidences of symbiotic effects of herpesvirus latency have never been demonstrated. We tested the hypothesis that HCMV and EBV-specific CD8 T cells contribute to the heterologous anti-viral immune response. Volume of activated/proliferating virus-specific and total CD8 T cells was evaluated in 50 patients with acute viral infections: 20 with HBV, 12 with Dengue, 12 with Influenza, 3 with Adenovirus infection and 3 with fevers of unknown etiology. Virus-specific (EBV, HCMV, Influenza pentamer+ and total CD8 T cells were analyzed for activation (CD38/HLA-DR, proliferation (Ki-67/Bcl-2(low and cytokine production. We observed that all acute viral infections trigger an expansion of activated/proliferating CD8 T cells, which differs in size depending on the infection but is invariably inflated by CD8 T cells specific for persistent herpesviruses (HCMV/EBV. CD8 T cells specific for other non-related non persistent viral infection (i.e. Influenza were not activated. IL-15, which is produced during acute viral infections, is the likely contributing mechanism driving the selective activation of herpesvirus specific CD8 T cells. In addition we were able to show that herpesvirus specific CD8 T cells displayed an increased ability to produce the anti-viral cytokine interferon-gamma during the acute phase of heterologous viral infection. Taken together, these data demonstrated that activated herpesvirus specific CD8 T cells inflate the activated/proliferating CD8 T cells population present during acute viral infections in human and can contribute to the heterologous anti-viral T cell response.

  2. Intrathymic lymphopoiesis: stromal cell-associated proliferation of T cells is independent of lymphocyte genotype.

    Science.gov (United States)

    Kyewski, B A; Travis, M; Kaplan, H S

    1984-09-01

    We analyzed the genetic restriction of direct cell-cell interactions between thymocytes and a) cortical epithelial cells, b) macrophages, and c) medullary dendritic cells in the mouse thymus. Thymectomized (C3H X C57BL/Ka)F1 hybrid mice were doubly grafted with P1 and P2 neonatal thymus grafts, were lethally irradiated, and were reconstituted with a mixture of P1 and P2 bone marrow cells which differed in the Thy-1 locus. The contributions of both parental inocula to the composition of the free and stromal cell-associated T cell compartments were analyzed separately in thymic grafts of each parental strain. The lymphoid composition in both compartments essentially reflected the peripheral T cell-chimerism in the host. The development of lymphostromal complexes was not restricted by the genotype of the partner cells. Statistical analysis of the distributions of P1 and P2 T cells among free thymocytes and within individual lymphostromal complexes, however, suggests that the T cells of an individual complex are the progeny of oligoclonal proliferation. Thus, both epithelial cells and bone marrow-derived stromal cells seem to be involved in different stages of intrathymic lymphopoiesis.

  3. Increased regulatory T cells in acute lymphoblastic leukemia patients.

    Science.gov (United States)

    Idris, Siti-Zuleha; Hassan, Norfarazieda; Lee, Le-Jie; Md Noor, Sabariah; Osman, Raudhawati; Abdul-Jalil, Marsitah; Nordin, Abdul-Jalil; Abdullah, Maha

    2015-10-01

    Regulation in adaptive immune response balances a fine line that prevents instigation of self-damage or fall into unresponsiveness permitting abnormal cell growth. Mechanisms that keep this balance in check include regulatory T cells (Tregs). Tregs consist of a small but heterogeneous population which may be identified by the phenotype, CD3+CD4+CD25+CD127-. Role of Tregs in pathogenesis of cancers is thus far supported by evidence of increased Tregs in various cancers and may contribute to poorer prognosis. Tregs may also be important in acute leukemias. A review of the literature on Tregs in acute leukemias was conducted and Tregs were determined in B-cell acute lymphoblastic leukemias (ALLs). Studies on Tregs in B-cell ALL are few and controversial. We observed a significantly increased percentage of Tregs (mean ± SD, 9.72 ± 3.79% vs. 7.05 ± 1.74%; P = 0.047) in the bone marrow/peripheral blood of ALL (n = 17) compared to peripheral blood of normal controls (n = 35). A positive trend between Tregs and age (R = 0.474, P = 0.055, n = 17) implicates this factor of poor prognosis in B-cell ALL. Tregs in cancer are particularly significant in immunotherapy. The manipulation of the immune system to treat cancer has for a long time ignored regulatory mechanisms inducible or in place. In lymphoma studies tumor-specific mechanisms that are unlike conventional methods in the induction of Tregs have been hypothesized. In addition, tumor-infiltrating Tregs may present different profiles from peripheral blood pictures. Tregs will continue to be dissected to reveal their mysteries and their impact on clinical significance.

  4. The TAL1 complex targets the FBXW7 tumor suppressor by activating miR-223 in human T cell acute lymphoblastic leukemia

    OpenAIRE

    Mansour, Marc R.; Sanda, Takaomi; Lawton, Lee N.; Li, Xiaoyu; Kreslavsky, Taras; Novina, Carl D.; Brand, Marjorie; Gutierrez, Alejandro; Kelliher, Michelle A.; Jamieson, Catriona H.M.; von Boehmer, Harald; Young, Richard A.; Look, A. Thomas

    2013-01-01

    The oncogenic transcription factor TAL1/SCL is aberrantly expressed in 60% of cases of human T cell acute lymphoblastic leukemia (T-ALL) and initiates T-ALL in mouse models. By performing global microRNA (miRNA) expression profiling after depletion of TAL1, together with genome-wide analysis of TAL1 occupancy by chromatin immunoprecipitation coupled to massively parallel DNA sequencing, we identified the miRNA genes directly controlled by TAL1 and its regulatory partners HEB, E2A, LMO1/2, GAT...

  5. [Autologous regulatory T cells can suppress the proliferation of lymphoma cell line in vitro].

    Science.gov (United States)

    Ying, Zhi-Tao; Guo, Jun; Ren, Jun; Kong, Yan; Yuan, Zhi-Hong; Liu, Xi-Juan; Zhang, Chen; Zheng, Wen; Song, Yu-Qin; Zhang, Yun-Tao; Zhu, Jun

    2009-06-01

    This study was aimed to investigate the suppressive effect of regulatory T (Treg) cells on the T cell lymphoma EL4 cell line and to explore its mechanism. C57BL/6 Mouse Treg cells were isolated by MACS (magnetic cell sorting). The purity and the expression of Foxp3 were detected by flow cytometry. The suppressive effect of sorted Treg cells on EL4 cells was detected by MTT assay. The secretion of TGF-beta1 and IL-10 was examined by enzyme-linked immunosorbent assay (ELISA). The results showed that CD4(+)CD25(+) T cells could be successfully isolated by MACS with the purity reaching 91.6% and the expression level of Foxp3 was 78.9%. The ratio of viable cells was more than 95%. Regulatory T cells could suppress the proliferation of EL4 cells effectively in the presence of antigen presenting cells (APCs). And the suppressive effect was most significant at 1:1 ratio. In addition, the suppression still existed without APCs. TGF-beta1 and IL-10 could not be detected by ELISA. It is concluded that the Treg cells can suppress T lymphoma cell in vitro. The suppressive effect of Treg cells works in dose-dependent manner, but not in cytokine-dependent manner. The mechanism of this suppression may take effect through cell-cell contact.

  6. Ghrelin inhibits proliferation and increases T-type Ca{sup 2+} channel expression in PC-3 human prostate carcinoma cells

    Energy Technology Data Exchange (ETDEWEB)

    Diaz-Lezama, Nundehui; Hernandez-Elvira, Mariana [Laboratory of Neuroendocrinology, Institute of Physiology, Autonomous University of Puebla (BUAP), Puebla (Mexico); Sandoval, Alejandro [School of Medicine FES Iztacala, National Autonomous University of Mexico (UNAM), Tlalnepantla (Mexico); Monroy, Alma; Felix, Ricardo [Department of Cell Biology, Center for Research and Advanced Studies of the National Polytechnic Institute (Cinvestav-IPN), Mexico City (Mexico); Monjaraz, Eduardo, E-mail: emguzman@siu.buap.mx [Laboratory of Neuroendocrinology, Institute of Physiology, Autonomous University of Puebla (BUAP), Puebla (Mexico)

    2010-12-03

    Research highlights: {yields} Ghrelin decreases prostate carcinoma PC-3 cells proliferation. {yields} Ghrelin favors apoptosis in PC-3 cells. {yields} Ghrelin increase in intracellular free Ca{sup 2+} levels in PC-3 cells. {yields} Grelin up-regulates expression of T-type Ca{sup 2+} channels in PC-3 cells. {yields} PC-3 cells express T-channels of the Ca{sub V}3.1 and Ca{sub V}3.2 subtype. -- Abstract: Ghrelin is a multifunctional peptide hormone with roles in growth hormone release, food intake and cell proliferation. With ghrelin now recognized as important in neoplastic processes, the aim of this report is to present findings from a series of in vitro studies evaluating the cellular mechanisms involved in ghrelin regulation of proliferation in the PC-3 human prostate carcinoma cells. The results showed that ghrelin significantly decreased proliferation and induced apoptosis. Consistent with a role in apoptosis, an increase in intracellular free Ca{sup 2+} levels was observed in the ghrelin-treated cells, which was accompanied by up-regulated expression of T-type voltage-gated Ca{sup 2+} channels. Interestingly, T-channel antagonists were able to prevent the effects of ghrelin on cell proliferation. These results suggest that ghrelin inhibits proliferation and may promote apoptosis by regulating T-type Ca{sup 2+} channel expression.

  7. The genomic landscape of pediatric and young adult T-lineage acute lymphoblastic leukemia | Office of Cancer Genomics

    Science.gov (United States)

    Genetic alterations that activate NOTCH1 signaling and T cell transcription factors, coupled with inactivation of the INK4/ARF tumor suppressors, are hallmarks of T-lineage acute lymphoblastic leukemia (T-ALL), but detailed genome-wide sequencing of large T-ALL cohorts has not been carried out. Using integrated genomic analysis of 264 T-ALL cases, we identified 106 putative driver genes, half of which had not previously been described in childhood T-ALL (for example, CCND3, CTCF, MYB, SMARCA4, ZFP36L2 and MYCN).

  8. Chemotherapy alters the increased numbers of myeloid-derived suppressor and regulatory T cells in children with acute lymphoblastic leukemia.

    Science.gov (United States)

    Salem, Mohamed Labib; El-Shanshory, Mohamed R; Abdou, Said H; Attia, Mohamed S; Sobhy, Shymaa M; Zidan, Mona F; Zidan, Abdel-Aziz A

    2018-04-01

    Acute lymphoblastic leukemia (ALL) is the most common cancer diagnosed in children. The precise mechanism behind the relapse in this disease is not clearly known. One possible mechanism could be the accumulation of immunosuppressive cells, including myeloid-derived suppressor cells (MDSCs) and T regulatory cells (T regs ) which we and others have reported to mediate suppression of anti-tumor immune responses. In this study, we aimed to analyze the numbers of these cells in a population of B-ALL pediatric patients. Peripheral blood samples withdrawn from B-ALL pediatric patients (n = 45 before, during and after the induction phase of chemotherapy. Using multi parametric flow cytometric analysis. MDSCs were identified as Lin - HLA-DR - CD33 + CD11b + ; and T reg cells were defined as CD4 + CD25 + CD127 -/low . Early diagnosed B-ALL patients showed significant increases in the numbers of MDSCs and T regs as compared to healthy volunteers. During induction of chemotherapy, however, the patients showed higher and lower numbers of MDSCs and T reg cells, respectively as compared to early diagnosed patients (i.e., before chemotherapy). After induction of chemotherapy, the numbers of MDSCs and T reg cells showed higher increases and decreases, respectively as compared to the numbers in patients during chemotherapy. Our results indicate that B-ALL patients harbor high numbers of both MDSCs and T regs cells. This pilot study opens a new avenue to investigate the mechanism mediating the emergence of these cells on larger number of B-ALL patients at different treatment stages.

  9. Limit-dilution assay and clonal expansion of all T cells capable of proliferation

    Energy Technology Data Exchange (ETDEWEB)

    Chen, W.F.; Wilson, A.; Scollay, R.; Shortman, K. (Walter and Eliza Hall Inst. of Medical Research, Parkville (Australia))

    1982-08-13

    A limit-dilution microculture system is presented in which almost all mature T cells, cultured at a level of about 1 cell/well, grow and expand to clones averaging 60,000 cells over an 8-9 day period. Cloning efficiency is 70-100%, so the set of expanded clones is representative of the starting T-cell population. T cells of all Lyt phenotypes form clones of progeny cells. The system involves culture in flat-bottom microtitre trays, in the presence of concanavalin A as the initiating stimulus, together with appropriately irradiated spleen filler cells and a supplementary source of soluble T cell growth factors. The resultant clones may be screened for cytolytic function, as described in the accompanying paper. The system may be used to assay the level of T cells capable of expansion or precursor function (PTL-p) by using (/sup 3/H)TdR uptake as a readout for the presence or absence of proliferating clones. Analysis of the frequency of positive cultures shows a good fit to the expected Poisson distribution, with no evidence of complicating suppressor or helper effects.

  10. Limit-dilution assay and clonal expansion of all T cells capable of proliferation

    International Nuclear Information System (INIS)

    Chen, W.-F.; Wilson, A.; Scollay, R.; Shortman, K.

    1982-01-01

    A limit-dilution microculture system is presented in which almost all mature T cells, cultured at a level of about 1 cell/well, grow and expand to clones averaging 60,000 cells over an 8-9 day period. Cloning efficiency is 70-100%, so the set of expanded clones is representative of the starting T-cell population. T cells of all Lyt phenotypes form clones of progeny cells. The system involves culture in flat-bottom microtitre trays, in the presence of concanavalin A as the initiating stimulus, together with appropriately irradiated spleen filler cells and a supplementary source of soluble T cell growth factors. The resultant clones may be screened for cytolytic function, as described in the accompanying paper. The system may be used to assay the level of T cells capable of expansion or precursor function (PTL-p) by using [ 3 H]TdR uptake as a readout for the presence or absence of proliferating clones. Analysis of the frequency of positive cultures shows a good fit to the expected Poisson distribution, with no evidence of complicating suppressor or helper effects. (Auth.)

  11. Modification of T-cell antigenic properties of tetanus toxoid by SDS-PAGE separation. Implications for T-cell blotting

    DEFF Research Database (Denmark)

    Christensen, C B; Theander, T G

    1997-01-01

    Using Tetanus Toxoid (TT) as a model antigen the T-cell Blotting method was evaluated. Peripheral blood mononuclear cell (PBMC) cultures were stimulated by blotted nitrocellulose-bound TT or soluble TT. SDS-Poly-Acrylamide-Gel-Electrophoresis separated TT only induced proliferation in 20% of the ......Using Tetanus Toxoid (TT) as a model antigen the T-cell Blotting method was evaluated. Peripheral blood mononuclear cell (PBMC) cultures were stimulated by blotted nitrocellulose-bound TT or soluble TT. SDS-Poly-Acrylamide-Gel-Electrophoresis separated TT only induced proliferation in 20......% of the PBMC cultures whereas proliferation was induced in 79% of the same cultures offered similar treated TT (except for the PAGE separation). When T-cell blotting was performed with TT separated in a SDS-agarose matrix, proliferation was induced in 80% of donors responding to soluble TT. The results show...... that SDS-PAGE alters the ability of TT to induce T-cell proliferation, possibly due to unpolymerized acrylamide binding to proteins during SDS-PAGE. The use of SDS-PAGE T-cell blotting in the screening for T-cell antigens must therefore be reconsidered. We suggest the use of SDS-Agarose Gel Electrophoresis...

  12. GLYCAN-DIRECTED CAR-T CELLS.

    Science.gov (United States)

    Steentoft, Catharina; Migliorini, Denis; King, Tiffany R; Mandel, Ulla; June, Carl H; Posey, Avery D

    2018-01-23

    Cancer immunotherapy is rapidly advancing in the treatment of a variety of hematopoietic cancers, including pediatric acute lymphoblastic leukemia and diffuse large B cell lymphoma, with chimeric antigen receptor (CAR)-T cells. CARs are genetically encoded artificial T cell receptors that combine the antigen specificity of an antibody with the machinery of T cell activation. However, implementation of CAR technology in the treatment of solid tumors has been progressing much slower. Solid tumors are characterized by a number of challenges that need to be overcome, including cellular heterogeneity, immunosuppressive tumor microenvironment (TME), and, in particular, few known cancer-specific targets. Post-translational modifications that differentially occur in malignant cells generate valid cell surface, cancer-specific targets for CAR-T cells. We previously demonstrated that CAR-T cells targeting an aberrant O-glycosylation of MUC1, a common cancer marker associated with changes in cell adhesion, tumor growth, and poor prognosis, could control malignant growth in mouse models. Here, we discuss the field of glycan-directed CAR-T cells and review the different classes of antibodies specific for glycan-targeting, including the generation of high affinity O-glycopeptide antibodies. Finally, we discuss historic and recently investigated glycan targets for CAR-T cells and provide our perspective on how targeting the tumor glycoproteome and/or glycome will improve CAR-T immunotherapy. © The Author(s) 2018. Published by Oxford University Press. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

  13. Immunophenotype and increased presence of CD4+CD25+ regulatory T cells in patients with acute lymphoblastic leukemia

    OpenAIRE

    WU, CUI-PING; QING, XI; WU, CUI-YUN; ZHU, HONG; ZHOU, HAI-YAN

    2011-01-01

    Acute lymphoblastic leukemia (ALL), cancer of the white blood cells, is a heterogeneous disease that mainly occurs due to the malignant cloning of original and naive lymphocytes. The aim of this study was to explore the immunophenotype, the percentage of CD4+CD25+ regulatory T cells (Tregs) and the expression of cytokines interleukin (IL)-2, IL-10 and TGF-β in patients with ALL. The immunophenotype and levels of CD4+CD25+ Tregs were detected using flow cytometry in the peripheral blood of 35 ...

  14. SET-NUP214 fusion in acute myeloid leukemia- and T-cell acute lymphoblastic leukemia-derived cell lines

    Directory of Open Access Journals (Sweden)

    Zaborski Margarete

    2009-01-01

    Full Text Available Abstract Background SET-NUP214 fusion resulting from a recurrent cryptic deletion, del(9(q34.11q34.13 has recently been described in T-cell acute lymphoblastic leukemia (T-ALL and in one case of acute myeloid leukemia (AML. The fusion protein appears to promote elevated expression of HOXA cluster genes in T-ALL and may contribute to the pathogenesis of the disease. We screened a panel of ALL and AML cell lines for SET-NUP214 expression to find model systems that might help to elucidate the cellular function of this fusion gene. Results Of 141 human leukemia/lymphoma cell lines tested, only the T-ALL cell line LOUCY and the AML cell line MEGAL expressed the SET(TAF-Iβ-NUP214 fusion gene transcript. RT-PCR analysis specifically recognizing the alternative first exons of the two TAF-I isoforms revealed that the cell lines also expressed TAF-Iα-NUP214 mRNA. Results of fluorescence in situ hybridization (FISH and array-based copy number analysis were both consistent with del(9(q34.11q34.13 as described. Quantitative genomic PCR also confirmed loss of genomic material between SET and NUP214 in both cell lines. Genomic sequencing localized the breakpoints of the SET gene to regions downstream of the stop codon and to NUP214 intron 17/18 in both LOUCY and MEGAL cells. Both cell lines expressed the 140 kDa SET-NUP214 fusion protein. Conclusion Cell lines LOUCY and MEGAL express the recently described SET-NUP214 fusion gene. Of special note is that the formation of the SET exon 7/NUP214 exon 18 gene transcript requires alternative splicing as the SET breakpoint is located downstream of the stop codon in exon 8. The cell lines are promising model systems for SET-NUP214 studies and should facilitate investigating cellular functions of the the SET-NUP214 protein.

  15. Black seed oil ameliorates allergic airway inflammation by inhibiting T-cell proliferation in rats.

    Science.gov (United States)

    Shahzad, Muhammad; Yang, Xudong; Raza Asim, M B; Sun, Qingzhu; Han, Yan; Zhang, Fujun; Cao, Yongxiao; Lu, Shemin

    2009-02-01

    The black seeds, from the Ranunculaceae family, have been traditionally used by various cultures as a natural remedy for several ailments. In this study, we examined the effect of black seed oil as an immunomodulator in a rat model of allergic airway inflammation. Rats sensitized to ovalbumin and challenged intranasally with ovalbumin to induce an allergic inflammatory response were compared to ovalbumin-sensitized, intranasally ovalbumin-exposed rats pretreated with intraperitoneally administered black seed oil and to control rats. The levels of IgE, IgG1 and ova-specific T-cell proliferation in spleen were measured by ELISA. The pro-inflammatory cytokine IL-4, IL-5, IL-6 and TGF-beta1 mRNA expression levels were measured by reverse transcription polymerase chain reaction. The intraperitoneal administration of black seed oil inhibited the Th2 type immune response in rats by preventing inflammatory cell infiltration and pathological lesions in the lungs. It significantly decreased the nitric oxide production in BALF, total serum IgE, IgG1 and OVA-specific IgG1 along with IL-4, IL-5, IL-6 and TGF-beta1 mRNA expression. Black seed oil treatment resulted in decreased T-cell response evident by lesser delayed type hypersensitivity and lower T-cell proliferation in spleen. In conclusion, black seed oil exhibited a significant reduction in all the markers of allergic inflammation mainly by inhibiting the delayed type hypersensitivity and T-cell proliferation. The data suggests that inhibition of T-cell response may be responsible for immunomodulatory effect of black seed oil in the rat model of allergic airway inflammation.

  16. Hijacking T cell differentiation: new insights in TLX function in T-ALL.

    Science.gov (United States)

    King, Bryan; Ntziachristos, Panagiotis; Aifantis, Iannis

    2012-04-17

    TLX1 and TLX3 are two closely-related homeobox transcriptional repressors frequently misexpressed and translocated in T cell acute lymphoblastic leukemia (T-ALL). In this issue of Cancer Cell, Dadi et al. provide new insights into how these factors are recruited by ETS-1 to the TCRα enhancer and actively repress differentiation. Copyright © 2012 Elsevier Inc. All rights reserved.

  17. ZFX Controls Propagation and Prevents Differentiation of Acute T-Lymphoblastic and Myeloid Leukemia

    Directory of Open Access Journals (Sweden)

    Stuart P. Weisberg

    2014-02-01

    Full Text Available Tumor-propagating cells in acute leukemia maintain a stem/progenitor-like immature phenotype and proliferative capacity. Acute myeloid leukemia (AML and acute T-lymphoblastic leukemia (T-ALL originate from different lineages through distinct oncogenic events such as MLL fusions and Notch signaling, respectively. We found that Zfx, a transcription factor that controls hematopoietic stem cell self-renewal, controls the initiation and maintenance of AML caused by MLL-AF9 fusion and of T-ALL caused by Notch1 activation. In both leukemia types, Zfx prevents differentiation and activates gene sets characteristic of immature cells of the respective lineages. In addition, endogenous Zfx contributes to gene induction and transformation by Myc overexpression in myeloid progenitors. Key Zfx target genes include the mitochondrial enzymes Ptpmt1 and Idh2, whose overexpression partially rescues the propagation of Zfx-deficient AML. These results show that distinct leukemia types maintain their undifferentiated phenotype and self-renewal by exploiting a common stem-cell-related genetic regulator.

  18. Inhibitory effect of extracellular purine nucleotide and nucleoside concentrations on T cell proliferation

    Energy Technology Data Exchange (ETDEWEB)

    Weiler, Monica [Department of Medicine III and Transfusion Medicine, University Hospital Grosshadern, Ludwig-Maximilians-University, Munich (Germany); Schmetzer, Helga [Helmholtz Center Munich (Germany); German Research Center for Environmental Health, Munich (Germany); Braeu, Marion; Buhmann, Raymund [Helmholtz Center Munich (Germany); German Research Center for Environmental Health, Munich (Germany); Department of Medicine III and Transfusion Medicine, University Hospital Grosshadern, Ludwig-Maximilians-University, Munich (Germany)

    2016-11-15

    The release of nucleic acids and derivatives after tissue-injury may affect cellular immune-response. We studied the impact of extracellular ribo-, desoxyribonucleotides and nucleosides on T-cell immunity. Peripheral-blood-mononuclear-cells (PBMCs) or isolated CD3{sup +}T-cells obtained from 6 healthy donors were stimulated via CD3/CD28 Dynabeads or dendritic cells (DCs) in the presence or absence of pyrimidine-, purine-nucleotides and -nucleosides (range 2–200 µM). Addition of deoxy-, guanosine-triphosphate (dGTP, GTP) and guanosine resulted concentration dependent in a complete, adenosine-triphosphate (ATP) in a partial inhibition of the induced T-cell-proliferation. Deoxyadenosine-triphosphate (dATP), adenosine and the pyrimidine-ribo- and -deoxyribonucleotides displayed no inhibitory capacity. Inhibitory effects of dGTP and GTP, but not of guanosine and ATP were culture-media-dependent and could be almost abrogated by use of the serum-free lymphocyte-culture-media X-Vivo15 instead of RPMI1640 with standard-supplementation. In contrast to RPMI1640, X-Vivo15 resulted in a significant down-regulation of the cell-surface-located ectonucleotidases CD39 (Ecto-Apyrase) and CD73 (Ecto-5′-Nucleotidase), critical for the extracellular nucleotides-hydrolysis to nucleosides, explaining the loss of inhibition mediated by dGTP and GTP, but not Guanosine. In line with previous findings ATP was found to exert immunosuppressive effects on T-cell-proliferation. Purine-nucleotides, dGTP and GTP displayed a higher inhibitory capacity, but seem to be strictly dependent on the microenvironmental conditions modulating the responsiveness of the respective T-lymphocytes. Further evaluation of experimental and respective clinical settings should anticipate these findings.

  19. Inhibitory effect of extracellular purine nucleotide and nucleoside concentrations on T cell proliferation

    International Nuclear Information System (INIS)

    Weiler, Monica; Schmetzer, Helga; Braeu, Marion; Buhmann, Raymund

    2016-01-01

    The release of nucleic acids and derivatives after tissue-injury may affect cellular immune-response. We studied the impact of extracellular ribo-, desoxyribonucleotides and nucleosides on T-cell immunity. Peripheral-blood-mononuclear-cells (PBMCs) or isolated CD3 + T-cells obtained from 6 healthy donors were stimulated via CD3/CD28 Dynabeads or dendritic cells (DCs) in the presence or absence of pyrimidine-, purine-nucleotides and -nucleosides (range 2–200 µM). Addition of deoxy-, guanosine-triphosphate (dGTP, GTP) and guanosine resulted concentration dependent in a complete, adenosine-triphosphate (ATP) in a partial inhibition of the induced T-cell-proliferation. Deoxyadenosine-triphosphate (dATP), adenosine and the pyrimidine-ribo- and -deoxyribonucleotides displayed no inhibitory capacity. Inhibitory effects of dGTP and GTP, but not of guanosine and ATP were culture-media-dependent and could be almost abrogated by use of the serum-free lymphocyte-culture-media X-Vivo15 instead of RPMI1640 with standard-supplementation. In contrast to RPMI1640, X-Vivo15 resulted in a significant down-regulation of the cell-surface-located ectonucleotidases CD39 (Ecto-Apyrase) and CD73 (Ecto-5′-Nucleotidase), critical for the extracellular nucleotides-hydrolysis to nucleosides, explaining the loss of inhibition mediated by dGTP and GTP, but not Guanosine. In line with previous findings ATP was found to exert immunosuppressive effects on T-cell-proliferation. Purine-nucleotides, dGTP and GTP displayed a higher inhibitory capacity, but seem to be strictly dependent on the microenvironmental conditions modulating the responsiveness of the respective T-lymphocytes. Further evaluation of experimental and respective clinical settings should anticipate these findings.

  20. Fc receptors for mouse IgG1 on human monocytes: polymorphism and role in antibody-induced T cell proliferation.

    Science.gov (United States)

    Tax, W J; Hermes, F F; Willems, R W; Capel, P J; Koene, R A

    1984-09-01

    In previous studies, it was shown that there is polymorphism in the mitogenic effect of mouse IgG1 monoclonal antibodies against the T3 antigen of human T cells. This polymorphism implies that IgG1 anti-T3 antibodies are not mitogenic for T cells from 30% of healthy individuals. The present results demonstrate that this polymorphism is caused by polymorphism of an Fc receptor for mouse IgG1, present on human monocytes. The Fc receptor for murine IgG1 could be detected by a newly developed rosetting assay on monocytes from all individuals responsive to the mitogenic effect of IgG1 anti-T3 antibodies. This Fc receptor was not detectable on monocytes from those individuals exhibiting no mitogenic responses to IgG1 anti-T3 monoclonal antibodies. Cross-linking of T3 antigens appears to be essential for antibody-induced mitosis of T cells, because mononuclear cells that did not proliferate in response to WT 31 (an IgG1 antibody against T3 antigen) showed a proliferative response to Sepharose beads coated with WT 31. The Fc receptor--if functionally present--may be involved in the cross-linking of T3 antigens through anti-T3 antibodies. Further evidence for the involvement of this Fc receptor in antibody-induced T cell proliferation was provided by inhibition studies. Immune complexes containing IgG1 antibodies were able to inhibit the proliferative response to IgG1 anti-T3 antibodies. This inhibition by immune complexes appears to be mediated through the monocyte Fc receptor for mouse IgG1. These findings are important for the interpretation of previously described inhibitory effects of anti-T cell monoclonal antibodies on T cell proliferation, and show that such inhibitory effects may be monocyte-mediated (via immune complexes) rather than caused by a direct involvement of the respective T cell antigens in T cell mitosis. The Fc receptor for mouse IgG1 plays a role in antibody-induced T cell proliferation. Its polymorphism may have important implications for the

  1. Co-infusion of haplo-identical CD19-chimeric antigen receptor T cells and stem cells achieved full donor engraftment in refractory acute lymphoblastic leukemia

    Directory of Open Access Journals (Sweden)

    Bo Cai

    2016-11-01

    Full Text Available Abstract Background Elderly patients with relapsed and refractory acute lymphoblastic leukemia (ALL have poor prognosis. Autologous CD19 chimeric antigen receptor-modified T (CAR-T cells have potentials to cure patients with B cell ALL; however, safety and efficacy of allogeneic CD19 CAR-T cells are still undetermined. Case presentation We treated a 71-year-old female with relapsed and refractory ALL who received co-infusion of haplo-identical donor-derived CD19-directed CAR-T cells and mobilized peripheral blood stem cells (PBSC following induction chemotherapy. Undetectable minimal residual disease by flow cytometry was achieved, and full donor cell engraftment was established. The transient release of cytokines and mild fever were detected. Significantly elevated serum lactate dehydrogenase, alanine transaminase, bilirubin and glutamic-oxalacetic transaminase were observed from days 14 to 18, all of which were reversible after immunosuppressive therapy. Conclusions Our preliminary results suggest that co-infusion of haplo-identical donor-derived CAR-T cells and mobilized PBSCs may induce full donor engraftment in relapsed and refractory ALL including elderly patients, but complications related to donor cell infusions should still be cautioned. Trial registration Allogeneic CART-19 for Elderly Relapsed/Refractory CD19+ ALL. NCT02799550

  2. A novel method to generate T-cell receptor-deficient chimeric antigen receptor T cells.

    Science.gov (United States)

    Kamiya, Takahiro; Wong, Desmond; Png, Yi Tian; Campana, Dario

    2018-03-13

    Practical methods are needed to increase the applicability and efficacy of chimeric antigen receptor (CAR) T-cell therapies. Using donor-derived CAR-T cells is attractive, but expression of endogenous T-cell receptors (TCRs) carries the risk for graft-versus-host-disease (GVHD). To remove surface TCRαβ, we combined an antibody-derived single-chain variable fragment specific for CD3ε with 21 different amino acid sequences predicted to retain it intracellularly. After transduction in T cells, several of these protein expression blockers (PEBLs) colocalized intracellularly with CD3ε, blocking surface CD3 and TCRαβ expression. In 25 experiments, median TCRαβ expression in T lymphocytes was reduced from 95.7% to 25.0%; CD3/TCRαβ cell depletion yielded virtually pure TCRαβ-negative T cells. Anti-CD3ε PEBLs abrogated TCRαβ-mediated signaling, without affecting immunophenotype or proliferation. In anti-CD3ε PEBL-T cells, expression of an anti-CD19-41BB-CD3ζ CAR induced cytokine secretion, long-term proliferation, and CD19 + leukemia cell killing, at rates meeting or exceeding those of CAR-T cells with normal CD3/TCRαβ expression. In immunodeficient mice, anti-CD3ε PEBL-T cells had markedly reduced GVHD potential; when transduced with anti-CD19 CAR, these T cells killed engrafted leukemic cells. PEBL blockade of surface CD3/TCRαβ expression is an effective tool to prepare allogeneic CAR-T cells. Combined PEBL and CAR expression can be achieved in a single-step procedure, is easily adaptable to current cell manufacturing protocols, and can be used to target other T-cell molecules to further enhance CAR-T-cell therapies. © 2018 by The American Society of Hematology.

  3. CXCL5 knockdown expression inhibits human bladder cancer T24 cells proliferation and migration

    Energy Technology Data Exchange (ETDEWEB)

    Zheng, Jiajia [Department of Laboratory Medicine, Peking University Third Hospital, Beijing (China); Zhu, Xi [Department of Urology, Beijing Friendship Hospital Affiliated to Capital Medical University, Beijing (China); Zhang, Jie, E-mail: zhangjiebjmu@163.com [Department of Laboratory Medicine, Peking University Third Hospital, Beijing (China)

    2014-03-28

    Highlights: • We first demonstrated CXCL5 is highly expressed in human bladder tumor tissues and cells. • CXCL5 knockdown inhibits proliferation, migration and promotes apoptosis in T24 cells. • CXCL5 knockdown inhibits Snail, PI3K-AKT and ERK1/2 signaling pathways in T24 cells. • CXCL5 is critical for bladder tumor growth and progression. - Abstract: CXCL5 (epithelial neutrophil activating peptide-78) which acts as a potent chemoattractant and activator of neutrophil function was reported to play a multifaceted role in tumorigenesis. To investigate the role of CXCL5 in bladder cancer progression, we examined the CXCL5 expression in bladder cancer tissues by real-time PCR and Western blot, additionally, we used shRNA-mediated silencing to generate stable CXCL5 silenced bladder cancer T24 cells and defined its biological functions. Our results demonstrated that mRNA and protein of CXCL5 is increased in human bladder tumor tissues and cell lines, down-regulation of CXCL5 in T24 cells resulted in significantly decreased cell proliferation, migration and increased cell apoptosis in vitro through Snail, PI3K-AKT and ERK1/2 signaling pathways. These data suggest that CXCL5 is critical for bladder tumor growth and progression, it may represent a potential application in cancer diagnosis and therapy.

  4. CXCL5 knockdown expression inhibits human bladder cancer T24 cells proliferation and migration

    International Nuclear Information System (INIS)

    Zheng, Jiajia; Zhu, Xi; Zhang, Jie

    2014-01-01

    Highlights: • We first demonstrated CXCL5 is highly expressed in human bladder tumor tissues and cells. • CXCL5 knockdown inhibits proliferation, migration and promotes apoptosis in T24 cells. • CXCL5 knockdown inhibits Snail, PI3K-AKT and ERK1/2 signaling pathways in T24 cells. • CXCL5 is critical for bladder tumor growth and progression. - Abstract: CXCL5 (epithelial neutrophil activating peptide-78) which acts as a potent chemoattractant and activator of neutrophil function was reported to play a multifaceted role in tumorigenesis. To investigate the role of CXCL5 in bladder cancer progression, we examined the CXCL5 expression in bladder cancer tissues by real-time PCR and Western blot, additionally, we used shRNA-mediated silencing to generate stable CXCL5 silenced bladder cancer T24 cells and defined its biological functions. Our results demonstrated that mRNA and protein of CXCL5 is increased in human bladder tumor tissues and cell lines, down-regulation of CXCL5 in T24 cells resulted in significantly decreased cell proliferation, migration and increased cell apoptosis in vitro through Snail, PI3K-AKT and ERK1/2 signaling pathways. These data suggest that CXCL5 is critical for bladder tumor growth and progression, it may represent a potential application in cancer diagnosis and therapy

  5. Different Competitive Capacities of Stat4 and Stat6 Deficient CD4+ T Cells during Lymphophenia-Driven Proliferation

    DEFF Research Database (Denmark)

    Sanchez-Guajardo, Vanesa Maria; Borghans, J.A.M.; Marquez, M.-E.

    2005-01-01

    The outcome of an immune response relies on the competitive capacities acquired through differentiation of CD4ﰀ T cells into Th1 or Th2 effector cells. Because Stat4 and Stat6 proteins are implicated in the Th1 vs Th2 generation and maintenance, respectively, we compare in this study the kinetics...... of Stat4ﰐ/ﰐ and Stat6ﰐ/ﰐ CD4ﰀ T cells during competitive bone marrow reconstitution and lymphopenia-driven proliferation. After bone marrow transplantation, both populations reconstitute the peripheral T cell pools equally well. After transfer into lymphopenic hosts, wild-type and Stat6ﰐ/ﰐ CD4ﰀ T cells...... show a proliferation advantage, which is early associated with the expression of an active phospho-Stat4 and the down-regulation of Stat6. Despite these differences, Stat4- and Stat6-deficient T cells reach similar steady state numbers. However, when both Stat4ﰐ/ﰐ and Stat6ﰐ/ﰐ CD4ﰀ T cells...

  6. Suppression of Human T Cell Proliferation Mediated by the Cathepsin B Inhibitor, z-FA-FMK Is Due to Oxidative Stress.

    Directory of Open Access Journals (Sweden)

    Tanuja Rajah

    Full Text Available The cathepsin B inhibitor, benzyloxycarbonyl-phenylalanine-alanine-fluoromethyl ketone (z-FA-FMK readily inhibits anti-CD3-induced human T cell proliferation, whereas the analogue benzyloxycarbonyl-phenylalanine-alanine-diazomethyl ketone (z-FA-DMK had no effect. In contrast, benzyloxycarbonyl-phenylalanine-alanine-chloromethyl ketone (z-FA-CMK was toxic. The inhibition of T cell proliferation mediated by z-FA-FMK requires not only the FMK moiety, but also the benzyloxycarbonyl group at the N-terminal, suggesting some degree of specificity in z-FA-FMK-induced inhibition of primary T cell proliferation. We showed that z-FA-FMK treatment leads to a decrease in intracellular glutathione (GSH with a concomitant increase in reactive oxygen species (ROS levels in activated T cells. The inhibition of anti-CD3-induced T cell proliferation mediated by z-FA-FMK was abolished by the presence of low molecular weight thiols such as GSH, N-acetylcysteine (NAC and L-cysteine, whereas D-cysteine which cannot be metabolised to GSH has no effect. The inhibition of anti-CD3-induced up-regulation of CD25 and CD69 expression mediated by z-FA-FMK was also attenuated in the presence of exogenous GSH. Similar to cell proliferation, GSH, NAC and L-cysteine but not D-cysteine, completely restored the processing of caspase-8 and caspase-3 to their respective subunits in z-FA-FMK-treated activated T cells. Our collective results demonstrated that the inhibition of T cell activation and proliferation mediated by z-FA-FMK is due to oxidative stress via the depletion of GSH.

  7. CD19 CAR-T cell therapy for relapsed/refractory acute lymphoblastic leukemia: factors affecting toxicities and long-term efficacies.

    Science.gov (United States)

    Zhang, Li-Na; Song, Yongping; Liu, Delong

    2018-03-15

    The prognosis of adults with relapsed/refractory (R/R) acute lymphoblastic leukemia (ALL) remains dismal even at this day and age. With salvage chemotherapy, only 29% (range 18 to 44%) of the patients with R/R ALL can be induced into complete remission (CR), with a median overall survival (OS) of 4 months (range 2-6 months). Blinatumomab and inotuzumab ozogamycin (IO) are immunotherapeutic agents that increased CR to 80% and extended survival to 7.7 months in this high-risk population of patients. In the last few years, chimeric antigen receptor (CAR)--engineered T cells have led to major progress in cancer immunotherapy. CD-19 CAR-T cells have been recently approved for high-risk R/R ALL and lymphoma. The data from long-term follow-up of a single-center phase I study of 19-28z CAR-T cell therapy for adult R/R ALL were just published. At the same time, a multicenter phase II study of 19-41BB CAR-T cell therapy for children and young adults with R/R B cell ALL was also published. The two studies provided fresh information with long-term follow-up. This research highlight analyzed the data and proposed future perspectives for further investigation in this rapidly evolving field.

  8. The Effects of Tacrolimus on T-Cell Proliferation Are Short-Lived: A Pilot Analysis of Immune Function Testing

    Directory of Open Access Journals (Sweden)

    Benjamin L. Laskin, MD, MS

    2017-08-01

    Conclusions. T-cell proliferation is currently not suitable to measure immunosuppression because sample processing diminishes observable effects. Future immune function testing should focus on fresh samples with minimal washing steps. Our results also emphasize the importance of adherence to immunosuppressive treatment, because T-cell proliferation recovered substantially after even brief discontinuation of tacrolimus.

  9. The inhibition of human T cell proliferation by the caspase inhibitor z-VAD-FMK is mediated through oxidative stress

    Energy Technology Data Exchange (ETDEWEB)

    Rajah, T.; Chow, S.C., E-mail: chow.sek.chuen@monash.edu

    2014-07-15

    The caspase inhibitor benzyloxycarbony (Cbz)-L-Val-Ala-Asp (OMe)-fluoromethylketone (z-VAD-FMK) has recently been shown to inhibit T cell proliferation without blocking caspase-8 and caspase-3 activation in primary T cells. We showed in this study that z-VAD-FMK treatment leads to a decrease in intracellular glutathione (GSH) with a concomitant increase in reactive oxygen species (ROS) levels in activated T cells. The inhibition of anti-CD3-mediated T cell proliferation induced by z-VAD-FMK was abolished by the presence of low molecular weight thiols such as GSH, N-acetylcysteine (NAC) and L-cysteine, whereas D-cysteine which cannot be metabolised to GSH has no effect. These results suggest that the depletion of intracellular GSH is the underlying cause of z-VAD-FMK-mediated inhibition of T cell activation and proliferation. The presence of exogenous GSH also attenuated the inhibition of anti-CD3-induced CD25 and CD69 expression mediated by z-VAD-FMK. However, none of the low molecular weight thiols were able to restore the caspase-inhibitory properties of z-VAD-FMK in activated T cells where caspase-8 and caspase-3 remain activated and processed into their respective subunits in the presence of the caspase inhibitor. This suggests that the inhibition of T cell proliferation can be uncoupled from the caspase-inhibitory properties of z-VAD-FMK. Taken together, the immunosuppressive effects in primary T cells mediated by z-VAD-FMK are due to oxidative stress via the depletion of GSH.

  10. The inhibition of human T cell proliferation by the caspase inhibitor z-VAD-FMK is mediated through oxidative stress

    International Nuclear Information System (INIS)

    Rajah, T.; Chow, S.C.

    2014-01-01

    The caspase inhibitor benzyloxycarbony (Cbz)-L-Val-Ala-Asp (OMe)-fluoromethylketone (z-VAD-FMK) has recently been shown to inhibit T cell proliferation without blocking caspase-8 and caspase-3 activation in primary T cells. We showed in this study that z-VAD-FMK treatment leads to a decrease in intracellular glutathione (GSH) with a concomitant increase in reactive oxygen species (ROS) levels in activated T cells. The inhibition of anti-CD3-mediated T cell proliferation induced by z-VAD-FMK was abolished by the presence of low molecular weight thiols such as GSH, N-acetylcysteine (NAC) and L-cysteine, whereas D-cysteine which cannot be metabolised to GSH has no effect. These results suggest that the depletion of intracellular GSH is the underlying cause of z-VAD-FMK-mediated inhibition of T cell activation and proliferation. The presence of exogenous GSH also attenuated the inhibition of anti-CD3-induced CD25 and CD69 expression mediated by z-VAD-FMK. However, none of the low molecular weight thiols were able to restore the caspase-inhibitory properties of z-VAD-FMK in activated T cells where caspase-8 and caspase-3 remain activated and processed into their respective subunits in the presence of the caspase inhibitor. This suggests that the inhibition of T cell proliferation can be uncoupled from the caspase-inhibitory properties of z-VAD-FMK. Taken together, the immunosuppressive effects in primary T cells mediated by z-VAD-FMK are due to oxidative stress via the depletion of GSH

  11. T-lymphoblastic leukemia/lymphoma in macedonian patients with Nijmegen breakage syndrome

    Directory of Open Access Journals (Sweden)

    Kocheva SA

    2016-06-01

    Full Text Available Nijmegen breakage syndrome (NBS is a rare autosomal recessive chromosomal instability disorder characterized by microcephaly, immunodeficiency, radiosensitivity and a very high predisposition to malignancy. The gene responsible for the disease, NBS1, is located on chromosome 8q21 and encodes a protein called nibrin. After identification of the gene, a truncating 5 bp deletion, 657-661delACAAA, was identified as the disease-causing mutation in patients with the NBS. In this report, we describe two patients with NBS and T-lymphoblastic leukemia/lymphoma in a Macedonian family. To the best of our knowledge, this is the first family with NBS reported from Macedonia. Both children presented with microcephaly, syndactyly and the development of T cell lymphoblastic lekemia/lymphoma at the age of 7 and 10 years, respectively. The molecular analysis of NBS1 genes in our patients showed homozygosity for the 657del5 mutation in the NBS1 gene. The parents were heterozygotes for the 657del5 mutation and they had no knowledge of a consanguineous relationship. The first child was treated with the International Berlin-Frankfurt-Münster (BFM-Non Hodgkin lymphoma (NHL protocol and achieved a complete remission that lasted for 21 months. Subsequently, he developed a medullar relapse with hyperleukocytosis and died due to lethal central nervous system (CNS complications. The second child was treated according to the International Collaborative Treatment Protocol for Children and Adolescents with Acute Lymphoblastic Leukemia 2009 (AIOP-BFM ALL 2009 protocol. Unfortunately, remission was not achieved.

  12. T-lymphoblastic leukemia/lymphoma in macedonian patients with Nijmegen breakage syndrome.

    Science.gov (United States)

    Kocheva, S A; Martinova, K; Antevska-Trajkova, Z; Coneska-Jovanova, B; Eftimov, A; Dimovski, A J

    2016-07-01

    Nijmegen breakage syndrome (NBS) is a rare autosomal recessive chromosomal instability disorder characterized by microcephaly, immunodeficiency, radiosensitivity and a very high predisposition to malignancy. The gene responsible for the disease, NBS1 , is located on chromosome 8q21 and encodes a protein called nibrin. After identification of the gene, a truncating 5 bp deletion, 657-661delACAAA, was identified as the disease-causing mutation in patients with the NBS. In this report, we describe two patients with NBS and T-lymphoblastic leukemia/lymphoma in a Macedonian family. To the best of our knowledge, this is the first family with NBS reported from Macedonia. Both children presented with microcephaly, syndactyly and the development of T cell lymphoblastic lekemia/lymphoma at the age of 7 and 10 years, respectively. The molecular analysis of NBS1 genes in our patients showed homozygosity for the 657del5 mutation in the NBS1 gene. The parents were heterozygotes for the 657del5 mutation and they had no knowledge of a consanguineous relationship. The first child was treated with the International Berlin-Frankfurt-Münster (BFM)-Non Hodgkin lymphoma (NHL) protocol and achieved a complete remission that lasted for 21 months. Subsequently, he developed a medullar relapse with hyperleukocytosis and died due to lethal central nervous system (CNS) complications. The second child was treated according to the International Collaborative Treatment Protocol for Children and Adolescents with Acute Lymphoblastic Leukemia 2009 (AIOP-BFM ALL 2009) protocol. Unfortunately, remission was not achieved.

  13. Id1 expression promotes peripheral CD4{sup +} T cell proliferation and survival upon TCR activation without co-stimulation

    Energy Technology Data Exchange (ETDEWEB)

    Liu, Chen; Jin, Rong [Department of Immunology, Peking University Health Science Center, Beijing (China); Wang, Hong-Cheng [Oklahoma Medical Research Foundation, Oklahoma City, OK (United States); Tang, Hui; Liu, Yuan-Feng; Qian, Xiao-Ping; Sun, Xiu-Yuan; Ge, Qing [Department of Immunology, Peking University Health Science Center, Beijing (China); Sun, Xiao-Hong, E-mail: sunx@omrf.org [Oklahoma Medical Research Foundation, Oklahoma City, OK (United States); Zhang, Yu, E-mail: zhangyu007@bjmu.edu.cn [Department of Immunology, Peking University Health Science Center, Beijing (China)

    2013-06-21

    Highlights: •Id1 expression enables naïve T cell proliferation without anti-CD28 co-stimulation. •Id1 expression facilitates T cells survival when stimulated with anti-CD3. •Elevation of IL-2 production by Id1 contributes increased proliferation and survival. •Id1 potentiates NF-κB activation by anti-CD3 stimulation. -- Abstract: Although the role of E proteins in the thymocyte development is well documented, much less is known about their function in peripheral T cells. Here we demonstrated that CD4 promoter-driven transgenic expression of Id1, a naturally occurring dominant-negative inhibitor of E proteins, can substitute for the co-stimulatory signal delivered by CD28 to facilitate the proliferation and survival of naïve CD4{sup +} cells upon anti-CD3 stimulation. We next discovered that IL-2 production and NF-κB activity after anti-CD3 stimulation were significantly elevated in Id1-expressing cells, which may be, at least in part, responsible for the augmentation of their proliferation and survival. Taken together, results from this study suggest an important role of E and Id proteins in peripheral T cell activation. The ability of Id proteins to by-pass co-stimulatory signals to enable T cell activation has significant implications in regulating T cell immunity.

  14. New development in CAR-T cell therapy.

    Science.gov (United States)

    Wang, Zhenguang; Wu, Zhiqiang; Liu, Yang; Han, Weidong

    2017-02-21

    Chimeric antigen receptor (CAR)-engineered T cells (CAR-T cells) have yielded unprecedented efficacy in B cell malignancies, most remarkably in anti-CD19 CAR-T cells for B cell acute lymphoblastic leukemia (B-ALL) with up to a 90% complete remission rate. However, tumor antigen escape has emerged as a main challenge for the long-term disease control of this promising immunotherapy in B cell malignancies. In addition, this success has encountered significant hurdles in translation to solid tumors, and the safety of the on-target/off-tumor recognition of normal tissues is one of the main reasons. In this mini-review, we characterize some of the mechanisms for antigen loss relapse and new strategies to address this issue. In addition, we discuss some novel CAR designs that are being considered to enhance the safety of CAR-T cell therapy in solid tumors.

  15. New development in CAR-T cell therapy

    Directory of Open Access Journals (Sweden)

    Zhenguang Wang

    2017-02-01

    Full Text Available Abstract Chimeric antigen receptor (CAR-engineered T cells (CAR-T cells have yielded unprecedented efficacy in B cell malignancies, most remarkably in anti-CD19 CAR-T cells for B cell acute lymphoblastic leukemia (B-ALL with up to a 90% complete remission rate. However, tumor antigen escape has emerged as a main challenge for the long-term disease control of this promising immunotherapy in B cell malignancies. In addition, this success has encountered significant hurdles in translation to solid tumors, and the safety of the on-target/off-tumor recognition of normal tissues is one of the main reasons. In this mini-review, we characterize some of the mechanisms for antigen loss relapse and new strategies to address this issue. In addition, we discuss some novel CAR designs that are being considered to enhance the safety of CAR-T cell therapy in solid tumors.

  16. CD19 CAR-targeted T cells induce long-term remission and B Cell Aplasia in an immunocompetent mouse model of B cell acute lymphoblastic leukemia.

    Directory of Open Access Journals (Sweden)

    Marco L Davila

    Full Text Available Although many adults with B cell acute lymphoblastic leukemia (B-ALL are induced into remission, most will relapse, underscoring the dire need for novel therapies for this disease. We developed murine CD19-specific chimeric antigen receptors (CARs and an immunocompetent mouse model of B-ALL that recapitulates the disease at genetic, cellular, and pathologic levels. Mouse T cells transduced with an all-murine CD3ζ/CD28-based CAR that is equivalent to the one being used in our clinical trials, eradicate B-ALL in mice and mediate long-term B cell aplasias. In this model, we find that increasing conditioning chemotherapy increases tumor eradication, B cell aplasia, and CAR-modified T cell persistence. Quantification of recipient B lineage cells allowed us to estimate an in vivo effector to endogenous target ratio for B cell aplasia maintenance. In mice exhibiting a dramatic B cell reduction we identified a small population of progenitor B cells in the bone marrow that may serve as a reservoir for long-term CAR-modified T cell stimulation. Lastly, we determine that infusion of CD8+ CAR-modified T cells alone is sufficient to maintain long-term B cell eradication. The mouse model we report here should prove valuable for investigating CAR-based and other therapies for adult B-ALL.

  17. A new recurrent inversion, inv(7)(p15q34), leads to transcriptional activation of HOXA10 and HOXA11 in a subset of T-cell acute lymphoblastic leukemias.

    Science.gov (United States)

    Speleman, F; Cauwelier, B; Dastugue, N; Cools, J; Verhasselt, B; Poppe, B; Van Roy, N; Vandesompele, J; Graux, C; Uyttebroeck, A; Boogaerts, M; De Moerloose, B; Benoit, Y; Selleslag, D; Billiet, J; Robert, A; Huguet, F; Vandenberghe, P; De Paepe, A; Marynen, P; Hagemeijer, A

    2005-03-01

    Chromosomal translocations with breakpoints in T-cell receptor (TCR) genes are recurrent in T-cell malignancies. These translocations involve the TCRalphadelta gene (14q11), the TCRbeta gene (7q34) and to a lesser extent the TCRgamma gene at chromosomal band 7p14 and juxtapose T-cell oncogenes next to TCR regulatory sequences leading to deregulated expression of those oncogenes. Here, we describe a new recurrent chromosomal inversion of chromosome 7, inv(7)(p15q34), in a subset of patients with T-cell acute lymphoblastic leukemia characterized by CD2 negative and CD4 positive, CD8 negative blasts. This rearrangement juxtaposes the distal part of the HOXA gene cluster on 7p15 to the TCRbeta locus on 7q34. Real time quantitative PCR analysis for all HOXA genes revealed high levels of HOXA10 and HOXA11 expression in all inv(7) positive cases. This is the first report of a recurrent chromosome rearrangement targeting the HOXA gene cluster in T-cell malignancies resulting in deregulated HOXA gene expression (particularly HOXA10 and HOXA11) and is in keeping with a previous report suggesting HOXA deregulation in MLL-rearranged T- and B cell lymphoblastic leukemia as the key factor in leukaemic transformation. Finally, our observation also supports the previous suggested role of HOXA10 and HOXA11 in normal thymocyte development.

  18. MLL duplication in a pediatric patient with B-cell lymphoblastic lymphoma.

    Science.gov (United States)

    Mater, David Van; Goodman, Barbara K; Wang, Endi; Gaca, Ana M; Wechsler, Daniel S

    2012-04-01

    Lymphoblastic lymphoma is the second most common type of non-Hodgkin lymphoma seen in children. Approximately, 90% of lymphoblastic lymphomas arise from T cells, with the remaining 10% being B-cell-lineage derived. Although T-cell lymphoblastic lymphoma most frequently occurs in the anterior mediastinum (thymus), B-cell lymphoblastic lymphoma (B-LBL) predominates in extranodal sites such as skin and bone. Here, we describe a pediatric B-LBL patient who presented with extensive abdominal involvement and whose lymphoma cells displayed segmental duplication of the mixed lineage leukemia (MLL) gene. MLL duplication/amplification has been described primarily in acute myeloid leukemia and myelodysplastic syndrome with no published reports of discrete MLL duplication/amplification events in B-LBL. The MLL gene duplication noted in this case may represent a novel mechanism for tumorigenesis in B-LBL.

  19. Adipose-derived stem cells were impaired in restricting CD4+T cell proliferation and polarization in type 2 diabetic ApoE-/- mouse.

    Science.gov (United States)

    Liu, Ming-Hao; Li, Ya; Han, Lu; Zhang, Yao-Yuan; Wang, Di; Wang, Zhi-Hao; Zhou, Hui-Min; Song, Ming; Li, Yi-Hui; Tang, Meng-Xiong; Zhang, Wei; Zhong, Ming

    2017-07-01

    Atherosclerosis (AS) is the most common and serious complication of type 2 diabetes mellitus (T2DM) and is accelerated via chronic systemic inflammation rather than hyperglycemia. Adipose tissue is the major source of systemic inflammation in abnormal metabolic state. Pro-inflammatory CD4 + T cells play pivotal role in promoting adipose inflammation. Adipose-derived stem cells (ADSCs) for fat regeneration have potent ability of immunosuppression and restricting CD4 + T cells as well. Whether T2DM ADSCs are impaired in antagonizing CD4 + T cell proliferation and polarization remains unclear. We constructed type 2 diabetic ApoE -/- mouse models and tested infiltration and subgroups of CD4 + T cell in stromal-vascular fraction (SVF) in vivo. Normal/T2DM ADSCs and normal splenocytes with or without CD4 sorting were separated and co-cultured at different scales ex vivo. Immune phenotypes of pro- and anti-inflammation of ADSCs were also investigated. Flow cytometry (FCM) and ELISA were applied in the experiments above. CD4 + T cells performed a more pro-inflammatory phenotype in adipose tissue in T2DM ApoE -/- mice in vivo. Restriction to CD4 + T cell proliferation and polarization was manifested obviously weakened after co-cultured with T2DM ADSCs ex vivo. No obvious distinctions were found in morphology and growth type of both ADSCs. However, T2DM ADSCs acquired a pro-inflammatory immune phenotype, with secreting less PGE2 and expressing higher MHC-II and co-stimulatory molecules (CD40, CD80). Normal ADSCs could also obtain the phenotypic change after cultured with T2DM SVF supernatant. CD4 + T cell infiltration and pro-inflammatory polarization exist in adipose tissue in type 2 diabetic ApoE -/- mice. T2DM ADSCs had impaired function in restricting CD4 + T lymphocyte proliferation and pro-inflammatory polarization due to immune phenotypic changes. Copyright © 2017 Elsevier Ltd. All rights reserved.

  20. Mast cells enhance T cell activation: Importance of mast cell-derived TNF

    Science.gov (United States)

    Nakae, Susumu; Suto, Hajime; Kakurai, Maki; Sedgwick, Jonathon D.; Tsai, Mindy; Galli, Stephen J.

    2005-05-01

    Mast cells are not only important effector cells in immediate hypersensitivity reactions and immune responses to pathogens but also can contribute to T cell-mediated disorders. However, the mechanisms by which mast cells might influence T cells in such settings are not fully understood. We find that mast cells can enhance proliferation and cytokine production in multiple T cell subsets. Mast cell-dependent enhancement of T cell activation can be promoted by FcRI-dependent mast cell activation, TNF production by both mast cells and T cells, and mast cell-T cell contact. However, at high concentrations of cells, mast cells can promote T cell activation independent of IgE or TNF. Finally, mast cells also can promote T cell activation by means of soluble factors. These findings identify multiple mechanisms by which mast cells can influence T cell proliferation and cytokine production. allergy | asthma | autoimmunity | cytokines | immune response

  1. OX40 and IL-7 play synergistic roles in the homeostatic proliferation of effector memory CD4⁺ T cells.

    Science.gov (United States)

    Yamaki, Satoshi; Ine, Shouji; Kawabe, Takeshi; Okuyama, Yuko; Suzuki, Nobu; Soroosh, Pejman; Mousavi, Seyed Fazlollah; Nagashima, Hiroyuki; Sun, Shu-lan; So, Takanori; Sasaki, Takeshi; Harigae, Hideo; Sugamura, Kazuo; Kudo, Hironori; Wada, Motoshi; Nio, Masaki; Ishii, Naoto

    2014-10-01

    T-cell homeostasis preserves the numbers, the diversity and functional competence of different T-cell subsets that are required for adaptive immunity. Naïve CD4(+) T (TN ) cells are maintained in the periphery via the common γ-chain family cytokine IL-7 and weak antigenic signals. However, it is not clear how memory CD4(+) T-cell subsets are maintained in the periphery and which factors are responsible for the maintenance. To examine the homeostatic mechanisms, CFSE-labeled CD4(+) CD44(high) CD62L(low) effector memory T (TEM ) cells were transferred into sublethally-irradiated syngeneic C57BL/6 mice, and the systemic cell proliferative responses, which can be divided distinctively into fast and slow proliferations, were assessed by CFSE dye dilution. We found that the fast homeostatic proliferation of TEM cells was strictly regulated by both antigen and OX40 costimulatory signals and that the slow proliferation was dependent on IL-7. The simultaneous blockade of both OX40 and IL-7 signaling completely inhibited the both fast and slow proliferation. The antigen- and OX40-dependent fast proliferation preferentially expanded IL-17-producing helper T cells (Th17 cells). Thus, OX40 and IL-7 play synergistic, but distinct roles in the homeostatic proliferation of CD4(+) TEM cells. © 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  2. Inhibition of T cell proliferation by selective block of Ca(2+)-activated K(+) channels

    DEFF Research Database (Denmark)

    Jensen, B S; Odum, Niels; Jorgensen, N K

    1999-01-01

    cell activation and proliferation has been investigated by using various blockers of IK channels. The Ca(2+)-activated K(+) current in human T cells is shown by the whole-cell voltage-clamp technique to be highly sensitive to clotrimazole, charybdotoxin, and nitrendipine, but not to ketoconazole...

  3. Immunoregulatory T cells in man. Histamine-induced suppressor T cells are derived from a Leu 2+ (T8+) subpopulation distinct from that which gives rise to cytotoxic T cells

    International Nuclear Information System (INIS)

    Sansoni, P.; Silverman, E.D.; Khan, M.M.; Melmon, K.L.; Engleman, E.G.

    1985-01-01

    One mechanism of histamine-mediated inhibition of the immune response in man is to activate T suppressor cells that bear the Leu 2 (OKT8) marker. The current study was undertaken to characterize the histamine-induced suppressor cell using a monoclonal antibody (9.3) shown previously to distinguish cytotoxic T cells from antigen-specific suppressor T cells. Leu 2+ cells isolated from peripheral blood were further separated with antibody 9.3 into Leu 2+, 9.3+, and Leu 2+, 9.3- subsets and each subset was incubated with different concentrations of histamine before determining their ability to suppress immune responses in vitro. The results indicate that the Leu 2+, 9.3- subpopulation includes all histamine-induced suppressor cells, that 10(-4) M histamine is the optimal concentration for suppressor cell induction, and that exposure of Leu 2+, 9.3- cells to histamine for 30 s is sufficient to initiate the induction process. After treatment with histamine these cells inhibit both phytohemagglutinin-induced T cell proliferation and pokeweed mitogen-induced B cell differentiation. The suppression of phytohemagglutinin-induced proliferation was resistant to x-irradiation with 1,200 rad, either before or after histamine exposure, suggesting that Leu 2+, 9.3- cells need not proliferate to become suppressor cells or exert suppression. Moreover, suppression by these cells was not due to altered kinetics of the response. Finally, a histamine type 2 receptor antagonist (cimetidine) but not a type 1 receptor antagonist (mepyramine) blocked the induction of suppressor cells. On the basis of these results and our previous studies of antigen specific suppressor cells, we conclude that Leu 2+ suppressor cells in man are derived from a precursor pool that is phenotypically distinct from cells that can differentiate into cytotoxic T cells

  4. Antigen-driven T-cell turnover

    NARCIS (Netherlands)

    Fraser, Christophe; Ferguson, Neil M.; de Wolf, Frank; Ghani, Azra C.; Garnett, Geoff P.; Anderson, Roy M.

    2002-01-01

    A mathematical model is developed to characterize the distribution of cell turnover rates within a population of T lymphocytes. Previous models of T-cell dynamics have assumed a constant uniform turnover rate; here we consider turnover in a cell pool subject to clonal proliferation in response to

  5. DNA Methylation Adds Prognostic Value to Minimal Residual Disease Status in Pediatric T-Cell Acute Lymphoblastic Leukemia.

    Science.gov (United States)

    Borssén, Magnus; Haider, Zahra; Landfors, Mattias; Norén-Nyström, Ulrika; Schmiegelow, Kjeld; Åsberg, Ann E; Kanerva, Jukka; Madsen, Hans O; Marquart, Hanne; Heyman, Mats; Hultdin, Magnus; Roos, Göran; Forestier, Erik; Degerman, Sofie

    2016-07-01

    Despite increased knowledge about genetic aberrations in pediatric T-cell acute lymphoblastic leukemia (T-ALL), no clinically feasible treatment-stratifying marker exists at diagnosis. Instead patients are enrolled in intensive induction therapies with substantial side effects. In modern protocols, therapy response is monitored by minimal residual disease (MRD) analysis and used for postinduction risk group stratification. DNA methylation profiling is a candidate for subtype discrimination at diagnosis and we investigated its role as a prognostic marker in pediatric T-ALL. Sixty-five diagnostic T-ALL samples from Nordic pediatric patients treated according to the Nordic Society of Pediatric Hematology and Oncology ALL 2008 (NOPHO ALL 2008) protocol were analyzed by HumMeth450K genome wide DNA methylation arrays. Methylation status was analyzed in relation to clinical data and early T-cell precursor (ETP) phenotype. Two distinct CpG island methylator phenotype (CIMP) groups were identified. Patients with a CIMP-negative profile had an inferior response to treatment compared to CIMP-positive patients (3-year cumulative incidence of relapse (CIR3y ) rate: 29% vs. 6%, P = 0.01). Most importantly, CIMP classification at diagnosis allowed subgrouping of high-risk T-ALL patients (MRD ≥0.1% at day 29) into two groups with significant differences in outcome (CIR3y rates: CIMP negative 50% vs. CIMP positive 12%; P = 0.02). These groups did not differ regarding ETP phenotype, but the CIMP-negative group was younger (P = 0.02) and had higher white blood cell count at diagnosis (P = 0.004) compared with the CIMP-positive group. CIMP classification at diagnosis in combination with MRD during induction therapy is a strong candidate for further risk classification and could confer important information in treatment decision making. © 2016 Wiley Periodicals, Inc.

  6. Neuron-mediated generation of regulatory T cells from encephalitogenic T cells suppresses EAE

    DEFF Research Database (Denmark)

    Liu, Yawei; Teige, Ingrid; Birnir, Bryndis

    2006-01-01

    Neurons have been neglected as cells with a major immune-regulatory function because they do not express major histocompatibility complex class II. Our data show that neurons are highly immune regulatory, having a crucial role in governing T-cell response and central nervous system (CNS) inflamma......Neurons have been neglected as cells with a major immune-regulatory function because they do not express major histocompatibility complex class II. Our data show that neurons are highly immune regulatory, having a crucial role in governing T-cell response and central nervous system (CNS......) inflammation. Neurons induce the proliferation of activated CD4+ T cells through B7-CD28 and transforming growth factor (TGF)-beta1-TGF-beta receptor signaling pathways, resulting in amplification of T-cell receptor signaling through phosphorylated ZAP-70, interleukin (IL)-2 and IL-9. The interaction between...... neurons and T cells results in the conversion of encephalitogenic T cells to CD25+ TGF-beta1+ CTLA-4+ FoxP3+ T regulatory (Treg) cells that suppress encephalitogenic T cells and inhibit experimental autoimmune encephalomyelitis. Suppression is dependent on cytotoxic T lymphocyte antigen (CTLA)-4...

  7. Induction of a central memory and stem cell memory phenotype in functionally active CD4+ and CD8+ CAR T cells produced in an automated good manufacturing practice system for the treatment of CD19+ acute lymphoblastic leukemia.

    Science.gov (United States)

    Blaeschke, Franziska; Stenger, Dana; Kaeuferle, Theresa; Willier, Semjon; Lotfi, Ramin; Kaiser, Andrew Didier; Assenmacher, Mario; Döring, Michaela; Feucht, Judith; Feuchtinger, Tobias

    2018-03-31

    Relapsed/refractory B-precursor acute lymphoblastic leukemia (pre-B ALL) remains a major therapeutic challenge. Chimeric antigen receptor (CAR) T cells are promising treatment options. Central memory T cells (Tcm) and stem cell-like memory T cells (Tscm) are known to promote sustained proliferation and persistence after T-cell therapy, constituting essential preconditions for treatment efficacy. Therefore, we set up a protocol for anti-CD19 CAR T-cell generation aiming at high Tcm/Tscm numbers. 100 ml peripheral blood from pediatric pre-B ALL patients was processed including CD4 + /CD8 + -separation, T-cell activation with modified anti-CD3/-CD28 reagents and transduction with a 4-1BB-based second generation CAR lentiviral vector. The process was performed on a closed, automated device requiring additional manual/open steps under clean room conditions. The clinical situation of these critically ill and refractory patients with leukemia leads to inconsistent cellular compositions at start of the procedure including high blast counts and low T-cell numbers with exhausted phenotype. Nevertheless, a robust T-cell product was achieved (mean CD4 +  = 50%, CD8 +  = 39%, transduction = 27%, Tcm = 50%, Tscm = 46%). Strong proliferative potential (up to > 100-fold), specific cytotoxicity and low expression of co-inhibitory molecules were documented. CAR T cells significantly released TH1 cytokines IFN-γ, TNF-α and IL-2 upon target-recognition. In conclusion, partly automated GMP-generation of CAR T cells from critically small blood samples was feasible with a new stimulation protocol that leads to high functionality and expansion potential, balanced CD4/CD8 ratios and a conversion to a Tcm/Tscm phenotype.

