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Sample records for cell-induced t-cell proliferation

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

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    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.

  2. Suppression of T cell-induced osteoclast formation

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    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.

  3. Inhibition of ALK enzymatic activity in T-cell lymphoma cells induces apoptosis and suppresses proliferation and STAT3 phosphorylation independently of Jak3

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    Marzec, Michal; Kasprzycka, Monika; Ptasznik, Andrzej;

    2005-01-01

    Aberrant expression of the ALK tyrosine kinase as a chimeric protein with nucleophosmin (NPM) and other partners plays a key role in malignant cell transformation of T-lymphocytes and other cells. Here we report that two small-molecule, structurally related, quinazoline-type compounds, WHI-131...... and WHI-154, directly inhibit enzymatic activity of NPM/ALK as demonstrated by in vitro kinase assays using a synthetic tyrosine-rich oligopeptide and the kinase itself as the substrates. The inhibition of NPM/ALK activity resulted in malignant T cells in suppression of their growth, induction...... of apoptosis and inhibition of tyrosine phosphorylation of STAT3, the key effector of the NPM/ALK-induced oncogenesis. We also show that the STAT3 tyrosine phosphorylation is mediated in the malignant T cells by NPM/ALK independently of Jak3 kinase as evidenced by the presence of STAT3 phosphorylation...

  4. Recipient myeloid-derived immunomodulatory cells induce PD-1 ligand-dependent donor CD4+Foxp3+ regulatory T cell proliferation and donor-recipient immune tolerance after murine nonmyeloablative bone marrow transplantation.

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    van der Merwe, Marie; Abdelsamed, Hossam A; Seth, Aman; Ong, Taren; Vogel, Peter; Pillai, Asha B

    2013-12-01

    We showed previously that nonmyeloablative total lymphoid irradiation/rabbit anti-thymocyte serum (TLI/ATS) conditioning facilitates potent donor-recipient immune tolerance following bone marrow transplantation (BMT) across MHC barriers via recipient invariant NKT (iNKT) cell-derived IL-4-dependent expansion of donor Foxp3(+) naturally occurring regulatory T cells (nTregs). In this study, we report a more specific mechanism. Wild-type (WT) BALB/c (H-2(d)) hosts were administered TLI/ATS and BMT from WT or STAT6(-/-) C57BL/6 (H-2(b)) donors. Following STAT6(-/-) BMT, donor nTregs demonstrated no loss of proliferation in vivo, indicating that an IL-4-responsive population in the recipient, rather than the donor, drives donor nTreg proliferation. In graft-versus-host disease (GVHD) target organs, three recipient CD11b(+) cell subsets (Gr-1(high)CD11c(-), Gr-1(int)CD11c(-), and Gr-1(low)CD11c(+)) were enriched early after TLI/ATS + BMT versus total body irradiation/ATS + BMT. Gr-1(low)CD11c(+) cells induced potent H-2K(b+)CD4(+)Foxp3(+) nTreg proliferation in vitro in 72-h MLRs. Gr-1(low)CD11c(+) cells were reduced significantly in STAT6(-/-) and iNKT cell-deficient Jα18(-/-) BALB/c recipients after TLI/ATS + BMT. Depletion of CD11b(+) cells resulted in severe acute GVHD, and adoptive transfer of WT Gr-1(low)CD11c(+) cells to Jα18(-/-) BALB/c recipients of TLI/ATS + BMT restored day-6 donor Foxp3(+) nTreg proliferation and protection from CD8 effector T cell-mediated GVHD. Blockade of programmed death ligand 1 and 2, but not CD40, TGF-β signaling, arginase 1, or iNOS, inhibited nTreg proliferation in cocultures of recipient-derived Gr-1(low)CD11c(+) cells with donor nTregs. Through iNKT-dependent Th2 polarization, myeloid-derived immunomodulatory dendritic cells are expanded after nonmyeloablative TLI/ATS conditioning and allogeneic BMT, induce PD-1 ligand-dependent donor nTreg proliferation, and maintain potent graft-versus-host immune tolerance.

  5. Human retinal pigment epithelial cell-induced apoptosis in activated T cells

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    Jørgensen, A; Wiencke, A K; la Cour, M;

    1998-01-01

    induced apoptosis in several activated T-cell populations and T-cell lines, including T-cell antigen receptor (TCR)-CD3-negative T-cell lines. In contrast, RPE cells induced little or no apoptosis in resting peripheral T cells. Major histocompatibility complex (MHC) class II monoclonal antibodies, which...

  6. Human retinal pigment epithelial cell-induced apoptosis in activated T cells

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    Jørgensen, A; Wiencke, A K; la Cour, M;

    1998-01-01

    human retinal pigment epithelial (RPE) cells can induce apoptosis in activated T cells. METHODS: Fas ligand (FasL) expression was detected by flow cytometry and immunohistochemistry. Cultured RPE cells were cocultured with T-cell lines and peripheral blood lymphocytes for 6 hours to 2 days. Induction...... of apoptosis was detected by 7-amino-actinomycin D and annexin V staining. RESULTS: Retinal pigment epithelial cells expressed FasL and induced apoptosis in activated Fas+ T cells. Blocking of Fas-FasL interaction with antibody strongly inhibited RPE-mediated T-cell apoptosis. Retinal pigment epithelial cells...... induced apoptosis in several activated T-cell populations and T-cell lines, including T-cell antigen receptor (TCR)-CD3-negative T-cell lines. In contrast, RPE cells induced little or no apoptosis in resting peripheral T cells. Major histocompatibility complex (MHC) class II monoclonal antibodies, which...

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

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    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.

  8. Arachidonoyl-Phospholipid Remodeling in Proliferating Murine T Cells

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    Ando Soichiro

    2004-01-01

    Full Text Available Abstract Backgound Previous studies have shown that the functional capacity of T cells may be modulated by the composition of fatty acids within, and the release of fatty acids from membrane phospholipids, particulary containing arachidonic acid (AA. The remodeling of AA within membrane phospholipids of resting and proliferating CD4+ and CD8+ T cells is examined in this study. Results Splenic T cells were cultured in the presence or absence of anti-CD3 mAb for 48 h then labeled with [3H]AA for 20 min. In unstimulated cells, labeled AA was preferentially incorporated into the phosphoglycerides, phosphatidylcholine (PC followed by phosphatidylinositol (PI and phosphatidylethanolamine (PE. During a subsequent chase in unlabeled medium unstimulated CD4+ and CD8+ T cells demonstrated a significant and highly selective transfer of free, labeled AA into the PC pool. In contrast, proliferating CD4+ and CD8+ T cells distributed labeled [3H]AA predominantly into PI followed by PC and PE. Following a chase in AA-free medium, a decline in the content of [3H]AA-PC was observed in association with a comparable increase in [3H]AA-PE. Subsequent studies revealed that the cold AA content of all PE species was increased in proliferating T cells compared with that in non-cycling cells, but that enrichment in AA was observed only in the ether lipid fractions. Finally, proliferating T cells preincubated with [3H]AA exhibited a significant loss of labeled arachidonate in the PC fraction and an equivalent gain in labeled AA in 1-alk-1'-enyl-2-arachidonoyl-PE during a chase in unlabeled medium. Conclusion This apparent unidirectional transfer of AA from PC to ether-containing PE suggests the existence of a CoA-independent transacylase system in T cells and supports the hypothesis that arachidonoyl phospholipid remodeling may play a role in the regulation of cellular proliferation.

  9. CD8+ T cells induce platelet clearance in the liver via platelet desialylation in immune thrombocytopenia

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    Qiu, Jihua; Liu, Xuena; Li, Xiaoqing; Zhang, Xu; Han, Panpan; Zhou, Hai; Shao, Linlin; Hou, Yu; Min, Yanan; Kong, Zhangyuan; Wang, Yawen; Wei, Yu; Liu, Xinguang; Ni, Heyu; Peng, Jun; Hou, Ming

    2016-01-01

    In addition to antiplatelet autoantibodies, CD8+ cytotoxic T lymphocytes (CTLs) play an important role in the increased platelet destruction in immune thrombocytopenia (ITP). Recent studies have highlighted that platelet desialylation leads to platelet clearance via hepatocyte asialoglycoprotein receptors (ASGPRs). Whether CD8+ T cells induce platelet desialylation in ITP remains unclear. Here, we investigated the cytotoxicity of CD8+ T cells towards platelets and platelet desialylation in ITP. We found that the desialylation of fresh platelets was significantly higher in ITP patients with positive cytotoxicity of CD8+ T cells than those without cytotoxicity and controls. In vitro, CD8+ T cells from ITP patients with positive cytotoxicity induced significant platelet desialylation, neuraminidase-1 expression on the platelet surface, and platelet phagocytosis by hepatocytes. To study platelet survival and clearance in vivo, CD61 knockout mice were immunized and their CD8+ splenocytes were used. Platelets co-cultured with these CD8+ splenocytes demonstrated decreased survival in the circulation and increased phagocytosis in the liver. Both neuraminidase inhibitor and ASGPRs competitor significantly improved platelet survival and abrogated platelet clearance caused by CD8+ splenocytes. These findings suggest that CD8+ T cells induce platelet desialylation and platelet clearance in the liver in ITP, which may be a novel mechanism of ITP. PMID:27321376

  10. CD8(+) T cells induce platelet clearance in the liver via platelet desialylation in immune thrombocytopenia.

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    Qiu, Jihua; Liu, Xuena; Li, Xiaoqing; Zhang, Xu; Han, Panpan; Zhou, Hai; Shao, Linlin; Hou, Yu; Min, Yanan; Kong, Zhangyuan; Wang, Yawen; Wei, Yu; Liu, Xinguang; Ni, Heyu; Peng, Jun; Hou, Ming

    2016-01-01

    In addition to antiplatelet autoantibodies, CD8(+) cytotoxic T lymphocytes (CTLs) play an important role in the increased platelet destruction in immune thrombocytopenia (ITP). Recent studies have highlighted that platelet desialylation leads to platelet clearance via hepatocyte asialoglycoprotein receptors (ASGPRs). Whether CD8(+) T cells induce platelet desialylation in ITP remains unclear. Here, we investigated the cytotoxicity of CD8(+) T cells towards platelets and platelet desialylation in ITP. We found that the desialylation of fresh platelets was significantly higher in ITP patients with positive cytotoxicity of CD8(+) T cells than those without cytotoxicity and controls. In vitro, CD8(+) T cells from ITP patients with positive cytotoxicity induced significant platelet desialylation, neuraminidase-1 expression on the platelet surface, and platelet phagocytosis by hepatocytes. To study platelet survival and clearance in vivo, CD61 knockout mice were immunized and their CD8(+) splenocytes were used. Platelets co-cultured with these CD8(+) splenocytes demonstrated decreased survival in the circulation and increased phagocytosis in the liver. Both neuraminidase inhibitor and ASGPRs competitor significantly improved platelet survival and abrogated platelet clearance caused by CD8(+) splenocytes. These findings suggest that CD8(+) T cells induce platelet desialylation and platelet clearance in the liver in ITP, which may be a novel mechanism of ITP. PMID:27321376

  11. DIABETOGENIC T CELLS INDUCE AUTOIMMUNE DIABETES IN BALB/c MICE

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    Xiao-lei Zou; Zeng-yu Zhao; Yun-yang Wang; Zhi-qiang Su; Ming Xiang

    2008-01-01

    Objective To investigate the role of T cell and its subsets in the induction of insulitis and type 1 diabetes meilitus(T1DM) in BALB/c mice.Methods Autoimmune diabetes mellitus was developed by intraperitoneal injection of 40 mg/kg streptozotocin(STZ) daily for 5 consecutive days in BALB/c mice as sources of donor cells. Spleen cells from diabetic mice were then cultured for 7 days in the stimulation of interleukin-2 ( IL-2 ) to harvest diabetogenic T cells, which were subsequently transferred into normal BALB/c mice recipients. MTr, ELISA, and HE staining were used to analyze the lymphocyte proliferation, cytokine (IL-2, interferon-γ, IL-4, and IL-10) levels, and pathological changes in pancreatic islets.Results As few as 3 × 106 diabetogenic T cells successfully induced diabetes meilitus in recipients pretreated with STZ twice, whereas transfer of equal amount of normal splenocytes, T cell-depleted diabetogenie splenocytes, or diabetogenic CD4+ T cells alone in recipients receiving STZ twice pretreatment was proved not to induce diabetes mellitus either. A markedly increased lymphocyte proliferation, high levels of interferon-γ and IL-2 in the supematants of diabetogenie T cells were observed. In addition, a markedly enhanced lymphocyte proliferation, a high level of interferon-γ secretion in serum, and numerous lymphocytes infiltration in pancreatic islets were detected in the diabetic mice induced by diabetogenic T cells transfer.Conclusions A novel T1DM murine model is established in STZ-pretreated BALB/c mice by adoptive transfer of diabetogenic T cells. CD4M+ T cells with interferon-γ may promote the onset of diabetes mellitus.

  12. Nod2 activates NF-kB in CD4+ T cells but its expression is dispensable for T cell-induced colitis.

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    Galliano Zanello

    Full Text Available Although the etiology of Crohn's disease (CD remains elusive this disease is characterized by T cell activation that leads to chronic inflammation and mucosal damage. A potential role for maladaptation between the intestinal microbiota and the mucosal immune response is suggested by the fact that mutations in the pattern recognition receptor Nod2 are associated with higher risks for developing CD. Although Nod2 deletion in CD4(+ T cells has been shown to impair the induction of colitis in the murine T cell transfer model, the analysis of T cell intrinsic Nod2 function in T cell differentiation and T cell-mediated immunity is inconsistent between several studies. In addition, the role of T cell intrinsic Nod2 in regulatory T cell (Treg development and function during colitis remain to be analyzed. In this study, we show that Nod2 expression is higher in activated/memory CD4(+ T cells and its expression was inducible after T cell receptor (TCR ligation. Nod2 stimulation with muramyl dipeptide (MDP led to a nuclear accumulation of c-Rel NF-kB subunit. Although functionally active in CD4(+ T cells, the deletion of Nod2 did not impair the induction and the prevention of colitis in the T cell transfer model. Moreover, Nod2 deletion did not affect the development of Foxp3(+ Treg cells in the spleen of recipient mice and Nod2 deficient CD4 T cells expressing the OVA specific transgenic TCR were able to differentiate in Foxp3(+ Treg cells after OVA feeding. In vitro, CD25(+ Nod2 deficient T cells suppressed T cell proliferation as well as wild type counter parts and T cell stimulation with MDP did not affect the proliferation and the cytokine secretion of T cells. In conclusion, our data indicate that Nod2 is functional in murine CD4(+ T cells but its expression is dispensable for the T cell regulation of colitis.

  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

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    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. Regulatory CD8{sup +} T cells induced by exposure to all-trans retinoic acid and TGF-{beta} suppress autoimmune diabetes

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    Kishi, Minoru [Department of Internal and Geriatric Medicine, Kobe University Graduate School of Medicine, 7-5-1 Kusunoki-cho, Chuo-ku, Kobe 650-0017 (Japan); Yasuda, Hisafumi, E-mail: yasuda@med.kobe-u.ac.jp [Department of Internal and Geriatric Medicine, Kobe University Graduate School of Medicine, 7-5-1 Kusunoki-cho, Chuo-ku, Kobe 650-0017 (Japan); Abe, Yasuhisa; Sasaki, Hirotomo; Shimizu, Mami; Arai, Takashi; Okumachi, Yasuyo; Moriyama, Hiroaki; Hara, Kenta; Yokono, Koichi; Nagata, Masao [Department of Internal and Geriatric Medicine, Kobe University Graduate School of Medicine, 7-5-1 Kusunoki-cho, Chuo-ku, Kobe 650-0017 (Japan)

    2010-03-26

    Antigen-specific regulatory CD4{sup +} T cells have been described but there are few reports on regulatory CD8{sup +} T cells. We generated islet-specific glucose-6-phosphatase catalytic subunit-related protein (IGRP)-specific regulatory CD8{sup +} T cells from 8.3-NOD transgenic mice. CD8{sup +} T cells from 8.3-NOD splenocytes were cultured with IGRP, splenic dendritic cells (SpDCs), TGF-{beta}, and all-trans retinoic acid (ATRA) for 5 days. CD8{sup +} T cells cultured with either IGRP alone or IGRP and SpDCs in the absence of TGF-{beta} and ATRA had low Foxp3{sup +} expression (1.7 {+-} 0.9% and 3.2 {+-} 4.5%, respectively). In contrast, CD8{sup +} T cells induced by exposure to IGRP, SpDCs, TGF-{beta}, and ATRA showed the highest expression of Foxp3{sup +} in IGRP-reactive CD8{sup +} T cells (36.1 {+-} 10.6%), which was approximately 40-fold increase compared with that before induction culture. CD25 expression on CD8{sup +} T cells cultured with IGRP, SpDCs, TGF-{beta}, and ATRA was only 7.42%, whereas CD103 expression was greater than 90%. These CD8{sup +} T cells suppressed the proliferation of diabetogenic CD8{sup +} T cells from 8.3-NOD splenocytes in vitro and completely prevented diabetes onset in NOD-scid mice in cotransfer experiments with diabetogenic splenocytes from NOD mice in vivo. Here we show that exposure to ATRA and TGF-{beta} induces CD8{sup +}Foxp3{sup +} T cells ex vivo, which suppress diabetogenic T cells in vitro and in vivo.

  15. Allosuppressor- and allohelper-T cells in acute and chronic graft-vs. -host (GVH) disease. III. Different Lyt subsets of donor T cells induce different pathological syndromes

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    Rolink, A.G.; Gleichmann, E.

    1983-08-01

    Previous work from this laboratory has led to the hypothesis that the stimulatory pathological symptoms of chronic graft-vs.-host disease (GVHD) are caused by alloreactive donor T helper (TH) cells, whereas the suppressive pathological symptoms of acute GVHD are caused by alloreactive T suppressor (TS) cells of the donor. We analyzed the Lyt phenotypes of B10 donor T cells required for the induction of either acute or chronic GVHD in H-2-different (B10 X DBA/2)F1 recipients. When nonirradiated F1 mice were used as the recipients, we found unseparated B10 T cells induced only a moderate formation of systemic lupus erythematosus (SLE)-like autoantibodies, but a high percentage of lethal GVHD (LGVHD). In contrast, Lyt-1+2- donor T cells were unable to induce LGVHD in these recipients but were capable of inducing a vigorous formation of SLE-like autoantibodies and severe immune-complex glomerulonephritis. Lyt-1-2+ T cells were incapable of inducing either acute or chronic GVHD. The sensitivity and accuracy of the GVH system were increased by using irradiated F1 mice as recipients and then comparing donor-cell inocula that contained similar numbers of T lymphocytes. Donor-cell inocula were used that had been tested for their allohelper and allosuppressor effects on F1 B cells in vitro. In the irradiated F1 recipients unseparated donor T cells were superior to T cell subsets in inducing LGVHD. In contrast Lyt-1+2- T cells, but neither unseparated T cells nor Lyt-1-2+ T cells, were capable of inducing a vigorous formation of SLE-like auto-antibodies. We conclude that the stimulatory pathological symptoms of chronic GVHD are caused by Lyt-1+2- allohelper T cells. In contrast, the development of the suppressive pathological symptoms of acute GVHD appears to involve alloreactive Lyt-1+2+ T suppressor cells.