  8. Functioning of spontaneous and induced Con A regulators of T-cell proliferation. Modifying factors

    International Nuclear Information System (INIS)

    Kuz'mina, E.G.

    1989-01-01

    It is shown that active spontaneous non-specific regulators of T-cell proliferation are activated in peripheral blood ''in vivo'' by endogenous metabolites; non-specific regulator action can be induced ''in vitro'' by Con A, FGA. Non-specific regulators suppress and increase lymphocyte proliferation. Cyclic character of their functioning is revealed. 4 refs.; 1 tab

  9. Murine neonatal spleen contains natural T and non-T suppressor cells capable of inhibiting adult alloreactive and newborn autoreactive T-cell proliferation.

    Science.gov (United States)

    Hooper, D C; Hoskin, D W; Gronvik, K O; Murgita, R A

    1986-05-01

    The spleen of neonatal mice is known to be a rich source of cells capable of suppressing a variety of immune functions of adult lymphocytes in vitro. From such observations has emerged the concept that the gradual development in ability to express immune functions after birth is due in part to the parallel normal physiological decay of naturally occurring regulatory suppressor cells. There is, however, some confusion in the literature as to the exact nature of the newborn of the newborn inhibitory cell type(s). In contrast to most previous reports which detect only a single type of neonatal suppressor cell, usually a T cell, we show here that newborn spleen harbors both T and non-T inhibitory cells. Both types of suppressor cells could be shown to suppress the proliferative response of adult spleen to alloantigens as well as newborn T cells reacting against self-Ia antigen in the autologous mixed lymphocyte reaction (AMLR). Newborn suppressor T cells were characterized as being non-adherent to Ig-anti-Ig affinity columns, soybean agglutinin receptor negative (SBA-), and susceptible to lysis by anti-T-cell specific antiserum plus complement. Non-T suppressor cells were identified as non-phagocytic, SBA receptor positive (SBA+), and resistant to cytotoxic treatment with anti-T-cell antibodies and complement. The apparent controversy surrounding previous reports as to the T versus non-T nature of newborn suppressor cells can be reconciled by the present observation that both types of inhibitory cells coexist in the spleen. Furthermore, the demonstration that newborn suppressor cells can effectively regulate T-cell proliferative activity mediated by other newborn cells provides more direct support for the contention that such inhibitory cells play a physiological role in controlling immune responsiveness during early ontogeny.

  10. Riboflavin Depletion Promotes Tumorigenesis in HEK293T and NIH3T3 Cells by Sustaining Cell Proliferation and Regulating Cell Cycle-Related Gene Transcription.

    Science.gov (United States)

    Long, Lin; He, Jian-Zhong; Chen, Ye; Xu, Xiu-E; Liao, Lian-Di; Xie, Yang-Min; Li, En-Min; Xu, Li-Yan

    2018-05-07

    Riboflavin is an essential component of the human diet and its derivative cofactors play an established role in oxidative metabolism. Riboflavin deficiency has been linked with various human diseases. The objective of this study was to identify whether riboflavin depletion promotes tumorigenesis. HEK293T and NIH3T3 cells were cultured in riboflavin-deficient or riboflavin-sufficient medium and passaged every 48 h. Cells were collected every 5 generations and plate colony formation assays were performed to observe cell proliferation. Subcutaneous tumorigenicity assays in NU/NU mice were used to observe tumorigenicity of riboflavin-depleted HEK293T cells. Mechanistically, gene expression profiling and gene ontology analysis were used to identify abnormally expressed genes induced by riboflavin depletion. Western blot analyses, cell cycle analyses, and chromatin immunoprecipitation were used to validate the expression of cell cycle-related genes. Plate colony formation of NIH3T3 and HEK293T cell lines was enhanced >2-fold when cultured in riboflavin-deficient medium for 10-20 generations. Moreover, we observed enhanced subcutaneous tumorigenicity in NU/NU mice following injection of riboflavin-depleted compared with normal HEK293T cells (55.6% compared with 0.0% tumor formation, respectively). Gene expression profiling and gene ontology analysis revealed that riboflavin depletion induced the expression of cell cycle-related genes. Validation experiments also found that riboflavin depletion decreased p21 and p27 protein levels by ∼20%, and increased cell cycle-related and expression-elevated protein in tumor (CREPT) protein expression >2-fold, resulting in cyclin D1 and CDK4 levels being increased ∼1.5-fold, and cell cycle acceleration. We also observed that riboflavin depletion decreased intracellular riboflavin levels by 20% and upregulated expression of riboflavin transporter genes, particularly SLC52A3, and that the changes in CREPT and SLC52A3 correlated with

  11. Suppression of human T cell proliferation by the caspase inhibitors, z-VAD-FMK and z-IETD-FMK is independent of their caspase inhibition properties

    Energy Technology Data Exchange (ETDEWEB)

    Lawrence, C.P. [Medical Research Council Toxicology Unit, Hodgkin Building, Lancaster Road, University of Leicester, Leicester LE1 9HN (United Kingdom); Chow, S.C., E-mail: chow.sek.chuen@monash.edu [School of Science, Monash University Sunway Campus, Jalan Lagoon Selatan, Bandar Sunway, 46150 Selangor Darul Ehsan (Malaysia)

    2012-11-15

    The caspase inhibitors, benzyloxycarbony (Cbz)-l-Val-Ala-Asp (OMe)-fluoromethylketone (z-VAD-FMK) and benzyloxycarbonyl (Cbz)-Ile-Glu (OMe)-Thr-Asp (OMe)-FMK (z-IETD-FMK) at non-toxic doses were found to be immunosuppressive and inhibit human T cell proliferation induced by mitogens and IL-2 in vitro. Both caspase inhibitors were shown to block NF-κB in activated primary T cells, but have little inhibitory effect on the secretion of IL-2 and IFN-γ during T cell activation. However, the expression of IL-2 receptor α-chain (CD25) in activated T cells was inhibited by both z-VAD-FMK and z-IETD-FMK, whereas the expression of the early activated T cell marker, CD69 was unaffected. During primary T cell activation via the antigen receptor, both caspase-8 and caspase-3 were activated and processed to their respective subunits, but neither caspase inhibitors had any effect on the processing of these two caspases. In sharp contrast both caspase inhibitors readily blocked apoptosis and the activation of caspases during FasL-induced apoptosis in activated primary T cells and Jurkat T cells. Collectively, the results demonstrate that both z-VAD-FMK and z-IETD-FMK are immunosuppressive in vitro and inhibit T cell proliferation without blocking the processing of caspase-8 and caspase-3. -- Highlights: ► Caspase-8 and caspase-3 were activated during T cell activation and proliferation. ► T cell proliferation was blocked by caspase inhibitors. ► Caspase activation during T cell proliferation was not block by caspase inhibitors.

  12. STAT3 Regulates Proliferation and Survival of CD8+ T Cells: Enhances Effector Responses to HSV-1 Infection, and Inhibits IL-10+ Regulatory CD8+ T Cells in Autoimmune Uveitis

    Directory of Open Access Journals (Sweden)

    Cheng-Rong Yu

    2013-01-01

    Full Text Available STAT3 regulates CD4+ T cell survival and differentiation. However, its effects on CD8+ T cells are not well understood. Here, we show that in comparison to WT CD8+ T cells, STAT3-deficient CD8+ T cells exhibit a preactivated memory-like phenotype, produce more IL-2, proliferate faster, and are more sensitive to activation-induced cell death (AICD. The enhanced proliferation and sensitivity to AICD correlated with downregulation of class-O forkhead transcription factors (FoxO1, FoxO3A, , , Bcl-2, OX-40, and upregulation of FasL, Bax, and Bad. We examined whether STAT3-deficient CD8+ T cells can mount effective response during herpes simplex virus (HSV-1 infection and experimental autoimmune uveitis (EAU. Compared to WT mice, HSV-1-infected STAT3-deficient mice (STAT3KO produced less IFN- and virus-specific KLRG-1+ CD8+ T cells. STAT3KO mice are also resistant to EAU and produced less IL-17-producing Tc17 cells. Resistance of STAT3KO to EAU correlated with marked expansion of IL-10-producing regulatory CD8+ T cells (CD8-Treg implicated in recovery from autoimmune encephalomyelitis. Thus, increases of IL-6-induced STAT3 activation observed during inflammation may inhibit expansion of CD8-Tregs, thereby impeding recovery from uveitis. These results suggest that STAT3 is a potential therapeutic target for upregulating CD8+ T cell-mediated responses to viruses and suggest the successful therapeutic targeting of STAT3 as treatment for uveitis, derived, in part, from promoting CD8-Treg expansion.

  13. Long-lasting inhibitory effects of fetal liver mesenchymal stem cells on T-lymphocyte proliferation.

    Directory of Open Access Journals (Sweden)

    Massimo Giuliani

    Full Text Available Human bone marrow mesenchymal stem cells (BM-MSC are multipotent progenitor cells that have transient immunomodulatory properties on Natural Killer (NK cells, Dendritic Cells (DC, and T cells. This study compared the use of MSC isolated from bone marrow and fetal liver (FL-MSC to determine which displayed the most efficient immunosuppressive effects on T cell activation. Although both types of MSC exhibit similar phenotype profile, FL-MSC displays a much more extended in vitro life-span and immunomodulatory properties. When co-cultured with CD3/CD28-stimulated T cells, both BM-MSC and FL-MSC affected T cell proliferation by inhibiting their entry into the cell cycle, by inducing the down-regulation of phospho-retinoblastoma (pRb, cyclins A and D1, as well as up-regulating p27(kip1 expression. The T cell inhibition by MSC was not due to the soluble HLA-G5 isoform, but to the surface expression of HLA-G1, as shown by the need of cell-cell contact and by the use of neutralizing anti-HLA-G antibodies. To note, in a HLA-G-mediated fashion, MSC facilitated the expansion of a CD4(low/CD8(low T subset that had decreased secretion of IFN-γ, and an induced secretion of the immunomodulatory cytokine IL-10. Because of their longer lasting in vitro immunosuppressive properties, mainly mediated by HLA-G, and their more efficient induction of IL-10 production and T cell apoptosis, fetal liver MSC could be considered a new tool for MSC therapy to prevent allograft rejection.

  14. Memory phenotype CD4 T cells undergoing rapid, nonburst-like, cytokine-driven proliferation can be distinguished from antigen-experienced memory cells.

    Directory of Open Access Journals (Sweden)

    Souheil-Antoine Younes

    2011-10-01

    Full Text Available Memory phenotype (CD44(bright, CD25(negative CD4 spleen and lymph node T cells (MP cells proliferate rapidly in normal or germ-free donors, with BrdU uptake rates of 6% to 10% per day and Ki-67 positivity of 18% to 35%. The rapid proliferation of MP cells stands in contrast to the much slower proliferation of lymphocytic choriomeningitis virus (LCMV-specific memory cells that divide at rates ranging from <1% to 2% per day over the period from 15 to 60 days after LCMV infection. Anti-MHC class II antibodies fail to inhibit the in situ proliferation of MP cells, implying a non-T-cell receptor (TCR-driven proliferation. Such proliferation is partially inhibited by anti-IL-7Rα antibody. The sequence diversity of TCRβ CDR3 gene segments is comparable among the proliferating and quiescent MP cells from conventional and germ-free mice, implying that the majority of proliferating MP cells have not recently derived from a small cohort of cells that expand through multiple continuous rounds of cell division. We propose that MP cells constitute a diverse cell population, containing a subpopulation of slowly dividing authentic antigen-primed memory cells and a majority population of rapidly proliferating cells that did not arise from naïve cells through conventional antigen-driven clonal expansion.

  15. Caspase-1 from Human Myeloid-Derived Suppressor Cells Can Promote T Cell-Independent Tumor Proliferation.

    Science.gov (United States)

    Zeng, Qi; Fu, Juan; Korrer, Michael; Gorbounov, Mikhail; Murray, Peter J; Pardoll, Drew; Masica, David L; Kim, Young J

    2018-05-01

    Immunosuppressive myeloid-derived suppressive cells (MDSCs) are characterized by their phenotypic and functional heterogeneity. To better define their T cell-independent functions within the tumor, sorted monocytic CD14 + CD11b + HLA-DR low/- MDSCs (mMDSC) from squamous cell carcinoma patients showed upregulated caspase-1 activity, which was associated with increased IL1β and IL18 expression. In vitro studies demonstrated that mMDSCs promoted caspase-1-dependent proliferation of multiple squamous carcinoma cell lines in both human and murine systems. In vivo , growth rates of B16, MOC1, and Panc02 were significantly blunted in chimeric mice adoptively transferred with caspase-1 null bone marrow cells under T cell-depleted conditions. Adoptive transfer of wild-type Gr-1 + CD11b + MDSCs from tumor-bearing mice reversed this antitumor response, whereas caspase-1 inhibiting thalidomide-treated MDSCs phenocopied the antitumor response found in caspase-1 null mice. We further hypothesized that MDSC caspase-1 activity could promote tumor-intrinsic MyD88-dependent carcinogenesis. In mice with wild-type caspase-1, MyD88-silenced tumors displayed reduced growth rate, but in chimeric mice with caspase-1 null bone marrow cells, MyD88-silenced tumors did not display differential tumor growth rate. When we queried the TCGA database, we found that caspase-1 expression is correlated with overall survival in squamous cell carcinoma patients. Taken together, our findings demonstrated that caspase-1 in MDSCs is a direct T cell-independent mediator of tumor proliferation. Cancer Immunol Res; 6(5); 566-77. ©2018 AACR . ©2018 American Association for Cancer Research.

  16. Rapamycin sensitizes T-ALL cells to dexamethasone-induced apoptosis

    Directory of Open Access Journals (Sweden)

    Mu Dezhi

    2010-11-01

    Full Text Available Abstract Background Glucocorticoid (GC resistance is frequently seen in acute lymphoblastic leukemia of T-cell lineage (T-ALL. In this study we investigate the potential and mechanism of using rapamycin to restore the sensitivity of GC-resistant T-ALL cells to dexamethasone (Dex treatment. Methods Cell proliferation was detected by 3-(4,5-dimethylthiazol-2-yl- 2,5-diphenyltetrazolium bromide (MTT assay. Fluorescence-activated cell sorting (FACS analysis was used to analyze apoptosis and cell cycles. Western blot analysis was performed to test the expression of the downstream effector proteins of mammalian target of rapamycin (mTOR, the cell cycle regulatory proteins, and apoptosis associated proteins. Results 10 nM rapamycin markedly increased GC sensitivity in GC-resistant T-ALL cells and this effect was mediated, at least in part, by inhibition of mTOR signaling pathway. Cell cycle arrest was associated with modulation of G1-S phase regulators. Both rapamycin and Dex can induce up-regulation of cyclin-dependent kinase (CDK inhibitors of p21 and p27 and co-treatment of rapamycin with Dex resulted in a synergistic induction of their expressions. Rapamycin did not obviously affect the expression of cyclin A, whereas Dex induced cyclin A expression. Rapamycin prevented Dex-induced expression of cyclin A. Rapamycin had a stronger inhibition of cyclin D1 expression than Dex. Rapamycin enhanced GC-induced apoptosis and this was not achieved by modulation of glucocorticoid receptor (GR expression, but synergistically up-regulation of pro-apoptotic proteins like caspase-3, Bax, and Bim, and down-regulation of anti-apoptotic protein of Mcl-1. Conclusion Our data suggests that rapamycin can effectively reverse GC resistance in T-ALL and this effect is achieved by inducing cell cycles arrested at G0/G1 phase and activating the intrinsic apoptotic program. Therefore, combination of mTOR inhibitor rapamycin with GC containing protocol might be an attracting

  17. C22:0- and C24:0-dihydroceramides confer mixed cytotoxicity in T-cell acute lymphoblastic leukemia cell lines.

    Directory of Open Access Journals (Sweden)

    Michael W Holliday

    Full Text Available We previously reported that fenretinide (4-HPR was cytotoxic to acute lymphoblastic leukemia (ALL cell lines in vitro in association with increased levels of de novo synthesized dihydroceramides, the immediate precursors of ceramides. However, the cytotoxic potentials of native dihydroceramides have not been defined. Therefore, we determined the cytotoxic effects of increasing dihydroceramide levels via de novo synthesis in T-cell ALL cell lines and whether such cytotoxicity was dependent on an absolute increase in total dihydroceramide mass versus an increase of certain specific dihydroceramides. A novel method employing supplementation of individual fatty acids, sphinganine, and the dihydroceramide desaturase-1 (DES inhibitor, GT-11, was used to increase de novo dihydroceramide synthesis and absolute levels of specific dihydroceramides and ceramides. Sphingolipidomic analyses of four T-cell ALL cell lines revealed strong positive correlations between cytotoxicity and levels of C22:0-dihydroceramide (ρ = 0.74-0.81, P ≤ 0.04 and C24:0-dihydroceramide (ρ = 0.84-0.90, P ≤ 0.004, but not between total or other individual dihydroceramides, ceramides, or sphingoid bases or phosphorylated derivatives. Selective increase of C22:0- and C24:0-dihydroceramide increased level and flux of autophagy marker, LC3B-II, and increased DNA fragmentation (TUNEL assay in the absence of an increase of reactive oxygen species; pan-caspase inhibition blocked DNA fragmentation but not cell death. C22:0-fatty acid supplemented to 4-HPR treated cells further increased C22:0-dihydroceramide levels (P ≤ 0.001 and cytotoxicity (P ≤ 0.001. These data demonstrate that increases of specific dihydroceramides are cytotoxic to T-cell ALL cells by a caspase-independent, mixed cell death mechanism associated with increased autophagy and suggest that dihydroceramides may contribute to 4-HPR-induced cytotoxicity. The targeted increase of specific acyl chain dihydroceramides

  18. L-type amino-acid transporter 1 (LAT1): a therapeutic target supporting growth and survival of T-cell lymphoblastic lymphoma/T-cell acute lymphoblastic leukemia

    NARCIS (Netherlands)

    Rosilio, C.; Nebout, M.; Imbert, V.; Griessinger, E.; Neffati, Z.; Benadiba, J.; Hagenbeek, T.; Spits, H.; Reverso, J.; Ambrosetti, D.; Michiels, J.-F.; Bailly-Maitre, B.; Endou, H.; Wempe, M. F.; Peyron, J.-F.

    2015-01-01

    The altered metabolism of cancer cells is a treasure trove to discover new antitumoral strategies. The gene (SLC7A5) encoding system L amino-acid transporter 1 (LAT1) is overexpressed in murine lymphoma cells generated via T-cell deletion of the pten tumor suppressor, and also in human T-cell acute

  19. Galectin-7 promotes proliferation and Th1/2 cells polarization toward Th1 in activated CD4+ T cells by inhibiting The TGFβ/Smad3 pathway.

    Science.gov (United States)

    Luo, Zhenlong; Ji, Yudong; Tian, Dean; Zhang, Yong; Chang, Sheng; Yang, Chao; Zhou, Hongmin; Chen, Zhonghua Klaus

    2018-06-08

    Galectin-7 (Gal-7) has been associated with cell proliferation and apoptosis. It is known that Gal-7 antagonises TGFβ-mediated effects in hepatocytes by interacting with Smad3. Previously, we have demonstrated that Gal-7 is related to CD4+ T cells responses; nevertheless, its effect and functional mechanism on CD4+ T cells responses remain unclear. The murine CD4+ T cells were respectively cultured with Gal-7, anti-CD3/CD28 mAbs, or with anti-CD3/CD28 mAbs & Gal-7. The effects of Gal-7 on proliferation and the phenotypic changes in CD4+ T cells were assessed by flow cytometry. The cytokines from CD4+ T cells were analysed by quantitative real-time PCR. Subcellular localisation and expression of Smad3 were determined by immunofluorescence staining and Western blot, respectively. Gal-7 enhanced the proliferation of activated CD4+ T cells in a dose- and β-galactoside-dependent manner. Additionally, Gal-7 treatment did not change the ratio of Th2 cells in activated CD4+ T cells, while it increased the ratio of Th1 cells. Gal-7 also induced activated CD4+ T cells to produce a higher level of IFN-γ and TNF-α and a lower level of IL-10. Moreover, Gal-7 treatment significantly accelerated nuclear export of Smad3 in activated CD4+ T cells. These results revealed a novel role of Gal-7 in promoting proliferation and Th1/2 cells polarization toward Th1 in activated CD4+ T cells by inhibiting the TGFβ/Smad3 pathway. Copyright © 2018 Elsevier Ltd. All rights reserved.

  20. Chimeric antigen receptor T cell (CAR-T) immunotherapy for solid tumors: lessons learned and strategies for moving forward.

    Science.gov (United States)

    Li, Jian; Li, Wenwen; Huang, Kejia; Zhang, Yang; Kupfer, Gary; Zhao, Qi

    2018-02-13

    Recently, the US Food and Drug Administration (FDA) approved the first chimeric antigen receptor T cell (CAR-T) therapy for the treatment CD19-positive B cell acute lymphoblastic leukemia. While CAR-T has achieved remarkable success in the treatment of hematopoietic malignancies, whether it can benefit solid tumor patients to the same extent is still uncertain. Even though hundreds of clinical trials are undergoing exploring a variety of tumor-associated antigens (TAA), no such antigen with comparable properties like CD19 has yet been identified regarding solid tumors CAR-T immunotherapy. Inefficient T cell trafficking, immunosuppressive tumor microenvironment, suboptimal antigen recognition specificity, and lack of safety control are currently considered as the main obstacles in solid tumor CAR-T therapy. Here, we reviewed the solid tumor CAR-T clinical trials, emphasizing the studies with published results. We further discussed the challenges that CAR-T is facing for solid tumor treatment and proposed potential strategies to improve the efficacy of CAR-T as promising immunotherapy.

  1. Merkel Cell Polyomavirus Small T Antigen Induces Cancer and Embryonic Merkel Cell Proliferation in a Transgenic Mouse Model.

    Science.gov (United States)

    Shuda, Masahiro; Guastafierro, Anna; Geng, Xuehui; Shuda, Yoko; Ostrowski, Stephen M; Lukianov, Stefan; Jenkins, Frank J; Honda, Kord; Maricich, Stephen M; Moore, Patrick S; Chang, Yuan

    2015-01-01

    Merkel cell polyomavirus (MCV) causes the majority of human Merkel cell carcinomas (MCC) and encodes a small T (sT) antigen that transforms immortalized rodent fibroblasts in vitro. To develop a mouse model for MCV sT-induced carcinogenesis, we generated transgenic mice with a flox-stop-flox MCV sT sequence homologously recombined at the ROSA locus (ROSAsT), allowing Cre-mediated, conditional MCV sT expression. Standard tamoxifen (TMX) administration to adult UbcCreERT2; ROSAsT mice, in which Cre is ubiquitously expressed, resulted in MCV sT expression in multiple organs that was uniformly lethal within 5 days. Conversely, most adult UbcCreERT2; ROSAsT mice survived low-dose tamoxifen administration but developed ear lobe dermal hyperkeratosis and hypergranulosis. Simultaneous MCV sT expression and conditional homozygous p53 deletion generated multi-focal, poorly-differentiated, highly anaplastic tumors in the spleens and livers of mice after 60 days of TMX treatment. Mouse embryonic fibroblasts from these mice induced to express MCV sT exhibited anchorage-independent cell growth. To examine Merkel cell pathology, MCV sT expression was also induced during mid-embryogenesis in Merkel cells of Atoh1CreERT2/+; ROSAsT mice, which lead to significantly increased Merkel cell numbers in touch domes at late embryonic ages that normalized postnatally. Tamoxifen administration to adult Atoh1CreERT2/+; ROSAsT and Atoh1CreERT2/+; ROSAsT; p53flox/flox mice had no effects on Merkel cell numbers and did not induce tumor formation. Taken together, these results show that MCV sT stimulates progenitor Merkel cell proliferation in embryonic mice and is a bona fide viral oncoprotein that induces full cancer cell transformation in the p53-null setting.

  2. Anti-inflammatory activity of chloroquine and amodiaquine through p21-mediated suppression of T cell proliferation and Th1 cell differentiation

    International Nuclear Information System (INIS)

    Oh, Sera; Shin, Ji Hyun; Jang, Eun Jung; Won, Hee Yeon; Kim, Hyo Kyeong; Jeong, Mi- Gyeong; Kim, Kwang Soo; Hwang, Eun Sook

    2016-01-01

    Chloroquine (CQ) and amodiaquine (AQ) have been used for treating or preventing malaria for decades, and their application has expanded into treating inflammatory disease in humans. CQ and AQ are applicable for controlling rheumatoid arthritis, but their molecular mechanisms of anti-inflammatory activity remain to be elucidated. In this study, we examined the effects of CQ and AQ on T cell activation and T cell-mediated immune response. CQ had no significant effect on T cell numbers, but decreased the population of T cells with a high division rate. However, AQ treatment significantly increased the number of cells with low division rates and eliminated cells with high division rates, resulting in the inhibition of T cell proliferation triggered by T cell receptor stimulation, of which inhibition occurred in developing effector T helper and regulatory T cells, regardless of the different exogenous cytokines. Interestingly, the cyclin-dependent kinase inhibitor p21 was significantly and dose-dependently increased by CQ, and more potently by AQ, while other cell cycle regulators were unchanged. Both CQ and AQ elevated the transcription level of p21 though the activation of p53, but also blocked p21 protein degradation in the presence of cycloheximide, causing p21 protein accumulation mainly in the nucleus. Sustained treatment of developing T cells with either CQ or AQ suppressed IFN-γ production in a dose dependent manner and potently inhibited the differentiation of IFN-γ-producing Th1 cells. These results demonstrate that CQ and AQ increase the expression level of p21 and inhibit T cell proliferation and the development of IFN-γ-producing Th1 cells, thereby revealing beneficial roles in treating a wide range of chronic inflammatory diseases mediated by inflammatory T cells. -- Highlights: •T cell division rates are suppressed by chloroquine and amodiaquine treatment. •Chloroquine and amodiaquine potently increased the p21 expression. •The p21 induction is

  3. Anti-inflammatory activity of chloroquine and amodiaquine through p21-mediated suppression of T cell proliferation and Th1 cell differentiation

    Energy Technology Data Exchange (ETDEWEB)

    Oh, Sera; Shin, Ji Hyun; Jang, Eun Jung; Won, Hee Yeon; Kim, Hyo Kyeong; Jeong, Mi- Gyeong [College of Pharmacy and Graduate School of Pharmaceutical Sciences, Ewha Womans University, Seoul 120-750 (Korea, Republic of); Kim, Kwang Soo [Molecular Neurobiology Laboratory, Department of Psychiatry, McLean Hospital, Harvard Medical School, Belmont, MA 02478 (United States); Hwang, Eun Sook, E-mail: eshwang@ewha.ac.kr [College of Pharmacy and Graduate School of Pharmaceutical Sciences, Ewha Womans University, Seoul 120-750 (Korea, Republic of)

    2016-05-27

    Chloroquine (CQ) and amodiaquine (AQ) have been used for treating or preventing malaria for decades, and their application has expanded into treating inflammatory disease in humans. CQ and AQ are applicable for controlling rheumatoid arthritis, but their molecular mechanisms of anti-inflammatory activity remain to be elucidated. In this study, we examined the effects of CQ and AQ on T cell activation and T cell-mediated immune response. CQ had no significant effect on T cell numbers, but decreased the population of T cells with a high division rate. However, AQ treatment significantly increased the number of cells with low division rates and eliminated cells with high division rates, resulting in the inhibition of T cell proliferation triggered by T cell receptor stimulation, of which inhibition occurred in developing effector T helper and regulatory T cells, regardless of the different exogenous cytokines. Interestingly, the cyclin-dependent kinase inhibitor p21 was significantly and dose-dependently increased by CQ, and more potently by AQ, while other cell cycle regulators were unchanged. Both CQ and AQ elevated the transcription level of p21 though the activation of p53, but also blocked p21 protein degradation in the presence of cycloheximide, causing p21 protein accumulation mainly in the nucleus. Sustained treatment of developing T cells with either CQ or AQ suppressed IFN-γ production in a dose dependent manner and potently inhibited the differentiation of IFN-γ-producing Th1 cells. These results demonstrate that CQ and AQ increase the expression level of p21 and inhibit T cell proliferation and the development of IFN-γ-producing Th1 cells, thereby revealing beneficial roles in treating a wide range of chronic inflammatory diseases mediated by inflammatory T cells. -- Highlights: •T cell division rates are suppressed by chloroquine and amodiaquine treatment. •Chloroquine and amodiaquine potently increased the p21 expression. •The p21 induction is

  4. T-cell proliferative responses following sepsis in neonatal rats.

    Science.gov (United States)

    Dallal, Ousama; Ravindranath, Thyyar M; Choudhry, Mashkoor A; Kohn, Annamarie; Muraskas, Jonathan K; Namak, Shahla Y; Alattar, Mohammad H; Sayeed, Mohammed M

    2003-01-01

    Both experimental and clinical evidence suggest a suppression of T-cell function in burn and sepsis. The objective of the present study was to evaluate splenocyte and purified T-cell proliferative response and IL-2 production in septic neonatal rats. We also examined if alterations in T-cell proliferation and IL-2 production in neonatal sepsis is due to elevation in PGE2. PGE2 is known to play a significant role in T-cell suppression during sepsis in adults. Sepsis was induced in 15-day-old neonatal Sprague-Dawley rats by implanting 0.1 cm3 of fecal pellet impregnated with Escherichia coli (50 CFU) and Bacteroides fragilis (10(3) CFU). Animals receiving fecal pellets without the bacteria were designated as sterile. A group of septic and sterile rats were treated with PGE2 synthesis inhibitors, NS398 and resveratrol. These treatments of animals allowed us to evaluate the role of PGE2 in T-cell suppression during neonatal sepsis. Splenocytes as well as purified T cells were prepared and then proliferative response and IL-2 productive capacities were measured. A significant suppression of splenocyte proliferation and IL-2 production was noticed in both sterile and septic animals compared to the T cells from unoperated control rats. In contrast, the proliferation and IL-2 production by nylon wool purified T cells in sterile rats was not significantly different from control rats, whereas, a significant suppression in Con A-mediated T-cell proliferation and IL-2 production noticed in septic rat T cells compared to the sterile and control rat T cells. Such decrease in T-cell proliferation and IL-2 production was accompanied with 20-25% deaths in neonates implanted with septic pellets. No mortality was noted in sterile-implanted neonates. Treatment of animals with COX-1 inhibitor had no effect on T-cell proliferation response in both septic and sterile groups, whereas COX-2 inhibitor abrogated the decrease in T-cell proliferative response in the septic group. The treatment

  5. In vivo proliferation of naïve and memory influenza-specific CD8(+) T cells

    DEFF Research Database (Denmark)

    Flynn, K J; Riberdy, J M; Christensen, Jan Pravsgaard

    1999-01-01

    days. The greatly expanded population of CD8(+)NPP(+) memory T cells in the lymphoid tissue of secondarily challenged mice declines progressively in mean prevalence over the ensuing 100 days, despite the fact that at least some of these lymphocytes continue to cycle. The recall of cell......The virus-specific CD8(+) T cell response has been analyzed through the development, effector, and recovery phases of primary and secondary influenza pneumonia. Apparently, most, if not all, memory T cells expressing clonotypic receptors that bind a tetrameric complex of influenza nucleoprotein (NP......)(366-374) peptide+H-2D(b) (NPP) are induced to divide during the course of this localized respiratory infection. The replicative phase of the recall response ends about the time that virus can no longer be recovered from the lung, whereas some primary CD8(+)NPP(+) T cells may proliferate for a few more...

  6. Programmed cell death-10 enhances proliferation and protects malignant T cells from apoptosis

    DEFF Research Database (Denmark)

    Lauenborg, Britt; Kopp, Katharina; Krejsgaard, Thorbjørn

    2010-01-01

    is associated with serine/threonine kinases and phosphatases and modulates the extracellular signal-regulated kinase pathway suggesting a role in the regulation of cellular growth. Here we provide evidence of a constitutive expression of PDCD10 in malignant T cells and cell lines from peripheral blood......, whereas an activator of Jak3 and NF-¿B, interleukin-2 (IL-2), enhances PDCD10 expression. Functional data show that PDCD10 depletion by small interfering RNA induces apoptosis and decreases proliferation of the sensitive cells. To our knowledge, these data provide the first functional link between PDCD10...

  7. Pathophysiological hypoxia affects the redox state and IL-2 signalling of human CD4+ T cells and concomitantly impairs survival and proliferation.

    Science.gov (United States)

    Gaber, Timo; Tran, Cam Loan; Schellmann, Saskia; Hahne, Martin; Strehl, Cindy; Hoff, Paula; Radbruch, Andreas; Burmester, Gerd-Rüdiger; Buttgereit, Frank

    2013-06-01

    Inflamed areas are characterized by infiltration of immune cells, local hypoxia and alterations of cellular redox states. We investigated the impact of hypoxia on survival, proliferation, cytokine secretion, intracellular energy and redox state of human CD4(+) T cells. We found that pathophysiological hypoxia (<2% O2 ) significantly decreased CD4(+) T-cell survival after mitogenic stimulation. This effect was not due to an increased caspase-3/7-mediated apoptosis or adenosine-5'-triphosphate (ATP) consumption/depletion. However, the ability of stimulated T cells to proliferate was reduced under hypoxic conditions, despite increased expression of CD25. Pathophysiological hypoxia was also found to modify intracellular ROS (iROS) levels in stimulated T cells over time as compared with levels found in normoxia. Physiological hypoxia (5% O2 ) did not decrease CD4(+) T-cell survival and proliferation or modify iROS levels as compared with normoxia. We conclude that pathophysiological hypoxia affects T-cell proliferation and viability via disturbed IL-2R signalling downstream of STAT5a phosphorylation, but not as a result of impaired cellular energy homeostasis. We suggest iROS links early events in T-cell stimulation to the inhibition of the lymphoproliferative response under pathophysiological hypoxic conditions. The level of iROS may therefore act as a mediator of immune functions leading to down-regulation of long-term T-cell activity in inflamed tissues. © 2013 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  8. Leu-9 (CD 7) positivity in acute leukemias: a marker of T-cell lineage?

    Science.gov (United States)

    Ben-Ezra, J; Winberg, C D; Wu, A; Rappaport, H

    1987-01-01

    Monoclonal antibody Leu-9 (CD 7) has been reported to be a sensitive and specific marker for T-cell lineage in leukemic processes, since it is positive in patients whose leukemic cells fail to express other T-cell antigens. To test whether Leu-9 is indeed specific for T-cell leukemias, we examined in detail 10 cases of acute leukemia in which reactions were positive for Leu-9 and negative for other T-cell-associated markers including T-11, Leu-1, T-3, and E-rosettes. Morphologically and cytochemically, 2 of these 10 leukemias were classified as lymphoblastic, 4 as myeloblastic, 2 as monoblastic, 1 as megakaryoblastic, and 1 as undifferentiated. The case of acute megakaryoblastic leukemia is the first reported case to be Leu-9 positive. None of the 10 were TdT positive. Of six cases (two monoblastic, one lymphoblastic, one myeloblastic, one megakaryoblastic, and one undifferentiated) in which we evaluated for DNA gene rearrangements, only one, a peroxidase-positive leukemia, showed a novel band on study of the T-cell-receptor beta-chain gene. We therefore conclude that Leu-9 is not a specific marker to T-cell lineage and that, in the absence of other supporting data, Leu-9 positivity should not be used as the sole basis of classifying an acute leukemia as being T-cell derived.

  9. T-cell acute lymphoblastic leukemia associated with complex karyotype and SET-NUP214 rearrangement: a case study and review of the literature.

    Science.gov (United States)

    Lee, Sang-Guk; Park, Tae Sung; Cho, Sun Young; Lim, Gayoung; Park, Gwang Jin; Oh, Seung Hwan; Cho, Eun Hae; Chong, So Young; Huh, Ji Young

    2011-01-01

    SET-NUP214 rearrangements have been rarely reported in T-cell acute lymphoblastic leukemia (T-ALL), acute undifferentiated leukemia, and acute myeloid leukemia, and most documented cases have been associated with normal karyotypes in conventional cytogenetic analyses. Here, we describe a novel case of T-ALL associated with a mediastinal mass and a SET-NUP214 rearrangement, which was masked by a complex karyotype at the time of initial diagnosis. Using multiplex reverse transcriptase-polymerase chain reaction analysis, we detected a cryptic SET-NUP214 rearrangement in our patient. As only 11 cases (including the present study) of T-ALL with SET-NUP214 rearrangement have been reported, the clinical features and treatment outcomes have not been fully determined. Further studies are necessary to evaluate the incidence of SET-NUP214 rearrangement in T-ALL patients and the treatment responses as well as prognosis of these patients.

  10. Expansion of mycobacterium-reactive gamma delta T cells by a subset of memory helper T cells.

    Science.gov (United States)

    Vila, L M; Haftel, H M; Park, H S; Lin, M S; Romzek, N C; Hanash, S M; Holoshitz, J

    1995-04-01

    Human gamma delta T cells expressing the V gamma 9/V delta 2 T-cell receptor have been previously found to proliferate in response to certain microorganisms and to expand throughout life, presumably because of extrathymic activation by foreign antigens. In vitro expansion of V gamma 9/V delta 2 cells by mycobacteria has been previously shown to be dependent on accessory cells. In order to gain an insight into the mechanisms involved in the expansion of these cells, we have undertaken to identify the peripheral blood subset of cells on which proliferation of V gamma 9/V delta 2 cells in response to mycobacteria is dependent. Contrary to their role in antigen presentation to alpha beta T cells, professional antigen-presenting cells, such as monocytes, B cells, and dendritic cells, were unable to provide the cellular support for the expansion of V gamma 9/V delta 2 cells. Selective depletion of T-cell subsets, as well as the use of highly purified T-cell populations, indicated that the only subset of peripheral blood cells that could expand V gamma 9/V delta 2 cells were CD4+ CD45RO+ CD7- alpha beta T cells. These cells underwent distinct intracellular signaling events after stimulation with the mycobacterial antigen. Expansion of V gamma 9/V delta 2 cells by alpha beta T cells was dependent on cell-cell contact. This is the first evidence that a small subset of the memory helper T-cell population is exclusively responsible for the peripheral expansion of V gamma 9/V delta 2 cells. These data illustrate a unique aspect of antigen recognition by gamma delta T cells and provide new means to study their immune defense role.

  11. The T-ALL related gene BCL11B regulates the initial stages of human T-cell differentiation.

    Science.gov (United States)

    Ha, V L; Luong, A; Li, F; Casero, D; Malvar, J; Kim, Y M; Bhatia, R; Crooks, G M; Parekh, C

    2017-11-01

    The initial stages of T-cell differentiation are characterized by a progressive commitment to the T-cell lineage, a process that involves the loss of alternative (myelo-erythroid, NK, B) lineage potentials. Aberrant differentiation during these stages can result in T-cell acute lymphoblastic leukemia (T-ALL). However, the mechanisms regulating the initial stages of human T-cell differentiation are obscure. Through loss of function studies, we showed BCL11B, a transcription factor recurrently mutated T-ALL, is essential for T-lineage commitment, particularly the repression of NK and myeloid potentials, and the induction of T-lineage genes, during the initial stages of human T-cell differentiation. In gain of function studies, BCL11B inhibited growth of and induced a T-lineage transcriptional program in T-ALL cells. We found previously unknown differentiation stage-specific DNA binding of BCL11B at multiple T-lineage genes; target genes showed BCL11B-dependent expression, suggesting a transcriptional activator role for BCL11B at these genes. Transcriptional analyses revealed differences in the regulatory actions of BCL11B between human and murine thymopoiesis. Our studies show BCL11B is a key regulator of the initial stages of human T-cell differentiation and delineate the BCL11B transcriptional program, enabling the dissection of the underpinnings of normal T-cell differentiation and providing a resource for understanding dysregulations in T-ALL.

  12. Ethanol exacerbates T cell dysfunction after thermal injury.

    Science.gov (United States)

    Choudhry, M A; Messingham, K A; Namak, S; Colantoni, A; Fontanilla, C V; Duffner, L A; Sayeed, M M; Kovacs, E J

    2000-07-01

    To understand the mechanism of suppressed immunity following alcohol consumption and thermal injury, we analyzed T cell functions in a mouse model of acute alcohol exposure and burn injury. Mice with blood alcohol levels at approximately 100 mg/dl were given a 15% scald or sham injury. Mice were sacrificed 48 h after injury. Our data demonstrated a 20-25% decrease in Con A-mediated splenic T cell proliferation (p<0.01) and 45-50% decrease in interleukin-2 (IL-2) production (p<0.01) following burn injury compared to the T cells from sham animals. A further decrease in the proliferation (25-30%) and IL-2 production (40-45%) was detected in T cells derived from burned animals receiving alcohol as compared to burn alone. No significant change in the proliferation and IL-2 production was observed in splenic T cells derived from sham-injured mice regardless of alcohol exposure. Additionally, there was no demonstrable difference in splenocyte apoptosis in any treatment group. These results suggest that alcohol consumption prior to burn injury causes a greater decrease in T cell proliferation and IL-2 production compared to either burn or alcohol injury alone that may further attenuate the cell-mediated immunity and thus enhance susceptibility to infection.

  13. Proliferation and apoptosis of lamina propria CD4+ T cells from scid mice with inflammatory bowel disease

    DEFF Research Database (Denmark)

    Bregenholt, S; Reimann, J; Claesson, Mogens Helweg

    1998-01-01

    Scid mice transplanted with low numbers of syngeneic CD4+ T cells, develop a chronic and lethal inflammatory bowel disease (IBD) within 4-6 months. We have used in vivo 5-bromo2-deoxy-uridine (BrdU) labeling to assess the proliferation of lamina propria-derived CD4+ T cells in diseased scid mice....... The hourly rate of renewal of colonic lamina propria CD4+ T cells in diseased mice was 7% compared with 1.5% in normal BALB/c control mice. Transplantation of scid mice with in vitro activated CD4+ T cells accelerated the disease onset and development in a cell dose-dependent fashion when compared with non......-activated CD4+ T cells. In pulse-chase experiments it was shown that BrdU-labeled cells disappeared rapidly from the lamina propria of diseased mice. DNA analysis revealed that this was due to the presence of nearly four times as many apoptotic CD4+ T cells in diseased than in control mice. Further analyses...

  14. [Acute lymphoblastic leukemia of T progenitors: from biology to clinics].

    Science.gov (United States)

    Genescà, Eulàlia; Ribera, Jordi; Ribera, Josep-Maria

    2015-03-09

    Acute lymphoblastic leukemia (ALL) is the most common cancer in children and the main cause of morbidity among childhood blood disorders. There are 2 subtypes according to the affected lymphoid progenitor: B-ALL and T-ALL. The T-ALL is the less common and, although historically was associated with poor prognosis in both adults and children, at present, treatment outcomes do not differ significantly between the 2 types of ALL. The T-ALL subtype is the most complex and heterogeneous at the genetic level and currently the one with less new therapeutic alternatives available. This trend is changing thanks to the remarkable progress upon understanding its biology. This review summarizes the most recent and important biological findings in T-ALL and their possible therapeutic implications. Copyright © 2013 Elsevier España, S.L.U. All rights reserved.

  15. Multipotent Adult Progenitor Cells Suppress T Cell Activation in In Vivo Models of Homeostatic Proliferation in a Prostaglandin E2-Dependent Manner

    Science.gov (United States)

    Carty, Fiona; Corbett, Jennifer M.; Cunha, João Paulo M. C. M.; Reading, James L.; Tree, Timothy I. M.; Ting, Anthony E.; Stubblefield, Samantha R.; English, Karen

    2018-01-01

    Lymphodepletion strategies are used in the setting of transplantation (including bone marrow, hematopoietic cell, and solid organ) to create space or to prevent allograft rejection and graft versus host disease. Following lymphodepletion, there is an excess of IL-7 available, and T cells that escape depletion respond to this cytokine undergoing accelerated proliferation. Moreover, this environment promotes the skew of T cells to a Th1 pro-inflammatory phenotype. Existing immunosuppressive regimens fail to control this homeostatic proliferative (HP) response, and thus the development of strategies to successfully control HP while sparing T cell reconstitution (providing a functioning immune system) represents a significant unmet need in patients requiring lymphodepletion. Multipotent adult progenitor cells (MAPC®) have the capacity to control T cell proliferation and Th1 cytokine production. Herein, this study shows that MAPC cells suppressed anti-thymocyte globulin-induced cytokine production but spared T cell reconstitution in a pre-clinical model of lymphodepletion. Importantly, MAPC cells administered intraperitoneally were efficacious in suppressing interferon-γ production and in promoting the expansion of regulatory T cells in the lymph nodes. MAPC cells administered intraperitoneally accumulated in the omentum but were not present in the spleen suggesting a role for soluble factors. MAPC cells suppressed lymphopenia-induced cytokine production in a prostaglandin E2-dependent manner. This study suggests that MAPC cell therapy may be useful as a novel strategy to target lymphopenia-induced pathogenic T cell responses in lymphodepleted patients. PMID:29740426

  16. Potent anti-leukemia activities of humanized CD19-targeted CAR-T cells in patients with relapsed/refractory acute lymphoblastic leukemia.

    Science.gov (United States)

    Cao, Jiang; Wang, Gang; Cheng, Hai; Wei, Chen; Qi, Kunming; Sang, Wei; Zhenyu, Li; Shi, Ming; Li, Huizhong; Qiao, Jianlin; Pan, Bin; Zhao, Jing; Wu, Qingyun; Zeng, Lingyu; Niu, Mingshan; Jing, Guangjun; Zheng, Junnian; Xu, Kailin

    2018-04-10

    Chimeric antigen receptor T (CAR-T) cell therapy has shown promising results for relapsed/refractory (R/R) acute lymphoblastic leukemia (ALL). The immune response induced by murine single-chain variable fragment (scFv) of the CAR may limit CAR-T cell persistence and thus increases the risk of leukemia relapse. In this study, we developed a novel humanized scFv from the murine FMC63 antibody. A total of 18 R/R ALL patients with or without prior murine CD19 CAR-T therapy were treated with humanized CD19-targeted CAR-T cells (hCART19s). After lymphodepletion chemotherapy with cyclophosphamide and fludarabine, the patients received a single dose (1 × 10 6 /kg) of autologous hCART19s infusion. Among the 14 patients without previous CAR-T therapy, 13 (92.9%) achieved complete remission (CR) or CR with incomplete count recovery (CRi) on day 30, whereas 1 of the 3 patients who failed a second murine CAR-T infusion achieved CR after hCART19s infusion. At day 180, the overall and leukemia-free survival rates were 65.8% and 71.4%, respectively. The cumulative incidence of relapse was 22.6%, and the non-relapse mortality rate was 7.1%. During treatment, 13 patients developed grade 1-2 cytokine release syndrome (CRS), 4 patients developed grade 3-5 CRS, and 1 patient experienced reversible neurotoxicity. These results indicated that hCART19s could induce remission in patients with R/R B-ALL, especially in patients who received a reinfusion of murine CAR-T. This article is protected by copyright. All rights reserved. © 2018 Wiley Periodicals, Inc.

  17. Quetiapine, an atypical antipsychotic, is protective against autoimmune-mediated demyelination by inhibiting effector T cell proliferation.

    Directory of Open Access Journals (Sweden)

    Feng Mei

    Full Text Available Quetiapine (Que, a commonly used atypical antipsychotic drug (APD, can prevent myelin from breakdown without immune attack. Multiple sclerosis (MS, an autoimmune reactive inflammation demyelinating disease, is triggered by activated myelin-specific T lymphocytes (T cells. In this study, we investigated the potential efficacy of Que as an immune-modulating therapeutic agent for experimental autoimmune encephalomyelitis (EAE, a mouse model for MS. Que treatment was initiated on the onset of MOG(35-55 peptide induced EAE mice and the efficacy of Que on modulating the immune response was determined by Flow Cytometry through analyzing CD4(+/CD8(+ populations and the proliferation of effector T cells (CD4(+CD25(- in peripheral immune organs. Our results show that Que dramatically attenuates the severity of EAE symptoms. Que treatment decreases the extent of CD4(+/CD8(+ T cell infiltration into the spinal cord and suppresses local glial activation, thereby diminishing the loss of mature oligodendrocytes and myelin breakdown in the spinal cord of EAE mice. Our results further demonstrate that Que treatment decreases the CD4(+/CD8(+ T cell populations in lymph nodes and spleens of EAE mice and inhibits either MOG(35-55 or anti-CD3 induced proliferation as well as IL-2 production of effector T cells (CD4(+CD25(- isolated from EAE mice spleen. Together, these findings suggest that Que displays an immune-modulating role during the course of EAE, and thus may be a promising candidate for treatment of MS.

  18. Effect of polysaccharides of ganoderma lucidum (PGL) on cell cycle and proliferation of NIH3T3 fibroblast exposed to γ-rays

    International Nuclear Information System (INIS)

    Ji Xiuqing; Wu Shiling; Zhou Yinghui; Xu Lan

    2001-01-01

    Objective: To study the effects of γ-irradiation on cell cycle and proliferation of fibroblasts and the radioprotective effect of PGL in term of cellular level. Methods: The cells in the control group and PGL (50 mg/L. 100 mg/L. 150 mg/L) groups were irradiated with 15 Gy γ-rays. The cell cycle and proliferation of NIH3T3 cells were determined by flow cytometry after irradiation within 12 h. Results: The percentage of G 0 -G 1 phase was 52.76% in the positive control group. Compared with the negative control group (90.9%), the proliferation of NIH3T3 was promoted significantly (P 0 -G 1 phases in the GPL (50 mg/L, 100 mg/L, 150 mg/L) groups were 66.17%, 71.73%, 76.10% respectively, the proliferation of NIH3T3 cells was inhibited by adding GPL. compared with the positive control group, in the 50 mg/L group P < 0.05, in the 100 mg/L and 150 mg/L groups P < 0.01. It was found that the apoptosis of NIH3T3 cells had little change after comparing non-irradiated group with the irradiated groups. Conclusion: Radiation with γ-rays at a dose of 15 Gy, can significantly stimulate proliferation of NIH3T3 cells, but no induced apoptosis can not be achieve within 12 h after irradiation. PGL can inhibit cell proliferation, so PGL has radioprotective activity on cell levels

  19. Conventional CD4+ T cells present bacterial antigens to induce cytotoxic and memory CD8+ T cell responses.

    Science.gov (United States)

    Cruz-Adalia, Aránzazu; Ramirez-Santiago, Guillermo; Osuna-Pérez, Jesús; Torres-Torresano, Mónica; Zorita, Virgina; Martínez-Riaño, Ana; Boccasavia, Viola; Borroto, Aldo; Martínez Del Hoyo, Gloria; González-Granado, José María; Alarcón, Balbino; Sánchez-Madrid, Francisco; Veiga, Esteban

    2017-11-17

    Bacterial phagocytosis and antigen cross-presentation to activate CD8 + T cells are principal functions of professional antigen presenting cells. However, conventional CD4 + T cells also capture and kill bacteria from infected dendritic cells in a process termed transphagocytosis (also known as transinfection). Here, we show that transphagocytic T cells present bacterial antigens to naive CD8 + T cells, which proliferate and become cytotoxic in response. CD4 + T-cell-mediated antigen presentation also occurs in vivo in the course of infection, and induces the generation of central memory CD8 + T cells with low PD-1 expression. Moreover, transphagocytic CD4 + T cells induce protective anti-tumour immune responses by priming CD8 + T cells, highlighting the potential of CD4 + T cells as a tool for cancer immunotherapy.

  20. The thioredoxin-1 system is essential for fueling DNA synthesis during T-cell metabolic reprogramming and proliferation.

    Science.gov (United States)

    Muri, Jonathan; Heer, Sebastian; Matsushita, Mai; Pohlmeier, Lea; Tortola, Luigi; Fuhrer, Tobias; Conrad, Marcus; Zamboni, Nicola; Kisielow, Jan; Kopf, Manfred

    2018-05-10

    The thioredoxin-1 (Trx1) system is an important contributor to cellular redox balance and is a sensor of energy and glucose metabolism. Here we show critical c-Myc-dependent activation of the Trx1 system during thymocyte and peripheral T-cell proliferation, but repression during T-cell quiescence. Deletion of thioredoxin reductase-1 (Txnrd1) prevents expansion the CD4 - CD8 - thymocyte population, whereas Txnrd1 deletion in CD4 + CD8 + thymocytes does not affect further maturation and peripheral homeostasis of αβT cells. However, Txnrd1 is critical for expansion of the activated T-cell population during viral and parasite infection. Metabolomics show that TrxR1 is essential for the last step of nucleotide biosynthesis by donating reducing equivalents to ribonucleotide reductase. Impaired availability of 2'-deoxyribonucleotides induces the DNA damage response and cell cycle arrest of Txnrd1-deficient T cells. These results uncover a pivotal function of the Trx1 system in metabolic reprogramming of thymic and peripheral T cells and provide a rationale for targeting Txnrd1 in T-cell leukemia.

  1. Culture promotes transfer of thyroid epithelial cell hyperplasia and proliferation by reducing regulatory T cell numbers.

    Science.gov (United States)

    Kayes, Timothy D; Braley-Mullen, Helen

    2013-01-01

    IFN-γ(-/-) NOD.H-2h4 mice develop a spontaneous autoimmune thyroid disease, thyroid epithelial cell hyperplasia and proliferation (TEC H/P) when given NaI in their water for 7+ mo. TEC H/P can be transferred to IFN-γ(-/-) SCID mice by splenocytes from mice with severe (4-5+) disease, and transfer of TEC H/P is improved when splenocytes are cultured prior to transfer. Older (9+ mo) IFN-γ(-/-) NOD.H-2h4 mice have elevated numbers of FoxP3(+) T reg cells, up to 2-fold greater than younger (2 mo) mice. During culture, the number of T reg decreases and this allows the improved transfer of TEC H/P. Co-culture with IL-2 prior to transfer prevents the decrease of T reg and improves their in vitro suppressive ability resulting in reduced TEC H/P in recipient mice. Therefore, culturing splenocytes improves transfer of TEC H/P by reducing the number of T reg and IL-2 inhibits transfer by preserving T reg number and function. Copyright © 2013 Elsevier Inc. All rights reserved.

  2. Parathyroid hormone dependent T cell proliferation in uremic rats

    DEFF Research Database (Denmark)

    Lewin, E; Ladefoged, Jens; Brandi, L

    1993-01-01

    Chronic renal failure (CRF) is combined with an impairment of the immune system. The T cell may be a target for the action of parathyroid hormone (PTH). Rats with CRF have high blood levels of PTH. Therefore, the present investigation examined some aspects of the T cell function in both normal...... and CRF rats before and after parathyroidectomy and after an isogenic kidney transplantation. The T cell proliferative response to phytohemagglutinin (PHA) stimulation was significantly higher in peripheral blood mononuclear cell (PBMC) cultures obtained from CRF rats than from normal rats. After...... parathyroidectomy the T cells of normal as well as of uremic rats could still be significantly stimulated by PHA, but now no significant difference was seen. When CRF was reversed after an isogenic kidney transplantation and PTH reversed to levels in the normal range, the T cell proliferative response to PHA...

  3. TLR5 signaling enhances the proliferation of human allogeneic CD40-activated B cell induced CD4hiCD25+ regulatory T cells.

    Directory of Open Access Journals (Sweden)

    Ping-Lung Chan

    Full Text Available Although diverse functions of different toll-like receptors (TLR on human natural regulatory T cells have been demonstrated recently, the role of TLR-related signals on human induced regulatory T cells remain elusive. Previously our group developed an ex vivo high-efficient system in generating human alloantigen-specific CD4(hiCD25(+ regulatory T cells from naïve CD4(+CD25(- T cells using allogeneic CD40-activated B cells as stimulators. In this study, we investigated the role of TLR5-related signals on the generation and function of these novel CD4(hiCD25(+ regulatory T cells. It was found that induced CD4(hiCD25(+ regulatory T cells expressed an up-regulated level of TLR5 compared to their precursors. The blockade of TLR5 using anti-TLR5 antibodies during the co-culture decreased CD4(hiCD25(+ regulatory T cells proliferation by induction of S phase arrest. The S phase arrest was associated with reduced ERK1/2 phosphorylation. However, TLR5 blockade did not decrease the CTLA-4, GITR and FOXP3 expressions, and the suppressive function of CD4(hiCD25(+ regulatory T cells. In conclusion, we discovered a novel function of TLR5-related signaling in enhancing the proliferation of CD4(hiCD25(+ regulatory T cells by promoting S phase progress but not involved in the suppressive function of human CD40-activated B cell-induced CD4(hiCD25(+ regulatory T cells, suggesting a novel role of TLR5-related signals in the generation of induced regulatory T cells.

  4. ATF3, an HTLV-1 bZip factor binding protein, promotes proliferation of adult T-cell leukemia cells

    Directory of Open Access Journals (Sweden)

    Ohshima Koichi

    2011-03-01

    Full Text Available Abstract Background Adult T-cell leukemia (ATL is an aggressive malignancy of CD4+ T-cells caused by human T-cell leukemia virus type 1 (HTLV-1. The HTLV-1 bZIP factor (HBZ gene, which is encoded by the minus strand of the viral genome, is expressed as an antisense transcript in all ATL cases. By using yeast two-hybrid screening, we identified activating transcription factor 3 (ATF3 as an HBZ-interacting protein. ATF3 has been reported to be expressed in ATL cells, but its biological significance is not known. Results Immunoprecipitation analysis confirmed that ATF3 interacts with HBZ. Expression of ATF3 was upregulated in ATL cell lines and fresh ATL cases. Reporter assay revealed that ATF3 could interfere with the HTLV-1 Tax's transactivation of the 5' proviral long terminal repeat (LTR, doing so by affecting the ATF/CRE site, as well as HBZ. Suppressing ATF3 expression inhibited proliferation and strongly reduced the viability of ATL cells. As mechanisms of growth-promoting activity of ATF3, comparative expression profiling of ATF3 knockdown cells identified candidate genes that are critical for the cell cycle and cell death, including cell division cycle 2 (CDC2 and cyclin E2. ATF3 also enhanced p53 transcriptional activity, but this activity was suppressed by HBZ. Conclusions Thus, ATF3 expression has positive and negative effects on the proliferation and survival of ATL cells. HBZ impedes its negative effects, leaving ATF3 to promote proliferation of ATL cells via mechanisms including upregulation of CDC2 and cyclin E2. Both HBZ and ATF3 suppress Tax expression, which enables infected cells to escape the host immune system.

  5. Different Subsets of T Cells, Memory, Effector Functions, and CAR-T Immunotherapy.

    Science.gov (United States)

    Golubovskaya, Vita; Wu, Lijun

    2016-03-15

    This review is focused on different subsets of T cells: CD4 and CD8, memory and effector functions, and their role in CAR-T therapy--a cellular adoptive immunotherapy with T cells expressing chimeric antigen receptor. The CAR-T cells recognize tumor antigens and induce cytotoxic activities against tumor cells. Recently, differences in T cell functions and the role of memory and effector T cells were shown to be important in CAR-T cell immunotherapy. The CD4⁺ subsets (Th1, Th2, Th9, Th17, Th22, Treg, and Tfh) and CD8⁺ memory and effector subsets differ in extra-cellular (CD25, CD45RO, CD45RA, CCR-7, L-Selectin [CD62L], etc.); intracellular markers (FOXP3); epigenetic and genetic programs; and metabolic pathways (catabolic or anabolic); and these differences can be modulated to improve CAR-T therapy. In addition, CD4⁺ Treg cells suppress the efficacy of CAR-T cell therapy, and different approaches to overcome this suppression are discussed in this review. Thus, next-generation CAR-T immunotherapy can be improved, based on our knowledge of T cell subsets functions, differentiation, proliferation, and signaling pathways to generate more active CAR-T cells against tumors.

  6. Different Subsets of T Cells, Memory, Effector Functions, and CAR-T Immunotherapy

    Directory of Open Access Journals (Sweden)

    Vita Golubovskaya

    2016-03-01

    Full Text Available This review is focused on different subsets of T cells: CD4 and CD8, memory and effector functions, and their role in CAR-T therapy––a cellular adoptive immunotherapy with T cells expressing chimeric antigen receptor. The CAR-T cells recognize tumor antigens and induce cytotoxic activities against tumor cells. Recently, differences in T cell functions and the role of memory and effector T cells were shown to be important in CAR-T cell immunotherapy. The CD4+ subsets (Th1, Th2, Th9, Th17, Th22, Treg, and Tfh and CD8+ memory and effector subsets differ in extra-cellular (CD25, CD45RO, CD45RA, CCR-7, L-Selectin [CD62L], etc.; intracellular markers (FOXP3; epigenetic and genetic programs; and metabolic pathways (catabolic or anabolic; and these differences can be modulated to improve CAR-T therapy. In addition, CD4+ Treg cells suppress the efficacy of CAR-T cell therapy, and different approaches to overcome this suppression are discussed in this review. Thus, next-generation CAR-T immunotherapy can be improved, based on our knowledge of T cell subsets functions, differentiation, proliferation, and signaling pathways to generate more active CAR-T cells against tumors.

  7. Andrographolide inhibits growth of human T-cell acute lymphoblastic leukemia Jurkat cells by downregulation of PI3K/AKT and upregulation of p38 MAPK pathways

    Science.gov (United States)

    Yang, Tingfang; Yao, Shuluan; Zhang, Xianfeng; Guo, Yan

    2016-01-01

    T-cell acute lymphoblastic leukemia (T-ALL) as a prevalent hematologic malignancy is one of the most common malignant tumors worldwide in children. Andrographolide (Andro), the major active component from Andrographis paniculata, has been shown to possess antitumor activities in several types of cancer cells. However, whether Andro would inhibit T-ALL cell growth remains unclear. In this study, we investigated the cytotoxic effect of Andro on human T-ALL Jurkat cells and explored the mechanisms of cell death. Cell apoptosis was assayed by flow cytometry, and the signaling transduction for Andro was analyzed by Western blotting. The results indicated 10 μg/mL Andro could significantly induce Jurkat cells’ apoptosis, depending on the inhibition of PI3K/AKT pathway. Moreover, Andro-induced apoptosis is enhanced by AKT-selective inhibitor LY294002. ERK- or JNK-selective inhibitors PD98059 and SP600125 had no effect on Andro-induced apoptosis. In addition, p38 inhibitor SB203580 could reverse Andro-induced apoptosis in Jurkat cells. We also found that the protein expression of p-p53 and p-p38 were increased after Andro treatments. The result of an in vivo study also demonstrated Andro’s dose-dependent inhibition in subcutaneous Jurkat xenografts. In conclusion, our findings explained a novel mechanism of drug action by Andro in Jurkat cells and suggested that Andro might be developed into a new candidate therapy for T-ALL patients in the coming days. PMID:27114702

  8. Proliferation of latently infected CD4+ T cells carrying replication-competent HIV-1: Potential role in latent reservoir dynamics

    Science.gov (United States)

    Hosmane, Nina N.; Kwon, Kyungyoon J.; Bruner, Katherine M.; Capoferri, Adam A.; Rosenbloom, Daniel I.S.; Keele, Brandon F.; Ho, Ya-Chi

    2017-01-01

    A latent reservoir for HIV-1 in resting CD4+ T lymphocytes precludes cure. Mechanisms underlying reservoir stability are unclear. Recent studies suggest an unexpected degree of infected cell proliferation in vivo. T cell activation drives proliferation but also reverses latency, resulting in productive infection that generally leads to cell death. In this study, we show that latently infected cells can proliferate in response to mitogens without producing virus, generating progeny cells that can release infectious virus. Thus, assays relying on one round of activation underestimate reservoir size. Sequencing of independent clonal isolates of replication-competent virus revealed that 57% had env sequences identical to other isolates from the same patient. Identity was confirmed by full-genome sequencing and was not attributable to limited viral diversity. Phylogenetic and statistical analysis suggested that identical sequences arose from in vivo proliferation of infected cells, rather than infection of multiple cells by a dominant viral species. The possibility that much of the reservoir arises by cell proliferation presents challenges to cure. PMID:28341641

  9. Proliferation of latently infected CD4+ T cells carrying replication-competent HIV-1: Potential role in latent reservoir dynamics.

    Science.gov (United States)

    Hosmane, Nina N; Kwon, Kyungyoon J; Bruner, Katherine M; Capoferri, Adam A; Beg, Subul; Rosenbloom, Daniel I S; Keele, Brandon F; Ho, Ya-Chi; Siliciano, Janet D; Siliciano, Robert F

    2017-04-03

    A latent reservoir for HIV-1 in resting CD4 + T lymphocytes precludes cure. Mechanisms underlying reservoir stability are unclear. Recent studies suggest an unexpected degree of infected cell proliferation in vivo. T cell activation drives proliferation but also reverses latency, resulting in productive infection that generally leads to cell death. In this study, we show that latently infected cells can proliferate in response to mitogens without producing virus, generating progeny cells that can release infectious virus. Thus, assays relying on one round of activation underestimate reservoir size. Sequencing of independent clonal isolates of replication-competent virus revealed that 57% had env sequences identical to other isolates from the same patient. Identity was confirmed by full-genome sequencing and was not attributable to limited viral diversity. Phylogenetic and statistical analysis suggested that identical sequences arose from in vivo proliferation of infected cells, rather than infection of multiple cells by a dominant viral species. The possibility that much of the reservoir arises by cell proliferation presents challenges to cure. © 2017 Hosmane et al.

  10. Early recovery of circulating immature B cells in B-lymphoblastic leukemia patients after CD19 targeted CAR T cell therapy: A pitfall for minimal residual disease detection.

    Science.gov (United States)

    Xiao, Wenbin; Salem, Dalia; McCoy, Catharine S; Lee, Daniel; Shah, Nirali N; Stetler-Stevenson, Maryalice; Yuan, Constance M

    2017-09-09

    CD19-targeted chimeric-antigen receptor-modified T-cells (CAR-T) are promising in the treatment of refractory B-lymphoblastic leukemia (B-ALL). Minimal residual disease (MRD) detection by multicolor flow cytometry (FCM) is critical to distinguish B-ALL MRD from regenerating, non-neoplastic B-cell populations. FCM was performed on samples from 9 patients with B-ALL treated with CAR-T. All 9 patients showed response to CAR-T. Additionally, FCM revealed circulating CD10 + B cells, potentially mimicking MRD. Circulating CD10+ B-cells were detected in blood from 3 days to 3 months after CAR-T, comprising 73% (median) of B-cells (52-83%, 95%CI). They expressed CD19, CD10, CD20, bright CD9, CD22, CD24, moderate CD38 and dim CD58, but were CD34 (-), with bright CD45 and polyclonal surface light chain immunoglobulin (sIg) expression. A similar CD10 + B-cell subpopulation was detected by marrow FCM, amidst abundant B-cell precursors. These circulating CD10 + B-cells are compatible with immature B-cells, and are a reflection of B-cell recovery within the marrow. They are immunophenotypically distinguishable from residual B-ALL. Expression of light chain sIg and key surface antigens characterizing regenerating B-cell precursors can distinguish immature B-cells from B-ALL MRD and prevent misdiagnosis. © 2017 International Clinical Cytometry Society. © 2017 International Clinical Cytometry Society.

  11. Damage of Neuroblastoma Cell SH-SY5Y Mediated by MPP+ Inhibits Proliferation of T-Cell Leukemia Jurkat by Co-Culture System

    Directory of Open Access Journals (Sweden)

    Fuli Wang

    2014-06-01

    Full Text Available The adaptive immune system has implications in pathology of Parkinson’s disease (PD. Research data demonstrated that the peripheral CD4+ T-cell population decreased in pathogenesis of PD. The effect of damaged dopaminergic neurons on peripheral T cells of PD is still unknown. In this study, we constructed a neuronal and glial cells co-culture model by using human neuroblastoma cells SH-SY5Y and gliomas cells U87. After the co-culture cells were treated with neurotoxin 1-methyl-4-phenylpyridinium (MPP+ for 24 h, the conditioned media was harvested and used to cultivate T-cell leukemia Jurkat cells for another 24 h. We then analyzed the cell proliferation, cell cycle and necrosis effect of Jurkat cells. The results showed that co-culture medium of SH-SY5Y and U87 cells with MPP+ treatment inhibited the proliferation of Jurkat cells compared to control medium without MPP+, even though the same concentration of MPP+ had very little toxicity to the Jurkat cell. Furthermore, co-culture medium with low concentration of MPP+ (100 µM arrested Jurkat cells cycle in G2/M phase through increasing cell cycle division 2 (CDC2 and CyclinB1 expression level, whereas co-culture medium with high concentration of MPP+ (500 µM induced Jurkat cell necrosis through cellular swelling and membrane breakage. Our data implies that damaged dopamine neurons with glial cells can lead to the reduced number or inhibited proliferation activity of peripheral T cells.