  16. Human regulatory T cells suppress proliferation of B lymphoma cells.

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    Grygorowicz, Monika Anna; Biernacka, Marzena; Bujko, Mateusz; Nowak, Eliza; Rymkiewicz, Grzegorz; Paszkiewicz-Kozik, Ewa; Borycka, Ilona Sara; Bystydzienski, Zbigniew; Walewski, Jan; Markowicz, Sergiusz

    2016-08-01

    Activated regulatory T cells (Tregs) suppress proliferation and differentiation of normal B cells. In our study, allogeneic polyclonal CD4 (+) CD25 (+) Tregs and CD4 (+) CD25 (+) CD127(lo)Tregs expanded in vitro in the presence of rapamycin and low dose IL-2 suppressed proliferation of 11 out of 12 established lymphoma B-cell lines. The effect of expanded CD4 (+) CD25 (+) Tregs on survival of freshly isolated lymphoma B cells maintained in culture with soluble multimeric CD40L and IL-4 was variable across lymphoma entities. The survival of freshly isolated follicular lymphoma cells usually decreased in cocultures with CD4 (+) CD25 (+) Tregs. Treg effect on chronic lymphocytic leukemia/small lymphocytic lymphoma cells ranged from suppression to help in individual patients. CD4 (+) CD25 (+) Tregs or CD4 (+) CD25 (+) CD127(lo)Tregs expanded ex vivo with rapamycin could be used to suppress regrowth of residual lymphoma after autologous hematopoietic cell transplantation (HCT), and to counteract both graft-versus-host disease and lymphoma re-growth after allogeneic HCT in select patients with lymphoma susceptible to the regulation by Tregs. PMID:26758248

  17. Blockade of Retinol Metabolism Protects T Cell-Induced Hepatitis by Increasing Migration of Regulatory T Cells.

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    Lee, Young-Sun; Yi, Hyon-Seung; Suh, Yang-Gun; Byun, Jin-Seok; Eun, Hyuk Soo; Kim, So Yeon; Seo, Wonhyo; Jeong, Jong-Min; Choi, Won-Mook; Kim, Myung-Ho; Kim, Ji Hoon; Park, Keun-Gyu; Jeong, Won-Il

    2015-11-01

    Retinols are metabolized into retinoic acids by alcohol dehydrogenase (ADH) and retinaldehyde dehydrogenase (Raldh). However, their roles have yet to be clarified in hepatitis despite enriched retinols in hepatic stellate cells (HSCs). Therefore, we investigated the effects of retinols on Concanavalin A (Con A)-mediated hepatitis. Con A was injected into wild type (WT), Raldh1 knock-out (Raldh1(-/-)), CCL2(-/-) and CCR2(-/-) mice. For migration study of regulatory T cells (Tregs), we used in vivo and ex vivo adoptive transfer systems. Blockade of retinol metabolism in mice given 4-methylpyrazole, an inhibitor of ADH, and ablated Raldh1 gene manifested increased migration of Tregs, eventually protected against Con A-mediated hepatitis by decreasing interferon-γ in T cells. Moreover, interferon-γ treatment increased the expression of ADH3 and Raldh1, but it suppressed that of CCL2 and IL-6 in HSCs. However, the expression of CCL2 and IL-6 was inversely increased upon the pharmacologic or genetic ablation of ADH3 and Raldh1 in HSCs. Indeed, IL-6 treatment increased CCR2 expression of Tregs. In migration assay, ablated CCR2 in Tregs showed reduced migration to HSCs. In adoptive transfer of Tregs in vivo and ex vivo, Raldh1-deficient mice showed more increased migration of Tregs than WT mice. Furthermore, inhibited retinol metabolism increased survival rate (75%) compared with that of the controls (25%) in Con A-induced hepatitis. These results suggest that blockade of retinol metabolism protects against acute liver injury by increased Treg migration, and it may represent a novel therapeutic strategy to control T cell-mediated acute hepatitis. PMID:26537191

  18. Artesunate inhibits proliferation of naïve CD4(+) T cells but enhances function of effector T cells.

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    Lee, Sung Ho; Cho, Young-Chang; Kim, Kyung Hee; Lee, Ik-Soo; Choi, Hyun Jin; Kang, Bok Yun

    2015-06-01

    Artesunate is an artemisinin derivative from Artemisia annua and is being applied as a first-line drug for malaria treatment. In addition to anti-malarial effects, anti-cancer, anti-viral, and anti-inflammatory activities have been reported for artemisinin derivatives. In this study, we investigated the effects of artesunate on naïve T cell activation and Th1/Th2 differentiation. Artesunate inhibited the proliferation of CD4(+) T cells and the production of IL-2, T cell growth factor. Moreover, artesunate reduced the expression of cell surface protein CD25 (IL-2 receptor alpha chain) and CD69 on CD4(+) T cells. Artesunate showed inhibitory effects on naïve T cell activation but artesunate increased the production of IFN-γ and IL-4 under Th1 and Th2 skewed condition respectively. Therefore, these results suggest that artesunate has a negative mitogenic effect on CD4(+) T cells but reinforces the function of effector T cells. PMID:25370606

  19. Generation of the First TCR Transgenic Mouse with CD4+ T Cells Recognizing an Anti-inflammatory Regulatory T Cell-Inducing Hsp70 Peptide

    Science.gov (United States)

    Jansen, Manon A. A.; van Herwijnen, Martijn J. C.; van Kooten, Peter J. S.; Hoek, Aad; van der Zee, Ruurd; van Eden, Willem; Broere, Femke

    2016-01-01

    Antigen-specific regulatory T cells (Tregs) directed at self-antigens are difficult to study since suitable specific tools to isolate and characterize these cells are lacking. A T cell receptor (TCR)-transgenic mouse would generate possibilities to study such ­antigen-specific T cells. As was shown previously, immunization with the mycobacterial heat shock protein (Hsp) 70-derived peptide B29 and its mouse homologs mB29a and mB29b induced anti-inflammatory responses. Furthermore, B29 induced antigen-­specific Tregs in vivo. To study mB29b-specific Tregs, we isolated the TCR from T cell hybridomas generated against mB29b and produced a TCR transgenic mouse that expresses a MHC-class II restricted mB29b-specific TCR. These TCR transgenic CD4+ T cells were found to cross-react with the B29 epitope as identified with peptide-induced proliferation and IL-2 production. Thus, we have successfully generated a novel mouse model with antigen-specific CD4+ T cells that recognize self and bacterial Hsp 70-derived peptides. With this novel mouse model, it will be possible to study primary antigen-specific T cells with specificity for a regulatory Hsp70 T cell epitope. This will enable the isolation and characterization CD4+CD25+ Tregs with a proven specificity. This will provide useful knowledge of the induction, activation, and mode of action of Hsp70-specific Tregs, for instance, during experimental arthritis. PMID:27014269

  20. Generation of the First TCR Transgenic Mouse with CD4(+) T Cells Recognizing an Anti-inflammatory Regulatory T Cell-Inducing Hsp70 Peptide.

    Science.gov (United States)

    Jansen, Manon A A; van Herwijnen, Martijn J C; van Kooten, Peter J S; Hoek, Aad; van der Zee, Ruurd; van Eden, Willem; Broere, Femke

    2016-01-01

    Antigen-specific regulatory T cells (Tregs) directed at self-antigens are difficult to study since suitable specific tools to isolate and characterize these cells are lacking. A T cell receptor (TCR)-transgenic mouse would generate possibilities to study such -antigen-specific T cells. As was shown previously, immunization with the mycobacterial heat shock protein (Hsp) 70-derived peptide B29 and its mouse homologs mB29a and mB29b induced anti-inflammatory responses. Furthermore, B29 induced antigen--specific Tregs in vivo. To study mB29b-specific Tregs, we isolated the TCR from T cell hybridomas generated against mB29b and produced a TCR transgenic mouse that expresses a MHC-class II restricted mB29b-specific TCR. These TCR transgenic CD4(+) T cells were found to cross-react with the B29 epitope as identified with peptide-induced proliferation and IL-2 production. Thus, we have successfully generated a novel mouse model with antigen-specific CD4(+) T cells that recognize self and bacterial Hsp 70-derived peptides. With this novel mouse model, it will be possible to study primary antigen-specific T cells with specificity for a regulatory Hsp70 T cell epitope. This will enable the isolation and characterization CD4(+)CD25(+) Tregs with a proven specificity. This will provide useful knowledge of the induction, activation, and mode of action of Hsp70-specific Tregs, for instance, during experimental arthritis. PMID:27014269

  1. An IFN-gamma-IL-18 signaling loop accelerates memory CD8+ T cell proliferation.

    Directory of Open Access Journals (Sweden)

    Yoshiko Iwai

    Full Text Available Rapid proliferation is one of the important features of memory CD8(+ T cells, ensuring rapid clearance of reinfection. Although several cytokines such as IL-15 and IL-7 regulate relatively slow homeostatic proliferation of memory T cells during the maintenance phase, it is unknown how memory T cells can proliferate more quickly than naïve T cells upon antigen stimulation. To examine antigen-specific CD8(+ T cell proliferation in recall responses in vivo, we targeted a model antigen, ovalbumin(OVA, to DEC-205(+ dendritic cells (DCs with a CD40 maturation stimulus. This led to the induction of functional memory CD8(+ T cells, which showed rapid proliferation and multiple cytokine production (IFN-gamma, IL-2, TNF-alpha during the secondary challenge to DC-targeted antigen. Upon antigen-presentation, IL-18, an IFN-gamma-inducing factor, accumulated at the DC:T cell synapse. Surprisingly, IFN-gamma receptors were required to augment IL-18 production from DCs. Mice genetically deficient for IL-18 or IFN-gamma-receptor 1 also showed delayed expansion of memory CD8(+ T cells in vivo. These results indicate that a positive regulatory loop involving IFN-gamma and IL-18 signaling contributes to the accelerated memory CD8(+ T cell proliferation during a recall response to antigen presented by DCs.

  2. T cells induce extended class II MHC compartments in dendritic cells in a Toll-like receptor-dependent manner.

    Science.gov (United States)

    Boes, Marianne; Bertho, Nicolas; Cerny, Jan; Op den Brouw, Marjolein; Kirchhausen, Tomas; Ploegh, Hidde

    2003-10-15

    Interaction of Ag-loaded dendritic cells with Ag-specific CD4 T cells induces the formation of long tubular class II MHC-positive compartments that polarize toward the T cell. We show involvement of a Toll-like receptor-mediated signal in this unusual form of intracellular class II MHC trafficking. First, wild-type dendritic cells loaded with LPS-free Ag failed to show formation of class II-positive tubules upon Ag-specific T cell engagement, but did so upon supplementation of the Ag with low concentrations of LPS. Second, Ag-loaded myeloid differentiation factor 88 -deficient dendritic cells failed to form these tubules upon interaction with T cells, regardless of the presence of LPS. Finally, inclusion of a cell-permeable peptide that blocks TNFR-associated factor 6 function, downstream of myeloid differentiation factor 88, blocked T cell-dependent tubulation. A Toll-like receptor-dependent signal is thus required to allow Ag-loaded dendritic cells to respond to T cell contact by formation of extended endosomal compartments. This activation does not result in massive translocation of class II MHC molecules to the cell surface.

  3. Clonal Expansion and Cytotoxicity of TCRVβ Subfamily T Cells Induced by CML and K562 Cells

    Institute of Scientific and Technical Information of China (English)

    YupingZHang; YangqiuLi; ShaohuaChen; LijianYang; GengxinLuo; XueliZhang

    2004-01-01

    OBJECTIVE To investigate the anti-leukemia effect, the distribution and clonal expansion of TCRVβ subfamily T cells in T cells from cord blood and adult peripheral blood induced by CML cells and K562 cells in vitro. METHODS Peripheral blood T cells from one adult donor and 3 cases of cord blood were stimulated with CML cells and K562 cells and further amplified by a suspended T cell-bulk culture,in order to induce CML specific cytotoxic T lymphocytes. The induced T cells were further analyzed for the specific cytotoxicity in CML by LDH assay, the phenotype identification by indirect immunofiuorescence technique and the distribution and clonal expansion of TCRVβ subfamily by using reverse transcriptase-polymerase chain reaction (RT-PCR) and genescan analysis, respectively. RESULTS Oligoclonal and oligoclonal tendency T cells with higher specific cytotoxicity from cord blood and adult peripheral blood could be induced by stimulation with CML cells and K562 cells. CONCLUSIONS Specific cytotoxic T cells for an anti-CML effect could be induced by CML cells and K562 cells .The induced T cells which have the characteristic of specific cytotoxicity against CML cells may come from the clonal expansion of TCRVβ subfamily T cells.

  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

    The purpose of this study was to characterize the effects of human retinal pigment epithelial (RPE) cells on activated T cells. Activated T cells were cocultured with adult and foetal human RPE cells whereafter apoptosis and proliferation were determined by flow cytometry and (3)H......-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...

  5. A role for Peroxisome Proliferator-Activated Receptor Beta in T cell development

    Science.gov (United States)

    Mothe-Satney, Isabelle; Murdaca, Joseph; Sibille, Brigitte; Rousseau, Anne-Sophie; Squillace, Raphaëlle; Le Menn, Gwenaëlle; Rekima, Akila; Larbret, Frederic; Pelé, Juline; Verhasselt, Valérie; Grimaldi, Paul A.; Neels, Jaap G.

    2016-01-01

    Metabolism plays an important role in T cell biology and changes in metabolism drive T cell differentiation and fate. Most research on the role of metabolism in T lymphocytes focuses on mature T cells while only few studies have investigated the role of metabolism in T cell development. In this study, we report that activation or overexpression of the transcription factor Peroxisome Proliferator-Activated Receptor β (PPARβ) increases fatty acid oxidation in T cells. Furthermore, using both in vivo and in vitro models, we demonstrate that PPARβ activation/overexpression inhibits thymic T cell development by decreasing proliferation of CD4−CD8− double-negative stage 4 (DN4) thymocytes. These results support a model where PPARβ activation/overexpression favours fatty acid- instead of glucose-oxidation in developing T cells, thereby hampering the proliferative burst normally occurring at the DN4 stage of T cell development. As a consequence, the αβ T cells that are derived from DN4 thymocytes are dramatically decreased in peripheral lymphoid tissues, while the γδ T cell population remains untouched. This is the first report of a direct role for a member of the PPAR family of nuclear receptors in the development of T cells. PMID:27680392

  6. Surfactant protein A integrates activation signal strength to differentially modulate T cell proliferation.

    Science.gov (United States)

    Mukherjee, Sambuddho; Giamberardino, Charles; Thomas, Joseph; Evans, Kathy; Goto, Hisatsugu; Ledford, Julie G; Hsia, Bethany; Pastva, Amy M; Wright, Jo Rae

    2012-02-01

    Pulmonary surfactant lipoproteins lower the surface tension at the alveolar-airway interface of the lung and participate in host defense. Previous studies reported that surfactant protein A (SP-A) inhibits lymphocyte proliferation. We hypothesized that SP-A-mediated modulation of T cell activation depends upon the strength, duration, and type of lymphocyte activating signals. Modulation of T cell signal strength imparted by different activating agents ex vivo and in vivo in different mouse models and in vitro with human T cells shows a strong correlation between strength of signal (SoS) and functional effects of SP-A interactions. T cell proliferation is enhanced in the presence of SP-A at low SoS imparted by exogenous mitogens, specific Abs, APCs, or in homeostatic proliferation. Proliferation is inhibited at higher SoS imparted by different doses of the same T cell mitogens or indirect stimuli such as LPS. Importantly, reconstitution with exogenous SP-A into the lungs of SP-A(-/-) mice stimulated with a strong signal also resulted in suppression of T cell proliferation while elevating baseline proliferation in unstimulated T cells. These signal strength and SP-A-dependent effects are mediated by changes in intracellular Ca(2+) levels over time, involving extrinsic Ca(2+)-activated channels late during activation. These effects are intrinsic to the global T cell population and are manifested in vivo in naive as well as memory phenotype T cells. Thus, SP-A appears to integrate signal thresholds to control T cell proliferation. PMID:22219327

  7. Human retinal pigment epithelial cell-induced apoptosis in activated T cells

    DEFF Research Database (Denmark)

    Jørgensen, A; Wiencke, A K; la Cour, M;

    1998-01-01

    PURPOSE: The immune privilege of the eye has been thought to be dependent on physical barriers and absence of lymphatic vessels. However, the immune privilege may also involve active immunologic processes, as recent studies have indicated. The purpose of the present study was to investigate whether...... human retinal pigment epithelial (RPE) cells can induce apoptosis in activated T cells. METHODS: Fas ligand (FasL) expression was detected by flow cytometry and immunohistochemistry. Cultured RPE cells were cocultured with T-cell lines and peripheral blood lymphocytes for 6 hours to 2 days. Induction...... of apoptosis was detected by 7-amino-actinomycin D and annexin V staining. RESULTS: Retinal pigment epithelial cells expressed FasL and induced apoptosis in activated Fas+ T cells. Blocking of Fas-FasL interaction with antibody strongly inhibited RPE-mediated T-cell apoptosis. Retinal pigment epithelial cells...

  8. PSGL-1 regulates the migration and proliferation of CD8(+) T cells under homeostatic conditions.

    Science.gov (United States)

    Veerman, Krystle M; Carlow, Douglas A; Shanina, Iryna; Priatel, John J; Horwitz, Marc S; Ziltener, Hermann J

    2012-02-15

    P-selectin glycoprotein ligand-1 (PSGL-1), a heavily glycosylated sialomucin expressed on most leukocytes, has dual function as a selectin ligand for leukocyte rolling on vascular selectins expressed in inflammation and as a facilitator of resting T cell homing into lymphoid organs. In this article, we document disturbances in T cell homeostasis present in PSGL-1(null) mice. Naive CD4(+) and CD8(+) T cell frequencies were profoundly reduced in blood, whereas T cell numbers in lymph nodes and spleen were at or near normal levels. Although PSGL-1(null) T cells were less efficient at entering lymph nodes, they also remained in lymph nodes longer than PSGL-1(+/+) T cells, suggesting that PSGL-1 supports T cell egress. In addition, PSGL-1(null) CD8(+) T cell proliferation was observed under steady-state conditions and PSGL-1(null) CD8(+) T cells were found to be hyperresponsive to homeostatic cytokines IL-2, IL-4, and IL-15. Despite these disturbances in T cell homeostasis, PSGL-1(null) mice exhibited a normal acute response (day 8) to lymphocytic choriomeningitis virus infection but generated an increased frequency of memory T cells (day 40). Our observations demonstrate a novel pleiotropic influence of PSGL-1 deficiency on several aspects of T cell homeostasis that would not have been anticipated based on the mild phenotype of PSGL-1(null) mice. These potentially offsetting effects presumably account for the near-normal cellularity seen in lymph nodes of PSGL-1(null) mice.

  9. Antibody-targeting of steady state dendritic cells induces tolerance mediated by regulatory T cells

    Directory of Open Access Journals (Sweden)

    Karsten eMahnke

    2016-02-01

    Full Text Available Dendritic cells (DCs are often defined as pivotal inducers of immunity, but these proinflammatory properties only develop after stimulation or ex vivo manipulation of DCs. Under non-inflammatory conditions in vivo, DCs are embedded into a tissue environment and encounter a plethora of self-antigens derived from apoptotic material. This material is transported to secondary lymphoid organs. As DCs maintain their non-activated phenotype in a sterile tissue environment, interaction with T cells will induce rather regulatory T cells (Treg than effector T cells. Thus, DCs are not only inducers of immunity but are also critical for maintenance of peripheral tolerance. Therapeutical intervention for the induction of long lasting tolerance in several autoimmune conditions may therefore be possible by manipulating DC activation and/or targeting of DCs in their natural tissue environment.

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

    OpenAIRE

    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.

    2015-01-01

    This study compared second generation chimeric antigen receptors encoding signaling domains composed of CD28, ICOS and 4-1BB. Here we report that certain CARs endow T cells with the ability to undergo long-term autonomous proliferation. Transduction of primary human T-cell with lentiviral vectors encoding some of the CARs resulted in sustained proliferation for up to three months following a single stimulation through the TCR. Sustained numeric expansion was independent of cognate antigen and...

  11. The mitochondrial phospholipid cardiolipin is involved in the regulation of T-cell proliferation.

    Science.gov (United States)

    Mürke, Eik; Stoll, Steffan; Lendeckel, Uwe; Reinhold, Dirk; Schild, Lorenz

    2016-08-01

    Challenge of the immune system with antigens induces a cascade of processes including activation of naïve T cells, induction of proliferation, differentiation into effector cells and finally contraction via apoptosis. To meet the dynamic requirements of an adequate immune response, T cells must metabolically adapt to actual situations by switching between catabolic and anabolic metabolism. In this context mitochondria are hubs of metabolic regulation. The phospholipid cardiolipin (CL) is crucial for the structural and functional integrity and, thus, the metabolism of mitochondria. The aim of this study was to verify a possible interrelationship between T cell proliferation and CL composition. For this purpose, we adjusted the proliferation of peripheral human T cells from volunteers by stimulation with different concentrations of the mitogen phytohaemagglutinin (PHA), inhibition with Cyclosporin A (CsA) and exposure of cells to different free fatty acids and subsequently analysed the composition of CL by LC/MS/MS spectroscopy. All of the treatments had significant effects on CL composition. Correlation analysis of the proliferation rate and CL composition revealed that only the amount of incorporated palmitoleic acid and the content of tetralinoleoyl-CL are significantly associated with the proliferation rate. This observation is strongly suggestive of a regulatory function of these particular CL components/species in the process of T cell proliferation. As CL is crucially involved in mitochondrial function one can speculate that changes in CL composition contribute to vital mitochondria-dependent adaptations of energy metabolism in T cells during immune response. PMID:27163692

  12. Cyclosporine preserves the anergic state of human T cells induced by costimulation blockade in vitro.

    NARCIS (Netherlands)

    Koenen, H.J.P.M.; Fasse, E.; Joosten, I.

    2005-01-01

    BACKGROUND: Costimulation blockade based tolerance-inducing therapies might be disrupted by adjunct conventional immunosuppressive drug use. In the current study, we evaluated the compatibility of various immunosuppressive agents on costimulation blockade-based immunosuppression and T-cell anergy in

  13. Annexin A6 regulates interleukin-2-mediated T-cell proliferation.

    Science.gov (United States)

    Cornely, Rhea; Pollock, Abigail H; Rentero, Carles; Norris, Sarah E; Alvarez-Guaita, Anna; Grewal, Thomas; Mitchell, Todd; Enrich, Carlos; Moss, Stephen E; Parton, Robert G; Rossy, Jérémie; Gaus, Katharina

    2016-07-01

    Annexin A6 (AnxA6) has been implicated in cell signalling by contributing to the organisation of the plasma membrane. Here we examined whether AnxA6 regulates signalling and proliferation in T cells. We used a contact hypersensitivity model to immune challenge wild-type (WT) and AnxA6(-/-) mice and found that the in vivo proliferation of CD4(+) T cells, but not CD8(+) T cells, was impaired in AnxA6(-/-) relative to WT mice. However, T-cell migration and signalling through the T-cell receptor ex vivo was similar between T cells isolated from AnxA6(-/-) and WT mice. In contrast, interleukin-2 (IL-2) signalling was reduced in AnxA6(-/-) compared with WT T cells. Further, AnxA6-deficient T cells had reduced membrane order and cholesterol levels. Taken together, our data suggest that AnxA6 regulates IL-2 homeostasis and sensitivity in T cells by sustaining a lipid raft-like membrane environment. PMID:26853809

  14. In CD4+ T-Cell-Induced Diabetes, Macrophages Are the Final Effector Cells that Mediate Islet β-Cell Killing : Studies from an Acute Model

    OpenAIRE

    Calderon, Boris; Suri, Anish; Unanue, Emil R.

    2006-01-01

    To understand better how diabetogenic CD4+ T cells induce islet β-cell death and cause diabetes, a transfer model of acute diabetes using the diabetogenic CD4+ BDC2.5 T-cell clone was established. Transfer of activated BDC T cells into NOD.scid mice resulted in diabetes within a week, characterized by strong inflammatory reaction. Electron micrographs of pancreas depicted macrophages in close contact with β cells that exhibited signs of apoptosis. Transfer into irradiated recipients inhibited...

  15. Assessment of Newcastle Disease specific T cell proliferation in different inbred MHC chicken lines

    DEFF Research Database (Denmark)

    Norup, Liselotte Rothmann; Dalgaard, Tina Sørensen; Pedersen, Asger Roer;

    2011-01-01

    In this study we have described the establishment of an antigen-specific T cell proliferation assay based on recall stimulation with Newcastle disease (ND) antigen; further, we have described the results obtained after recall stimulation of animals containing different Major Histocompatibility...... Complex (MHC) haplotypes, vaccinated against ND. First optimization of the assay was performed to lower unspecific proliferation and to enhance antigen-specific T cell proliferation. These two issues were achieved using ethylene diamine tetra acetic-acid as stabilizing agent in blood samples......201 chickens were medium in CD4+ or CD8+ T cell responses. High responses were seen only in few animals of each haplotype and not in general. A polymorphism in the chicken CD8 gene was found in our experimental chicken lines, resulting in incapability to detect CD8+ T cells using antibodies from...

  16. Detection of Avian Antigen-Specific T Cells Induced by Viral Vaccines

    DEFF Research Database (Denmark)

    Dalgaard, Tina Sørensen; Norup, Liselotte Rothmann; Juul-Madsen, Helle Risdahl

    2016-01-01

    Live attenuated viral vaccines are widely used in commercial poultry production, but the development of new effective inactivated/subunit vaccines is needed. Studies of avian antigen-specific T cells are primarily based on analyses ex vivo after activating the cells with recall antigen. There is ......Live attenuated viral vaccines are widely used in commercial poultry production, but the development of new effective inactivated/subunit vaccines is needed. Studies of avian antigen-specific T cells are primarily based on analyses ex vivo after activating the cells with recall antigen...... in the cells even throughout division. This leads to daughter cells containing half the fluorescence of their parents. When lymphocytes are loaded with CFSE prior to ex vivo stimulation with specific antigen, the measurement of serial halving of its fluorescence by flow cytometry identifies the cells...

  17. Alterations in regulatory T cells induced by specific oligosaccharides improve vaccine responsiveness in mice.

    Directory of Open Access Journals (Sweden)

    Marcel A Schijf

    Full Text Available Prophylactic vaccinations are generally performed to protect naïve individuals with or without suppressed immune responsiveness. In a mouse model for Influenza vaccinations the specific alterations of CD4(+CD25(+Foxp3(+ regulatory T-cells (Tregs in the immune modulation induced by orally supplied oligosaccharides containing scGOS/lcFOS/pAOS was assessed. This dietary intervention increased vaccine specific DTH responses. In addition, a significant increased percentage of T-bet(+ (Th1 activated CD69(+CD4(+ T cells (p<0.001 and reduced percentage of Gata-3(+ (Th2 activated CD69(+CD4(+T cells (p<0.001 was detected in the mesenteric lymph nodes (MLN of mice receiving scGOS/lcFOS/pAOS compared to control mice. Although no difference in the number or percentage of Tregs (CD4(+Foxp3(+ could be determined after scGOS/lcFOS/pAOS intervention, the percentage of CXCR3 (+ /T-bet(+ (Th1-Tregs was significantly reduced (p<0.05 in mice receiving scGOS/lcFOS/pAOS as compared to mice receiving placebo diets. Moreover, although no absolute difference in suppressive capacity could be detected, an alteration in cytokine profile suggests a regulatory T cell shift towards a reducing Th1 suppression profile, supporting an improved vaccination response.These data are indicative for improved vaccine responsiveness due to reduced Th1 suppressive capacity in the Treg population of mice fed the oligosaccharide specific diet, showing compartmentalization within the Treg population. The modulation of Tregs to control immune responses provides an additional arm of intervention using alternative strategies possibly leading to the development of improved vaccines.

  18. Fgf9 from dermal γδ T cells induces hair follicle neogenesis after wounding.

    Science.gov (United States)

    Gay, Denise; Kwon, Ohsang; Zhang, Zhikun; Spata, Michelle; Plikus, Maksim V; Holler, Phillip D; Ito, Mayumi; Yang, Zaixin; Treffeisen, Elsa; Kim, Chang D; Nace, Arben; Zhang, Xiaohong; Baratono, Sheena; Wang, Fen; Ornitz, David M; Millar, Sarah E; Cotsarelis, George

    2013-07-01

    Understanding molecular mechanisms for regeneration of hair follicles provides new opportunities for developing treatments for hair loss and other skin disorders. Here we show that fibroblast growth factor 9 (Fgf9), initially secreted by γδ T cells, modulates hair follicle regeneration after wounding the skin of adult mice. Reducing Fgf9 expression decreases this wound-induced hair neogenesis (WIHN). Conversely, overexpression of Fgf9 results in a two- to threefold increase in the number of neogenic hair follicles. We found that Fgf9 from γδ T cells triggers Wnt expression and subsequent Wnt activation in wound fibroblasts. Through a unique feedback mechanism, activated fibroblasts then express Fgf9, thus amplifying Wnt activity throughout the wound dermis during a crucial phase of skin regeneration. Notably, humans lack a robust population of resident dermal γδ T cells, potentially explaining their inability to regenerate hair after wounding. These findings highlight the essential relationship between the immune system and tissue regeneration. The importance of Fgf9 in hair follicle regeneration suggests that it could be used therapeutically in humans. PMID:23727932

  19. 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.

  20. Alveolar epithelial type II cells induce T cell tolerance to specific antigen

    DEFF Research Database (Denmark)

    Lo, Bernice; Hansen, Søren; Evans, Kathy;

    2008-01-01

    The lungs face the immunologic challenge of rapidly eliminating inhaled pathogens while maintaining tolerance to innocuous Ags. A break in this immune homeostasis may result in pulmonary inflammatory diseases, such as allergies or asthma. The observation that alveolar epithelial type II cells (Type...... II) constitutively express the class II MHC led us to hypothesize that Type II cells play a role in the adaptive immune response. Because Type II cells do not express detectable levels of the costimulatory molecules CD80 and CD86, we propose that Type II cells suppress activation of naive T cells...

  1. Coimmunization with IL-15 plasmid enhances the longevity of CD8 T cells induced by DNA encoding hepatitis B virus core antigen

    Institute of Scientific and Technical Information of China (English)

    Wei Zhang; Sheng-Fu Dong; Shu-Hui Sun; Yuan Wang; Guang-Di Li; Di Qu

    2006-01-01

    AIM: To test the feasibility of delivering a plasmid encoding IL-15 as a DNA vaccine adjuvant for improving the immune responses induced by hepatitis B virus core gene DNA vaccine.METHODS: We used RT-PCR based strategies to develop IL-15 expression constructs. We first confirmed that the gene could be expressed in Escherichia coli due to the poor expression of IL-15. Then the bioactivity of IL-15 plasmid expression product was identified by CTLL-2 proliferation assay. One hundred micrograms of DNA from each of the IL-15 eukaryotic expressed plasmid and the recombinant plasmid harboring DNA encoding the 144 amino acids of the N-terminus of HBV core gene (abbreviated pHBc144) was used to co-immunize C57 BL/6 mice. The titer of anti-HBcIgG was detected by ELISA and the antigen-specific CD8+T cells (CD8+IFN-γ+ T cells) were detected by intracellular cytokine staining at different time points.RESULTS: After co-immunization by pIL-15 and pHBc144 DNA vaccine the antigen-specific CD8+ cells of mice increased gradually, the first peak of immune response appeared 14 d later, then the number of antigen-specific CD8+ Ts cells decreased gradually and maintained at a steady level in 3 mo. After boosting, the number of antigen-specific CD8+ T cells reached the second peak 10 d later with a double of the 1st peak, then the number of antigen-specific CD8+T cells decreased slowly. IL-15 as a gene adjuvant had no significant effect on humoral immune responses induced by hepatitis B virus core gene DNA vaccine, but increased the memory antigen-specific CD8+ T cells induced by hepatitis B virus core gene DNA vaccine.CONCLUSION: DNA vaccine constructed by HBc Ag 1-144 amino acid induces effective cell immunity, and cytokine plasmid-delivered IL-15 enhances the longevity of CD8+ T cells.

  2. Immunization with adenovirus LIGHT-engineered dendritic cells induces potent T cell responses and therapeutic immunity in HBV transgenic mice.

    Science.gov (United States)

    Jiang, Wenzheng; Chen, Ran; Kong, Xiaobo; Long, Fengying; Shi, Yaru

    2014-07-31

    LIGHT, a TNF superfamily member (TNFSF14), is a type II transmembrane protein expressed on activated T cells and immature dendritic cells (DCs). However, the expression of LIGHT on mature DCs is down-regulated. Recent studies demonstrated that LIGHT provides potent costimulatory activity for T cells, enhancing proliferation and the production of Th1 cytokines independently of the B7-CD28 pathway. Here, we evaluated the effectiveness of peptide-pulsed DC-mediated antiviral immunity in HBV transgenic mice and the immunoadjuvant effect of LIGHT. The bone marrow-derived DCs were modified in vitro with an adenovirus (Ad) vector expressing mouse LIGHT (Ad-LIGHT), the expression of costimulatory molecules was up-regulated and the secretion of cytokines IL-12 and IFN-γ increased. LIGHT-modified DCs enhanced allostimulation for T cells in mixed lymphocyte reaction (MLR). HBV peptide-pulsed DCs elicited HBV specific CD8+ T cell response and reduced the level of HBsAg and HBV DNA in sera of HBV transgenic mice. Importantly, LIGHT-modified DCs could induce stronger antiviral immunity. These results support the concept that genetic modification of DCs with a recombinant LIGHT adenovirus vector may be a useful strategy for antiviral immunotherapy. PMID:24951859

  3. Surfactant Protein A integrates activation signal strength to differentially modulate T cell proliferation

    OpenAIRE

    Mukherjee, Sambuddho; Giamberardino, Charles; Thomas, Joseph; Evans, Kathy; GOTO, HISATSUGU; Ledford, Julie G.; Hsia, Bethany; Pastva, Amy M.; Wright, Jo Rae

    2012-01-01

    Pulmonary surfactant lipoproteins lower the surface tension at the alveolar:airway interface of the lung and participate in host defense. Previous studies reported that surfactant protein A (SP-A) inhibits lymphocyte proliferation. We hypothesized that SP-A mediated modulation of T cell activation depends upon the strength, duration and type of lymphocyte activating signals. Modulation of T cell signal strength imparted by different activating agents ex and in vivo in different mouse models, ...

  4. Memory-Like CD8+ T Cells Generated during Homeostatic Proliferation Defer to Antigen-Experienced Memory Cells1

    OpenAIRE

    Cheung, Kitty P.; Yang, Edward; Goldrath, Ananda W

    2009-01-01

    Naive T cells proliferate in response to lymphopenia and acquire the phenotypic and functional qualities of memory T cells, providing enhanced protection against infection. How well memory-like T cells generated during lymphopenia-induced homeostatic proliferation (HP)-memory differentiate into secondary memory cells and compete with Ag-experienced true-memory cells is unknown. We found that CD8+ HP-memory T cells generated robust responses upon infection and produced a secondary memory popul...

  5. Dendritic cells fused with different pancreatic carcinoma cells induce different T-cell responses

    Directory of Open Access Journals (Sweden)

    Andoh Y

    2013-01-01

    Full Text Available Yoshiaki Andoh,1,2 Naohiko Makino,2 Mitsunori Yamakawa11Department of Pathological Diagnostics, 2Department of Gastroenterology, Yamagata University School of Medicine, Yamagata, JapanBackground: It is unclear whether there are any differences in the induction of cytotoxic T lymphocytes (CTL and CD4+CD25high regulatory T-cells (Tregs among dendritic cells (DCs fused with different pancreatic carcinomas. The aim of this study was to compare the ability to induce cytotoxicity by human DCs fused with different human pancreatic carcinoma cell lines and to elucidate the causes of variable cytotoxicity among cell lines.Methods: Monocyte-derived DCs, which were generated from peripheral blood mononuclear cells (PBMCs, were fused with carcinoma cells such as Panc-1, KP-1NL, QGP-1, and KP-3L. The induction of CTL and Tregs, and cytokine profile of PBMCs stimulated by fused DCs were evaluated.Results: The cytotoxicity against tumor targets induced by PBMCs cocultured with DCs fused with QGP-1 (DC/QGP-1 was very low, even though PBMCs cocultured with DCs fused with other cell lines induced significant cytotoxicity against the respective tumor target. The factors causing this low cytotoxicity were subsequently investigated. DC/QGP-1 induced a significant expansion of Tregs in cocultured PBMCs compared with DC/KP-3L. The level of interleukin-10 secreted in the supernatants of PBMCs cocultured with DC/QGP-1 was increased significantly compared with that in DC/KP-3L. Downregulation of major histocompatibility complex class I expression and increased secretion of vascular endothelial growth factor were observed with QGP-1, as well as in the other cell lines.Conclusion: The present study demonstrated that the cytotoxicity induced by DCs fused with pancreatic cancer cell lines was different between each cell line, and that the reduced cytotoxicity of DC/QGP-1 might be related to the increased secretion of interleukin-10 and the extensive induction of Tregs

  6. REDD1 Is Essential for Optimal T Cell Proliferation and Survival.

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    Emma L Reuschel

    Full Text Available REDD1 is a highly conserved stress response protein that is upregulated following many types of cellular stress, including hypoxia, DNA damage, energy stress, ER stress, and nutrient deprivation. Recently, REDD1 was shown to be involved in dexamethasone induced autophagy in murine thymocytes. However, we know little of REDD1's function in mature T cells. Here we show for the first time that REDD1 is upregulated following T cell stimulation with PHA or CD3/CD28 beads. REDD1 knockout T cells exhibit a defect in proliferation and cell survival, although markers of activation appear normal. These findings demonstrate a previously unappreciated role for REDD1 in T cell function.

  7. 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.

  8. IL-9 production by regulatory T cells recruits mast cells that are essential for regulatory T cell-induced immune suppression.

    Science.gov (United States)

    Eller, Kathrin; Wolf, Dominik; Huber, Julia M; Metz, Martin; Mayer, Gert; McKenzie, Andrew N J; Maurer, Marcus; Rosenkranz, Alexander R; Wolf, Anna M

    2011-01-01

    Both mast cells (MCs) and regulatory T cells (Tregs) have gained attention as immunosuppressive cell populations. To investigate a possible interaction, we used the Th1- and Th17-dependent model of nephrotoxic serum nephritis (NTS), in which both MCs and Tregs have been shown to play a protective role. Transfer of wild-type (wt) Tregs into wt recipients almost completely prevents development of NTS and leads to a profound increase of MCs in the renal draining lymph nodes (LNs). By contrast, transfer of wt Tregs into animals deficient in MCs, which are characterized by an exaggerated susceptibility to NTS, no longer exhibited protective effects. Blocking the pleiotropic cytokine IL-9, known to be involved in MC recruitment and proliferation, by means of a mAb in mice receiving Tregs abrogated protection from NTS. Moreover, transfer of IL-9-deficient Tregs also failed to protect from NTS. In the absence of Treg-derived IL-9, MCs fail to accumulate in the LNs, despite the fact that IL-9 deficiency does not alter the general suppressive activity of Tregs. In summary, to our knowledge, we provide the first direct in vivo evidence that the nephroprotective, anti-inflammatory effects of Tregs critically depend on IL-9-mediated attraction of MCs into kidney-draining LNs. PMID:21115728

  9. 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.

  10. Regulatory T Cells Accumulate in the Lung Allergic Inflammation and Efficiently Suppress T-Cell Proliferation but Not Th2 Cytokine Production

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    Lucas Faustino

    2012-01-01

    Full Text Available Foxp3+CD25+CD4+ regulatory T cells are vital for peripheral tolerance and control of tissue inflammation. In this study, we characterized the phenotype and monitored the migration and activity of regulatory T cells present in the airways of allergic or tolerant mice after allergen challenge. To induce lung allergic inflammation, mice were sensitized twice with ovalbumin/aluminum hydroxide gel and challenged twice with intranasal ovalbumin. Tolerance was induced by oral administration of ovalbumin for 5 consecutive days prior to OVA sensitization and challenge. We detected regulatory T cells (Foxp3+CD25+CD4+ T cells in the airways of allergic and tolerant mice; however, the number of regulatory T cells was more than 40-fold higher in allergic mice than in tolerant mice. Lung regulatory T cells expressed an effector/memory phenotype (CCR4highCD62LlowCD44highCD54highCD69+ that distinguished them from naive regulatory T cells (CCR4intCD62LhighCD44intCD54intCD69−. These regulatory T cells efficiently suppressed pulmonary T-cell proliferation but not Th2 cytokine production.

  11. Human adipose-tissue derived mesenchymal stem cells induce functional de-novo regulatory T cells with methylated FOXP3 gene DNA

    NARCIS (Netherlands)

    Engela, A. U.; Hoogduijn, M. J.; Boer, K.; Litjens, N. H. R.; Betjes, M. G. H.; Weimar, W.; Baan, C. C.

    2013-01-01

    Due to their immunomodulatory properties, mesenchymal stem cells (MSC) are interesting candidates for cellular therapy for autoimmune disorders, graft-versus-host disease and allograft rejection. MSC inhibit the proliferation of effector T cells and induce T cells with a regulatory phenotype. So far

  12. 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

    T lymphocytes express a plethora of distinct ion channels that participate in the control of calcium homeostasis and signal transduction. Potassium channels play a critical role in the modulation of T cell calcium signaling, and the significance of the voltage-dependent K channel, Kv1.3, is well...... established. The recent cloning of the Ca(2+)-activated, intermediate-conductance K(+) channel (IK channel) has enabled a detailed investigation of the role of this highly Ca(2+)-sensitive K(+) channel in the calcium signaling and subsequent regulation of T cell proliferation. The role IK channels play in T...

  13. 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

    of cutaneous T-cell lymphoma (Sezary syndrome) patients. PDCD10 is associated with protein phosphatase-2A, a regulator of mitogenesis and apoptosis in malignant T cells. Inhibition of oncogenic signal pathways [Jak3, Notch1, and nuclear factor-¿B (NF-¿B)] partly inhibits the constitutive PDCD10 expression......, 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...

  14. Mesenchymal stem cells induce T-cell tolerance and protect the preterm brain after global hypoxia-ischemia.

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    Reint K Jellema

    Full Text Available Hypoxic-ischemic encephalopathy (HIE in preterm infants is a severe disease for which no curative treatment is available. Cerebral inflammation and invasion of activated peripheral immune cells have been shown to play a pivotal role in the etiology of white matter injury, which is the clinical hallmark of HIE in preterm infants. The objective of this study was to assess the neuroprotective and anti-inflammatory effects of intravenously delivered mesenchymal stem cells (MSC in an ovine model of HIE. In this translational animal model, global hypoxia-ischemia (HI was induced in instrumented preterm sheep by transient umbilical cord occlusion, which closely mimics the clinical insult. Intravenous administration of 2 x 10(6 MSC/kg reduced microglial proliferation, diminished loss of oligodendrocytes and reduced demyelination, as determined by histology and Diffusion Tensor Imaging (DTI, in the preterm brain after global HI. These anti-inflammatory and neuroprotective effects of MSC were paralleled by reduced electrographic seizure activity in the ischemic preterm brain. Furthermore, we showed that MSC induced persistent peripheral T-cell tolerance in vivo and reduced invasion of T-cells into the preterm brain following global HI. These findings show in a preclinical animal model that intravenously administered MSC reduced cerebral inflammation, protected against white matter injury and established functional improvement in the preterm brain following global HI. Moreover, we provide evidence that induction of T-cell tolerance by MSC might play an important role in the neuroprotective effects of MSC in HIE. This is the first study to describe a marked neuroprotective effect of MSC in a translational animal model of HIE.

  15. IL-18Rα-deficient CD4+T cells induce intestinal inflammation in the CD45RBhitransfer model of colitis despite impaired innate responsiveness

    DEFF Research Database (Denmark)

    Holmkvist, Petra; Pool, Lieneke; Hägerbrand, Karin;

    2016-01-01

    IL-18 has been implicated in inflammatory bowel disease (IBD), however its role in the regulation of intestinal CD4+ T-cell function remains unclear. Here we show that murine intestinal CD4+ T cells express high levels of IL-18Rα and provide evidence that IL-18Rα expression is induced on these ce......IL-18 has been implicated in inflammatory bowel disease (IBD), however its role in the regulation of intestinal CD4+ T-cell function remains unclear. Here we show that murine intestinal CD4+ T cells express high levels of IL-18Rα and provide evidence that IL-18Rα expression is induced...... on these cells subsequent to their entry into the intestinal mucosa. Using the CD45RBhi T-cell transfer colitis model, we show that IL-18Rα is expressed on IFN-γ+, IL-17+ and IL-17+IFN-γ+ effector CD4+ T cells in the inflamed colonic lamina propria (cLP) and mesenteric lymph node (MLN) and is required...... for the optimal generation and/or maintenance of IFN-γ-producing cells in the cLP. In the steady state and during colitis, TCR-independent cytokine-induced IFN-γ and IL-17 production by intestinal CD4+ T cells was largely IL-18Rα−dependent. Despite these findings however, IL-18Rα−deficient CD4+ T cells induced...

  16. 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.

  17. Human Liver Stem Cells Suppress T-Cell Proliferation, NK Activity, and Dendritic Cell Differentiation

    OpenAIRE

    Stefania Bruno; Cristina Grange; Marta Tapparo; Chiara Pasquino; Renato Romagnoli; Ennia Dametto; Antonio Amoroso; Ciro Tetta; Giovanni Camussi

    2016-01-01

    Human liver stem cells (HLSCs) are a mesenchymal stromal cell-like population resident in the adult liver. Preclinical studies indicate that HLSCs could be a good candidate for cell therapy. The aim of the present study was to evaluate the immunogenicity and the immunomodulatory properties of HLSCs on T-lymphocytes, natural killer cells (NKs), and dendritic cells (DCs) in allogeneic experimental settings. We found that HLSCs inhibited T-cell proliferation by a mechanism independent of cell co...