  12. Kaposi's-sarcoma-associated-herpesvirus-activated dendritic cells promote HIV-1 trans-infection and suppress CD4+ T cell proliferation

    International Nuclear Information System (INIS)

    Liu, Wan; Qin, Yan; Bai, Lei; Lan, Ke; Wang, Jian-Hua

    2013-01-01

    Infection of Kaposi's sarcoma-associated herpesvirus (KSHV) is commonly occurred in AIDS patients. KSHV and HIV-1 act cooperatively in regulating infection with each other and in human carcinogenesis. Dendritic cells (DCs), as the pivotal cells in host immunity, may be modulated by both viruses, for immunoevasion and dissemination, therefore, the interaction between DCs and each virus has been a prior focus for pathogenesis elucidation. Here, we assessed the potential effect of KSHV on DC–HIV-1 interaction. We found that KSHV stimulation could promote maturation of monocyte-derived DCs (MDDCs) and impaired the ability of MDDCs to drive proliferation of resting CD4 + T cells, demonstrating the immunosuppression induced by KSHV. More importantly, KSHV-stimulated MDDCs could capture more HIV-1 and efficiently transferred these infectious viruses to Hut/CCR5 T cell line. Our results reveal the novel modulation of DC-mediated HIV-1 dissemination by KSHV, and highlight the importance of studying DC–HIV-1 interaction to elucidate HIV/AIDS pathogenesis. - Highlights: ► KSHV impaired the ability of MDDCs to drive proliferation of resting CD4 + T cells. ► KSHV stimulation matured MDDCs and enhanced HIV-1 endocytosis. ► KSHV stimulated MDDCs increased ICAM-1 expression and tighten contact with T cells. ► KSHV-stimulated MDDCs promoted HIV-1 trans-infection of CD4 + T cells

  13. Sodium arsenite-induced inhibition of cell proliferation is related to inhibition of IL-2 mRNA expression in mouse activated T cells

    Energy Technology Data Exchange (ETDEWEB)

    Conde, Patricia; Acosta-Saavedra, Leonor C.; Calderon-Aranda, Emma S. [Centro de Investigacion y de Estudios Avanzados, CINVESTAV, Seccion Toxicologia, P.O. Box 14-740, Mexico, D.F. (Mexico); Goytia-Acevedo, Raquel C. [Universidad Juarez del Estado de Durango, Facultad de Medicina, Gomez Palacio, Durango (Mexico)

    2007-04-15

    A proposed mechanism for the As-induced inhibition of cell proliferation is the inhibition of IL-2 secretion. However, the effects of arsenite on IL-2 mRNA expression or on the ERK pathway in activated-T cells have not yet been described. We examined the effect of arsenite on IL-2 mRNA expression, cell activation and proliferation in PHA-stimulated murine lymphocytes. Arsenite (1 and 10 {mu}M) decreased IL-2 mRNA expression, IL-2 secretion and cell proliferation. Arsenite (10 {mu}M) strongly inhibited ERK-phosphorylation. However, the partial inhibition (50%) of IL-2 mRNA produced by 1 {mu}M, consistent with the effects on IL-2 secretion and cell proliferation, could not be explained by the inhibition of ERK-phosphorylation, which was not affected at this concentration. The inhibition of IL-2 mRNA expression caused by 1 {mu}M could be associated to effects on pathways located downstream or parallel to ERK. Arsenite also decreased early activation (surface CD69{sup +} expression) in both CD4{sup +} and CD8{sup +}, and decreased total CD8{sup +} count without significantly affecting CD4{sup +}, supporting that the cellular immune response mediated by cytotoxic T cells is an arsenic target. Thus, our results suggest that arsenite decreases IL-2 mRNA levels and T-cell activation and proliferation. However, further studies on the effects of arsenite on IL-2 gene transcription and IL-2 mRNA stability are needed. (orig.)

  14. Biological Therapy in Treating Patients With Advanced Myelodysplastic Syndrome, Acute or Chronic Myeloid Leukemia, or Acute Lymphoblastic Leukemia Who Are Undergoing Stem Cell Transplantation

    Science.gov (United States)

    2017-03-27

    Adult Acute Myeloid Leukemia With 11q23 (MLL) Abnormalities; Adult Acute Myeloid Leukemia With Inv(16)(p13;q22); Adult Acute Myeloid Leukemia With t(15;17)(q22;q12); Adult Acute Myeloid Leukemia With t(16;16)(p13;q22); Adult Acute Myeloid Leukemia With t(8;21)(q22;q22); B-cell Adult Acute Lymphoblastic Leukemia; B-cell Childhood Acute Lymphoblastic Leukemia; Childhood Chronic Myelogenous Leukemia; Childhood Myelodysplastic Syndromes; Chronic Myelomonocytic Leukemia; Essential Thrombocythemia; Polycythemia Vera; Previously Treated Myelodysplastic Syndromes; Recurrent Adult Acute Lymphoblastic Leukemia; Recurrent Adult Acute Myeloid Leukemia; Recurrent Childhood Acute Lymphoblastic Leukemia; Recurrent Childhood Acute Myeloid Leukemia; Refractory Anemia With Excess Blasts; Refractory Anemia With Excess Blasts in Transformation; Relapsing Chronic Myelogenous Leukemia; Secondary Acute Myeloid Leukemia; T-cell Adult Acute Lymphoblastic Leukemia; T-cell Childhood Acute Lymphoblastic Leukemia

  15. Ghrelin augments murine T-cell proliferation by activation of the phosphatidylinositol-3-kinase, extracellular signal-regulated kinase and protein kinase C signaling pathways

    Science.gov (United States)

    Lee, Jun Ho; Patel, Kalpesh; Tae, Hyun Jin; Lustig, Ana; Kim, Jie Wan; Mattson, Mark P.; Taub, Dennis D.

    2014-01-01

    Thymic atrophy occurs during normal aging, and is accelerated by exposure to chronic stressors that elevate glucocorticoid levelsand impair the naïve T cell output. The orexigenic hormone ghrelin was recently shown to attenuate age-associated thymic atrophy. Here, we report that ghrelin enhances the proliferation of murine CD4+ primary T cells and a CD4+ T-cell line. Ghrelin induced activation of the ERK1/2 and Akt signaling pathways, via upstream activation of phosphatidylinositol-3-kinase and protein kinase C, to enhance T-cell proliferation. Moreover, ghrelin induced expression of the cell cycle proteins cyclin D1, cyclin E, cyclin-dependent kinase 2 (CDK2) and retinoblastoma phosphorylation. Finally, ghrelin activated the above-mentioned signaling pathways and stimulated thymocyte proliferation in young and older mice in vivo. PMID:25447526

  16. Regulatory activity of azabisphosphonate-capped dendrimers on human CD4+ T cell proliferation enhances ex-vivo expansion of NK cells from PBMCs for immunotherapy

    Directory of Open Access Journals (Sweden)

    Caminade Anne-Marie

    2009-09-01

    Full Text Available Abstract Background Adoptive cell therapy with allogenic NK cells constitutes a promising approach for the treatment of certain malignancies. Such strategies are currently limited by the requirement of an efficient protocol for NK cell expansion. We have developed a method using synthetic nanosized phosphonate-capped dendrimers allowing such expansion. We are showing here that this is due to a specific inhibitory activity towards CD4+ T cell which could lead to further medical applications of this dendrimer. Methods Mononuclear cells from human peripheral blood were used to investigate the immunomodulatory effects of nanosized phosphonate-capped dendrimers on interleukin-2 driven CD4+T cell expansion. Proliferation status was investigated using flow cytometry analysis of CFSE dilution and PI incorporation experiments. Magnetic bead cell sorting was used to address activity towards individual or mixed cell sub-populations. We performed equilibrium binding assay to assess the interaction of fluorescent dendrimers with pure CD4+ T cells. Results Phosphonate-capped dendrimers are inhibiting the activation, and therefore the proliferation; of CD4+ T cells in IL-2 stimulated PBMCs, without affecting their viability. This allows a rapid enrichment of NK cells and further expansion. We found that dendrimer acts directly on T cells, as their regulatory property is maintained when stimulating purified CD4+ T cells with anti-CD3/CD28 microbeads. Performing equilibrium binding assays using a fluorescent analogue, we show that the phosphonate capped-dendrimers are specifically interacting with purified CD4+ T cells. Ultimately, we found that our protocol prevents the IL-2 related expansion of regulatory T cells that would be deleterious for the activity of infused NK cells. Conclusion High yield expansion of NK cells from human PBMCs by phosphonate-capped dendrimers and IL-2 occurs through the specific inhibition of the CD4+ lymphocyte compartment. Given the

  17. CD19/CD22 Chimeric Antigen Receptor T Cells and Chemotherapy in Treating Patients With Recurrent or Refractory CD19 Positive Diffuse Large B-Cell Lymphoma or B Acute Lymphoblastic Leukemia

    Science.gov (United States)

    2018-01-25

    B Acute Lymphoblastic Leukemia; CD19 Positive; Diffuse Large B-Cell Lymphoma Associated With Chronic Inflammation; Diffuse Large B-Cell Lymphoma, Not Otherwise Specified; Epstein-Barr Virus Positive Diffuse Large B-Cell Lymphoma of the Elderly; Minimal Residual Disease; Philadelphia Chromosome Positive; Recurrent Diffuse Large B-Cell Lymphoma; Recurrent Mediastinal (Thymic) Large B-Cell Cell Lymphoma; Refractory Diffuse Large B-Cell Lymphoma; Refractory Mediastinal (Thymic) Large B-Cell Cell Lymphoma; T-Cell/Histiocyte-Rich Large B-Cell Lymphoma

  18. Role of latent membrane protein 1 in chronic active Epstein–Barr virus infection-derived T/NK-cell proliferation

    International Nuclear Information System (INIS)

    Ito, Takuto; Kawazu, Hidetaka; Murata, Takayuki; Iwata, Seiko; Arakawa, Saki; Sato, Yoshitaka; Kuzushima, Kiyotaka; Goshima, Fumi; Kimura, Hiroshi

    2014-01-01

    Epstein–Barr virus (EBV) predominantly infects B cells and causes B-cell lymphomas, such as Burkitt lymphoma and Hodgkin lymphoma. However, it also infects other types of cells, including T and natural killer (NK) cells, and causes disorders, such as chronic active EBV infection (CAEBV) and T/NK-cell lymphoma. The CAEBV is a lymphoproliferative disease with poor prognosis, where EBV-positive T or NK cells grow rapidly, although the molecular mechanisms that cause the cell expansion still remain to be elucidated. EBV-encoded latent membrane protein 1 (LMP1) is an oncogene that can transform some cell types, such as B cells and mouse fibroblasts, and thus may stimulate cell proliferation in CAEBV. Here, we examined the effect of LMP1 on EBV-negative cells using the cells conditionally expressing LMP1, and on CAEBV-derived EBV-positive cells by inhibiting the function of LMP1 using a dominant negative form of LMP1. We demonstrated that LMP1 was responsible for the increased cell proliferation in the cell lines derived from CAEBV, while LMP1 did not give any proliferative advantage to the EBV-negative cell line

  19. [Malignant T-cell lymphoma with osteomyelitis-like bone infiltration].

    Science.gov (United States)

    Mittelmeier, H; Schmitt, O

    1980-01-01

    After a short review on the late literature, existing about various forms of acute lymphoblastic leucemias, it is reported on a rare case of malignant T-cell-Lymphoma with ostemyelitis-like, painfull bone infiltration. The clinical symptoms, as well as differential-diagnostic criterias to other leucemias are described.

  20. A sub-population of circulating porcine gammadelta T cells can act as professional antigen presenting cells.

    Science.gov (United States)

    Takamatsu, H-H; Denyer, M S; Wileman, T E

    2002-09-10

    A sub-population of circulating porcine gammadelta T cells express cell surface antigens associated with antigen presenting cells (APCs), and are able to take up soluble antigen very effectively. Functional antigen presentation by gammadelta T cells to memory helper T cells was studied by inbred pig lymphocytes immunised with ovalbumin (OVA). After removing all conventional APCs from the peripheral blood of immunised pigs, the remaining lymphocytes still proliferated when stimulated with OVA. When gammadelta T cells were further depleted, OVA specific proliferation was abolished, but reconstitution with gammadelta T cells restored proliferation. The proliferation was blocked by monoclonal antibodies (mAb) against MHC class II or CD4, and by pre-treatment of gammadelta T cells with chloroquine. These results indicate that a sub-population of circulating porcine gammadelta T cells act as APCs and present antigen via MHC class II.

  1. Leukaemic infiltration and cytomegalovirus retinitis in a patient with acute T-cell lymphoblastic leukaemia in complete remission.

    Science.gov (United States)

    Saldaña Garrido, J D; Martínez Rubio, M; Carrión Campo, R; Moya Moya, M A; Rico Sergado, L

    2017-03-01

    A 43-year-old woman in remission from T- cell acute lymphoblastic leukaemia was referred to our hospital with suspected leukaemic retinitis. The funduscopic examination of her left eye revealed multifocal yellow-white peripheral retinitis and retinal haemorrhage. The patient was treated for cytomegalovirus retinitis after an extended haematological investigation showed no abnormalities. Initial improvement was followed by papillitis in the left eye and motility restriction in the right eye. Magnetic resonance and lumbar puncture confirmed leukaemia relapse. Specific treatment was initiated with complete resolution. Ocular involvement may precede haematological leukaemia relapse. Physicians should be alerted when ocular symptoms appear in these cases. Copyright © 2016 Sociedad Española de Oftalmología. Publicado por Elsevier España, S.L.U. All rights reserved.

  2. ZFAT plays critical roles in peripheral T cell homeostasis and its T cell receptor-mediated response

    International Nuclear Information System (INIS)

    Doi, Keiko; Fujimoto, Takahiro; Okamura, Tadashi; Ogawa, Masahiro; Tanaka, Yoko; Mototani, Yasumasa; Goto, Motohito; Ota, Takeharu; Matsuzaki, Hiroshi; Kuroki, Masahide; Tsunoda, Toshiyuki; Sasazuki, Takehiko; Shirasawa, Senji

    2012-01-01

    Highlights: ► We generated Cd4-Cre-mediated T cell-specific Zfat-deficient mice. ► Zfat-deficiency leads to reduction in the number of the peripheral T cells. ► Impaired T cell receptor-mediated response in Zfat-deficient peripheral T cells. ► Decreased expression of IL-7Rα, IL-2Rα and IL-2 in Zfat-deficient peripheral T cells. ► Zfat plays critical roles in peripheral T cell homeostasis. -- Abstract: ZFAT, originally identified as a candidate susceptibility gene for autoimmune thyroid disease, has been reported to be involved in apoptosis, development and primitive hematopoiesis. Zfat is highly expressed in T- and B-cells in the lymphoid tissues, however, its physiological function in the immune system remains totally unknown. Here, we generated the T cell-specific Zfat-deficient mice and demonstrated that Zfat-deficiency leads to a remarkable reduction in the number of the peripheral T cells. Intriguingly, a reduced expression of IL-7Rα and the impaired responsiveness to IL-7 for the survival were observed in the Zfat-deficient T cells. Furthermore, a severe defect in proliferation and increased apoptosis in the Zfat-deficient T cells following T cell receptor (TCR) stimulation was observed with a reduced IL-2Rα expression as well as a reduced IL-2 production. Thus, our findings reveal that Zfat is a critical regulator in peripheral T cell homeostasis and its TCR-mediated response.

  3. T cell activation and proliferation following acute exercise in human subjects is altered by storage conditions and mitogen selection.

    Science.gov (United States)

    Siedlik, Jacob A; Deckert, Jake A; Benedict, Stephen H; Bhatta, Anuja; Dunbar, Amanda J; Vardiman, John P; Gallagher, Philip M

    2017-07-01

    Recent work investigating exercise induced changes in immunocompetence suggests that some of the ambiguity in the literature is resultant from different cell isolation protocols and mitogen selection. To understand this effect, we compared post-exercise measures of T cell activation and proliferation using two different stimulation methods (costimulation through CD28 or stimulation with phytohaemagglutinin [PHA]). Further, we investigated whether exercise induced changes are maintained when T cell isolation from whole blood is delayed overnight in either a room temperature or chilled (4°C) environment. As expected, an increased proliferation response was observed post-exercise in T cells isolated from whole blood of previously trained individuals immediately after blood collection. Also, cells stimulated with PHA after resting overnight in whole blood were not adversely impacted by the storage conditions. In contrast, allowing cells to rest overnight in whole blood prior to stimulation through CD28, lessened the proliferation observed by cells following exercise rendering both the room temperature and chilled samples closer to the results seen in the control condition. Changes in early markers of activation (CD25), followed a similar pattern, with activation in PHA stimulated cells remaining fairly robust after overnight storage; whereas cell activation following stimulation through CD3+CD28 was disproportionately decreased by the influence of overnight storage. These findings indicate that decisions regarding cell stimulation methods need to be paired with the timeline for T cell isolation from whole blood. These considerations will be especially important for field based studies of immunocompetence where there is a delay in getting whole blood samples to a lab for processing as well as clinical applications where a failure to isolate T cells in a timely manner may result in loss of the response of interest. Copyright © 2017 Elsevier B.V. All rights reserved.

  4. Inhibition of cell proliferation and migration by oxidative stress from ascorbate-driven juglone redox cycling in human bladder-derived T24 cells

    Energy Technology Data Exchange (ETDEWEB)

    Kviecinski, M.R., E-mail: mrkviecinski@hotmail.com [Laboratorio de Bioquimica Experimental, Departamento de Bioquimica, Universidade Federal de Santa Catarina, Florianopolis (Brazil); Pedrosa, R.C., E-mail: rozangelapedrosa@gmail.com [Laboratorio de Bioquimica Experimental, Departamento de Bioquimica, Universidade Federal de Santa Catarina, Florianopolis (Brazil); Felipe, K.B., E-mail: kakabettega@yahoo.com.br [Laboratorio de Bioquimica Experimental, Departamento de Bioquimica, Universidade Federal de Santa Catarina, Florianopolis (Brazil); Farias, M.S., E-mail: mirellesfarias@hotmail.com [Laboratorio de Bioquimica Experimental, Departamento de Bioquimica, Universidade Federal de Santa Catarina, Florianopolis (Brazil); Glorieux, C., E-mail: christophe.glorieux@uclouvain.be [Toxicology and Cancer Biology Research Group, Louvain Drug Research Institute, Universite Catholique de Louvain, 73 Avenue E. Mounier, GTOX 7309, 1200 Brussels (Belgium); Valenzuela, M., E-mail: mavalenzuela@med.uchile.cl [Toxicology and Cancer Biology Research Group, Louvain Drug Research Institute, Universite Catholique de Louvain, 73 Avenue E. Mounier, GTOX 7309, 1200 Brussels (Belgium); Sid, B., E-mail: brice.sid@uclouvain.be [Toxicology and Cancer Biology Research Group, Louvain Drug Research Institute, Universite Catholique de Louvain, 73 Avenue E. Mounier, GTOX 7309, 1200 Brussels (Belgium); and others

    2012-05-04

    Highlights: Black-Right-Pointing-Pointer The cytotoxicity of juglone is markedly increased by ascorbate. Black-Right-Pointing-Pointer T24 cell death by oxidative stress is necrosis-like. Black-Right-Pointing-Pointer Redox cycling by juglone/ascorbate inhibits cell proliferation. Black-Right-Pointing-Pointer Cellular migration is impaired by juglone/ascorbate. -- Abstract: The effects of juglone on T24 cells were assessed in the presence and absence of ascorbate. The EC{sub 50} value for juglone at 24 h decreased from 28.5 {mu}M to 6.3 {mu}M in the presence of ascorbate. In juglone-treated cells, ascorbate increased ROS formation (4-fold) and depleted GSH (65%). N-acetylcysteine or catalase restricted the juglone/ascorbate-mediated effects, highlighting the role of oxidative stress in juglone cytotoxicity. Juglone alone or associated with ascorbate did not cause caspase-3 activation or PARP cleavage, suggesting necrosis-like cell death. DNA damage and the mild ER stress caused by juglone were both enhanced by ascorbate. In cells treated with juglone (1-5 {mu}M), a concentration-dependent decrease in cell proliferation was observed. Ascorbate did not impair cell proliferation but its association with juglone led to a clonogenic death state. The motility of ascorbate-treated cells was not affected. Juglone slightly restricted motility, but cells lost their ability to migrate most noticeably when treated with juglone plus ascorbate. We postulate that juglone kills cells by a necrosis-like mechanism inhibiting cell proliferation and the motility of T24 cells. These effects are enhanced in the presence of ascorbate.

  5. Kaposi's-sarcoma-associated-herpesvirus-activated dendritic cells promote HIV-1 trans-infection and suppress CD4{sup +} T cell proliferation

    Energy Technology Data Exchange (ETDEWEB)

    Liu, Wan; Qin, Yan; Bai, Lei [Key Laboratory of Molecular Virology and Immunology, Institute Pasteur of Shanghai, the Chinese Academy of Sciences, Shanghai (China); Graduate School of the Chinese Academy of Sciences, Beijing (China); Lan, Ke [Key Laboratory of Molecular Virology and Immunology, Institute Pasteur of Shanghai, the Chinese Academy of Sciences, Shanghai (China); Wang, Jian-Hua, E-mail: Jh_wang@sibs.ac.cn [Key Laboratory of Molecular Virology and Immunology, Institute Pasteur of Shanghai, the Chinese Academy of Sciences, Shanghai (China)

    2013-06-05

    Infection of Kaposi's sarcoma-associated herpesvirus (KSHV) is commonly occurred in AIDS patients. KSHV and HIV-1 act cooperatively in regulating infection with each other and in human carcinogenesis. Dendritic cells (DCs), as the pivotal cells in host immunity, may be modulated by both viruses, for immunoevasion and dissemination, therefore, the interaction between DCs and each virus has been a prior focus for pathogenesis elucidation. Here, we assessed the potential effect of KSHV on DC–HIV-1 interaction. We found that KSHV stimulation could promote maturation of monocyte-derived DCs (MDDCs) and impaired the ability of MDDCs to drive proliferation of resting CD4{sup +} T cells, demonstrating the immunosuppression induced by KSHV. More importantly, KSHV-stimulated MDDCs could capture more HIV-1 and efficiently transferred these infectious viruses to Hut/CCR5 T cell line. Our results reveal the novel modulation of DC-mediated HIV-1 dissemination by KSHV, and highlight the importance of studying DC–HIV-1 interaction to elucidate HIV/AIDS pathogenesis. - Highlights: ► KSHV impaired the ability of MDDCs to drive proliferation of resting CD4{sup +} T cells. ► KSHV stimulation matured MDDCs and enhanced HIV-1 endocytosis. ► KSHV stimulated MDDCs increased ICAM-1 expression and tighten contact with T cells. ► KSHV-stimulated MDDCs promoted HIV-1 trans-infection of CD4{sup +} T cells.

  6. Putative oncogene Brachyury (T) is essential to specify cell fate but dispensable for notochord progenitor proliferation and EMT.

    Science.gov (United States)

    Zhu, Jianjian; Kwan, Kin Ming; Mackem, Susan

    2016-04-05

    The transcription factor Brachyury (T) gene is expressed throughout primary mesoderm (primitive streak and notochord) during early embryonic development and has been strongly implicated in the genesis of chordoma, a sarcoma of notochord cell origin. Additionally, T expression has been found in and proposed to play a role in promoting epithelial-mesenchymal transition (EMT) in various other types of human tumors. However, the role of T in normal mammalian notochord development and function is still not well-understood. We have generated an inducible knockdown model to efficiently and selectively deplete T from notochord in mouse embryos. In combination with genetic lineage tracing, we show that T function is essential for maintaining notochord cell fate and function. Progenitors adopt predominantly a neural fate in the absence of T, consistent with an origin from a common chordoneural progenitor. However, T function is dispensable for progenitor cell survival, proliferation, and EMT, which has implications for the therapeutic targeting of T in chordoma and other cancers.

  7. Membrane-bound Dickkopf-1 in Foxp3+ regulatory T cells suppresses T-cell-mediated autoimmune colitis.

    Science.gov (United States)

    Chae, Wook-Jin; Park, Jong-Hyun; Henegariu, Octavian; Yilmaz, Saliha; Hao, Liming; Bothwell, Alfred L M

    2017-10-01

    Induction of tolerance is a key mechanism to maintain or to restore immunological homeostasis. Here we show that Foxp3 + regulatory T (Treg) cells use Dickkopf-1 (DKK-1) to regulate T-cell-mediated tolerance in the T-cell-mediated autoimmune colitis model. Treg cells from DKK-1 hypomorphic doubleridge mice failed to control CD4 + T-cell proliferation, resulting in CD4 T-cell-mediated autoimmune colitis. Thymus-derived Treg cells showed a robust expression of DKK-1 but not in naive or effector CD4 T cells. DKK-1 expression in Foxp3 + Treg cells was further increased upon T-cell receptor stimulation in vitro and in vivo. Interestingly, Foxp3 + Treg cells expressed DKK-1 in the cell membrane and the functional inhibition of DKK-1 using DKK-1 monoclonal antibody abrogated the suppressor function of Foxp3 + Treg cells. DKK-1 expression was dependent on de novo protein synthesis and regulated by the mitogen-activated protein kinase pathway but not by the canonical Wnt pathway. Taken together, our results highlight membrane-bound DKK-1 as a novel Treg-derived mediator to maintain immunological tolerance in T-cell-mediated autoimmune colitis. © 2017 The Authors. Immunology Published by John Wiley & Sons Ltd.

  8. Pathogenetic, Clinical, and Prognostic Features of Adult t(4;11(q21;q23/MLL-AF4 Positive B-Cell Acute Lymphoblastic Leukemia

    Directory of Open Access Journals (Sweden)

    F. Marchesi

    2011-01-01

    Full Text Available Translocation t(4;11(q21;q23 leading to formation of MLL-AF4 fusion gene is found in about 10% of newly diagnosed B-cell acute lymphoblastic leukemia (ALL in adult patients. Patients expressing this chromosomal aberration present typical biological, immunophenotypic, and clinical features. This form of leukemia is universally recognized as high-risk leukemia and treatment intensification with allogeneic hematopoietic stem cell transplantation (HSCT in first complete remission (CR could be a valid option to improve prognosis, but data obtained from the literature are controversial. In this review, we briefly describe pathogenetic, clinical, and prognostic characteristics of adult t(4;11(q21;q23/MLL-AF4 positive ALL and provide a review of the clinical outcome reported by the most important cooperative groups worldwide.

  9. CD4+CD62L+ Central Memory T Cells Can Be Converted to Foxp3+ T Cells

    Science.gov (United States)

    Zhang, Xiaolong; Chang Li, Xian; Xiao, Xiang; Sun, Rui; Tian, Zhigang; Wei, Haiming

    2013-01-01

    The peripheral Foxp3+ Treg pool consists of naturally arising Treg (nTreg) and adaptive Treg cells (iTreg). It is well known that naive CD4+ T cells can be readily converted to Foxp3+ iTreg in vitro, and memory CD4+ T cells are resistant to conversion. In this study, we investigated the induction of Foxp3+ T cells from various CD4+ T-cell subsets in human peripheral blood. Though naive CD4+ T cells were readily converted to Foxp3+ T cells with TGF-β and IL-2 treatment in vitro, such Foxp3+ T cells did not express the memory marker CD45RO as do Foxp3+ T cells induced in the peripheral blood of Hepatitis B Virus (HBV) patients. Interestingly, a subset of human memory CD4+ T cells, defined as CD62L+ central memory T cells, could be induced by TGF-β to differentiate into Foxp3+ T cells. It is well known that Foxp3+ T cells derived from human CD4+CD25- T cells in vitro are lack suppressive functions. Our data about the suppressive functions of CD4+CD62L+ central memory T cell-derived Foxp3+ T cells support this conception, and an epigenetic analysis of these cells showed a similar methylation pattern in the FOXP3 Treg-specific demethylated region as the naive CD4+ T cell-derived Foxp3+ T cells. But further research showed that mouse CD4+ central memory T cells also could be induced to differentiate into Foxp3+ T cells, such Foxp3+ T cells could suppress the proliferation of effector T cells. Thus, our study identified CD4+CD62L+ central memory T cells as a novel potential source of iTreg. PMID:24155942

  10. Kefir induces cell-cycle arrest and apoptosis in HTLV-1-negative malignant T-lymphocytes

    Science.gov (United States)

    Maalouf, Katia; Baydoun, Elias; Rizk, Sandra

    2011-01-01

    Background: Adult lymphoblastic leukemia (ALL) is a malignancy that occurs in white blood cells. The overall cure rate in children is 85%, whereas it is only 40% in adults. Kefir is an important probiotic that contains many bioactive ingredients, which give it unique health benefits. It has been shown to control several cellular types of cancer. Purpose: The present study investigates the effect of a cell-free fraction of kefir on CEM and Jurkat cells, which are human T-lymphotropic virus type I (HTLV-1)-negative malignant T-lymphocytes. Methods: Cells were incubated with different kefir concentrations. The cytotoxicity of the compound was evaluated by determining the percentage viability of cells. The effect of all the noncytotoxic concentrations of kefir on the proliferation of CEM and Jurkat cells was then assessed. The levels of transforming growth factor-alpha (TGF-α), transforming growth factor- beta1 (TGF-β1), matrix metalloproteinase-2 (MMP-2), and MMP-9 mRNA upon kefir treatment were then analyzed using reverse transcriptase polymerase chain reaction (RT-PCR). Finally, the growth inhibitory effects of kefir on cell-cycle progression/apoptosis were assessed by Cell Death Detection (ELISA) and flow cytometry. Results: The maximum cytotoxicity recorded after 48-hours treatment with 80 μg/μL kefir was only 42% and 39% in CEM and Jurkat cells, respectively. The percent reduction in proliferation was very significant, and was dose-, and time-dependent. In both cell lines, kefir exhibited its antiproliferative effect by downregulating TGF-α and upregulating TGF-β1 mRNA expression. Upon kefir treatment, a marked increase in cell-cycle distribution was noted in the preG1 phase of CEM and Jurkat cells, indicating the proapoptotic effect of kefir, which was further confirmed by Cell Death Detection ELISA. However, kefir did not affect the mRNA expression of metalloproteinases needed for the invasion of leukemic cell lines. Conclusion: In conclusion, kefir is

  11. Kefir induces cell-cycle arrest and apoptosis in HTLV-1-negative malignant T-lymphocytes

    International Nuclear Information System (INIS)

    Maalouf, Katia; Baydoun, Elias; Rizk, Sandra

    2011-01-01

    Adult lymphoblastic leukemia (ALL) is a malignancy that occurs in white blood cells. The overall cure rate in children is 85%, whereas it is only 40% in adults. Kefir is an important probiotic that contains many bioactive ingredients, which give it unique health benefits. It has been shown to control several cellular types of cancer. The present study investigates the effect of a cell-free fraction of kefir on CEM and Jurkat cells, which are human T-lymphotropic virus type I (HTLV-1)-negative malignant T-lymphocytes. Cells were incubated with different kefir concentrations. The cytotoxicity of the compound was evaluated by determining the percentage viability of cells. The effect of all the noncytotoxic concentrations of kefir on the proliferation of CEM and Jurkat cells was then assessed. The levels of transforming growth factor-alpha (TGF-α), transforming growth factor- beta1 (TGF-β1), matrix metalloproteinase-2 (MMP-2), and MMP-9 mRNA upon kefir treatment were then analyzed using reverse transcriptase polymerase chain reaction (RT-PCR). Finally, the growth inhibitory effects of kefir on cell-cycle progression/apoptosis were assessed by Cell Death Detection (ELISA) and flow cytometry. The maximum cytotoxicity recorded after 48-hours treatment with 80 μg/μL kefir was only 42% and 39% in CEM and Jurkat cells, respectively. The percent reduction in proliferation was very significant, and was dose-, and time-dependent. In both cell lines, kefir exhibited its antiproliferative effect by downregulating TGF-α and upregulating TGF-β1 mRNA expression. Upon kefir treatment, a marked increase in cell-cycle distribution was noted in the preG 1 phase of CEM and Jurkat cells, indicating the proapoptotic effect of kefir, which was further confirmed by Cell Death Detection ELISA. However, kefir did not affect the mRNA expression of metalloproteinases needed for the invasion of leukemic cell lines. In conclusion, kefir is effective in inhibiting proliferation and inducing

  12. [Regulatory B cells activated by CpG-ODN combined with anti-CD40 monoclonal antibody inhibit CD4(+)T cell proliferation].

    Science.gov (United States)

    Wang, Keng; Tao, Lei; Su, Jianbing; Zhang, Yueyang; Zou, Binhua; Wang, Yiyuan; Li, Xiaojuan

    2016-09-01

    Objective To observe the immunosuppressive function of regulatory B cells (Bregs) in vitro after activated by CpG oligodeoxynucleotide (CpG-ODN) and anti-CD40 mAb. Methods Mice splenic CD5(+)CD1d(high)B cells and CD5(-)CD1d(low)B cells were sorted by flow cytometry. These B cells were first stimulated with CpG-ODN combined with anti-CD40 mAb for 24 hours, and then co-cultured with purified CD4(+)T cells. The interleukin 10 (IL-10) expression in the activated Bregs and other B cell subset, as well as the proliferation and interferon γ (IFN-γ) expression in the CD4(+) T cells activated by anti-CD3 mAb plus anti-CD28 mAb were determined by flow cytometry. Results CD5(+)CD1d(high) B cells activated by CpG-ODN plus anti-CD40 mAb blocked the up-regulated CD4(+)T proliferation and significantly reduced the IFN-γ level. At the same time, activated CD5(-)CD1d(low)B cells showed no inhibitory effect on CD4(+)T cells. Further study revealed that IL-10 expression in the CD5(+)CD1d(high) B cells were much higher than that in the CD5(-)CD1d(low)B cells after stimulated with CpG-ODN combined with anti-CD40 mAb for 24 hours. Conclusion CD5(+)CD1d(high) B cells activated by CpG-ODN combined with anti-CD40 mAb have immune inhibitory effects on CD4(+)T cell activation in vitro , which possibly due to IL-10 secretion.

  13. Gap junctions at the dendritic cell-T cell interface are key elements for antigen-dependent T cell activation.

    Science.gov (United States)

    Elgueta, Raul; Tobar, Jaime A; Shoji, Kenji F; De Calisto, Jaime; Kalergis, Alexis M; Bono, Maria R; Rosemblatt, Mario; Sáez, Juan C

    2009-07-01

    The acquired immune response begins with Ag presentation by dendritic cells (DCs) to naive T cells in a heterocellular cell-cell contact-dependent process. Although both DCs and T cells are known to express connexin43, a gap junction protein subunit, the role of connexin43 on the initiation of T cell responses remains to be elucidated. In the present work, we report the formation of gap junctions between DCs and T cells and their role on T cell activation during Ag presentation by DCs. In cocultures of DCs and T cells, Lucifer yellow microinjected into DCs is transferred to adjacent transgenic CD4(+) T cells, only if the specific antigenic peptide was present at least during the first 24 h of cocultures. This dye transfer was sensitive to gap junction blockers, such as oleamide, and small peptides containing the extracellular loop sequences of conexin. Furthermore, in this system, gap junction blockers drastically reduced T cell activation as reflected by lower proliferation, CD69 expression, and IL-2 secretion. This lower T cell activation produced by gap junction blockers was not due to a lower expression of CD80, CD86, CD40, and MHC-II on DCs. Furthermore, gap junction blocker did not affect polyclonal activation of T cell induced with anti-CD3 plus anti-CD28 Abs in the absence of DCs. These results strongly suggest that functional gap junctions assemble at the interface between DCs and T cells during Ag presentation and that they play an essential role in T cell activation.

  14. TLX homeodomain oncogenes mediate T cell maturation arrest in T-ALL via interaction with ETS1 and suppression of TCRα gene expression.

    Science.gov (United States)

    Dadi, Saïda; Le Noir, Sandrine; Payet-Bornet, Dominique; Lhermitte, Ludovic; Zacarias-Cabeza, Joaquin; Bergeron, Julie; Villarèse, Patrick; Vachez, Elodie; Dik, Willem A; Millien, Corinne; Radford, Isabelle; Verhoeyen, Els; Cosset, François-Loïc; Petit, Arnaud; Ifrah, Norbert; Dombret, Hervé; Hermine, Olivier; Spicuglia, Salvatore; Langerak, Anton W; Macintyre, Elizabeth A; Nadel, Bertrand; Ferrier, Pierre; Asnafi, Vahid

    2012-04-17

    Acute lymphoblastic leukemias (ALLs) are characterized by multistep oncogenic processes leading to cell-differentiation arrest and proliferation. Specific abrogation of maturation blockage constitutes a promising therapeutic option in cancer, which requires precise understanding of the underlying molecular mechanisms. We show that the cortical thymic maturation arrest in T-lineage ALLs that overexpress TLX1 or TLX3 is due to binding of TLX1/TLX3 to ETS1, leading to repression of T cell receptor (TCR) α enhanceosome activity and blocked TCR-Jα rearrangement. TLX1/TLX3 abrogation or enforced TCRαβ expression leads to TCRα rearrangement and apoptosis. Importantly, the autoextinction of clones carrying TCRα-driven TLX1 expression supports TLX "addiction" in TLX-positive leukemias and provides further rationale for targeted therapy based on disruption of TLX1/TLX3. Copyright © 2012 Elsevier Inc. All rights reserved.

  15. Molecular signature of cell cycle exit induced in human T lymphoblasts by IL-2 withdrawal

    Directory of Open Access Journals (Sweden)

    Pfeifer Aleksandra

    2009-06-01

    Full Text Available Abstract Background The molecular mechanisms of cell cycle exit are poorly understood. Studies on lymphocytes at cell cycle exit after growth factor deprivation have predominantly focused on the initiation of apoptosis. We aimed to study gene expression profile of primary and immortalised IL-2-dependent human T cells forced to exit the cell cycle by growth factor withdrawal, before apoptosis could be evidenced. Results By the Affymetrix microarrays HG-U133 2.0 Plus, 53 genes were distinguished as differentially expressed before and soon after IL-2 deprivation. Among those, PIM1, BCL2, IL-8, HBEGF, DUSP6, OSM, CISH, SOCS2, SOCS3, LIF and IL13 were down-regulated and RPS24, SQSTM1, TMEM1, LRRC8D, ECOP, YY1AP1, C1orf63, ASAH1, SLC25A46 and MIA3 were up-regulated. Genes linked to transcription, cell cycle, cell growth, proliferation and differentiation, cell adhesion, and immune functions were found to be overrepresented within the set of the differentially expressed genes. Conclusion Cell cycle exit of the growth factor-deprived T lymphocytes is characterised by a signature of differentially expressed genes. A coordinate repression of a set of genes known to be induced during T cell activation is observed. However, growth arrest following exit from the cell cycle is actively controlled by several up-regulated genes that enforce the non-dividing state. The identification of genes involved in cell cycle exit and quiescence provides new hints for further studies on the molecular mechanisms regulating the non-dividing state of a cell, the mechanisms closely related to cancer development and to many biological processes.

  16. ZFAT plays critical roles in peripheral T cell homeostasis and its T cell receptor-mediated response

    Energy Technology Data Exchange (ETDEWEB)

    Doi, Keiko [Department of Cell Biology, Faculty of Medicine, Fukuoka University, Fukuoka (Japan); Central Research Institute for Advanced Molecular Medicine, Fukuoka University, Fukuoka (Japan); Central Research Institute of Life Sciences for the Next Generation of Women Scientists, Fukuoka University, Fukuoka (Japan); Fujimoto, Takahiro [Department of Cell Biology, Faculty of Medicine, Fukuoka University, Fukuoka (Japan); Central Research Institute for Advanced Molecular Medicine, Fukuoka University, Fukuoka (Japan); Okamura, Tadashi [Division of Animal Models, Department of Infectious Diseases, Research Institute, National Center for Global Health and Medicine, Tokyo (Japan); Ogawa, Masahiro [Central Research Institute for Advanced Molecular Medicine, Fukuoka University, Fukuoka (Japan); Tanaka, Yoko [Department of Cell Biology, Faculty of Medicine, Fukuoka University, Fukuoka (Japan); Mototani, Yasumasa; Goto, Motohito [Division of Animal Models, Department of Infectious Diseases, Research Institute, National Center for Global Health and Medicine, Tokyo (Japan); Ota, Takeharu; Matsuzaki, Hiroshi [Department of Cell Biology, Faculty of Medicine, Fukuoka University, Fukuoka (Japan); Kuroki, Masahide [Central Research Institute for Advanced Molecular Medicine, Fukuoka University, Fukuoka (Japan); Tsunoda, Toshiyuki [Department of Cell Biology, Faculty of Medicine, Fukuoka University, Fukuoka (Japan); Central Research Institute for Advanced Molecular Medicine, Fukuoka University, Fukuoka (Japan); Sasazuki, Takehiko [Institute for Advanced Study, Kyushu University, Fukuoka (Japan); Shirasawa, Senji, E-mail: sshirasa@fukuoka-u.ac.jp [Department of Cell Biology, Faculty of Medicine, Fukuoka University, Fukuoka (Japan); Central Research Institute for Advanced Molecular Medicine, Fukuoka University, Fukuoka (Japan)

    2012-08-17

    Highlights: Black-Right-Pointing-Pointer We generated Cd4-Cre-mediated T cell-specific Zfat-deficient mice. Black-Right-Pointing-Pointer Zfat-deficiency leads to reduction in the number of the peripheral T cells. Black-Right-Pointing-Pointer Impaired T cell receptor-mediated response in Zfat-deficient peripheral T cells. Black-Right-Pointing-Pointer Decreased expression of IL-7R{alpha}, IL-2R{alpha} and IL-2 in Zfat-deficient peripheral T cells. Black-Right-Pointing-Pointer Zfat plays critical roles in peripheral T cell homeostasis. -- Abstract: ZFAT, originally identified as a candidate susceptibility gene for autoimmune thyroid disease, has been reported to be involved in apoptosis, development and primitive hematopoiesis. Zfat is highly expressed in T- and B-cells in the lymphoid tissues, however, its physiological function in the immune system remains totally unknown. Here, we generated the T cell-specific Zfat-deficient mice and demonstrated that Zfat-deficiency leads to a remarkable reduction in the number of the peripheral T cells. Intriguingly, a reduced expression of IL-7R{alpha} and the impaired responsiveness to IL-7 for the survival were observed in the Zfat-deficient T cells. Furthermore, a severe defect in proliferation and increased apoptosis in the Zfat-deficient T cells following T cell receptor (TCR) stimulation was observed with a reduced IL-2R{alpha} expression as well as a reduced IL-2 production. Thus, our findings reveal that Zfat is a critical regulator in peripheral T cell homeostasis and its TCR-mediated response.

  17. Functional and genomic analyses of FOXP3-transduced Jurkat-T cells as regulatory T (Treg)-like cells

    International Nuclear Information System (INIS)

    Kim, Joon-Young; Kim, Han-Jong; Hurt, Elaine M.; Chen, Xin; Howard, O.M. Zack; Farrar, William L.

    2007-01-01

    FOXP3, a forkhead transcription factor is essential for the development and function of CD4 + CD25 + regulatory T cells (Tregs). In contrast to conversion of murine naive T cells to Tregs by transduction of Foxp3, it is controversial whether ectopic expression of FOXP3 in human CD4 + T cells is sufficient for acquisition of suppressive activity. Here, we show that retroviral transduction of FOXP3 induces a Treg phenotype in human leukemic CD4 + Jurkat-T cells, evidenced by increased expression of Treg-associated cell surface markers as well as inhibition of cytokine production. Furthermore, FOXP3-transduced Jurkat-T cells suppress the proliferation of human CD4 + CD25 - T cells. Additionally, DNA microarray analysis identifies Treg-related genes regulated by FOXP3. Our study demonstrates that enforced expression of FOXP3 confers Treg-like properties on Jurkat-T cells, which can be a convenient and efficient Treg-like cell model for further study to identify Treg cell surface markers and target genes regulated by FOXP3

  18. Effect of sirolimus on urinary bladder cancer T24 cell line

    Directory of Open Access Journals (Sweden)

    Oliveira Paula A

    2009-01-01

    Full Text Available Abstract Background Sirolimus is recently reported to have antitumour effects on a large variety of cancers. The present study was performed to investigate sirolimus's ability to inhibit growth in T24 bladder cancer cells. Methods T24 bladder cancer cells were treated with various concentrations of sirolimus. MTT assay was used to evaluate the proliferation inhibitory effect on T24 cell line. The viability of T24 cell line was determined by Trypan blue exclusion analysis. Results Sirolimus inhibits the growth of bladder carcinoma cells and decreases their viability. Significant correlations were found between cell proliferation and sirolimus concentration (r = 0.830; p Conclusion Sirolimus has an anti-proliferation effect on the T24 bladder carcinoma cell line. The information from our results is useful for a better understanding sirolimus's anti-proliferative activity in the T24 bladder cancer cell line.

  19. Chimeric Antigen Receptor (CAR) T cells: Lessons Learned from Targeting of CD19 in B cell malignancies

    Science.gov (United States)

    Hay, Kevin A; Turtle, Cameron J

    2017-01-01

    Adoptive immunotherapy with chimeric antigen receptor-modified T (CAR-T) cells is a rapidly growing therapeutic approach to treating patients with refractory cancer, with over 100 clinical trials in various malignancies in progress. The enthusiasm for CAR-T cells has been driven by the clinical success of CD19-targeted CAR-T therapy in B-cell acute lymphoblastic leukemia, and the promising data in B-cell non-Hodgkin’s lymphoma and chronic lymphocytic leukemia. Despite the success of targeting CD19 with CAR-T cells in early clinical studies, many challenges remain to improve outcomes, reduce toxicity, and determine the appropriate settings for CAR-T cell immunotherapy. Reviewing the lessons learned thus far in CD19 CAR-T cell trials and how some of these challenges may be overcome will help guide the development of CAR-T cell therapy for malignancies of B-cell origin, as well as for other hematopoietic and non-hematopoietic cancers. PMID:28110394

  20. Differential Activity of Voltage- and Ca2+-Dependent Potassium Channels in Leukemic T Cell Lines: Jurkat Cells Represent an Exceptional Case

    Directory of Open Access Journals (Sweden)

    Salvador Valle-Reyes

    2018-05-01

    Full Text Available Activation of resting T cells relies on sustained Ca2+ influx across the plasma membrane, which in turn depends on the functional expression of potassium channels, whose activity repolarizes the membrane potential. Depending on the T-cells subset, upon activation the expression of Ca2+- or voltage-activated K+ channels, KCa or Kv, is up-regulated. In this study, by means of patch-clamp technique in the whole cell mode, we have studied in detail the characteristics of Kv and KCa currents in resting and activated human T cells, the only well explored human T-leukemic cell line Jurkat, and two additional human leukemic T cell lines, CEM and MOLT-3. Voltage dependence of activation and inactivation of Kv1.3 current were shifted up to by 15 mV to more negative potentials upon a prolonged incubation in the whole cell mode and displayed little difference at a stable state in all cell lines but CEM, where the activation curve was biphasic, with a high and low potential components. In Jurkat, KCa currents were dominated by apamine-sensitive KCa2.2 channels, whereas only KCa3.1 current was detected in healthy T and leukemic CEM and MOLT-3 cells. Despite a high proliferation potential of Jurkat cells, Kv and KCa currents were unexpectedly small, more than 10-fold lesser as compared to activated healthy human T cells, CEM and MOLT-3, which displayed characteristic Kv1.3high:KCa3.1high phenotype. Our results suggest that Jurkat cells represent perhaps a singular case and call for more extensive studies on primary leukemic T cell lines as well as a verification of the therapeutic potential of specific KCa3.1 blockers to combat acute lymphoblastic T leukemias.

  1. Inhibition of primary human T cell proliferation by Helicobacter pylori vacuolating toxin (VacA) is independent of VacA effects on IL-2 secretion

    OpenAIRE

    Sundrud, Mark S.; Torres, Victor J.; Unutmaz, Derya; Cover, Timothy L.

    2004-01-01

    Recent evidence indicates that the secreted Helicobacter pylori vacuolating toxin (VacA) inhibits the activation of T cells. VacA blocks IL-2 secretion in transformed T cell lines by suppressing the activation of nuclear factor of activated T cells (NFAT). In this study, we investigated the effects of VacA on primary human CD4+ T cells. VacA inhibited the proliferation of primary human T cells activated through the T cell receptor (TCR) and CD28. VacA-treated Jurkat T cells secreted markedly ...

  2. Epigenetic inactivation of TWIST2 in acute lymphoblastic leukemia modulates proliferation, cell survival and chemosensitivity

    Science.gov (United States)

    Thathia, Shabnam H.; Ferguson, Stuart; Gautrey, Hannah E.; van Otterdijk, Sanne D.; Hili, Michela; Rand, Vikki; Moorman, Anthony V.; Meyer, Stefan; Brown, Robert; Strathdee, Gordon

    2012-01-01

    Background Altered regulation of many transcription factors has been shown to be important in the development of leukemia. TWIST2 modulates the activity of a number of important transcription factors and is known to be a regulator of hematopoietic differentiation. Here, we investigated the significance of epigenetic regulation of TWIST2 in the control of cell growth and survival and in response to cytotoxic agents in acute lymphoblastic leukemia. Design and Methods TWIST2 promoter methylation status was assessed quantitatively, by combined bisulfite and restriction analysis (COBRA) and pyrosequencing assays, in multiple types of leukemia and TWIST2 expression was determined by quantitative reverse transcriptase polymerase chain reaction analysis. The functional role of TWIST2 in cell proliferation, survival and response to chemotherapy was assessed in transient and stable expression systems. Results We found that TWIST2 was inactivated in more than 50% of cases of childhood and adult acute lymphoblastic leukemia through promoter hypermethylation and that this epigenetic regulation was especially prevalent in RUNX1-ETV6-driven cases. Re-expression of TWIST2 in cell lines resulted in a dramatic reduction in cell growth and induction of apoptosis in the Reh cell line. Furthermore, re-expression of TWIST2 resulted in increased sensitivity to the chemotherapeutic agents etoposide, daunorubicin and dexamethasone and TWIST2 hypermethylation was almost invariably found in relapsed adult acute lymphoblastic leukemia (91% of samples hypermethylated). Conclusions This study suggests a dual role for epigenetic inactivation of TWIST2 in acute lymphoblastic leukemia, initially through altering cell growth and survival properties and subsequently by increasing resistance to chemotherapy. PMID:22058208

  3. T cell suppression by naturally occurring HLA-G-expressing regulatory CD4+ T cells is IL-10-dependent and reversible.

    Science.gov (United States)

    Huang, Yu-Hwa; Zozulya, Alla L; Weidenfeller, Christian; Schwab, Nicholas; Wiendl, Heinz

    2009-08-01

    CD4(+) T cells constitutively expressing the immune-tolerogenic HLA-G have been described recently as a new type of nT(reg) (HLA-G(pos) T(reg)) in humans. HLA-G(pos) T(reg) accumulate at sites of inflammation and are potent suppressors of T cell proliferation in vitro, suggesting their role in immune regulation. We here characterize the mechanism of how CD4(+) HLA-G(pos) T(reg) influence autologous HLA-G(neg) T(resp) function. Using a suppression system free of APC, we demonstrate a T-T cell interaction, resulting in suppression of HLA-G(neg) T(resp), which is facilitated by TCR engagement on HLA-G(pos) T(reg). Suppression is independent of cell-cell contact and is reversible, as the removal of HLA-G(pos) T(reg) from the established coculture restored the proliferative capability of responder cells. Further, HLA-G(pos) T(reg)-mediated suppression critically depends on the secretion of IL-10 but not TGF-beta.

  4. Immunobiology of T cell responses to Mls-locus-disparate stimulator cells. III. Helper and cytolytic functions of cloned, Mls-reactive T cell lines

    International Nuclear Information System (INIS)

    Katz, M.E.; Tite, J.P.; Janeway, C.A. Jr.

    1986-01-01

    Mls-specific T cell clones derived by limiting dilution were tested for cytotoxic activity in a lectin-dependent 51 Cr-release assay. All the T cell clones tested were cytotoxic in such an assay in apparent contrast to previous reports (1, 2). However, only those target cells sensitive to cytolysis by other L3T4a + cytolytic T cells (3) were killed by Mls-specific T cell clones in short term 51 Cr-release assays, possibly explaining this discrepancy. All the T cell clones tested were L3T4a + ,Lyt-2 - and stimulated B cells from Mls strains of mice to proliferate and secrete immunoglobulin. Furthermore, lysis of innocent bystander targets was observed when the T cells were stimulated with Mls-disparate stimulator cells. These results are consistent with those obtained with L3T4a - T cells specific for protein antigen:self Ia and that express cytotoxic potential (3)

  5. Ageing combines CD4 T cell lymphopenia in secondary lymphoid organs and T cell accumulation in gut associated lymphoid tissue.

    Science.gov (United States)

    Martinet, Kim Zita; Bloquet, Stéphane; Bourgeois, Christine

    2014-01-01

    CD4 T cell lymphopenia is an important T cell defect associated to ageing. Higher susceptibility to infections, cancer, or autoimmune pathologies described in aged individuals is thought to partly rely on T cell lymphopenia. We hypothesize that such diverse effects may reflect anatomical heterogeneity of age related T cell lymphopenia. Indeed, no data are currently available on the impact of ageing on T cell pool recovered from gut associated lymphoid tissue (GALT), a crucial site of CD4 T cell accumulation. Primary, secondary and tertiary lymphoid organs of C57BL/6 animals were analysed at three intervals of ages: 2 to 6 months (young), 10 to 14 months (middle-aged) and 22 to 26 months (old). We confirmed that ageing preferentially impacted CD4 T cell compartment in secondary lymphoid organs. Importantly, a different picture emerged from gut associated mucosal sites: during ageing, CD4 T cell accumulation was progressively developing in colon and small intestine lamina propria and Peyer's patches. Similar trend was also observed in middle-aged SJL/B6 F1 mice. Interestingly, an inverse correlation was detected between CD4 T cell numbers in secondary lymphoid organs and colonic lamina propria of C57BL/6 mice whereas no increase in proliferation rate of GALT CD4 T cells was detected. In contrast to GALT, no CD4 T cell accumulation was detected in lungs and liver in middle-aged animals. Finally, the concomitant accumulation of CD4 T cell in GALT and depletion in secondary lymphoid organs during ageing was detected both in male and female animals. Our data thus demonstrate that T cell lymphopenia in secondary lymphoid organs currently associated to ageing is not sustained in gut or lung mucosa associated lymphoid tissues or non-lymphoid sites such as the liver. The inverse correlation between CD4 T cell numbers in secondary lymphoid organs and colonic lamina propria and the absence of overt proliferation in GALT suggest that marked CD4 T cell decay in secondary

  6. Chimeric Antigen Receptor (CAR) T Cells: Lessons Learned from Targeting of CD19 in B-Cell Malignancies.

    Science.gov (United States)

    Hay, Kevin A; Turtle, Cameron J

    2017-03-01

    Adoptive immunotherapy with chimeric antigen receptor-modified (CAR)-T cells is a rapidly growing therapeutic approach to treating patients with refractory cancer, with over 100 clinical trials in various malignancies in progress. The enthusiasm for CAR-T cells has been driven by the clinical success of CD19-targeted CAR-T cell therapy in B-cell acute lymphoblastic leukemia, and the promising data in B-cell non-Hodgkin's lymphoma and chronic lymphocytic leukemia. Despite the success of targeting CD19 with CAR-T cells in early clinical studies, many challenges remain to improve outcomes, reduce toxicity, and determine the appropriate settings for CAR-T cell immunotherapy. Reviewing the lessons learned thus far in CD19 CAR-T cell trials and how some of these challenges may be overcome will help guide the development of CAR-T cell therapy for malignancies of B-cell origin, as well as for other hematopoietic and non-hematopoietic cancers.

  7. Distinctive in vitro effects of T-cell growth cytokines on cytomegalovirus-stimulated T-cell responses of HIV-infected HAART recipients

    International Nuclear Information System (INIS)

    Patterson, Julie; Jesser, Renee; Weinberg, Adriana

    2008-01-01

    Functional immune reconstitution is limited after HAART, maintaining the interest in adjunctive immune-modulators. We compared in vitro the effects of the γ-chain T-cell growth cytokines IL-2, IL-4, IL-7 and IL-15 on cytomegalovirus-stimulated cell-mediated immunity. IL-2 and IL-15 increased cytomegalovirus-specific lymphocyte proliferation in HAART recipients, whereas IL-4 and IL-7 did not. The boosting effect of IL-2 and IL-15 on proliferation correlated with their ability to prevent late apoptosis. However, IL-2 increased the frequency of cells in early apoptosis, whereas IL-15 increased the frequency of fully viable cells. Both IL-2 and IL-15 increased cytomegalovirus-induced CD4 + and CD8 + T-cell proliferation and the synthesis of Th1 and pro-inflammatory cytokines and chemokines. However, only IL-2 increased the frequency of regulatory T cells and Th2 cytokine production, both of which have the potential to attenuate antiviral immune responses. Overall, compared to other γ-chain cytokines, IL-15 had the most favorable profile for boosting antiviral cell-mediated immunity

  8. Role of signaling lymphocytic activation molecule in T helper cell responses

    Directory of Open Access Journals (Sweden)

    Jan E. de Vries

    1998-01-01

    Full Text Available Signaling lymphocytic activation molecule (SLAM; CDw150 is a 70 kDa glycoprotein. Signaling lymphocytic activation molecule is constitutively expressed on memory T cells, CD56+ T cells, a subset of T cell receptor γδ+ cells, immature thymocytes and, at low levels, on a proportion of peripheral blood B cells. Signaling lymphocytic activation molecule is rapidly upregulated on all T and B cells after activation. Engagement of SLAM by F(ab’2 fragments of an anti-SLAM monoclonal antibody (mAb A12 enhances antigen-specific T cell proliferation. In addition, mAb A12 was directly mitogenic for T cell clones and activated T cells. T cell proliferation induced by mAb A12 is independent of interleukin (IL-2, IL-4, IL-12 and IL-15, but is cyclosporin A sensitive. Ligation of SLAM during antigen-specific T cell proliferation resulted in upregulation of interferon (IFN-γ production, even by allergen-specific T helper cell (Th 2 clones, whereas the levels of IL-4 and IL-5 production were only marginally affected. The mAb A12 was unable to induce IL-4 and IL-5 production by Th1 clones. Co-stimulation of skin-derived Der P1-specific Th2 cells from patients with atopic dermatitis via SLAM resulted in the generation of a population of IFN-γ-producing cells, thereby reverting their phenotype to a Th0 pattern. Signaling lymphocytic activation molecule is a high-affinity self ligand mediating homophilic cell interaction. In addition, soluble SLAM enhances both T and B cell proliferation. Collectively, these data indicate that SLAM molecules act both as receptors and ligands that are not only involved in T cell expansion but also drive the expanding T cells during immune responses into the Th0/Th1 pathway. This suggests that signaling through SLAM plays a role in directing Th0/Th1 development.

  9. Zizyphus lotus L. (Desf. modulates antioxidant activity and human T-cell proliferation

    Directory of Open Access Journals (Sweden)

    Belarbi Meriem

    2010-09-01

    Full Text Available Abstract Background Zizyphus lotus L. (Desf. also known as Jujube, is a deciduous shrub which belongs to Rhamnaceae family. This plant is used in Algerian traditional medicine for its anti-diabetic, sedative, analgesic, anti-inflammatory and hypoglycaemic activities. In the present study, we determined the concentrations of different vitamins (vitamin A, C and E and fatty acids in root, stem, leaves, fruit pulp and seed of Zizyphus lotus L. (Desf. and assessed the effects of their aqueous extracts on antioxidant status and human T-cell proliferation. Methods Aqueous filtrates from different parts, i.e, root, leaf, stem, fruit pulp and seed, of Zizyphus lotus L. (Desf. were prepared. Vitamin C levels were determined by precipitating with 10% trichloroacetic acid and vitamin A and E were assessed by HPLC. Lipid composition of these extracts was determined by gas-liquid chromatography. Anti-oxidant capacity was evaluated by using anti-radical resistance kit [Kit Radicaux Libres (KRL@; Kirial International SA, Couternon, France]. T-cell blastogenesis was assessed by the incorporation of 3H-thymidine. IL-2 gene expression was evaluated by RT-qPCR. Results Our results show that fruit pulp contained higher vitamin A and C contents than other parts of the plant. Furthermore, the fruit pulp was the richest source of linoleic acid (18:2n-6, a precursor of n-6 fatty acids. Fruit seeds possessed higher vitamin C levels than leaves, roots and stem. The leaves were the richest source of vitamin E and linolenic acid (18:3n-3, a precursor of n-3 fatty acids. The antioxidant capacity of the different extracts, measured by KRL@ test, was as follows: pulp Zizyphus lotus L. (Desf. exerted immunosuppressive effects. Conclusion Seed extracts exerted the most potent immunosuppressive effects on T cell proliferation and IL-2 mRNA expression. The results of the present study are discussed in the light of their use to modulate the immune-mediated diseases.

  10. Effects of vitamin K3 and K5 on proliferation, cytokine production, and regulatory T cell-frequency in human peripheral-blood mononuclear cells.

    Science.gov (United States)

    Hatanaka, Hiroshige; Ishizawa, Hitomi; Nakamura, Yurie; Tadokoro, Hiroko; Tanaka, Sachiko; Onda, Kenji; Sugiyama, Kentaro; Hirano, Toshihiko

    2014-03-18

    The effects of vitamin K (VK) derivatives VK3 and VK5 on human immune cells have not been extensively investigated. We examined the effects of VK3 and VK5 on proliferation, apoptosis, cytokine production, and CD4+CD25+Foxp3+ regulatory T (Treg) cell-frequency in human peripheral blood mononuclear cells (PBMCs) activated by T cell mitogen in vitro. Anti-proliferative effects of VK3 and VK5 on T-cell mitogen activated PBMCs were assessed by WST assay procedures. Apoptotic cells were determined as Annexin V positive/propidium iodide (PI) negative cells. Cytokine concentrations in the supernatant of the culture medium were measured with bead-array procedures followed by analysis with flow cytometry. The CD4+CD25+Foxp3+Treg cells in mitogen-activated PBMCs were stained with fluorescence-labeled specific antibodies followed by flow cytometry. VK3 and VK5 suppressed the mitogen-activated proliferation of PBMCs significantly at 10-100μM (p<0.05). The data also suggest that VK3 and VK5 promote apoptosis in the mitogen-activated T cells. VK3 and VK5 significantly inhibited the production of tumor necrosis factor (TNF) α, interleukin (IL)-4, -6, and -10 from the activated PBMCs at 10-100μM (p<0.05). In contrast, VK3 and VK5 significantly increased Treg cell-frequency in the activated PBMCs at concentrations more than 10μM (p<0.001). Our data suggest that VK3 and VK5 attenuate T cell mediated immunity by inhibiting the proliferative response and inducing apoptosis in activated T cells. Copyright © 2014 Elsevier Inc. All rights reserved.

  11. Human CD4+ T cells require exogenous cystine for glutathione and DNA synthesis

    DEFF Research Database (Denmark)

    Levring, Trine B; Kongsbak-Wismann, Martin; Rode, Anna Kathrine Obelitz

    2015-01-01

    . The aim of this study was to elucidate why activated human T cells require exogenous Cys2 in order to proliferate. We activated purified naïve human CD4+ T cells and found that glutathione (GSH) levels and DNA synthesis were dependent on Cys2 and increased in parallel with increasing concentrations of Cys......Adaptive immune responses require activation and expansion of antigen-specific T cells. Whereas early T cell activation is independent of exogenous cystine (Cys2), T cell proliferation is dependent of Cys2. However, the exact roles of Cys2 in T cell proliferation still need to be determined...... for the activity of ribonucleotide reductase (RNR), the enzyme responsible for generation of the deoxyribonucleotide DNA building blocks. In conclusion, we show that activated human T cells require exogenous Cys2 to proliferate and that this is partly explained by the fact that Cys2 is required for production...

  12. Metformin inhibits proliferation and cytotoxicity and induces apoptosis via AMPK pathway in CD19-chimeric antigen receptor-modified T cells

    Directory of Open Access Journals (Sweden)

    Mu Q

    2018-04-01

    Full Text Available Qian Mu,1,2,* Miao Jiang,1,* Yuzhu Zhang,1 Fei Wu,1 Hui Li,1 Wen Zhang,1 Fang Wang,1 Jiang Liu,1 Liang Li,1 Dongshan Wang,3 Wenjuan Wang,1 Shiwu Li,1 Haibo Song,4 Dongqi Tang1 1Gene and Immunotherapy Center, The Second Hospital of Shandong University, Jinan, People’s Republic of China; 2Department of Endocrinology and Metabolism, Ruijin Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai, People’s Republic of China; 3Health Management Center, The Second Hospital of Shandong University, Jinan, People’s Republic of China; 4Central Research Laboratory, Zibo Maternal and Child Health Hospital, Affiliated to Shandong Academy of Medical Science, Zibo, People’s Republic of China *These authors contributed equally to this work Background: CD19-chimericantigen receptor (CAR modified T cells (CD19-CAR T cells have been well documented to possess potent anti-tumor properties against CD19-expressingleukemia cells. As a traditional medicine, metformin has been widely used to treat type II diabetes mellitus and more recently has become a candidate for the treatment of cancer. However, no report has revealed the direct effect of metformin on CD19-CAR T cell biological function and its underling mechanisms. Purpose: The purpose of this research was to explore the effect of metformin on CD19-CAR T cell biological function and the mechanisms involved. Methods: CD19-CAR T cells proliferation, apoptosis and cytotoxicity were mainly tested by CCK-8 assay, flow cytometry and ELISA. The detection of mechanism primarily used western blot. Bioluminescence imaging is the main application technology of animal studies. Results: In the current study, it was found that metformin inhibited CD19-CAR T cell proliferation and cytotoxicity and induced apoptosis. Furthermore, our study revealed that metformin activated AMPK and suppressed mTOR and HIF1α expression. By using an AMPK inhibitor, compound C, we demonstrated the crucial roles of AMPK in CD19

  13. Chimeric Antigen Receptors T Cell Therapy in Solid Tumor: Challenges and Clinical Applications

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    Hamid R. Mirzaei

    2017-12-01

    Full Text Available Adoptive cellular immunotherapy (ACT employing engineered T lymphocytes expressing chimeric antigen receptors (CARs has demonstrated promising antitumor effects in advanced hematologic cancers, such as relapsed or refractory acute lymphoblastic leukemia, chronic lymphocytic leukemia, and non-Hodgkin lymphoma, supporting the translation of ACT to non-hematological malignancies. Although CAR T cell therapy has made remarkable strides in the treatment of patients with certain hematological cancers, in solid tumors success has been limited likely due to heterogeneous antigen expression, immunosuppressive networks in the tumor microenvironment limiting CAR T cell function and persistence, and suboptimal trafficking to solid tumors. Here, we outline specific approaches to overcome barriers to CAR T cell effectiveness in the context of the tumor microenvironment and offer our perspective on how expanding the use of CAR T cells in solid tumors may require modifications in CAR T cell design. We anticipate these modifications will further expand CAR T cell therapy in clinical practice.

  14. NF-κB is involved in the LPS-mediated proliferation and apoptosis of MAC-T epithelial cells as part of the subacute ruminal acidosis response in cows.

    Science.gov (United States)

    Fan, Wen-Jie; Li, He-Ping; Zhu, He-Shui; Sui, Shi-Ping; Chen, Pei-Ge; Deng, Yue; Sui, Tong-Ming; Wang, Yue-Ying

    2016-11-01

    To determine the effect of NF-κB on cell proliferation and apoptosis, we investigate the expression of inflammation and apoptosis-related factors in the bovine mammary epithelial cell line, MAC-T. MAC-T cells were cultured in vitro and MTT and LDH assays used to determine the effects of lipopolysaccharide (LPS) on proliferation and cytotoxicity respectively. RT-PCR and western blotting were used to evaluate the effect of LPS and NF-κB inhibition [pyrrolidine dithiocarbamate (PDTC) treatment] on the expression of inflammation and apoptosis-related factors. LPS significantly inhibited MAC-T cell proliferation in a dose- and time-dependent manner. Furthermore, LPS promoted apoptosis while the NF-кB inhibitor PDTC attenuated this effect. After LPS treatment, the NF-кB signaling pathway was activated, and the expression of inflammation and apoptosis-related factors increased. When PDTC blocked NF-кB signaling, the expression of inflammation and apoptosis-related factors were decreased in MAC-T cells. LPS activates the TLR4/NF-κB signaling pathway, inhibits proliferation and promotes apoptosis in MAC-T cells. NF-кB inhibition attenuates MAC-T cell apoptosis and TLR4/NF-κB signaling pathway. NF-кB inhibitor alleviating MAC-T cell apoptosis is presumably modulated by NF-кB.