  18. Human Liver Stem Cells Suppress T-Cell Proliferation, NK Activity, and Dendritic Cell Differentiation

    Directory of Open Access Journals (Sweden)

    Stefania Bruno

    2016-01-01

    Full Text Available Human liver stem cells (HLSCs are a mesenchymal stromal cell-like population resident in the adult liver. Preclinical studies indicate that HLSCs could be a good candidate for cell therapy. The aim of the present study was to evaluate the immunogenicity and the immunomodulatory properties of HLSCs on T-lymphocytes, natural killer cells (NKs, and dendritic cells (DCs in allogeneic experimental settings. We found that HLSCs inhibited T-cell proliferation by a mechanism independent of cell contact and dependent on the release of prostaglandin E2 (PGE2 and on indoleamine 2,3-dioxygenase activity. When compared with mesenchymal stromal cells (MSCs, HLSCs were more efficient in inhibiting T-cell proliferation. At variance with MSCs, HLSCs did not elicit NK degranulation. Moreover, HLSCs inhibited NK degranulation against K562, a NK-sensitive target, by a mechanism dependent on HLA-G release. When tested on DC generation from monocytes, HLSCs were found to impair DC differentiation and DCs ability to induce T-cell proliferation through PGE2. This study shows that HLSCs have immunomodulatory properties similar to MSCs, but, at variance with MSCs, they do not elicit a NK response.

  19. Genome-wide RNA profiling of long-lasting stem cell-like memory CD8 T cells induced by Yellow Fever vaccination in humans

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    Silvia A. Fuertes Marraco

    2015-09-01

    Full Text Available The live-attenuated Yellow Fever (YF vaccine YF-17D induces a broad and polyfunctional CD8 T cell response in humans. Recently, we identified a population of stem cell-like memory CD8 T cells induced by YF-17D that persists at stable frequency for at least 25 years after vaccination. The YF-17D is thus a model system of human CD8 T cell biology that furthermore allows to track and study long-lasting and antigen-specific human memory CD8 T cells. Here, we describe in detail the sample characteristics and preparation of a microarray dataset acquired for genome-wide gene expression profiling of long-lasting YF-specific stem cell-like memory CD8 T cells, compared to the reference CD8 T cell differentiation subsets from total CD8 T cells. We also describe the quality controls, annotations and exploratory analyses of the dataset. The microarray data is available from the Gene Expression Omnibus (GEO public repository with accession number GSE65804.

  20. Genome-wide RNA profiling of long-lasting stem cell-like memory CD8 T cells induced by Yellow Fever vaccination in humans.

    Science.gov (United States)

    Fuertes Marraco, Silvia A; Soneson, Charlotte; Delorenzi, Mauro; Speiser, Daniel E

    2015-09-01

    The live-attenuated Yellow Fever (YF) vaccine YF-17D induces a broad and polyfunctional CD8 T cell response in humans. Recently, we identified a population of stem cell-like memory CD8 T cells induced by YF-17D that persists at stable frequency for at least 25 years after vaccination. The YF-17D is thus a model system of human CD8 T cell biology that furthermore allows to track and study long-lasting and antigen-specific human memory CD8 T cells. Here, we describe in detail the sample characteristics and preparation of a microarray dataset acquired for genome-wide gene expression profiling of long-lasting YF-specific stem cell-like memory CD8 T cells, compared to the reference CD8 T cell differentiation subsets from total CD8 T cells. We also describe the quality controls, annotations and exploratory analyses of the dataset. The microarray data is available from the Gene Expression Omnibus (GEO) public repository with accession number GSE65804. PMID:26484272

  1. Elevated Apoptosis and Impaired Proliferation Contribute to Downregulated Peripheral γδ T Cells in Patients with Systemic Lupus Erythematosus

    Directory of Open Access Journals (Sweden)

    Zhimin Lu

    2013-01-01

    Full Text Available Objective. To investigate the frequency of peripheral γδ T cells in patients with systemic lupus erythematosus (SLE and its correlation with disease activity and to analyze the apoptotic status, proliferation ability, and intracellular cytokine profile of these cells. Methods. Flow cytometry was performed to detect the percentage and intracellular cytokine expression of peripheral γδ T cells from SLE patients. Annexin-V/PI double staining was applied to determine the proportion of apoptotic γδ and CD3+ T cells. γδ T cell proliferation was analyzed by CFSE labeling technique. Results. The percentage and absolute number of γδ T cells were remarkably decreased in active SLE patients compared to those in inactive patients and healthy controls, with γδ T cell count negatively correlated with disease activity. Compared with healthy controls, peripheral γδ T cells from active SLE patients exhibited higher apoptotic rate and lower proliferation ability, as well as elevated expression of intracellular IFN-γ, IL-4, IL-10, and TGF-β, but not IL-17 or Foxp3. Conclusion. Decreased γδ T cells in the peripheral blood of SLE patients might be caused by upregulated apoptosis and downregulated cell proliferation. These γδ T cells may secret both pro- and anti-inflammatory cytokines to perform their functions in SLE.

  2. IL-9 production by regulatory T cells recruits mast cells that are essential for regulatory T cell-induced immune-suppression

    OpenAIRE

    Eller, Kathrin; Wolf, Dominik; Huber, Julia M; Metz, Martin; Mayer, Gert; McKenzie, Andrew N.J.; Maurer, Marcus; Rosenkranz, Alexander R.; Wolf, Anna M

    2010-01-01

    Both, mast cells (MC) and regulatory T cells (Treg) have gained attention as immunosuppressive cell populations. To investigate a possible interaction, we used the Th1- and Th17-dependent model of nephrotoxic serum nephritis (NTS), in which both MC and Treg have been shown to play a protective role.

  3. Proliferation of CD8-positive T cells in blood vessels of rat renal allografts.

    Science.gov (United States)

    Grau, V; Fuchs-Moll, G; Wilker, S; Weimer, R; Padberg, W

    2011-09-01

    It is still disputed in which anatomical compartments of allograft recipients T-cells proliferate. After experimental renal transplantation, host monocytes and lymphocytes accumulate in the lumina of graft blood vessels. In this study, we test the hypothesis that T lymphocytes proliferate in the vascular bed of the graft. Kidneys were transplanted in the Dark Agouti to Lewis rat strain combination, an established experimental model for acute rejection. Isogeneic transplantation was performed as a control. Cells in the S-phase of mitosis were detected in situ three days posttransplantation by pulse-labeling with BrdU and by immunohistochemical detection of the proliferating cell nuclear antigen (PCNA). More than 20% of all T-cells in the lumina of allograft blood vessels incorporated BrdU and approximately 30% of them expressed PCNA. In the blood vessels of isografts as well as in other organs of allograft recipients, only few BrdU(+) cells were detected. A majority of the BrdU(+) cells in graft blood vessels expressed CD8. In conclusion, we demonstrate that CD8(+) T lymphocytes proliferate in the lumina of the blood vessels of renal allografts during the onset of acute rejection.

  4. Freeze-thaw lysates of Plasmodium falciparum-infected red blood cells induce differentiation of functionally competent regulatory T cells from memory T cells

    OpenAIRE

    Finney, Olivia C; Lawrence, Emma; Gray, Alice P; Njie, Madi; Riley, Eleanor M.; Walther, Michael

    2012-01-01

    In addition to naturally occurring regulatory T (nTreg) cells derived from the thymus, functionally competent Treg cells can be induced in vitro from peripheral blood lymphocytes in response to TCR stimulation with cytokine costimulation. Using these artificial stimulation conditions, both naïve as well as memory CD4+ T cells can be converted into induced Treg (iTreg) cells, but the cellular origin of such iTreg cells in vivo or in response to more physiologic stimulation with pathogen-derive...

  5. Characterization of T-regulatory cells, induced by immature dendritic cells, which inhibit enteroantigen-reactive colitis-inducing T-cell responses in vitro and in vivo

    DEFF Research Database (Denmark)

    Gad, Monika; Kristensen, Nanna N; Kury, Evelyn;

    2004-01-01

    Regulatory T (Treg) cells, derived from co-cultures of unfractionated CD4(+) T cells and immature dendritic cells (DC), suppress enteroantigen-induced proliferation of CD4(+) CD25(-) T cells. The DC-induced Treg cells are a mixture of CD25(+) (10-20%) and CD25(-) (80-90%) T cells. However, all the...... suppressor activity in vitro and in vivo resides in the CD25(+) T-cell subset. The CD25(+) DC-induced Treg cells can inhibit enteroantigen-induced proliferation in vitro through a transwell membrane, and their function does not appear to depend on previous activation. DC-induced CD25(+) Treg cells display a...... naive phenotype, expressing high levels of CD45RB and l-selectin (CD62L). In addition, the DC-induced Treg cells mediate a stronger suppressive activity than prototype CD25(+) regulatory T cells. The DC-induced Treg cells, and hereof purified CD25(+) and CD25(-) T-cell fractions, were co-injected into...

  6. 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

    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......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...... 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...

  7. Ethanol suppresses T cell proliferation without inhibiting interleukin 2 (IL2) production and IL2 receptor (IL2R) expression

    Energy Technology Data Exchange (ETDEWEB)

    Chang, M.P.; Norman, D.C. (VA Medical Center, West Los Angeles, CA (United States) Univ. of California, Los Angeles (United States))

    1991-03-11

    The effect of extended ethanol consumption of young C57BL/6J mice on T cell proliferation was studied. Splenic cells of young mice, fed with one of three different liquid diets for 6-7 weeks were cultured with Con A to assess T cell proliferation and production of IL2. Then, the proliferative response of splenic cells to PMA/ionomycin was assessed. Finally, Con A-activated T blast cells were assessed for their ability to express IL2R and to respond to IL2. The results showed that both Con A-induced mitogenesis and IL2-dependent proliferation of T cells from ethanol diet-fed mice were diminished as compared to that of maltose-substitute diet or standard liquid diet. However, the ability of T cells from ethanol diet-fed mice to produce IL2 and to express IL2R was not affected. Furthermore, the magnitude of ethanol-mediated suppression of T cell proliferation induced by PMA/ionomycin was comparable to that induced by Con A. These results taken together suggest that ethanol suppresses T cell proliferation by interfering with events following the IL2-IL2R interaction.

  8. Reactive oxygen species-dependent necroptosis in Jurkat T cells induced by pathogenic free-living Naegleria fowleri.

    Science.gov (United States)

    Song, K-J; Jang, Y S; Lee, Y A; Kim, K A; Lee, S K; Shin, M H

    2011-07-01

    Naegleria fowleri, a free-living amoeba, is the causative pathogen of primary amoebic meningoencephalitis in humans and experimental mice. N. fowleri is capable of destroying tissues and host cells through lytic necrosis. However, the mechanism by which N. fowleri induces host cell death is unknown. Electron microscopy indicated that incubation of Jurkat T cells with N. fowleri trophozoites induced necrotic morphology of the Jurkat T cells. N. fowleri also induced cytoskeletal protein cleavage, extensive poly (ADP-ribose) polymerase hydrolysis and lactate dehydrogenase (LDH) release. Although no activation of caspase-3 was observed in Jurkat T cells co-incubated with amoebae, intracellular reactive oxygen species (ROS) were strongly generated by NADPH oxidase (NOX). Pretreating cells with necroptosis inhibitor necrostatin-1 or NOX inhibitor diphenyleneiodonium chloride (DPI) strongly inhibited amoeba-induced ROS generation and Jurkat cell death, whereas pan-caspase inhibitor z-VAD-fmk did not. N. fowleri-derived secretory products (NfSP) strongly induced intracellular ROS generation and cell death. Necroptotic effects of NfSP were effectively inhibited by pretreating NfSP with proteinase K. Moreover, NfSP-induced LDH release and intracellular ROS accumulation were inhibited by pretreating Jurkat T cells with DPI or necrostatin-1. These results suggest that N. fowleri induces ROS-dependent necroptosis in Jurkat T cells.

  9. Semiallogenic fusions of MSI+ tumor cells and activated B cells induce MSI-specific T cell responses

    Directory of Open Access Journals (Sweden)

    Klier Ulrike

    2011-09-01

    Full Text Available Abstract Background Various strategies have been developed to transfer tumor-specific antigens into antigen presenting cells in order to induce cytotoxic T cell responses against tumor cells. One approach uses cellular vaccines based on fusions of autologous antigen presenting cells and allogeneic tumor cells. The fusion cells combine antigenicity of the tumor cell with optimal immunostimulatory capacity of the antigen presenting cells. Microsatellite instability caused by mutational inactivation of DNA mismatch repair genes results in translational frameshifts when affecting coding regions. It has been shown by us and others that these mutant proteins lead to the presentation of immunogenic frameshift peptides that are - in principle - recognized by a multiplicity of effector T cells. Methods We chose microsatellite instability-induced frameshift antigens as ideal to test for induction of tumor specific T cell responses by semiallogenic fusions of microsatellite instable carcinoma cells with CD40-activated B cells. Two fusion clones of HCT116 with activated B cells were selected for stimulation of T cells autologous to the B cell fusion partner. Outgrowing T cells were phenotyped and tested in functional assays. Results The fusion clones expressed frameshift antigens as well as high amounts of MHC and costimulatory molecules. Autologous T cells stimulated with these fusions were predominantly CD4+, activated, and reacted specifically against the fusion clones and also against the tumor cell fusion partner. Interestingly, a response toward 6 frameshift-derived peptides (of 14 tested could be observed. Conclusion Cellular fusions of MSI+ carcinoma cells and activated B cells combine the antigen-presenting capacity of the B cell with the antigenic repertoire of the carcinoma cell. They present frameshift-derived peptides and can induce specific and fully functional T cells recognizing not only fusion cells but also the carcinoma cells. These

  10. Immunological features of T cells induced by human telomerase reverse transcriptase-derived peptides in patients with hepatocellular carcinoma.

    Science.gov (United States)

    Mizukoshi, Eishiro; Nakagawa, Hidetoshi; Kitahara, Masaaki; Yamashita, Tatsuya; Arai, Kuniaki; Sunagozaka, Hajime; Fushimi, Kazumi; Kobayashi, Eiji; Kishi, Hiroyuki; Muraguchi, Atsushi; Kaneko, Shuichi

    2015-08-10

    Human telomerase reverse transcriptase (hTERT) is a catalytic enzyme required for telomere elongation. In this study, we investigated the safety and immunogenicity of an hTERT-derived peptide (hTERT461) as a vaccine and characterized the hTERT-specific T cell responses induced. Fourteen hepatocellular carcinoma (HCC) patients were enrolled in the study. The hTERT-derived peptide was emulsified in incomplete Freund's adjuvant and administered via subcutaneous immunization three times biweekly. The maximum toxicity observed was grade 2 according to the common terminology criteria and mainly consisted of skin reactions at the site of vaccination. The vaccination induced hTERT-specific immunity in 71.4% of patients and 57.1% of patients administered with hTERT461 peptide-specific T cells could prevent HCC recurrence after vaccination. In phenotypic analysis, the post-vaccinated increase in hTERT-specific T cells was due to an increase in cells with the effector memory phenotype, with the potential to produce multiple cytokines. Seven hTERT-specific T cell receptors were obtained from the vaccinated patients, showing their cytotoxic activities to hTERT-derived peptide-bearing cells. In conclusion, the safety and effects of immune boosting by hTERT461 peptide have shown the potential of the peptide to provide clinical benefits in HCC patients. PMID:25982205

  11. Shock Waves Increase T-cell Proliferation or IL-2 Expression by Activating p38 MAP Kinase

    Institute of Scientific and Technical Information of China (English)

    Tie-Cheng YU; Yi LIU; Yan TAN; Yanfang JIANG; Xueqing ZHENG; Xinxiang XU

    2004-01-01

    Shock waves were elicited by transient pressure disturbances, which could be used to treat musculoskeletal disorders. In present studies, we i. nvestigated whether the low-density shock waves (LDSWs), which are able to damage plasma membrane without impairing the vimentin or other organelles, might augment T-cell proliferation as well as IL-2 expression, and if mitogen activated protein kinase p38 (p38 MAPK)might be an underlying mechanism through which the LDSWs enhanced T-cell function. We found that the LDSWs increased activation of p38 MAPK in Jurkat T cells. The LDSWs alone didn't result in the T-cell proliferation and IL-2 expression. However, in combination with other stimuli, LDSWs could augment the T-cell proliferation and IL-2 expression. Inhibition of p38 MAPK using SB203580 reduced the stimulatory effects of the LDSWs, which indicated that the LDSWs enhanced IL-2 expression through a mechanism that involved p38 MAPK activation. We concluded that the p38 MAPK activation played a key role in the regulation of T cell function by the LDSWs.

  12. 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.

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

    Directory of Open Access Journals (Sweden)

    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.

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

    Science.gov (United States)

    Lee, Young Ah; Kim, Hang-Rae; Lee, Jeong Seon; Jung, Hae Woon; Kim, Hwa Young; Lee, Gyung Min; Lee, Jieun; Sim, Ji Hyun; Oh, Sae Jin; Chung, Doo Hyun; Shin, Choong Ho; Yang, Sei Won

    2015-01-01

    Objective 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. Design and Methods 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. Results 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. Conclusions 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. PMID:26709833

  15. Expression of p13MTCP1 is restricted to mature T-cell proliferations with t(X;14) translocations.

    Science.gov (United States)

    Madani, A; Choukroun, V; Soulier, J; Cacheux, V; Claisse, J F; Valensi, F; Daliphard, S; Cazin, B; Levy, V; Leblond, V; Daniel, M T; Sigaux, F; Stern, M H

    1996-03-01

    T-cell prolymphocytic leukemia (T-PLL), a rare form of mature T-cell leukemias, and ataxia telangiectasia clonal proliferation, a related condition occurring in patients suffering from ataxia telangiectasia, have been associated to translocations involving the 14q32.1 or Xq28 regions, where are located the TCL1 and MTCP1 putative oncogenes, respectively. The MTCP1 gene is involved in the t(X;14)(q28;q11) translocation associated with these T-cell proliferations. Alternative splicing generates type A and B transcripts that potentially encode two entirely distinct proteins; type A transcripts code for a small mitochondrial protein, p8MTCP1, and type B transcripts, containing an additional open reading frame, may code for 107 amino-acid protein, p13MTCP1. The recently cloned TCL1 gene, also involved in translocations and inversions associated with T-cell proliferations, codes for a 14-kD protein that displays significant homology with p13MTCP1. We have generated rabbit antisera against this putative p13MTCP1 protein and screened for expression of p13MTCP1 normal lymphoid tissues and 33 cases of immature and mature lymphoid T-cell proliferations using a sensitive Western blot assay. We also investigated the MTCP1 locus configuration by Southern blot analysis. The p13MTCP1 protein was detected in the three T-cell proliferations with MTCP1 rearrangements because of t(X;14) translocations, but neither in normal resting and activated lymphocytes nor in the other T-cell leukemias. Our data support the hypothesis that p13MTCP1 and p14TCL1 form a new protein family that plays a key role in the pathogenesis of T-PLL and related conditions.

  16. Development of Virus-Specific CD4+ and CD8+ Regulatory T Cells Induced by Human Herpesvirus 6 Infection

    OpenAIRE

    Wang, Fang; Chi, Jing; Peng, Guangyong; Zhou, Feng; Wang, Jinfeng; Li, Lingyun; Feng, Dongju; Xie, Fangyi; Gu, Bin; Qin, Jian; CHEN, YUN; Yao, Kun

    2014-01-01

    Human herpesvirus 6 (HHV-6) is an important immunosuppressive and immunomodulatory virus. The mechanisms by which HHV-6 establishes latency and immunosuppression in its host are not well understood. Here we characterized HHV-6-specific T cells in peripheral blood mononuclear cells (PBMCs) from HHV-6-infected donors. Our results showed that HHV-6 infection could induce both CD4+ and CD8+ HHV-6-specific regulatory T (Treg) cells. These HHV-6-specific Treg cells had potent suppressive activity a...

  17. The Inhibitory Role of Lactacystin and β-Lactacystinon T-cell Activation and Proliferation

    Institute of Scientific and Technical Information of China (English)

    Peng-HongSONG; Hai-YangXIE; Shu-SenZHENG; JianWU

    2004-01-01

    To evaluate the effects of proteasome inhibitors lactacystin (LAC) and β-1actacystin (β-LAC)on the proliferation and activation of T lymphocytes, flow cytometry was used to analyze the proliferationand the expression of CD69, CD25 and CD3 of T lymphocytes activated by PHA. Furthermore, theexpressions of PA28 and IL-2 mRNA were assayed by competitive RT-PCR. The results indicated that:(1) LAC and 13-LAC significantly decreased the incomoration of BrdU and inhibited T lymohocytesoroliferation in T lymphocytes activated by PHA; (2) although LAC and β-LAC did not affect the expressionof CD69 at any time, they significantly inhibited the expression of CD25 (48 h, 72 h, P<0.05);(3) in comoarison with control, LAC and β-LAC significantly down-regulated the expression of PA28and 1L-2 mRNA (48 h, 72 h, P<0.05). LAC and β-LAC significantly inhibited the proliferation and activationof T cells. Mechanisms involved are inhibition of CD25 and down-regulation of PA28 and IL-2 mRNAexpressions.