  15. Monitoring T-Cell Responses in Translational Studies: Optimization of Dye-Based Proliferation Assay for Evaluation of Antigen-Specific Responses

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    Anja Ten Brinke

    2017-12-01

    Full Text Available Adoptive therapy with regulatory T cells or tolerance-inducing antigen (Ag-presenting cells is innovative and promising therapeutic approach to control undesired and harmful activation of the immune system, as observed in autoimmune diseases, solid organ and bone marrow transplantation. One of the critical issues to elucidate the mechanisms responsible for success or failure of these therapies and define the specificity of the therapy is the evaluation of the Ag-specific T-cell responses. Several efforts have been made to develop suitable and reproducible assays. Here, we focus on dye-based proliferation assays. We highlight with practical examples the fundamental issues to take into consideration for implementation of an effective and sensitive dye-based proliferation assay to monitor Ag-specific responses in patients. The most critical points were used to design a road map to set up and analyze the optimal assay to assess Ag-specific T-cell responses in patients undergoing different treatments. This is the first step to optimize monitoring of tolerance induction, allowing comparison of outcomes of different clinical studies. The road map can also be applied to other therapeutic interventions, not limited to tolerance induction therapies, in which Ag-specific T-cell responses are relevant such as vaccination approaches and cancer immunotherapy.

  16. Vaginal immunization to elicit primary T-cell activation and dissemination.

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    Elena Pettini

    Full Text Available Primary T-cell activation at mucosal sites is of utmost importance for the development of vaccination strategies. T-cell priming after vaginal immunization, with ovalbumin and CpG oligodeoxynucleotide adjuvant as model vaccine formulation, was studied in vivo in hormone-synchronized mice and compared to the one induced by the nasal route. Twenty-four hours after both vaginal or nasal immunization, antigen-loaded dendritic cells were detected within the respective draining lymph nodes. Vaginal immunization elicited a strong recruitment of antigen-specific CD4(+ T cells into draining lymph nodes that was more rapid than the one observed following nasal immunization. T-cell clonal expansion was first detected in iliac lymph nodes, draining the genital tract, and proliferated T cells disseminated towards distal lymph nodes and spleen similarly to what observed following nasal immunization. T cells were indeed activated by the antigen encounter and acquired homing molecules essential to disseminate towards distal lymphoid organs as confirmed by the modulation of CD45RB, CD69, CD44 and CD62L marker expression. A multi-type Galton Watson branching process, previously used for in vitro analysis of T-cell proliferation, was applied to model in vivo CFSE proliferation data in draining lymph nodes 57 hours following immunization, in order to calculate the probabilistic decision of a cell to enter in division, rest in quiescence or migrate/die. The modelling analysis indicated that the probability of a cell to proliferate was higher following vaginal than nasal immunization. All together these data show that vaginal immunization, despite the absence of an organized mucosal associated inductive site in the genital tract, is very efficient in priming antigen-specific CD4(+ T cells and inducing their dissemination from draining lymph nodes towards distal lymphoid organs.

  17. Impaired Autophagy and Defective T Cell Homeostasis in Mice with T Cell-Specific Deletion of Receptor for Activated C Kinase 1

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    Guihua Qiu

    2017-05-01

    Full Text Available Autophagy plays a central role in maintaining T cell homeostasis. Our previous study has shown that hepatocyte-specific deficiency of receptor for activated C kinase 1 (RACK1 leads to lipid accumulation in the liver, accompanied by impaired autophagy, but its in vivo role in T cells remains unclear. Here, we report that mice with T cell-specific deletion of RACK1 exhibit normal intrathymic development of conventional T cells and regulatory T (Treg cells but reduced numbers of peripheral CD4+ and CD8+ T cells. Such defects are cell intrinsic with impaired mitochondrial clearance, increased sensitivity to cell death, and decreased proliferation that could be explained by impaired autophagy. Furthermore, RACK1 is essential for invariant natural T cell development. In vivo, T cell-specific loss of RACK1 dampens concanavalin A-induced acute liver injury. Our data suggest that RACK1 is a key regulator of T cell homeostasis.

  18. Changes in T1 relaxation processes in the bone marrow following treatment in children with acute lymphoblastic leukemia

    International Nuclear Information System (INIS)

    Jensen, K.E.; Thomsen, C.; Henriksen, O.; Hertz, H.; Johansen, H.K.; Yssing, M.

    1990-01-01

    Magnetic resonance imaging (MRI) and T 1 relaxation time measurements of the vertebral bone marrow were performed in 11 children with acute lymphoblastic leukemia (ALL) at diagnosis. Nine of the children were re-examined after chemotherapeutic treatment. The results were compared with histological data from bone marrow biopsies obtained in close association to the MR examinations. Ten age matched children were examined as a control group. A 1.5 Tesla whole body scanner was used for the measurements. The pretreatment T 1 relaxation times of the bone marrow were significantly prolonged, compared to the age matched controls. After chemotherapy the T 1 relaxation times of the children with ALL decreased significantly towards or into the normal range. A significant correlation was found between the T 1 relaxation time and the content of malignant blast cells in the bone marrow. (orig.)

  19. Long-term regulation of Na,K-ATPase pump during T-cell proliferation.

    Science.gov (United States)

    Karitskaya, Inna; Aksenov, Nikolay; Vassilieva, Irina; Zenin, Valerii; Marakhova, Irina

    2010-09-01

    The aim of the study was to elucidate the mechanism responsible for the proliferation-related regulation of Na,K-ATPase pump. Our data demonstrate that in mitogen-stimulated human blood lymphocytes, enhanced ouabain-sensitive Rb(K) fluxes in the middle/late stage of G(0)/G(1)/S transit are associated with the increased number of Na,K-ATPase pumps expressed at the cell surface (as determined by the [(3)H]ouabain binding). Analysis of total RNA (reverse transcription-polymerase chain reaction) and protein (Western blotting) showed a threefold increase in the level of Na,K-ATPase alpha1-subunit and beta1-subunit mRNAs and significant increase in the Na,K-ATPase alpha1-subunit protein during the first day of mitogen-induced proliferation. The elevated K transport as well as the increased expression of Na,K-ATPase is closely associated with the IL-2-dependent stage of T-cell response. The pharmacological inhibition of IL-2-induced MEK/ERK or JAK/STAT cascades suppressed the IL-2-induced proliferation and reduced the functional and protein expressions of Na,K-ATPase. It is concluded that during the lymphocyte transition from resting stage to proliferation, (1) long-term activation of Na,K-ATPase pump is due to the enhanced expression of Na,K-ATPase protein and mRNA, and (2) the cytokine signaling via the IL-2 receptor is necessary for the cell cycle-associated upregulation of Na,K-ATPase.

  20. Chalcones from Chinese liquorice inhibit proliferation of T cells and production of cytokines

    DEFF Research Database (Denmark)

    Barfod, Lea; Kemp, Kåre; Hansen, Majbritt

    2002-01-01

    Licochalcone A (LicA), an oxygenated chalcone, has been shown to inhibit the growth of both parasites and bacteria. In this study, we investigated the effect of LicA and four synthetic analogues on the activity of human peripheral blood mononuclear cell proliferation and cytokine production. Four...... out of five chalcones tested inhibited the proliferation of lymphocytes measured by thymidine incorporation and by flow cytometry. The production of pro- and anti-inflammatory cytokines from monocytes and T cells was also inhibited by four of five chalcones. Furthermore, intracellular detection...... of cytokines revealed that the chalcones inhibited the production rather than the release of the cytokines. Taken together, these results indicate that LicA and some analogues may have immunomodulatory effects, and may thus be candidates not only as anti-microbial agents, but also for the treatment of other...

  1. NKAP regulates iNKT cell proliferation and differentiation into ROR-��t expressing NKT17 cells

    OpenAIRE

    Thapa, Puspa; Chen, Meibo W.; McWilliams, Douglas C.; Belmonte, Paul; Constans, Megan; Sant���Angelo, Derek B.; Shapiro, Virginia Smith

    2016-01-01

    Invariant Natural Killer T (iNKT) cells are a unique lineage with characteristics of both adaptive and innate lymphocytes, and recognize glycolipid presented by an MHC Class I-like CD1d molecule. During thymic development, iNKT cells also differentiate into NKT1, NKT2 and NKT17 functional subsets that preferentially produce cytokines IFN-��, IL-4 and IL-17, respectively, upon activation. Newly selected iNKT cells undergo a burst of proliferation, which is defective in mice with a specific del...

  2. T Cell Subset and Stimulation Strength-Dependent Modulation of T Cell Activation by Kv1.3 Blockers.

    Directory of Open Access Journals (Sweden)

    Wai-Ping Fung-Leung

    Full Text Available Kv1.3 is a voltage-gated potassium channel expressed on T cells that plays an important role in T cell activation. Previous studies have shown that blocking Kv1.3 channels in human T cells during activation results in reduced calcium entry, cytokine production, and proliferation. The aim of the present study was to further explore the effects of Kv1.3 blockers on the response of different human T cell subsets under various stimulation conditions. Our studies show that, unlike the immune suppressor cyclosporine A, the inhibitory effect of Kv1.3 blockers was partial and stimulation strength dependent, with reduced inhibitory efficacy on T cells under strengthened anti-CD3/CD28 stimulations. T cell responses to allergens including house dust mites and ragweed were partially reduced by Kv1.3 blockers. The effect of Kv1.3 inhibition was dependent on T cell subsets, with stronger effects on CCR7- effector memory compared to CCR7+ central memory CD4 T cells. Calcium entry studies also revealed a population of CD4 T cells resistant to Kv1.3 blockade. Activation of CD4 T cells was accompanied with an increase in Kv1.3 currents but Kv1.3 transcripts were found to be reduced, suggesting a posttranscriptional mechanism in the regulation of Kv1.3 activities. In summary, Kv1.3 blockers inhibit T cell activation in a manner that is highly dependent on the T cell identity and stimulation strength, These findings suggest that Kv1.3 blockers inhibit T cells in a unique, conditional manner, further refining our understanding of the therapeutic potential of Kv1.3 blockers.

  3. Nicotinic Acid Adenine Dinucleotide Phosphate Plays a Critical Role in Naive and Effector Murine T Cells but Not Natural Regulatory T Cells*

    Science.gov (United States)

    Ali, Ramadan A.; Camick, Christina; Wiles, Katherine; Walseth, Timothy F.; Slama, James T.; Bhattacharya, Sumit; Giovannucci, David R.; Wall, Katherine A.

    2016-01-01

    Nicotinic acid adenine dinucleotide phosphate (NAADP), the most potent Ca2+ mobilizing second messenger discovered to date, has been implicated in Ca2+ signaling in some lymphomas and T cell clones. In contrast, the role of NAADP in Ca2+ signaling or the identity of the Ca2+ stores targeted by NAADP in conventional naive T cells is less clear. In the current study, we demonstrate the importance of NAADP in the generation of Ca2+ signals in murine naive T cells. Combining live-cell imaging methods and a pharmacological approach using the NAADP antagonist Ned-19, we addressed the involvement of NAADP in the generation of Ca2+ signals evoked by TCR stimulation and the role of this signal in downstream physiological end points such as proliferation, cytokine production, and other responses to stimulation. We demonstrated that acidic compartments in addition to the endoplasmic reticulum were the Ca2+ stores that were sensitive to NAADP in naive T cells. NAADP was shown to evoke functionally relevant Ca2+ signals in both naive CD4 and naive CD8 T cells. Furthermore, we examined the role of this signal in the activation, proliferation, and secretion of effector cytokines by Th1, Th2, Th17, and CD8 effector T cells. Overall, NAADP exhibited a similar profile in mediating Ca2+ release in effector T cells as in their counterpart naive T cells and seemed to be equally important for the function of these different subsets of effector T cells. This profile was not observed for natural T regulatory cells. PMID:26728458

  4. Quantitative proteomic analysis of HIV-1 infected CD4+ T cells reveals an early host response in important biological pathways: Protein synthesis, cell proliferation, and T-cell activation

    Energy Technology Data Exchange (ETDEWEB)

    Navare, Arti T.; Sova, Pavel; Purdy, David E.; Weiss, Jeffrey M. [Department of Microbiology, University of Washington, Seattle, WA (United States); Wolf-Yadlin, Alejandro [Department of Genome Sciences, University of Washington, Seattle, WA (United States); Korth, Marcus J.; Chang, Stewart T.; Proll, Sean C. [Department of Microbiology, University of Washington, Seattle, WA (United States); Jahan, Tahmina A. [Proteomics Resource, UW Medicine at South Lake Union, Seattle, WA (United States); Krasnoselsky, Alexei L.; Palermo, Robert E. [Department of Microbiology, University of Washington, Seattle, WA (United States); Katze, Michael G., E-mail: honey@uw.edu [Department of Microbiology, University of Washington, Seattle, WA (United States); Washington National Primate Research Center, University of Washington, Seattle, WA (United States)

    2012-07-20

    Human immunodeficiency virus (HIV-1) depends upon host-encoded proteins to facilitate its replication while at the same time inhibiting critical components of innate and/or intrinsic immune response pathways. To characterize the host cell response on protein levels in CD4+ lymphoblastoid SUP-T1 cells after infection with HIV-1 strain LAI, we used mass spectrometry (MS)-based global quantitation with iTRAQ (isobaric tag for relative and absolute quantification). We found 266, 60 and 22 proteins differentially expressed (DE) (P-value{<=}0.05) at 4, 8, and 20 hours post-infection (hpi), respectively, compared to time-matched mock-infected samples. The majority of changes in protein abundance occurred at an early stage of infection well before the de novo production of viral proteins. Functional analyses of these DE proteins showed enrichment in several biological pathways including protein synthesis, cell proliferation, and T-cell activation. Importantly, these early changes before the time of robust viral production have not been described before.

  5. Apoptosis-Inducing-Factor-Dependent Mitochondrial Function Is Required for T Cell but Not B Cell Function.

    Science.gov (United States)

    Milasta, Sandra; Dillon, Christopher P; Sturm, Oliver E; Verbist, Katherine C; Brewer, Taylor L; Quarato, Giovanni; Brown, Scott A; Frase, Sharon; Janke, Laura J; Perry, S Scott; Thomas, Paul G; Green, Douglas R

    2016-01-19

    The role of apoptosis inducing factor (AIF) in promoting cell death versus survival remains controversial. We report that the loss of AIF in fibroblasts led to mitochondrial electron transport chain defects and loss of proliferation that could be restored by ectopic expression of the yeast NADH dehydrogenase Ndi1. Aif-deficiency in T cells led to decreased peripheral T cell numbers and defective homeostatic proliferation, but thymic T cell development was unaffected. In contrast, Aif-deficient B cells developed and functioned normally. The difference in the dependency of T cells versus B cells on AIF for function and survival correlated with their metabolic requirements. Ectopic Ndi1 expression rescued homeostatic proliferation of Aif-deficient T cells. Despite its reported roles in cell death, fibroblasts, thymocytes and B cells lacking AIF underwent normal death. These studies suggest that the primary role of AIF relates to complex I function, with differential effects on T and B cells. Copyright © 2016 Elsevier Inc. All rights reserved.

  6. Activated human CD4 T cells express transporters for both cysteine and cystine

    DEFF Research Database (Denmark)

    Levring, Trine Bøegh; Hansen, Ann Kathrine; Nielsen, Bodil Lisbeth

    2012-01-01

    Because naïve T cells are unable to import cystine due to the absence of cystine transporters, it has been suggested that T cell activation is dependent on cysteine generated by antigen presenting cells. The aim of this study was to determine at which phases during T cell activation exogenous...... cystine/cysteine is required and how T cells meet this requirement. We found that early activation of T cells is independent of exogenous cystine/cysteine, whereas T cell proliferation is strictly dependent of uptake of exogenous cystine/cysteine. Naïve T cells express no or very low levels of both...... cystine and cysteine transporters. However, we found that these transporters become strongly up-regulated during T cell activation and provide activated T cells with the required amount of cystine/cysteine needed for T cell proliferation. Thus, T cells are equipped with mechanisms that allow T cell...

  7. c-MPL provides tumor-targeted T-cell receptor-transgenic T cells with costimulation and cytokine signals.

    Science.gov (United States)

    Nishimura, Christopher D; Brenner, Daniel A; Mukherjee, Malini; Hirsch, Rachel A; Ott, Leah; Wu, Meng-Fen; Liu, Hao; Dakhova, Olga; Orange, Jordan S; Brenner, Malcolm K; Lin, Charles Y; Arber, Caroline

    2017-12-21

    Adoptively transferred T-cell receptor (TCR)-engineered T cells depend on host-derived costimulation and cytokine signals for their full and sustained activation. However, in patients with cancer, both signals are frequently impaired. Hence, we developed a novel strategy that combines both essential signals in 1 transgene by expressing the nonlymphoid hematopoietic growth factor receptor c-MPL (myeloproliferative leukemia), the receptor for thrombopoietin (TPO), in T cells. c-MPL signaling activates pathways shared with conventional costimulatory and cytokine receptor signaling. Thus, we hypothesized that host-derived TPO, present in the tumor microenvironment, or pharmacological c-MPL agonists approved by the US Food and Drug Administration could deliver both signals to c-MPL-engineered TCR-transgenic T cells. We found that c-MPL + polyclonal T cells expand and proliferate in response to TPO, and persist longer after adoptive transfer in immunodeficient human TPO-transgenic mice. In TCR-transgenic T cells, c-MPL activation enhances antitumor function, T-cell expansion, and cytokine production and preserves a central memory phenotype. c-MPL signaling also enables sequential tumor cell killing, enhances the formation of effective immune synapses, and improves antileukemic activity in vivo in a leukemia xenograft model. We identify the type 1 interferon pathway as a molecular mechanism by which c-MPL mediates immune stimulation in T cells. In conclusion, we present a novel immunotherapeutic strategy using c-MPL-enhanced transgenic T cells responding to either endogenously produced TPO (a microenvironment factor in hematologic malignancies) or c-MPL-targeted pharmacological agents. © 2017 by The American Society of Hematology.

  8. BAFF induces spleen CD4+ T cell proliferation by down-regulating phosphorylation of FOXO3A and activates cyclin D2 and D3 expression

    International Nuclear Information System (INIS)

    Ji, Fang; Chen, Rongjing; Liu, Baojun; Zhang, Xiaoping; Han, Junli; Wang, Haining; Shen, Gang; Tao, Jiang

    2012-01-01

    Highlights: ► Firstly analyze the mechanism of BAFF and anti-CD3 co-stimulation on purified mouse splenic CD4 + T cells. ► Carrying out siRNA technology to study FOXO3A protein function. ► Helpful to understand the T cell especially CD4 + T cell‘s role in immunological reaction. -- Abstract: The TNF ligand family member “B cell-activating factor belonging to the TNF family” (BAFF, also called BLyS, TALL-1, zTNF-4, and THANK) is an important survival factor for B and T cells. In this study, we show that BAFF is able to induce CD4 + spleen T cell proliferation when co-stimulated with anti-CD3. Expression of phosphorylated FOXO3A was notably down-regulated and cyclins D2 and D3 were up-regulated and higher in the CD4 + T cells when treated with BAFF and anti-CD3, as assessed by Western blotting. Furthermore, after FOXO3A was knocked down, expression of cyclin D1 was unchanged, compared with control group levels, but the expression of cyclins D2 and D3 increased, compared with the control group. In conclusion, our results suggest that BAFF induced CD4 + spleen T cell proliferation by down-regulating the phosphorylation of FOXO3A and then activating cyclin D2 and D3 expression, leading to CD4 + T cell proliferation.

  9. Curtailed T-cell activation curbs effector differentiation and generates CD8+ T cells with a naturally-occurring memory stem cell phenotype.

    Science.gov (United States)

    Zanon, Veronica; Pilipow, Karolina; Scamardella, Eloise; De Paoli, Federica; De Simone, Gabriele; Price, David A; Martinez Usatorre, Amaia; Romero, Pedro; Mavilio, Domenico; Roberto, Alessandra; Lugli, Enrico

    2017-09-01

    Human T memory stem (T SCM ) cells with superior persistence capacity and effector functions are emerging as important players in the maintenance of long-lived T-cell memory and are thus considered an attractive population to be used in adoptive transfer-based immunotherapy of cancer. However, the molecular signals regulating their generation remain poorly defined. Here we show that curtailed T-cell receptor stimulation curbs human effector CD8 + T-cell differentiation and allows the generation of CD45RO - CD45RA + CCR7 + CD27 + CD95 + -phenotype cells from highly purified naïve T-cell precursors, resembling naturally-occurring human T SCM . These cells proliferate extensively in vitro and in vivo, express low amounts of effector-associated genes and transcription factors and undergo considerable self-renewal in response to IL-15 while retaining effector differentiation potential. Such a phenotype is associated with a lower number of mitochondria compared to highly-activated effector T cells committed to terminal differentiation. These results shed light on the molecular signals that are required to generate long-lived memory T cells with potential application in adoptive cell transfer immunotherapy. © 2017 The Authors. European Journal of Immunology published by WILEY-VCH Verlag GmbH & Co.KGaA, Weinheim.

  10. Cell-contact-dependent activation of CD4+ T cells by adhesion molecules on synovial fibroblasts.

    Science.gov (United States)

    Mori, Masato; Hashimoto, Motomu; Matsuo, Takashi; Fujii, Takao; Furu, Moritoshi; Ito, Hiromu; Yoshitomi, Hiroyuki; Hirose, Jun; Ito, Yoshinaga; Akizuki, Shuji; Nakashima, Ran; Imura, Yoshitaka; Yukawa, Naoichiro; Yoshifuji, Hajime; Ohmura, Koichiro; Mimori, Tsuneyo

    2017-05-01

    To determine how cell-cell contact with synovial fibroblasts (SF) influence on the proliferation and cytokine production of CD4 +  T cells. Naïve CD4 +  T cells were cultured with SF from rheumatoid arthritis patients, stimulated by anti-CD3/28 antibody, and CD4 +  T cell proliferation and IFN-γ/IL-17 production were analyzed. To study the role of adhesion molecules, cell contact was blocked by transwell plate or anti-intracellular adhesion molecule-1 (ICAM-1)/vascular cell adhesion molecule-1(VCAM-1) antibody. To study the direct role of adhesion molecules for CD4 +  T cells, CD161 +  or CD161 - naïve CD4 +  T cells were stimulated on plastic plates coated by recombinant ICAM-1 or VCAM-1, and the source of IFN-γ/IL-17 were analyzed. SF enhanced naïve CD4 +  T cell proliferation and IFN-γ/IL-17 production in cell-contact and in part ICAM-1-/VCAM-1-dependent manner. Plate-coated ICAM-1 and VCAM-1 enhanced naïve CD4 +  T cell proliferation and IFN-γ production, while VCAM-1 efficiently promoting IL-17 production. CD161 +  naïve T cells upregulating LFA-1 and VLA-4 were the major source of IFN-γ/IL-17 upon interaction with ICAM-1/VCAM-1. CD4 +  T cells rapidly expand and secrete IFN-γ/IL-17 upon cell-contact with SF via adhesion molecules. Interfering with ICAM-1-/VCAM-1 may be beneficial for inhibiting RA synovitis.

  11. The effect of myostatin on proliferation and lipid accumulation in 3T3-L1 preadipocytes.

    Science.gov (United States)

    Zhu, Hui Juan; Pan, Hui; Zhang, Xu Zhe; Li, Nai Shi; Wang, Lin Jie; Yang, Hong Bo; Gong, Feng Ying

    2015-06-01

    Myostatin is a critical negative regulator of skeletal muscle development, and has been reported to be involved in the progression of obesity and diabetes. In the present study, we explored the effects of myostatin on the proliferation and differentiation of 3T3-L1 preadipocytes by using 3-[4,5-dimethylthiazol-2-yl] 2,5-diphenyl tetrazolium bromide spectrophotometry, intracellular triglyceride (TG) assays, and real-time quantitative RT-PCR methods. The results indicated that recombinant myostatin significantly promoted the proliferation of 3T3-L1 preadipocytes and the expression of proliferation-related genes, including Cyclin B2, Cyclin D1, Cyclin E1, Pcna, and c-Myc, and IGF1 levels in the medium of 3T3-L1 were notably upregulated by 35.2, 30.5, 20.5, 33.4, 51.2, and 179% respectively (all Pmyostatin-treated 3T3-L1 cells. Meanwhile, the intracellular lipid content of myostatin-treated cells was notably reduced as compared with the non-treated cells. Additionally, the mRNA levels of Pparγ, Cebpα, Gpdh, Dgat, Acs1, Atgl, and Hsl were significantly downregulated by 22-76% in fully differentiated myostatin-treated adipocytes. Finally, myostatin regulated the mRNA levels and secretion of adipokines, including Adiponectin, Resistin, Visfatin, and plasminogen activator inhibitor-1 (PAI-1) in 3T3-L1 adipocytes (all Pmyostatin promoted 3T3-L1 proliferation by increasing the expression of cell-proliferation-related genes and by stimulating IGF1 secretion. Myostatin inhibited 3T3-L1 adipocyte differentiation by suppressing Pparγ and Cebpα expression, which consequently deceased lipid accumulation in 3T3-L1 cells by inhibiting the expression of critical lipogenic enzymes and by promoting the expression of lipolytic enzymes. Finally, myostatin modulated the expression and secretion of adipokines in fully differentiated 3T3-L1 adipocytes. © 2015 Society for Endocrinology.

  12. Human memory CD8 T cell effector potential is epigenetically preserved during in vivo homeostasis.

    Science.gov (United States)

    Abdelsamed, Hossam A; Moustaki, Ardiana; Fan, Yiping; Dogra, Pranay; Ghoneim, Hazem E; Zebley, Caitlin C; Triplett, Brandon M; Sekaly, Rafick-Pierre; Youngblood, Ben

    2017-06-05

    Antigen-independent homeostasis of memory CD8 T cells is vital for sustaining long-lived T cell-mediated immunity. In this study, we report that maintenance of human memory CD8 T cell effector potential during in vitro and in vivo homeostatic proliferation is coupled to preservation of acquired DNA methylation programs. Whole-genome bisulfite sequencing of primary human naive, short-lived effector memory (T EM ), and longer-lived central memory (T CM ) and stem cell memory (T SCM ) CD8 T cells identified effector molecules with demethylated promoters and poised for expression. Effector-loci demethylation was heritably preserved during IL-7- and IL-15-mediated in vitro cell proliferation. Conversely, cytokine-driven proliferation of T CM and T SCM memory cells resulted in phenotypic conversion into T EM cells and was coupled to increased methylation of the CCR7 and Tcf7 loci. Furthermore, haploidentical donor memory CD8 T cells undergoing in vivo proliferation in lymphodepleted recipients also maintained their effector-associated demethylated status but acquired T EM -associated programs. These data demonstrate that effector-associated epigenetic programs are preserved during cytokine-driven subset interconversion of human memory CD8 T cells. © 2017 Abdelsamed et al.

  13. Cytokines affecting CD4+T regulatory cells in transplant tolerance. II. Interferon gamma (IFN-γ) promotes survival of alloantigen-specific CD4+T regulatory cells.

    Science.gov (United States)

    Nomura, Masaru; Hodgkinson, Suzanne J; Tran, Giang T; Verma, Nirupama D; Robinson, Catherine; Plain, Karren M; Boyd, Rochelle; Hall, Bruce M

    2017-06-01

    CD4 + T cells that transfer alloantigen-specific transplant tolerance are short lived in culture unless stimulated with specific-donor alloantigen and lymphocyte derived cytokines. Here, we examined if IFN-γ maintained survival of tolerance transferring CD4 + T cells. Alloantigen-specific transplant tolerance was induced in DA rats with heterotopic adult PVG heart allografts by a short course of immunosuppression and these grafts functioned for >100days with no further immunosuppression. In previous studies, we found the CD4 + T cells from tolerant rats that transfer tolerance to an irradiated DA host grafted with a PVG heart, lose their tolerance transferring ability after 3days of culture, either with or without donor alloantigen, and effect rejection of specific-donor grafts. If cultures with specific-donor alloantigen are supplemented by supernatant from ConA activated lymphocytes the tolerance transferring cells survive, suggesting these cells depend on cytokines for their survival. In this study, we found addition of rIFN-γ to MLC with specific-donor alloantigen maintained the capacity of tolerant CD4 + T cells to transfer alloantigen-specific tolerance and their ability to suppress PVG allograft rejection mediated by co-administered naïve CD4 + T cells. IFN-γ suppressed the in vitro proliferation of tolerant CD4 + T cells. Tolerant CD4 + CD25 + T cells did not proliferate in MLC to PVG stimulator cells with no cytokine added, but did when IFN-γ was present. IFN-γ did not alter proliferation of tolerant CD4 + CD25 + T cells to third-party Lewis. Tolerant CD4 + CD25 + T cells' expression of IFN-γ receptor (IFNGR) was maintained in culture when IFN-γ was present. This study suggested that IFN-γ maintained tolerance mediating alloantigen-specific CD4 + CD25 + T cells. Crown Copyright © 2017. Published by Elsevier B.V. All rights reserved.

  14. Apoptosis and T cell depletion during feline infectious peritonitis

    OpenAIRE

    Horzinek, M.C.; Haagmans, B.L.; Egberink, H.F.

    1996-01-01

    Cats that have succumbed to feline infectious peritonitis, an immune- mediated disease caused by variants of feline coronaviruses, show apoptosis and T-cell depletion in their lymphoid organs. The ascitic fluid that develops in the course of the condition causes apoptosis in vitro but only in activated T cells. Since feline infectious peritonitis virus does not infect T cells, and viral proteins did not inhibit T-cell proliferation, we postulate that soluble mediators released during the infe...

  15. Homeostatic T Cell Expansion to Induce Anti-Tumor Autoimmunity in Breast Cancer

    National Research Council Canada - National Science Library

    Baccala, Roberto

    2007-01-01

    ... that (a) homeostatic T-cell proliferation consistently elicits anti-tumor responses; (b) irradiation is more effective than Tcell depletion by antibodies in inducing anti-tumor responses mediated by homeostatic T-cell proliferation...

  16. NOD1 cooperates with TLR2 to enhance T cell receptor-mediated activation in CD8 T cells.

    Directory of Open Access Journals (Sweden)

    Blandine C Mercier

    Full Text Available Pattern recognition receptors (PRR, like Toll-like receptors (TLR and NOD-like receptors (NLR, are involved in the detection of microbial infections and tissue damage by cells of the innate immune system. Recently, we and others have demonstrated that TLR2 can additionally function as a costimulatory receptor on CD8 T cells. Here, we establish that the intracytosolic receptor NOD1 is expressed and functional in CD8 T cells. We show that C12-iEDAP, a synthetic ligand for NOD1, has a direct impact on both murine and human CD8 T cells, increasing proliferation and effector functions of cells activated via their T cell receptor (TCR. This effect is dependent on the adaptor molecule RIP2 and is associated with an increased activation of the NF-κB, JNK and p38 signaling pathways. Furthermore, we demonstrate that NOD1 stimulation can cooperate with TLR2 engagement on CD8 T cells to enhance TCR-mediated activation. Altogether our results indicate that NOD1 might function as an alternative costimulatory receptor in CD8 T cells. Our study provides new insights into the function of NLR in T cells and extends to NOD1 the recent concept that PRR stimulation can directly control T cell functions.

  17. Effect of cell density and HLA-DR incompatibility on T-cell proliferation and forkhead box P3 expression in human mixed lymphocyte reaction.

    Science.gov (United States)

    Song, E Y; Han, S; Yang, B; Morris, G P; Bui, J D

    2015-04-01

    The proliferation rates of human T cells in vitro are affected by some factors such as initial T-cell number, dose of stimulating cells, and duration of culture. The transcription factor forkhead box P3 (FoxP3) has been used to identify regulatory T cells in humans and is thought to correlate with tolerance to allogeneic organ transplant. Thus, it is important to optimize conditions to expand FoxP3 cell proliferation to improve engraftment of allogeneic organ transplants. We studied proliferative responses and FoxP3 expression in divided T cells with the use of flow cytometric analysis of Ki-67 in culture of different concentrations of responding cells (6 × 10(6), 4 × 10(6), 2 × 10(6), 1 × 10(6), and 0.5 × 10(6)cells/mL), different types of stimulating cells (lymphocytes and low density cells), and different numbers of HLA mismatches. The proportion of CD3(+) cells, CD4(+)CD25(+) cells, and CD4(+)CD25(+)FoxP3(+) cells among mononuclear cells were highest at initial cell concentration of 2 × 10(6) responder cells/mL with lymphocytes as stimulators at day-5 mixed lymphocyte reaction (MLR). They were highest at a concentration of 4 × 10(6) responder cells/mL with low density cells as stimulators. The recovery (%), proportion of CD3(+) cells, CD4(+)CD25(+) cells, and CD4(+)CD25(+)FoxP3(+) cells with 2 HLA-DR incompatibility were significantly higher than those of 1 HLA-DR incompatibility at day-5 MLR. Initial cell concentration and HLA-DR incompatibility can affect the generation of FoxP3+ T cells in human MLR. These factors could be considered for efficient generation of Tregs for clinical trials in the future. Copyright © 2015 Elsevier Inc. All rights reserved.

  18. HIV-1 transgenic rats develop T cell abnormalities

    International Nuclear Information System (INIS)

    Reid, William; Abdelwahab, Sayed; Sadowska, Mariola; Huso, David; Neal, Ashley; Ahearn, Aaron; Bryant, Joseph; Gallo, Robert C.; Lewis, George K.; Reitz, Marvin

    2004-01-01

    HIV-1 infection leads to impaired antigen-specific T cell proliferation, increased susceptibility of T cells to apoptosis, progressive impairment of T-helper 1 (Th1) responses, and altered maturation of HIV-1-specific memory cells. We have identified similar impairments in HIV-1 transgenic (Tg) rats. Tg rats developed an absolute reduction in CD4 + and CD8 + T cells able to produce IFN-γ following activation and an increased susceptibility of T cells to activation-induced apoptosis. CD4 + and CD8 + effector/memory (CD45RC - CD62L - ) pools were significantly smaller in Tg rats compared to non-Tg controls, although the converse was true for the naieve (CD45RC + CD62L + ) T cell pool. Our interpretation is that the HIV transgene causes defects in the development of T cell effector function and generation of specific effector/memory T cell subsets, and that activation-induced apoptosis may be an essential factor in this process

  19. Cellular prion protein and γ-synuclein overexpression in LS 174T colorectal cancer cell drives endothelial proliferation-to-differentiation switch

    Directory of Open Access Journals (Sweden)

    Sing-Hui Ong

    2018-03-01

    Full Text Available Background Tumor-induced angiogenesis is an imperative event in pledging new vasculature for tumor metastasis. Since overexpression of neuronal proteins gamma-synuclein (γ-Syn and cellular prion protein (PrPC is always detected in advanced stages of cancer diseases which involve metastasis, this study aimed to investigate whether γ-Syn or PrPC overexpression in colorectal adenocarcinoma, LS 174T cells affects angiogenesis of endothelial cells, EA.hy 926 (EA. Methods EA cells were treated with conditioned media (CM of LS 174T-γ-Syn or LS 174T-PrP, and their proliferation, invasion, migration, adhesion and ability to form angiogenic tubes were assessed using a range of biological assays. To investigate plausible background mechanisms in conferring the properties of EA cells above, nitrite oxide (NO levels were measured and the expression of angiogenesis-related factors was assessed using a human angiogenesis antibody array. Results EA proliferation was significantly inhibited by LS 174T-PrP CM whereas its telomerase activity was reduced by CM of LS 174T-γ-Syn or LS 174T-PrP, as compared to EA incubated with LS 174T CM. Besides, LS 174T-γ-Syn CM or LS 174T-PrP CM inhibited EA invasion and migration in Boyden chamber assay. Furthermore, LS 174T-γ-Syn CM significantly inhibited EA migration in scratch wound assay. Gelatin zymography revealed reduced secretion of MMP-2 and MMP-9 by EA treated with LS 174T-γ-Syn CM or LS 174T-PrP CM. In addition, cell adhesion assay showed lesser LS 174T-γ-Syn or LS 174T-PrP cells adhered onto EA, as compared to LS 174T. In tube formation assay, LS 174T-γ-Syn CM or LS 174T-PrP CM induced EA tube formation. Increased NO secretion by EA treated with LS 174T-γ-Syn CM or LS 174T-PrP CM was also detected. Lastly, decreased expression of pro-angiogenic factors like CXCL16, IGFBP-2 and amphiregulin in LS 174T-γ-Syn CM or LS 174T-PrP CM was detected using the angiogenesis antibody array. Discussion These results

  20. A novel anti-EMMPRIN function-blocking antibody reduces T cell proliferation and neurotoxicity: relevance to multiple sclerosis.

    Science.gov (United States)

    Agrawal, Smriti M; Silva, Claudia; Wang, Janet; Tong, Jade Pui-Wai; Yong, V Wee

    2012-04-05

    Extracellular matrix metalloproteinase inducer (EMMPRIN; CD147, basigin) is an inducer of the expression of several matrix metalloproteinases (MMPs). We reported previously that blocking EMMPRIN activity reduced neuroinflammation and severity of disease in an animal model of multiple sclerosis (MS), experimental autoimmune encephalomyelitis (EAE). To improve upon EMMPRIN blockade, and to help unravel the biological functions of EMMPRIN in inflammatory disorders, we have developed several anti-EMMPRIN monoclonal antibodies. Of these monoclonal antibodies, a particular one, clone 10, was efficient in binding mouse and human cells using several methods of detection. The specificity of clone 10 was demonstrated by its lack of staining of EMMPRIN-null embryos compared to heterozygous and wild-type mouse samples. Functionally, human T cells activated with anti-CD3 and anti-CD28 elevated their expression of EMMPRIN and the treatment of these T cells with clone 10 resulted in decreased proliferation and matrix metalloproteinase- 9 (MMP-9) production. Activated human T cells were toxic to human neurons in culture and clone 10 pretreatment reduced T cell cytotoxicity correspondent with decrease of granzyme B levels within T cells. In vivo, EAE mice treated with clone 10 had a markedly reduced disease score compared to mice treated with IgM isotype control. We have produced a novel anti-EMMPRIN monoclonal antibody that blocks several aspects of T cell activity, thus highlighting the multiple roles of EMMPRIN in T cell biology. Moreover, clone 10 reduces EAE scores in mice compared to controls, and has activity on human cells, potentially allowing for the testing of anti-EMMPRIN treatment not only in EAE, but conceivably also in MS.

  1. A novel anti-EMMPRIN function-blocking antibody reduces T cell proliferation and neurotoxicity: relevance to multiple sclerosis

    Directory of Open Access Journals (Sweden)

    Agrawal Smriti M

    2012-04-01

    Full Text Available Abstract Background Extracellular matrix metalloproteinase inducer (EMMPRIN; CD147, basigin is an inducer of the expression of several matrix metalloproteinases (MMPs. We reported previously that blocking EMMPRIN activity reduced neuroinflammation and severity of disease in an animal model of multiple sclerosis (MS, experimental autoimmune encephalomyelitis (EAE. Methods To improve upon EMMPRIN blockade, and to help unravel the biological functions of EMMPRIN in inflammatory disorders, we have developed several anti-EMMPRIN monoclonal antibodies. Results Of these monoclonal antibodies, a particular one, clone 10, was efficient in binding mouse and human cells using several methods of detection. The specificity of clone 10 was demonstrated by its lack of staining of EMMPRIN-null embryos compared to heterozygous and wild-type mouse samples. Functionally, human T cells activated with anti-CD3 and anti-CD28 elevated their expression of EMMPRIN and the treatment of these T cells with clone 10 resulted in decreased proliferation and matrix metalloproteinase- 9 (MMP-9 production. Activated human T cells were toxic to human neurons in culture and clone 10 pretreatment reduced T cell cytotoxicity correspondent with decrease of granzyme B levels within T cells. In vivo, EAE mice treated with clone 10 had a markedly reduced disease score compared to mice treated with IgM isotype control. Conclusions We have produced a novel anti-EMMPRIN monoclonal antibody that blocks several aspects of T cell activity, thus highlighting the multiple roles of EMMPRIN in T cell biology. Moreover, clone 10 reduces EAE scores in mice compared to controls, and has activity on human cells, potentially allowing for the testing of anti-EMMPRIN treatment not only in EAE, but conceivably also in MS.

  2. Nicotinic Acid Adenine Dinucleotide Phosphate Plays a Critical Role in Naive and Effector Murine T Cells but Not Natural Regulatory T Cells.

    Science.gov (United States)

    Ali, Ramadan A; Camick, Christina; Wiles, Katherine; Walseth, Timothy F; Slama, James T; Bhattacharya, Sumit; Giovannucci, David R; Wall, Katherine A

    2016-02-26

    Nicotinic acid adenine dinucleotide phosphate (NAADP), the most potent Ca(2+) mobilizing second messenger discovered to date, has been implicated in Ca(2+) signaling in some lymphomas and T cell clones. In contrast, the role of NAADP in Ca(2+) signaling or the identity of the Ca(2+) stores targeted by NAADP in conventional naive T cells is less clear. In the current study, we demonstrate the importance of NAADP in the generation of Ca(2+) signals in murine naive T cells. Combining live-cell imaging methods and a pharmacological approach using the NAADP antagonist Ned-19, we addressed the involvement of NAADP in the generation of Ca(2+) signals evoked by TCR stimulation and the role of this signal in downstream physiological end points such as proliferation, cytokine production, and other responses to stimulation. We demonstrated that acidic compartments in addition to the endoplasmic reticulum were the Ca(2+) stores that were sensitive to NAADP in naive T cells. NAADP was shown to evoke functionally relevant Ca(2+) signals in both naive CD4 and naive CD8 T cells. Furthermore, we examined the role of this signal in the activation, proliferation, and secretion of effector cytokines by Th1, Th2, Th17, and CD8 effector T cells. Overall, NAADP exhibited a similar profile in mediating Ca(2+) release in effector T cells as in their counterpart naive T cells and seemed to be equally important for the function of these different subsets of effector T cells. This profile was not observed for natural T regulatory cells. © 2016 by The American Society for Biochemistry and Molecular Biology, Inc.

  3. Active form Notch4 promotes the proliferation and differentiation of 3T3-L1 preadipocytes

    Energy Technology Data Exchange (ETDEWEB)

    Lai, Peng-Yeh [Institute of Molecular Biology and Department of Life Science, National Chung Cheng University, Chiayi 621, Taiwan, ROC (China); Tsai, Chong-Bin [Institute of Molecular Biology and Department of Life Science, National Chung Cheng University, Chiayi 621, Taiwan, ROC (China); Department of Ophthalmology, Chiayi Christian Hospital, Chiayi 600, Taiwan, ROC (China); Tseng, Min-Jen, E-mail: biomjt@ccu.edu.tw [Institute of Molecular Biology and Department of Life Science, National Chung Cheng University, Chiayi 621, Taiwan, ROC (China)

    2013-01-18

    Highlights: ► Notch4IC modulates the ERK pathway and cell cycle to promote 3T3-L1 proliferation. ► Notch4IC facilitates 3T3-L1 differentiation by up-regulating proadipogenic genes. ► Notch4IC promotes proliferation during the early stage of 3T3-L1 adipogenesis. ► Notch4IC enhances differentiation during subsequent stages of 3T3-L1 adipogenesis. -- Abstract: Adipose tissue is composed of adipocytes, which differentiate from precursor cells in a process called adipogenesis. Many signal molecules are involved in the transcriptional control of adipogenesis, including the Notch pathway. Previous adipogenic studies of Notch have focused on Notch1 and HES1; however, the role of other Notch receptors in adipogenesis remains unclear. Q-RT-PCR analyses showed that the augmentation of Notch4 expression during the differentiation of 3T3-L1 preadipocytes was comparable to that of Notch1. To elucidate the role of Notch4 in adipogenesis, the human active form Notch4 (N4IC) was transiently transfected into 3T3-L1 cells. The expression of HES1, Hey1, C/EBPδ and PPARγ was up-regulated, and the expression of Pref-1, an adipogenic inhibitor, was down-regulated. To further characterize the effect of N4IC in adipogenesis, stable cells expressing human N4IC were established. The expression of N4IC promoted proliferation and enhanced differentiation of 3T3-L1 cells compared with those of control cells. These data suggest that N4IC promoted proliferation through modulating the ERK pathway and the cell cycle during the early stage of 3T3-L1 adipogenesis and facilitated differentiation through up-regulating adipogenic genes such as C/EBPα, PPARγ, aP2, LPL and HSL during the middle and late stages of 3T3-L1 adipogenesis.

  4. The subclonal complexity of STIL-TAL1+ T-cell acute lymphoblastic leukaemia.

    Science.gov (United States)

    Furness, Caroline L; Mansur, Marcela B; Weston, Victoria J; Ermini, Luca; van Delft, Frederik W; Jenkinson, Sarah; Gale, Rosemary; Harrison, Christine J; Pombo-de-Oliveira, Maria S; Sanchez-Martin, Marta; Ferrando, Adolfo A; Kearns, Pamela; Titley, Ian; Ford, Anthony M; Potter, Nicola E; Greaves, Mel

    2018-03-20

    Single-cell genetics were used to interrogate clonal complexity and the sequence of mutational events in STIL-TAL1+ T-ALL. Single-cell multicolour FISH was used to demonstrate that the earliest detectable leukaemia subclone contained the STIL-TAL1 fusion and copy number loss of 9p21.3 (CDKN2A/CDKN2B locus), with other copy number alterations including loss of PTEN occurring as secondary subclonal events. In three cases, multiplex qPCR and phylogenetic analysis were used to produce branching evolutionary trees recapitulating the snapshot history of T-ALL evolution in this leukaemia subtype, which confirmed that mutations in key T-ALL drivers, including NOTCH1 and PTEN, were subclonal and reiterative in distinct subclones. Xenografting confirmed that self-renewing or propagating cells were genetically diverse. These data suggest that the STIL-TAL1 fusion is a likely founder or truncal event. Therapies targeting the TAL1 auto-regulatory complex are worthy of further investigation in T-ALL.

  5. T cell receptor-engineered T cells to treat solid tumors: T cell processing toward optimal T cell fitness

    NARCIS (Netherlands)

    C.H.J. Lamers (Cor); S. van Steenbergen-Langeveld (Sabine); M. van Brakel (Mandy); C.M. Groot-van Ruijven (Corrien); P.M.M.L. van Elzakker (Pascal); B.A. van Krimpen (Brigitte); S. Sleijfer (Stefan); J.E.M.A. Debets (Reno)

    2014-01-01

    textabstractTherapy with autologous T cells that have been gene-engineered to express chimeric antigen receptors (CAR) or T cell receptors (TCR) provides a feasible and broadly applicable treatment for cancer patients. In a clinical study in advanced renal cell carcinoma (RCC) patients with CAR T

  6. CARs and other T cell therapies for MM: The clinical experience.

    Science.gov (United States)

    Danhof, Sophia; Hudecek, Michael; Smith, Eric L

    2018-06-01

    Harnessing the endogenous immune system to eliminate malignant cells has long been an intriguing approach. After considerable success in the treatment of B-cell acute lymphoblastic leukemia, chimeric antigen receptor (CAR)-modified T cells have entered early clinical evaluation in the field of multiple myeloma (MM). The choice of suitable non-CD19 target antigens is challenging and a variety of myeloma-associated surface molecules have been under preclinical investigation. Most recent clinical protocols have focused on targeting B-cell maturation antigen (BCMA), and early results are promising. The trials differ in receptor constructs, patient selection, dosing strategies and conditioning chemotherapy and will thus pave the way to eventually define the optimal parameters. Other sources for autologous T-cell therapy of MM include affinity-enhanced T-cell receptor-modified cells and marrow infiltrating lymphocytes. In summary, adoptive T-cell transfer for the treatment of MM is still in its infancy, but if early response rates indicate durability, will be a paradigm changing therapeutic modality for the treatment of MM. Copyright © 2018. Published by Elsevier Ltd.

  7. IL-7 Receptor Mutations and Steroid Resistance in Pediatric T cell Acute Lymphoblastic Leukemia: A Genome Sequencing Study.

    Directory of Open Access Journals (Sweden)

    Yunlei Li

    2016-12-01

    Full Text Available Pediatric acute lymphoblastic leukemia (ALL is the most common childhood cancer and the leading cause of cancer-related mortality in children. T cell ALL (T-ALL represents about 15% of pediatric ALL cases and is considered a high-risk disease. T-ALL is often associated with resistance to treatment, including steroids, which are currently the cornerstone for treating ALL; moreover, initial steroid response strongly predicts survival and cure. However, the cellular mechanisms underlying steroid resistance in T-ALL patients are poorly understood. In this study, we combined various genomic datasets in order to identify candidate genetic mechanisms underlying steroid resistance in children undergoing T-ALL treatment.We performed whole genome sequencing on paired pre-treatment (diagnostic and post-treatment (remission samples from 13 patients, and targeted exome sequencing of pre-treatment samples from 69 additional T-ALL patients. We then integrated mutation data with copy number data for 151 mutated genes, and this integrated dataset was tested for associations of mutations with clinical outcomes and in vitro drug response. Our analysis revealed that mutations in JAK1 and KRAS, two genes encoding components of the interleukin 7 receptor (IL7R signaling pathway, were associated with steroid resistance and poor outcome. We then sequenced JAK1, KRAS, and other genes in this pathway, including IL7R, JAK3, NF1, NRAS, and AKT, in these 69 T-ALL patients and a further 77 T-ALL patients. We identified mutations in 32% (47/146 of patients, the majority of whom had a specific T-ALL subtype (early thymic progenitor ALL or TLX. Based on the outcomes of these patients and their prednisolone responsiveness measured in vitro, we then confirmed that these mutations were associated with both steroid resistance and poor outcome. To explore how these mutations in IL7R signaling pathway genes cause steroid resistance and subsequent poor outcome, we expressed wild

  8. IL-7 Receptor Mutations and Steroid Resistance in Pediatric T cell Acute Lymphoblastic Leukemia: A Genome Sequencing Study

    Science.gov (United States)

    Stubbs, Andrew P.; Vroegindeweij, Eric M.; Smits, Willem K.; van Marion, Ronald; Dinjens, Winand N. M.; Horstmann, Martin; Kuiper, Roland P.; Zaman, Guido J. R.; van der Spek, Peter J.; Pieters, Rob; Meijerink, Jules P. P.

    2016-01-01

    Background Pediatric acute lymphoblastic leukemia (ALL) is the most common childhood cancer and the leading cause of cancer-related mortality in children. T cell ALL (T-ALL) represents about 15% of pediatric ALL cases and is considered a high-risk disease. T-ALL is often associated with resistance to treatment, including steroids, which are currently the cornerstone for treating ALL; moreover, initial steroid response strongly predicts survival and cure. However, the cellular mechanisms underlying steroid resistance in T-ALL patients are poorly understood. In this study, we combined various genomic datasets in order to identify candidate genetic mechanisms underlying steroid resistance in children undergoing T-ALL treatment. Methods and Findings We performed whole genome sequencing on paired pre-treatment (diagnostic) and post-treatment (remission) samples from 13 patients, and targeted exome sequencing of pre-treatment samples from 69 additional T-ALL patients. We then integrated mutation data with copy number data for 151 mutated genes, and this integrated dataset was tested for associations of mutations with clinical outcomes and in vitro drug response. Our analysis revealed that mutations in JAK1 and KRAS, two genes encoding components of the interleukin 7 receptor (IL7R) signaling pathway, were associated with steroid resistance and poor outcome. We then sequenced JAK1, KRAS, and other genes in this pathway, including IL7R, JAK3, NF1, NRAS, and AKT, in these 69 T-ALL patients and a further 77 T-ALL patients. We identified mutations in 32% (47/146) of patients, the majority of whom had a specific T-ALL subtype (early thymic progenitor ALL or TLX). Based on the outcomes of these patients and their prednisolone responsiveness measured in vitro, we then confirmed that these mutations were associated with both steroid resistance and poor outcome. To explore how these mutations in IL7R signaling pathway genes cause steroid resistance and subsequent poor outcome, we

  9. The role of cytokines in T-cell memory in health and disease.

    Science.gov (United States)

    Raeber, Miro E; Zurbuchen, Yves; Impellizzieri, Daniela; Boyman, Onur

    2018-05-01

    Upon stimulation with their cognate antigen, naive T cells undergo proliferation and differentiation into effector cells, followed by apoptosis or survival as precursors of long-lived memory cells. These phases of a T-cell response and the ensuing maintenance of memory T cells are shaped by cytokines, most notably interleukin-2 (IL-2), IL-7, and IL-15 that share the common γ chain (γ c ) cytokine receptor. Steady-state production of IL-7 and IL-15 is necessary for background proliferation and homeostatic survival of CD4 + and CD8 + memory T cells. During immune responses, augmented levels of IL-2, IL-15, IL-21, IL-12, IL-18, and type-I interferons determine the memory potential of antigen-specific effector CD8 + cells, while increased IL-2 and IL-15 cause bystander proliferation of heterologous CD4 + and CD8 + memory T cells. Limiting availability of γ c cytokines, reduction in regulatory T cells or IL-10, and persistence of inflammation or cognate antigen can result in memory T cells, which fail to become cytokine-dependent long-lived cells. Conversely, increased IL-7 and IL-15 can expand memory T cells, including pathogenic tissue-resident memory T cells, as seen in lymphopenia and certain chronic-inflammatory disorders and malignancies. These abovementioned factors impact immunotherapy and vaccines directed at memory T cells in cancer and chronic infection. © 2018 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

  10. The effect of conditional EFNB1 deletion in the T cell compartment on T cell development and function

    Directory of Open Access Journals (Sweden)

    Jin Wei

    2011-12-01

    Full Text Available Abstract Background Eph kinases are the largest family of cell surface receptor tyrosine kinases. The ligands of Ephs, ephrins (EFNs, are also cell surface molecules. Ephs interact with EFNs transmitting signals in both directions, i.e., from Ephs to EFNs and from EFNs to Ephs. EFNB1 is known to be able to co-stimulate T cells in vitro and to modulate thymocyte development in a model of foetal thymus organ culture. To further understand the role of EFNB1 in T cell immunity, we generated T-cell-specific EFNB1 gene knockout mice to assess T cell development and function in these mice. Results The mice were of normal size and cellularity in the thymus and spleen and had normal T cell subpopulations in these organs. The bone marrow progenitors from KO mice and WT control mice repopulated host spleen T cell pool to similar extents. The activation and proliferation of KO T cells was comparable to that of control mice. Naïve KO CD4 cells showed an ability to differentiate into Th1, Th2, Th17 and Treg cells similar to control CD4 cells. Conclusions Our results suggest that the function of EFNB1 in the T cell compartment could be compensated by other members of the EFN family, and that such redundancy safeguards the pivotal roles of EFNB1 in T cell development and function.

  11. Epigenetic control of CD8+ T cell differentiation.

    Science.gov (United States)

    Henning, Amanda N; Roychoudhuri, Rahul; Restifo, Nicholas P

    2018-05-01

    Upon stimulation, small numbers of naive CD8 + T cells proliferate and differentiate into a variety of memory and effector cell types. CD8 + T cells can persist for years and kill tumour cells and virally infected cells. The functional and phenotypic changes that occur during CD8 + T cell differentiation are well characterized, but the epigenetic states that underlie these changes are incompletely understood. Here, we review the epigenetic processes that direct CD8 + T cell differentiation and function. We focus on epigenetic modification of DNA and associated histones at genes and their regulatory elements. We also describe structural changes in chromatin organization that affect gene expression. Finally, we examine the translational potential of epigenetic interventions to improve CD8 + T cell function in individuals with chronic infections and cancer.

  12. Oncogenic Notch signaling in T-cell and B-cell lymphoproliferative disorders.

    Science.gov (United States)

    Chiang, Mark Y; Radojcic, Vedran; Maillard, Ivan

    2016-07-01

    This article highlights recent discoveries about Notch activation and its oncogenic functions in lymphoid malignancies, and discusses the therapeutic potential of Notch inhibition. NOTCH mutations arise in a broad spectrum of lymphoid malignancies and are increasingly scrutinized as putative therapeutic targets. In T-cell acute lymphoblastic leukemia (T-ALL), NOTCH1 mutations affect the extracellular negative regulatory region and lead to constitutive Notch activation, although mutated receptors remain sensitive to Notch ligands. Other NOTCH1 mutations in T-ALL and NOTCH1/2 mutations in multiple B-cell malignancies truncate the C-terminal proline (P), glutamic acid (E), serine (S), threonine (T)-rich (PEST) domain, leading to decreased Notch degradation after ligand-mediated activation. Thus, targeting Notch ligand-receptor interactions could provide therapeutic benefits. In addition, we discuss recent reports on clinical testing of Notch inhibitors in T-ALL that influenced contemporary thinking on the challenges of targeting Notch in cancer. We review advances in the laboratory to address these challenges in regards to drug targets, the Notch-driven metabolome, and the sophisticated protein-protein interactions at Notch-dependent superenhancers that underlie oncogenic Notch functions. Notch signaling is a recurrent oncogenic pathway in multiple T- and B-cell lymphoproliferative disorders. Understanding the complexity and consequences of Notch activation is critical to define optimal therapeutic strategies targeting the Notch pathway.

  13. The cancer-immunity cycle as rational design for synthetic cancer drugs: Novel DC vaccines and CAR T-cells.

    Science.gov (United States)

    Ramachandran, Mohanraj; Dimberg, Anna; Essand, Magnus

    2017-08-01

    Cell therapy is an advanced form of cancer immunotherapy that has had remarkable clinical progress in the past decade in the search for cure of cancer. Most success has been achieved for chimeric antigen receptor (CAR) T-cells where CAR T-cells targeting CD19 show very high complete response rates for patients with refractory acute B-cell acute lymphoblastic leukemia (ALL) and are close to approval for this indication. CD19 CAR T-cells are also effective against B-cell chronic lymphoblastic leukemia (CLL) and B-cell lymphomas. Although encouraging, CAR T-cells have not yet proven clinically effective for solid tumors. This is mainly due to the lack of specific and homogenously expressed targets to direct the T-cells against and a hostile immunosuppressive tumor microenvironment in solid tumors. Cancer vaccines based on dendritic cells (DC) are also making progress although clinical efficacy is still lacking. The likelihood of success is however increasing now when individual tumors can be sequences and patient-specific neoepitopes identified. Neoepitopes and/or neoantigens can then be included in patient-based DC vaccines. This review discusses recent advancements of DC vaccines and CAR T-cells with emphasis on the cancer-immunity cycle, and current efforts to design novel cell therapies. Copyright © 2017 The Author(s). Published by Elsevier Ltd.. All rights reserved.

  14. FoxP3+ regulatory T cells are distinct from leukemia cells in HTLV-1-associated adult T-cell leukemia.

    Science.gov (United States)

    Toulza, Frederic; Nosaka, Kisato; Takiguchi, Masafumi; Pagliuca, Tony; Mitsuya, Hiroaki; Tanaka, Yuetsu; Taylor, Graham P; Bangham, Charles R M

    2009-11-15

    Human T-lymphotropic virus type 1 (HTLV-1) is the causative agent of adult T-cell leukemia/lymphoma (ATLL). It has been postulated that ATLL cells might act as regulatory T cells (T(regs)) which, in common with ATLL cells, express both CD25 and FoxP3, and so contribute to the severe immune suppression typical of ATLL. We report here that the frequency of CD25(+) cells varied independently of the frequency of FoxP3(+) cells in both a cross-sectional study and in a longitudinal study of 2 patients with chronic ATLL. Furthermore, the capacity of ATLL cells to suppress proliferation of heterologous CD4(+)CD25(-) cells correlated with the frequency of CD4(+) FoxP3(+) cells but was independent of CD25 expression. Finally, the frequency of CD4(+)FoxP3(+) cells was inversely correlated with the lytic activity of HTLV-1-specific CTLs in patients with ATLL. We conclude that ATLL is not a tumor of FoxP3(+) regulatory T cells, and that a population of FoxP3(+) cells distinct from ATLL cells has regulatory functions and may impair the cell-mediated immune response to HTLV-1 in patients with ATLL.

  15. CD4 T cells mediate both positive and negative regulation of the immune response to HIV infection: complex role of T follicular helper cells and Regulatory T cells in pathogenesis

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    Chansavath ePhetsouphanh

    2015-01-01

    Full Text Available HIV-1 infection results in chronic activation of cells in lymphoid tissue, including T cells, B cells and myeloid lineage cells. The resulting characteristic hyperplasia is an amalgam of proliferating host immune cells in the adaptive response, increased concentrations of innate response mediators due to viral and bacterial products, and homeostatic responses to inflammation. While it is generally thought that CD4 T cells are greatly depleted, in fact, two types of CD4 T cells appear to be increased, namely regulatory T cells (Tregs and T follicular helper cells (Tfh. These cells have opposing roles, but may both be important in the pathogenic process. Whether Tregs are failing in their role to limit lymphocyte activation is unclear, but there is no doubt now that Tfh are associated with B cell hyperplasia and increased germinal centre activity. Antiretroviral therapy (ART may reduce the lymphocyte activation, but not completely, and therefore there is a need for interventions that selectively enhance normal CD4 function without exacerbating Tfh, B cell or Treg dysfunction.

  16. Andrographolide inhibits growth of human T-cell acute lymphoblastic leukemia Jurkat cells by downregulation of PI3K/AKT and upregulation of p38 MAPK pathways

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    Yang T

    2016-04-01

    Full Text Available Tingfang Yang,1 Shuluan Yao,2 Xianfeng Zhang,3 Yan Guo2 1Department of Pediatrics, Jining No 1 People’s Hospital, Shandong Province, People’s Republic of China; 2Department of Respiratory Medicine, Jining Medical University Affiliated Hospital, Shandong Province, People’s Republic of China; 3Department of Psychiatry, Jining Psychiatric Hospital, Shandong Province, People’s Republic of China Abstract: T-cell acute lymphoblastic leukemia (T-ALL as a prevalent hematologic malignancy is one of the most common malignant tumors worldwide in children. Andrographolide (Andro, the major active component from Andrographis paniculata, has been shown to possess antitumor activities in several types of cancer cells. However, whether Andro would inhibit T-ALL cell growth remains unclear. In this study, we investigated the cytotoxic effect of Andro on human T-ALL Jurkat cells and explored the mechanisms of cell death. Cell apoptosis was assayed by flow cytometry, and the signaling transduction for Andro was analyzed by Western blotting. The results indicated 10 µg/mL Andro could significantly induce Jurkat cells’ apoptosis, depending on the inhibition of PI3K/AKT pathway. Moreover, Andro-induced apoptosis is enhanced by AKT-selective inhibitor LY294002. ERK- or JNK-selective inhibitors PD98059 and SP600125 had no effect on Andro-induced apoptosis. In addition, p38 inhibitor SB203580 could reverse Andro-induced apoptosis in Jurkat cells. We also found that the protein expression of p-p53 and p-p38 were increased after Andro treatments. The result of an in vivo study also demonstrated Andro’s dose-dependent inhibition in subcutaneous Jurkat xenografts. In conclusion, our findings explained a novel mechanism of drug action by Andro in Jurkat cells and suggested that Andro might be developed into a new candidate therapy for T-ALL patients in the coming days. Keywords: andrographolide, PI3K, AKT, Burkitt lymphoma, Jurkat cell

  17. The growth hormone-releasing hormone (GHRH) antagonist JV-1-36 inhibits proliferation and survival of human ectopic endometriotic stromal cells (ESCs) and the T HESC cell line.

    Science.gov (United States)

    Annunziata, Marta; Grande, Cristina; Scarlatti, Francesca; Deltetto, Francesco; Delpiano, Elena; Camanni, Marco; Ghigo, Ezio; Granata, Riccarda

    2010-08-01

    To determine the effect of the GHRH antagonist JV-1-36 on proliferation and survival of primary ectopic human endometriotic stromal cells (ESCs) and the T HESC cell line. Prospective laboratory study. University hospital. 22 women with endometriosis (aged 34.8+/-5.7 years) undergoing therapeutic laparoscopy. Eutopic (n=10) and ectopic (n=22) endometrial tissues were collected from women who underwent therapeutic laparoscopic surgery for endometriosis (stage III/IV). Expression of GHRH, GHRH receptor (GHRH-R) and GHRH-R splice variant (SV) 1 mRNA was determined by reverse-transcription polymerase chain reaction (RT-PCR). The ESC proliferation was assessed by 5-bromo-2-deoxyuridine incorporation, cell survival by 3-[4,5-dimethylthiazol-2-yl]-2,5-diphenyl tetrazolium bromide (MTT) and Trypan blue assay. The T HESC survival was evaluated by MTT, cyclic adenosine monophosphate (cAMP) levels by ELISA, extracellular signal-regulated kinases 1 and 2 (ERK1/2) phosphorylation by Western blot, and insulin-like growth factor (IGF)-2 mRNA by real-time PCR. The ESCs and T HESCs, but not normal endometrial tissues, expressed GHRH-R mRNA; SV1 mRNA was determined in normal endometrial tissues, ESCs, and T HESCs; GHRH mRNAwas found in T HESCs; JV-1-36 inhibited ESC proliferation and ESC and T HESC survival. In T HESCs, JV-1-36 reduced cAMP production and ERK1/2 phosphorylation but had no effect on IGF-2 mRNA expression. The GHRH antagonist JV-1-36 inhibits endometriotic cell proliferation and survival, suggesting that GHRH antagonist may represent promising tools for treatment of endometriosis. Copyright (c) 2010 American Society for Reproductive Medicine. Published by Elsevier Inc. All rights reserved.

  18. Differential responses of human regulatory T cells (Treg and effector T cells to rapamycin.

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    Laura Strauss

    Full Text Available BACKGROUND: The immunosuppressive drug rapamycin (RAPA promotes the expansion of CD4(+ CD25(highFoxp3(+ regulatory T cells via mechanisms that remain unknown. Here, we studied expansion, IL-2R-gamma chain signaling, survival pathways and resistance to apoptosis in human Treg responding to RAPA. METHODOLOGY/PRINCIPAL FINDINGS: CD4(+CD25(+ and CD4(+CD25(neg T cells were isolated from PBMC of normal controls (n = 21 using AutoMACS. These T cell subsets were cultured in the presence of anti-CD3/CD28 antibodies and 1000 IU/mL IL-2 for 3 to 6 weeks. RAPA (1-100 nM was added to half of the cultures. After harvest, the cell phenotype, signaling via the PI3K/mTOR and STAT pathways, expression of survival proteins and Annexin V binding were determined and compared to values obtained with freshly-separated CD4(+CD25(high and CD4(+CD25(neg T cells. Suppressor function was tested in co-cultures with autologous CFSE-labeled CD4(+CD25(neg or CD8(+CD25(neg T-cell responders. The frequency and suppressor activity of Treg were increased after culture of CD4(+CD25(+ T cells in the presence of 1-100 nM RAPA (p<0.001. RAPA-expanded Treg were largely CD4(+CD25(highFoxp3(+ cells and were resistant to apoptosis, while CD4(+CD25(neg T cells were sensitive. Only Treg upregulated anti-apoptotic and down-regulated pro-apoptotic proteins. Treg expressed higher levels of the PTEN protein than CD4(+CD25(neg cells. Activated Treg+/-RAPA preferentially phosphorylated STAT5 and STAT3 and did not utilize the PI3K/mTOR pathway. CONCLUSIONS/SIGNIFICANCE: RAPA favors Treg expansion and survival by differentially regulating signaling, proliferation and sensitivity to apoptosis of human effector T cells and Treg after TCR/IL-2 activation.

  19. Human Epidermal Langerhans Cells Maintain Immune Homeostasis in Skin by Activating Skin Resident Regulatory T Cells

    Science.gov (United States)

    Seneschal, Julien; Clark, Rachael A.; Gehad, Ahmed; Baecher-Allan, Clare M.; Kupper, Thomas S.