  18. The Inhibitory Role of Lactacystin and β-Lactacystin on T-cell Activation and Proliferation

    Institute of Scientific and Technical Information of China (English)

    Peng-Hong SONG; Hai-Yang XIE; Shu-Sen ZHENG; Jian WU

    2004-01-01

    To evaluate the effects of proteasome inhibitors lactacystin (LAC) and β-lactacystin (β-LAC)on the proliferation and activation of T lymphocytes, flow cytometry was used to analyze the proliferationand the expression of CD69, CD25 and CD3 of T lymphocytes activated by PHA. Furthermore, theexpressions of PA28 and IL-2 mRNA were assayed by competitive RT-PCR. The results indicated that:(1) LAC and β-LAC significantly decreased the incorporation of BrdU and inhibited T lymphocytesproliferation in T lymphocytes activated by PHA; (2) although LAC and β-LAC did not affect the expressionof CD69 at any time, they significantly inhibited the expression of CD25 (48h, 72h, P<0.05);(3) in comparison with control, LAC and β-LAC significantly down-regulated the expression of PA28and IL-2 mRNA (48h, 72h, P<0.05). LAC and β-LAC significantly inhibited the proliferation and activationof T cells. Mechanisms involved are inhibition of CD25 and down-regulation of PA28 and IL-2 mRNAexpressions.

  19. SLy1 regulates T-cell proliferation during Listeria monocytogenes infection in a Foxo1-dependent manner.

    Science.gov (United States)

    Schäll, Daniel; Schmitt, Fee; Reis, Bernhard; Brandt, Simone; Beer-Hammer, Sandra

    2015-11-01

    Infection of mice with Listeria monocytogenes results in a strong T-cell response that is critical for an efficient defense. Here, we demonstrate that the adapter protein SLy1 (SH3-domain protein expressed in Lymphocytes 1) is essential for the generation of a fully functional T-cell response. The lack of SLy1 leads to reduced survival rates of infected mice. The increased susceptibility of SLy1 knock-out (KO) mice was caused by reduced proliferation of differentiated T cells. Ex vivo analyses of isolated SLy1 KO T cells displayed a dysregulation of Forkhead box protein O1 shuttling after TCR signaling, which resulted in an increased expression of cell cycle inhibiting genes, and therefore, reduced expansion of the T-cell population. Forkhead box protein O1 shuttles to the cytoplasm after phosphorylation in a protein complex including 14-3-3 proteins. Interestingly, we observed a similar regulation for the adapter protein SLy1, where TCR stimulation results in SLy1 phosphorylation and SLy1 export to the cytoplasm. Moreover, immunoprecipitation analyses revealed a binding of SLy1 to 14-3-3 proteins. Altogether, this study describes SLy1 as an immunoregulatory protein, which is involved in the generation of adaptive immune responses during L. monocytogenes infection, and provides a model of how SLy1 regulates T-cell proliferation. PMID:26306874

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

    International Nuclear Information System (INIS)

    To track epitope-specific CD4+ T cells at a single-cell level during influenza infection, the MHC class II-restricted OVA323-339 epitope was engineered into the neuraminidase stalk of influenza/A/WSN, creating a surrogate viral antigen. The recombinant virus, influenza A/WSN/OVAII, 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 OVA323-339 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

  1. 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

    OpenAIRE

    Cheng-Rong Yu; Dambuza, Ivy M.; Yong-Jun Lee; Frank, Gregory M.; Egwuagu, Charles E.

    2013-01-01

    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), p21wa...

  2. 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...

  3. Stimulated human peripheral T cells produce high amounts of IL-35 protein in a proliferation-dependent manner.

    Science.gov (United States)

    Guttek, Karina; Reinhold, Dirk

    2013-10-01

    The p35 subunit of IL-12 and the Epstein-Barr virus-induced gene 3 (EBI3) have been shown to form a heterodimeric cytokine, named interleukin-35 (IL-35). Recently, mRNA expression of both IL-12p35 and EBI3 was clearly shown in stimulated human T effector cells. Here, we investigated the production of IL-35 protein in human anti-CD3/CD28-stimulated pan T cells as well as T cell subpopulations using a specific human IL-35 ELISA system. We measured high concentrations of IL-35 (up to 3 ng/ml) in cell culture supernatants of stimulated pan T cells as well as CD4(+), CD8(+) and CD4(+)CD25(-) T cell subpopulations at 72 h after stimulation. Very low amounts of IL-35, in the range of 100pg/ml, were detectable in supernatants of resting T cells. These observations could be confirmed using a dot-blot assay for IL-12p35 and EBI3. High concentrations of IL-35 could be also measured in cell culture supernatants of both, resting and stimulated CD4(+)CD25(+) T cells. In order to learn more about the regulation of IL-35 production, we studied the effect of dexamethasone, cyclosporine A and rapamycin on IL-35 production of anti-CD3/CD28-stimulated human pan T cells as well as CD4(+) and CD8(+) T cell subpopulations. All three drugs significantly suppressed IL-35 production of these cells in a proliferation-dependent manner. In summary, we could show that stimulated human peripheral blood T cells of healthy donors produce high amounts of IL-35 protein. However, the biological function of this cytokine remains to be elucidated.

  4. Nematode-Derived Proteins Suppress Proliferation and Cytokine Production of Antigen-Specific T Cells via Induction of Cell Death

    Science.gov (United States)

    Hartmann, Wiebke; Brenz, Yannick; Kingsley, Manchang Tanyi; Ajonina-Ekoti, Irene; Brattig, Norbert W.; Liebau, Eva; Breloer, Minka

    2013-01-01

    In order to establish long-lasting infections in their mammalian host, filarial nematodes have developed sophisticated strategies to dampen their host’s immune response. Proteins that are actively secreted by the parasites have been shown to induce the expansion of regulatory T cells and to directly interfere with effector T cell function. Here, we analyze the suppressive capacity of Onchocercavolvulus-derived excreted/secreted proteins. Addition of two recombinant O. volvulus proteins, abundant larval transcript-2 (OvALT-2) and novel larval transcript-1 (OvNLT-1) to cell cultures of T cell receptor transgenic CD4+ and CD8+ T cells suppressed antigen-specific stimulation in vitro. Ovalbumin-specific CD4+ DO11.10 and OT-II T cells that had been stimulated with their cognate antigen in the presence of OvALT-2 or OvNLT-1 displayed reduced DNA synthesis quantified by 3H-thymidine incorporation and reduced cell division quantified by CFSE dilution. Furthermore, the IL-2 and IFN-γ response of ovalbumin-specific CD8+ OT-I T cells was suppressed by OvALT-2 and OvNLT-1. In contrast, another recombinant O. volvulus protein, microfilariae surface-associated antigen (Ov103), did not modulate T cell activation, thus serving as internal control for non-ESP-mediated artifacts. Suppressive capacity of the identified ESP was associated with induction of apoptosis in T cells demonstrated by increased exposure of phosphatidylserine on the plasma membrane. Of note, the digestion of recombinant proteins with proteinase K did not abolish the suppression of antigen-specific proliferation although the suppressive capacity of the identified excreted/secreted products was not mediated by low molecular weight contaminants in the undigested preparations. In summary, we identified two suppressive excreted/secreted products from O. volvulus, which interfere with the function of antigen-specific T cells in vitro. PMID:23861729

  5. Nematode-derived proteins suppress proliferation and cytokine production of antigen-specific T cells via induction of cell death.

    Directory of Open Access Journals (Sweden)

    Wiebke Hartmann

    Full Text Available In order to establish long-lasting infections in their mammalian host, filarial nematodes have developed sophisticated strategies to dampen their host's immune response. Proteins that are actively secreted by the parasites have been shown to induce the expansion of regulatory T cells and to directly interfere with effector T cell function. Here, we analyze the suppressive capacity of Onchocercavolvulus-derived excreted/secreted proteins. Addition of two recombinant O. volvulus proteins, abundant larval transcript-2 (OvALT-2 and novel larval transcript-1 (OvNLT-1 to cell cultures of T cell receptor transgenic CD4(+ and CD8(+ T cells suppressed antigen-specific stimulation in vitro. Ovalbumin-specific CD4(+ DO11.10 and OT-II T cells that had been stimulated with their cognate antigen in the presence of OvALT-2 or OvNLT-1 displayed reduced DNA synthesis quantified by (3H-thymidine incorporation and reduced cell division quantified by CFSE dilution. Furthermore, the IL-2 and IFN-γ response of ovalbumin-specific CD8(+ OT-I T cells was suppressed by OvALT-2 and OvNLT-1. In contrast, another recombinant O. volvulus protein, microfilariae surface-associated antigen (Ov103, did not modulate T cell activation, thus serving as internal control for non-ESP-mediated artifacts. Suppressive capacity of the identified ESP was associated with induction of apoptosis in T cells demonstrated by increased exposure of phosphatidylserine on the plasma membrane. Of note, the digestion of recombinant proteins with proteinase K did not abolish the suppression of antigen-specific proliferation although the suppressive capacity of the identified excreted/secreted products was not mediated by low molecular weight contaminants in the undigested preparations. In summary, we identified two suppressive excreted/secreted products from O. volvulus, which interfere with the function of antigen-specific T cells in vitro.

  6. IL17 producing γδT cells induce angiogenesis and are associated with poor survival in gallbladder cancer patients.

    Science.gov (United States)

    Sudam Patil, Rushikesh; Umesh Shah, Sagar; Vinayak Shrikhande, Shailesh; Goel, Mahesh; Prabhakar Dikshit, Rajesh; Vivek Chiplunkar, Shubhada

    2016-08-15

    Despite conventional treatment modalities, gallbladder cancer (GBC) remains a highly lethal malignancy. Prognostic biomarkers and effective adjuvant immunotherapy for GBC are not available. In the recent past, immunotherapeutic approaches targeting tumor associated inflammation have gained importance but the mediators of inflammatory circuit remain unexplored in GBC patients. In the current prospective study, we investigated the role of IL17 producing TCRγδ(+) (Tγδ17), CD4(+) (Th17), CD8(+) (Tc17) and regulatory T cells (Tregs) in pathogenesis of GBC. Analysis by multi-color flow cytometry revealed that compared to healthy individuals (HI), Tγδ17, Th17 and Tc17 cells were increased in peripheral blood mononuclear cells (PBMCs) and tumor infiltrating lymphocytes (TIL) of GBC patients. Tregs were decreased in PBMCs but increased in TILs of GBC patients. The suppressive potential of Tregs from GBC patients and HI were comparable. Serum cytokines profile of GBC patients showed elevated levels of cytokines (IL6, IL23 and IL1β) required for polarization and/or stabilization of IL17 producing cells. We demonstrated that Tγδ17 cells migrate toward tumor bed using CXCL9-CXCR3 axis. IL17 secreted by Tγδ17 induced productions of vascular endothelial growth factor and other angiogenesis related factors in GBC cells. Tγδ17 cells promote vasculogenesis as studied by chick chorioallantoic membrane assay. Survival analysis showed that Tγδ17, Th17 and Treg cells in peripheral blood were associated with poor survival of GBC patients. Our findings suggest that Tγδ17 is a protumorigenic subtype of γδT cells which induces angiogenesis. Tγδ17 may be considered as a predictive biomarker in GBC thus opening avenues for targeted therapies. PMID:27062572

  7. Limited transplantation of antigen-expressing hematopoietic stem cells induces long-lasting cytotoxic T cell responses.

    Directory of Open Access Journals (Sweden)

    Warren L Denning

    Full Text Available Harnessing the ability of cytotoxic T lymphocytes (CTLs to recognize and eradicate tumor or pathogen-infected cells is a critical goal of modern immune-based therapies. Although multiple immunization strategies efficiently induce high levels of antigen-specific CTLs, the initial increase is typically followed by a rapid contraction phase resulting in a sharp decline in the frequency of functional CTLs. We describe a novel approach to immunotherapy based on a transplantation of low numbers of antigen-expressing hematopoietic stem cells (HSCs following nonmyeloablative or partially myeloablative conditioning. Continuous antigen presentation by a limited number of differentiated transgenic hematopoietic cells results in an induction and prolonged maintenance of fully functional effector T cell responses in a mouse model. Recipient animals display high levels of antigen-specific CTLs four months following transplantation in contrast to dendritic cell-immunized animals in which the response typically declines at 4-6 weeks post-immunization. Majority of HSC-induced antigen-specific CD8+ T cells display central memory phenotype, efficiently kill target cells in vivo, and protect recipients against tumor growth in a preventive setting. Furthermore, we confirm previously published observation that high level engraftment of antigen-expressing HSCs following myeloablative conditioning results in tolerance and an absence of specific cytotoxic activity in vivo. In conclusion, the data presented here supports potential application of immunization by limited transplantation of antigen-expressing HSCs for the prevention and treatment of cancer and therapeutic immunization of chronic infectious diseases such as HIV-1/AIDS.

  8. 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.

  9. 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...

  10. Differential effects of polysulfated polysaccharide on experimental encephalomyelitis, proliferation of autoimmune T cells, and inhibition of heparanase activity.

    Science.gov (United States)

    Hershkoviz, R; Mor, F; Miao, H Q; Vlodavsky, I; Lider, O

    1995-10-01

    The extravasation of activated T lymphocytes through blood vessel walls and their migration to inflammatory loci are associated with secretion of extracellular matrix (ECM)-degrading enzymes, such as heparanase, which degrades heparan sulfate (HS) moieties of the ECM. The HS-degrading activity of heparanase was found to be inhibited by HS and heparin. Since induction of experimental autoimmune encephalomyelitis (EAE) requires extravasation and migration of autoimmune T cells, degradation of ECM by heparanase is expected to be involved in induction of the disease. Herein, we examined whether laminarin sulfate, a polysulfated polysaccharide (PSS) isolated from the cell walls of seaweeds and subjected to chemical sulfation, could inhibit ECM degradation by mammalian heparanase, and could prevent EAE. PSS was a more potent inhibitor of heparanase-mediated degradation of ECM than heparin. In-vivo, PSS, injected once a week, inhibited the severity of actively-induced EAE in rats. However, inhibition of EAE was not due to an overall suppression of autoimmune T cells, since PSS enhanced the proliferation of myelin basic protein (MBP)-specific, encephalitogenic T cells. PSS-activated autoimmune T cells, but not MBP-activated cells, failed to induce EAE in recipient rats. Moreover, rats injected with PSS-activated T cells were resistant to induction of EAE by anti-MBP CD4+ T cells. Thus, PSS may have potential clinical applications in the treatment of autoimmune diseases. PMID:8579728

  11. Role of the multichain IL-2 receptor complex in the control of normal and malignant T-cell proliferation

    Energy Technology Data Exchange (ETDEWEB)

    Waldmann, T.A.

    1987-11-01

    Antigen-induced activation of resting T-cells induces the synthesis of interleukin-2 (IL-2), as well as the expression of specific cell surface receptors for this lymphokine. There are at least two forms of the cellular receptors for IL-2, one with a very high affinity and the other with a lower affinity. The authors have identified two IL-2 binding peptides, a 55-kd peptide reactive with the anti-Tac monoclonal antibody, and a novel 75-kd non-Tac IL-2 binding peptide. Cell lines bearing either the p55, Tac, or the p75 peptide along manifested low-affinity IL-2 binding, whereas cell lines bearing both peptides manifested both high- and low-affinity receptors. Fusion of cell membranes from low-affinity IL-2 binding cells bearing the Tac peptide alone with membranes from a cell line bearing the p75 peptide alone generates hybrid membranes bearing high-affinity receptors. They propose a multichain model for the high-affinity IL-2 receptor in which both the Tac and the p75 IL-2 binding peptides are associated in a receptor complex. In contrast to resting T-cells, human T-cell lymphotropic virus I-associated adult T-cell leukemia cells constitutively express large numbers of IL-2 receptors. Because IL-2 receptors are present on the malignant T-cells but not on normal resting cells, clinical trials have been initiated in which patients with adult T-cell leukemia are being treated with either unmodified or toxin-conjugated forms of anti-Tac monoclonal antibody directed toward this growth factor receptor. Cross-linking studies were done using (/sup 125/I) IL-2.

  12. Naive CD4 T Cell Proliferation Is Controlled by Mammalian Target of Rapamycin Regulation of GRAIL Expression1

    OpenAIRE

    Lin, Jack T; Lineberry, Neil B.; Kattah, Michael G; Su, Leon L.; Utz, Paul J; Fathman, C. Garrison; Wu, Linda

    2009-01-01

    In this study, we demonstrate that the E3 ubiquitin ligase gene related to anergy in lymphocytes (GRAIL) is expressed in quiescent naive mouse and human CD4 T cells and has a functional role in inhibiting naive T cell proliferation. Following TCR engagement, CD28 costimulation results in the expression of IL-2 whose signaling through its receptor activates the Akt-mammalian target of rapamycin (mTOR) pathway. Activation of mTOR allows selective mRNA translation, including the epistatic regula...

  13. Regulatory T Cell Induced by Poria cocos Bark Exert Therapeutic Effects in Murine Models of Atopic Dermatitis and Food Allergy

    Directory of Open Access Journals (Sweden)

    Min-Jung Bae

    2016-01-01

    Full Text Available The prevalence of allergic disorders including atopic dermatitis (AD and food allergy (FA has increased dramatically in pediatric populations, but there is no effective drug available for their management. Therefore, trials are required for the development of safe therapeutic agents such as herbal medicines. We determined whether orally administered Poria cocos bark (PCB extract could exert immunosuppressive effects on allergic and inflammatory symptoms of AD and FA. For both AD, which was induced using house dust mite extract, and FA, which was induced by exposure to ovalbumin, model mice were orally treated with PCB extract for 62 days and 18 days, respectively. We also investigated the inductive effect of PCB extract on the generation and maintenance of Foxp3+CD4+ regulatory T cells (Tregs. The symptoms of AD and FA were ameliorated by the administration of PCB extract. Furthermore, PCB extract inhibited the Th2-related cytokines and increased the population of Foxp3+CD4+ Tregs in both AD and FA models. In ex vivo experiments, PCB extract promoted the functional differentiation of Foxp3+CD4+ Tregs, which is dependent on aryl hydrocarbon receptor activation. Thus, PCB extract has potential as an oral immune suppressor for the treatment of AD and FA through the generation of Tregs.

  14. Regulatory T Cell Induced by Poria cocos Bark Exert Therapeutic Effects in Murine Models of Atopic Dermatitis and Food Allergy.

    Science.gov (United States)

    Bae, Min-Jung; See, Hye-Jeong; Choi, Gyeyoung; Kang, Chang-Yuil; Shon, Dong-Hwa; Shin, Hee Soon

    2016-01-01

    The prevalence of allergic disorders including atopic dermatitis (AD) and food allergy (FA) has increased dramatically in pediatric populations, but there is no effective drug available for their management. Therefore, trials are required for the development of safe therapeutic agents such as herbal medicines. We determined whether orally administered Poria cocos bark (PCB) extract could exert immunosuppressive effects on allergic and inflammatory symptoms of AD and FA. For both AD, which was induced using house dust mite extract, and FA, which was induced by exposure to ovalbumin, model mice were orally treated with PCB extract for 62 days and 18 days, respectively. We also investigated the inductive effect of PCB extract on the generation and maintenance of Foxp3(+)CD4(+) regulatory T cells (Tregs). The symptoms of AD and FA were ameliorated by the administration of PCB extract. Furthermore, PCB extract inhibited the Th2-related cytokines and increased the population of Foxp3(+)CD4(+) Tregs in both AD and FA models. In ex vivo experiments, PCB extract promoted the functional differentiation of Foxp3(+)CD4(+) Tregs, which is dependent on aryl hydrocarbon receptor activation. Thus, PCB extract has potential as an oral immune suppressor for the treatment of AD and FA through the generation of Tregs. PMID:27445434

  15. Human Adipose-Derived Stromal/Stem Cells Induce Functional CD4+CD25+FoxP3+CD127− Regulatory T Cells Under Low Oxygen Culture Conditions

    OpenAIRE

    Frazier, Trivia P.; McLachlan, James B.; Gimble, Jeffrey M.; Tucker, Hugh A; Brian G Rowan

    2014-01-01

    Human adipose tissue stromal/stem cells (ASCs) are known to induce proliferation of resting T cells under ambient (21%) O2 conditions; however, ASCs exist physiologically under lower oxygen (5% O2) conditions in adipose tissue. The effects of low oxygen levels on ASC immunomodulation of T cells are unknown. In this study, we show that ASCs stimulated proliferation of naive CD4+ T cells and the percentage of CD25+ T cells was significantly increased under both low and ambient O2. Forkhead box ...

  16. CD28 ligation increases macrophage suppression of T-cell proliferation.

    Science.gov (United States)

    Silberman, Daniel; Bucknum, Amanda; Bartlett, Thomas; Composto, Gabriella; Kozlowski, Megan; Walker, Amanda; Werda, Amy; Cua, Jackelyn; Sharpe, Arlene H; Somerville, John E; Riggs, James E

    2012-07-01

    When compared to spleen or lymph node cells, resident peritoneal cavity cells respond poorly to T-cell activation in vitro. The greater proportional representation of macrophages in this cell source has been shown to actively suppress the T-cell response. Peritoneal macrophages exhibit an immature phenotype (MHC class II(lo), B7(lo)) that reduces their efficacy as antigen-presenting cells. Furthermore, these cells readily express inducible nitric oxide synthase (iNOS), an enzyme that promotes T-cell tolerance by catabolism of the limiting amino acid arginine. Here, we investigate the ability of exogenous T-cell costimulation to recover the peritoneal T-cell response. We show that CD28 ligation failed to recover the peritoneal T-cell response and actually suppressed responses that had been recovered by inhibiting iNOS. As indicated by cytokine ELISpot and neutralizing monoclonal antibody (mAb) treatment, this 'cosuppression' response was due to CD28 ligation increasing the number of interferon (IFN)-γ-secreting cells. Our results illustrate that cellular composition and cytokine milieu influence T-cell costimulation biology.Cellular & Molecular Immunology advance online publication, 23 April 2012; doi:10.1038/cmi.2012.13.

  17. 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.

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

    Energy Technology Data Exchange (ETDEWEB)

    Morganroth, G.S.; Chan, L.S.; Weinstein, G.D.; Voorhees, J.J.; Cooper, K.D. (Univ. of Michigan Medical School, Ann Arbor (USA))

    1991-03-01

    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.

  19. HIV-1 Vpr accelerates viral replication during acute infection by exploitation of proliferating CD4+ T cells in vivo.

    Directory of Open Access Journals (Sweden)

    Kei Sato

    Full Text Available The precise role of viral protein R (Vpr, an HIV-1-encoded protein, during HIV-1 infection and its contribution to the development of AIDS remain unclear. Previous reports have shown that Vpr has the ability to cause G2 cell cycle arrest and apoptosis in HIV-1-infected cells in vitro. In addition, vpr is highly conserved in transmitted/founder HIV-1s and in all primate lentiviruses, which are evolutionarily related to HIV-1. Although these findings suggest an important role of Vpr in HIV-1 pathogenesis, its direct evidence in vivo has not been shown. Here, by using a human hematopoietic stem cell-transplanted humanized mouse model, we demonstrated that Vpr causes G2 cell cycle arrest and apoptosis predominantly in proliferating CCR5(+ CD4(+ T cells, which mainly consist of regulatory CD4(+ T cells (Tregs, resulting in Treg depletion and enhanced virus production during acute infection. The Vpr-dependent enhancement of virus replication and Treg depletion is observed in CCR5-tropic but not CXCR4-tropic HIV-1-infected mice, suggesting that these effects are dependent on the coreceptor usage by HIV-1. Immune activation was observed in CCR5-tropic wild-type but not in vpr-deficient HIV-1-infected humanized mice. When humanized mice were treated with denileukin diftitox (DD, to deplete Tregs, DD-treated humanized mice showed massive activation/proliferation of memory T cells compared to the untreated group. This activation/proliferation enhanced CCR5 expression in memory CD4(+ T cells and rendered them more susceptible to CCR5-tropic wild-type HIV-1 infection than to vpr-deficient virus. Taken together, these results suggest that Vpr takes advantage of proliferating CCR5(+ CD4(+ T cells for enhancing viremia of CCR5-tropic HIV-1. Because Tregs exist in a higher cycling state than other T cell subsets, Tregs appear to be more vulnerable to exploitation by Vpr during acute HIV-1 infection.

  20. Characterization and functional studies of forkhead box protein 3(-) lymphocyte activation gene 3(+) CD4(+) regulatory T cells induced by mucosal B cells.

    Science.gov (United States)

    Chu, K-H; Chiang, B-L

    2015-05-01

    The induction of mucosal tolerance has been demonstrated to be an effective therapeutic approach for the treatment of allergic diseases. Our previous study demonstrated that Peyer's patch B cells could convert naive T cells into regulatory T cells (so-called Treg -of-B(P) cells); however, it is important to characterize this particular subset of Treg -of-B cells for future applications. This study aimed to investigate the role of lymphocyte activating gene 3 (LAG3) in mediating the regulatory function of Treg -of-B(P) cells induced by mucosal follicular B (FOB) cells. Microarray analysis and real-time polymerase chain reaction (PCR) were used to assess the gene expression pattern of Treg -of-B(P) cells. To evaluate the role of LAG3, the in-vitro suppressive function and the alleviation of airway inflammation in a murine model of asthma was assessed. Our data indicated that FOB cells isolated from Peyer's patches had the ability to generate more suppressive Treg -of-B cells with LAG3 expression, compared with CD23(lo) CD21(lo) B cells. LAG3 is not only a marker for Treg -of-B(P) cells, but also participate in the suppressive ability. Moreover, CCR4 and CCR6 could be detected on the LAG3(+) , not LAG3(-) , Treg -of-B(P) cells and would help cells homing to allergic lung. In the murine model of asthma, the adoptive transfer of LAG3(+) Treg -of-B(P) cells was able to sufficiently suppress T helper type 2 (Th2) cytokine production, eosinophil infiltration and alleviate asthmatic symptoms. LAG3 was expressed in Treg -of-B(P) cells and was also involved in the function of Treg -of-B(P) cells. In the future, this particular subset of Treg -of-B cells might be used to alleviate allergic symptoms. PMID:25581421

  1. Lck is involved in interleukin-2 induced proliferation but not cell survival in human T cells through a MAP kinase-independent pathway

    DEFF Research Database (Denmark)

    Brockdorff, J; Nielsen, M; Kaltoft, K;

    2000-01-01

    found that an IL-2-sensitive, human mycosis fungoides-derived tumor T cell line is Lck negative, and that the IL-2-induced MAP kinase activation is comparable to non-cancerous T cells, although a little delayed in kinetics. An Lck expressing clone was established by transfecting Lck into mycosis...... fungoides tumor T cells, but Lck had no influence on the delayed kinetics of MAP kinase activation, indicating that Lck is not essential for MAP kinase activation in mycosis fungoides tumor T cells or in non-cancerous T cells. Taken together, this indicates that Lck is involved in IL-2-induced proliferation...

  2. Memory-like CD8⁺ T cells generated during homeostatic proliferation defer to antigen-experienced memory cells

    OpenAIRE

    Cheung, Kitty Pui Hang

    2009-01-01

    Naïve T cells proliferate in response to lymphopenia and acquire the phenotypic and functional qualities of memory T cells, providing enhanced protection against infection. How well 'memory-like' T cells generated during lymphopenia-induced homeostatic proliferation (HP-memory) differentiate into secondary memory cells and compete with antigen-experienced 'true-memory' cells is previously unknown. We found that CD8⁺ HP-memory T cells generated robust responses upon infection and produced a se...

  3. 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.

  4. [Lipopolysaccharide promotes the proliferation of CD4(+) T cells by modulating the survive and cytokine secretion of dendritic cells].

    Science.gov (United States)

    Chen, Song; Lu, Lisha; Wang, Weiqiang; Xue, Ting; Yu, Juan; Sun, Zhina; Zhao, Chunxiao; Liao, Fang

    2016-09-01

    Objective To explore the mechanism modulating the function of dendritic cells (DCs) and promoting the T cell response by lipopolysaccharide (LPS). Methods Splenic DCs were purified with anti-CD11c immunomagnetic beads. After DCs were stimulated with LPS, the expressions of co-stimulatory molecules CD80 and CD86 on the DCs were detected by flow cytometry. The protein levels of pro-inflammatory cytokines interleukin 4 (IL-4), IL-5, IL-6, IL-12p40, IL-12p70 and tumor necrosis factor alpha (TNF-α) in the culture supernatant were measured by ELISA. The apoptotic levels of DCs which were labeled with annexinV-FITC/PI were determined by flow cytometry. The phosphorylation level of nuclear factor κB P65 (NF-κB P65) was assessed by phos-flow. The mRNA levels of variable genes in microarray were determined by real-time PCR. The proliferation of CD4(+) T cells which were co-cultured with OVA323-329-treated DCs was analyzed by flow cytometry. Results The purity of DCs reached over 93% after isolation. LPS up-regulated the expressions of CD80 and CD86 and enhanced DCs-mediated proliferation of CD4(+) T cells. In addition, LPS increased the protein levels of IL-12p40, TNF-α and IL-6, and inhibited the apoptosis of DCs through the NF-κB signaling pathway. Conclusion LPS could enhance DC-mediated proliferation of CD4(+) T cells by modulating the DCs survival and cytokine secretion. PMID:27609566

  5. Tumor-associated macrophages promote tumor cell proliferation in nasopharyngeal NK/T-cell lymphoma

    OpenAIRE

    Liu, Yixiong; Fan, Linni; Wang, Yingmei; Li, Peifeng; Zhu, Jin; Wang, Lu; Zhang, Weichen; Zhang, Yuehua; Huang, Gaosheng

    2014-01-01

    Objective: To explore the relationship between the number of tumor-associated macrophages (TAMs) and proliferative activity of tumor cells and the relationship between two macrophage biomarkers CD68 and CD163 in nasopharyngeal NK/T-cell lymphoma. Methods: Immunohistochemistry was used to reconfirm the diagnosis of nasal NK/T-cell lymphoma and detect the numbers of TAMs and the ki-67 label index of the tumor cells in all 31 cases. In addition, 12 cases of inflammatory cases were collected as c...

  6. Comparison of microglia and infiltrating CD11c+ cells as antigen presenting cells for T cell proliferation and cytokine response

    DEFF Research Database (Denmark)

    Wlodarczyk, Agnieszka; Løbner, Morten; Cédile, Oriane;

    2014-01-01

    BACKGROUND: Tissue-resident antigen-presenting cells (APC) exert a major influence on the local immune environment. Microglia are resident myeloid cells in the central nervous system (CNS), deriving from early post-embryonic precursors, distinct from adult hematopoietic lineages. Dendritic cells...... (DC) and macrophages infiltrate the CNS during experimental autoimmune encephalomyelitis (EAE). Microglia are not considered to be as effective APC as DC or macrophages. METHODS: In this work we compared the antigen presenting capacity of CD11c+ and CD11c- microglia subsets with infiltrating CD11c...... for cytokine expression. They were co-cultured with primed T cells to measure induction of T cell proliferation and cytokine response. RESULTS: The number of CD11c+ microglia cells increased dramatically in EAE. They expressed equivalent levels of major histocompatibility complex and co-stimulatory ligands CD...

  7. Pharmacological inhibition of carbonic anhydrase XII interferes with cell proliferation and induces cell apoptosis in T-cell lymphomas.

    Science.gov (United States)

    Lounnas, Nadia; Rosilio, Célia; Nebout, Marielle; Mary, Didier; Griessinger, Emmanuel; Neffati, Zouhour; Chiche, Johanna; Spits, Hergen; Hagenbeek, Thijs J; Asnafi, Vahid; Poulsen, Sally-Ann; Supuran, Claudiu T; Peyron, Jean-François; Imbert, Véronique

    2013-06-01

    The membrane-bound carbonic anhydrase isoforms CAIX and CAXII, underpin a pH-regulating system that enables hypoxic tumor cell survival. Here, we observed for the first time an upregulation of CAXII in T-cell acute lymphoblastic leukemia/lymphoma (T-ALL/LL) cells. First we showed that CAXII is overexpressed in thymocytes from tPTEN-/- mice suffering of T lymphoma and that its pharmacological inhibition decreased cell proliferation and induced apoptosis. The same results were observed with the SupT1 human T cell lymphoma line. In addition we observed an upregulation of CAXII in human T-ALL samples supporting the case that CAXII may represent a new therapeutic target for T-ALL/LL. PMID:23348702

  8. Inhibition of proliferation by agricultural plant extracts in seven human adult T-cell leukaemia (ATL)-related cell lines.

    Science.gov (United States)

    Kai, Hisahiro; Akamatsu, Ena; Torii, Eri; Kodama, Hiroko; Yukizaki, Chizuko; Sakakibara, Yoichi; Suiko, Masahito; Morishita, Kazuhiro; Kataoka, Hiroaki; Matsuno, Koji

    2011-07-01

    Adult T-cell leukaemia (ATL) is caused by human T-cell leukaemia virus type I (HTLV-I) infection and is resistant to conventional chemotherapy. We evaluated the inhibitory effects of agricultural plants on the proliferation of seven ATL-related human leukaemia cells, using three ATL cell lines (ED, Su9T01 and S1T), two human T-cell lines transformed by HTLV-I infection (HUT-102 and MT-2) and two HTLV-I-negative human T-cell acute lymphoblastic leukaemia cell lines (Jurkat and MOLT-4). A total of 52 samples of 80% ethanol extracts obtained from 30 types of agricultural plants were examined. On the basis of IC(50) values, we selected samples with greater activity than genistein, which was used as a positive control. The highest inhibitory effect was observed with extracts from leaves of Vaccinium virgatum Aiton (blueberry) on four cell lines (ED, Su9T01, HUT-102 and Jurkat); seeds of Momordica charantia L. (bitter gourd) exhibited the second highest activity. The bitter gourd seeds suppressed the proliferation of three cell lines (Su9T01, HUT-102 and Jurkat). The extracts from edible parts of Ipomea batatas LAM. (sweet potato), edible parts of Colocasia esculenta (L.) Schott (taro), skin of taro and seeds of Prunus mume Sieb. et Zucc. (mume) showed markedly greater inhibitory effects on Su9T01 than genistein. These findings suggest that ATL-preventative bioactive compounds may exist in these agricultural plants, which are considered to be functional foods. PMID:21293936

  9. Therapeutic T cells induce tumor-directed chemotaxis of innate immune cells through tumor-specific secretion of chemokines and stimulation of B16BL6 melanoma to secrete chemokines

    Directory of Open Access Journals (Sweden)

    Fox Bernard A

    2007-11-01

    Full Text Available Abstract Background The mechanisms by which tumor-specific T cells induce regression of established metastases are not fully characterized. In using the poorly immunogenic B16BL6-D5 (D5 melanoma model we reported that T cell-mediated tumor regression can occur independently of perforin, IFN-γ or the combination of both. Characterization of regressing pulmonary metastases identified macrophages as a major component of the cells infiltrating the tumor after adoptive transfer of effector T cells. This led us to hypothesize that macrophages played a central role in tumor regression following T-cell transfer. Here, we sought to determine the factors responsible for the infiltration of macrophages at the tumor site. Methods These studies used the poorly immunogenic D5 melanoma model. Tumor-specific effector T cells, generated from tumor vaccine-draining lymph nodes (TVDLN, were used for adoptive immunotherapy and in vitro analysis of chemokine expression. Cellular infiltrates into pulmonary metastases were determined by immunohistochemistry. Chemokine expression by the D5 melanoma following co-culture with T cells, IFN-γ or TNF-α was determined by RT-PCR and ELISA. Functional activity of chemokines was confirmed using a macrophage migration assay. T cell activation of macrophages to release nitric oxide (NO was determined using GRIES reagent. Results We observed that tumor-specific T cells with a type 1 cytokine profile also expressed message for and secreted RANTES, MIP-1α and MIP-1β following stimulation with specific tumor. Unexpectedly, D5 melanoma cells cultured with IFN-γ or TNF-α, two type 1 cytokines expressed by therapeutic T cells, secreted Keratinocyte Chemoattractant (KC, MCP-1, IP-10 and RANTES and expressed mRNA for MIG. The chemokines released by T cells and cytokine-stimulated tumor cells were functional and induced migration of the DJ2PM macrophage cell line. Additionally, tumor-specific stimulation of wt or perforin

  10. Differential activation of proliferation and cytotoxicity in human T-cell lymphotropic virus type I Tax-specific CD8 T cells by an altered peptide ligand.

    OpenAIRE

    Höllsberg, P; Weber, W E; Dangond, F; Batra, V; Sette, A.; Hafler, D A

    1995-01-01

    Human T-cell leukemia virus type I (HTLV-I) gives rise to a neurologic disease known as HTLV-I-associated myelopathy/tropical spastic paraparesis (HAM/TSP). Although the pathogenesis of the disease is unknown, the presence of a remarkably high frequency of Tax-specific, cytotoxic CD8 T cells may suggest a role of these cells in the development of HAM/TSP. Antigen-mediated signaling in a CD8 T-cell clone specific for the Tax(11-19) peptide of HTLV-I was studied using analog peptides substitute...

  11. Malignant T cells exhibit CD45 resistant Stat3 activation and proliferation in cutaneous

    DEFF Research Database (Denmark)

    Krejsgaard, Thorbjørn Frej; Helvad, Rikke; Ralfkiaer, 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......-mediated inhibition of proliferation. In conclusion, our data suggest that CD45 dysregulation might play a role in the aberrant proliferation and Jak3/Stat3 activation in CTCL....

  12. Modulation of T cell proliferation and cytokine response by Plumbagin, extracted from Plumbago zeylanica in collagen induced arthritis

    Directory of Open Access Journals (Sweden)

    Poosarla Aparanji

    2011-11-01

    Full Text Available Abstract Background The extracts of Plumbago zeylanica have been used in China and other Asian countries as folk medicine for the treatment of cancer, rheumatoid arthritis and dysmenorrhoea. Effect of Plumbagin (5-hydroxy-2-methyl-1,4-naphthoquinone purified from Plumbago zeylanica on Con A induced T cell proliferation was studied in spleen cells from collagen induced arthritic DBA/1 mice. Methods The DBA/1 mice (five per each group were immunized with 0.1 mL of collagen (emulsified in CFA by intradermal injection at the base of the tail. On day 20, mice were given a booster dose of collagen (emulsified in IFA through the same route. Plumbagin was given at different concentrations (3.3, 6.6, 13.3 mg/kg body weight intraperitoneally. Control mice received olive oil alone. The Con A induced T cell proliferative responses of arthritic and Plumbagin treated mice were studied by cell culture experiments using tritiated Thymidine. In addition the cytokine levels were estimated from the in vitro spleen culture supernatants of arthritic mice primed with different concentrations of Plumbagin by ELISA. Results Plumbagin enhanced the decreased Con A induced T cell proliferation and Interleukin-2 production in arthritic mice. Moreover elevated levels of IFN- γ were found to be decreased in Plumbagin treated spleen cell culture supernatants. Subclasses of IgG were found to be decreased by Plumbagin treatment, IgG2a reduction seems to be more prominent. Conclusion The results obtained in the current study indicate that Plumbagin is very effective in the mechanism based treatment of Rheumatoid arthritis.

  13. 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.

  14. The role of peroxisome proliferator-activated receptor-β/δ in epidermal growth factor-induced HaCaT cell proliferation

    International Nuclear Information System (INIS)

    Epidermal growth factor (EGF) has been shown to be a potent mitogen for epidermal cells both in vitro and in vivo, thus contributing to the development of an organism. It has recently become clear that peroxisome proliferator-activated receptor-β/δ (PPARβ/δ) expression and activation is involved in the cell proliferation. However, little is known about the role of PPARβ/δ in EGF-induced proliferation of HaCaT keratinocytes. In this study, HaCaT cells were cultured in the presence and absence of EGF and we identified that EGF induced an increase of PPARβ/δ mRNA and protein level expression in time-dependent and dose-dependent manner, and AG1487, an EGF receptor (EGFR) special inhibitor, caused attenuation of PPARβ/δ protein expression. Electrophoretic mobility shift assay (EMSA) revealed that EGF significantly increased PPARβ/δ binding activity in HaCaT keratinocytes. Antisense phosphorothioate oligonucleotides (asODNs) against PPARβ/δ caused selectively inhibition of PPARβ/δ protein content induced by EGF and significantly attenuated EGF-mediated cell proliferation. Treatment of the cells with L165041, a specific synthetic ligand for PPARβ/δ, significantly enhanced EGF-mediated cell proliferation. Finally, c-Jun ablation inhibited PPARβ/δ up-regulation induced by EGF, and chromatin immunoprecipitation (ChIP) showed that c-Jun bound to the PPARβ/δ promoter and the binding increased in EGF-stimulated cells. These results demonstrate that EGF induces PPARβ/δ expression in a c-Jun-dependent manner and PPARβ/δ plays a vital role in EGF-stimulated proliferation of HaCaT cells

  15. Lymphatic endothelial cells induce tolerance via PD-L1 and lack of costimulation leading to high-level PD-1 expression on CD8 T cells

    Science.gov (United States)

    Tewalt, Eric F.; Cohen, Jarish N.; Rouhani, Sherin J.; Guidi, Cynthia J.; Qiao, Hui; Fahl, Shawn P.; Conaway, Mark R.; Bender, Timothy P.; Tung, Kenneth S.; Vella, Anthony T.; Adler, Adam J.; Chen, Lieping

    2012-01-01

    Lymphatic endothelial cells (LECs) induce peripheral tolerance by direct presentation to CD8 T cells (TCD8). We demonstrate that LECs mediate deletion only via programmed cell death-1 (PD-1) ligand 1, despite expressing ligands for the CD160, B- and T-lymphocyte attenuator, and lymphocyte activation gene-3 inhibitory pathways. LECs induce activation and proliferation of TCD8, but lack of costimulation through 4-1BB leads to rapid high-level expression of PD-1, which in turn inhibits up-regulation of the high-affinity IL-2 receptor that is necessary for TCD8 survival. Rescue of tyrosinase-specific TCD8 by interference with PD-1 or provision of costimulation results in autoimmune vitiligo, demonstrating that LECs are significant, albeit suboptimal, antigen-presenting cells. Because LECs express numerous peripheral tissue antigens, lack of costimulation coupled to rapid high-level up-regulation of inhibitory receptors may be generally important in systemic peripheral tolerance. PMID:22993390

  16. 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)

    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.

  17. Sialic acid-modified antigens impose tolerance via inhibition of T-cell proliferation and de novo induction of regulatory T cells.

    Science.gov (United States)

    Perdicchio, Maurizio; Ilarregui, Juan M; Verstege, Marleen I; Cornelissen, Lenneke A M; Schetters, Sjoerd T T; Engels, Steef; Ambrosini, Martino; Kalay, Hakan; Veninga, Henrike; den Haan, Joke M M; van Berkel, Lisette A; Samsom, Janneke N; Crocker, Paul R; Sparwasser, Tim; Berod, Luciana; Garcia-Vallejo, Juan J; van Kooyk, Yvette; Unger, Wendy W J

    2016-03-22

    Sialic acids are negatively charged nine-carbon carboxylated monosaccharides that often cap glycans on glycosylated proteins and lipids. Because of their strategic location at the cell surface, sialic acids contribute to interactions that are critical for immune homeostasis via interactions with sialic acid-binding Ig-type lectins (siglecs). In particular, these interactions may be of importance in cases where sialic acids may be overexpressed, such as on certain pathogens and tumors. We now demonstrate that modification of antigens with sialic acids (Sia-antigens) regulates the generation of antigen-specific regulatory T (Treg) cells via dendritic cells (DCs). Additionally, DCs that take up Sia-antigen prevent formation of effector CD4(+) and CD8(+)T cells. Importantly, the regulatory properties endowed on DCs upon Sia-antigen uptake are antigen-specific: only T cells responsive to the sialylated antigen become tolerized. In vivo, injection of Sia-antigen-loaded DCs increased de novo Treg-cell numbers and dampened effector T-cell expansion and IFN-γ production. The dual tolerogenic features that Sia-antigen imposed on DCs are Siglec-E-mediated and maintained under inflammatory conditions. Moreover, loading DCs with Sia-antigens not only inhibited the function of in vitro-established Th1 and Th17 effector T cells but also significantly dampened ex vivo myelin-reactive T cells, present in the circulation of mice with experimental autoimmune encephalomyelitis. These data indicate that sialic acid-modified antigens instruct DCs in an antigen-specific tolerogenic programming, enhancing Treg cells and reducing the generation and propagation of inflammatory T cells. Our data suggest that sialylation of antigens provides an attractive way to induce antigen-specific immune tolerance. PMID:26941238

  18. Proliferation Response to Interleukin-2 and Jak/Stat Activation of T Cells Immortalized by Human T-Cell Lymphotropic Virus Type 1 Is Independent of Open Reading Frame I Expression

    OpenAIRE

    Collins, Nathaniel D.; D’Souza, Celine; Albrecht, Björn; Robek, Michael D.; Ratner, Lee; Ding, Wei; Green, Patrick L.; Lairmore, Michael D.