    2013-01-01

    Recent discoveries indicate that the skin of a normal individual contains 10-20 billion resident memory T cells ( which include various T helper, T cytotoxic, and T regulatory subsets, that are poised to respond to environmental antigens. Using only autologous human tissues, we report that both in vitro and in vivo, resting epidermal Langerhan cells (LC) selectively and specifically induced the activation and proliferation of skin resident regulatory T cells (Treg), a minor subset of skin resident memory T cells. In the presence of foreign pathogen, however, the same LC activated and induced proliferation of effector memory T (Tem) cells and limited Treg cells activation. These underappreciated properties of LC: namely maintenance of tolerance in normal skin, and activation of protective skin resident memory T cells upon infectious challenge, help clarify the role of LC in skin. PMID:22560445

  20. Murine T cell activation is regulated by surfen (bis-2-methyl-4-amino-quinolyl-6-carbamide)

    Energy Technology Data Exchange (ETDEWEB)

    Warford, Jordan, E-mail: jordan.warford@dal.ca [Department of Pathology, Dalhousie University, Tupper Building, 5850 College Street, Halifax, Nova Scotia B3H 4R2 (Canada); Doucette, Carolyn D., E-mail: carolyn.doucette@dal.ca [Department of Microbiology and Immunology, Dalhousie University, Tupper Building, 5850 College Street, Halifax, Nova Scotia B3H 4R2 (Canada); Hoskin, David W., E-mail: d.w.hoskin@dal.ca [Department of Pathology, Dalhousie University, Tupper Building, 5850 College Street, Halifax, Nova Scotia B3H 4R2 (Canada); Department of Microbiology and Immunology, Dalhousie University, Tupper Building, 5850 College Street, Halifax, Nova Scotia B3H 4R2 (Canada); Easton, Alexander S., E-mail: alexander.easton@dal.ca [Department of Pathology, Dalhousie University, Tupper Building, 5850 College Street, Halifax, Nova Scotia B3H 4R2 (Canada); Department of Microbiology and Immunology, Dalhousie University, Tupper Building, 5850 College Street, Halifax, Nova Scotia B3H 4R2 (Canada); Department of Surgery (Neurosurgery), Dalhousie University, Tupper Building, 5850 College Street, Halifax, Nova Scotia B3H 4R2 (Canada)

    2014-01-10

    Highlights: •Surfen is the first inhibitor of glycosaminoglycan function to be studied in murine T cells. •Surfen reduces T cell proliferation stimulated in vitro and in vivo. •Surfen reduces CD25 expression in T cells activated in vivo but not in vitro. •Surfen increases T cell proliferation when T cell receptor activation is bypassed. •Surfen’s effects are blocked by co-administration of heparin sulfate. -- Abstract: Surfen (bis-2-methyl-4-amino-quinolyl-6-carbamide) binds to glycosaminoglycans (GAGs) and has been shown to influence their function, and the function of proteoglycans (complexes of GAGs linked to a core protein). T cells synthesize, secrete and express GAGs and proteoglycans which are involved in several aspects of T cell function. However, there are as yet no studies on the effect of GAG-binding agents such as surfen on T cell function. In this study, surfen was found to influence murine T cell activation. Doses between 2.5 and 20 μM produced a graduated reduction in the proliferation of T cells activated with anti-CD3/CD28 antibody-coated T cell expander beads. Surfen (20 mg/kg) was also administered to mice treated with anti-CD3 antibody to activate T cells in vivo. Lymphocytes from surfen-treated mice also showed reduced proliferation and lymph node cell counts were reduced. Surfen reduced labeling with a cell viability marker (7-ADD) but to a much lower extent than its effect on proliferation. Surfen also reduced CD25 (the α-subunit of the interleukin (IL)-2 receptor) expression with no effect on CD69 expression in T cells treated in vivo but not in vitro. When receptor activation was bypassed by treating T cells in vitro with phorbyl myristate acetate (10 ng/ml) and ionomycin (100 ng/ml), surfen treatment either increased proliferation (10 μM) or had no effect (2.5, 5 and 20 μM). In vitro treatment of T cells with surfen had no effect on IL-2 or interferon-γ synthesis and did not alter proliferation of the IL-2 dependent cell

  1. Chimeric antigen receptor-modified T cells for acute lymphoid leukemia.

    Science.gov (United States)

    Grupp, Stephan A; Kalos, Michael; Barrett, David; Aplenc, Richard; Porter, David L; Rheingold, Susan R; Teachey, David T; Chew, Anne; Hauck, Bernd; Wright, J Fraser; Milone, Michael C; Levine, Bruce L; June, Carl H

    2013-04-18

    Chimeric antigen receptor-modified T cells with specificity for CD19 have shown promise in the treatment of chronic lymphocytic leukemia (CLL). It remains to be established whether chimeric antigen receptor T cells have clinical activity in acute lymphoblastic leukemia (ALL). Two children with relapsed and refractory pre-B-cell ALL received infusions of T cells transduced with anti-CD19 antibody and a T-cell signaling molecule (CTL019 chimeric antigen receptor T cells), at a dose of 1.4×10(6) to 1.2×10(7) CTL019 cells per kilogram of body weight. In both patients, CTL019 T cells expanded to a level that was more than 1000 times as high as the initial engraftment level, and the cells were identified in bone marrow. In addition, the chimeric antigen receptor T cells were observed in the cerebrospinal fluid (CSF), where they persisted at high levels for at least 6 months. Eight grade 3 or 4 adverse events were noted. The cytokine-release syndrome and B-cell aplasia developed in both patients. In one child, the cytokine-release syndrome was severe; cytokine blockade with etanercept and tocilizumab was effective in reversing the syndrome and did not prevent expansion of chimeric antigen receptor T cells or reduce antileukemic efficacy. Complete remission was observed in both patients and is ongoing in one patient at 11 months after treatment. The other patient had a relapse, with blast cells that no longer expressed CD19, approximately 2 months after treatment. Chimeric antigen receptor-modified T cells are capable of killing even aggressive, treatment-refractory acute leukemia cells in vivo. The emergence of tumor cells that no longer express the target indicates a need to target other molecules in addition to CD19 in some patients with ALL.

  2. Abnormal proliferation of CD4- CD8+ gammadelta+ T cells with chromosome 6 anomaly: role of Fas ligand expression in spontaneous regression of the cells.

    Science.gov (United States)

    Ichikawa, N; Kitano, K; Ito, T; Nakazawa, T; Shimodaira, S; Ishida, F; Kiyosawa, K

    1999-04-01

    We report a case of granular lymphocyte proliferative disorder accompanied with hemolytic anemia and neutropenia. Phenotypes of the cells were T cell receptor gammadelta+ CD3+ CD4- CD8+ CD16+ CD56- CD57-. Southern blot analysis of T cell receptor beta and gamma chains demonstrated rearranged bands in both. Chromosomal analysis after IL-2 stimulation showed deletion of chromosome 6. Sorted gammadelta+ T cells showed an increase in Fas ligand expression compared with the levels in sorted alphabeta+ T cells. The expression of Fas ligand on these gammadelta+ T cells increased after IL-2 stimulation. The patient's anemia improved along with a decrease in granular lymphocyte count and disappearance of the abnormal karyotype without treatment. The expression of Fas ligand may be involved in spontaneous regression of granular lymphocyte proliferation with hemolytic anemia.

  3. Vγ4+ T Cells: A Novel IL-17-Producing γδ T Subsets during the Early Phase of Chlamydial Airway Infection in Mice

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    Li-da Sun

    2018-01-01

    Full Text Available Our previous studies showed that γδ T cells provided immune protection against Chlamydial muridarum (Cm, an obligate intracellular strain of chlamydia trachomatis, lung infection by producing abundant IL-17. In this study, we investigated the proliferation and activation of lung γδ T cell subsets, specifically the IL-17 and IFNγ production by them following Cm lung infection. Our results found that five γδ T cell subsets, Vγ1+ T, Vγ2+ T, Vγ4+ T, Vγ5+ T, and Vγ6+ T, expressed in lungs of naïve mice, while Cm lung infection mainly induced the proliferation and activation of Vγ4+ T cells at day 3 p.i., following Vγ1+ T cells at day 7 p.i. Cytokine detection showed that Cm lung infection induced IFNγ secretion firstly by Vγ4+ T cells at very early stage (day 3 and changed to Vγ1+ T cells at midstage (day 7. Furthermore, Vγ4+ T cell is the main γδ T cell subset that secretes IL-17 at the very early stage of Cm lung infection and Vγ1+ T cell did not secrete IL-17 during the infection. These findings provide in vivo evidence that Vγ4+T cells are the major IL-17 and IFNγ-producing γδ T cell subsets at the early period of Cm lung infection.

  4. Systemic T Cells Immunosuppression of Glioma Stem Cell-Derived Exosomes Is Mediated by Monocytic Myeloid-Derived Suppressor Cells.

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    Rossana Domenis

    Full Text Available A major contributing factor to glioma development and progression is its ability to evade the immune system. Nano-meter sized vesicles, exosomes, secreted by glioma-stem cells (GSC can act as mediators of intercellular communication to promote tumor immune escape. Here, we investigated the immunomodulatory properties of GCS-derived exosomes on different peripheral immune cell populations. Healthy donor peripheral blood mononuclear cells (PBMCs stimulated with anti-CD3, anti-CD28 and IL-2, were treated with GSC-derived exosomes. Phenotypic characterization, cell proliferation, Th1/Th2 cytokine secretion and intracellular cytokine production were analysed by distinguishing among effector T cells, regulatory T cells and monocytes. In unfractionated PBMCs, GSC-derived exosomes inhibited T cell activation (CD25 and CD69 expression, proliferation and Th1 cytokine production, and did not affect cell viability or regulatory T-cell suppression ability. Furthermore, exosomes were able to enhance proliferation of purified CD4+ T cells. In PBMCs culture, glioma-derived exosomes directly promoted IL-10 and arginase-1 production and downregulation of HLA-DR by unstimulated CD14+ monocytic cells, that displayed an immunophenotype resembling that of monocytic myeloid-derived suppressor cells (Mo-MDSCs. Importantly, the removal of CD14+ monocytic cell fraction from PBMCs restored T-cell proliferation. The same results were observed with exosomes purified from plasma of glioblastoma patients. Our results indicate that glioma-derived exosomes suppress T-cell immune response by acting on monocyte maturation rather than on direct interaction with T cells. Selective targeting of Mo-MDSC to treat glioma should be considered with regard to how immune cells allow the acquirement of effector functions and therefore counteracting tumor progression.

  5. Effects of PKM2 Gene Silencing on the Proliferation and Apoptosis of Colorectal Cancer LS-147T and SW620 Cells

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    Ran Ao

    2017-07-01

    Full Text Available Background/Aims: This paper aims to explore the effects of pyruvate kinase (PK M2 gene silencing on the proliferation and apoptosis of colorectal cancer (CRC LS-147T and SW620 cells. Methods: CRC LS-147T and SW620 cells highly expressing PKM2 were randomly selected by quantitative real-time polymerase chain reaction (qRT-PCR and then assigned into the blank (no transfection, PKM2-shRNA (transfection with shRNA and empty plasmid (transfection with empty plasmid groups. Immunofluorescence was applied to detect PKM2 protein expression. qRT-PCR and Western blotting were conducted to assess mRNA and protein expression of PKM2, p53 and p21. The cell counting kit-8 (CCK-8 assay was used to assess cell proliferation. Flow cytometry was used to assess the cell cycle and apoptosis rate, and a senescence-associated β-galactosidase staining kit was used to assess cell senescence. Results: PKM2 exhibited high mRNA expression among CRC LS-147T and SW620 cells with remarkable protein expression noted in the cytoplasm and nucleus. The PKM2-shRNA group exhibited reduced PKM2 mRNA and protein expression, whereas p53 and p21 expression was increased compared with the blank and empty plasmid groups. Cell proliferation in PKM2-shRNA cells decreased significantly compared with the blank group and empty plasmid groups. The PKM2-shRNA group exhibited more cells in the G1 phase and fewer cells in the G2/M phase compared with the blank and empty plasmid groups. In addition, the PKM2-shRNA group exhibited significantly increased apoptosis rates and β-galactosidase activity compared with the blank and empty plasmid groups. Conclusion: Our study demonstrates that PKM2 gene silencing suppresses proliferation and promotes apoptosis in LS-147T and SW620 cells.

  6. Tumor cells and memory T cells converge at glycolysis: Therapeutic implications

    OpenAIRE

    Karthikeyan, Swathi; Geschwind, Jean-Francois; Ganapathy-Kanniappan, Shanmugasundaram

    2014-01-01

    In the immune system, activation of naïve T (Tn) cells into effector T cells (Teff) involves a metabolic switch to glycolysis to promote rapid proliferation and differentiation. In the October issue of The Journal of Clinical Investigation, Sukumar et al. have demonstrated that in CD8+ memory T (Tems) cells glycolytic phenotype contributes to the shortened lifespan of Tems. Conversely, inhibition of glycolysis in Tems not only extended their viability but also augmented desirable properties. ...

  7. mTOR Inhibition Attenuates Dextran Sulfate Sodium-Induced Colitis by Suppressing T Cell Proliferation and Balancing TH1/TH17/Treg Profile.

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    Shurong Hu

    Full Text Available It has been established that mammalian target of Rapamycin (mTOR inhibitors have anti-inflammatory effects in models of experimental colitis. However, the underlying mechanism is largely unknown. In this research, we investigate the anti-inflammatory effects of AZD8055, a potent mTOR inhibitor, on T cell response in dextran sulfate sodium (DSS-induced colitis in mice, a commonly used animal model of inflammatory bowel diseases (IBD. Severity of colitis is evaluated by changing of body weight, bloody stool, fecal consistency, histology evaluation and cytokine expression. We find that AZD8055 treatment attenuates DSS-induced body weight loss, colon length shortening and pathological damage of the colon. And AZD8055 treatment decreases colonic expression of genes encoding the pro-inflammatory cytokines interferon-γ, interleukin (IL-17A, IL-1β,IL-6 and tumor necrosis factor(TNF-a and increases colonic expression of anti-inflammatory cytokines IL-10. We show that AZD8055 treatment decreases the percentages of CD4+ T cells and CD8+ T cells in spleen, lymph nodes and peripheral blood of mice. We also find that AZD8055 treatment significantly reduces the number of T helper 1(TH1 cells and TH17 cells and increases regulatory T (Treg cells in the lamina propria and mesenteric lymph nodes. Furthermore, we demonstrates that AZD8055 suppresses the proliferation of CD4+ and CD8+ T cells and the differentiation of TH1/TH17 cells and expands Treg cells in vitro. The results suggest that, in experimental colitis, AZD8055 exerts anti-inflammatory effect by regulating T helper cell polarization and proliferation.

  8. BAFF induces spleen CD4{sup +} T cell proliferation by down-regulating phosphorylation of FOXO3A and activates cyclin D2 and D3 expression

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    Ji, Fang; Chen, Rongjing [Department of Orthodontics, Ninth People' s Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai Key Laboratory of Stomatology, Shanghai (China); Liu, Baojun [Laboratory of Lung, Inflammation and Cancers, Huashan Hospital, Fudan University, Shanghai (China); Zhang, Xiaoping [Department of Nuclear Medicine, Shanghai 10th People' s Hospital, Tongji University School of Medicine, Shanghai 200072 (China); Han, Junli; Wang, Haining [Department of General Dentistry, Ninth People' s Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai Key Laboratory of Stomatology, Shanghai (China); Shen, Gang [Department of Orthodontics, Ninth People' s Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai Key Laboratory of Stomatology, Shanghai (China); Tao, Jiang, E-mail: taojiang2012@yahoo.cn [Department of General Dentistry, Ninth People' s Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai Key Laboratory of Stomatology, Shanghai (China)

    2012-09-07

    Highlights: Black-Right-Pointing-Pointer Firstly analyze the mechanism of BAFF and anti-CD3 co-stimulation on purified mouse splenic CD4{sup +} T cells. Black-Right-Pointing-Pointer Carrying out siRNA technology to study FOXO3A protein function. Black-Right-Pointing-Pointer Helpful to understand the T cell especially CD4{sup +} T cell's role in immunological reaction. -- Abstract: The TNF ligand family member 'B cell-activating factor belonging to the TNF family' (BAFF, also called BLyS, TALL-1, zTNF-4, and THANK) is an important survival factor for B and T cells. In this study, we show that BAFF is able to induce CD4{sup +} spleen T cell proliferation when co-stimulated with anti-CD3. Expression of phosphorylated FOXO3A was notably down-regulated and cyclins D2 and D3 were up-regulated and higher in the CD4{sup +} T cells when treated with BAFF and anti-CD3, as assessed by Western blotting. Furthermore, after FOXO3A was knocked down, expression of cyclin D1 was unchanged, compared with control group levels, but the expression of cyclins D2 and D3 increased, compared with the control group. In conclusion, our results suggest that BAFF induced CD4{sup +} spleen T cell proliferation by down-regulating the phosphorylation of FOXO3A and then activating cyclin D2 and D3 expression, leading to CD4{sup +} T cell proliferation.

  9. Protein energy malnutrition impairs homeostatic proliferation of memory CD8 T cells.

    Science.gov (United States)

    Iyer, Smita S; Chatraw, Janel Hart; Tan, Wendy G; Wherry, E John; Becker, Todd C; Ahmed, Rafi; Kapasi, Zoher F

    2012-01-01

    Nutrition is a critical but poorly understood determinant of immunity. There is abundant epidemiological evidence linking protein malnutrition to impaired vaccine efficacy and increased susceptibility to infections; yet, the role of dietary protein in immune memory homeostasis remains poorly understood. In this study, we show that protein-energy malnutrition induced in mice by low-protein (LP) feeding has a detrimental impact on CD8 memory. Relative to adequate protein (AP)-fed controls, LP feeding in lymphocytic choriomeningitis virus (LCMV)-immune mice resulted in a 2-fold decrease in LCMV-specific CD8 memory T cells. Adoptive transfer of memory cells, labeled with a division tracking dye, from AP mice into naive LP or AP mice demonstrated that protein-energy malnutrition caused profound defects in homeostatic proliferation. Remarkably, this defect occurred despite the lymphopenic environment in LP hosts. Whereas Ag-specific memory cells in LP and AP hosts were phenotypically similar, memory cells in LP hosts were markedly less responsive to polyinosinic-polycytidylic acid-induced acute proliferative signals. Furthermore, upon recall, memory cells in LP hosts displayed reduced proliferation and protection from challenge with LCMV-clone 13, resulting in impaired viral clearance in the liver. The findings show a metabolic requirement of dietary protein in sustaining functional CD8 memory and suggest that interventions to optimize dietary protein intake may improve vaccine efficacy in malnourished individuals.

  10. Abnormalities in iNKT cells are associated with impaired ability of monocytes to produce IL-10 and suppress T-cell proliferation in sarcoidosis.

    Science.gov (United States)

    Crawshaw, Anjali; Kendrick, Yvonne R; McMichael, Andrew J; Ho, Ling-Pei

    2014-07-01

    Sarcoidosis is a multisystem granulomatous disorder characterized by marked T-cell expansion of T helper 1 (Th1) cells. The cause of T-cell overactivity is unknown. We hypothesized that interleukin-10 (IL-10) production by a yet undefined cell type might be defective, resulting in loss of regulation of T-cell activity. Focusing on IL-10-producing monocytes, we first showed that monocytes isolated from the peripheral blood of corticosteroid-naïve sarcoidosis patients (n = 51) produced less IL-10 compared to controls, and were less able to suppress T-cell proliferation. In addition, monocytic IL-10 production correlated negatively with disease activity score. As invariant natural killer T (iNKT) cells are known to both interact with monocytes and be reduced in sarcoidosis patients, we then asked whether iNKT-specific defects might be responsible for this reduced IL-10 production. We found that greater numbers of circulating iNKT cells was associated with higher IL-10 production. Moreover, iNKT cells enhanced monocytic IL-10 production in vitro. Defective IL-10 production and T-cell suppression by sarcoidosis monocytes could be restored following their coculture with iNKT cells, in a CD1d- and cell contact-dependent process. We suggest that reduced iNKT-cell numbers in sarcoidosis may lead to impaired monocytic IL-10 production and unchecked T-cell expansion in sarcoidosis. These findings provide fresh insight into the mechanism of sarcoidosis disease, and interaction between iNKT cells and monocytes. © 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  11. Antigen presentation by resting B cells. Radiosensitivity of the antigen-presentation function and two distinct pathways of T cell activation

    International Nuclear Information System (INIS)

    Ashwell, J.D.; DeFranco, A.L.; Paul, W.E.; Schwartz, R.H.

    1984-01-01

    In this report we have examined the ability of small resting B cells to act as antigen-presenting cells (APC) to antigen-specific MHC-restricted T cells as assessed by either T cell proliferation or T cell-dependent B cell stimulation. We found that 10 of 14 in vitro antigen-specific MHC-restricted T cell clones and lines and three of four T cell hybridomas could be induced to either proliferate or secrete IL-2 in the presence of lightly irradiated (1,000 rads) purified B cells and the appropriate foreign antigen. All T cell lines and hybridomas were stimulated to proliferate or make IL-2 by macrophage- and dendritic cell-enriched populations and all T cells tested except one hybridoma caused B cell activation when stimulated with B cells as APC. Furthermore, lightly irradiated, highly purified syngeneic B cells were as potent a source of APC for inducing B cell activation as were low density dendritic and macrophage-enriched cells. Lymph node T cells freshly taken from antigen-primed animals were also found to proliferate when cultured with purified B cells and the appropriate antigen. This APC function was easily measured when the cells were irradiated with 1,000 rads, but was greatly diminished or absent when they were irradiated with 3,300 rads. In addition, this radiosensitivity allowed us to easily distinguish B cell antigen presentation from presentation by the dendritic cell and macrophage, as the latter was resistant to 3,300 rads. Finally, one T cell clone that failed to proliferate when B cells were used as APC was able to recruit allogeneic B cells to proliferate in the presence of syngeneic B cells and the appropriate antigen. This result suggests that there are at least two distinct pathways of activation in T cells, one that leads to T cell proliferation and one that leads to the secretion of B cell recruitment factor(s)

  12. Nocardia rubra cell-wall skeleton promotes CD4+ T cell activation and drives Th1 immune response.

    Science.gov (United States)

    Wang, Guangchuan; Wu, Jie; Miao, Miao; Dou, Heng; Nan, Ning; Shi, Mingsheng; Yu, Guang; Shan, Fengping

    2017-08-01

    Several lines of evidences have shown that Nocardia rubra cell wall skeleton (Nr-CWS) has immunoregulatory and anti-tumor activities. However, there is no information about the effect of Nr-CWS on CD4 + T cells. The aim of this study was to explore the effect of Nr-CWS on the phenotype and function of CD4 + T cells. Our results of in vitro experiments showed that Nr-CWS could significantly up-regulate the expression of CD69 and CD25 on CD4 + T cells, promote the proliferation of CD4 + T cells, increase the production of IFN-γ, TNF-α and IL-2 in the supernatants, but has no significant effect on the apoptosis and death of CD4 + T cells. Results of in vivo experiments showed that Nr-CWS could promote the proliferation of CD4 + T cells, and increase the production of IL-2, IFN-γ and TNF-α (Th1 type cytokines). These data suggest that Nr-CWS can enhance the activation of CD4 + T cells, promote the proliferation of CD4 + T cells and the differentiation of CD4 + T cells to Th1 cells. Copyright © 2017 Elsevier B.V. All rights reserved.

  13. Cytokine production but lack of proliferation in peripheral blood mononuclear cells from chronic Chagas' disease cardiomyopathy patients in response to T. cruzi ribosomal P proteins.

    Directory of Open Access Journals (Sweden)

    Silvia A Longhi

    2014-06-01

    Full Text Available BACKGROUND: Trypanosoma cruzi ribosomal P proteins, P2β and P0, induce high levels of antibodies in patients with chronic Chagas' disease Cardiomyopathy (CCC. It is well known that these antibodies alter the beating rate of cardiomyocytes and provoke apoptosis by their interaction with β1-adrenergic and M2-muscarinic cardiac receptors. Based on these findings, we decided to study the cellular immune response to these proteins in CCC patients compared to non-infected individuals. METHODOLOGY/PRINCIPAL FINDINGS: We evaluated proliferation, presence of surface activation markers and cytokine production in peripheral blood mononuclear cells (PBMC stimulated with P2β, the C-terminal portion of P0 (CP0 proteins and T. cruzi lysate from CCC patients predominantly infected with TcVI lineage. PBMC from CCC patients cultured with P2β or CP0 proteins, failed to proliferate and express CD25 and HLA-DR on T cell populations. However, multiplex cytokine assays showed that these antigens triggered higher secretion of IL-10, TNF-α and GM-CSF by PBMC as well as both CD4+ and CD8+ T cells subsets of CCC subjects. Upon T. cruzi lysate stimulation, PBMC from CCC patients not only proliferated but also became activated within the context of Th1 response. Interestingly, T. cruzi lysate was also able to induce the secretion of GM-CSF by CD4+ or CD8+ T cells. CONCLUSIONS/SIGNIFICANCE: Our results showed that although the lack of PBMC proliferation in CCC patients in response to ribosomal P proteins, the detection of IL-10, TNF-α and GM-CSF suggests that specific T cells could have both immunoregulatory and pro-inflammatory potential, which might modulate the immune response in Chagas' disease. Furthermore, it was possible to demonstrate for the first time that GM-CSF was produced by PBMC of CCC patients in response not only to recombinant ribosomal P proteins but also to parasite lysate, suggesting the value of this cytokine to evaluate T cells responses in T

  14. Inhibitory effects of a selective Jak2 inhibitor on adrenocorticotropic hormone production and proliferation of corticotroph tumor AtT20 cells

    Directory of Open Access Journals (Sweden)

    Asari Y

    2017-09-01

    Full Text Available Yuko Asari, Kazunori Kageyama, Yuki Nakada, Mizuki Tasso, Shinobu Takayasu, Kanako Niioka, Noriko Ishigame, Makoto Daimon Department of Endocrinology and Metabolism, Graduate School of Medicine, Hirosaki University, Hirosaki, Japan Purpose: The primary cause of Cushing’s disease is adrenocorticotropic hormone (ACTH-producing pituitary adenomas. EGFR signaling induces POMC mRNA-transcript levels and ACTH secretion from corticotroph tumors. The Jak–STAT pathway is located downstream of EGFR signaling; therefore, a Jak2 inhibitor could be an effective therapy for EGFR-related tumors. In this study, we determined the effect of a potent and selective Jak2 inhibitor, SD1029, on ACTH production and proliferation in mouse AtT20 corticotroph tumor cells.Materials and methods: AtT20 pituitary corticotroph tumor cells were cultured after transfection with PTTG1- or GADD45β-specific siRNA. Expression levels of mouse POMC, PTTG1, and GADD45β mRNAs were evaluated using quantitative real-time polymerase chain reaction. ACTH levels were measured using ACTH ELISA. Western blot analysis was performed to examine protein expression of phosphorylated STAT3/STAT3. Viable cells and DNA fragmentation were measured using a cell-proliferation assay and cell-death detection ELISA, respectively. Cellular DNA content was analyzed using fluorescence-activated cell sorting.Results: SD1029 decreased POMC and PTTG1 mRNA and ACTH levels, while increasing GADD45β levels. The drug also decreased AtT20-cell proliferation and induced apoptosis, but did not alter cell-cycle progression. SD1029 also inhibited STAT3 phosphorylation. PTTG1 knockdown inhibited POMC mRNA levels and cell proliferation. However, combined treatment with PTTG1 knockdown and SD1029 had no additive effect on POMC mRNA levels or cell proliferation. GADD45β knockdown inhibited the SD1029-induced decrease in POMC mRNA levels and also partially inhibited the decrease in cell proliferation.Conclusion: Both

  15. Biology and clinical application of CAR T cells for B cell malignancies.

    Science.gov (United States)

    Davila, Marco L; Sadelain, Michel

    2016-07-01

    Chimeric antigen receptor (CAR)-modified T cells have generated broad interest in oncology following a series of dramatic clinical successes in patients with chemorefractory B cell malignancies. CAR therapy now appears to be on the cusp of regulatory approval as a cell-based immunotherapy. We review here the T cell biology and cell engineering research that led to the development of second generation CARs, the selection of CD19 as a CAR target, and the preclinical studies in animal models that laid the foundation for clinical trials targeting CD19+ malignancies. We further summarize the status of CD19 CAR clinical therapy for non-Hodgkin lymphoma and B cell acute lymphoblastic leukemia, including their efficacy, toxicities (cytokine release syndrome, neurotoxicity and B cell aplasia) and current management in humans. We conclude with an overview of recent pre-clinical advances in CAR design that argues favorably for the advancement of CAR therapy to tackle other hematological malignancies as well as solid tumors.

  16. Pathogen-expanded CD11b+ invariant NKT cells feedback inhibit T cell proliferation via membrane-bound TGF-β1.

    Science.gov (United States)

    Han, Yanmei; Jiang, Zhengping; Chen, Zhubo; Gu, Yan; Liu, Yanfang; Zhang, Xiang; Cao, Xuetao

    2015-04-01

    Natural killer T cells (NKT cells) are effector cells, but also regulator of immune response, which either promote or suppress immune response through production of different cytokines. However, the subsets of NKT cells with definite phenotype and regulatory function need to be further identified. Furthermore, the mechanisms for NKT cells to regulate immune response remain to be fully elucidated. Here we identified CD11b(+) invariant NKT (CD11b(+) iNKT) cells as a new subset of regulatory NKT cells in mouse models with infection. αGalCer:CD1d complex(+)TCRβ(+)NK1.1(+) NKT cells could be categorized to CD11b(+) and CD11b(-) subsets. NKT cells are enriched in liver. During Listeria monocytogenes infection, hepatic CD11b(+) iNKT cells were significantly induced and expanded, with peak expansion on day 8. CD11b(+) iNKT cells were also expanded significantly in spleen and mesenteric lymph nodes. As compared to CD11b(-) iNKT cells, CD11b(+) iNKT cells expressed higher levels of CD27, FasL, B7H1, CD69, and particularly higher level of membrane-bound TGF-β1 (mTGF-β1), but produced less IFN-γ, IL-4, IL-10 and TGF-β1. Hepatic CD11b(+) iNKT cells suppressed antigen-nonspecific and OVA-specific CD4 and CD8 T cell proliferation through mTGF-β1 both in vitro and in vivo, meanwhile, they did not interfere with activation of CD4 T cells and cytotoxicity of the activated CD8 T cells. Thus, we have identified a new subset of pathogen-expanded CD11b(+) invariant NKT cells which can feedback inhibit T cell response through cell-to-cell contact via cell surface (membrane-bound) TGF-β1, especially at the late stage of immune response against infection. CD11b(+) regulatory iNKT cells may contribute to protect host from pathological injure by preventing immune overactivation. Copyright © 2015 Elsevier Ltd. All rights reserved.

  17. Characterization of the CDR3 structure of the Vβ21 T cell clone in patients with P210(BCR-ABL)-positive chronic myeloid leukemia and B-cell acute lymphoblastic leukemia.

    Science.gov (United States)

    Zha, Xianfeng; Chen, Shaohua; Yang, Lijian; Li, Bo; Chen, Yu; Yan, Xiaojuan; Li, Yangqiu

    2011-10-01

    The clonally expanded T cells identified in most cancer patients that respond to tumor-associated antigen such as P210(BCR-ABL) protein have definite, specific antitumor cytotoxicity. T cell receptor (TCR) Vβ CDR3 repertoire diversity was analyzed in patients with chronic myeloid leukemia (CML) and BCR-ABL(+) B-cell acute lymphoblastic leukemia (B-ALL) by GeneScan. A high frequency of oligoclonal expansion of the TCR Vβ21 subfamily was observed in the peripheral blood of CML and B-ALL patients. These clonally expanded Vβ21 T cells were correlated with the pathophysiologic process of CML. A conserved amino acid motif (SLxxV) was observed within the CDR3 region in only 3 patients with CML. Preferential usage of the Jβ segments was also observed in a minority of patients. The 3-dimensional structures of the CDR3 region containing the same motif or using the same Jβ segment displayed low similarity; on the contrary, the conformation of the CDR3 region containing no conserved motif in some T cell clones was highly similar. In conclusion, our findings indicate a high frequency of TCR Vβ21 subfamily expansion in p210(BCR-ABL)-positive CML and B-ALL patients. The characterization of the CDR3 structure was complex. Regrettably, at this time it was not possible to confirm that the Vβ21 T cell clones were derived from the stimulation of p210(BCR-ABL) protein. Copyright © 2011 American Society for Histocompatibility and Immunogenetics. Published by Elsevier Inc. All rights reserved.

  18. Suppression of T cell-induced osteoclast formation

    Energy Technology Data Exchange (ETDEWEB)

    Karieb, Sahar; Fox, Simon W., E-mail: Simon.fox@plymouth.ac.uk

    2013-07-12

    Highlights: •Genistein and coumestrol prevent activated T cell induced osteoclast formation. •Anti-TNF neutralising antibodies prevent the pro-osteoclastic effect of activated T cells. •Phytoestrogens inhibit T cell derived TNF alpha and inflammatory cytokine production. •Phytoestrogens have a broader range of anti-osteoclastic actions than other anti-resorptives. -- Abstract: Inhibition of T cell derived cytokine production could help suppress osteoclast differentiation in inflammatory skeletal disorders. Bisphosphonates are typically prescribed to prevent inflammatory bone loss but are not tolerated by all patients and are associated with an increased risk of osteonecrosis of the jaw. In light of this other anti-resorptives such as phytoestrogens are being considered. However the effect of phytoestrogens on T cell-induced osteoclast formation is unclear. The effect of genistein and coumestrol on activated T cell-induced osteoclastogenesis and cytokine production was therefore examined. Concentrations of genistein and coumestrol (10{sup −7} M) previously shown to directly inhibit osteoclast formation also suppressed the formation of TRAP positive osteoclast induced by con A activated T cells, which was dependent on inhibition of T cell derived TNF-α. While both reduced osteoclast formation their mechanism of action differed. The anti-osteoclastic effect of coumestrol was associated with a dual effect on con A induced T cell proliferation and activation; 10{sup −7} M coumestrol significantly reducing T cell number (0.36) and TNF-α (0.47), IL-1β (0.23) and IL-6 (0.35) expression, whereas genistein (10{sup −7} M) had no effect on T cell number but a more pronounced effect on T cell differentiation reducing expression of TNF-α (0.49), IL-1β (0.52), IL-6 (0.71) and RANKL (0.71). Phytoestrogens therefore prevent the pro-osteoclastic action of T cells suggesting they may have a role in the control of inflammatory bone loss.

  19. Blockade of CD26-mediated T cell costimulation with soluble caveolin-1-Ig fusion protein induces anergy in CD4{sup +}T cells

    Energy Technology Data Exchange (ETDEWEB)

    Ohnuma, Kei [Department of Rheumatology and Allergy, Research Hospital, The Institute of Medical Science, The University of Tokyo, 4-6-1, Shirokanedai, Minato-ku, Tokyo 108-8639 (Japan); Division of Clinical Immunology, The Advanced Clinical Research Center, The Institute of Medical Science, The University of Tokyo, 4-6-1, Shirokanedai, Minato-ku, Tokyo 108-8639 (Japan); Uchiyama, Masahiko [Department of Rheumatology and Allergy, Research Hospital, The Institute of Medical Science, The University of Tokyo, 4-6-1, Shirokanedai, Minato-ku, Tokyo 108-8639 (Japan); Department of Computational Intelligence and System Science, Tokyo Institute of Technology, 4259 Nagatsuta-cho, Midori-ku, Yokohama, Kanagawa 226-8503 (Japan); Hatano, Ryo; Takasawa, Wataru; Endo, Yuko [Department of Rheumatology and Allergy, Research Hospital, The Institute of Medical Science, The University of Tokyo, 4-6-1, Shirokanedai, Minato-ku, Tokyo 108-8639 (Japan); Dang, Nam H. [Department of Hematologic Malignancies, Nevada Cancer Institute, Las Vegas, NV 89135 (United States); Morimoto, Chikao, E-mail: morimoto@ims.u-tokyo.ac.jp [Department of Rheumatology and Allergy, Research Hospital, The Institute of Medical Science, The University of Tokyo, 4-6-1, Shirokanedai, Minato-ku, Tokyo 108-8639 (Japan); Division of Clinical Immunology, The Advanced Clinical Research Center, The Institute of Medical Science, The University of Tokyo, 4-6-1, Shirokanedai, Minato-ku, Tokyo 108-8639 (Japan)

    2009-08-21

    CD26 binds to caveolin-1 in antigen-presenting cells (APC), and that ligation of CD26 by caveolin-1 induces T cell proliferation in a TCR/CD3-dependent manner. We report herein the effects of CD26-caveolin-1 costimulatory blockade by fusion protein caveolin-1-Ig (Cav-Ig). Soluble Cav-Ig inhibits T cell proliferation and cytokine production in response to recall antigen, or allogeneic APC. Our data hence suggest that blocking of CD26-associated signaling by soluble Cav-Ig may be an effective approach as immunosuppressive therapy.

  20. Effect of IL-2 on recovery of proliferation ability of irradiated T lymphocytes

    International Nuclear Information System (INIS)

    Wang Ninghai; Zhang Lansheng

    1989-01-01

    3 H-thymidine incorporation assay was used to evaluated the proliferation ability of normal human peripheral blood T lymphocytes irradiated with or without exogenous IL-2 by 60 Co γ-ray at various doses after exposure to 1, 2.5, 5, 10, 20 and 40 Gy γ-ray, the DNA synthesis is blocked. It indicated IL-2 has damage effect on the proliferation ability of T cells. 3 H-thymidine incorporation rate in cells decreases with increasing dose of irradiation. Incorporation of 3 H-Tdk in irradiated groups in the dose range of 1 to 40 Gy was compared with that in the control group. The incorporation rate 3 H-TdR in these irradiated groups is 27 to 82 % of that in control group. The inhibition of lymphocyte proliferation was partially enhanced by adding IL-2, but the inhibiting effect on proliferation of human peripheral blood lymphocytes exposed to irradiation at more than 10 Gy is not reversible

  1. Gammadelta receptor bearing T cells in scleroderma: enhanced interaction with vascular endothelial cells in vitro.

    Science.gov (United States)

    Kahaleh, M B; Fan, P S; Otsuka, T

    1999-05-01

    In view of the documented perivascular mononuclear cell infiltration in the involved organs in scleroderma (SSc) and the reported accumulation of gammadelta-T cells in SSc skin and lung, we evaluated gammadelta-T cell interaction with endothelial cells (EC) in vitro. gammadelta- and alphabeta-T cells were isolated from BPMN of SSc patients with early diffuse disease and of matched control subjects by an immunomagnetic method after stimulation with mycobacterium lysate and interleukin-2 for 2 weeks. Lymphocyte adhesion, proliferation, and cytotoxicity to EC were investigated. SSc gammadelta-T cells adhered to cultured EC and proliferated at higher rates than control cells. Furthermore, significant EC cytotoxicity by SSc gammadelta was seen. The cytotoxicity was blocked by addition of anti-gammadelta-TCR antibody and by anti-granzyme A antibody but not by anti-MHC class I and II antibodies. Expression of granzyme A mRNA was seen in five/five SSc gammadelta-T cells and in one/five control cells. alphabeta-T cells from both SSc and control subjects were significantly less interactive with EC than gammadelta-T cells. The data demonstrate EC recognition by SSc gammadelta-T cells and propose gammadelta-T cells as a possible effector cell type in the immune pathogenesis of SSc. Copyright 1999 Academic Press.

  2. Transcriptional Regulation of T-Cell Lipid Metabolism: Implications for Plasma Membrane Lipid Rafts and T-Cell Function

    Directory of Open Access Journals (Sweden)

    George A. Robinson

    2017-11-01

    Full Text Available It is well established that cholesterol and glycosphingolipids are enriched in the plasma membrane (PM and form signaling platforms called lipid rafts, essential for T-cell activation and function. Moreover, changes in PM lipid composition affect the biophysical properties of lipid rafts and have a role in defining functional T-cell phenotypes. Here, we review the role of transcriptional regulators of lipid metabolism including liver X receptors α/β, peroxisome proliferator-activated receptor γ, estrogen receptors α/β (ERα/β, and sterol regulatory element-binding proteins in T-cells. These receptors lie at the interface between lipid metabolism and immune cell function and are endogenously activated by lipids and/or hormones. Importantly, they regulate cellular cholesterol, fatty acid, glycosphingolipid, and phospholipid levels but are also known to modulate a broad spectrum of immune responses. The current evidence supporting a role for lipid metabolism pathways in controlling immune cell activation by influencing PM lipid raft composition in health and disease, and the potential for targeting lipid biosynthesis pathways to control unwanted T-cell activation in autoimmunity is reviewed.

  3. Effect of injection molded micro-structured polystyrene surfaces on proliferation of MC3T3-E1 cells

    Directory of Open Access Journals (Sweden)

    G. Lucchetta

    2015-04-01

    Full Text Available In this work, osteoinductive micro-pillared polystyrene surfaces were mass-produced for bone replacement applications, by means of the micro injection molding process. Firstly, the molding process parameters were optimized with a two-level, three-factor central composite face-centered plan to increase the quality of polystyrene micro pillars replication and to maximize the pillars height uniformity over the molded part. Secondly, osteoblastic MC3T3-E1 cells adhesion and proliferation on the replicated substrates were assessed as a function of micro topography parameters, such as pillars diameter, aspect ratio and spacing. Cell morphology and proliferation were evaluated through MTS test after 1, 3 and 7 days from seeding. The experimental results showed that cells adhesion and proliferation is more positively promoted on micro-pillared surfaces compared to flat surfaces, but no correlations were observed between cell proliferation and pillar diameter and spacing.

  4. CD4+ T regulatory cells from the colonic lamina propria of normal mice inhibit proliferation of enterobacteria-reactive, disease-inducing Th1-cells from scid mice with colitis

    DEFF Research Database (Denmark)

    Gad, M; Brimnes, J; Claesson, Mogens Helweg

    2003-01-01

    Adoptive transfer of CD4+ T cells into scid mice leads to a chronic colitis in the recipients. The transferred CD4+ T cells accumulate in the intestinal lamina propria (LP), express an activated Th1 phenotype and proliferate vigorously when exposed ex vivo to enteric bacterial antigens. As LP CD4......+ T cells from normal BALB/c mice do not respond to enteric bacterial antigens, we have investigated whether colonic LP-derived CD4+ T cells from normal mice suppress the antibacterial response of CD4+ T cells from scid mice with colitis. LP-derived CD4+ T cells cocultured with bone marrow......-derived dendritic cells effectively suppress the antibacterial proliferative response of CD4+ T cells from scid mice with colitis. The majority of these LP T-reg cells display a nonactivated phenotype and suppression is independent of antigen exposure, is partly mediated by soluble factor(s) different from IL-10...

  5. Human hepatitis B viral e antigen and its precursor P20 inhibit T lymphocyte proliferation

    International Nuclear Information System (INIS)

    Purvina, Maija; Hoste, Astrid; Rossignol, Jean-Michel; Lagaudrière-Gesbert, Cécile

    2012-01-01

    Highlights: ► P20, precursor of the HBeAg, interacts with the cellular protein gC1qR. ► HBeAg and P20 bind to T cell surface and inhibit mitogen-induced T cell division. ► HBeAg and P20 inhibition of T cell proliferation is gC1qR and IL-1RAcP-independent. -- Abstract: The hepatitis B virus (HBV) Precore protein is processed through the secretory pathway directly as HBeAg or with the generation of an intermediate (P20). Precore gene has been shown to be implicated in viral persistence, but the functions of HBeAg and its precursors have not been fully elucidated. We show that the secreted proteins HBeAg and P20 interact with T cell surface and alter Kit-225 and primary T cells proliferation, a process which may facilitate the establishment of HBV persistence. Our data indicate that the N-terminal end of Precore is important for these inhibitory effects and exclude that they are dependent on the association of HBeAg and P20 with two characterized cell surface ligands, the Interleukin-1 Receptor Accessory Protein and gC1qR (present study).

  6. Human hepatitis B viral e antigen and its precursor P20 inhibit T lymphocyte proliferation

    Energy Technology Data Exchange (ETDEWEB)

    Purvina, Maija; Hoste, Astrid; Rossignol, Jean-Michel [Universite de Versailles-Saint-Quentin-en-Yvelines, Laboratoire de Genetique et Biologie Cellulaire, EA 4589, 45 avenue des Etats-Unis, 78035 Versailles (France); Lagaudriere-Gesbert, Cecile, E-mail: cecile.lagaudriere-gesbert@u-psud.fr [Universite de Versailles-Saint-Quentin-en-Yvelines, Laboratoire de Genetique et Biologie Cellulaire, EA 4589, 45 avenue des Etats-Unis, 78035 Versailles (France)

    2012-01-27

    Highlights: Black-Right-Pointing-Pointer P20, precursor of the HBeAg, interacts with the cellular protein gC1qR. Black-Right-Pointing-Pointer HBeAg and P20 bind to T cell surface and inhibit mitogen-induced T cell division. Black-Right-Pointing-Pointer HBeAg and P20 inhibition of T cell proliferation is gC1qR and IL-1RAcP-independent. -- Abstract: The hepatitis B virus (HBV) Precore protein is processed through the secretory pathway directly as HBeAg or with the generation of an intermediate (P20). Precore gene has been shown to be implicated in viral persistence, but the functions of HBeAg and its precursors have not been fully elucidated. We show that the secreted proteins HBeAg and P20 interact with T cell surface and alter Kit-225 and primary T cells proliferation, a process which may facilitate the establishment of HBV persistence. Our data indicate that the N-terminal end of Precore is important for these inhibitory effects and exclude that they are dependent on the association of HBeAg and P20 with two characterized cell surface ligands, the Interleukin-1 Receptor Accessory Protein and gC1qR (present study).

  7. 2-(1H-Benzimidazol-2-yl-4,5,6,7-tetrahydro-2H-indazol-3-ol, a Benzimidazole Derivative, Inhibits T Cell Proliferation Involving H+/K+-ATPase Inhibition

    Directory of Open Access Journals (Sweden)

    Jin Liu

    2014-10-01

    Full Text Available In this study, a benzimidazole derivative named BMT-1 is revealed as a potential immunomodulatory agent. BMT-1 inhibits the activity of H+/K+-ATPases from anti-CD3/CD28 activated T cells. Furthermore, inhibition the H+/K+-ATPases by use of BMT-1 should lead to intracellular acidification, inhibiting T cell proliferation. To explore this possibility, the effect of BMT-1 on intracellular pH changes was examined by using BCECF as a pH-dependent fluorescent dye. Interestingly, increases in the pHi were observed in activated T cells, and T cells treated with BMT-1 showed a more acidic intracellular pH. Finally, BMT-1 targeted the H+/K+-ATPases and inhibited the proliferative response of anti-CD3/CD28-stimulated T cells. A cell cycle analysis indicated that BMT-1 arrested the cell cycle progression of activated T cells from the G1 to the S phase without affecting CD25 expression or interleukin-2 (IL-2 production; treating IL-2-dependent PBMCs with BMT-1 also led to the inhibition of cell proliferation. Taken together, these findings demonstrate that BMT-1 inhibits the proliferation of T cells by interfering with H+/K+-ATPases and down-regulating intracellular pHi. This molecule may be an interesting lead compound for the development of new immunomodulatory agents.

  8. Transfer of mRNA Encoding Invariant NKT Cell Receptors Imparts Glycolipid Specific Responses to T Cells and γδT Cells.

    Science.gov (United States)

    Shimizu, Kanako; Shinga, Jun; Yamasaki, Satoru; Kawamura, Masami; Dörrie, Jan; Schaft, Niels; Sato, Yusuke; Iyoda, Tomonori; Fujii, Shin-Ichiro

    2015-01-01

    Cell-based therapies using genetically engineered lymphocytes expressing antigen-specific T cell receptors (TCRs) hold promise for the treatment of several types of cancers. Almost all studies using this modality have focused on transfer of TCR from CD8 cytotoxic T lymphocytes (CTLs). The transfer of TCR from innate lymphocytes to other lymphocytes has not been studied. In the current study, innate and adaptive lymphocytes were transfected with the human NKT cell-derived TCRα and β chain mRNA (the Vα24 and Vβ11 TCR chains). When primary T cells transfected with NKT cell-derived TCR were subsequently stimulated with the NKT ligand, α-galactosylceramide (α-GalCer), they secreted IFN-γ in a ligand-specific manner. Furthermore when γδT cells were transfected with NKT cell-derived TCR mRNA, they demonstrated enhanced proliferation, IFN-γ production and antitumor effects after α-GalCer stimulation as compared to parental γδT cells. Importantly, NKT cell TCR-transfected γδT cells responded to both NKT cell and γδT cell ligands, rendering them bi-potential innate lymphocytes. Because NKT cell receptors are unique and universal invariant receptors in humans, the TCR chains do not yield mispaired receptors with endogenous TCR α and β chains after the transfection. The transfection of NKT cell TCR has the potential to be a new approach to tumor immunotherapy in patients with various types of cancer.

  9. Characterization of activating mutations of NOTCH3 in T-cell acute lymphoblastic leukemia and anti-leukemic activity of NOTCH3 inhibitory antibodies.

    Science.gov (United States)

    Bernasconi-Elias, P; Hu, T; Jenkins, D; Firestone, B; Gans, S; Kurth, E; Capodieci, P; Deplazes-Lauber, J; Petropoulos, K; Thiel, P; Ponsel, D; Hee Choi, S; LeMotte, P; London, A; Goetcshkes, M; Nolin, E; Jones, M D; Slocum, K; Kluk, M J; Weinstock, D M; Christodoulou, A; Weinberg, O; Jaehrling, J; Ettenberg, S A; Buckler, A; Blacklow, S C; Aster, J C; Fryer, C J

    2016-11-24

    Notch receptors have been implicated as oncogenic drivers in several cancers, the most notable example being NOTCH1 in T-cell acute lymphoblastic leukemia (T-ALL). To characterize the role of activated NOTCH3 in cancer, we generated an antibody that detects the neo-epitope created upon gamma-secretase cleavage of NOTCH3 to release its intracellular domain (ICD3), and sequenced the negative regulatory region (NRR) and PEST (proline, glutamate, serine, threonine) domain coding regions of NOTCH3 in a panel of cell lines. We also characterize NOTCH3 tumor-associated mutations that result in activation of signaling and report new inhibitory antibodies. We determined the structural basis for receptor inhibition by obtaining the first co-crystal structure of a NOTCH3 antibody with the NRR protein and defined two distinct epitopes for NRR antibodies. The antibodies exhibit potent anti-leukemic activity in cell lines and tumor xenografts harboring NOTCH3 activating mutations. Screening of primary T-ALL samples reveals that 2 of 40 tumors examined show active NOTCH3 signaling. We also identified evidence of NOTCH3 activation in 12 of 24 patient-derived orthotopic xenograft models, 2 of which exhibit activation of NOTCH3 without activation of NOTCH1. Our studies provide additional insights into NOTCH3 activation and offer a path forward for identification of cancers that are likely to respond to therapy with NOTCH3 selective inhibitory antibodies.

  10. Sepsis-induced alteration in T-cell Ca(2+) signaling in neonatal rats.

    Science.gov (United States)

    Alattar, M H; Ravindranath, T M; Choudhry, M A; Muraskas, J K; Namak, S Y; Dallal, O; Sayeed, M M

    2001-01-01

    Sepsis-induced suppression in T-cell proliferation follows deranged Ca(2+) signaling in adult rats. In preliminary studies, we observed suppression in T-cell proliferation in septic neonatal rats as well. In this study, we assessed splenic T-cell cytosolic Ca(2+) concentration, [Ca(2+)](i), as its elevation plays an important role in T-cell proliferation. Also, we investigated the role of PGE(2) in sepsis-related changes in T-cell [Ca(2+)](i) in animals pretreated with cyclooxygenase-1 (COX-1) inhibitor (resveratrol) and cyclooxygenase-2 (COX-2) inhibitor (NS-398). Sepsis was induced in 15-day-old rat pups by intraperitoneal implantation of fecal pellets containing Escherichia coli and Bacteroides fragilis. The sham group consisted of pups implanted with sterile fecal pellets. Septic and sham pups were sacrificed 24 h after implantation and their spleens were removed. The spleens from sham and septic pups, along with spleens from unoperated control pups, were processed for single cell suspensions, and T cells were isolated using nylon wool columns. Fura-2 fluorophotometry was employed for the measurement of [Ca(2+)](i) (in nM units) in T cells stimulated with concanavalin A (ConA). Our results show that ConA-mediated T-cell [Ca(2+)](i) response is significantly suppressed in septic neonatal rats. Pretreatment of pups with COX-2, but not COX-1 inhibitor, prevented the decrease in the [Ca(2+)](i) response. These findings suggest that PGE(2) might induce the attenuation in T-cell Ca(2+) signaling during sepsis in neonatal rats. Copyright 2001 S. Karger AG, Basel

  11. Effects of PVA-coated nanoparticles on human T helper cell activity.

    Science.gov (United States)

    Strehl, Cindy; Schellmann, Saskia; Maurizi, Lionel; Hofmann-Amtenbrink, Margarethe; Häupl, Thomas; Hofmann, Heinrich; Buttgereit, Frank; Gaber, Timo

    2016-03-14

    Superparamagnetic iron oxide nanoparticles (SPION) are used as high-sensitive enhancer for magnetic resonance imaging, where they represent a promising tool for early diagnosis of destructive diseases such as rheumatoid arthritis (RA). Since we could demonstrate that professional phagocytes are activated by amino-polyvinyl-alcohol-coated-SPION (a-PVA-SPION), the study here focuses on the influence of a-PVA-SPION on human T cells activity. Therefore, primary human CD4+ T cells from RA patients and healthy subjects were treated with varying doses of a-PVA-SPION for 20h or 72h. T cells were then analyzed for apoptosis, cellular energy, expression of the activation marker CD25 and cell proliferation. Although, we observed that T cells from RA patients are more susceptible to low-dose a-PVA-SPION-induced apoptosis than T cells from healthy subjects, in both groups a-PVA-SPION do not activate CD4+ T cells per se and do not influence mitogen-mediated T cells activation with regard to CD25 expression and cell proliferation. Nevertheless, our results demonstrate that CD4+ T cells from RA patients and healthy subjects differ in their response to mitogen stimulation and oxygen availability. We conclude from our data, that a-PVA-SPION do neither activate nor significantly influence mitogen-stimulated CD4+ T cells activation and have negligible influence on T cells apoptosis. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.

  12. High efficacy and safety of low-dose CD19-directed CAR-T cell therapy in 51 refractory or relapsed B acute lymphoblastic leukemia patients.

    Science.gov (United States)

    Pan, J; Yang, J F; Deng, B P; Zhao, X J; Zhang, X; Lin, Y H; Wu, Y N; Deng, Z L; Zhang, Y L; Liu, S H; Wu, T; Lu, P H; Lu, D P; Chang, A H; Tong, C R

    2017-12-01

    Refractory or relapsed B lymphoblastic leukemia (B-ALL) patients have a dismal outcome with current therapy. We treated 42 primary refractory/hematological relapsed (R/R) and 9 refractory minimal residual disease by flow cytometry (FCM-MRD + ) B-ALL patients with optimized second generation CD19-directed CAR-T cells. The CAR-T-cell infusion dosages were initially ranged from 0.05 to 14 × 10 5 /kg and were eventually settled at 1 × 10 5 /kg for the most recent 20 cases. 36/40 (90%) evaluated R/R patients achieved complete remission (CR) or CR with incomplete count recovery (CRi), and 9/9 (100%) FCM-MRD + patients achieved MRD - . All of the most recent 20 patients achieved CR/CRi. Most cases only experienced mild to moderate CRS. 8/51 cases had seizures that were relieved by early intervention. Twenty three of twenty seven CR/CRi patients bridged to allogeneic hematopoietic stem cell transplantation (allo-HCT) remained in MRD - with a median follow-up time of 206 (45-427) days, whereas 9 of 18 CR/CRi patients without allo-HCT relapsed. Our results indicate that a low CAR-T-cell dosage of 1 × 10 5 /kg, is effective and safe for treating refractory or relapsed B-ALL, and subsequent allo-HCT could further reduce the relapse rate.

  13. Kefir induces cell-cycle arrest and apoptosis in HTLV-1-negative malignant T-lymphocytes

    Directory of Open Access Journals (Sweden)

    Katia Maalouf

    2011-02-01

    Full Text Available Katia Maalouf1, Elias Baydoun2, Sandra Rizk11Department of Natural Sciences, Lebanese American University, Beirut, Lebanon; 2Department of Biology, American University of Beirut, Beirut, LebanonBackground: Adult lymphoblastic leukemia (ALL is a malignancy that occurs in white blood cells. The overall cure rate in children is 85%, whereas it is only 40% in adults. Kefir is an important probiotic that contains many bioactive ingredients, which give it unique health benefits. It has been shown to control several cellular types of cancer.Purpose: The present study investigates the effect of a cell-free fraction of kefir on CEM and Jurkat cells, which are human T-lymphotropic virus type I (HTLV-1-negative malignant T-lymphocytes.Methods: Cells were incubated with different kefir concentrations. The cytotoxicity of the compound was evaluated by determining the percentage viability of cells. The effect of all the noncytotoxic concentrations of kefir on the proliferation of CEM and Jurkat cells was then assessed. The levels of transforming growth factor-alpha (TGF-α, transforming growth factor- beta1 (TGF-β1, matrix metalloproteinase-2 (MMP-2, and MMP-9 mRNA upon kefir treatment were then analyzed using reverse transcriptase polymerase chain reaction (RT-PCR. Finally, the growth inhibitory effects of kefir on cell-cycle progression/apoptosis were assessed by Cell Death Detection (ELISA and flow cytometry.Results: The maximum cytotoxicity recorded after 48-hours treatment with 80 µg/µL kefir was only 42% and 39% in CEM and Jurkat cells, respectively. The percent reduction in proliferation was very significant, and was dose-, and time-dependent. In both cell lines, kefir exhibited its antiproliferative effect by downregulating TGF-α and upregulating TGF- β1 mRNA expression. Upon kefir treatment, a marked increase in cell-cycle distribution was noted in the preG1 phase of CEM and Jurkat cells, indicating the proapoptotic effect of kefir, which was

  14. A noncognate interaction with anti-receptor antibody-activated helper T cells induces small resting murine B cells to proliferate and to secrete antibody

    DEFF Research Database (Denmark)

    Owens, T

    1988-01-01

    on resting B cells (even in the presence of intact F23.1 antibody), but could induce antibody secretion by anti-Ig-preactivated B cells. Both F23.1+ clones (E9.D4 and 4.35F2) and one F23.1- clone (D2.2) could synergize with supernatants from activated E9.D4 T cells to induce B cell activation. F(ab')2......Culture of small resting allogeneic B cells (of an irrelevant haplotype) with two clones of T helper (Th) cells that were activated by the F23.1 anti-T cell receptor antibody led to the activation of B cells to proliferate and to secrete antibody. Th cell supernatants by themselves had no effect...... fragments of F23.1 induced E9.D4 to activate B cells as efficiently as intact F23.1 and B cell populations that had been incubated with F23.1 were not activated when cultured with E9.D4, although T cells recognized cell-presented F23.1 and were weakly activated. Reduction of the density of F23.1 adsorbed...

  15. Methotrexate induces poly(ADP-ribose) polymerase-dependent, caspase 3-independent apoptosis in subsets of proliferating CD4+ T cells

    DEFF Research Database (Denmark)

    Nielsen, C H; Albertsen, L; Bendtzen, K

    2007-01-01

    The mechanism of action of methotrexate (MTX) in autoimmune diseases (AID) is unclear. A pro-apoptotic effect has been demonstrated in mitogen-stimulated peripheral blood mononuclear cells (PBMC), but studies employing conventional antigens have disputed a pro-apoptotic effect. CD4+ T helper (Th....... Exposure of CA-stimulated PBMC to MTX significantly increased their level of cleaved poly(ADP-ribose) polymerase (PARP), and a similar tendency was observed in TT-stimulated cells. Unlike CA and TT, the mitogen phytohaemagglutinin (PHA) induced proliferation of both CD4- and CD4+ T cells, and induced......) cells play a significant role in most AID. We therefore examined directly, by flow cytometry, the uptake of MTX by the T helper (Th) cells stimulated for 6 days with Candida albicans (CA) or tetanus toxoid (TT), and its consequences with respect to induction of apoptosis. While none of the resting Th...

  16. Control of amino acid transport coordinates metabolic reprogramming in T-cell malignancy.

    Science.gov (United States)

    Grzes, K M; Swamy, M; Hukelmann, J L; Emslie, E; Sinclair, L V; Cantrell, D A

    2017-12-01

    This study explores the regulation and importance of System L amino acid transport in a murine model of T-cell acute lymphoblastic leukemia (T-ALL) caused by deletion of phosphatase and tensin homolog deleted on chromosome 10 (PTEN). There has been a strong focus on glucose transport in leukemias but the present data show that primary T-ALL cells have increased transport of multiple nutrients. Specifically, increased leucine transport in T-ALL fuels mammalian target of rapamycin complex 1 (mTORC1) activity which then sustains expression of hypoxia inducible factor-1α (HIF1α) and c-Myc; drivers of glucose metabolism in T cells. A key finding is that PTEN deletion and phosphatidylinositol (3,4,5)-trisphosphate (PtdIns(3,4,5)P 3 ) accumulation is insufficient to initiate leucine uptake, mTORC1 activity, HIF1α or c-Myc expression in T cells and hence cannot drive T-ALL metabolic reprogramming. Instead, a key regulator for leucine transport in T-ALL is identified as NOTCH. Mass spectrometry based proteomics identifies SLC7A5 as the predominant amino acid transporter in primary PTEN -/- T-ALL cells. Importantly, expression of SLC7A5 is critical for the malignant transformation induced by PTEN deletion. These data reveal the importance of regulated amino acid transport for T-cell malignancies, highlighting how a single amino acid transporter can have a key role.

  17. Performance-enhancing drugs: design and production of redirected chimeric antigen receptor (CAR) T cells.

    Science.gov (United States)

    Levine, B L

    2015-03-01

    Performance enhancement of the immune system can now be generated through ex vivo gene modification of T cells in order to redirect native specificity to target tumor antigens. This approach combines the specificity of antibody therapy, the expanded response of cellular therapy and the memory activity of vaccine therapy. Recent clinical trials of chimeric antigen receptor (CAR) T cells directed toward CD19 as a stand-alone therapy have shown sustained complete responses in patients with acute lymphoblastic leukemia and chronic lymphocytic leukemia. As these drug products are individually derived from a patient's own cells, a different manufacturing approach is required for this kind of personalized therapy compared with conventional drugs. Key steps in the CAR T-cell manufacturing process include the selection and activation of isolated T cells, transduction of T cells to express CARs, ex vivo expansion of modified T cells and cryopreservation in infusible media. In this review, the steps involved in isolating, genetically modifying and scaling-out the CAR T cells for use in a clinical setting are described in the context of in-process and release testing and regulatory standards.

  18. Demonstration of strong enterobacterial reactivity of CD4+CD25- T cells from conventional and germ-free mice which is counter-regulated by CD4+CD25+ T cells

    DEFF Research Database (Denmark)

    Gad, Monika; Pedersen, Anders Elm; Kristensen, Nanna N

    2004-01-01

    Unfractionated CD4+ T cells from the gut-associated lymphoid tissue (GALT) and peripheral lymph nodes are unresponsive when exposed to enterobacterial antigens in vitro. Under similar conditions, CD4+ T cells depleted in vivo or in vitro of CD4+CD25+ T cells proliferate extensively. The CD4+CD25- T...

  19. STAT3-mediated constitutive expression of SOCS-3 in cutaneous T-cell lymphoma

    DEFF Research Database (Denmark)

    Brender, C; Nielsen, M; Kaltoft, K

    2001-01-01

    ) obtained from affected skin from a patient with mycosis fungoides (MF) and from peripheral blood from a patient with Sezary syndrome (SS). In contrast, constitutive SOCS-3 expression is not found in the leukemic Jurkat T-cell line, the MOLT-4 acute lymphoblastic leukemia cell line, and the monocytic......, it has been hypothesized that an aberrant SOCS expression plays a role in neoplastic transformation. This study reports on a constitutive SOCS-3 expression in cutaneous T-cell lymphoma (CTCL) cell lines. SOCS-3 protein is constitutively expressed in tumor cell lines (but not in nonmalignant T cells...... leukemic cell line U937. Expression of SOCS-3 coincides with a constitutive activation of STAT3 in CTCL tumor cells, and stable transfection of CTCL tumor cells with a dominant negative STAT3 strongly inhibits SOCS-3 expression, whereas transfection with wild-type STAT3 does not. Moreover, the reduced SOCS...

  20. Clinical Significance of Immuno phenotypic Markers in Pediatric T-cell Acute Lymphoblastic Leukemia

    International Nuclear Information System (INIS)

    SIDHOM, I.; SHAABAN, Kh.; SOLIMAN, S.; HAMDY, N.; YASSIN, D.; SALEM, Sh.; HASSANEIN, H.; MANSOUR, M.T.; EZZAT, S.; EL-ANWAR, W.

    2008-01-01

    Background: Cell-marker profiling has led to conflicting conclusions about its prognostic significance in T-ALL. Aim: To investigate the prevalence of the expression of CD34, CD10 and myeloid associated antigens (CD13/ CD33) in childhood T-ALL and to relate their presence to initial clinical and biologic features and early response to therapy. Patients and Methods: This study included 67 consecutive patients with newly diagnosed T-ALL recruited from the Children's Cancer Hospital in Egypt during the time period from July 2007 to June 2008. Immuno phenotypic markers and minimal residual disease (MRD) were studied by five-color flow cytometry. Results: The frequency of CD34 was 34.9%, CD10 33.3%, while CD13/CD33 was 18.8%. No significant association was encountered between CD34, CD10 or myeloid antigen positivity and the presenting clinical features as age, sex, TLC and CNS leukemia. Only CD10+ expression had significant association with initial CNS involvement (p=0.039). CD34 and CD13/CD33 expression was significantly associated with T-cell maturation stages (p<0.05). No relationship was observed for age, TLC, gender, NCI risk or CNS involvement with early response to therapy illustrated by BM as well as MRD day 15 and day 42. CD34+, CD13/CD33+ and early T-cell stage had high MRD levels on day 15 that was statistically highly significant (p<0.01), but CD10+ had statistically significant lower MRD level on day 15 (p=0.049). However, only CD34 retained its significance at an MRD cut-off level of 0.01%. Conclusion: CD34, CD10, CD13/CD33 expression, as well as T-cell maturation stages, may have prognostic significance in pediatric T-ALL as they have a significant impact on early clearance of leukemic cells detected by MRD day 15.

  1. ImmunoPET Imaging of Murine CD4+ T Cells Using Anti-CD4 Cys-Diabody: Effects of Protein Dose on T Cell Function and Imaging.

    Science.gov (United States)

    Freise, Amanda C; Zettlitz, Kirstin A; Salazar, Felix B; Lu, Xiang; Tavaré, Richard; Wu, Anna M

    2017-08-01

    Molecular imaging of CD4 + T cells throughout the body has implications for monitoring autoimmune disease and immunotherapy of cancer. Given the key role of these cells in regulating immunity, it is important to develop a biologically inert probe. GK1.5 cys-diabody (cDb), a previously developed anti-mouse CD4 antibody fragment, was tested at different doses to assess its effects on positron emission tomography (PET) imaging and CD4 + T cell viability, proliferation, CD4 expression, and function. The effect of protein dose on image contrast (lymphoid tissue-to-muscle ratio) was assessed by administering different amounts of 89 Zr-labeled GK1.5 cDb to mice followed by PET imaging and ex vivo biodistribution analysis. To assess impact of GK1.5 cDb on T cell biology, GK1.5 cDb was incubated with T cells in vitro or administered intravenously to C57BL/6 mice at multiple protein doses. CD4 expression and T cell proliferation were analyzed with flow cytometry and cytokines were assayed. For immunoPET imaging, the lowest protein dose of 2 μg of 89 Zr-labeled GK1.5 cDb resulted in significantly higher % injected dose/g in inguinal lymph nodes (ILN) and spleen compared to the 12-μg protein dose. In vivo administration of GK1.5 cDb at the high dose of 40 μg caused a transient decrease in CD4 expression in spleen, blood, lymph nodes, and thymus, which recovered within 3 days postinjection; this effect was reduced, although not abrogated, when 2 μg was administered. Proliferation was inhibited in vivo in ILN but not the spleen by injection of 40 μg GK1.5 cDb. Concentrations of GK1.5 cDb in excess of 25 nM significantly inhibited CD4 + T cell proliferation and interferon-γ production in vitro. Overall, using low-dose GK1.5 cDb minimized biological effects on CD4 + T cells. Low-dose GK1.5 cDb yields high-contrast immunoPET images with minimal effects on T cell biology in vitro and in vivo and may be a useful tool for investigating CD4 + T cells in the context of

  2. Selection and characterization of T-cell variants lacking molecules involved in T-cell activation (T3 T-cell receptor, T44, and T11): analysis of the functional relationship among different pathways of activation

    International Nuclear Information System (INIS)

    Moretta, A.; Poggi, A.; Olive, D.; Bottino, C.; Fortis, C.; Pantaleo, G.; Moretta, L.

    1987-01-01

    A clone of the interleukin 2-producing Jurkat leukemia cell line termed JA3 (surface phenotype, T3 + , Ti + , T44 + , T11 + , T40 + ) has been used to induce and select cell variants lacking surface molecules involved in T-cell activation. Following 200 rad of γ-radiation (1 rad = 0.01 Gy), cells were treated with monoclonal antibodies (mAbs) directed to T3, Ti, T44, or T11 antigen and complement. After growth of the residual cells in culture, negative cells were cloned under limiting conditions. Depending on the specificity of the mAb used for the immunoselection, three groups of variants were obtained. (i) The use of mAbs directed to T3 or Ti resulted in cell variants that expressed the T3 - Ti - T44 + Leu1 + T11 + T40 + 4F2 + HLA class I + surface phenotype. (ii) Immunoselection with anti-T44 mAb resulted in 2 variants that shared the T3 - Ti - T44 - Leu1 - T11 - T40 - 4F2 - HLA class I + phenotype. (iii) Cell treatment with anti-T11 mAb resulted in 15 variants characterized by the lack of T11 antigen expression and of all the other T-cell-specific surface antigens. Therefore, it appears that the different sets of JA3 cell variants, like T cells at discrete stages of intrathymic differentiation, may follow a coordinated expression of surface differentiation antigens. Analysis of the functional responsiveness of the three distinct groups of JA3 cell variants to different stimuli showed that all produced interleukin 2 in response to A23187 calcium ionophore plus phorbol 12-myristate 13-acetate

  3. Approved CAR T cell therapies : Ice bucket challenges on glaring safety risks and long-term impacts

    NARCIS (Netherlands)

    P.P. Zheng (Pingpin); J.M. Kros (Johan); J. Li (Jin)

    2018-01-01

    textabstractTwo autologous chimeric antigen receptor (CAR) T cell therapies (Kymriah™ and Yescarta™) were recently approved by the FDA. Kymriah™ is for the treatment of pediatric patients and young adults with refractory or relapse (R/R) B cell precursor acute lymphoblastic leukemia and Yescarta™ is

  4. Rearrangements of genes for the antigen receptor on T cells as markers of lineage and clonality in human lymphoid neoplasms.

    Science.gov (United States)

    Waldmann, T A; Davis, M M; Bongiovanni, K F; Korsmeyer, S J

    1985-09-26

    The T alpha and T beta chains of the heterodimeric T-lymphocyte antigen receptor are encoded by separated DNA segments that recombine during T-cell development. We have used rearrangements of the T beta gene as a widely applicable marker of clonality in the T-cell lineage. We show that the T beta genes are used in both the T8 and T4 subpopulations of normal T cells and that Sézary leukemia, adult T-cell leukemia, and the non-B-lineage acute lymphoblastic leukemias are clonal expansions of T cells. Furthermore, circulating T cells from a patient with the T8-cell-predominantly lymphocytosis associated with granulocytopenia are shown to be monoclonal. Finally, the sensitivity and specificity of this tumor-associated marker have been exploited to monitor the therapy of a patient with adult T-cell leukemia. These unique DNA rearrangements provide insights into the cellular origin, clonality, and natural history of T-cell neoplasia.

  5. Low CD4/CD8 T-cell ratio associated with inflammatory arthropathy in human T-cell leukemia virus type I Tax transgenic mice.

    Directory of Open Access Journals (Sweden)

    Takeo Ohsugi

    Full Text Available BACKGROUND: Human T-cell leukemia virus type I (HTLV-1 can cause an aggressive malignancy known as adult T-cell leukemia/lymphoma (ATL as well as inflammatory diseases such as HTLV-1-associated myelopathy/tropical spastic paraparesis (HAM/TSP. A transgenic mouse that expresses HTLV-1 Tax also develops T-cell leukemia/lymphoma and an inflammatory arthropathy that resembles rheumatoid arthritis. The aim of this study was to identify the primary T-cell subsets involved in the development of arthropathy in Tax transgenic mice. PRINCIPAL FINDINGS: By 24 months of age, Tax transgenic mice developed severe arthropathy with a cumulative incidence of 22.8%. The pathological findings of arthropathy in Tax transgenic mice were similar to those seen in human rheumatoid arthritis or mouse models of rheumatoid arthritis, with synovial proliferation and a positive rheumatoid factor. Before the onset of spontaneous arthropathy, young and old Tax transgenic mice were not sensitive to collagen and did not develop arthritis after immunization with type II collagen. The arthropathic Tax transgenic mice showed a significantly decreased proportion of splenic CD4(+ T cells, whereas the proportion of splenic CD8(+ T cells was increased. Regulatory T cells (CD4(+CD25(+Foxp3(+ were significantly decreased and CD8(+ T cells that expressed the chemokine receptor CCR4 (CD8(+CCR4(+ were significantly increased in arthropathic Tax transgenic mice. The expression of tax mRNA was strong in the spleen and joints of arthropathic mice, with a 40-fold increase compared with healthy transgenic mice. CONCLUSIONS: Our findings reveal that Tax transgenic mice develop rheumatoid-like arthritis with proliferating synovial cells in the joints; however, the proportion of different splenic T-cell subsets in these mice was completely different from other commonly used animal models of rheumatoid arthritis. The crucial T-cell subsets in arthropathic Tax transgenic mice appear to resemble

  6. The timing of T cell priming and cycling

    Directory of Open Access Journals (Sweden)

    Reinhard eObst

    2015-11-01

    Full Text Available The proliferation of specific lymphocytes is the central tenet of the clonal selection paradigm. Antigen recognition by T cells triggers a series of events that produces expanded clones of differentiated effector cells. TCR signaling events are detectable within seconds and minutes and are likely to continue for hours and days in vivo. Here, I review the work done on the importance of TCR signals in the later part of the expansion phase of the primary T cell response, primarily regarding the regulation of the cell cycle in CD4+ and CD8+ cells. The results suggest a degree of programming by early signals for effector differentiation, particularly in the CD8+ T cell compartment, with optimal expansion supported by persistent antigen presentation later on. Differences to CD4+ T cell expansion and new avenues towards a molecular understanding of cell cycle regulation in lymphocytes are discussed.

  7. Effects of burn with and without Escherichia coli infection in rats on intestinal vs. splenic T-cell responses.

    Science.gov (United States)

    Ravindranath, T; Al-Ghoul, W; Namak, S; Fazal, N; Durazo-Arvizu, R; Choudhry, M; Sayeed, M M

    2001-12-01

    To evaluate the effect of burn injury with and without an Escherichia coliseptic complication on T-cell proliferation, interleukin-2 production, and Ca(2+) signaling responses in intestinal Peyer's patch and splenic T cells. Prospective, randomized, sham-controlled animal study. University medical center research laboratory. Adult male Sprague-Dawley rats. Rats were subjected to a 30% total body surface area, full skin thickness burn. Infection in rats was induced via intraperitoneal inoculation of E. coli, 10(9) colony forming units/kg, with or without a prior burn. Rat Peyer's patch and splenic T lymphocytes were isolated by using a nylon wool cell purification protocol. T-cell proliferation, interleukin-2 production, and Ca(2+) signaling responses were measured after stimulation of cells with the mitogen, concanavalin A. T-cell proliferation was determined by measuring incorporation of (3)H-thymidine into T-cell cultures. Interleukin-2 production by T-cell cultures was measured by using enzyme-linked immunosorbent assay. Intracellular T-cell Ca2(+ )concentration, [Ca(2+)](i), was measured by the use of Ca(2+)-specific fluorescent label, fura-2, and its fluorometric quantification. [Ca(2+)](i) was also evaluated by the use of digital video imaging of fura-2 loaded individual T cells. T-cell proliferation and interleukin-2 production were suppressed substantially in both Peyer's patch and splenic T cells 3 days after either the initial burn alone or burn followed by the E. coli inoculation at 24 hrs after the initial burn. There seemed to be no demonstrable additive effects of E. coli infection on the effects produced by burn injury alone. The T-cell proliferation and interleukin-2 production suppressions with burn or burn-plus-infection insults were correlated with attenuated Ca(2+) signaling. E. coli infection alone suppressed T-cell proliferation in Peyer's patch but not in splenic T cells at 2 days postbacterial inoculation; E. coli infection had no effect on

  8. Self-recognition specificity expressed by T cells from nude mice. Absence of detectable Ia-restricted T cells in nude mice that do exhibit self-K/D-restricted T cell responses

    International Nuclear Information System (INIS)

    Kruisbeek, A.M.; Davis, M.L.; Matis, L.A.; Longo, D.L.

    1984-01-01

    The presence in athymic nude mice of precursor T cells with self-recognition specificity for either H-2 K/D or H-2 I region determinants was investigated. Chimeras were constructed of lethally irradiated parental mice receiving a mixture of F1 nude mouse (6-8 wk old) spleen and bone marrow cells. The donor inoculum was deliberately not subjected to any T cell depletion procedure, so that any potential major histocompatibility complex-committed precursor T cells were allowed to differentiate and expand in the normal parental recipients. 3 mo after reconstitution, the chimeras were immunized with several protein antigens in complete Freund's adjuvant in the footpads and their purified draining lymph node T cells tested 10 d later for ability to recognize antigen on antigen-presenting cells of either parental haplotype. Also, their spleen and lymph node cells were tested for ability to generate a cytotoxic T lymphocyte (CTL) response to trinitrophenyl (TNP)-modified stimulator cells of either parental haplotype. It was demonstrated that T cell proliferative responses of these F1(nude)----parent chimeras were restricted solely to recognizing parental host I region determinants as self and expressed the Ir gene phenotype of the host. In contrast, CTL responses could be generated (in the presence of interleukin 2) to TNP-modified stimulator cells of either parental haplotype. Thus these results indicate that nude mice which do have CTL with self-specificity for K/D region determinants lack proliferating T cells with self-specificity for I region determinants. These results provide evidence for the concepts that development of the I region-restricted T cell repertoire is strictly an intrathymically determined event and that young nude mice lack the unique thymic elements responsible for education of I region-restricted T cells

  9. Flow-cytometric measurement of CD4-8- T cells bearing T-cell receptor αβ chains, 1

    International Nuclear Information System (INIS)

    Kusunoki, Yoichiro; Hirai, Yuko; Kyoizumi, Seishi; Akiyama, Mitoshi.

    1992-09-01

    In this study we detected rare, possibly abnormal, T cells bearing CD3 surface antigen and T-cell receptor (TCR) αβ chains but lacking both CD4 and CD8 antigens (viz., TCRαβ + CD4 - 8 - cells, as determined by flow cytometry). The TCRαβ + CD4 - 8 - T cells were detected at a mean frequency of 0.63 ± 0.35 % (mean ± standard deviation) in peripheral blood TCRαβ + cells of 119 normal persons. Two unusual cases besides the 119 normal persons showed extremely elevated frequencies of TCRαβ + CD4 - 8 - T cells, viz., approximately 5 % to 10 % and 14 % to 19 % in whole TCRαβ + cells. Both individuals were males who were otherwise physiologically quite normal with no history of severe illness, and these high frequencies were also observed in blood samples collected 2 or 8 years prior to the current measurements. The TCRαβ + CD4 - 8 - T cells of the two individuals were found to express mature T-cell markers such as CD2,3, and 5 antigens, as well as natural killer (NK) cell markers, viz., CD11b, 16, 56, and 57 antigens, when peripheral blood lymphocytes were subjected to three-color flow cytometry. Lectin-dependent or redirected antibody-dependent cell-mediated cytotoxicities were observed for both freshly sorted TCRαβ + CD4 - 8 - cells and in vitro established clones. Nevertheless, NK-like activity was not detected. Further, Southern blot analysis of TCRβ and γ genes revealed identical rearrangement patterns for all the TCRαβ + CD4 - 8 - clones established in vitro. These results suggest that the TCRαβ + CD4 - 8 - T cells from these two mean exhibit unique characteristics and proliferate clonally in vivo. (author)

  10. Reactivity of inducer cell subsets and T8-cell activation during the human autologous mixed lymphocyte reaction.

    Science.gov (United States)

    Romain, P L; Morimoto, C; Daley, J F; Palley, L S; Reinherz, E L; Schlossman, S F

    1984-01-01

    To characterize the responding T cells in the autologous mixed lymphocyte reaction (AMLR), T cells were fractionated into purified subpopulations employing monoclonal antibodies and a variety of separation techniques including fluorescence-activated cell sorting. It was found that isolated T4 cells, but not T8 cells, proliferated in response to autologous non-T cells. More importantly, within the T4 subset, the autoreactive population was greatly enriched in a fraction reactive with an autoantibody from patients with juvenile chronic arthritis (JRA) or the monoclonal antibody anti-TQ1. Although T8 cells themselves were unable to proliferate in the AMLR, they could be induced to respond in the presence of either T4 cells or exogenous IL-2 containing medium. This was demonstrated by direct measurement of tritiated thymidine uptake by T8 cells during the course of the AMLR as well as by analysis of their relative DNA content. Taken together, these data indicate that the AMLR represents a complex pattern of immune responsiveness distinct from that observed in response to soluble antigen or alloantigen. The precise function of this T-cell circuit remains to be determined.

  11. PDZ binding motif of HTLV-1 Tax promotes virus-mediated T-cell proliferation in vitro and persistence in vivo.

    Science.gov (United States)

    Xie, Li; Yamamoto, Brenda; Haoudi, Abdelali; Semmes, O John; Green, Patrick L

    2006-03-01

    HTLV-1 cellular transformation and disease induction is dependent on expression of the viral Tax oncoprotein. PDZ is a modular protein interaction domain used in organizing signaling complexes in eukaryotic cells through recognition of a specific binding motif in partner proteins. Tax-1, but not Tax-2, contains a PDZ-binding domain motif (PBM) that promotes the interaction with several cellular PDZ proteins. Herein, we investigate the contribution of the Tax-1 PBM in HTLV-induced proliferation and immortalization of primary T cells in vitro and viral survival in an infectious rabbit animal model. We generated several HTLV-1 and HTLV-2 Tax viral mutants, including HTLV-1deltaPBM, HTLV-2+C22(+PBM), and HTLV-2+ C18(deltaPBM). All Tax mutants maintained the ability to significantly activate the CREB/ATF or NFkappaB signaling pathways. Microtiter proliferation assays revealed that the Tax-1 PBM significantly increases both HTLV-1- and HTLV-2-induced primary T-cell proliferation. In addition, Tax-1 PBM was responsible for the micronuclei induction activity of Tax-1 relative to that of Tax-2. Viral infection and persistence were severely attenuated in rabbits inoculated with HTLV-1deltaPBM. Our results provide the first direct evidence suggesting that PBM-mediated associations between Tax-1 and cellular proteins play a key role in HTLV-induced cell proliferation and genetic instability in vitro and facilitate viral persistence in vivo.

  12. 1Protein Energy Malnutrition Impairs Homeostatic Proliferation of Memory CD8 T cells

    Science.gov (United States)

    Iyer, Smita S.; Chatraw, Janel Hart; Tan, Wendy G.; Wherry, E. John; Becker, Todd C.; Ahmed, Rafi; Kapasi, Zoher F.

    2011-01-01

    Nutrition is a critical but poorly understood determinant of immunity. There is abundant epidemiological evidence linking protein malnutrition to impaired vaccine efficacy and increased susceptibility to infections; yet, the role of dietary protein in immune memory homeostasis remains poorly understood. Here we show that protein energy malnutrition (PEM) induced in mice by low-protein (LP) feeding has a detrimental impact on CD8 memory. Relative to adequate-protein (AP) fed controls, LP feeding in lymphocytic choriomeningitis virus (LCMV) immune mice resulted in a 2-fold decrease in LCMV-specific CD8 memory T cells. Adoptive transfer of memory cells, labeled with a division tracking dye, from AP mice into naive LP or AP mice demonstrated that PEM caused profound defects in homeostatic proliferation. Remarkably, this defect occurred despite the lymphopenic environment in LP hosts. While antigen-specific memory cells in LP and AP hosts were phenotypically similar, memory cells in LP hosts were markedly less-responsive to poly(I:C)-induced acute proliferative signals. Furthermore, upon recall, memory cells in LP hosts displayed reduced proliferation and protection from challenge with LCMV-clone 13 resulting in impaired viral clearance in the liver. The findings show a metabolic requirement of dietary protein in sustaining functional CD8 memory and suggest that interventions to optimize dietary protein intake may improve vaccine efficacy in malnourished individuals. PMID:22116826

  13. Hormonal control of T-cell development in health and disease.

    Science.gov (United States)

    Savino, Wilson; Mendes-da-Cruz, Daniella Arêas; Lepletier, Ailin; Dardenne, Mireille

    2016-02-01

    The physiology of the thymus, the primary lymphoid organ in which T cells are generated, is controlled by hormones. Data from animal models indicate that several peptide and nonpeptide hormones act pleiotropically within the thymus to modulate the proliferation, differentiation, migration and death by apoptosis of developing thymocytes. For example, growth hormone and prolactin can enhance thymocyte proliferation and migration, whereas glucocorticoids lead to the apoptosis of these developing cells. The thymus undergoes progressive age-dependent atrophy with a loss of cells being generated and exported, therefore, hormone-based therapies are being developed as an alternative strategy to rejuvenate the organ, as well as to augment thymocyte proliferation and the export of mature T cells to peripheral lymphoid organs. Some hormones (such as growth hormone and progonadoliberin-1) are also being used as therapeutic agents to treat immunodeficiency disorders associated with thymic atrophy, such as HIV infection. In this Review, we discuss the accumulating data that shows the thymus gland is under complex and multifaceted hormonal control that affects the process of T-cell development in health and disease.

  14. T-cell prolymphocytic leukemia

    OpenAIRE

    Graham, Robbie L.; Cooper, Barry; Krause, John R.

    2013-01-01

    T-cell prolymphocytic leukemia is a rare and unusual malignancy characterized by the proliferation of small- to medium-sized prolymphocytes of postthymic origin with distinctive clinical, morphologic, immunophenotypic, and cytogenetic features. Involvement of the peripheral blood, bone marrow, lymph nodes, liver, spleen, and skin can occur. The clinical course is typically very aggressive with poor response to conventional chemotherapy and short survival rates, and the only potential long-ter...

  15. HTLV-1 Alters T Cells for Viral Persistence and Transmission

    Directory of Open Access Journals (Sweden)

    Azusa Tanaka

    2018-03-01

    Full Text Available Human T-cell leukemia virus type 1 (HTLV-1 was the first retrovirus to be discovered as a causative agent of adult T-cell leukemia-lymphoma (ATL and chronic inflammatory diseases. Two viral factors, Tax and HTLV-1 bZIP factor (HBZ, are thought to be involved in the leukemogenesis of ATL. Tax expression is frequently lost due to DNA methylation in the promoter region, genetic changes to the tax gene, and deletion of the 5′ long terminal repeat (LTR in approximately half of all ATL cases. On the other hand, HBZ is expressed in all ATL cases. HBZ is known to function in both protein form and mRNA form, and both forms play an important role in the oncogenic process of HTLV-1. HBZ protein has a variety of functions, including the suppression of apoptosis, the promotion of proliferation, and the impairment of anti-viral activity, through the interaction with several host cellular proteins including p300/CBP, Foxp3, and Foxo3a. These functions dramatically modify the transcriptional profiling of host T cells. HBZ mRNA also promotes T cell proliferation and viability. HBZ changes infected T cells to CCR4+TIGIT+CD4+ effector/memory T cells. This unique immunophenotype enables T cells to migrate into various organs and tissues and to survive in vivo. In this review, we summarize how HBZ hijacks the transcriptional networks and immune systems of host T cells to contribute to HTLV-1 pathogenesis on the basis of recent new findings about HBZ and tax.

  16. CAR T cell therapy for breast cancer: harnessing the tumor milieu to drive T cell activation.

    Science.gov (United States)

    Bajgain, Pradip; Tawinwung, Supannikar; D'Elia, Lindsey; Sukumaran, Sujita; Watanabe, Norihiro; Hoyos, Valentina; Lulla, Premal; Brenner, Malcolm K; Leen, Ann M; Vera, Juan F

    2018-05-10

    The adoptive transfer of T cells redirected to tumor via chimeric antigen receptors (CARs) has produced clinical benefits for the treatment of hematologic diseases. To extend this approach to breast cancer, we generated CAR T cells directed against mucin1 (MUC1), an aberrantly glycosylated neoantigen that is overexpressed by malignant cells and whose expression has been correlated with poor prognosis. Furthermore, to protect our tumor-targeted cells from the elevated levels of immune-inhibitory cytokines present in the tumor milieu, we co-expressed an inverted cytokine receptor linking the IL4 receptor exodomain with the IL7 receptor endodomain (4/7ICR) in order to transform the suppressive IL4 signal into one that would enhance the anti-tumor effects of our CAR T cells at the tumor site. First (1G - CD3ζ) and second generation (2G - 41BB.CD3ζ) MUC1-specific CARs were constructed using the HMFG2 scFv. Following retroviral transduction transgenic expression of the CAR±ICR was assessed by flow cytometry. In vitro CAR/ICR T cell function was measured by assessing cell proliferation and short- and long-term cytotoxic activity using MUC1+ MDA MB 468 cells as targets. In vivo anti-tumor activity was assessed using IL4-producing MDA MB 468 tumor-bearing mice using calipers to assess tumor volume and bioluminescence imaging to track T cells. In the IL4-rich tumor milieu, 1G CAR.MUC1 T cells failed to expand or kill MUC1+ tumors and while co-expression of the 4/7ICR promoted T cell expansion, in the absence of co-stimulatory signals the outgrowing cells exhibited an exhausted phenotype characterized by PD-1 and TIM3 upregulation and failed to control tumor growth. However, by co-expressing 2G CAR.MUC1 (signal 1 - activation + signal 2 - co-stimulation) and 4/7ICR (signal 3 - cytokine), transgenic T cells selectively expanded at the tumor site and produced potent and durable tumor control in vitro and in vivo. Our findings demonstrate the feasibility of targeting breast

  17. Understanding the slow depletion of memory CD4+ T cells in HIV infection.

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    Andrew Yates

    2007-05-01

    Full Text Available The asymptomatic phase of HIV infection is characterised by a slow decline of peripheral blood CD4(+ T cells. Why this decline is slow is not understood. One potential explanation is that the low average rate of homeostatic proliferation or immune activation dictates the pace of a "runaway" decline of memory CD4(+ T cells, in which activation drives infection, higher viral loads, more recruitment of cells into an activated state, and further infection events. We explore this hypothesis using mathematical models.Using simple mathematical models of the dynamics of T cell homeostasis and proliferation, we find that this mechanism fails to explain the time scale of CD4(+ memory T cell loss. Instead it predicts the rapid attainment of a stable set point, so other mechanisms must be invoked to explain the slow decline in CD4(+ cells.A runaway cycle in which elevated CD4(+ T cell activation and proliferation drive HIV production and vice versa cannot explain the pace of depletion during chronic HIV infection. We summarize some alternative mechanisms by which the CD4(+ memory T cell homeostatic set point might slowly diminish. While none are mutually exclusive, the phenomenon of viral rebound, in which interruption of antiretroviral therapy causes a rapid return to pretreatment viral load and T cell counts, supports the model of virus adaptation as a major force driving depletion.

  18. Lck/PLCγ control migration and proliferation of interleukin (IL)-2-stimulated T cells via the Rac1 GTPase/glycogen phosphorylase pathway.

    Science.gov (United States)

    Llavero, Francisco; Artaso, Alain; Lacerda, Hadriano M; Parada, Luis A; Zugaza, José L

    2016-11-01

    Recently, we have reported that the IL-2-stimulated T cells activate PKCθ in order to phosphorylate the serine residues of αPIX-RhoGEF, and to switch on the Rac1/PYGM pathway resulting in T cell migration and proliferation. However, the molecular mechanism connecting the activated IL-2-R with the PKCθ/αPIX/Rac1/PYGM pathway is still unknown. In this study, the use of a combined pharmacological and genetic approach identified Lck, a Src family member, as the tyrosine kinase phosphorylating PLCγ leading to Rac1 and PYGM activation in the IL-2-stimulated Kit 225 T cells via the PKCθ/αPIX pathway. The PLCγ tyrosine phosphorylation was required to activate first PKCθ, and then αPIX and Rac1/PYGM. The results presented here delineate a novel signalling pathway ranking equally in importance to the three major pathways controlled by the IL-2-R, i.e. PI3K, Ras/MAPK and JAK/STAT pathways. The overall evidence strongly indicates that the central biological role of the novel IL-2-R/Lck/PLCγ/PKCθ/αPIX/Rac1/PYGM signalling pathway is directly related to the control of fundamental cellular processes such as T cell migration and proliferation. Copyright © 2016 The Authors. Published by Elsevier Inc. All rights reserved.

  19. Effect of melatonin on monochromatic light-induced T-lymphocyte proliferation in the thymus of chickens.

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    Chen, Fuju; Reheman, Aikebaier; Cao, Jing; Wang, Zixu; Dong, Yulan; Zhang, Yuxian; Chen, Yaoxing

    2016-08-01

    A total of 360 post-hatching day 0 (P0) Arbor Acre male broilers, including intact, sham operation and pinealectomy groups, were exposed to white light (WL), red light (RL), green light (GL) and blue light (BL) from a light-emitting diode (LED) system until for P14. We studied the effects of melatonin and its receptors on monochromatic light-induced T-lymphocyte proliferation in the thymus of broilers. The density of proliferating cell nuclear antigen (PCNA) cells and the proliferation of T-lymphocytes in response to Concanavalin A (ConA) in GL significantly increased both in vivo and in vitro (from 9.57% to 32.03% and from 34.30% to 50.53%, respectively) compared with other lights (p<0.005) and was strongly correlated with melatonin levels in plasma (p<0.005). Pinealectomy reduced the levels of circulatory melatonin and the proliferation of T-lymphocytes and eliminated the differences between GL and other lights (p<0.005). However, exogenous melatonin (10(-9)M) significantly increased the proliferative activity of T-lymphocyte by 9.64% (p=0.002). In addition, GL significantly increased mRNA expression levels of Mel1a, Mel1b and Mel1c receptors from 21.09% to 32.57%, and protein expression levels from 24.43% to 42.92% compared with RL (p<0.05). However, these effects were blocked after pinealectomy. Furthermore, 4P-PDOT (a selective Mel1b antagonist) and prazosin (a selective Mel1c antagonist) attenuated GL-induced T-lymphocyte proliferation in response to ConA (p=0.000). Luzindole (a nonselective Mel1a/Mel1b antagonist), however, did not induce these effects (p=0.334). These results suggest that melatonin may mediate GL-induced T-lymphocyte proliferation via the Mel1b and Mel1c receptors but not via the Mel1a receptor. Copyright © 2016 Elsevier B.V. All rights reserved.

  20. T-helper cell-mediated proliferation and cytokine responses against recombinant Merkel cell polyomavirus-like particles.

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    Arun Kumar

    Full Text Available The newly discovered Merkel Cell Polyomavirus (MCPyV resides in approximately 80% of Merkel cell carcinomas (MCC. Causal role of MCPyV for this rare and aggressive skin cancer is suggested by monoclonal integration and truncation of large T (LT viral antigen in MCC cells. The mutated MCPyV has recently been found in highly purified leukemic cells from patients with chronic lymphocytic leukemia (CLL, suggesting a pathogenic role also in CLL. About 50-80% of adults display MCPyV-specific antibodies. The humoral immunity does not protect against the development of MCC, as neutralizing MCPyV antibodies occur in higher levels among MCC patients than healthy controls. Impaired T-cell immunity has been linked with aggressive MCC behavior. Therefore, cellular immunity appears to be important in MCPyV infection surveillance. In order to elucidate the role of MCPyV-specific Th-cell immunity, peripheral blood mononuclear cells (PBMC of healthy adults were stimulated with MCPyV VP1 virus-like particles (VLPs, using human bocavirus (HBoV VLPs and Candida albicans antigen as positive controls. Proliferation, IFN-γ, IL-13 and IL-10 responses were examined in 15 MCPyV-seropositive and 15 seronegative volunteers. With the MCPyV antigen, significantly stronger Th-cell responses were found in MCPyV-seropositive than MCPyV-seronegative subjects, whereas with the control antigens, the responses were statistically similar. The most readily detectable cytokine was IFN-γ. The MCPyV antigen tended to induce stronger IFN-γ responses than HBoV VLP antigen. Taken together, MCPyV-specific Th-cells elicit vigorous IFN-γ responses. IFN-γ being a cytokine with major antiviral and tumor suppressing functions, Th-cells are suggested to be important mediators of MCPyV-specific immune surveillance.

  1. Cell-Intrinsic Roles for Autophagy in Modulating CD4 T Cell Functions

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    Elise Jacquin

    2018-05-01

    Full Text Available The catabolic process of autophagy plays important functions in inflammatory and immune responses by modulating innate immunity and adaptive immunity. Over the last decade, a cell-intrinsic role for autophagy in modulating CD4 T cell functions and differentiation was revealed. After the initial observation of autophagosomes in effector CD4 T cells, further work has shown that not only autophagy levels are modulated in CD4 T cells in response to environmental signals but also that autophagy critically affects the biology of these cells. Mouse models of autophagy deletion in CD4 T cells have indeed shown that autophagy is essential for CD4 T cell survival and homeostasis in peripheral lymphoid organs. Furthermore, autophagy is required for CD4 T cell proliferation and cytokine production in response to T cell receptor activation. Recent developments have uncovered that autophagy controls CD4 T cell differentiation and functions. While autophagy is required for the maintenance of immunosuppressive functions of regulatory T cells, it restrains the differentiation of TH9 effector cells, thus limiting their antitumor and pro-inflammatory properties. We will here discuss these findings that collectively suggest that therapeutic strategies targeting autophagy could be exploited for the treatment of cancer and inflammatory diseases.

  2. The ThPOK transcription factor differentially affects the development and function of self-specific CD8(+) T cells and regulatory CD4(+) T cells.

    Science.gov (United States)

    Twu, Yuh-Ching; Teh, Hung-Sia

    2014-03-01

    The zinc finger transcription factor ThPOK plays a crucial role in CD4 T-cell development and CD4/CD8 lineage decision. In ThPOK-deficient mice, developing T cells expressing MHC class II-restricted T-cell receptors are redirected into the CD8 T-cell lineage. In this study, we investigated whether the ThPOK transgene affected the development and function of two additional types of T cells, namely self-specific CD8 T cells and CD4(+) FoxP3(+) T regulatory cells. Self-specific CD8 T cells are characterized by high expression of CD44, CD122, Ly6C, 1B11 and proliferation in response to either IL-2 or IL-15. The ThPOK transgene converted these self-specific CD8 T cells into CD4 T cells. The converted CD4(+) T cells are no longer self-reactive, lose the characteristics of self-specific CD8 T cells, acquire the properties of conventional CD4 T cells and survive poorly in peripheral lymphoid organs. By contrast, the ThPOK transgene promoted the development of CD4(+) FoxP3(+) regulatory T cells resulting in an increased recovery of CD4(+) FoxP3(+) regulatory T cells that expressed higher transforming growth factor-β-dependent suppressor activity. These studies indicate that the ThPOK transcription factor differentially affects the development and function of self-specific CD8 T cells and CD4(+) FoxP3(+) regulatory T cells. © 2013 John Wiley & Sons Ltd.

  3. EBV-associated post-transplantation B-cell lymphoproliferative disorder following allogenic stem cell transplantation for acute lymphoblastic leukaemia: tumor regression after reduction of immunosuppression - a case report

    Directory of Open Access Journals (Sweden)

    Niedobitek Gerald

    2010-03-01

    Full Text Available Abstract Epstein-Barr virus (EBV-associated B-cell post-transplantation lymphoproliferative disorder (PTLD is a severe complication following stem cell transplantation. This is believed to occur as a result of iatrogenic immunosuppression leading to a relaxation of T-cell control of EBV infection and thus allowing viral reactivation and proliferation of EBV-infected B-lymphocytes. In support of this notion, reduction of immunosuppressive therapy may lead to regression of PTLD. We present a case of an 18-year-old male developing a monomorphic B-cell PTLD 2 months after receiving an allogenic stem cell transplant for acute lymphoblastic leukemia. Reduction of immunosuppressive therapy led to regression of lymphadenopathy. Nevertheless, the patient died 3 months afterwards due to extensive graft-vs.-host-disease and sepsis. As a diagnostic lymph node biopsy was performed only after reduction of immunosuppressive therapy, we are able to study the histopathological changes characterizing PTLD regression. We observed extensive apoptosis of blast cells, accompanied by an abundant infiltrate comprising predominantly CD8-positive, Granzyme B-positive T-cells. This observation supports the idea that regression of PTLD is mediated by cytotoxic T-cells and is in keeping with the observation that T-cell depletion, represents a major risk factor for the development of PTLD.

  4. Posttranscriptional Control of T Cell Effector Function by Aerobic Glycolysis

    NARCIS (Netherlands)

    Chang, Chih-Hao; Curtis, Jonathan D.; Maggi, Leonard B.; Faubert, Brandon; Villarino, Alejandro V.; O'Sullivan, David; Huang, Stanley Ching-Cheng; van der Windt, Gerritje J. W.; Blagih, Julianna; Qiu, Jing; Weber, Jason D.; Pearce, Edward J.; Jones, Russell G.; Pearce, Erika L.

    2013-01-01

    A "switch'' from oxidative phosphorylation (OXPHOS) to aerobic glycolysis is a hallmark of T cell activation and is thought to be required to meet the metabolic demands of proliferation. However, why proliferating cells adopt this less efficient metabolism, especially in an oxygen-replete

  5. Suppression of pro-inflammatory T-cell responses by human mesothelial cells.

    Science.gov (United States)

    Lin, Chan-Yu; Kift-Morgan, Ann; Moser, Bernhard; Topley, Nicholas; Eberl, Matthias

    2013-07-01

    Human γδ T cells reactive to the microbial metabolite (E)-4-hydroxy-3-methyl-but-2-enyl pyrophosphate (HMB-PP) contribute to acute inflammatory responses. We have previously shown that peritoneal dialysis (PD)-associated infections with HMB-PP producing bacteria are characterized by locally elevated γδ T-cell frequencies and poorer clinical outcome compared with HMB-PP negative infections, implying that γδ T cells may be of diagnostic, prognostic and therapeutic value in acute disease. The regulation by local tissue cells of these potentially detrimental γδ T-cell responses remains to be investigated. Freshly isolated γδ or αβ T cells were cultured with primary mesothelial cells derived from omental tissue, or with mesothelial cell-conditioned medium. Stimulation of cytokine production and proliferation by peripheral T cells in response to HMB-PP or CD3/CD28 beads was assessed by flow cytometry. Resting mesothelial cells were potent suppressors of pro-inflammatory γδ T cells as well as CD4+ and CD8+ αβ T cells. The suppression of γδ T-cell responses was mediated through soluble factors released by primary mesothelial cells and could be counteracted by SB-431542, a selective inhibitor of TGF-β and activin signalling. Recombinant TGF-β1 but not activin-A mimicked the mesothelial cell-mediated suppression of γδ T-cell responses to HMB-PP. The present findings indicate an important regulatory function of mesothelial cells in the peritoneal cavity by dampening pro-inflammatory T-cell responses, which may help preserve the tissue integrity of the peritoneal membrane in the steady state and possibly during the resolution of acute inflammation.

  6. Burn-injury affects gut-associated lymphoid tissues derived CD4+ T cells.

    Science.gov (United States)

    Fazal, Nadeem; Shelip, Alla; Alzahrani, Alhusain J

    2013-01-01

    After scald burn-injury, the intestinal immune system responds to maintain immune balance. In this regard CD4+T cells in Gut-Associated Lymphoid Tissues (GALT), like mesenteric lymph nodes (MLN) and Peyer's patches (PP) respond to avoid immune suppression following major injury such as burn. Therefore, we hypothesized that the gut CD4+T cells become dysfunctional and turn the immune homeostasis towards depression of CD4+ T cell-mediated adaptive immune responses. In the current study we show down regulation of mucosal CD4+ T cell proliferation, IL-2 production and cell surface marker expression of mucosal CD4+ T cells moving towards suppressive-type. Acute burn-injury lead to up-regulation of regulatory marker (CD25+), down regulation of adhesion (CD62L, CD11a) and homing receptor (CD49d) expression, and up-regulation of negative co-stimulatory (CTLA-4) molecule. Moreover, CD4+CD25+ T cells of intestinal origin showed resistance to spontaneous as well as induced apoptosis that may contribute to suppression of effector CD4+ T cells. Furthermore, gut CD4+CD25+ T cells obtained from burn-injured animals were able to down-regulate naïve CD4+ T cell proliferation following adoptive transfer of burn-injured CD4+CD25+ T cells into sham control animals, without any significant effect on cell surface activation markers. Together, these data demonstrate that the intestinal CD4+ T cells evolve a strategy to promote suppressive CD4+ T cell effector responses, as evidenced by enhanced CD4+CD25+ T cells, up-regulated CTLA-4 expression, reduced IL-2 production, tendency towards diminished apoptosis of suppressive CD4+ T cells, and thus lose their natural ability to regulate immune homeostasis following acute burn-injury and prevent immune paralysis.

  7. The Notch/Hes1 pathway sustains NF-κB activation through CYLD repression in T cell leukemia.

    Science.gov (United States)

    Espinosa, Lluis; Cathelin, Severine; D'Altri, Teresa; Trimarchi, Thomas; Statnikov, Alexander; Guiu, Jordi; Rodilla, Veronica; Inglés-Esteve, Julia; Nomdedeu, Josep; Bellosillo, Beatriz; Besses, Carles; Abdel-Wahab, Omar; Kucine, Nicole; Sun, Shao-Cong; Song, Guangchan; Mullighan, Charles C; Levine, Ross L; Rajewsky, Klaus; Aifantis, Iannis; Bigas, Anna

    2010-09-14

    It was previously shown that the NF-κB pathway is downstream of oncogenic Notch1 in T cell acute lymphoblastic leukemia (T-ALL). Here, we visualize Notch-induced NF-κB activation using both human T-ALL cell lines and animal models. We demonstrate that Hes1, a canonical Notch target and transcriptional repressor, is responsible for sustaining IKK activation in T-ALL. Hes1 exerts its effects by repressing the deubiquitinase CYLD, a negative IKK complex regulator. CYLD expression was found to be significantly suppressed in primary T-ALL. Finally, we demonstrate that IKK inhibition is a promising option for the targeted therapy of T-ALL as specific suppression of IKK expression and function affected both the survival of human T-ALL cells and the maintenance of the disease in vivo. Copyright © 2010 Elsevier Inc. All rights reserved.

  8. Alteration of the gene expression profile of T-cell receptor αβ-modified T-cells with diffuse large B-cell lymphoma specificity.

    Science.gov (United States)

    Zha, Xianfeng; Yin, Qingsong; Tan, Huo; Wang, Chunyan; Chen, Shaohua; Yang, Lijian; Li, Bo; Wu, Xiuli; Li, Yangqiu

    2013-05-01

    Antigen-specific, T-cell receptor (TCR)-modified cytotoxic T lymphocytes (CTLs) that target tumors are an attractive strategy for specific adoptive immunotherapy. Little is known about whether there are any alterations in the gene expression profile after TCR gene transduction in T cells. We constructed TCR gene-redirected CTLs with specificity for diffuse large B-cell lymphoma (DLBCL)-associated antigens to elucidate the gene expression profiles of TCR gene-redirected T-cells, and we further analyzed the gene expression profile pattern of these redirected T-cells by Affymetrix microarrays. The resulting data were analyzed using Bioconductor software, a two-fold cut-off expression change was applied together with anti-correlation of the profile ratios to render the microarray analysis set. The fold change of all genes was calculated by comparing the three TCR gene-modified T-cells and a negative control counterpart. The gene pathways were analyzed using Bioconductor and Kyoto Encyclopedia of Genes and Genomes. Identical genes whose fold change was greater than or equal to 2.0 in all three TCR gene-redirected T-cell groups in comparison with the negative control were identified as the differentially expressed genes. The differentially expressed genes were comprised of 33 up-regulated genes and 1 down-regulated gene including JUNB, FOS, TNF, INF-γ, DUSP2, IL-1B, CXCL1, CXCL2, CXCL9, CCL2, CCL4, and CCL8. These genes are mainly involved in the TCR signaling, mitogen-activated protein kinase signaling, and cytokine-cytokine receptor interaction pathways. In conclusion, we characterized the gene expression profile of DLBCL-specific TCR gene-redirected T-cells. The changes corresponded to an up-regulation in the differentiation and proliferation of the T-cells. These data may help to explain some of the characteristics of the redirected T-cells.

  9. Comprehensive Approach for Identifying the T Cell Subset Origin of CD3 and CD28 Antibody-Activated Chimeric Antigen Receptor-Modified T Cells.

    Science.gov (United States)

    Schmueck-Henneresse, Michael; Omer, Bilal; Shum, Thomas; Tashiro, Haruko; Mamonkin, Maksim; Lapteva, Natalia; Sharma, Sandhya; Rollins, Lisa; Dotti, Gianpietro; Reinke, Petra; Volk, Hans-Dieter; Rooney, Cliona M

    2017-07-01

    The outcome of therapy with chimeric Ag receptor (CAR)-modified T cells is strongly influenced by the subset origin of the infused T cells. However, because polyclonally activated T cells acquire a largely CD45RO + CCR7 - effector memory phenotype after expansion, regardless of subset origin, it is impossible to know which subsets contribute to the final T cell product. To determine the contribution of naive T cell, memory stem T cell, central memory T cell, effector memory T cell, and terminally differentiated effector T cell populations to the CD3 and CD28-activated CAR-modified T cells that we use for therapy, we followed the fate and function of individually sorted CAR-modified T cell subsets after activation with CD3 and CD28 Abs (CD3/28), transduction and culture alone, or after reconstitution into the relevant subset-depleted population. We show that all subsets are sensitive to CAR transduction, and each developed a distinct T cell functional profile during culture. Naive-derived T cells showed the greatest rate of proliferation but had more limited effector functions and reduced killing compared with memory-derived populations. When cultured in the presence of memory T cells, naive-derived T cells show increased differentiation, reduced effector cytokine production, and a reduced reproliferative response to CAR stimulation. CD3/28-activated T cells expanded in IL-7 and IL-15 produced greater expansion of memory stem T cells and central memory T cell-derived T cells compared with IL-2. Our strategy provides a powerful tool to elucidate the characteristics of CAR-modified T cells, regardless of the protocol used for expansion, reveals the functional properties of each expanded T cell subset, and paves the way for a more detailed evaluation of the effects of manufacturing changes on the subset contribution to in vitro-expanded T cells. Copyright © 2017 by The American Association of Immunologists, Inc.

  10. Colorectal cancer cells suppress CD4+ T cells immunity through canonical Wnt signaling.

    Science.gov (United States)

    Sun, Xuan; Liu, Suoning; Wang, Daguang; Zhang, Yang; Li, Wei; Guo, Yuchen; Zhang, Hua; Suo, Jian

    2017-02-28

    Understanding how colorectal cancer escapes from immunosurveillance and immune attack is important for developing novel immunotherapies for colorectal cancer. In this study we evaluated the role of canonical Wnt signaling in the regulation of T cell function in a mouse colorectal cancer model. We found that colorectal cancer cells expressed abundant Wnt ligands, and intratumoral T cells expressed various Frizzled proteins. Meanwhile, both active β-catenin and total β-catenin were elevated in intratumoral T cells. In vitro study indicated that colorectal cancer cells suppressed IFN-γ expression and increased IL-17a expression in activated CD4+ T cells. However, the cytotoxic activity of CD8+ T cells was not altered by colorectal cancer cells. To further evaluate the importance of Wnt signaling for CD4+ T cell-mediated cancer immunity, β-catenin expression was enforced in CD4+ T cells using lentiviral transduction. In an adoptive transfer model, enforced expression of β-catenin in intratumoral CD4+ T cells increased IL-17a expression, enhanced proliferation and inhibited apoptosis of colorectal cancer cells. Taken together, our study disclosed a new mechanism by which colorectal cancer impairs T cell immunity.

  11. Changing T cell specificity by retroviral T cell receptor display

    NARCIS (Netherlands)

    Kessels, H. W.; van den Boom, M. D.; Spits, H.; Hooijberg, E.; Schumacher, T. N.

    2000-01-01

    The diversity of the T cell receptor (TCR) repertoire is limited, because of the processes of positive and negative T cell selection. To obtain T cells with specificities beyond the immune system's capacity, we have developed a strategy for retroviral TCR display. In this approach, a library of T

  12. CD19 CAR-T cells of defined CD4+:CD8+ composition in adult B cell ALL patients.

    Science.gov (United States)

    Turtle, Cameron J; Hanafi, Laïla-Aïcha; Berger, Carolina; Gooley, Theodore A; Cherian, Sindhu; Hudecek, Michael; Sommermeyer, Daniel; Melville, Katherine; Pender, Barbara; Budiarto, Tanya M; Robinson, Emily; Steevens, Natalia N; Chaney, Colette; Soma, Lorinda; Chen, Xueyan; Yeung, Cecilia; Wood, Brent; Li, Daniel; Cao, Jianhong; Heimfeld, Shelly; Jensen, Michael C; Riddell, Stanley R; Maloney, David G

    2016-06-01

    T cells that have been modified to express a CD19-specific chimeric antigen receptor (CAR) have antitumor activity in B cell malignancies; however, identification of the factors that determine toxicity and efficacy of these T cells has been challenging in prior studies in which phenotypically heterogeneous CAR-T cell products were prepared from unselected T cells. We conducted a clinical trial to evaluate CD19 CAR-T cells that were manufactured from defined CD4+ and CD8+ T cell subsets and administered in a defined CD4+:CD8+ composition to adults with B cell acute lymphoblastic leukemia after lymphodepletion chemotherapy. The defined composition product was remarkably potent, as 27 of 29 patients (93%) achieved BM remission, as determined by flow cytometry. We established that high CAR-T cell doses and tumor burden increase the risks of severe cytokine release syndrome and neurotoxicity. Moreover, we identified serum biomarkers that allow testing of early intervention strategies in patients at the highest risk of toxicity. Risk-stratified CAR-T cell dosing based on BM disease burden decreased toxicity. CD8+ T cell-mediated anti-CAR transgene product immune responses developed after CAR-T cell infusion in some patients, limited CAR-T cell persistence, and increased relapse risk. Addition of fludarabine to the lymphodepletion regimen improved CAR-T cell persistence and disease-free survival. Immunotherapy with a CAR-T cell product of defined composition enabled identification of factors that correlated with CAR-T cell expansion, persistence, and toxicity and facilitated design of lymphodepletion and CAR-T cell dosing strategies that mitigated toxicity and improved disease-free survival. ClinicalTrials.gov NCT01865617. R01-CA136551; Life Science Development Fund; Juno Therapeutics; Bezos Family Foundation.

  13. Mer tyrosine kinase promotes the survival of t(1;19)-positive acute lymphoblastic leukemia (ALL) in the central nervous system (CNS).

    Science.gov (United States)

    Krause, Sarah; Pfeiffer, Christian; Strube, Susanne; Alsadeq, Ameera; Fedders, Henning; Vokuhl, Christian; Loges, Sonja; Waizenegger, Jonas; Ben-Batalla, Isabel; Cario, Gunnar; Möricke, Anja; Stanulla, Martin; Schrappe, Martin; Schewe, Denis M

    2015-01-29

    Patients with t(1;19)-positive acute lymphoblastic leukemia (ALL) are prone to central nervous system (CNS) relapses, and expression of the TAM (Tyro3, Axl, and Mer) receptor Mer is upregulated in these leukemias. We examined the functional role of Mer in the CNS in preclinical models and performed correlative studies in 64 t(1;19)-positive and 93 control pediatric ALL patients. ALL cells were analyzed in coculture with human glioma cells and normal rat astrocytes: CNS coculture caused quiescence and protection from methotrexate toxicity in Mer(high) ALL cell lines, which was antagonized by short hairpin RNA-mediated knockdown of Mer. Mer expression was upregulated, prosurvival Akt and mitogen-activated protein kinase signaling were activated, and secretion of the Mer ligand Galectin-3 was stimulated. Mer(high) t(1;19) primary cells caused CNS involvement to a larger extent in murine xenografts than in their Mer(low) counterparts. Leukemic cells from Mer(high) xenografts showed enhanced survival in coculture. Treatment of Mer(high) patient cells with the Mer-specific inhibitor UNC-569 in vivo delayed leukemia onset, reduced CNS infiltration, and prolonged survival of mice. Finally, a correlation between high Mer expression and CNS positivity upon initial diagnosis was observed in t(1;19) patients. Our data provide evidence that Mer is associated with survival in the CNS in t(1;19)-positive ALL, suggesting a role as a diagnostic marker and therapeutic target. © 2015 by The American Society of Hematology.

  14. Regulatory Eosinophils Suppress T Cells Partly through Galectin-10.

    Science.gov (United States)

    Lingblom, Christine; Andersson, Jennie; Andersson, Kerstin; Wennerås, Christine

    2017-06-15

    Eosinophils have the capacity to regulate the function of T cell subsets. Our aim was to test the hypothesis of the existence of a regulatory subset of eosinophils. Human eosinophils were incubated with T cells that were stimulated with allogeneic leukocytes or CD3/CD28 cross-linking. After 2 d of coculture, 11% of the eosinophils gained CD16 expression. A CD16 hi subset of eosinophils, encompassing 1-5% of all eosinophils, was also identified in the blood of healthy subjects. FACS sorting showed that these CD16 hi eosinophils were significantly stronger suppressors of T cell proliferation than were conventional CD16 neg eosinophils. Human eosinophils contain stores of the immunoregulatory protein galectin-10. We found that Ab-mediated neutralization of galectin-10 partially abrogated the suppressive function of the eosinophils. Moreover, recombinant galectin-10 by itself was able to suppress T cell proliferation. Finally, we detected galectin-10-containing immune synapses between eosinophils and lymphocytes. To conclude, we describe a subset of suppressive eosinophils expressing CD16 that may escape detection because CD16-based negative selection is the standard procedure for the isolation of human eosinophils. Moreover, we show that galectin-10 functions as a T cell-suppressive molecule in eosinophils. Copyright © 2017 by The American Association of Immunologists, Inc.

  15. CD19 CAR–T cells of defined CD4+:CD8+ composition in adult B cell ALL patients

    Science.gov (United States)

    Turtle, Cameron J.; Hanafi, Laïla-Aïcha; Berger, Carolina; Gooley, Theodore A.; Cherian, Sindhu; Hudecek, Michael; Sommermeyer, Daniel; Melville, Katherine; Pender, Barbara; Budiarto, Tanya M.; Robinson, Emily; Steevens, Natalia N.; Chaney, Colette; Soma, Lorinda; Chen, Xueyan; Li, Daniel; Cao, Jianhong; Heimfeld, Shelly; Jensen, Michael C.; Riddell, Stanley R.; Maloney, David G.

    2016-01-01

    BACKGROUND. T cells that have been modified to express a CD19-specific chimeric antigen receptor (CAR) have antitumor activity in B cell malignancies; however, identification of the factors that determine toxicity and efficacy of these T cells has been challenging in prior studies in which phenotypically heterogeneous CAR–T cell products were prepared from unselected T cells. METHODS. We conducted a clinical trial to evaluate CD19 CAR–T cells that were manufactured from defined CD4+ and CD8+ T cell subsets and administered in a defined CD4+:CD8+ composition to adults with B cell acute lymphoblastic leukemia after lymphodepletion chemotherapy. RESULTS. The defined composition product was remarkably potent, as 27 of 29 patients (93%) achieved BM remission, as determined by flow cytometry. We established that high CAR–T cell doses and tumor burden increase the risks of severe cytokine release syndrome and neurotoxicity. Moreover, we identified serum biomarkers that allow testing of early intervention strategies in patients at the highest risk of toxicity. Risk-stratified CAR–T cell dosing based on BM disease burden decreased toxicity. CD8+ T cell–mediated anti-CAR transgene product immune responses developed after CAR–T cell infusion in some patients, limited CAR–T cell persistence, and increased relapse risk. Addition of fludarabine to the lymphodepletion regimen improved CAR–T cell persistence and disease-free survival. CONCLUSION. Immunotherapy with a CAR–T cell product of defined composition enabled identification of factors that correlated with CAR–T cell expansion, persistence, and toxicity and facilitated design of lymphodepletion and CAR–T cell dosing strategies that mitigated toxicity and improved disease-free survival. TRIAL REGISTRATION. ClinicalTrials.gov NCT01865617. FUNDING. R01-CA136551; Life Science Development Fund; Juno Therapeutics; Bezos Family Foundation. PMID:27111235

  16. Helios expression in regulatory T cells promotes immunosuppression, angiogenesis and the growth of leukemia cells in pediatric acute lymphoblastic leukemia.

    Science.gov (United States)

    Li, Xue; Li, Dong; Huang, Xiaoyang; Zhou, Panpan; Shi, Qing; Zhang, Bing; Ju, Xiuli

    2018-04-01

    Regulatory T cells (Tregs) characterized by the transcription factor forkhead box P3 (FoxP3) are crucial for maintaining immune tolerance and preventing autoimmunity. However, FoxP3 does not function alone and Helios is considered a potential candidate for defining Treg subsets. In this study, we investigated the expression and function of Helios for identifying Tregs in childhood precursor B-cell acute lymphoblastic leukemia (pre-B ALL). Our results demonstrated that patients with pre-B ALL had a higher percentage of Helios + FoxP3 + CD4 + Tregs. And there was a positive correlation between the expression of Helios and the suppressive function of Tregs, the risk gradation of ALL. Helios in combination with CD4 and FoxP3 may be an effective way to detect functional Tregs in pre-B ALL by promoting the secretion of transforming growth factor (TGF)-β1. Furthermore, Helios + Tregs could regulate angiogenesis in the BM niche of pre-B ALL via the VEGFA/VEGFR2 pathway. We also found Helios + Tregs decreased apoptosis rate of nalm-6 cells by up-regulating the expression of anti-apoptosis protein Bcl-2. In summary, these data strongly imply the physiological importance of Helios expression in Tregs, and suggest that the manipulation of Helios may serve as a novel strategy for cancer immunotherapy. Copyright © 2018 Elsevier Ltd. All rights reserved.

  17. Roles of calpain-calpastatin system (CCS) in human T cell activation.

    Science.gov (United States)

    Mikosik, Anna; Jasiulewicz, Aleksandra; Daca, Agnieszka; Henc, Izabella; Frąckowiak, Joanna E; Ruckemann-Dziurdzińska, Katarzyna; Foerster, Jerzy; Le Page, Aurelie; Bryl, Ewa; Fulop, Tamas; Witkowski, Jacek M

    2016-11-22

    The immune response is determined by the speed of the T cell reaction to antigens assured by a state of readiness for proliferation and cytokine secretion. Proliferation, apoptosis and motion of many cell types are controlled by cytoplasmic proteases - µ- and m-calpain - and their inhibitor calpastatin, together forming the "calpain-calpastatin system" (CCS), assumed to modify their targets only upon activation-dependent cytoplasmic Ca2+ increase. Contrastingly to this notion, using quantitative real time PCR and semiquantitative flow cytometry respectively, we show here that the CCS genes are constitutively expressed, and that both calpains are constitutively active in resting, circulating human CD4+ and CD8+ lymphocytes. Furthermore, we demonstrate that calpain inhibition in the resting T cells prevents them from proliferation in vitro and greatly reduces secretion of multiple cytokines. The mechanistic reason for these effects of calpain inhibition on T cell functions might be the demonstrated significant reduction of the expression of active (phosphorylated) upstream signalling molecules, including the phospholipase C gamma, p56Lck and NFκB, in the inhibitor-treated cells. Thus, we propose that the constitutive, self-regulatory calpain-calpastatin system activity in resting human T cells is a necessary, controlling element of their readiness for complex and effective response to antigenic challenge.

  18. Regulation of CD95 expression and CD95-mediated cell death by interferon-gamma in acute lymphoblastic leukemia with chromosomal translocation t(4;11).

    Science.gov (United States)

    Dörrie, J; Schuh, W; Keil, A; Bongards, E; Greil, J; Fey, G H; Zunino, S J

    1999-10-01

    The regulatory effects of IFNgamma on CD95 expression and CD95-mediated cell death were investigated in three high-risk pro-B acute lymphoblastic leukemia (ALL) lines that carry the chromosomal translocation t(4;11)(q21;q23). These leukemias are characteristically refractory to conventional chemotherapeutic treatments operating through the induction of apoptosis. However, the mechanisms leading to increased cell survival and resistance to cell death in these leukemias are largely unknown. Interferon-gamma (IFNgamma), a potent inhibitor of hematopoiesis, acts in part by upregulating CD95 and sensitizing cells to CD95-induced apoptosis. The t(4;11) lines SEM, RS4;11, and MV4;11 expressed low levels of CD95, but were completely resistant to CD95-mediated death. Addition of IFNgamma markedly upregulated CD95 expression in SEM (8-9-fold), RS4;11 (2-3-fold), and MV4;11 (2-3-fold) lines. However, after treatment with IFNgamma, only an 11% increase in sensitivity to CD95-mediated cell death was observed in SEM cells, whereas RS4;11 and MV4;11 cells remained resistant. Cycloheximide, but not actinomycin D or brefeldin A, increased CD95-specific cell death only in IFNgamma-treated RS4;11 cells by approximately 12%. Abundant levels of Bcl-2 and Bcl-XL, known to inhibit CD95-signaling in some cells, were present suggesting a possible role for both molecules in the resistance to CD95-mediated cell death. Resistance of the leukemic blasts to CD95-mediated cell death and the failure of IFNgamma to substantially sensitize the CD95-signaling pathway may contribute to the highly malignant phenotype of pro-B ALL with translocation t(4;11).

  19. T-cell acute leukaemia exhibits dynamic interactions with bone marrow microenvironments.

    Science.gov (United States)

    Hawkins, Edwin D; Duarte, Delfim; Akinduro, Olufolake; Khorshed, Reema A; Passaro, Diana; Nowicka, Malgorzata; Straszkowski, Lenny; Scott, Mark K; Rothery, Steve; Ruivo, Nicola; Foster, Katie; Waibel, Michaela; Johnstone, Ricky W; Harrison, Simon J; Westerman, David A; Quach, Hang; Gribben, John; Robinson, Mark D; Purton, Louise E; Bonnet, Dominique; Lo Celso, Cristina

    2016-10-27

    It is widely accepted that complex interactions between cancer cells and their surrounding microenvironment contribute to disease development, chemo-resistance and disease relapse. In light of this observed interdependency, novel therapeutic interventions that target specific cancer stroma cell lineages and their interactions are being sought. Here we studied a mouse model of human T-cell acute lymphoblastic leukaemia (T-ALL) and used intravital microscopy to monitor the progression of disease within the bone marrow at both the tissue-wide and single-cell level over time, from bone marrow seeding to development/selection of chemo-resistance. We observed highly dynamic cellular interactions and promiscuous distribution of leukaemia cells that migrated across the bone marrow, without showing any preferential association with bone marrow sub-compartments. Unexpectedly, this behaviour was maintained throughout disease development, from the earliest bone marrow seeding to response and resistance to chemotherapy. Our results reveal that T-ALL cells do not depend on specific bone marrow microenvironments for propagation of disease, nor for the selection of chemo-resistant clones, suggesting that a stochastic mechanism underlies these processes. Yet, although T-ALL infiltration and progression are independent of the stroma, accumulated disease burden leads to rapid, selective remodelling of the endosteal space, resulting in a complete loss of mature osteoblastic cells while perivascular cells are maintained. This outcome leads to a shift in the balance of endogenous bone marrow stroma, towards a composition associated with less efficient haematopoietic stem cell function. This novel, dynamic analysis of T-ALL interactions with the bone marrow microenvironment in vivo, supported by evidence from human T-ALL samples, highlights that future therapeutic interventions should target the migration and promiscuous interactions of cancer cells with the surrounding microenvironment

  20. TRAF2 regulates peripheral CD8(+) T-cell and NKT-cell homeostasis by modulating sensitivity to IL-15.

    Science.gov (United States)

    Villanueva, Jeanette E; Malle, Elisabeth K; Gardam, Sandra; Silveira, Pablo A; Zammit, Nathan W; Walters, Stacey N; Brink, Robert; Grey, Shane T

    2015-06-01

    In this study, a critical and novel role for TNF receptor (TNFR) associated factor 2 (TRAF2) is elucidated for peripheral CD8(+) T-cell and NKT-cell homeostasis. Mice deficient in TRAF2 only in their T cells (TRAF2TKO) show ∼40% reduction in effector memory and ∼50% reduction in naïve CD8(+) T-cell subsets. IL-15-dependent populations were reduced further, as TRAF2TKO mice displayed a marked ∼70% reduction in central memory CD8(+) CD44(hi) CD122(+) T cells and ∼80% decrease in NKT cells. TRAF2TKO CD8(+) CD44(hi) T cells exhibited impaired dose-dependent proliferation to exogenous IL-15. In contrast, TRAF2TKO CD8(+) T cells proliferated normally to anti-CD3 and TRAF2TKO CD8(+) CD44(hi) T cells exhibited normal proliferation to exogenous IL-2. TRAF2TKO CD8(+) T cells expressed normal levels of IL-15-associated receptors and possessed functional IL-15-mediated STAT5 phosphorylation, however TRAF2 deletion caused increased AKT activation. Loss of CD8(+) CD44(hi) CD122(+) and NKT cells was mechanistically linked to an inability to respond to IL-15. The reduced CD8(+) CD44(hi) CD122(+) T-cell and NKT-cell populations in TRAF2TKO mice were rescued in the presence of high dose IL-15 by IL-15/IL-15Rα complex administration. These studies demonstrate a critical role for TRAF2 in the maintenance of peripheral CD8(+) CD44(hi) CD122(+) T-cell and NKT-cell homeostasis by modulating sensitivity to T-cell intrinsic growth factors such as IL-15. © 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  1. Human T cell leukemia virus type I prevents cell surface expression of the T cell receptor through down-regulation of the CD3-gamma, -delta, -epsilon, and -zeta genes

    NARCIS (Netherlands)

    de Waal Malefyt, R.; Yssel, H.; Spits, H.; de Vries, J. E.; Sancho, J.; Terhorst, C.; Alarcon, B.

    1990-01-01

    Infection and transformation by human T cell leukemia virus type I (HTLV-I) up-regulates expression of several inducible genes including those coding for cytokines involved in the proliferation of normal and leukemic T cells. We demonstrate that HTLV-I can also shut off expression of the CD3-gamma,

  2. Saccharomyces boulardii inhibits lipopolysaccharide-induced activation of human dendritic cells and T cell proliferation

    Science.gov (United States)

    Thomas, S; Przesdzing, I; Metzke, D; Schmitz, J; Radbruch, A; Baumgart, D C

    2009-01-01

    Saccharomyces boulardii (Sb) is a probiotic yeast preparation that has demonstrated efficacy in inflammatory and infectious disorders of the gastrointestinal tract in controlled clinical trials. Although patients clearly benefit from treatment with Sb, little is known on how Sb unfolds its anti-inflammatory properties in humans. Dendritic cells (DC) balance tolerance and immunity and are involved critically in the control of T cell activation. Thus, they are believed to have a pivotal role in the initiation and perpetuation of chronic inflammatory disorders, not only in the gut. We therefore decided to investigate if Sb modulates DC function. Culture of primary (native, non-monocyte-derived) human myeloid CD1c+CD11c+CD123– DC (mDC) in the presence of Sb culture supernatant (active component molecular weight < 3 kDa, as evaluated by membrane partition chromatography) reduced significantly expression of the co-stimulatory molecules CD40 and CD80 (P < 0·01) and the DC mobilization marker CC-chemokine receptor CCR7 (CD197) (P < 0·001) induced by the prototypical microbial antigen lipopolysaccharide (LPS). Moreover, secretion of key proinflammatory cytokines such as tumour necrosis factor-α and interleukin (IL)-6 were notably reduced, while the secretion of anti-inflammatory IL-10 increased. Finally, Sb supernatant inhibited the proliferation of naive T cells in a mixed lymphocyte reaction with mDC. In summary, our data suggest that Sb may exhibit part of its anti-inflammatory potential through modulation of DC phenotype, function and migration by inhibition of their immune response to bacterial microbial surrogate antigens such as LPS. PMID:19161443

  3. T-Cell Subsets Predict Mortality in Malnourished Zambian Adults Initiating Antiretroviral Therapy.

    Directory of Open Access Journals (Sweden)

    Caroline C Chisenga

    Full Text Available To estimate the prognostic value of T-cell subsets in Zambian patients initiating antiretroviral therapy (ART, and to assess the impact of a nutritional intervention on T-cell subsets.This was a sub-study of a randomised clinical trial of a nutritional intervention for malnourished adults initiating ART. Participants in a randomised controlled trial (NUSTART trial were enrolled between April and December 2012. Participants received lipid-based nutritional supplement either with or without additional vitamins and minerals. Immunophenotyping was undertaken at baseline and, in survivors, after 12 weeks of ART to characterize T-cell subsets using the markers CD3, CD4, CD8, CD45RA, CCR7, CD28, CD57, CD31, α4β7, Ki67, CD25 and HLA-DR. Univariate and multivariate survival analysis was performed, and responses to treatment were analysed using the Wicoxon rank-sum test.Among 181 adults, 36 (20% died by 12 weeks after starting ART. In univariate analysis, patients who died had fewer proliferating, more naïve and fewer gut homing CD4+ T-cells compared to survivors; and more senescent and fewer proliferating CD8+ T-cells. In a multivariate Cox regression model high naïve CD4+, low proliferating CD4+, high senescent CD8+ and low proliferating CD8+ subsets were independently associated with increased risk of death. Recent CD4+ thymic emigrants increased less between recruitment and 12 weeks of ART in the intervention group compared to the control group.Specific CD4+ T-cell subsets are of considerable prognostic significance for patients initiating ART in Zambia, but only thymic output responded to this nutritional intervention.

  4. Activated human T cells secrete exosomes that participate in IL-2 mediated immune response signaling.

    Directory of Open Access Journals (Sweden)

    Jessica Wahlgren

    Full Text Available It has previously been shown that nano-meter sized vesicles (30-100 nm, exosomes, secreted by antigen presenting cells can induce T cell responses thus showing the potential of exosomes to be used as immunological tools. Additionally, activated CD3⁺ T cells can secrete exosomes that have the ability to modulate different immunological responses. Here, we investigated what effects exosomes originating from activated CD3⁺ T cells have on resting CD3⁺ T cells by studying T cell proliferation, cytokine production and by performing T cell and exosome phenotype characterization. Human exosomes were generated in vitro following CD3⁺ T cell stimulation with anti-CD28, anti-CD3 and IL-2. Our results show that exosomes purified from stimulated CD3⁺ T cells together with IL-2 were able to generate proliferation in autologous resting CD3⁺ T cells. The CD3⁺ T cells stimulated with exosomes together with IL-2 had a higher proportion of CD8⁺ T cells and had a different cytokine profile compared to controls. These results indicate that activated CD3⁺ T cells communicate with resting autologous T cells via exosomes.

  5. Clonal analysis of T-cell responses to herpes simplex virus: isolation, characterization and antiviral properties of an antigen-specific helper T-cell clone.

    Science.gov (United States)

    Leung, K N; Nash, A A; Sia, D Y; Wildy, P

    1984-12-01

    A herpes simplex virus (HSV)-specific long-term T-cell clone has been established from the draining lymph node cells of BALB/c mice; the cells required repeated in vitro restimulation with UV-irradiated virus. The established T-cell clone expresses the Thy-1 and Lyt-1+2,3- surface antigens. For optimal proliferation of the cloned cells, both the presence of specific antigen and an exogenous source of T-cell growth factor are required. The proliferative response of the cloned T cells was found to be virus-specific but it did not distinguish between HSV-1 and HSV-2. Adoptive cell transfer of the cloned T cells helped primed B cells to produce anti-herpes antibodies: the response was antigen-specific and cell dose-dependent. The clone failed to produce a significant DTH reaction in vivo, but did produce high levels of macrophage-activating factor. Furthermore, the T-cell clone could protect from HSV infection, as measured by a reduction in local virus growth, and by enhanced survival following the challenge of mice with a lethal dose of virus. The mechanism(s) whereby this clone protects in vivo is discussed.