    1999-01-01

    Human T-cell lymphotropic virus type 1 (HTLV-1), a complex retrovirus, encodes a hydrophobic 12-kD protein from pX open reading frame (ORF) I that localizes to cellular endomembranes and contains four minimal SH3 binding motifs (PXXP). We have demonstrated the importance of ORF I expression in the establishment of infection and hypothesize that p12I has a role in T-cell activation. In this study, we tested interleukin-2 (IL-2) receptor expression, IL-2-mediated proliferation, and Jak/Stat act...

  19. 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.

  20. Dimethylfumarate for psoriasis: Pronounced effects on lesional T-cell subsets, epidermal proliferation and differentiation, but not on natural killer T cells in immunohistochemical study.

    NARCIS (Netherlands)

    Bovenschen, H.J.; Langewouters, A.M.G.; Kerkhof, P.C.M. van de

    2010-01-01

    BACKGROUND: T-cell infiltration, epidermal hyperproliferation, and disturbed keratinization are pathologic hallmarks of plaque psoriasis. Oral fumaric acid esters are an effective therapy for psoriasis and are believed to exert their effects mainly through their anti-inflammatory properties. OBJECTI

  1. Implementation of exon arrays: alternative splicing during T-cell proliferation as determined by whole genome analysis

    Directory of Open Access Journals (Sweden)

    Whistler Toni

    2010-09-01

    Full Text Available Abstract Background The contribution of alternative splicing and isoform expression to cellular response is emerging as an area of considerable interest, and the newly developed exon arrays allow for systematic study of these processes. We use this pilot study to report on the feasibility of exon array implementation looking to replace the 3' in vitro transcription expression arrays in our laboratory. One of the most widely studied models of cellular response is T-cell activation from exogenous stimulation. Microarray studies have contributed to our understanding of key pathways activated during T-cell stimulation. We use this system to examine whole genome transcription and alternate exon usage events that are regulated during lymphocyte proliferation in an attempt to evaluate the exon arrays. Results Peripheral blood mononuclear cells form healthy donors were activated using phytohemagglutinin, IL2 and ionomycin and harvested at 5 points over a 7 day period. Flow cytometry measured cell cycle events and the Affymetrix exon array platform was used to identify the gene expression and alternate exon usage changes. Gene expression changes were noted in a total of 2105 transcripts, and alternate exon usage identified in 472 transcript clusters. There was an overlap of 263 transcripts which showed both differential expression and alternate exon usage over time. Gene ontology enrichment analysis showed a broader range of biological changes in biological processes for the differentially expressed genes, which include cell cycle, cell division, cell proliferation, chromosome segregation, cell death, component organization and biogenesis and metabolic process ontologies. The alternate exon usage ontological enrichments are in metabolism and component organization and biogenesis. We focus on alternate exon usage changes in the transcripts of the spliceosome complex. The real-time PCR validation rates were 86% for transcript expression and 71% for

  2. Defect density in multiwalled carbon nanotubes influences ovalbumin adsorption and promotes macrophage activation and CD4(+) T-cell proliferation.

    Science.gov (United States)

    Bai, Wei; Raghavendra, Achyut; Podila, Ramakrishna; Brown, Jared M

    2016-01-01

    Carbon nanotubes (CNTs) are of great interest for the development of drugs and vaccines due to their unique physicochemical properties. The high surface area to volume ratio and delocalized pi-electron cloud of CNTs promote binding of proteins to the surface forming a protein corona. This unique feature of CNTs has been recognized for potential delivery of antigens for strong and long-lasting antigen-specific immune responses. Based on an earlier study that demonstrated increased protein binding, we propose that carboxylated multiwalled CNTs (MWCNTs) can function as an improved carrier to deliver antigens such as ovalbumin (OVA). To test this hypothesis, we coated carboxylated MWCNTs with OVA and measured uptake and activation of antigen-presenting cells (macrophages) and their ability to stimulate CD4(+) T-cell proliferation. We employed two types of carboxylated MWCNTs with different surface areas and defects (MWCNT-2 and MWCNT-30). MWCNT-2 and MWCNT-30 have surface areas of ~215 m(2)/g and 94 m(2)/g, respectively. The ratios of D- to G-band areas (I D/I G) were 0.97 and 1.37 for MWCNT-2 and MWCNT-30, respectively, samples showing that MWCNT-30 contained more defects. The increase in defects in MWCNT-30 led to increased binding of OVA as compared to MWCNT-2 (1,066±182 μg/mL vs 582±41 μg/mL, respectively). Both types of MWCNTs, along with MWCNT-OVA complexes, showed no observable toxicity to bone-marrow-derived macrophages up to 5 days. Surprisingly, we found that MWCNT-OVA complex significantly increased the expression of major histocompatibility complex class II on macrophages and production of pro-inflammatory cytokines (tumor necrosis factor-α and interleukin 6), while MWCNTs without OVA protein corona did not. The coculture of MWCNT-OVA-complex-treated macrophages and OVA-specific CD4(+) T-cells isolated from OT-II mice demonstrated robust proliferation of CD4(+) T-cells. This study provides strong evidence for a role for defects in carboxylated MWCNTs

  3. Defect density in multiwalled carbon nanotubes influences ovalbumin adsorption and promotes macrophage activation and CD4+ T-cell proliferation

    Science.gov (United States)

    Bai, Wei; Raghavendra, Achyut; Podila, Ramakrishna; Brown, Jared M

    2016-01-01

    Carbon nanotubes (CNTs) are of great interest for the development of drugs and vaccines due to their unique physicochemical properties. The high surface area to volume ratio and delocalized pi-electron cloud of CNTs promote binding of proteins to the surface forming a protein corona. This unique feature of CNTs has been recognized for potential delivery of antigens for strong and long-lasting antigen-specific immune responses. Based on an earlier study that demonstrated increased protein binding, we propose that carboxylated multiwalled CNTs (MWCNTs) can function as an improved carrier to deliver antigens such as ovalbumin (OVA). To test this hypothesis, we coated carboxylated MWCNTs with OVA and measured uptake and activation of antigen-presenting cells (macrophages) and their ability to stimulate CD4+ T-cell proliferation. We employed two types of carboxylated MWCNTs with different surface areas and defects (MWCNT-2 and MWCNT-30). MWCNT-2 and MWCNT-30 have surface areas of ~215 m2/g and 94 m2/g, respectively. The ratios of D- to G-band areas (ID/IG) were 0.97 and 1.37 for MWCNT-2 and MWCNT-30, respectively, samples showing that MWCNT-30 contained more defects. The increase in defects in MWCNT-30 led to increased binding of OVA as compared to MWCNT-2 (1,066±182 μg/mL vs 582±41 μg/mL, respectively). Both types of MWCNTs, along with MWCNT–OVA complexes, showed no observable toxicity to bone-marrow-derived macrophages up to 5 days. Surprisingly, we found that MWCNT–OVA complex significantly increased the expression of major histocompatibility complex class II on macrophages and production of pro-inflammatory cytokines (tumor necrosis factor-α and interleukin 6), while MWCNTs without OVA protein corona did not. The coculture of MWCNT–OVA-complex-treated macrophages and OVA-specific CD4+ T-cells isolated from OT-II mice demonstrated robust proliferation of CD4+ T-cells. This study provides strong evidence for a role for defects in carboxylated MWCNTs and

  4. Pseudomonas aeruginosa quorum-sensing signal molecules interfere with dendritic cell-induced T-cell proliferation

    DEFF Research Database (Denmark)

    Skindersø, Mette Elena; Zeuthen, Louise; Pedersen, Susanne Brix;

    2009-01-01

    Pseudomonas aeruginosa releases a wide array of toxins and tissue-degrading enzymes. Production of these malicious virulence factors is controlled by interbacterial communication in a process known as quorum sensing. An increasing body of evidence reveals that the bacterial signal molecule N-(3-o......DHL and PQS thus seem to possess dual activities in the infection process: as inducers of virulence factors as well as immune-modulators facilitating the infective properties of this pathogen....

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

    Energy Technology Data Exchange (ETDEWEB)

    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.

  6. ESAT-6 Targeting to DEC205+ Antigen Presenting Cells Induces Specific-T Cell Responses against ESAT-6 and Reduces Pulmonary Infection with Virulent Mycobacterium tuberculosis.

    Directory of Open Access Journals (Sweden)

    Aarón Silva-Sánchez

    Full Text Available Airways infection with Mycobacterium tuberculosis (Mtb is contained mostly by T cell responses, however, Mtb has developed evasion mechanisms which affect antigen presenting cell (APC maturation/recruitment delaying the onset of Ag-specific T cell responses. Hypothetically, bypassing the natural infection routes by delivering antigens directly to APCs may overcome the pathogen's naturally evolved evasion mechanisms, thus facilitating the induction of protective immune responses. We generated a murine monoclonal fusion antibody (α-DEC-ESAT to deliver Early Secretory Antigen Target (ESAT-6 directly to DEC205+ APCs and to assess its in vivo effects on protection associated responses (IFN-γ production, in vivo CTL killing, and pulmonary mycobacterial load. Treatment with α-DEC-ESAT alone induced ESAT-6-specific IFN-γ producing CD4+ T cells and prime-boost immunization prior to Mtb infection resulted in early influx (d14 post-infection and increased IFN-γ+ production by specific T cells in the lungs, compared to scarce IFN-γ production in control mice. In vivo CTL killing was quantified in relevant tissues upon transferring target cells loaded with mycobacterial antigens. During infection, α-DEC-ESAT-treated mice showed increased target cell killing in the lungs, where histology revealed cellular infiltrate and considerably reduced bacterial burden. Targeting the mycobacterial antigen ESAT-6 to DEC205+ APCs before infection expands specific T cell clones responsible for early T cell responses (IFN-γ production and CTL activity and substantially reduces lung bacterial burden. Delivering mycobacterial antigens directly to APCs provides a unique approach to study in vivo the role of APCs and specific T cell responses to assess their potential anti-mycobacterial functions.

  7. A critical role of IFNγ in priming MSC-mediated suppression of T cell proliferation through up-regulation of B7-H1

    Institute of Scientific and Technical Information of China (English)

    2008-01-01

    Bone-marrow-derived mesenchymal stem cells (MSCs) have been shown to possess immunosuppressive properties, e.g., by inhibiting T cell proliferation. Activated T cells can also enhance the immunosuppression ability of MSCs. The precise mechanisms underlying MSC-mediated immunosuppression remain largely undefined, although both cell-cell contact and soluble factors have been implicated; nor is it clear how the immunosuppressive property of MSCs is modulated by T cells. Using MSCs isolated from mouse bone marrow, we show here that interferon gamma (IFNγ), a well-known proinflammatory cytokine produced by activated T cells, plays an important role in priming the immunosuppressive property of MSCs. Mechanistically, IFNγ acts directly on MSCs and leads to up-regulation of B7-H1, an inhibitory surface molecule in these stem cells. MSCs primed by activated T cells derived from IFNγ-/- mouse exhibited dramatically reduced ability to suppress T cell proliferation, a defect that can be rescued by supplying exogenous IFNy. Moreover, siRNA-mediated knockdown of B7-H1 in MSCs abolished immunosuppression by these cells. Taken together, our results suggest that IFNy plays a critical role in triggering the immunosuppresion by MSCs through upregulating B7-H1 in these cells, and provide evidence supporting the cell-cell contact mechanism in MSC-mediated immunosuppression.

  8. G0S2 modulates homeostatic proliferation of naïve CD8⁺ T cells and inhibits oxidative phosphorylation in mitochondria.

    Science.gov (United States)

    Lee, Ping-Hsien; Yamada, Takeshi; Park, Chun Shik; Shen, Ye; Puppi, Monica; Lacorazza, H Daniel

    2015-08-01

    Since its discovery, diverse functions have been attributed to the G0/G1 switch gene 2 (G0S2), from lipid metabolism to control of cell proliferation. Our group showed for the first time that G0S2 promotes quiescence in hematopoietic stem cells by interacting with and retaining nucleolin around the nucleus. Herein, we report the role of G0S2 in the differentiation and function of CD8(+) T cells examined in mice with an embryonic deletion of the G0s2 gene. G0S2 expression in naïve CD8(+) T cells decreased immediately after T-cell receptor activation downstream of the mitogen-activated protein kinase, calcium/calmodulin, phosphatidylinositol 3'-kinase and mammalian target of rapamycin pathways. Surprisingly, G0S2-null naïve CD8(+) T cells displayed increased basal and spare respiratory capacity that was not associated with increased mitochondrial biogenesis but with increased phosphorylation of AMP-activated protein kinase α. Naïve CD8(+) T cells showed increased proliferation in response to in vitro activation and in vivo lymphopenia; however, naïve CD8(+) T cells expressing the OT-1 transgene exhibited normal differentiation of naïve cells to effector and memory CD8(+) T cells upon infection with Listeria monocytogenes in a wild-type or a G0s2-null environment, with increased circulating levels of free fatty acids. Collectively, our results suggest that G0S2 inhibits energy production by oxidative phosphorylation to fine-tune proliferation in homeostatic conditions. PMID:25666096

  9. The effect of beta-interferon therapy on myelin basic protein-elicited CD4+ T cell proliferation and cytokine production in multiple sclerosis

    DEFF Research Database (Denmark)

    Hedegaard, Chris J; Krakauer, Martin; Bendtzen, Klaus;

    2008-01-01

    Interferon (IFN)-beta therapy has well-established clinical benefits in multiple sclerosis (MS), but the underlying modulation of cytokine responses to myelin self-antigens remains poorly understood. We analysed the CD4+ T cell proliferation and cytokine responses elicited by myelin basic protein...

  10. Research Note Mesenchymal stem cells from skin lesions of psoriasis patients promote proliferation and inhibit apoptosis of HaCaT cells.

    Science.gov (United States)

    Liu, R F; Wang, F; Wang, Q; Zhao, X C; Zhang, K M

    2015-12-22

    Psoriasis is an inflammatory skin disease characterized by excessive proliferation and abnormal differentiation and apoptosis of keratinocytes (KCs). Mesenchymal stem cells (MSCs) from skin lesions of psoriasis patients demonstrate abnormal cytokine secretion, which may affect KC proliferation and apoptosis. Here, we explored how MSCs from skin lesions of psoriasis patients affect HaCaT cell proliferation and apoptosis. First, flow cytometry and multipotent differentiation methods were used to identify skin MSCs, which were then co-cultured with HaCaT cells. HaCaT cell proliferation was analyzed in real-time, and cell cycle progression and apoptosis were assessed by flow cytometry. Cell morphologies and multipotencies of skin MSCs were similar between the psoriasis group and healthy control group, with high levels of CD29, CD44, CD73, CD90, and CD105 and limited expression of CD34, CD45, and HLA-DR. MSCs from skin lesions of psoriasis patients promote KC proliferation more potently and are less capable of inducing KC apoptosis. This may underlie KC proliferation and abnormal apoptosis in psoriasis skin lesions, which results in abnormal thickening of the epidermis.

  11. T Cells

    Science.gov (United States)

    T Cells - National Multiple Sclerosis Society Skip to navigation Skip to content Menu Navigation National Multiple Sclerosis Society Sign ... Is MS? Definition of MS T Cells T Cells Share Smaller Text Larger Text Print In this ...

  12. 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.

  13. 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

  14. Savinin, a lignan from Pterocarpus santalinus inhibits tumor necrosis factor-alpha production and T cell proliferation.

    Science.gov (United States)

    Cho, J Y; Park, J; Kim, P S; Yoo, E S; Baik, K U; Park, M H

    2001-02-01

    Two lignans were isolated from the heartwood of Pterocarpus santalinus by activity-guided fractionation and investigated for their biological properties and molecular mechanism of action. On the basis of their spectroscopic data, these compounds were identified as savinin (1) and calocedrin (2), dibenzyl butyrolactone-type lignan compounds having an alpha-arylidene gamma-lactone structure. These lignans significantly inhibited tumor necrosis factor (TNF)-a production in lipopolysaccharide (LPS)-stimulated RAW264.7 cells, and T cell proliferation elicited by concanavalin (Con A), without displaying cytotoxicity. The molecular inhibitory mechanism of compound 1 was confirmed to be mediated by the non-polar butyrolactone ring, according to a structure-relationship study with structurally related and unrelated compounds, such as arctigenin (a dibenzyl butyrolactone type lignan), eudesmin (a furofuran type lignan), isolariciresinol (a dibenzylbutane type lignan), and cynaropicrin (a sesquiterpene lactone). The results suggest that savinin may act as an active principle in the reported biological activities of P. santalinus, such as antiinflammatory effect, by mediation of the butyrolactone ring as a valuable pharmacophore. PMID:11217086

  15. Depletion of Regulatory T Cells Induces High Numbers of Dendritic Cells and Unmasks a Subset of Anti-Tumour CD8+CD11c+ PD-1lo Effector T Cells.

    Directory of Open Access Journals (Sweden)

    Nicolas Goudin

    Full Text Available Natural regulatory T (Treg cells interfere with multiple functions, which are crucial for the development of strong anti-tumour responses. In a model of 4T1 mammary carcinoma, depletion of CD25+Tregs results in tumour regression in Balb/c mice, but the mechanisms underlying this process are not fully understood. Here, we show that partial Treg depletion leads to the generation of a particular effector CD8 T cell subset expressing CD11c and low level of PD-1 in tumour draining lymph nodes. These cells have the capacity to migrate into the tumour, to kill DCs, and to locally regulate the anti-tumour response. These events are concordant with a substantial increase in CD11b+ resident dendritic cells (DCs subsets in draining lymph nodes followed by CD8+ DCs. These results indicate that Treg depletion leads to tumour regression by unmasking an increase of DC subsets as a part of a program that optimizes the microenvironment by orchestrating the activation, amplification, and migration of high numbers of fully differentiated CD8+CD11c+PD1lo effector T cells to the tumour sites. They also indicate that a critical pattern of DC subsets correlates with the evolution of the anti-tumour response and provide a template for Treg depletion and DC-based therapy.

  16. Depletion of Regulatory T Cells Induces High Numbers of Dendritic Cells and Unmasks a Subset of Anti-Tumour CD8+CD11c+ PD-1lo Effector T Cells.

    Science.gov (United States)

    Goudin, Nicolas; Chappert, Pascal; Mégret, Jérome; Gross, David-Alexandre; Rocha, Benedita; Azogui, Orly

    2016-01-01

    Natural regulatory T (Treg) cells interfere with multiple functions, which are crucial for the development of strong anti-tumour responses. In a model of 4T1 mammary carcinoma, depletion of CD25+Tregs results in tumour regression in Balb/c mice, but the mechanisms underlying this process are not fully understood. Here, we show that partial Treg depletion leads to the generation of a particular effector CD8 T cell subset expressing CD11c and low level of PD-1 in tumour draining lymph nodes. These cells have the capacity to migrate into the tumour, to kill DCs, and to locally regulate the anti-tumour response. These events are concordant with a substantial increase in CD11b+ resident dendritic cells (DCs) subsets in draining lymph nodes followed by CD8+ DCs. These results indicate that Treg depletion leads to tumour regression by unmasking an increase of DC subsets as a part of a program that optimizes the microenvironment by orchestrating the activation, amplification, and migration of high numbers of fully differentiated CD8+CD11c+PD1lo effector T cells to the tumour sites. They also indicate that a critical pattern of DC subsets correlates with the evolution of the anti-tumour response and provide a template for Treg depletion and DC-based therapy. PMID:27341421

  17. 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.