  6. T-cell activation and early gene response in dogs.

    Directory of Open Access Journals (Sweden)

    Sally-Anne Mortlock

    Full Text Available T-cells play a crucial role in canine immunoregulation and defence against invading pathogens. Proliferation is fundamental to T-cell differentiation, homeostasis and immune response. Initiation of proliferation following receptor mediated stimuli requires a temporally programmed gene response that can be identified as immediate-early, mid- and late phases. The immediate-early response genes in T-cell activation engage the cell cycle machinery and promote subsequent gene activation events. Genes involved in this immediate-early response in dogs are yet to be identified. The present study was undertaken to characterise the early T-cell gene response in dogs to improve understanding of the genetic mechanisms regulating immune function. Gene expression profiles were characterised using canine gene expression microarrays and quantitative reverse transcription PCR (qRT-PCR, and paired samples from eleven dogs. Significant functional annotation clusters were identified following stimulation with phytohemagluttinin (PHA (5μg/ml, including the Toll-like receptor signaling pathway and phosphorylation pathways. Using strict statistical criteria, 13 individual genes were found to be differentially expressed, nine of which have ontologies that relate to proliferation and cell cycle control. These included, prostaglandin-endoperoxide synthase 2 (PTGS2/COX2, early growth response 1 (EGR1, growth arrest and DNA damage-inducible gene (GADD45B, phorbol-12-myristate-13-acetate-induced protein 1 (PMAIP1, V-FOS FBJ murine osteosarcoma viral oncogene homolog (FOS, early growth response 2 (EGR2, hemogen (HEMGN, polo-like kinase 2 (PLK2 and polo-like kinase 3 (PLK3. Differential gene expression was re-examined using qRT-PCR, which confirmed that EGR1, EGR2, PMAIP1, PTGS2, FOS and GADD45B were significantly upregulated in stimulated cells and ALAS2 downregulated. PTGS2 and EGR1 showed the highest levels of response in these dogs. Both of these genes are involved in

  7. Circulating rotavirus-specific T cells have a poor functional profile

    International Nuclear Information System (INIS)

    Parra, Miguel; Herrera, Daniel; Jácome, María Fernanda; Mesa, Martha C.; Rodríguez, Luz-Stella; Guzmán, Carolina; Angel, Juana; Franco, Manuel A.

    2014-01-01

    Frequencies of circulating T cells producing IFN-γ, TNF-α, and IL-2, and percentages of T cells proliferating after stimulation with rotavirus (RV), tetanus toxoid, and influenza were evaluated in PBMC derived from healthy adults and children. In addition, the potential anergic state of RV-specific T cells was analyzed by stimulation of PBMC with RV antigen in the presence of three anergy inhibitors (rIL-2, rIL-12, or DGKα-i). The quality and magnitude of RV-T cell responses were significantly lower than those of tetanus toxoid and influenza antigens. RV-CD4 T cell response was enriched in monofunctional IFN-γ + cells, while influenza-CD4 and tetanus toxoid-CD4 T cell responses were enriched in multifunctional T cells. Moreover, rIL-2 – unlike rIL-12 or DGKα-i – increased the frequencies of RV-CD4 TNF-α + , CD4 IFN-γ + , and CD8 IFN-γ + cells. Thus, circulating RV-T cells seem to have a relatively poor functional profile that may be partially reversed in vitro by the addition of rIL-2. - Highlights: • The quality and magnitude of circulating RV-T cell responses are relatively poor. • Circulating RV-CD4 T cells are enriched in monofunctional IFN-γ+ cells. • Treatment with rIL-2 increased the frequencies of cytokine secreting RV-T cells

  8. Proliferation requirements of cytomegalovirus-specific, effector-type human CD8+ T cells

    NARCIS (Netherlands)

    van Leeuwen, Ester M.; Gamadia, Laila E.; Baars, Paul A.; Remmerswaal, Ester B.; ten Berge, Ineke J.; van Lier, René A.

    2002-01-01

    Two prototypic types of virus-specific CD8(+) T cells can be found in latently infected individuals: CD45R0(+)CD27(+)CCR7(-) effector-memory, and CD45RA(+)CD27(-)CCR7(-) effector-type cells. It has recently been implied that CD45RA(+)CD27(-)CCR7(-) T cells are terminally differentiated effector

  9. New insights into Notch1 regulation of the PI3K-AKT-mTOR1 signaling axis: targeted therapy of γ-secretase inhibitor resistant T-cell acute lymphoblastic leukemia.

    Science.gov (United States)

    Hales, Eric C; Taub, Jeffrey W; Matherly, Larry H

    2014-01-01

    T-cell acute lymphoblastic leukemia (T-ALL) is characterized as a high-risk stratified disease associated with frequent relapse, chemotherapy resistance, and a poorer prognostic outlook than B-precursor ALL. Many of the challenges in treating T-ALL reflect the lack of prognostic cytogenetic or molecular abnormalities on which to base therapy, including targeted therapy. Notch1 activating mutations were identified in more than 50% of T-ALL cases and can be therapeutically targeted with γ-secretase inhibitors (GSIs). Mutant Notch1 can activate cMyc and PI3K-AKT-mTOR1 signaling in T-ALL. In T-ALLs with wild-type phosphatase and tensin homolog deleted on chromosome ten (PTEN), Notch1 transcriptionally represses PTEN, an effect reversible by GSIs. Notch1 also promotes growth factor receptor (IGF1R and IL7Rα) signaling to PI3K-AKT. Loss of PTEN is common in primary T-ALLs due to mutation or posttranslational inactivation and results in chronic activation of PI3K-AKT-mTOR1 signaling, GSI-resistance, and repression of p53-mediated apoptosis. Notch1 itself might regulate posttranslational inactivation of PTEN. PP2A is activated by Notch1 in PTEN-null T-ALL cells, and GSIs reduce PP2A activity and increase phosphorylation of AKT, AMPK, and p70S6K. This review focuses on the central role of the PI3K-AKT-mTOR1 signaling in T-ALL, including its regulation by Notch1 and potential therapeutic interventions, with emphasis on GSI-resistant T-ALL. © 2013.

  10. T-cell help permits memory CD8(+) T-cell inflation during cytomegalovirus latency.

    Science.gov (United States)

    Walton, Senta M; Torti, Nicole; Mandaric, Sanja; Oxenius, Annette

    2011-08-01

    CD4(+) T cells are implied to sustain CD8(+) T-cell responses during persistent infections. As CD4(+) T cells are often themselves antiviral effectors, they might shape CD8(+) T-cell responses via help or via controlling antigen load. We used persistent murine CMV (MCMV) infection to dissect the impact of CD4(+) T cells on virus-specific CD8(+) T cells, distinguishing between increased viral load in the absence of CD4(+) T cells and CD4(+) T-cell-mediated helper mechanisms. Absence of T-helper cells was associated with sustained lytic MCMV replication and led to a slow and gradual reduction of the size and function of the MCMV-specific CD8(+) T-cell pool. However, when virus replication was controlled in the absence of CD4(+) T cells, CD8(+) T-cell function was comparably impaired, but in addition CD8(+) T-cell inflation, a hallmark of CMV infection, was completely abolished. Thus, CD8(+) T-cell inflation during latent CMV infection is strongly dependent on CD4(+) T-cell helper functions, which can partially be compensated by ongoing lytic viral replication in the absence of CD4(+) T cells. Copyright © 2011 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  11. The IL-33-ST2-MyD88 axis promotes regulatory T cell proliferation in the murine liver.

    Science.gov (United States)

    Xu, Lei; Li, Wei; Wang, Xiaofan; Zhang, Lina; Qi, Qianqian; Dong, Liyang; Wei, Chuan; Pu, Yanan; Li, Yalin; Zhu, Jifeng; Zhou, Sha; Liu, Feng; Chen, Xiaojun; Su, Chuan

    2018-05-05

    Hepatic Foxp3 + regulatory T (Treg) cells are crucial for maintaining local immune homeostasis in the liver. However, the environmental cues required for hepatic Treg cell homeostasis are unclear. In this study, we showed that the IL-33 receptor ST2 was preferentially expressed on Treg cells in the mouse liver, but it was more lowly expressed in the spleen, mesenteric lymph nodes, and blood. More importantly, we found that IL-33 promoted the proliferation of hepatic Treg cells through myeloid differentiation factor MyD88 signaling concomitant with increased CDK4 and cyclin D1 expression. These results suggested that IL-33 is a potential tissue-specific factor controlling Treg cell homeostasis via increased Treg proliferation in the liver. This article is protected by copyright. All rights reserved. This article is protected by copyright. All rights reserved.

  12. A role for adhesion molecules in contact-dependent T help for B cells

    DEFF Research Database (Denmark)

    Owens, T

    1991-01-01

    The role of cell contact in T-dependent B cell activation was examined. Small resting B cells from C57BL/6 mice were cultured with CBA-derived, non-alloreactive cloned T helper cells in anti-T cell receptor V beta 8-coated microwells. This induced polyclonal B cell activation to enter cell cycle...... that continued cell contact involving adhesion/accessory molecules induces B cells to proliferate and to respond to T cell lymphokines. A signaling role for cell interaction molecules on B cells is proposed, similar to the role of these and analogous molecules on T cells....

  13. Paediatric B-cell precursor acute lymphoblastic leukaemia with t(1;19)(q23;p13): clinical and cytogenetic characteristics of 47 cases from the Nordic countries treated according to NOPHO protocols

    DEFF Research Database (Denmark)

    Andersen, Mette Klarskov; Autio, Kirsi; Barbany, Gisela

    2011-01-01

    The translocation t(1;19)(q23;p13)/der(19)t(1;19) is a risk stratifying aberration in childhood B-cell precursor acute lymphoblastic leukaemia (BCP ALL) in the Nordic countries. We have identified 47 children/adolescents with t(1;19)/der(19)t(1;19)-positive BCP ALL treated on two successive Nordic...... Society of Paediatric Haematology and Oncology (NOPHO) protocols between 1992 and 2007 and have reviewed the clinical and cytogenetic characteristics of these cases, comprising 1·8% of all cases. The translocation was balanced in 15 cases (32%) and unbalanced in 29 cases (62%). The most common additional...... and 10 years was 0·85 and 0·82, respectively. Nine patients had a bone marrow relapse after a median of 23 months; no patient had a central nervous system relapse. Additional cytogenetic abnormalities, age, gender, WBC count or whether the t(1;19) was balanced or unbalanced did not influence EFS or OS...

  14. Real-time tracking of cell cycle progression during CD8+ effector and memory T-cell differentiation.

    Science.gov (United States)

    Kinjyo, Ichiko; Qin, Jim; Tan, Sioh-Yang; Wellard, Cameron J; Mrass, Paulus; Ritchie, William; Doi, Atsushi; Cavanagh, Lois L; Tomura, Michio; Sakaue-Sawano, Asako; Kanagawa, Osami; Miyawaki, Atsushi; Hodgkin, Philip D; Weninger, Wolfgang

    2015-02-24

    The precise pathways of memory T-cell differentiation are incompletely understood. Here we exploit transgenic mice expressing fluorescent cell cycle indicators to longitudinally track the division dynamics of individual CD8(+) T cells. During influenza virus infection in vivo, naive T cells enter a CD62L(intermediate) state of fast proliferation, which continues for at least nine generations. At the peak of the anti-viral immune response, a subpopulation of these cells markedly reduces their cycling speed and acquires a CD62L(hi) central memory cell phenotype. Construction of T-cell family division trees in vitro reveals two patterns of proliferation dynamics. While cells initially divide rapidly with moderate stochastic variations of cycling times after each generation, a slow-cycling subpopulation displaying a CD62L(hi) memory phenotype appears after eight divisions. Phenotype and cell cycle duration are inherited by the progeny of slow cyclers. We propose that memory precursors cell-intrinsically modulate their proliferative activity to diversify differentiation pathways.

  15. Circulating rotavirus-specific T cells have a poor functional profile.

    Science.gov (United States)

    Parra, Miguel; Herrera, Daniel; Jácome, María Fernanda; Mesa, Martha C; Rodríguez, Luz-Stella; Guzmán, Carolina; Angel, Juana; Franco, Manuel A

    2014-11-01

    Frequencies of circulating T cells producing IFN-γ, TNF-α, and IL-2, and percentages of T cells proliferating after stimulation with rotavirus (RV), tetanus toxoid, and influenza were evaluated in PBMC derived from healthy adults and children. In addition, the potential anergic state of RV-specific T cells was analyzed by stimulation of PBMC with RV antigen in the presence of three anergy inhibitors (rIL-2, rIL-12, or DGKα-i). The quality and magnitude of RV-T cell responses were significantly lower than those of tetanus toxoid and influenza antigens. RV-CD4 T cell response was enriched in monofunctional IFN-γ(+) cells, while influenza-CD4 and tetanus toxoid-CD4 T cell responses were enriched in multifunctional T cells. Moreover, rIL-2--unlike rIL-12 or DGKα-i--increased the frequencies of RV-CD4 TNF-α(+), CD4 IFN-γ(+), and CD8 IFN-γ(+) cells. Thus, circulating RV-T cells seem to have a relatively poor functional profile that may be partially reversed in vitro by the addition of rIL-2. Copyright © 2014 Elsevier Inc. All rights reserved.

  16. Pivotal advance: CTLA-4+ T cells exhibit normal antiviral functions during acute viral infection.

    Science.gov (United States)

    Raué, Hans-Peter; Slifka, Mark K

    2007-05-01

    Previous studies have shown that T cells, which are genetically deficient in CTLA-4/CD152 expression, will proliferate uncontrollably, resulting in lethal autoimmune disease. This and other evidence indicate that CTLA-4 plays a critical role in the negative regulation of effector T cell function. In contrast to expectations, BrdU incorporation experiments demonstrated that CTLA-4 expression was associated with normal or even enhanced in vivo proliferation of virus-specific CD4+ and CD8+ T cells following acute lymphocytic choriomeningitis virus or vaccinia virus infection. When compared with CTLA-4- T cells directly ex vivo, CTLA-4+ T cells also exhibited normal antiviral effector functions following stimulation with peptide-coated cells, virus-infected cells, plate-bound anti-CD3/anti-CTLA-4, or the cytokines IL-12 and IL-18. Together, this indicates that CTLA-4 does not directly inhibit antiviral T cell expansion or T cell effector functions, at least not under the normal physiological conditions associated with either of these two acute viral infections.

  17. Manufacturing validation of biologically functional T cells targeted to CD19 antigen for autologous adoptive cell therapy

    Science.gov (United States)

    Hollyman, Daniel; Stefanski, Jolanta; Przybylowski, Mark; Bartido, Shirley; Borquez-Ojeda, Oriana; Taylor, Clare; Yeh, Raymond; Capacio, Vanessa; Olszewska, Malgorzata; Hosey, James; Sadelain, Michel; Brentjens, Renier J.; Rivière, Isabelle

    2009-01-01

    Summary Based on promising pre-clinical data demonstrating the eradication of systemic B cell malignancies by CD19-targeted T lymphocytes in vivo in SCID beige mouse models, we are launching Phase 1 clinical trials in patients with chronic lymphocytic leukemia (CLL) and acute lymphoblastic leukemia (ALL). We present here the validation of the bioprocess we developed for the production and expansion of clinical grade autologous T cells derived from patients with CLL. We demonstrate that T cells genetically modified with a replication-defective gammaretroviral vector derived from the Moloney murine leukemia virus encoding a chimeric antigen receptor (CAR) targeted to CD19 (1928z) can be expanded with Dynabeads® CD3/CD28. This bioprocess allows us to generate clinical doses of 1928z+ T cells in approximately 2 to 3 weeks in a large-scale semi-closed culture system using the Wave bioreactor. These 1928z+ T cells remain biologically functional not only in vitro but also in SCID beige mice bearing disseminated tumors. The validation requirements in terms of T cell expansion, T cell transduction with the 1928z CAR, biological activity, quality control testing and release criteria were met for all four validation runs using apheresis products from patients with CLL. Additionally, following expansion of the T cells, the diversity of the skewed Vβ T cell receptor repertoire was significantly restored. This validated process will be used in phase I clinical trials in patients with chemo-refractory CLL and in patients with relapsed ALL. It can also be adapted for other clinical trials involving the expansion and transduction of patient or donor T cells using any chimeric antigen receptor or T cell receptor. PMID:19238016

  18. CD4+ T Cells Mediate Aspergillosis Vaccine Protection.

    Science.gov (United States)

    Diaz-Arevalo, Diana; Kalkum, Markus

    2017-01-01

    Adaptive effector CD4 + T cells play essential roles in the defense against fungal infections, especially against invasive aspergillosis (IA). Such protective CD4 + T cells can be generated through immunization with specialized antifungal vaccines, as has been demonstrated for pulmonary Aspergillus fumigatus infections in mouse experiments. Adaptive transfer of fungal antigen-specific CD4 + T cells conferred protection onto non-immunized naive mice, an experimental approach that could potentially become a future treatment option for immunosuppressed IA patients, focusing on the ultimate goal to improve their otherwise dim chances for survival. Here, we describe the different techniques to analyze CD4 + T cell immune responses after immunization with a recombinant fungal protein. We present three major methods that are used to analyze the role of CD4 + T cells in protection against A. fumigatus challenge. They include (1) transplantation of CD4 + T cells from vaccinated mice into immunosuppressed naive mice, observing increasing protection of the cell recipients, (2) depletion of CD4 + T cells from vaccinated mice, which abolishes vaccine protection, and (3) T cell proliferation studies following stimulation with overlapping synthetic peptides or an intact protein vaccine. The latter can be used to validate immunization status and to identify protective T cell epitopes in vaccine antigens. In the methods detailed here, we used versions of the well-studied Asp f3 protein expressed in a bacterial host, either as the intact full length protein or its N-terminally truncated version, comprised of residues 15-168. However, these methods are generally applicable and can well be adapted to study other protein-based subunit vaccines.

  19. Genetically-modified pig mesenchymal stromal cells: xenoantigenicity and effect on human T-cell xenoresponses.

    Science.gov (United States)

    Ezzelarab, Mohamed; Ezzelarab, Corin; Wilhite, Tyler; Kumar, Goutham; Hara, Hidetaka; Ayares, David; Cooper, David K C

    2011-01-01

    Mesenchymal stromal cells (MSC) are being investigated as immunomodulatory therapy in the field of transplantation, particularly islet transplantation. While MSC can regenerate across species barriers, the immunoregulatory influence of genetically modified pig MSC (pMSC) on the human and non-human primate T-cell responses has not been studied. Mesenchymal stromal cells from wild-type (WT), α1,3-galactosyltransferase gene knockout (GTKO) and GTKO pigs transgenic for the human complement-regulatory protein CD46 (GTKO/CD46) were isolated and tested for differentiation. Antibody binding and T-cell responses to WT and GTKO pMSC in comparison with GTKO pig aortic endothelial cells (pAEC) were investigated. The expression of swine leukocyte antigen (SLA) class II (SLA II) was tested. Costimulatory molecules CD80 and CD86 mRNA levels were measured. Human T-cell proliferation and the production of pro-inflammatory cytokines in response to GTKO and GTKO/CD46 pMSC in comparison with human MSC (hMSC) were evaluated. α1,3-galactosyltransferase gene knockout and GTKO/CD46 pMSC isolation and differentiation were achieved in vitro. Binding of human antibodies and T-cell responses were lower to GTKO than those to WT pMSC. Human and baboon (naïve and sensitized) antibody binding were significantly lower to GTKO pMSC than to GTKO pAEC. Before activation, human CD4(+) T-cell response to GTKO pMSC was significantly weaker than that to GTKO pAEC, even after pIFN-γ activation. More than 99% of GTKO/CD46 pMSC expressed hCD46. Human peripheral blood mononuclear cells and CD4(+) T-cell responses to GTKO and GTKO/CD46 pMSC were comparable with those to hMSC, and all were significantly lower than to GTKO pAEC. GTKO/CD46 pMSC downregulated human T-cell proliferation as efficiently as hMSC. The level of proinflammatory cytokines IL-2, IFN-γ, TNF-α, and sCD40L correlated with the downregulation of T-cell proliferation by all types of MSC. Genetically modified pMSC is significantly less

  20. Natural autoantibodies and complement promote the uptake of a self antigen, human thyroglobulin, by B cells and the proliferation of thyroglobulin-reactive CD4(+) T cells in healthy individuals

    DEFF Research Database (Denmark)

    Nielsen, C H; Leslie, R G; Jepsen, B S

    2001-01-01

    of complement receptor types 1 (CR1, CD35) and 2 (CR2, CD21). T cell responsiveness to Tg was examined in a preparation of peripheral blood mononuclear cells (PBMC) cultured in the presence of autologous serum. A subset of CD4(+) T cells exhibited a dose-dependent proliferative response to Tg, which...... cells are prerequisites for the proliferation of Tg-reactive CD4(+) T cells, suggesting a novel role for natural autoantibodies and complement in the regulation of autoreactivity under physiological conditions....... was strongly inhibited by complement inactivation and by immunoabsorption of Tg-reactive antibodies. Furthermore, this T cell response was abrogated by depletion of B cells from the PBMC culture. These data imply that uptake of complement-opsonized Tg / anti-Tg complexes and subsequent presentation of Tg by B...

  1. Virus-specific regulatory T cells ameliorate encephalitis by repressing effector T cell functions from priming to effector stages.

    Directory of Open Access Journals (Sweden)

    Jingxian Zhao

    2014-08-01

    Full Text Available Several studies have demonstrated the presence of pathogen-specific Foxp3+ CD4 regulatory T cells (Treg in infected animals, but little is known about where and how these cells affect the effector T cell responses and whether they are more suppressive than bulk Treg populations. We recently showed the presence of both epitope M133-specific Tregs (M133 Treg and conventional CD4 T cells (M133 Tconv in the brains of mice with coronavirus-induced encephalitis. Here, we provide new insights into the interactions between pathogenic Tconv and Tregs responding to the same epitope. M133 Tregs inhibited the proliferation but not initial activation of M133 Tconv in draining lymph nodes (DLN. Further, M133 Tregs inhibited migration of M133 Tconv from the DLN. In addition, M133 Tregs diminished microglia activation and decreased the number and function of Tconv in the infected brain. Thus, virus-specific Tregs inhibited pathogenic CD4 T cell responses during priming and effector stages, particularly those recognizing cognate antigen, and decreased mortality and morbidity without affecting virus clearance. These cells are more suppressive than bulk Tregs and provide a targeted approach to ameliorating immunopathological disease in infectious settings.

  2. CP-25 Attenuates the Activation of CD4+ T Cells Stimulated with Immunoglobulin D in Human.

    Science.gov (United States)

    Wu, Yu-Jing; Chen, Heng-Shi; Chen, Wen-Sheng; Dong, Jin; Dong, Xiao-Jie; Dai, Xing; Huang, Qiong; Wei, Wei

    2018-01-01

    Researchers have shown that the level of immunoglobulin D (IgD) is often elevated in patients with autoimmune diseases. The possible roles of IgD on the function of human T cell activation are still unclear. Paeoniflorin-6'- O -benzene sulfonate (code: CP-25), the chemistry structural modifications of paeoniflorin, was a novel drug of anti-inflammation and immunomodulation. The aims of this study were to determine if human CD4 + T cells could be activated by IgD via the IgD receptor (IgDR)-Lck pathway and whether the novel compound CP-25 could affect the activation of T cells by regulating Lck. Human CD4 + T cells were purified from peripheral blood mononuclear cells using microbeads. T cell viability and proliferation were detected by Cell Counting Kit-8 and CFSE Cell Proliferation Kit. Cytokines secreted by T cells were assessed with the Quantibody Human Inflammation Array. The binding affinity and expression of IgDR on T cells were detected by flow cytometry, and protein expression of IgDR, Lck, and P-Lck were analyzed by western blot. IgD was shown to bind to IgDR on CD4 + T cells in a concentration-dependent manner and stimulate the activation and proliferation of these cells by enhancing phosphorylation of the activating tyrosine residue of Lck (Tyr 394 ). CP-25 inhibited the IgD-stimulated activation and proliferation of CD4 + T cells, as well as the production of inflammatory cytokines; it was thus suggested that this process might be related to the downregulation of Lck (Tyr 394 ) phosphorylation. These results demonstrate that IgD amplifies the activation of CD4 + T cells, which could be mediated by Lck phosphorylation. Further, CP-25, via its ability to modulate Lck, is a novel potential therapeutic agent for the treatment of human autoimmune diseases.

  3. T Cell Responses: Naive to Memory and Everything in Between

    Science.gov (United States)

    Pennock, Nathan D.; White, Jason T.; Cross, Eric W.; Cheney, Elizabeth E.; Tamburini, Beth A.; Kedl, Ross M.

    2013-01-01

    The authors describe the actions that take place in T cells because of their amazing capacity to proliferate and adopt functional roles aimed at clearing a host of an infectious agent. There is a drastic decline in the T cell population once the primary response is over and the infection is terminated. What remains afterward is a population of T…

  4. Homeostatic Proliferation and IL-7R Alpha Expression Do Not Correlate with Enhanced T Cell Proliferation and Protection in Chronic Mouse Malaria

    OpenAIRE

    Stephens, Robin; Seddon, Benedict; Langhorne, Jean

    2011-01-01

    While chronic infection has been shown to enhance protection from disease caused by several pathogens, the mechanisms are not known. The gamma-c family of cytokines IL-7, IL-2, and IL-15 are implicated in homeostatic proliferation, which is thought to maintain T cell memory. However in chronic infection, prolonged antigen exposure itself may contribute to lymphocyte survival. We have previously observed that chronic malaria infection enhances protection to re-infection, as well as enhancing B...

  5. Circulating rotavirus-specific T cells have a poor functional profile

    Energy Technology Data Exchange (ETDEWEB)

    Parra, Miguel; Herrera, Daniel [Instituto de Genética Humana, Facultad de Medicina, Pontificia Universidad Javeriana, Pontificia Universidad Javeriana, Carrera 7 # 40-62, Bogotá (Colombia); Jácome, María Fernanda; Mesa, Martha C. [Departamento de Microbiología, Facultad de Ciencias, Pontificia Universidad Javeriana, Bogotá (Colombia); Rodríguez, Luz-Stella [Instituto de Genética Humana, Facultad de Medicina, Pontificia Universidad Javeriana, Pontificia Universidad Javeriana, Carrera 7 # 40-62, Bogotá (Colombia); Guzmán, Carolina [Departamento de Pediatría, Hospital Universitario San Ignacio, Facultad de Medicina, Pontificia Universidad Javeriana, Bogotá (Colombia); Angel, Juana; Franco, Manuel A. [Instituto de Genética Humana, Facultad de Medicina, Pontificia Universidad Javeriana, Pontificia Universidad Javeriana, Carrera 7 # 40-62, Bogotá (Colombia)

    2014-11-15

    Frequencies of circulating T cells producing IFN-γ, TNF-α, and IL-2, and percentages of T cells proliferating after stimulation with rotavirus (RV), tetanus toxoid, and influenza were evaluated in PBMC derived from healthy adults and children. In addition, the potential anergic state of RV-specific T cells was analyzed by stimulation of PBMC with RV antigen in the presence of three anergy inhibitors (rIL-2, rIL-12, or DGKα-i). The quality and magnitude of RV-T cell responses were significantly lower than those of tetanus toxoid and influenza antigens. RV-CD4 T cell response was enriched in monofunctional IFN-γ{sup +} cells, while influenza-CD4 and tetanus toxoid-CD4 T cell responses were enriched in multifunctional T cells. Moreover, rIL-2 – unlike rIL-12 or DGKα-i – increased the frequencies of RV-CD4 TNF-α{sup +}, CD4 IFN-γ{sup +}, and CD8 IFN-γ{sup +} cells. Thus, circulating RV-T cells seem to have a relatively poor functional profile that may be partially reversed in vitro by the addition of rIL-2. - Highlights: • The quality and magnitude of circulating RV-T cell responses are relatively poor. • Circulating RV-CD4 T cells are enriched in monofunctional IFN-γ+ cells. • Treatment with rIL-2 increased the frequencies of cytokine secreting RV-T cells.

  6. IL-15 augments TCR-induced CD4+ T cell expansion in vitro by inhibiting the suppressive function of CD25 High CD4+ T cells.

    Directory of Open Access Journals (Sweden)

    Tom L Van Belle

    Full Text Available Due to its critical role in NK cell differentiation and CD8(+ T cell homeostasis, the importance of IL-15 is more firmly established for cytolytic effectors of the immune system than for CD4(+ T cells. The increased levels of IL-15 found in several CD4(+ T cell-driven (auto- immune diseases prompted us to examine how IL-15 influences murine CD4(+ T cell responses to low dose TCR-stimulation in vitro. We show that IL-15 exerts growth factor activity on both CD4(+ and CD8(+ T cells in a TCR-dependent and Cyclosporin A-sensitive manner. In CD4(+ T cells, IL-15 augmented initial IL-2-dependent expansion and once IL-15Rα was upregulated, IL-15 sustained the TCR-induced expression of IL-2/15Rβ, supporting proliferation independently of secreted IL-2. Moreover, IL-15 counteracts CD4(+ T cell suppression by a gradually expanding CD25(HighCD4(+ T cell subset that expresses Foxp3 and originates from CD4(+CD25(+ Tregs. These in vitro data suggest that IL-15 may dramatically strengthen the T cell response to suboptimal TCR-triggering by overcoming an activation threshold set by Treg that might create a risk for autoimmune pathology.

  7. Adiponectin and AMP kinase activator stimulate proliferation, differentiation, and mineralization of osteoblastic MC3T3-E1 cells

    Directory of Open Access Journals (Sweden)

    Yamauchi Mika

    2007-11-01

    Full Text Available Abstract Background Adiponectin is a key mediator of the metabolic syndrome that is caused by visceral fat accumulation. Adiponectin and its receptors are known to be expressed in osteoblasts, but their actions with regard to bone metabolism are still unclear. In this study, we investigated the effects of adiponectin on the proliferation, differentiation, and mineralization of osteoblastic MC3T3-E1 cells. Results Adiponectin receptor type 1 (AdipoR1 mRNA was detected in the cells by RT-PCR. The adenosine monophosphate-activated protein kinase (AMP kinase was phosphorylated by both adiponectin and a pharmacological AMP kinase activator, 5-amino-imidazole-4-carboxamide-riboside (AICAR, in the cells. AdipoR1 small interfering RNA (siRNA transfection potently knocked down the receptor mRNA, and the effect of this knockdown persisted for as long as 10 days after the transfection. The transfected cells showed decreased expressions of type I collagen and osteocalcin mRNA, as determined by real-time PCR, and reduced ALP activity and mineralization, as determined by von Kossa and Alizarin red stainings. In contrast, AMP kinase activation by AICAR (0.01–0.5 mM in wild-type MC3T3-E1 cells augmented their proliferation, differentiation, and mineralization. BrdU assay showed that the addition of adiponectin (0.01–1.0 μg/ml also promoted their proliferation. Osterix, but not Runx-2, appeared to be involved in these processes because AdipoR1 siRNA transfection and AICAR treatments suppressed and enhanced osterix mRNA expression, respectively. Conclusion Taken together, this study suggests that adiponectin stimulates the proliferation, differentiation, and mineralization of osteoblasts via the AdipoR1 and AMP kinase signaling pathways in autocrine and/or paracrine fashions.

  8. Downregulation of IL-12 and a novel negative feedback system mediated by CD25+CD4+ T cells

    International Nuclear Information System (INIS)

    Sato, Kojiro; Tateishi, Shoko; Kubo, Kanae; Mimura, Toshihide; Yamamoto, Kazuhiko; Kanda, Hiroko

    2005-01-01

    CD25 + CD4 + regulatory T cells suppress immune responses and are believed to play roles in preventing autoimmune diseases. However, the mechanism(s) underlying the suppression and the regulation of their homeostasis remain to be elucidated. Here we show that these regulatory T cells downregulated CD25 - CD4 + T-cell-mediated production of IL-12 from antigen-presenting cells, which can act as a growth factor for CD25 - CD4 + T cells. We further found that CD25 + CD4 + T cells, despite their well-documented 'anergic' nature, proliferate significantly in vitro only when CD25 - CD4 + T cells are present. Notably, this proliferation was strongly dependent on IL-2 and relatively independent of IL-12. Thus, CD25 + CD4 + T cells suppress CD25 - CD4 + T-cell responses, at least in part, by inhibiting IL-12 production while they themselves can undergo proliferation with the mediation of CD25 - CD4 + T cells in vitro. These results offer a novel negative feedback system involving a tripartite interaction among CD25 + CD4 + and CD25 - CD4 + T cells, and APCs that may contribute to the termination of immune responses

  9. T-cell receptor transfer into human T cells with ecotropic retroviral vectors.

    Science.gov (United States)

    Koste, L; Beissert, T; Hoff, H; Pretsch, L; Türeci, Ö; Sahin, U

    2014-05-01

    Adoptive T-cell transfer for cancer immunotherapy requires genetic modification of T cells with recombinant T-cell receptors (TCRs). Amphotropic retroviral vectors (RVs) used for TCR transduction for this purpose are considered safe in principle. Despite this, TCR-coding and packaging vectors could theoretically recombine to produce replication competent vectors (RCVs), and transduced T-cell preparations must be proven free of RCV. To eliminate the need for RCV testing, we transduced human T cells with ecotropic RVs so potential RCV would be non-infectious for human cells. We show that transfection of synthetic messenger RNA encoding murine cationic amino-acid transporter 1 (mCAT-1), the receptor for murine retroviruses, enables efficient transient ecotropic transduction of human T cells. mCAT-1-dependent transduction was more efficient than amphotropic transduction performed in parallel, and preferentially targeted naive T cells. Moreover, we demonstrate that ecotropic TCR transduction results in antigen-specific restimulation of primary human T cells. Thus, ecotropic RVs represent a versatile, safe and potent tool to prepare T cells for the adoptive transfer.

  10. T cell resistance to activation by dendritic cells requires long-term culture in simulated microgravity

    Science.gov (United States)

    Bradley, Jillian H.; Stein, Rachel; Randolph, Brad; Molina, Emily; Arnold, Jennifer P.; Gregg, Randal K.

    2017-11-01

    Immune impairment mediated by microgravity threatens the success of space exploration requiring long-duration spaceflight. The cells of most concern, T lymphocytes, coordinate the host response against microbial and cancerous challenges leading to elimination and long-term protection. T cells are activated upon recognition of specific microbial peptides bound on the surface of antigen presenting cells, such as dendritic cells (DC). Subsequently, this engagement results in T cell proliferation and differentiation into effector T cells driven by autocrine interleukin-2 (IL-2) and other cytokines. Finally, the effector T cells acquire the weaponry needed to destroy microbial invaders and tumors. Studies conducted on T cells during spaceflight, or using Earth-based culture systems, have shown reduced production of cytokines, proliferation and effector functions as compared to controls. This may account for the cases of viral reactivation events and opportunistic infections associated with astronauts of numerous missions. This work has largely been based upon the outcome of T cell activation by stimulatory factors that target select T cell signaling pathways rather than the complex, signaling events related to the natural process of antigen presentation by DC. This study tested the response of an ovalbumin peptide-specific T cell line, OT-II TCH, to activation by DC when the T cells were cultured 24-120 h in a simulated microgravity (SMG) environment generated by a rotary cell culture system. Following 72 h culture of T cells in SMG (SMG-T) or control static (Static-T) conditions, IL-2 production by the T cells was reduced in SMG-T cells compared to Static-T cells upon stimulation by phorbol 12-myristate 13-acetate (PMA) and ionomycin. However, when the SMG-T cells were stimulated with DC and peptide, IL-2 was significantly increased compared to Static-T cells. Such enhanced IL-2 production by SMG-T cells peaked at 72 h SMG culture time and decreased thereafter. When

  11. Changes in Reactivity In Vitro of CD4+CD25+ and CD4+CD25− T Cell Subsets in Transplant Tolerance

    Science.gov (United States)

    Hall, Bruce M.; Robinson, Catherine M.; Plain, Karren M.; Verma, Nirupama D.; Tran, Giang T.; Nomura, Masaru; Carter, Nicole; Boyd, Rochelle; Hodgkinson, Suzanne J.

    2017-01-01

    Transplant tolerance induced in adult animals is mediated by alloantigen-specific CD4+CD25+ T cells, yet in many models, proliferation of CD4+ T cells from hosts tolerant to specific-alloantigen in vitro is not impaired. To identify changes that may diagnose tolerance, changes in the patterns of proliferation of CD4+, CD4+CD25+, and CD4+CD25− T cells from DA rats tolerant to Piebald Virol Glaxo rat strain (PVG) cardiac allografts and from naïve DA rats were examined. Proliferation of CD4+ T cells from both naïve and tolerant hosts was similar to both PVG and Lewis stimulator cells. In mixed lymphocyte culture to PVG, proliferation of naïve CD4+CD25− T cells was greater than naïve CD4+ T cells. In contrast, proliferation of CD4+CD25− T cells from tolerant hosts to specific-donor PVG was not greater than CD4+ T cells, whereas their response to Lewis and self-DA was greater than CD4+ T cells. Paradoxically, CD4+CD25+ T cells from tolerant hosts did not proliferate to PVG, but did to Lewis, whereas naïve CD4+CD25+ T cells proliferate to both PVG and Lewis but not to self-DA. CD4+CD25+ T cells from tolerant, but not naïve hosts, expressed receptors for interferon (IFN)-γ and IL-5 and these cytokines promoted their proliferation to specific-alloantigen PVG but not to Lewis or self-DA. We identified several differences in the patterns of proliferation to specific-donor alloantigen between cells from tolerant and naïve hosts. Most relevant is that CD4+CD25+ T cells from tolerant hosts failed to proliferate or suppress to specific donor in the absence of either IFN-γ or IL-5. The proliferation to third-party and self of each cell population from tolerant and naïve hosts was similar and not affected by IFN-γ or IL-5. Our findings suggest CD4+CD25+ T cells that mediate transplant tolerance depend on IFN−γ or IL-5 from alloactivated Th1 and Th2 cells. PMID:28878770

  12. B-cell-rich T-cell lymphoma associated with Epstein-Barr virus-reactivation and T-cell suppression following antithymocyte globulin therapy in a patient with severe aplastic anemia

    Directory of Open Access Journals (Sweden)

    Nobuyoshi Hanaoka

    2015-09-01

    Full Text Available B-cell lymphoproliferative disorder (B-LPD is generally characterized by the proliferation of Epstein-Barr virus (EBV-infected B lymphocytes. We here report the development of EBV-negative B-LPD associated with EBV-reactivation following antithymocyte globulin (ATG therapy in a patient with aplastic anemia. The molecular autopsy study showed the sparse EBV-infected clonal T cells could be critically involved in the pathogenesis of EBV-negative oligoclonal B-LPD through cytokine amplification and escape from T-cell surveillances attributable to ATG-based immunosuppressive therapy, leading to an extremely rare B-cell-rich T-cell lymphoma. This report helps in elucidating the complex pathophysiology of intractable B-LPD refractory to rituximab.

  13. Cellular interactions of synovial fluid γδ T cells in juvenile idiopathic arthritis.

    Science.gov (United States)

    Bendersky, Anna; Marcu-Malina, Victoria; Berkun, Yackov; Gerstein, Maya; Nagar, Meital; Goldstein, Itamar; Padeh, Shai; Bank, Ilan

    2012-05-01

    The pathogenesis of juvenile idiopathic arthritis (JIA) is thought to involve multiple components of the cellular immune system, including subsets of γδ T cells. In this study, we conducted experiments to define the functional roles of one of the major synovial fluid (SF) T cell subsets, Vγ9(+)Vδ2(+) (Vγ9(+)) T cells, in JIA. We found that as opposed to CD4(+) T cells, equally high percentages (∼35%) of Vγ9(+) T cells in SF and peripheral blood (PB) produced TNF-α and IFN-γ. Furthermore, stimulation with isopentenyl pyrophosphate (IPP), a metabolite in the mevalonate pathway, which is a specific potent Ag for Vγ9Jγ1.2(+) T cells, similarly amplified cytokine secretion by SF and PB Vγ9(+) T cells. Significantly, the SF subset expressed higher levels of CD69 in situ, suggesting their recent activation. Furthermore, 24-h coculturing with SF-derived fibroblasts enhanced CD69 on the SF > PB Vγ9(+) T cells, a phenomenon strongly augmented by zoledronate, a farnesyl pyrophosphate synthase inhibitor that increases endogenous intracellular IPP. Importantly, although Vγ9(+) T cell proliferation in response to IPP was significantly lower in SF than PBMC cultures, it could be enhanced by depleting SF CD4(+)CD25(+)FOXP3(+) cells (regulatory T cells). Furthermore, coculture with the Vγ9(+) T cells in medium containing zoledronate or IPP strongly increased SF-derived fibroblasts' apoptosis. The findings that IPP-responsive proinflammatory synovial Vγ9(+) T cells for which proliferation is partly controlled by regulatory T cells can recognize and become activated by SF fibroblasts and then induce their apoptosis suggest their crucial role in the pathogenesis and control of synovial inflammation.

  14. TCR down-regulation controls virus-specific CD8+ T cell responses

    DEFF Research Database (Denmark)

    Bonefeld, Charlotte Menné; Haks, Mariëlle; Nielsen, Bodil

    2008-01-01

    in mice with a mutated CD3gamma di-leucine-based motif. The CD3gamma mutation did not impair early TCR signaling, nor did it compromise recruitment or proliferation of virus-specific T cells, but it increased the apoptosis rate of the activated T cells by increasing down-regulation of the antiapoptotic...

  15. Induction of CD4 suppressor T cells with anti-Leu-8 antibody

    International Nuclear Information System (INIS)

    Kanof, M.E.; Strober, W.; James, S.P.

    1987-01-01

    To characterize the conditions under which CD4 T cells suppress polyclonal immunoglobulin synthesis, we investigated the capacity of CD4 T cells that coexpress the surface antigen recognized by the monoclonal antibody anti-Leu-8 to mediate suppression. In an in vitro system devoid of CD8 T cells, CD4, Leu-8+ T cells suppressed pokeweed mitogen-induced immunoglobulin synthesis. Similarly, suppressor function was induced in unfractionated CD4 T cell populations after incubation with anti-Leu-8 antibody under cross-linking conditions. This induction of suppressor function by anti-Leu-8 antibody was not due to expansion of the CD4, Leu-8+ T cell population because CD4 T cells did not proliferate in response to anti-Leu-8 antibody. However, CD4, Leu-8+ T cell-mediated suppression was radiosensitive. Finally, CD4, Leu-8+ T cells do not inhibit immunoglobulin synthesis when T cell lymphokines were used in place of helper CD4 T cells (CD4, Leu-8- T cells), suggesting that CD4 T cell-mediated suppression occurs at the T cell level. We conclude that CD4 T cells can be induced to suppress immunoglobulin synthesis by modulation of the membrane antigen recognized by anti-Leu-8 antibody

  16. Glucose metabolism regulates T cell activation, differentiation and functions

    Directory of Open Access Journals (Sweden)

    Clovis Steve Palmer

    2015-01-01

    Full Text Available The adaptive immune system is equipped to eliminate both tumors and pathogenic microorganisms. It requires a series of complex and coordinated signals to drive the activation, proliferation and differentiation of appropriate T cell subsets. It is now established that changes in cellular activation are coupled to profound changes in cellular metabolism. In addition, emerging evidence now suggest that specific metabolic alterations associated with distinct T cell subsets may be ancillary to their differentiation and influential in their immune functions. The Warburg effect originally used to describe a phenomenon in which most cancer cells relied on aerobic glycolysis for their growth is a key process that sustain T cell activation and differentiation. Here we review how different aspects of metabolism in T cells influence their functions, focusing on the emerging role of key regulators of glucose metabolism such as HIF-1α. A thorough understanding of the role of metabolism in T cell function could provide insights into mechanisms involved in inflammatory-mediated conditions, with the potential for developing novel therapeutic approaches to treat these diseases.

  17. [Effects of sintered bone modified with surface mineralization/P24 peptide composite biomaterial on the adhesion, proliferation and osteodifferentiation of MC3T3-E1 cells].

    Science.gov (United States)

    Li, Jingfeng; Zheng, Qixin; Guo, Xiaodong; Chen, Liaobin

    2014-10-01

    In the present research, the effects of sintered bone modified with surface mineralization/P24 peptide composite biomaterials on the adhesion, proliferation and osteodifferentiation of MC3T3-E1 cells were investigated. The experiments were divided into three groups due to biomaterials used: Group A (composite materials of sintered bone modified with surface mineralization and P24, a peptide of bone morphogenetic protein-2); Group B (sintered bone modified with surface mineralization) and Group C (sintered bone only). The three groups were observed by scanning electron microscopy (SEM) before the experiments, respectively. Then MC3T3-E1 cells were cultured on the surfaces of the three kinds of material, respectively. The cell adhesion rate was assessed by precipitation method. The proliferative ability of MC3T3-E1 cells were measured with MTT assay. And the ALP staining and measurement of alkaline phosphatase (ALP) activity were performed to assess the differentiation of cells into osteoblasts. The SEM results showed that the materials in the three groups retained the natural pore structure and the pore sizes were in the range between 200-850 μm. The adhesive ratio measurements and MTT assay suggested that adhesion and proliferation of MC3T3-E1 cells in Group A were much higher than those in Group B and Group C (P bone modified with surface mineralization/P24 composite material was confirmed to improve the adhesion rate and proliferation and osteodifferentiation of MC3T3-E1 cells, and maintained their morphology.

  18. When aging reaches CD4+ T-cells: phenotypic and functional changes

    Directory of Open Access Journals (Sweden)

    Marco Antonio Moro-García

    2013-05-01

    Full Text Available Beyond midlife, the immune system shows aging features and its defensive capability becomes impaired, by a process known as immunosenescence that involves many changes in the innate and adaptive responses. Innate immunity seems to be better preserved globally, while the adaptive immune response exhibits profound age-dependent modifications. Elderly people display a decline in numbers of naïve T-cells in peripheral blood and lymphoid tissues, while, in contrast, their proportion of highly differentiated effector and memory T-cells, such as the CD28null T-cells, increases markedly. Naïve and memory CD4+ T-cells constitute a highly dynamic system with constant homeostatic and antigen-driven proliferation, influx, and loss of T-cells. Thymic activity dwindles with age and essentially ceases in the later decades of life, severely constraining the generation of new T-cells. Homeostatic control mechanisms are very effective at maintaining a large and diverse subset of naïve CD4+ T-cells throughout life, but although later than in CD8+T-cell compartment, these mechanisms ultimately fail with age.

  19. Ptpn11 Deletion in CD4+ Cells Does Not Affect T Cell Development and Functions but Causes Cartilage Tumors in a T Cell-Independent Manner.

    Science.gov (United States)

    Miah, S M Shahjahan; Jayasuriya, Chathuraka T; Salter, Alexander I; Reilly, Emma C; Fugere, Céline; Yang, Wentian; Chen, Qian; Brossay, Laurent

    2017-01-01

    The ubiquitously expressed tyrosine phosphatase Src homology region 2 domain-containing phosphatase-2 (SHP-2, encoded by Ptpn11 ) is required for constitutive cellular processes including proliferation, differentiation, and the regulation of immune responses. During development and maturation, subsets of T cells express a variety of inhibitory receptors known to associate with phosphatases, which in turn, dephosphorylate key players of activating receptor signaling pathways. We hypothesized that SHP-2 deletion would have major effects on T cell development by altering the thresholds for activation, as well as positive and negative selection. Surprisingly, using mice conditionally deficient for SHP-2 in the T cell lineage, we show that the development of these lymphocytes is globally intact. In addition, our data demonstrate that SHP-2 absence does not compromise T cell effector functions, suggesting that SHP-2 is dispensable in these cells. Unexpectedly, in aging mice, Ptpn11 gene deletion driven by CD4 Cre recombinase leads to cartilage tumors in wrist bones in a T cell-independent manner. These tumors resemble miniature cartilaginous growth plates and contain CD4-lineage positive chondrocyte-like cells. Altogether these results indicate that SHP-2 is a cartilage tumor suppressor during aging.

  20. PGE2 suppresses intestinal T cell function in thermal injury: a cause of enhanced bacterial translocation.

    Science.gov (United States)

    Choudhry, M A; Fazal, N; Namak, S Y; Haque, F; Ravindranath, T; Sayeed, M M

    2001-09-01

    Increased gut bacterial translocation in burn and trauma patients has been demonstrated in a number of previous studies, however, the mechanism for such an increased gut bacterial translocation in injured patients remains poorly understood. Utilizing a rat model of burn injury, in the present study we examined the role of intestinal immune defense by analyzing the T cell functions. We investigated if intestinal T cells dysfunction contributes to bacterial translocation after burn injury. Also our study determined if burn-mediated alterations in intestinal T cell functions are related to enhanced release of PGE2. Finally, we examined whether or not burn-related alterations in intestinal T cell function are due to inappropriate activation of signaling molecule P59fyn, which is required for T cell activation and proliferation. The results presented here showed an increase in gut bacterial accumulation in mesenteric lymph nodes after thermal injury. This was accompanied by a decrease in the intestinal T cell proliferative responses. Furthermore, the treatments of burn-injured animals with PGE2 synthesis blocker (indomethacin or NS398) prevented both the decrease in intestinal T cell proliferation and enhanced bacterial translocation. Finally, our data suggested that the inhibition of intestinal T cell proliferation could result via PGE2-mediated down-regulation of the T cell activation-signaling molecule P59fyn. These findings support a role of T cell-mediated immune defense against bacterial translocation in burn injury.

  1. Matrine induced G0/G1 arrest and apoptosis in human acute T-cell lymphoblastic leukemia (T-ALL cells

    Directory of Open Access Journals (Sweden)

    Aslı Tetik Vardarlı

    2018-05-01

    Full Text Available Matrine, a natural product extracted from the root of Sophora flavescens, is a promising alternative drug in different types of cancer. Here, we aimed to investigate the therapeutic effects and underlying molecular mechanisms of matrine on human acute lymphoblastic leukemia (ALL cell line, CCRF-CEM. Cell viability and IC50 values were determined by WST-1 cell cytotoxicity assay. Cell cycle distribution and apoptosis rates were analyzed by flow cytometry. Expression patterns of 44 selected miRNAs and 44 RNAs were analyzed by quantitative reverse transcription polymerase chain reaction (qRT-PCR using the Applied Biosystems 7500 Fast Real-Time PCR System. Matrine inhibited cell viability and induced apoptosis of CCRF-CEM cells in a dose-dependent manner. Cell cycle analysis demonstrated that matrine-treated CCRF-CEM cells significantly accumulated in the G0/G1 phase compared with the untreated control cells. hsa-miR-376b-3p (-37.09 fold, p = 0.008 and hsa-miR-106b-3p (-16.67 fold, p = 0.028 expressions were decreased, whereas IL6 (95.47 fold, p = 0.000011 and CDKN1A (140.03 fold, p = 0.000159 expressions were increased after matrine treatment. Our results suggest that the downregulation of hsa-miR-106b-3p leads to the upregulation of target p21 gene, CDKN1A, and plays a critical role in the cell cycle progression by arresting matrine-treated cells in the G0/G1 phase.

  2. CD8{sup +}CD25{sup +} T cells reduce atherosclerosis in apoE(−/−) mice

    Energy Technology Data Exchange (ETDEWEB)

    Zhou, Jianchang; Dimayuga, Paul C.; Zhao, Xiaoning; Yano, Juliana; Lio, Wai Man; Trinidad, Portia; Honjo, Tomoyuki; Cercek, Bojan; Shah, Prediman K.; Chyu, Kuang-Yuh, E-mail: Chyuk@cshs.org

    2014-01-17

    Highlights: •The role of a sub-population of CD8{sup +} T cells with suppressor functions was investigated in atherosclerosis. •CD8{sup +}CD25{sup +} T cells from adult apoE(−/−) mice had phenotype characteristics of T suppressor cells. •These CD8{sup +}CD25{sup +} T cells reduced CD4{sup +} T cell proliferation and CD8{sup +} cytotoxic activity in vitro. •Adoptive transfer of CD8{sup +}CD25{sup +} T cells significantly reduced atherosclerosis. •CD8{sup +}CD25{sup +} T cells have a suppressive function in atherosclerosis. -- Abstract: Background: It is increasingly evident that CD8{sup +} T cells are involved in atherosclerosis but the specific subtypes have yet to be defined. CD8{sup +}CD25{sup +} T cells exert suppressive effects on immune signaling and modulate experimental autoimmune disorders but their role in atherosclerosis remains to be determined. The phenotype and functional role of CD8{sup +}CD25{sup +} T cells in experimental atherosclerosis were investigated in this study. Methods and results: CD8{sup +}CD25{sup +} T cells were observed in atherosclerotic plaques of apoE(−/−) mice fed hypercholesterolemic diet. Characterization by flow cytometric analysis and functional evaluation using a CFSE-based proliferation assays revealed a suppressive phenotype and function of splenic CD8{sup +}CD25{sup +} T cells from apoE(−/−) mice. Depletion of CD8{sup +}CD25{sup +} from total CD8{sup +} T cells rendered higher cytolytic activity of the remaining CD8{sup +}CD25{sup −} T cells. Adoptive transfer of CD8{sup +}CD25{sup +} T cells into apoE(−/−) mice suppressed the proliferation of splenic CD4{sup +} T cells and significantly reduced atherosclerosis in recipient mice. Conclusions: Our study has identified an athero-protective role for CD8{sup +}CD25{sup +} T cells in experimental atherosclerosis.

  3. The Hayflick Limit May Determine the Effective Clonal Diversity of Naive T Cells.

    Science.gov (United States)

    Ndifon, Wilfred; Dushoff, Jonathan

    2016-06-15

    Having a large number of sufficiently abundant T cell clones is important for adequate protection against diseases. However, as shown in this paper and elsewhere, between young adulthood and >70 y of age the effective clonal diversity of naive CD4/CD8 T cells found in human blood declines by a factor of >10. (Effective clonal diversity accounts for both the number and the abundance of T cell clones.) The causes of this observation are incompletely understood. A previous study proposed that it might result from the emergence of certain rare, replication-enhancing mutations in T cells. In this paper, we propose an even simpler explanation: that it results from the loss of T cells that have attained replicative senescence (i.e., the Hayflick limit). Stochastic numerical simulations of naive T cell population dynamics, based on experimental parameters, show that the rate of homeostatic T cell proliferation increases after the age of ∼60 y because naive T cells collectively approach replicative senescence. This leads to a sharp decline of effective clonal diversity after ∼70 y, in agreement with empirical data. A mathematical analysis predicts that, without an increase in the naive T cell proliferation rate, this decline will occur >50 yr later than empirically observed. These results are consistent with a model in which exhaustion of the proliferative capacity of naive T cells causes a sharp decline of their effective clonal diversity and imply that therapeutic potentiation of thymopoiesis might either prevent or reverse this outcome. Copyright © 2016 by The American Association of Immunologists, Inc.

  4. Acute and chronic effects of exposure to a 1-mT magnetic field on the cytoskeleton, stress proteins, and proliferation of astroglial cells in culture

    International Nuclear Information System (INIS)

    Bodega, G.; Forcada, I.; Suarez, I.; Fernandez, B.

    2005-01-01

    This paper reports the effects of exposure to static, sinusoidal (50 Hz), and combined static/sinusoidal magnetic fields on cultured astroglial cells. Confluent primary cultures of astroglial cells were exposed to a 1-mT sinusoidal, static, or combined magnetic field for 1 h. In another experiment, cells were exposed to the combined magnetic field for 1, 2, and 4 h. The hsp25, hsp60, hsp70, actin, and glial fibrillary acidic protein contents of the astroglial cells were determined by immunoblotting 24 h after exposure. No significant differences were seen between control and exposed cells with respect to their contents of these proteins, neither were any changes in cell morphology observed. In a third experiment to determine the effect of a chronic (11-day) exposure to a combined 1-mT static/sinusoidal magnetic field on the proliferation of cultured astroglial cells, no significant differences were seen between control, sham-exposed, or exposed cells. These results suggest that exposure to 1-mT sinusoidal, static, or combined magnetic fields has no significant effects on the stress, cytoskeletal protein levels in, or proliferation of cultured astroglial cells

  5. Impaired liver regeneration is associated with reduced cyclin B1 in natural killer T cell-deficient mice.

    Science.gov (United States)

    Ben Ya'acov, Ami; Meir, Hadar; Zolotaryova, Lydia; Ilan, Yaron; Shteyer, Eyal

    2017-03-23

    It has been shown that the proportion of natural killer T cells is markedly elevated during liver regeneration and their activation under different conditions can modulate this process. As natural killer T cells and liver injury are central in liver regeneration, elucidating their role is important. The aim of the current study is to explore the role of natural killer T cells in impaired liver regeneration. Concanvalin A was injected 4 days before partial hepatectomy to natural killer T cells- deficient mice or to anti CD1d1-treated mice. Ki-67 and proliferating cell nuclear antigen were used to measure hepatocytes proliferation. Expression of hepatic cyclin B1 and proliferating cell nuclear antigen were evaluated by Western Blot and liver injury was assessed by ALT and histology. Natural killer T cells- deficient or mice injected with anti CD1d antibodies exhibited reduced liver regeneration. These mice were considerably resistant to ConA-induced liver injury. In the absence of NKT cells hepatic proliferating cell nuclear antigen and cyclin B1 decreased in mice injected with Concanvalin A before partial hepatectomy. This was accompanied with reduced serum interleukin-6 levels. Natural killer T cells play an important role in liver regeneration, which is associated with cyclin B1 and interleukin-6.

  6. Angiopoietin 2 stimulates TIE2-expressing monocytes to suppress T cell activation and to promote regulatory T cell expansion.

    Science.gov (United States)

    Coffelt, Seth B; Chen, Yung-Yi; Muthana, Munitta; Welford, Abigail F; Tal, Andrea O; Scholz, Alexander; Plate, Karl H; Reiss, Yvonne; Murdoch, Craig; De Palma, Michele; Lewis, Claire E

    2011-04-01

    Angiopoietin 2 (ANGPT2) is a proangiogenic cytokine whose expression is often upregulated by endothelial cells in tumors. Expression of its receptor, TIE2, defines a highly proangiogenic subpopulation of myeloid cells in circulation and tumors called TIE2-expressing monocytes/macrophages (TEMs). Genetic depletion of TEMs markedly reduces tumor angiogenesis in various tumor models, emphasizing their essential role in driving tumor progression. Previously, we demonstrated that ANGPT2 augments the expression of various proangiogenic genes, the potent immunosuppressive cytokine, IL-10, and a chemokine for regulatory T cells (Tregs), CCL17 by TEMs in vitro. We now show that TEMs also express higher levels of IL-10 than TIE2(-) macrophages in tumors and that ANGPT2-stimulated release of IL-10 by TEMs suppresses T cell proliferation, increases the ratio of CD4(+) T cells to CD8(+) T cells, and promotes the expansion of CD4(+)CD25(high)FOXP3(+) Tregs. Furthermore, syngeneic murine tumors expressing high levels of ANGPT2 contained not only high numbers of TEMs but also increased numbers of Tregs, whereas genetic depletion of tumor TEMs resulted in a marked reduction in the frequency of Tregs in tumors. Taken together, our data suggest that ANGPT2-stimulated TEMs represent a novel, potent immunosuppressive force in tumors.

  7. T cell resistance to activation by dendritic cells requires long-term culture in simulated microgravity.

    Science.gov (United States)

    Bradley, Jillian H; Stein, Rachel; Randolph, Brad; Molina, Emily; Arnold, Jennifer P; Gregg, Randal K

    2017-11-01

    Immune impairment mediated by microgravity threatens the success of space exploration requiring long-duration spaceflight. The cells of most concern, T lymphocytes, coordinate the host response against microbial and cancerous challenges leading to elimination and long-term protection. T cells are activated upon recognition of specific microbial peptides bound on the surface of antigen presenting cells, such as dendritic cells (DC). Subsequently, this engagement results in T cell proliferation and differentiation into effector T cells driven by autocrine interleukin-2 (IL-2) and other cytokines. Finally, the effector T cells acquire the weaponry needed to destroy microbial invaders and tumors. Studies conducted on T cells during spaceflight, or using Earth-based culture systems, have shown reduced production of cytokines, proliferation and effector functions as compared to controls. This may account for the cases of viral reactivation events and opportunistic infections associated with astronauts of numerous missions. This work has largely been based upon the outcome of T cell activation by stimulatory factors that target select T cell signaling pathways rather than the complex, signaling events related to the natural process of antigen presentation by DC. This study tested the response of an ovalbumin peptide-specific T cell line, OT-II TCH, to activation by DC when the T cells were cultured 24-120 h in a simulated microgravity (SMG) environment generated by a rotary cell culture system. Following 72 h culture of T cells in SMG (SMG-T) or control static (Static-T) conditions, IL-2 production by the T cells was reduced in SMG-T cells compared to Static-T cells upon stimulation by phorbol 12-myristate 13-acetate (PMA) and ionomycin. However, when the SMG-T cells were stimulated with DC and peptide, IL-2 was significantly increased compared to Static-T cells. Such enhanced IL-2 production by SMG-T cells peaked at 72 h SMG culture time and decreased thereafter

  8. Engineering CAR-T cells.

    Science.gov (United States)

    Zhang, Cheng; Liu, Jun; Zhong, Jiang F; Zhang, Xi

    2017-01-01

    Chimeric antigen receptor redirected T cells (CAR-T cells) have achieved inspiring outcomes in patients with B cell malignancies, and are now being investigated in other hematologic malignancies and solid tumors. CAR-T cells are generated by the T cells from patients' or donors' blood. After the T cells are expanded and genetically modified, they are reinfused into the patients. However, many challenges still need to be resolved in order for this technology to gain widespread adoption. In this review, we first discuss the structure and evolution of chimeric antigen receptors. We then report on the tools used for production of CAR-T cells. Finally, we address the challenges posed by CAR-T cells.

  9. Inhibition of Allograft Inflammatory Factor-1 in Dendritic Cells Restrains CD4+ T Cell Effector Responses and Induces CD25+Foxp3+ T Regulatory Subsets

    Directory of Open Access Journals (Sweden)

    Diana M. Elizondo

    2017-11-01

    Full Text Available Allograft inflammatory factor-1 (AIF1 is a cytoplasmic scaffold protein shown to influence immune responses in macrophages and microglial cells. The protein contains Ca2+ binding EF-hand and PDZ interaction domains important for mediating intracellular signaling complexes. This study now reports that AIF1 is expressed in CD11c+ dendritic cells (DC and silencing of expression restrains induction of antigen-specific CD4+ T cell effector responses. AIF1 knockdown in murine DC resulted in impaired T cell proliferation and skewed polarization away from T helper type 1 and 17 fates. In turn, there was a parallel expansion of IL-10-producing and CD25+Foxp3+ T regulatory subsets. These studies are the first to demonstrate that AIF1 expression in DC serves as a potent governor of cognate T cell responses and presents a novel target for engineering tolerogenic DC-based immunotherapies.

  10. Downregulation of proapoptotic Bim augments IL-2-independent T-cell transformation by human T-cell leukemia virus type-1 Tax

    International Nuclear Information System (INIS)

    Higuchi, Masaya; Takahashi, Masahiko; Tanaka, Yuetsu; Fujii, Masahiro

    2014-01-01

    Human T-cell leukemia virus type 1 (HTLV-1), an etiological agent of adult T-cell leukemia, immortalizes and transforms primary human T cells in vitro in both an interleukin (IL)-2-dependent and IL-2-independent manner. Expression of the HTLV-1 oncoprotein Tax transforms the growth of the mouse T-cell line CTLL-2 from being IL-2-dependent to IL-2-independent. Withdrawal of IL-2 from normal activated T cells induces apoptosis, which is mediated through the inducible expression of several proapoptotic proteins, including Bim. In this study, we found that Tax protects IL-2-depleted T cells against Bim-induced apoptosis. Withdrawal of IL-2 from CTLL-2 cells induced a prominent increase in the level of Bim protein in CTLL-2 cells, but not in Tax-transformed CTLL-2 cells. This inhibition of Bim in Tax-transformed CTLL-2 cells was mediated by two mechanisms: downregulation of Bim mRNA and posttranscriptional reduction of Bim protein. Transient expression of Tax in CTLL-2 cells also inhibited IL-2 depletion–induced expression of Bim, however, this decrease in Bim protein expression was not due to downregulation of Bim mRNA, thus indicating that Bim mRNA downregulation in Tax-transformed CTLL-2 occurs only after long-term expression of Tax. Transient expression of Tax in CTLL-2 cells also induced Erk activation, however, this was not involved in the reduction of Bim protein. Knockdown of Bim expression in CTLL-2 cells augmented Tax-induced IL-2-independent transformation. HTLV-1 infection of human T cells also reduced their levels of Bim protein, and restoring Bim expression in HTLV-1-infected cells reduced their proliferation by inducing apoptosis. Taken together, these results indicate that Tax-induced downregulation of Bim in HTLV-1-infected T cells promotes their IL-2-independent growth, thereby supporting the persistence of HTLV-1 infection in vivo

  11. Downregulation of proapoptotic Bim augments IL-2-independent T-cell transformation by human T-cell leukemia virus type-1 Tax.

    Science.gov (United States)

    Higuchi, Masaya; Takahashi, Masahiko; Tanaka, Yuetsu; Fujii, Masahiro

    2014-12-01

    Human T-cell leukemia virus type 1 (HTLV-1), an etiological agent of adult T-cell leukemia, immortalizes and transforms primary human T cells in vitro in both an interleukin (IL)-2-dependent and IL-2-independent manner. Expression of the HTLV-1 oncoprotein Tax transforms the growth of the mouse T-cell line CTLL-2 from being IL-2-dependent to IL-2-independent. Withdrawal of IL-2 from normal activated T cells induces apoptosis, which is mediated through the inducible expression of several proapoptotic proteins, including Bim. In this study, we found that Tax protects IL-2-depleted T cells against Bim-induced apoptosis. Withdrawal of IL-2 from CTLL-2 cells induced a prominent increase in the level of Bim protein in CTLL-2 cells, but not in Tax-transformed CTLL-2 cells. This inhibition of Bim in Tax-transformed CTLL-2 cells was mediated by two mechanisms: downregulation of Bim mRNA and posttranscriptional reduction of Bim protein. Transient expression of Tax in CTLL-2 cells also inhibited IL-2 depletion-induced expression of Bim, however, this decrease in Bim protein expression was not due to downregulation of Bim mRNA, thus indicating that Bim mRNA downregulation in Tax-transformed CTLL-2 occurs only after long-term expression of Tax. Transient expression of Tax in CTLL-2 cells also induced Erk activation, however, this was not involved in the reduction of Bim protein. Knockdown of Bim expression in CTLL-2 cells augmented Tax-induced IL-2-independent transformation. HTLV-1 infection of human T cells also reduced their levels of Bim protein, and restoring Bim expression in HTLV-1-infected cells reduced their proliferation by inducing apoptosis. Taken together, these results indicate that Tax-induced downregulation of Bim in HTLV-1-infected T cells promotes their IL-2-independent growth, thereby supporting the persistence of HTLV-1 infection in vivo. © 2014 The Authors. Cancer Medicine published by John Wiley & Sons Ltd.

  12. Immune regulation in Chandipura virus infection: characterization of CD4+ T regulatory cells from infected mice

    Directory of Open Access Journals (Sweden)

    Shahir Prajakta

    2011-05-01

    Full Text Available Abstract Back ground Chandipura virus produces acute infection in mice. During infection drastic reduction of CD4+, CD8+ and CD19 + cell was noticed. Depletion of lymphocytes also noticed in spleen. The reduction may be due to the regulatory mechanism of immune system to prevent the bystander host tissue injury. There are several mechanisms like generation of regulatory cells, activation induced cell death (ACID etc were indicated to control the activation and maintain cellular homeostasis. Role of regulatory cells in homeostasis has been described in several viral diseases. This study was undertaken to characterize CD4+T regulatory cells from the infected mice. Method In this study we purified the CD4+ T cells from Chandipura virus infected susceptible Balb/c mice. CD4+ T regulatory cells were identified by expression of cell surface markers CD25, CD127 and CTLA-4 and intracellular markers Foxp3, IL-10 and TGF-beta. Antigen specificity and ability to suppress the proliferation of other lymphocytes were studied in vitro by purified CD4+CD25+T regulatory cells from infected mice. The proliferation was calculated by proliferation module of Flow Jo software. Expression of death receptors on regulatory cells were studied by flowcytometer. Results The CD4+ T cells isolated from infected mice expressed characteristic markers of regulatory phenotype at all post infective hours tested. The CD4+ T regulatory cells were proliferated when stimulated with Chandipura virus antigen. The regulatory cells did not suppress the proliferation of splenocytes stimulated with anti CD3 antibody when co cultured with them. Interesting observation was, while purification of CD4+ T cells by negative selection, the population of cells negative for CD4 also co purified along with CD4+ T cell. Flow cytometry analysis and light microscopy revealed that CD4 negative cells were of different size and shape (atypical compared to the normal lymphocytes. Greater percentage of

  13. Effector CD4+ T cells recognize intravascular antigen presented by patrolling monocytes.

    Science.gov (United States)

    Westhorpe, Clare L V; Norman, M Ursula; Hall, Pam; Snelgrove, Sarah L; Finsterbusch, Michaela; Li, Anqi; Lo, Camden; Tan, Zhe Hao; Li, Songhui; Nilsson, Susan K; Kitching, A Richard; Hickey, Michael J

    2018-02-21

    Although effector CD4 + T cells readily respond to antigen outside the vasculature, how they respond to intravascular antigens is unknown. Here we show the process of intravascular antigen recognition using intravital multiphoton microscopy of glomeruli. CD4 + T cells undergo intravascular migration within uninflamed glomeruli. Similarly, while MHCII is not expressed by intrinsic glomerular cells, intravascular MHCII-expressing immune cells patrol glomerular capillaries, interacting with CD4 + T cells. Following intravascular deposition of antigen in glomeruli, effector CD4 + T-cell responses, including NFAT1 nuclear translocation and decreased migration, are consistent with antigen recognition. Of the MHCII + immune cells adherent in glomerular capillaries, only monocytes are retained for prolonged durations. These cells can also induce T-cell proliferation in vitro. Moreover, monocyte depletion reduces CD4 + T-cell-dependent glomerular inflammation. These findings indicate that MHCII + monocytes patrolling the glomerular microvasculature can present intravascular antigen to CD4 + T cells within glomerular capillaries, leading to antigen-dependent inflammation.

  14. Characterization of γδ regulatory T cells from peripheral blood in patients with multiple myeloma

    International Nuclear Information System (INIS)

    Ma, Yongyong; Lei, Huyi; Tan, Jie; Xuan, Li; Wu, Xiuli; Liu, Qifa

    2016-01-01

    γδ regulatory T cells are able to inhibit the activation and function of T cells involved in antigen-specific immune responses. This study aimed to investigate the potential role of γδ regulatory T cells in inhibiting anti-tumor immune responses in patients diagnosed as multiple myeloma (MM). We measured the levels of γδ T cells, the distribution and clonally amplified TCR Vγ and VδT cells in peripheral blood of healthy donors, patients recently diagnosed with MM, and MM patients in remission cohorts. In addition, we evaluated the ability of γδ regulatory T cells to inhibit the proliferation of CD4+CD25- T cells and detected the expression of immunoregulatory-associated molecules. We found that the levels of γδ regulatory T cells from the peripheral blood in patients of MM were significantly higher than those in healthy donors. Comparison of γδT regulatory cells function in MM and healthy donors showed similarly inhibitory effects on the proliferation of T cells. Additionally, TLR8 expression level increased significantly in MM patients compared to healthy donors, while the expression levels of Foxp3, CD25, CTLA4, GITR, GATA3 and Tbet in MM patients and healthy donors showed no significant difference. Taken together, our study reveals the potential role of γδ regulatory T cells in inhibiting anti-tumor immune responses in MM patients.

  15. CD19-Targeted CAR T Cells as Novel Cancer Immunotherapy for Relapsed or Refractory B-Cell Acute Lymphoblastic Leukemia

    OpenAIRE

    Davila, Marco L.; Brentjens, Renier J.

    2016-01-01

    Immunotherapy has demonstrated significant potential for the treatment of patients with chemotherapy-resistant hematologic malignancies and solid tumors. One type of immunotherapy involves the adoptive transfer of T cells that have been genetically modified with a chimeric antigen receptor (CAR) to target a tumor. These hybrid proteins are composed of the antigen-binding domains of an antibody fused to T-cell receptor signaling machinery. CAR T cells that target CD19 recently have made the ju...

  16. Antigen Requirements for Efficient Priming of CD8+ T Cells by Leishmania major-Infected Dendritic Cells

    Science.gov (United States)

    Bertholet, Sylvie; Debrabant, Alain; Afrin, Farhat; Caler, Elisabeth; Mendez, Susana; Tabbara, Khaled S.; Belkaid, Yasmine; Sacks, David L.

    2005-01-01

    CD4+ and CD8+ T-cell responses have been shown to be critical for the development and maintenance of acquired resistance to infections with the protozoan parasite Leishmania major. Monitoring the development of immunodominant or clonally restricted T-cell subsets in response to infection has been difficult, however, due to the paucity of known epitopes. We have analyzed the potential of L. major transgenic parasites, expressing the model antigen ovalbumin (OVA), to be presented by antigen-presenting cells to OVA-specific OT-II CD4+ or OT-I CD8+ T cells. Truncated OVA was expressed in L. major as part of a secreted or nonsecreted chimeric protein with L. donovani 3′ nucleotidase (NT-OVA). Dendritic cells (DC) but not macrophages infected with L. major that secreted NT-OVA could prime OT-I T cells to proliferate and release gamma interferon. A diminished T-cell response was observed when DC were infected with parasites expressing nonsecreted NT-OVA or with heat-killed parasites. Inoculation of mice with transgenic parasites elicited the proliferation of adoptively transferred OT-I T cells and their recruitment to the site of infection in the skin. Together, these results demonstrate the possibility of targeting heterologous antigens to specific cellular compartments in L. major and suggest that proteins secreted or released by L. major in infected DC are a major source of peptides for the generation of parasite-specific CD8+ T cells. The ability of L. major transgenic parasites to activate OT-I CD8+ T cells in vivo will permit the analysis of parasite-driven T-cell expansion, differentiation, and recruitment at the clonal level. PMID:16177338

  17. Human xenospecific T suppressor cells inhibit T helper cell proliferation to porcine aortic endothelial cells, and NF-kappaB activity in porcine APC.

    Science.gov (United States)

    Ciubotariu, R; Li, J; Colovai, A I; Platt, J L; Cortesini, R; Suciu Foca Cortesini, N

    2001-05-01

    Human T suppressor cells (Ts), capable of preventing autologous T helper cells (Th) from reacting against xenogeneic pig endothelial cells and pig APC can be generated in vitro. Ts derive from a population of CD3(+)CD8(+)CD28(-) T lymphocytes and specifically recognize the MHC class I antigens of the APC used for in vitro immunization. To study the mechanism that underlies suppression, we investigated whether Ts inhibit the expression of costimulatory molecules in xenogeneic professional and semiprofessional APC. We found that Ts down-regulate Th-induced expression of CD86 in pig APC, and that this effect occurs at the level of transcription, as indicated by nuclear run-on and Northern blot assays. EMSA results revealed that inhibition of CD86 expression is mediated by inactivation of transcription factor NF-kappaB. Furthermore, transfection of pig APC with a vector expressing NF-kappaB p65 partially rescued Th-induced expression of the CD86 molecule. These results strongly support the concept that xenospecific Ts inhibit the APC function of xenogeneic cells by preventing activation of NF-kappaB.

  18. Tumor cells and memory T cells converge at glycolysis

    Science.gov (United States)

    Karthikeyan, Swathi; Geschwind, Jean-Francois; Ganapathy-Kanniappan, Shanmugasundaram

    2014-01-01

    In the immune system, activation of naïve T (Tn) cells into effector T cells (Teff) involves a metabolic switch to glycolysis to promote rapid proliferation and differentiation. In the October issue of The Journal of Clinical Investigation, Sukumar et al. have demonstrated that in CD8+ memory T (Tems) cells glycolytic phenotype contributes to the shortened lifespan of Tems. Conversely, inhibition of glycolysis in Tems not only extended their viability but also augmented desirable properties. Notably, they also demonstrate that glycolytic inhibition during the ex vivo clonal expansion of tumor-specific Tems enhanced their antitumor function. Overall, the data suggest that an antiglycolytic strategy targeting the Tems could enhance antitumor immune response. On the other hand, cancer cells have long been known to exhibit metabolic reprogramming which involves a shift toward glycolysis (the conversion of glucose into lactate) to facilitate uninterrupted growth. Interestingly, antiglycolytic treatment of cancer cells has been known to trigger antitumor immune response as well. Taken together, it is probable that a strategy involving concurrent inhibition of glycolysis in tumor cells and Tems could promote a dual attack on cancer by inducing an effective antitumor immune response and an immunogenic chemotherapy. PMID:24556820

  19. Tolerance without clonal expansion: self-antigen-expressing B cells program self-reactive T cells for future deletion.

    Science.gov (United States)

    Frommer, Friederike; Heinen, Tobias J A J; Wunderlich, F Thomas; Yogev, Nir; Buch, Thorsten; Roers, Axel; Bettelli, Estelle; Müller, Werner; Anderton, Stephen M; Waisman, Ari

    2008-10-15

    B cells have been shown in various animal models to induce immunological tolerance leading to reduced immune responses and protection from autoimmunity. We show that interaction of B cells with naive T cells results in T cell triggering accompanied by the expression of negative costimulatory molecules such as PD-1, CTLA-4, B and T lymphocyte attenuator, and CD5. Following interaction with B cells, T cells were not induced to proliferate, in a process that was dependent on their expression of PD-1 and CTLA-4, but not CD5. In contrast, the T cells became sensitive to Ag-induced cell death. Our results demonstrate that B cells participate in the homeostasis of the immune system by ablation of conventional self-reactive T cells.

  20. Highly-Immunogenic Virally-Vectored T-cell Vaccines Cannot Overcome Subversion of the T-cell Response by HCV during Chronic Infection

    Directory of Open Access Journals (Sweden)

    Leo Swadling

    2016-08-01

    Full Text Available An effective therapeutic vaccine for the treatment of chronic hepatitis C virus (HCV infection, as an adjunct to newly developed directly-acting antivirals (DAA, or for the prevention of reinfection, would significantly reduce the global burden of disease associated with chronic HCV infection. A recombinant chimpanzee adenoviral (ChAd3 vector and a modified vaccinia Ankara (MVA, encoding the non-structural proteins of HCV (NSmut, used in a heterologous prime/boost regimen induced multi-specific, high-magnitude, durable HCV-specific CD4+ and CD8+ T-cell responses in healthy volunteers, and was more immunogenic than a heterologous Ad regimen. We now assess the immunogenicity of this vaccine regimen in HCV infected patients (including patients with a low viral load suppressed with interferon/ribavirin therapy, determine T-cell cross-reactivity to endogenous virus, and compare immunogenicity with that observed previously in both healthy volunteers and in HCV infected patients vaccinated with the heterologous Ad regimen. Vaccination of HCV infected patients with ChAd3-NSmut/MVA-NSmut was well tolerated. Vaccine-induced HCV-specific T-cell responses were detected in 8/12 patients; however, CD4+ T-cell responses were rarely detected, and the overall magnitude of HCV-specific T-cell responses was markedly reduced when compared to vaccinated healthy volunteers. Furthermore, HCV-specific cells had a distinct partially-functional phenotype (lower expression of activation markers, granzyme B, and TNFα production, weaker in vitro proliferation, and higher Tim3 expression, with comparable Tbet and Eomes expression compared to healthy volunteers. Robust anti-vector T-cells and antibodies were induced, showing that there is no global defect in immunity. The level of viremia at the time of vaccination did not correlate with the magnitude of the vaccine-induced T-cell response. Full-length, next-generation sequencing of the circulating virus demonstrated that T-cells

  1. An analytical biomarker for treatment of patients with recurrent B-ALL after remission induced by infusion of anti-CD19 chimeric antigen receptor T (CAR-T) cells.

    Science.gov (United States)

    Zhang, Yajing; Zhang, Wenying; Dai, Hanren; Wang, Yao; Shi, Fengxia; Wang, Chunmeng; Guo, Yelei; Liu, Yang; Chen, Meixia; Feng, Kaichao; Zhang, Yan; Liu, Chuanjie; Yang, Qingming; Li, Suxia; Han, Weidong

    2016-04-01

    Anti-CD19 chimeric antigen receptor-modified T (CAR-T-19) cells have emerged as a powerful targeted immunotherapy for B-cell lineage acute lymphoblastic leukemia with a remarkable clinical response in recent trials. Nonetheless, few data are available on the subsequent clinical monitoring and treatment of the patients, especially those with disease recurrence after CAR-T-19 cell infusion. Here, we analyzed three patients who survived after our phase I clinical trial and who were studied by means of biomarkers reflecting persistence of CAR-T-19 cells in vivo and predictive factors directing further treatment. One patient achieved 9-week sustained complete remission and subsequently received an allogeneic hematopoietic stem cell transplant. Another patient who showed relapse after 20 weeks without detectable leukemia in the cerebrospinal fluid after CAR-T-19 cell treatment was able to achieve a morphological remission under the influence of stand-alone low-dose chemotherapeutic agents. The third patient gradually developed extensive extramedullary involvement in tissues with scarce immune- cell infiltration during a long period of hematopoietic remission after CAR-T-19 cell therapy. Long-term and discontinuous increases in serum cytokines (mainly interleukin 6 and C-reactive protein) were identified in two patients (Nos. 1 and 6) even though only a low copy number of CAR molecules could be detected in their peripheral blood. This finding was suggestive of persistent functional activity of CAR-T-19 cells. Combined analyses of laboratory biomarkers with their clinical manifestations before and after salvage treatment showed that the persistent immunosurveillance mediated by CAR-T-19 cells would inevitably potentiate the leukemia-killing effectiveness of subsequent chemotherapy in patients who showed relapse after CAR-T-19-induced remission.

  2. Mind bomb-1 in dendritic cells is specifically required for Notch-mediated T helper type 2 differentiation.

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    Hyun-Woo Jeong

    Full Text Available In dendritic cell (DC-CD4(+ T cell interaction, Notch signaling has been implicated in the CD4(+ T cell activation, proliferation, and subset differentiation. However, there has been a lot of debate on the exact role of Notch signaling. Here, we observed that expression of Mind bomb-1 (Mib1, a critical regulator of Notch ligands for the activation of Notch signaling, increases gradually as precursor cells differentiate into DCs in mice. To clarify the role of Mib1 in DC-CD4(+ T cell interactions, we generated Mib1-null bone marrow-derived DCs. These cells readily expressed Notch ligands but failed to initiate Notch activation in the adjacent cells. Nevertheless, Mib1-null DCs were able to prime the activation and proliferation of CD4(+ T cells, suggesting that Notch activation in CD4(+ T cells is not required for these processes. Intriguingly, stimulation of CD4(+ T cells with Mib1-null DCs resulted in dramatically diminished Th2 cell populations, while preserving Th1 cell populations, both in vitro and in vivo. Our results demonstrate that Mib1 in DCs is critical for the activation of Notch signaling in CD4(+ T cells, and Notch signaling reinforces Th2 differentiation, but is not required for the activation or proliferation of the CD4(+ T cells.

  3. Involvement of IRF4 dependent dendritic cells in T cell dependent colitis

    DEFF Research Database (Denmark)

    Pool, Lieneke; Rivollier, Aymeric Marie Christian; Agace, William Winston

    in genetically susceptible individuals and pathogenic CD4+ T cells, which accumulate in the inflamed mucosa, are believed to be key drivers of the disease. While dendritic cells (DCs) are important in the priming of intestinal adaptive immunity and tolerance their role in the initiation and perpetuation...... of chronic intestinal inflammation remains unclear. In the current study we used the CD45RBhi T cell transfer model of colitis to determine the role of IRF4 dependent DCs in intestinal inflammation. In this model naïve CD4+ T cells when transferred into RAG-/- mice, proliferate and expand in response...... to bacterial derived luminal antigen, localize to the intestinal mucosa and induce colitis. Adoptive transfer of naïve T cells into CD11cCre.IRF4fl/fl.RAG-1-/- mice resulted in reduced monocyte recruitment to the intestine and mesenteric lymph nodes (MLN) compared to Cre- controls. Inflammatory cytokines...

  4. High levels of the type III inorganic phosphate transporter PiT1 (SLC20A1) can confer faster cell adhesion

    DEFF Research Database (Denmark)

    Kongsfelt, Iben Boutrup; Byskov, Kristina; Pedersen, Lasse Ebdrup

    2014-01-01

    overexpression led to faster cell spreading. The final total numbers of attached cells did, however, not differ between cultures of PiT1 overexpressing cells and control cells of neither cell type. We suggest that the PiT1-mediated fast adhesion potentials allow the cells to go faster out of G0/G1 and thereby......The inorganic phosphate transporter PiT1 (SLC20A1) is ubiquitously expressed in mammalian cells. We recently showed that overexpression of human PiT1 was sufficient to increase proliferation of two strict density-inhibited cell lines, murine fibroblastic NIH3T3 and pre-osteoblastic MC3T3-E1 cells......, and allowed the cultures to grow to higher cell densities. In addition, upon transformation NIH3T3 cells showed increased ability to form colonies in soft agar. The cellular regulation of PiT1 expression supports that cells utilize the PiT1 levels to control proliferation, with non-proliferating cells showing...

  5. Pharmacologic suppression of target cell recognition by engineered T cells expressing chimeric T-cell receptors.

    Science.gov (United States)

    Alvarez-Vallina, L; Yañez, R; Blanco, B; Gil, M; Russell, S J

    2000-04-01

    Adoptive therapy with autologous T cells expressing chimeric T-cell receptors (chTCRs) is of potential interest for the treatment of malignancy. To limit possible T-cell-mediated damage to normal tissues that weakly express the targeted tumor antigen (Ag), we have tested a strategy for the suppression of target cell recognition by engineered T cells. Jurkat T cells were transduced with an anti-hapten chTCR tinder the control of a tetracycline-suppressible promoter and were shown to respond to Ag-positive (hapten-coated) but not to Ag-negative target cells. The engineered T cells were then reacted with hapten-coated target cells at different effector to target cell ratios before and after exposure to tetracycline. When the engineered T cells were treated with tetracycline, expression of the chTCR was greatly decreased and recognition of the hapten-coated target cells was completely suppressed. Tetracycline-mediated suppression of target cell recognition by engineered T cells may be a useful strategy to limit the toxicity of the approach to cancer gene therapy.

  6. CD4~+Foxp3~+ regulatory T cells converted by rapamycin from peripheral CD4~+ CD25~-naive T cells display more potent regulatory ability in vitro

    Institute of Scientific and Technical Information of China (English)

    CHEN Jian-fei; GAO Jie; ZHANG Dong; WANG Zi-han; ZHU Ji-ye

    2010-01-01

    Background Rapamycin (RAPA) is a relatively new immunosuppressant drug that functions as a serine/threonine kinase inhibitor to prevent rejection in organ transplantation. RAPA blocks activation of T-effector (Teff) cells by inhibiting the response to interleukin-2. Recently, RAPA was also shown to selectively expand the T-regulator (Treg) cell population. To date, no studies have examined the mechanism by which RAPA converts Teff cells to Treg cells. Methods Peripheral CD4~+CD25~- naive T cells were cultivated with RAPA and B cells as antigen-presenting cells (APCs) in vitro. CD4~+CD25~- T cells were harvested after 6 days and analyzed for expression of forkhead box protein 3 (Foxp3) using flow cytometry. CD4~+CD25~+CD127~- subsets as the converted Tregs were isolated from the mixed lymphocyte reactions (MLR) with CD127 negative selection, followed by CD4 and CD25 positive selection using microbeads and magnetic separation column (MSC). Moreover, mRNA was extracted from converted Tregs and C57BL/6 naive CD4~+CD25~+ T cells and Foxp3 levels were examined by quantitative real-time polymerase chain reaction (rt-PCR). A total of 1×10~5 carboxyfluorescein succinimidyl ester (CFSE)-labeled naive CD4~+CD25~- T cells/well from C57BL/6 mice were cocultured with DBA/2 or C3H maturation of dendritic cells (mDCs) (0.25×10~5/well) in 96-well round-bottom plates for 6 days. Then 1×10~5 or 0.25×10~5 converted Treg cells were added to every well as regulatory cells. Cells were harvested after 6 days of culture and analyzed for proliferation of CFSE-labeled naive CD4~+CD25~- T cells using flow cytometry. Data were analyzed using CellQuest software.Results We found that RAPA can convert peripheral CD4~+CD25~- naive T Cells to CD4~+Foxp3~+ Treg cells using B cells as APCs, and this subtype of Treg can potently suppress Teff proliferation and maintain antigenic specificity. Conclusion Our findings provide evidence that RAPA induces Treg cell conversion from Teff cells and

  7. Immunomodulatory effect of tea saponin in immune T-cells and T-lymphoma cells via regulation of Th1, Th2 immune response and MAPK/ERK2 signaling pathway.

    Science.gov (United States)

    Bhardwaj, Jyoti; Chaudhary, Narendra; Seo, Hyo-Jin; Kim, Min-Yong; Shin, Tai-Sun; Kim, Jong-Deog

    2014-06-01

    The anti-cancer activity of saponins and phenolic compounds present in green tea was previously reported. However, the immunomodulatory and adjuvanticity activity of tea saponin has never been studied. In this study, we investigated the immunomodulatory effect of tea saponin in T-lymphocytes and EL4 cells via regulation of cytokine response and mitogen-activated protein kinases (MAPK) signaling pathway. Quantitative analysis of mRNA expression level of cytokines were performed by reverse transcription polymerase chain reaction following stimulation with tea saponin, ovalbumin (OVA) alone or tea saponin in combination with OVA. Tea saponin inhibited the proliferation of EL4 cells measured in a dose-dependent manner. No cytotoxicity effect of tea saponin was detected in T-lymphocytes; rather, tea saponin enhanced the proliferation of T-lymphocytes. Tea saponin with OVA increased the expression of interleukin (IL)-1, IL-2, IL-12, interferon-γ and tumor necrosis factor (TNF)-α and decreased the expression level of IL-10 and IL-8 in T-lymphocytes. Furthermore, tea saponin, in the presence of OVA, downregulated the MAPK signaling pathway via inhibition of IL-4, IL-8 and nuclear factor kappaB (NF-κB) in EL4 cells. Th1 cytokines enhancer and Th2 cytokines and NF-κB inhibitor, tea saponin can markedly inhibit the proliferation and invasiveness of T-lymphoma (EL4) cells, possibly due to TNF-α- and NF-κB-mediated regulation of MAPK signaling pathway.

  8. Sequential activation of CD8+ T cells in the draining lymph nodes in response to pulmonary virus infection.

    Science.gov (United States)

    Yoon, Heesik; Legge, Kevin L; Sung, Sun-sang J; Braciale, Thomas J

    2007-07-01

    We have used a TCR-transgenic CD8+ T cell adoptive transfer model to examine the tempo of T cell activation and proliferation in the draining lymph nodes (DLN) in response to respiratory virus infection. The T cell response in the DLN differed for mice infected with different type A influenza strains with the onset of T cell activation/proliferation to the A/JAPAN virus infection preceding the A/PR8 response by 12-24 h. This difference in T cell activation/proliferation correlated with the tempo of accelerated respiratory DC (RDC) migration from the infected lungs to the DLN in response to influenza virus infection, with the migrant RDC responding to the A/JAPAN infection exhibiting a more rapid accumulation in the lymph nodes (i.e., peak migration for A/JAPAN at 18 h, A/PR8 at 24-36 h). Furthermore, in vivo administration of blocking anti-CD62L Ab at various time points before/after infection revealed that the virus-specific CD8+ T cells entered the DLN and activated in a sequential "conveyor belt"-like fashion. These results indicate that the tempo of CD8+ T cell activation/proliferation after viral infection is dependent on the tempo of RDC migration to the DLN and that T cell activation occurs in an ordered sequential fashion.

  9. DNA segment containing C/sub β1/, a gene for the constant region of the β chain of the T-cell antigen receptor, was inserted into chromosome 6 in cells from one patients with human T-cell leukemia

    International Nuclear Information System (INIS)

    Ino, T.; Kurosawa, Y.; Yoshida, M.C.; Hirano, M.

    1987-01-01

    DNA rearrangements that occurred in the vicinity of T-cell antigen receptor β-chain gene clusters residing on chromosome 7 were examined in human T-cell acute lymphoblastic leukemia cells. In one patient, it was observed that, for the T-cell receptor β-chain genes, a D/sub β 1/-J/sub β2.3/ (where D is diversity and J is joining) junction was found on one chromosome, while the other chromosome kept the germ-line configuration. If this D/sub β/-J/sub β/ junction was formed by the customary deletion mechanism, the C/sub β1/ gene (where C is constant) located between the D/sub β1/ and J/sub Β2.3/ loci should have disappeared from this chromosome. The C/sub β1/ gene indeed was absent from the rearranged chromosome 7, but it was found on chromosome 6 as an inserted segment. The implications of the observations are discussed

  10. Ptpn11 Deletion in CD4+ Cells Does Not Affect T Cell Development and Functions but Causes Cartilage Tumors in a T Cell-Independent Manner

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    S. M. Shahjahan Miah

    2017-10-01

    Full Text Available The ubiquitously expressed tyrosine phosphatase Src homology region 2 domain-containing phosphatase-2 (SHP-2, encoded by Ptpn11 is required for constitutive cellular processes including proliferation, differentiation, and the regulation of immune responses. During development and maturation, subsets of T cells express a variety of inhibitory receptors known to associate with phosphatases, which in turn, dephosphorylate key players of activating receptor signaling pathways. We hypothesized that SHP-2 deletion would have major effects on T cell development by altering the thresholds for activation, as well as positive and negative selection. Surprisingly, using mice conditionally deficient for SHP-2 in the T cell lineage, we show that the development of these lymphocytes is globally intact. In addition, our data demonstrate that SHP-2 absence does not compromise T cell effector functions, suggesting that SHP-2 is dispensable in these cells. Unexpectedly, in aging mice, Ptpn11 gene deletion driven by CD4 Cre recombinase leads to cartilage tumors in wrist bones in a T cell-independent manner. These tumors resemble miniature cartilaginous growth plates and contain CD4-lineage positive chondrocyte-like cells. Altogether these results indicate that SHP-2 is a cartilage tumor suppressor during aging.

  11. Accelerated in vivo proliferation of memory phenotype CD4+ T-cells in human HIV-1 infection irrespective of viral chemokine co-receptor tropism.

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    Yan Zhang

    Full Text Available CD4(+ T-cell loss is the hallmark of HIV-1 infection. CD4 counts fall more rapidly in advanced disease when CCR5-tropic viral strains tend to be replaced by X4-tropic viruses. We hypothesized: (i that the early dominance of CCR5-tropic viruses results from faster turnover rates of CCR5(+ cells, and (ii that X4-tropic strains exert greater pathogenicity by preferentially increasing turnover rates within the CXCR4(+ compartment. To test these hypotheses we measured in vivo turnover rates of CD4(+ T-cell subpopulations sorted by chemokine receptor expression, using in vivo deuterium-glucose labeling. Deuterium enrichment was modeled to derive in vivo proliferation (p and disappearance (d* rates which were related to viral tropism data. 13 healthy controls and 13 treatment-naive HIV-1-infected subjects (CD4 143-569 cells/ul participated. CCR5-expression defined a CD4(+ subpopulation of predominantly CD45R0(+ memory cells with accelerated in vivo proliferation (p = 2.50 vs 1.60%/d, CCR5(+ vs CCR5(-; healthy controls; P<0.01. Conversely, CXCR4 expression defined CD4(+ T-cells (predominantly CD45RA(+ naive cells with low turnover rates. The dominant effect of HIV infection was accelerated turnover of CCR5(+CD45R0(+CD4(+ memory T-cells (p = 5.16 vs 2.50%/d, HIV vs controls; P<0.05, naïve cells being relatively unaffected. Similar patterns were observed whether the dominant circulating HIV-1 strain was R5-tropic (n = 9 or X4-tropic (n = 4. Although numbers were small, X4-tropic viruses did not appear to specifically drive turnover of CXCR4-expressing cells (p = 0.54 vs 0.72 vs 0.44%/d in control, R5-tropic, and X4-tropic groups respectively. Our data are most consistent with models in which CD4(+ T-cell loss is primarily driven by non-specific immune activation.

  12. Meningeal mast cell-T cell crosstalk regulates T cell encephalitogenicity.

    Science.gov (United States)

    Russi, Abigail E; Walker-Caulfield, Margaret E; Guo, Yong; Lucchinetti, Claudia F; Brown, Melissa A

    2016-09-01

    GM-CSF is a cytokine produced by T helper (Th) cells that plays an essential role in orchestrating neuroinflammation in experimental autoimmune encephalomyelitis, a rodent model of multiple sclerosis. Yet where and how Th cells acquire GM-CSF expression is unknown. In this study we identify mast cells in the meninges, tripartite tissues surrounding the brain and spinal cord, as important contributors to antigen-specific Th cell accumulation and GM-CSF expression. In the absence of mast cells, Th cells do not accumulate in the meninges nor produce GM-CSF. Mast cell-T cell co-culture experiments and selective mast cell reconstitution of the meninges of mast cell-deficient mice reveal that resident meningeal mast cells are an early source of caspase-1-dependent IL-1β that licenses Th cells to produce GM-CSF and become encephalitogenic. We also provide evidence of mast cell-T cell co-localization in the meninges and CNS of recently diagnosed acute MS patients indicating similar interactions may occur in human demyelinating disease. Copyright © 2016 Elsevier Ltd. All rights reserved.

  13. Characteristics of CD8+ T cell subsets in Chinese patients with chronic HIV infection during initial ART.

    Science.gov (United States)

    Jiao, Yanmei; Hua, Wei; Zhang, Tong; Zhang, Yonghong; Ji, Yunxia; Zhang, Hongwei; Wu, Hao

    2011-03-25

    CD8+ T cells may play an important role in protecting against HIV. However, the changes of CD8+ T cell subsets during early period of ART have not been fully studied. Twenty-one asymptomatic treatment-naive HIV-infected patients with CD4 T+ cells less than 350 cells/μl were enrolled in the study. Naïve, central memory(CM), effective memory(EM) and terminally differentiated effector (EMRA) CD8+ cell subsets and their activation and proliferation subsets were evaluated in blood samples collected at base line, and week 2, 4, 8 and 12 of ART. The total CD8+ T cells declined and the Naïve and CM subsets had a tendency of increase. Activation levels of all CD8+ T cell subsets except EMRA subset decreased after ART. However, proliferation levels of total CD8+ T cells, EMRA, EM and CM subsets increased at the first 4 weeks of ART, then decreased. Proliferation level of the naïve cells decreased after ART. The changes of CD8+ T cell subsets during initial ART are complex. Our results display a complete phenotypical picture of CD8+ cell subsets during initial ART and provide insights for understanding of immune status during ART.

  14. Characteristics of CD8+ T cell subsets in Chinese patients with chronic HIV infection during initial ART

    Directory of Open Access Journals (Sweden)

    Zhang Hongwei

    2011-03-01

    Full Text Available Abstract Background CD8+ T cells may play an important role in protecting against HIV. However, the changes of CD8+ T cell subsets during early period of ART have not been fully studied. Methods Twenty-one asymptomatic treatment-naive HIV-infected patients with CD4 T+ cells less than 350 cells/μl were enrolled in the study. Naïve, central memory(CM, effective memory(EM and terminally differentiated effector (EMRA CD8+ cell subsets and their activation and proliferation subsets were evaluated in blood samples collected at base line, and week 2, 4, 8 and 12 of ART. Results The total CD8+ T cells declined and the Naïve and CM subsets had a tendency of increase. Activation levels of all CD8+ T cell subsets except EMRA subset decreased after ART. However, proliferation levels of total CD8+ T cells, EMRA, EM and CM subsets increased at the first 4 weeks of ART, then decreased. Proliferation level of the naïve cells decreased after ART. Conclusion The changes of CD8+ T cell subsets during initial ART are complex. Our results display a complete phenotypical picture of CD8+ cell subsets during initial ART and provide insights for understanding of immune status during ART.

  15. Phosphorylation site dynamics of early T-cell receptor signaling

    DEFF Research Database (Denmark)

    Chylek, Lily A; Akimov, Vyacheslav; Dengjel, Jörn

    2014-01-01

    In adaptive immune responses, T-cell receptor (TCR) signaling impacts multiple cellular processes and results in T-cell differentiation, proliferation, and cytokine production. Although individual protein-protein interactions and phosphorylation events have been studied extensively, we lack...... that diverse dynamic patterns emerge within seconds. We detected phosphorylation dynamics as early as 5 s and observed widespread regulation of key TCR signaling proteins by 30 s. Development of a computational model pointed to the presence of novel regulatory mechanisms controlling phosphorylation of sites...... a systems-level understanding of how these components cooperate to control signaling dynamics, especially during the crucial first seconds of stimulation. Here, we used quantitative proteomics to characterize reshaping of the T-cell phosphoproteome in response to TCR/CD28 co-stimulation, and found...

  16. Activated T cells sustain myeloid-derived suppressor cell-mediated immune suppression

    Science.gov (United States)

    Damuzzo, Vera; Francescato, Samuela; Pozzuoli, Assunta; Berizzi, Antonio; Mocellin, Simone; Rossi, Carlo Riccardo; Bronte, Vincenzo; Mandruzzato, Susanna

    2016-01-01

    The expansion of myeloid derived suppressor cells (MDSCs), a suppressive population able to hamper the immune response against cancer, correlates with tumor progression and overall survival in several cancer types. We have previously shown that MDSCs can be induced in vitro from precursors present in the bone marrow and observed that these cells are able to actively proliferate in the presence of activated T cells, whose activation level is critical to drive the suppressive activity of MDSCs. Here we investigated at molecular level the mechanisms involved in the interplay between MDSCs and activated T cells. We found that activated T cells secrete IL-10 following interaction with MDSCs which, in turn, activates STAT3 phosphorylation on MDSCs then leading to B7-H1 expression. We also demonstrated that B7-H1+ MDSCs are responsible for immune suppression through a mechanism involving ARG-1 and IDO expression. Finally, we show that the expression of ligands B7-H1 and MHC class II both on in vitro-induced MDSCs and on MDSCs in the tumor microenvironment of cancer patients is paralleled by an increased expression of their respective receptors PD-1 and LAG-3 on T cells, two inhibitory molecules associated with T cell dysfunction. These findings highlight key molecules and interactions responsible for the extensive cross-talk between MDSCs and activated T cells that are at the basis of immune suppression. PMID:26700461

  17. Chimeric Antigen Receptor T Cell (Car T Cell Therapy In Hematology

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    Pinar Ataca

    2015-12-01

    Full Text Available It is well demonstrated that immune system can control and eliminate cancer cells. Immune-mediated elimination of tumor cells has been discovered and is the basis of both cancer vaccines and cellular therapies including hematopoietic stem cell transplantation (HSCT. Adoptive T cell transfer has been improved to be more specific and potent and cause less off-target toxicities. Currently, there are two forms of engineered T cells being tested in clinical trials: T cell receptor (TCR and chimeric antigen receptor (CAR modified T cells. On July 1, 2014, the United States Food and Drug Administration granted ‘breakthrough therapy’ designation to anti-CD19 CAR T cell therapy. Many studies were conducted to evaluate the beneficiaries of this exciting and potent new treatment modality. This review summarizes the history of adoptive immunotherapy, adoptive immunotherapy using CARs, the CAR manufacturing process, preclinical-clinical studies, effectiveness and drawbacks of this strategy.

  18. CD4+ Primary T Cells Expressing HCV-Core Protein Upregulate Foxp3 and IL-10, Suppressing CD4 and CD8 T Cells

    Science.gov (United States)

    Aguado, Enrique; Garcia-Cozar, Francisco

    2014-01-01

    Adaptive T cell responses are critical for controlling HCV infection. While there is clinical evidence of a relevant role for regulatory T cells in chronic HCV-infected patients, based on their increased number and function; mechanisms underlying such a phenomena are still poorly understood. Accumulating evidence suggests that proteins from Hepatitis C virus can suppress host immune responses. We and others have shown that HCV is present in CD4+ lymphocytes from chronically infected patients and that HCV-core protein induces a state of unresponsiveness in the CD4+ tumor cell line Jurkat. Here we show that CD4+ primary T cells lentivirally transduced with HCV-core, not only acquire an anergic phenotype but also inhibit IL-2 production and proliferation of bystander CD4+ or CD8+ T cells in response to anti-CD3 plus anti-CD28 stimulation. Core-transduced CD4+ T cells show a phenotype characterized by an increased basal secretion of the regulatory cytokine IL-10, a decreased IFN-γ production upon stimulation, as well as expression of regulatory T cell markers, CTLA-4, and Foxp3. A significant induction of CD4+CD25+CD127lowPD-1highTIM-3high regulatory T cells with an exhausted phenotype was also observed. Moreover, CCR7 expression decreased in HCV-core expressing CD4+ T cells explaining their sequestration in inflamed tissues such as the infected liver. This work provides a new perspective on de novo generation of regulatory CD4+ T cells in the periphery, induced by the expression of a single viral protein. PMID:24465502

  19. CD4+ primary T cells expressing HCV-core protein upregulate Foxp3 and IL-10, suppressing CD4 and CD8 T cells.

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    Cecilia Fernandez-Ponce

    Full Text Available Adaptive T cell responses are critical for controlling HCV infection. While there is clinical evidence of a relevant role for regulatory T cells in chronic HCV-infected patients, based on their increased number and function; mechanisms underlying such a phenomena are still poorly understood. Accumulating evidence suggests that proteins from Hepatitis C virus can suppress host immune responses. We and others have shown that HCV is present in CD4+ lymphocytes from chronically infected patients and that HCV-core protein induces a state of unresponsiveness in the CD4+ tumor cell line Jurkat. Here we show that CD4+ primary T cells lentivirally transduced with HCV-core, not only acquire an anergic phenotype but also inhibit IL-2 production and proliferation of bystander CD4+ or CD8+ T cells in response to anti-CD3 plus anti-CD28 stimulation. Core-transduced CD4+ T cells show a phenotype characterized by an increased basal secretion of the regulatory cytokine IL-10, a decreased IFN-γ production upon stimulation, as well as expression of regulatory T cell markers, CTLA-4, and Foxp3. A significant induction of CD4+CD25+CD127(lowPD-1(highTIM-3(high regulatory T cells with an exhausted phenotype was also observed. Moreover, CCR7 expression decreased in HCV-core expressing CD4+ T cells explaining their sequestration in inflamed tissues such as the infected liver. This work provides a new perspective on de novo generation of regulatory CD4+ T cells in the periphery, induced by the expression of a single viral protein.

  20. CD4+ T cell effects on CD8+ T cell location defined using bioluminescence.

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    Mitra Azadniv

    2011-01-01

    Full Text Available T lymphocytes of the CD8+ class are critical in delivering cytotoxic function and in controlling viral and intracellular infections. These cells are "helped" by T lymphocytes of the CD4+ class, which facilitate their activation, clonal expansion, full differentiation and the persistence of memory. In this study we investigated the impact of CD4+ T cells on the location of CD8+ T cells, using antibody-mediated CD4+ T cell depletion and imaging the antigen-driven redistribution of bioluminescent CD8+ T cells in living mice. We documented that CD4+ T cells influence the biodistribution of CD8+ T cells, favoring their localization to abdominal lymph nodes. Flow cytometric analysis revealed that this was associated with an increase in the expression of specific integrins. The presence of CD4+ T cells at the time of initial CD8+ T cell activation also influences their biodistribution in the memory phase. Based on these results, we propose the model that one of the functions of CD4+ T cell "help" is to program the homing potential of CD8+ T cells.

  1. Increasing the safety and efficacy of chimeric antigen receptor T cell therapy

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    Hua Li

    2017-04-01

    Full Text Available Abstract Chimeric antigen receptor (CAR T cell therapy is a promising cancer treatment that has recently been undergoing rapid development. However, there are still some major challenges, including precise tumor targeting to avoid off-target or “on-target/off-tumor” toxicity, adequate T cell infiltration and migration to solid tumors and T cell proliferation and persistence across the physical and biochemical barriers of solid tumors. In this review, we focus on the primary challenges and strategies to design safe and effective CAR T cells, including using novel cutting-edge technologies for CAR and vector designs to increase both the safety and efficacy, further T cell modification to overcome the tumor-associated immune suppression, and using gene editing technologies to generate universal CAR T cells. All these efforts promote the development and evolution of CAR T cell therapy and move toward our ultimate goal—curing cancer with high safety, high efficacy, and low cost.

  2. Effects of nilotinib on regulatory T cells: the dose matters

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    Chen Baoan

    2010-01-01

    Full Text Available Abstract Background Nilotinib is a tyrosine kinase inhibitor with high target specificity. Here, we characterized the effects of nilotinib for the first time on CD4+CD25+ regulatory T cells (Tregs which regulate anti-tumor/leukemia immune responses. Design and Methods Carboxyfluorescein diacetate succinimidyl ester (CFSE and 5-bromo-2-deoxy -uridine (BrdU were used to assess the proliferation and cell cycle distribution of Tregs. The expression of the transcription factor forkhead box P3 (FoxP3 and the glucocorticoid-induced tumor necrosis factor receptor (GITR were measured by flow cytometry. Western blotting analysis was used to detect the effects of nilotinib on the signal transduction cascade of T-cell receptor (TCR in Tregs. Results Nilotinib inhibited the proliferation and suppressive capacity of Tregs in a dose-dependent manner. However, the production of cytokines secreted by Tregs and CD4+CD25- T cells was only inhibited at high concentrations of nilotinib exceeding the mean therapeutic serum concentrations of the drug in patients. Only high doses of nilotinib arrested both Tregs and CD4+CD25- T cells in the G0/G1 phase and down-regulated the expression of FoxP3 and GITR. In western blotting analysis, nilotinib did not show significant inhibitory effects on TCR signaling events in Tregs and CD4+CD25- T cells. Conclusions These findings indicate that nilotinib does not hamper the function of Tregs at clinical relevant doses, while long-term administration of nilotinib still needs to be investigated.

  3. A chemically inert drug can stimulate T cells in vitro by their T cell receptor in non-sensitised individuals

    International Nuclear Information System (INIS)

    Engler, Olivier B.; Strasser, Ingrid; Naisbitt, Dean J.; Cerny, Andreas; Pichler, Werner J.

    2004-01-01

    Drugs can interact with T cell receptors (TCR) after binding to peptide-MHC structures. This binding may involve the formation of a stable, covalent bond between a chemically reactive drug and MHC or the peptide embedded within. Alternatively, if the drug is chemically inert, the binding may be non-covalent and readily reversible. Both types of drug presentation account for a substantial number of adverse side effects to drugs. Presently no tests are available to predict the ability of chemically inert drugs to stimulate an immune response. Here we present data on the successful induction of a primary T cell immune response in vitro against a chemically inert drug using blood from healthy individuals, previously not exposed to the drug. Blood lymphocytes were stimulated by the chemically inert drug sulfamethoxazole and the protein-reactive drug-metabolite sulfamethoxazole-nitroso in the presence of IL-2. 9/10 individuals reacted in response to sulfamethoxazole-nitroso, but only three reacted to the chemically inert compound sulfamethoxazole. Drug reactive T cells could be detected after 14-35 days of cell culture by drug-specific proliferation or cytotoxicity, which was MHC-restricted. These cells were CD4, CD8 positive or CD4/CD8 double positive and T cell clones generated secreted Th0 type cytokines. Drug interaction lead to down-regulation of specific TCR. These data confirm the ability of chemically inert drugs to stimulate certain T cells by their TCR and may provide the opportunity to screen new drugs for their ability to interact with TCRs

  4. Successful therapy of convoluted T-lymphoblastic lymphoma in the adult

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    Levine, A.M.; Forman, S.J.; Meyer, P.R.; Koehler, S.C.; Liebman, H.; Paganini-Hill, A.; Pockros, A.; Lukes, R.J.; Feinstein, D.I.

    1983-01-01

    Fifteen adult patients with biopsy-proven convoluted T-lymphoblastic lymphoma were treated with an aggressive regimen, modified from the LSA2-L2 protocol used for childhood lymphoma. The treatment schema consisted of induction phase, including cyclophosphamide, vincristine, prednisone, adriamycin, and 2000 rads to mediastinum, as well as intrathecal methotrexate. Consolidation phase included cytosine arabinoside, 6-thioguanine, L-asparaginase, and CCNU, along with cranial irradiation and further intrathecal methotrexate. Maintenance consisted of cyclical chemotherapy and intrathecal methotrexate, continuing for a total of 3 yr. Median age in the group was 25 yr (range 16-73). There were 8 males and 7 females. At diagnosis, 9 patients had mediastinal involvement, and 9 had bone marrow involvement. Five of these demonstrated malignant cells in the peripheral blood. Complete clinical response was attained in 11 patients. Three patients achieved partial response. Four complete responders have relapsed, 1 in the central nervous system at 6 mo. and 1 in nodal sites at 3 mo, 1 in multiple sites at 24 mo. and 1 in bone marrow at 42 mo while off all chemotherapy for 6 mos. At this time, median survival of all patients is 28.3 mo. and median relapse-free survival is 21 mo. The median survival for complete responders in excess of 71 mo. while the median relapse-free survival for this group is 41 mo.

  5. Inhibition of IGF1-R overcomes IGFBP7-induced chemotherapy resistance in T-ALL

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    Bartram, Isabelle; Erben, Ulrike; Ortiz-Tanchez, Jutta; Blunert, Katja; Schlee, Cornelia; Neumann, Martin; Heesch, Sandra; Baldus, Claudia D.

    2015-01-01

    T-cell acute lymphoblastic leukemia (T-ALL) is a genetically heterogeneous disease with the need for treatment optimization. Previously, high expression of Insulin-like growth factor binding protein 7 (IGFBP7), a member of the IGF system, was identified as negative prognostic factor in adult T-ALL patients. Since aberrant IGFBP7 expression was observed in a variety of neoplasia and was relevant for prognosis in T-ALL, we investigated the functional role of IGFBP7 in Jurkat and Molt-4 cells as in vitro models for T-ALL. Jurkat and Molt-4 cells were stably transfected with an IGFBP7 over-expression vector or the empty vector as control. Proliferation of the cells was assessed by WST-1 assays and cell cycle status was measured by flow-cytometry after BrDU/7-AAD staining. The effect of IGFBP7 over-expression on sensitivity to cytostatic drugs was determined in AnnexinV/7-AAD assays. IGF1-R protein expression was measured by Western Blot and flow-cytometric analysis. IGF1-R associated gene expression profiles were generated from microarray gene expression data of 86 T-ALL patients from the Microarrays Innovations in Leukemia (MILE) multicenter study. IGFBP7-transfected Jurkat cells proliferated less, leading to a longer survival in a nutrient–limited environment. Both IGFBP7-transfected Jurkat and Molt-4 cells showed an arrest in the G0/G1 cell cycle phase. Furthermore, Jurkat IGFBP7-transfected cells were resistant to vincristine and asparaginase treatment. Surface expression and whole protein measurement of IGF1-R protein expression showed a reduced abundance of the receptor after IGFBP7 transfection in Jurkat cells. Interestingly, combination of the IGF1-R inhibitor NPV-AEW541 restored sensitivity to vincristine in IGFBP7-transfected cells. Additionally, IGF1-R associated GEP revealed an up-regulation of important drivers of T-ALL pathogenesis and regulators of chemo-resistance and apoptosis such as NOTCH1, BCL-2, PRKCI, and TP53. This study revealed a

  6. Increased cellular immune responses and CD4+ T-cell proliferation correlate with reduced plasma viral load in SIV challenged recombinant simian varicella virus - simian immunodeficiency virus (rSVV-SIV vaccinated rhesus macaques

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    Pahar Bapi

    2012-08-01

    Full Text Available Abstract Background An effective AIDS vaccine remains one of the highest priorities in HIV-research. Our recent study showed that vaccination of rhesus macaques with recombinant simian varicella virus (rSVV vector – simian immunodeficiency virus (SIV envelope and gag genes, induced neutralizing antibodies and cellular immune responses to SIV and also significantly reduced plasma viral loads following intravenous pathogenic challenge with SIVMAC251/CX1. Findings The purpose of this study was to define cellular immunological correlates of protection in rSVV-SIV vaccinated and SIV challenged animals. Immunofluorescent staining and multifunctional assessment of SIV-specific T-cell responses were evaluated in both Experimental and Control vaccinated animal groups. Significant increases in the proliferating CD4+ T-cell population and polyfunctional T-cell responses were observed in all Experimental-vaccinated animals compared with the Control-vaccinated animals. Conclusions Increased CD4+ T-cell proliferation was significantly and inversely correlated with plasma viral load. Increased SIV-specific polyfunctional cytokine responses and increased proliferation of CD4+ T-cell may be crucial to control plasma viral loads in vaccinated and SIVMAC251/CX1 challenged macaques.

  7. Pulmonary stromal cells induce the generation of regulatory DC attenuating T-cell-mediated lung inflammation.

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    Li, Qian; Guo, Zhenhong; Xu, Xiongfei; Xia, Sheng; Cao, Xuetao

    2008-10-01

    The tissue microenvironment may affect the development and function of immune cells such as DC. Whether and how the pulmonary stromal microenvironment can affect the development and function of lung DC need to be investigated. Regulatory DC (DCreg) can regulate T-cell response. We wondered whether such regulatory DC exist in the lung and what is the effect of the pulmonary stromal microenvironment on the generation of DCreg. Here we demonstrate that murine pulmonary stromal cells can drive immature DC, which are regarded as being widely distributed in the lung, to proliferate and differentiate into a distinct subset of DCreg, which express high levels of CD11b but low levels of MHC class II (I-A), CD11c, secrete high amounts of IL-10, NO and prostaglandin E2 (PGE2) and suppress T-cell proliferation. The natural counterpart of DCreg in the lung with similar phenotype and regulatory function has been identified. Pulmonary stroma-derived TGF-beta is responsible for the differentiation of immature DC to DCreg, and DCreg-derived PGE2 contributes to their suppression of T-cell proliferation. Moreover, DCreg can induce the generation of CD4+CD25+Foxp3+ Treg. Importantly, infusion with DCreg attenuates T-cell-mediated eosinophilic airway inflammation in vivo. Therefore, the pulmonary microenvironment may drive the generation of DCreg, thus contributing to the maintenance of immune homoeostasis and the control of inflammation in the lung.

  8. Differentiation of human B lymphocyte subpopulations induced by an alloreactive helper T-cell clone

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    Anderson, S.J.; Hummell, D.S.; Lawton, A.R.

    1988-01-01

    We have used cloned alloreactive helper T cells to determine if direct T cell-B cell interaction can induce differentiation of human peripheral blood B cells which do not respond to pokeweed mitogen (PWM). T-cell clone 2F8 was derived from a one-way mixed lymphocyte reaction. 2F8 cells are T3+T4+T8-IL-2R+ and proliferate in response to irradiated stimulator cells, but not autologous cells, in the absence of exogenous interleukin-2. 2F8 cells provide allospecific help for polyclonal proliferation and differentiation of B cells in the absence of any other stimulus. The magnitude of this response is comparable to that of the response of the same B cells to PWM and fresh autologous T cells. 2F8 cells could also provide nonspecific help for unrelated donor B cells in the presence of PWM, with no requirement for costimulation by irradiated stimulator cells. Allospecific stimulation of B cells was completely inhibited by antibodies to class II major histocompatibility complex (MHC) framework determinants and was abrogated by 1000-rad irradiation. Cloned 2F8 T cells stimulated differentiation of both small, high-density B cells and larger B cells, generating up to 30% plasma cells with either fraction. B cells forming rosettes with mouse erythrocytes were also induced to differentiate by the helper T cell clone. As found previously, neither small, high-density B cells nor mouse rosette+ B cells responded well to PWM. Direct interaction with allospecific T cells induces differentiation of a broader spectrum of B cells than soluble growth and differentiation factors in conjunction with polyclonal activators such as PWM and protein A containing staphylococci

  9. Supernatural T cells: genetic modification of T cells for cancer therapy.

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    Kershaw, Michael H; Teng, Michele W L; Smyth, Mark J; Darcy, Phillip K

    2005-12-01

    Immunotherapy is receiving much attention as a means of treating cancer, but complete, durable responses remain rare for most malignancies. The natural immune system seems to have limitations and deficiencies that might affect its ability to control malignant disease. An alternative to relying on endogenous components in the immune repertoire is to generate lymphocytes with abilities that are greater than those of natural T cells, through genetic modification to produce 'supernatural' T cells. This Review describes how such T cells can circumvent many of the barriers that are inherent in the tumour microenvironment while optimizing T-cell specificity, activation, homing and antitumour function.

  10. Failure of itraconazole to prevent T-helper type 2 cell immune deviation: Implications for chronic rhinosinusitis.

    Science.gov (United States)

    Kennedy, Joshua L; Steinke, John W; Liu, Lixia; Negri, Julie; Borish, Larry; Payne, Spencer C

    2016-11-01

    T-helper (Th) type 2 cell inflammation is the hallmark of several disease processes, including asthma, atopic dermatitis, and some forms of chronic rhinosinusitis. Itraconazole has been used as both an antifungal and an anti-inflammatory agent, with some success in many of these diseases, in part, by altering Th2 cytokine expression by T cells. It is not known whether this merely reflects inhibition of established Th2-like cells or the inhibition of differentiation of naive T cells into Th2-like cells. To evaluate the role of itraconazole in the differentiation of naive T cells during activation. Naive CD45RA+ T cells were isolated from peripheral blood mononuclear cells from healthy volunteers. Th1 and Th2 type cells were differentiated in the presence of varying concentrations of itraconazole. After stimulation with anti-CD3 and anti-CD28 beads, carboxyfluorescein succinimidyl ester dilution was performed to evaluate proliferation and intracellular cytokine staining for interleukin (IL) 4 and interferon (IFN) gamma within proliferating T cells was measured along with enzyme-linked immunosorbent assay for secreted IL-5, IL-13, and IFN gamma. Itraconazole had no effect on proliferation of unbiased, Th1, or Th2 cells. Similarly, there was no effect of itraconazole on either intracellular cytokine staining of IL-4 and IFN gamma or secreted cytokine expression of IFN gamma, IL-5, and IL-13 in any of the cell populations. Itraconazole did not alter the ability of naive T cells to proliferate or secrete cytokines under Th1 or Th2 deviating conditions in vitro. As such, reported inhibition of Th2-like lymphocyte function by itraconazole reflected action on mature effector cells and may have underscored why antifungal treatment failed in many clinical trials of eosinophilic chronic rhinosinusitis.

  11. TNP-specific Lyt-2+ cytolytic T cell clones preferentially respond to TNP-conjugated epidermal cells

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    Shimada, S.; Katz, S.I.

    1985-01-01

    A most effective method for the induction of hapten-specific allergic contact sensitivity (CS) is via epicutaneous application of the hapten. Another effective method is by the administration of haptenated epidermal cells (EC) subcutaneously. The latter method induces more intense and longer lasting CS than does the subcutaneous administration of haptenated spleen cells (SC). Thus, there may be something unique about EC which, when haptenated, allows them to generate effector cells more effectively than do SC. The authors therefore, attempted to generate T cell clones that were both hapten- and epidermal-specific. Four days after painting mice with 7% trinitrochlorobenzene, draining lymph node cells were obtained and T cells were purified. These cells were co-cultured with trinitrophenylated (TNP) Langerhans cell-enriched EC. After 4 days, cells were harvested and rested on non-TNP-conjugated EC. The cells were restimulated and rested three times, and were then cloned by limiting dilution with added interleukin 2, which was then continually added. Proliferation of T cells was assessed by [ 3 H]-thymidine incorporation. Cytotoxicity assays utilized TNP-conjugated concanavalin A SC blasts or EC as targets. Clones A-2 and E-4 are Thy-1+, Lyt-2+, and L3T4-, and TNP-specific. In contrast to noncloned TNP-specific T cells, the clones proliferate preferentially in response to TNP-EC rather than TNP-SC. Also in contrast to noncloned T cells, the clones were preferentially cytotoxic for TNP-EC; compared to TNP-SC, there was an eight- to 32-fold increase in killing when TNP-EC were used as targets. Clones A-2 and E-4 therefore exhibit hapten and epidermal specificity

  12. Is there a role for B lymphocyte chimerism in the monitoring of B-acute lymphoblastic leukemia patients receiving allogeneic stem cell transplantation?

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    Yi-Ning Yang

    2015-03-01

    Full Text Available Objective: To determine the sensitivity and significance of B-cell chimerism for the detection of early engraftment, transplant rejection, and disease relapse. Methods: The dynamic monitoring of lineage-specific cell subtypes (B, T, and NK cells was made in 20 B-cell acute lymphoblastic leukemia (B-ALL patients following allogeneic hematopoietic stem cell transplantation (allo-HSCT. In the early period after allo-HSCT, the latest establishment of B-cell complete chimerism (CC was observed in a majority of patients. Results: The percentage of donor cells of B-cell lineage was lower than the percent of T-cell lineage in most of the mixed chimerism (MC patients. During graft rejection, the frequency of patients with decreasing MC of B-, T- and NK-cell lineage were 5/5, 2/5, and 2/5. When disease relapsed, five patients showed a faster decrease of the donor percent of B-cells than of T- or NK-cells. Only one patient displayed a more rapid decrease in NK-cells than in T- or B-cells. Conclusion: Monitoring of B-cell chimerism after HSCT seems to be valuable for insuring complete engraftment, anticipating graft rejection, and relapse in B-ALL patients. Keywords: B cell acute lymphoblastic leukemia (B-ALL, B-cell, T-cell, Chimerism, Allogeneic hematopoietic stem cell transplantation (allo-HSCT

  13. Human CD8 T cells generated in vitro from hematopoietic stem cells are functionally mature

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    Zúñiga-Pflücker Juan

    2011-03-01

    Full Text Available Abstract Background T cell development occurs within the highly specialized thymus. Cytotoxic CD8 T cells are critical in adaptive immunity by targeting virally infected or tumor cells. In this study, we addressed whether functional CD8 T cells can be generated fully in vitro using human umbilical cord blood (UCB hematopoietic stem cells (HSCs in coculture with OP9-DL1 cells. Results HSC/OP9-DL1 cocultures supported the differentiation of CD8 T cells, which were TCR/CD3hi CD27hi CD1aneg and thus phenotypically resembled mature functional CD8 single positive thymocytes. These in vitro-generated T cells also appeared to be conventional CD8 cells, as they expressed high levels of Eomes and low levels of Plzf, albeit not identical to ex vivo UCB CD8 T cells. Consistent with the phenotypic and molecular characterization, upon TCR-stimulation, in vitro-generated CD8 T cells proliferated, expressed activation markers (MHC-II, CD25, CD38, secreted IFN-γ and expressed Granzyme B, a cytotoxic T-cell effector molecule. Conclusion Taken together, the ability to direct human hematopoietic stem cell or T-progenitor cells towards a mature functional phenotype raises the possibility of establishing cell-based treatments for T-immunodeficiencies by rapidly restoring CD8 effector function, thereby mitigating the risks associated with opportunistic infections.

  14. Autoreactive effector/memory CD4+ and CD8+ T cells infiltrating grafted and endogenous islets in diabetic NOD mice exhibit similar T cell receptor usage.

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    Ramiro Diz

    Full Text Available Islet transplantation provides a "cure" for type 1 diabetes but is limited in part by recurrent autoimmunity mediated by β cell-specific CD4(+ and CD8(+ T cells. Insight into the T cell receptor (TCR repertoire of effector T cells driving recurrent autoimmunity would aid the development of immunotherapies to prevent islet graft rejection. Accordingly, we used a multi-parameter flow cytometry strategy to assess the TCR variable β (Vβ chain repertoires of T cell subsets involved in autoimmune-mediated rejection of islet grafts in diabetic NOD mouse recipients. Naïve CD4(+ and CD8(+ T cells exhibited a diverse TCR repertoire, which was similar in all tissues examined in NOD recipients including the pancreas and islet grafts. On the other hand, the effector/memory CD8(+ T cell repertoire in the islet graft was dominated by one to four TCR Vβ chains, and specific TCR Vβ chain usage varied from recipient to recipient. Similarly, islet graft- infiltrating effector/memory CD4(+ T cells expressed a limited number of prevalent TCR Vβ chains, although generally TCR repertoire diversity was increased compared to effector/memory CD8(+ T cells. Strikingly, the majority of NOD recipients showed an increase in TCR Vβ12-bearing effector/memory CD4(+ T cells in the islet graft, most of which were proliferating, indicating clonal expansion. Importantly, TCR Vβ usage by effector/memory CD4(+ and CD8(+ T cells infiltrating the islet graft exhibited greater similarity to the repertoire found in the pancreas as opposed to the draining renal lymph node, pancreatic lymph node, or spleen. Together these results demonstrate that effector/memory CD4(+ and CD8(+ T cells mediating autoimmune rejection of islet grafts are characterized by restricted TCR Vβ chain usage, and are similar to T cells that drive destruction of the endogenous islets.

  15. γδ T Cells Support Pancreatic Oncogenesis by Restraining αβ T Cell Activation.

    Science.gov (United States)

    Daley, Donnele; Zambirinis, Constantinos Pantelis; Seifert, Lena; Akkad, Neha; Mohan, Navyatha; Werba, Gregor; Barilla, Rocky; Torres-Hernandez, Alejandro; Hundeyin, Mautin; Mani, Vishnu Raj Kumar; Avanzi, Antonina; Tippens, Daniel; Narayanan, Rajkishen; Jang, Jung-Eun; Newman, Elliot; Pillarisetty, Venu Gopal; Dustin, Michael Loran; Bar-Sagi, Dafna; Hajdu, Cristina; Miller, George

    2016-09-08

    Inflammation is paramount in pancreatic oncogenesis. We identified a uniquely activated γδT cell population, which constituted ∼40% of tumor-infiltrating T cells in human pancreatic ductal adenocarcinoma (PDA). Recruitment and activation of γδT cells was contingent on diverse chemokine signals. Deletion, depletion, or blockade of γδT cell recruitment was protective against PDA and resulted in increased infiltration, activation, and Th1 polarization of αβT cells. Although αβT cells were dispensable to outcome in PDA, they became indispensable mediators of tumor protection upon γδT cell ablation. PDA-infiltrating γδT cells expressed high levels of exhaustion ligands and thereby negated adaptive anti-tumor immunity. Blockade of PD-L1 in γδT cells enhanced CD4(+) and CD8(+) T cell infiltration and immunogenicity and induced tumor protection suggesting that γδT cells are critical sources of immune-suppressive checkpoint ligands in PDA. We describe γδT cells as central regulators of effector T cell activation in cancer via novel cross-talk. Copyright © 2016 Elsevier Inc. All rights reserved.

  16. Human T Cell Memory: A Dynamic View

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    Derek C. Macallan

    2017-02-01

    Full Text Available Long-term T cell-mediated protection depends upon the formation of a pool of memory cells to protect against future pathogen challenge. In this review we argue that looking at T cell memory from a dynamic viewpoint can help in understanding how memory populations are maintained following pathogen exposure or vaccination. For example, a dynamic view resolves the apparent paradox between the relatively short lifespans of individual memory cells and very long-lived immunological memory by focussing on the persistence of clonal populations, rather than individual cells. Clonal survival is achieved by balancing proliferation, death and differentiation rates within and between identifiable phenotypic pools; such pools correspond broadly to sequential stages in the linear differentiation pathway. Each pool has its own characteristic kinetics, but only when considered as a population; single cells exhibit considerable heterogeneity. In humans, we tend to concentrate on circulating cells, but memory T cells in non-lymphoid tissues and bone marrow are increasingly recognised as critical for immune defence; their kinetics, however, remain largely unexplored. Considering vaccination from this viewpoint shifts the focus from the size of the primary response to the survival of the clone and enables identification of critical system pinch-points and opportunities to improve vaccine efficacy.

  17. Indoleamine 2,3-dioxygenase-expressing leukemic dendritic cells impair a leukemia-specific immune response by inducing potent T regulatory cells.

    Science.gov (United States)

    Curti, Antonio; Trabanelli, Sara; Onofri, Chiara; Aluigi, Michela; Salvestrini, Valentina; Ocadlikova, Darina; Evangelisti, Cecilia; Rutella, Sergio; De Cristofaro, Raimondo; Ottaviani, Emanuela; Baccarani, Michele; Lemoli, Roberto M

    2010-12-01

    The immunoregulatory enzyme indoleamine 2,3-dioxygenase, which catalyzes the conversion of tryptophan into kynurenine, is expressed in a significant subset of patients with acute myeloid leukemia, resulting in the inhibition of T-cell proliferation and the induction of regulatory T cells. Acute myeloid leukemia cells can be differentiated into dendritic cells, which have increased immunogenicity and have been proposed as vaccines against leukemia. Leukemic dendritic cells were generated from acute myeloid leukemia cells and used as stimulators in functional assays, including the induction of regulatory T cells. Indoleamine 2,3-dioxygenase expression in leukemic dendritic cells was evaluated at molecular, protein and enzymatic levels. We demonstrate that, after differentiation into dendritic cells, both indoleamine 2,3-dioxygenase-negative and indoleamine 2,3-dioxygenase-positive acute myeloid leukemia samples show induction and up-regulation of indoleamine 2,3-dioxygenase gene and protein, respectively. Indoleamine 2,3-dioxygenase-positive acute myeloid leukemia dendritic cells catabolize tryptophan into kynurenine metabolite and inhibit T-cell proliferation through an indoleamine 2,3-dioxygenase-dependent mechanism. Moreover, indoleamine 2,3-dioxygenase-positive leukemic dendritic cells increase the number of allogeneic and autologous CD4(+)CD25(+) Foxp3(+) T cells and this effect is completely abrogated by the indoleamine 2,3-dioxygenase-inhibitor, 1-methyl tryptophan. Purified CD4(+)CD25(+) T cells obtained from co-culture with indoleamine 2,3-dioxygenase-positive leukemic dendritic cells act as regulatory T cells as they inhibit naive T-cell proliferation and impair the complete maturation of normal dendritic cells. Importantly, leukemic dendritic cell-induced regulatory T cells are capable of in vitro suppression of a leukemia-specific T cell-mediated immune response, directed against the leukemia-associated antigen, Wilms' tumor protein. These data identify

  18. T-lineage acute lymphoblastic leukemia and parvovirus infection in a child with neurofibromastosis-1

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    Pallavi Agarwal

    2013-01-01

    Full Text Available Neurofibromatosis (NF-1 patients have an increased risk of developing malignancies most commonly rhabdomyosarcomas, optic gliomas, brain tumors and non-lymphocytic leukemias. Acute lymphoblastic leukemia (ALL has been infrequently reported in association with NF-1. We describe a rare association of NF-1, T-lineage ALL and parvovirus infection in a 12-year-old child. In addition, it is also to emphasize that a high index of suspicion should be kept for parvovirus B19 infection as a cause of bicytopenia/pancytopenia in ALL patients following induction chemotherapy.

  19. Homeostatic 'bystander' proliferation of human peripheral blood B cells in response to polyclonal T-cell stimulation in vitro.

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    Jasiulewicz, Aleksandra; Lisowska, Katarzyna A; Pietruczuk, Krzysztof; Frąckowiak, Joanna; Fulop, Tamas; Witkowski, Jacek M

    2015-11-01

    The mechanisms of maintenance of adequate numbers of B lymphocytes and of protective levels of immunoglobulins in the absence of antigenic (re)stimulation remain not fully understood. Meanwhile, our results presented here show that both peripheral blood naive and memory B cells can be activated strongly and non-specifically (in a mitogen-like fashion) in 5-day in vitro cultures of anti-CD3- or concanavalin A (Con A)-stimulated peripheral blood mononuclear cells of healthy people. This polyclonal, bystander activation of the B cells includes multiple divisions of most of them (assessed here by the flow cytometric technique of dividing cell tracking) and significant antibody [immunoglobulin M (IgM) and IgG] secretion. Observed proliferation of the CD19(+) B cells depends on contact with stimulated T helper (Th) cells (via CD40-CD40L interaction) and on the response of B cells to secreted interleukins IL-5, IL-10 and IL-4, and is correlated with the levels of these Th-derived molecules, while it does not involve the ligation of the BCR/CD19 complex. We suggest that the effect might reflect the situation occurring in vivo as the homeostatic proliferation of otherwise non-stimulated, peripheral B lymphocytes, providing an always ready pool for efficient antibody production to any new (or cognate) antigen challenge. © The Japanese Society for Immunology. 2015. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

  20. Gene expression profiles in BCL11B-siRNA treated malignant T cells

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    Grabarczyk Piotr

    2011-05-01

    Full Text Available Abstract Background Downregulation of the B-cell chronic lymphocytic leukemia (CLL/lymphoma11B (BCL11B gene by small interfering RNA (siRNA leads to growth inhibition and apoptosis of the human T-cell acute lymphoblastic leukemia (T-ALL cell line Molt-4. To further characterize the molecular mechanism, a global gene expression profile of BCL11B-siRNA -treated Molt-4 cells was established. The expression profiles of several genes were further validated in the BCL11B-siRNA -treated Molt-4 cells and primary T-ALL cells. Results 142 genes were found to be upregulated and 109 genes downregulated in the BCL11B-siRNA -treated Molt-4 cells by microarray analysis. Among apoptosis-related genes, three pro-apoptotic genes, TNFSF10, BIK, BNIP3, were upregulated and one anti-apoptotic gene, BCL2L1 was downregulated. Moreover, the expression of SPP1 and CREBBP genes involved in the transforming growth factor (TGF-β pathway was down 16-fold. Expression levels of TNFSF10, BCL2L1, SPP1, and CREBBP were also examined by real-time PCR. A similar expression pattern of TNFSF10, BCL2L1, and SPP1 was identified. However, CREBBP was not downregulated in the BLC11B-siRNA -treated Molt-4 cells. Conclusion BCL11B-siRNA treatment altered expression profiles of TNFSF10, BCL2L1, and SPP1 in both Molt-4 T cell line and primary T-ALL cells.