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

    International Nuclear Information System (INIS)

    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

  19. Loss of CAR promotes migration and proliferation of HaCaT cells, and accelerates wound healing in rats via Src-p38 MAPK pathway

    Science.gov (United States)

    Su, Linlin; Fu, Lanqing; Li, Xiaodong; Zhang, Yue; Li, Zhenzhen; Wu, Xue; Li, Yan; Bai, Xiaozhi; Hu, Dahai

    2016-01-01

    The coxsackie and adenovirus receptor (CAR) is a cell adhesion molecule mostly localized to cell-cell contacts in epithelial and endothelial cells. CAR is known to regulate tumor progression, however, its physiological role in keratinocyte migration and proliferation, two essential steps in re-epithelialization during wound healing, has less been investigated. Here we showed that CAR was predominantly expressed in the epidermis of human skin, CAR knockdown by RNAi significantly accelerated HaCaT cell migration and proliferation. In addition, knockdown of CAR in vitro increased p-Src, p-p38, and p-JNK protein levels; however, Src inhibitor PP2 prevented the increase of p-Src and p-p38 induced by CAR RNAi, but not p-JNK, and decelerated cell migration and proliferation. More intriguingly, in vivo CAR RNAi on the skin area surrounding the wounds on rat back visually accelerated wound healing and re-epithelialization process, while treatment with PP2 or p38 inhibitor SB203580 obviously inhibited these effects. By contrast, overexpressing CAR in HaCaT cells significantly decelerated cell migration and proliferation. Above results demonstrate that suppression of CAR could accelerate HaCaT cell migration and proliferation, and promote wound healing in rat skin, probably via Src-p38 MAPK pathway. CAR thus might serve as a novel therapeutic target for facilitating wound healing. PMID:26804208

  20. Basis for defective proliferation of peripheral blood T cells to anti-CD2 antibodies in primary Sjögren's syndrome.

    Science.gov (United States)

    Gerli, R; Bertotto, A; Agea, E; Lanfrancone, L; Cernetti, C; Spinozzi, F; Rambotti, P

    1990-12-01

    Anti-CD2-induced T cell proliferation was analyzed in the peripheral blood samples of 31 primary and 8 secondary untreated Sjögren's syndrome patients. Anti-CD2-stimulated PBMC proliferation was very low in about one-third of primary Sjögren's syndrome samples, despite the number of CD2+ cells being similar in primary and secondary Sjögren's syndrome and normal PBMC samples. The depressed response to anti-CD2 was mainly found in anti-Ro+/La+ patients. Experiments on purified T cells demonstrated that a defect at the T cell level was responsible for the anti-CD2 unresponsiveness. Cell proliferation failure was associated with poor IL-2 and IL-2 receptor mRNA expression and, consequently, IL-2 and IL-2 receptor synthesis. Since defective anti-CD2-induced mitogenesis could be reversed by phorbol myristate acetate, but not calcium ionophore A23187, it is probably correlated with impaired protein kinase C activation. Comparison of anti-CD2-triggered PBMC proliferation in treated and untreated patients and a long-term study of nine patients showed that the defect is a stable characteristic in primary Sjögren's syndrome patients, but that it can be reversed by pharmacological immunosuppression. PMID:1979333

  1. SHIP-deficient dendritic cells, unlike wild type dendritic cells, suppress T cell proliferation via a nitric oxide-independent mechanism.

    Directory of Open Access Journals (Sweden)

    Frann Antignano

    Full Text Available BACKGROUND: Dendritic cells (DCs not only play a crucial role in activating immune cells but also suppressing them. We recently investigated SHIP's role in murine DCs in terms of immune cell activation and found that TLR agonist-stimulated SHIP-/- GM-CSF-derived DCs (GM-DCs were far less capable than wild type (WT, SHIP+/+ GM-DCs at activating T cell proliferation. This was most likely because SHIP-/- GM-DCs could not up-regulate MHCII and/or co-stimulatory receptors following TLR stimulation. However, the role of SHIP in DC-induced T cell suppression was not investigated. METHODOLOGY/PRINCIPAL FINDINGS: In this study we examined SHIP's role in DC-induced T cell suppression by co-culturing WT and SHIP-/- murine DCs, derived under different conditions or isolated from spleens, with αCD3+ αCD28 activated WT T cells and determined the relative suppressive abilities of the different DC subsets. We found that, in contrast to SHIP+/+ and -/- splenic or Flt3L-derived DCs, which do not suppress T cell proliferation in vitro, both SHIP+/+ and -/- GM-DCs were capable of potently suppressing T cell proliferation. However, WT GM-DC suppression appeared to be mediated, at least in part, by nitric oxide (NO production while SHIP-/- GM-DCs expressed high levels of arginase 1 and did not produce NO. Following exhaustive studies to ascertain the mechanism of SHIP-/- DC-mediated suppression, we could conclude that cell-cell contact was required and the mechanism may be related to their relative immaturity, compared to SHIP+/+ GM-DCs. CONCLUSIONS: These findings suggest that although both SHIP+/+ and -/- GM-DCs suppress T cell proliferation, the mechanism(s employed are different. WT GM-DCs suppress, at least in part, via IFNγ-induced NO production while SHIP-/- GM-DCs do not produce NO and suppression can only be alleviated when contact is prevented.

  2. Giardia duodenalis stimulates partial maturation of bovine dendritic cells associated with altered cytokine secretion and induction of T-cell proliferation.

    Science.gov (United States)

    Grit, G H; Devriendt, B; Van Coppernolle, S; Geurden, T; Hope, J; Vercruysse, J; Cox, E; Geldhof, P; Claerebout, E

    2014-04-01

    Giardia duodenalis is an important intestinal parasite in animals and humans. The role of dendritic cells (DC) in the initiation of the immune response against G. duodenalis is poorly documented. The aim of this study was to test the hypothesis that G. duodenalis interferes with bovine DC function. Therefore, the effect of trophozoites and excretion/secretion products on bovine monocyte-derived dendritic cells (MoDC) was investigated. We assessed MoDC maturation and cytokine production of G. duodenalis-stimulated MoDC and the ability of these MoDC to take up antigen and induce lymphocyte proliferation. Little or no upregulation of maturation markers CD40 and CD80 was measured, but MHCII expression was increased after stimulation with low parasite concentrations. A dose-dependent decrease in ovalbumin uptake was observed in G. duodenalis-stimulated MoDC. In addition, stimulated MoDC induced proliferation of CD3(-) , γδ-T-cells and TCRαβ(+) CD4(+) and CD8(+) T-cells. Increased transcription of TGF-β was shown in CD4(+) T cells, and increased TNF-α, TGF-β, IL-10 and IL-4 were seen in γδ-T-cells. We found no evidence that G. duodenalis has a regulatory or inhibitory effect on bovine MoDC. MoDC stimulated with G. duodenalis are functionally active and able to induce proliferation of T cells that produce both pro- and anti-inflammatory cytokines.

  3. Antigen-dependent proliferation and cytokine induction in respiratory syncytial virus-infected cotton rats reflect the presence of effector-memory T cells

    International Nuclear Information System (INIS)

    Respiratory syncytial virus (RSV) is a major cause of lower airway disease in infants and children. Immunity to RSV is not long lasting, resulting in re-occurring infections throughout life. Effective long-lived immunity results when central-memory T cells that proliferate vigorously and secrete IL-2 are present. In contrast, effector-memory T cells that mainly produce IFN-γ, facilitate virus clearance but are not long lived. To identify the type of memory response induced after RSV-A (Long) infection, we characterized the kinetics of the antigen-specific immune response and identified the types of cytokines induced. RSV-specific lymphocytic proliferation following primary and secondary infection was similar, and in both cases responses waned within a short period of time. In addition, mRNA for IFN-γ but not IL-2 was induced in RSV-specific CD4+ T cells. This supports the idea that the presence of effector-memory rather than central-memory T cells contributes to the ineffectiveness of the immune response to RSV

  4. Regulatory T cell suppressive potency dictates the balance between bacterial proliferation and clearance during persistent Salmonella infection.

    Directory of Open Access Journals (Sweden)

    Tanner M Johanns

    Full Text Available The pathogenesis of persistent infection is dictated by the balance between opposing immune activation and suppression signals. Herein, virulent Salmonella was used to explore the role and potential importance of Foxp3-expressing regulatory T cells in dictating the natural progression of persistent bacterial infection. Two distinct phases of persistent Salmonella infection are identified. In the first 3-4 weeks after infection, progressively increasing bacterial burden was associated with delayed effector T cell activation. Reciprocally, at later time points after infection, reductions in bacterial burden were associated with robust effector T cell activation. Using Foxp3(GFP reporter mice for ex vivo isolation of regulatory T cells, we demonstrate that the dichotomy in infection tempo between early and late time points is directly paralleled by drastic changes in Foxp3(+ Treg suppressive potency. In complementary experiments using Foxp3(DTR mice, the significance of these shifts in Treg suppressive potency on infection outcome was verified by enumerating the relative impacts of regulatory T cell ablation on bacterial burden and effector T cell activation at early and late time points during persistent Salmonella infection. Moreover, Treg expression of CTLA-4 directly paralleled changes in suppressive potency, and the relative effects of Treg ablation could be largely recapitulated by CTLA-4 in vivo blockade. Together, these results demonstrate that dynamic regulation of Treg suppressive potency dictates the course of persistent bacterial infection.

  5. The effect of vitamin A supplementation on stimulated T-cell proliferation with myelin oligodendrocyte glycoprotein in patients with multiple sclerosis

    OpenAIRE

    Sima Jafarirad; Fereydoon Siassi; Mohammad-Hossein Harirchian; Mohammad-Ali Sahraian; Mohammad-Reza Eshraghian; Fazel Shokri; Reza Amani; Sama Bitarafan; Sabah Mozafari; Aliakbar Saboor-Yaraghi

    2012-01-01

    Background: Multiple sclerosis (MS) is an autoimmune disease whereby myelin sheath of the central nervous system is destroyed. Vitamin A is known to play a role in the immune system. It has been recognized that some metabolites of vitamin A can be used effectively to treat experimental autoimmune encephalomyelitis (EAE). Aims: The effect of vitamin A as retinyl palmitate on T-cell proliferation in MS patients. Setting and Design: This study is a double blind clinical trial of two test groups ...

  6. Regulation of mitogen-stimulated human T-cell proliferation, interleukin-2 production, and interleukin-2 receptor expression by protein kinase C inhibitor, H-7

    Energy Technology Data Exchange (ETDEWEB)

    Atluru, D.; Polam, S.; Atluru, S. (Kansas State Univ., Manhattan (United States)); Woloschak, G.E. (Argonne National Lab., IL (United States))

    1990-01-01

    Recently published reports suggest that the activation of protein kinase C (PKC) plays an important role in the activation pathway of many cell types. In this study, the authors examined the role of PKC in human T-cell proliferation, IL-2 production, and IL-2R expression, when cultured with the mitogen PHA, the PKC inhibitor H-7, and H-7 control HA1004. H-7 inhibited the PHA-simulated ({sup 3}H)thymidine uptake, IL-2production, and IL-2R expression in a dose-related manner. Further, they found H-7 inhibited T-cell proliferation, IL-2 production, and IL-2mRNA from PHA plus PMA-stimulated cultures. They also found that H-7 inhibited the early-stage activation of PHA-stimulated cells. The presence of exogenous purified human IL-2 or rIL-4 partly reversed the immunosuppression caused by H-7. In contrast, HA1004 had no effect on cell proliferation, IL-2 production, or IL-2R expression. The results demonstrate that PKC activation is one major pathway through which T-cells become activated.

  7. Effect of All-Trans Retinoic Acid (ATRA on Viability, Proliferation, Activation and Lineage-Specific Transcription Factors of CD4+ T Cells

    Directory of Open Access Journals (Sweden)

    Katayoon Bidad

    2011-12-01

    Full Text Available All-trans retinoic acid (ATRA, as an active metabolite of vitamin A, has been shown to affect immune cells. This study was performed to evaluate the effect of ATRA on viability, proliferation, activation and lineage-specific transcription factors of CD4+ T cells. CD4+ T cells were  separated  from  heparinized  blood  of  healthy  donors  and  were  cultured  in conditions, some with, some without ATRA.Viability was assessed by PI  flowcytometry and proliferation was measured by MTT assay. CD69 expression was determined by flowcytometry as a measure of cell activation. Lineage-specific transcription  factors  (FOXP3,  RORγt  and  T-bet  were  examined  by intracellular staining and flowcytometry. High doses of ATRA (0.1-1 mM caused extensive cell death in both PBMCs and CD4+ T cells. Doses of ATRA equal to or lower than 10 µM did not  adversely affect cell viability and proliferation in comparison to  culture medium without ATRA.Doses of ATRA between 10 µM and 1nM significantly increased cell activation when compared  to  culture medium without  ATRA. ATRA could increase FOXP3+  and also FOXP3+RORγt+ T cells while it decreased RORγt+ and T-bet+ T cells. This study showed that doses of ATRA up to 10 µM are safe when using with CD4+  T cells in terms of cell viability, proliferation and activation.We  could  also  show  that  ATRA  diverts  the  human  immune  response  in  neutral conditions (without adding polarizing cytokines by increasing FOXP3+  cells and decreasing RORγt+  cells. ATRA could be regarded as a potential therapy in inflammatory conditions and autoimmunities.

  8. 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.)

  9. CTLA-4 is Required by CD4+CD25+ Treg to Control CD4+ T Cell Lymphopenia-Induced Proliferation

    OpenAIRE

    Sojka, Dorothy K.; Hughson, Angela; Fowell, Deborah J.

    2009-01-01

    CTLA-4 is constitutively expressed by CD4+CD25+Foxp3+ regulatory T cells (Treg) but its precise role in Treg function is not clear. Although blockade of CTLA-4 interferes with Treg function, studies using CTLA-4 deficient Treg have failed to reveal an essential requirement for CTLA-4 in Treg suppression in vivo. Conditional deletion of CTLA-4 in Foxp3+ T cells disrupts immune homeostasis in vivo but the immune processes disrupted by CTLA-4 deletion have not been determined. We demonstrate tha...

  10. 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...

  11. Transforming growth factor-beta inhibits human antigen-specific CD4(+) T cell proliferation without modulating the cytokine response

    NARCIS (Netherlands)

    Tiemessen, MM; Kunzmann, S; Schmidt-Weber, CB; Garssen, J; Bruijnzeel-Koomen, CAFM; Knol, EF; Van Hoffen, E

    2003-01-01

    Transforming growth factor (TGF)-beta has been demonstrated to play a key role in the regulation of the immune response, mainly by its suppressive function towards cells of the immune system. In humans, the effect of TGF-beta on antigen-specific established memory T cells has not been investigated y

  12. Genetic evidence that intratumoral T-cell proliferation and activation are associated with recurrence and survival in patients with resected colorectal liver metastases.

    Science.gov (United States)

    Maker, Ajay V; Ito, Hiromichi; Mo, Qianxing; Weisenberg, Elliot; Qin, Li-Xuan; Turcotte, Simon; Maithel, Shishir; Shia, Jinru; Blumgart, Leslie; Fong, Yuman; Jarnagin, William R; DeMatteo, Ronald P; D'Angelica, Michael I

    2015-04-01

    Though immune responses correlate with prognosis in primary colorectal cancer, the role of tumor immunity in metastatic disease is less clear. We hypothesized that patient survival and tumor recurrence correlate with transcriptional evidence of lymphocyte proliferation/activation in resected colorectal cancer liver metastases (CRLM). Microarray gene analysis was performed on liver tumor specimens from 96 patients who underwent resection for CRLM. A Cox proportional hazards model identified genes associated with overall survival (OS) and recurrence-free survival (RFS). Conventional gene ontology (GO) enrichment analysis ranked biologically relevant processes. Survival probabilities of prioritized processes were assessed. Protein expression was validated with immunohistochemistry in an independent set of patients. GO analysis identified and ranked unique biologic processes that correlated with survival. Genes that specifically functioned in the biologic process of "T-cell proliferation" were significant predictors of OS (P = 0.01), and both "T-cell proliferation" and "activation" were highly associated with RFS (P ≤ 0.01). Analysis of genes in these GO categories identified increased TNFSF14/LIGHT expression to be most associated with improved OS and RFS (P ≤ 0.0006). Immunohistochemistry of an independent validation set of CRLM confirmed that both increased tumor-infiltrating lymphocytes (TIL) and higher LIGHT expression on TILs were associated with improved OS and RFS. Differential expression of genes involved in T-cell proliferation/activation was associated with survival outcomes in a large number of surgical patients who underwent resection of CRLM. These biologic functions determined by GO analysis of the tumor microenvironment have identified specific immune-related genes that may be involved in an antitumor immune response. PMID:25600439

  13. Effects of pinacidil on proliferation of cultured rabbit airway smooth muscle cells induced by endothelin-1

    Institute of Scientific and Technical Information of China (English)

    WANG Hong; XIE Wei-ping; QI Xu; ZHANG Xi-long

    2005-01-01

    @@ It has been found that the potassium channel dysfunction of the membrane of airway smooth muscle cells (ASMCs) is closely associated with proliferation of ASMCs.1 Preliminary research has demonstrated that pinacidil, an ATP sensitive potassium channel (KATP) opener, could play a remarkable role in the prevention and treatment of antigen induced bronchial asthma in guinea pigs.2 This study was designed to investigate further the role and molecular mechanism of the proliferation of ASMCs: a chief pathological change of the nonacute phase of bronchial asthmatic episodes.

  14. Mushroom acidic glycosphingolipid induction of cytokine secretion from murine T cells and proliferation of NK1.1 α/β TCR-double positive cells in vitro

    International Nuclear Information System (INIS)

    Interferon (IFN)-γ and interleukin (IL)-4 regulate many types of immune responses. Here we report that acidic glycosphingolipids (AGLs) of Hypsizigus marmoreus and Pleurotus eryngii induced secretion of IFN- γ and IL-4 from T cells in a CD11c-positive cell-dependent manner similar to that of α-galactosylceramide (α-GalCer) and isoglobotriaosylceramide (iGb3), although activated T cells by AGLs showed less secretion of cytokine than those activated by α-GalCer. In addition, stimulation of these mushroom AGLs induced proliferation of NK1.1 α/β TCR-double positive cells in splenocytes. Administration of a mixture of α-GalCer and AGLs affected the stimulation of α-GalCer and generally induced a subtle Th1 bias for splenocytes but induced an extreme Th2 bias for thymocytes. These results suggested that edible mushroom AGLs contribute to immunomodulation

  15. Activation of CD1d-restricted natural killer T cells can inhibit cancer cell proliferation during chemotherapy by promoting the immune responses in murine mesothelioma.

    Science.gov (United States)

    Wu, Licun; Yun, Zhihong; Tagawa, Tetsuzo; De la Maza, Luis; Wu, Matthew Onn; Yu, Julie; Zhao, Yidan; de Perrot, Marc

    2014-12-01

    We studied the impact of natural killer T (NKT) cell activation by alpha-galactocysylceramide (α-GalCer, α-GC) on cancer cell repopulation during chemotherapy in murine mesothelioma. The number of NKT cells was found to be increased during the development of murine mesothelioma. NKT cells specifically recognize α-GC through CD1d resulting in their activation and expansion. Tumor-bearing mice were treated with chemotherapy once weekly, and α-GC was followed after each cycle of chemotherapy. Anti-tumor effect was evaluated on wild-type (WT) and CD1d knockout (CD1dKO) mice. Cancer cell proliferation and apoptosis were evaluated by Ki67 and TUNEL immunohistochemistry. CD4(+) and CD8(+) T cell proportion and activation in tumor, spleen, draining lymph node and peripheral blood were determined by flow cytometry, and gene expression of activated T cell-related cytokines was quantified by reverse transcription PCR. NKT cells were identified by CD1d-α-GC-tetramer staining. In WT mice, tumor growth delay was achieved by cisplatin (Cis), and this effect was improved in combination with α-GC, but α-GC alone had little effect. Cancer cell proliferation during chemotherapy was significantly inhibited by α-GC, while cancer cell death was significantly upregulated. α-GC following chemotherapy resulted in NKT cell expansion and an increase of interferon-γ production in the draining lymph node, blood and spleen. Gene expression of immune-associated cytokines was upregulated. Strikingly, the percentage of inducible T cell co-stimulator(+)CD4 T cells, Th17/Tc17 cells increased in splenocytes. In CD1d KO mice, however, Cis alone was less effective and Cis + α-GC provided no additional benefit over Cis alone. α-GC alone had minimal effect in both mice. NKT activation between cycles of chemotherapy could improve the outcome of mesothelioma treatment. PMID:25183171

  16. mTOR Inhibition Attenuates Dextran Sulfate Sodium-Induced Colitis by Suppressing T Cell Proliferation and Balancing TH1/TH17/Treg Profile.

    Directory of Open Access Journals (Sweden)

    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.

  17. Selective differentiation and proliferation of hematopoietic cells induced by recombinant human interleukins.

    OpenAIRE

    Saito, H; Hatake, K.; Dvorak, A. M.; Leiferman, K M; Donnenberg, A D; Arai, N.; Ishizaka, K; Ishizaka, T

    1988-01-01

    Effects of recombinant human interleukins on hematopoiesis were explored by using suspension cultures of mononuclear cells of human umbilical-cord blood and bone marrow. The results showed that interleukin 5 induced the selective differentiation and proliferation of eosinophils. After 3 weeks in culture with interleukin 5, essentially all nonadherent cells in both bone marrow and cord blood cell cultures became eosinophilic myelocytes. Culture of the same cells with interleukin 4 resulted in ...

  18. Prostaglandin E2 potentiates mesenchymal stem cell-induced IL-10+IFN-γ+CD4+ regulatory T cells to control transplant arteriosclerosis.

    Science.gov (United States)

    Hsu, Wan-Tseng; Lin, Cheng-Hsin; Chiang, Bor-Luen; Jui, Hsiang-Yiang; Wu, Kenneth Kun-Yu; Lee, Chii-Ming

    2013-03-01

    Mesenchymal stem cells (MSCs) are known for their immunomodulatory functions. We previously demonstrated that bone marrow-derived MSCs effectively control transplant arteriosclerosis (TA) by enhancing IL-10(+) and IFN-γ(+) cells. The objective of this study is to elucidate the mechanism by which MSCs induce IL-10(+)IFN-γ(+)CD4(+) regulatory T type 1 (T(R)1)-like cells. In an MLR system using porcine PBMCs, MSC-induced IL-10(+)IFN-γ(+)CD4(+) cells, which confer resistance to allogeneic proliferation in an IL-10-dependent manner, resemble T(R)1-like cells. Both cyclooxygenase-derived PGE(2) and IDO help to induce T(R)1-like cells by MSCs. MSCs constitutively secrete PGE(2), which is augmented in allogeneic reactions. However, T(R)1-like cells were deficient in PGE(2) and 4-fold less potent than were MSCs in suppressing MLR. PGE(2) mimetic supplements can enhance the immunosuppressive potency of T(R)1-like cells. In a porcine model of allogeneic femoral arterial transplantation, MSC-induced T(R)1-like cells combined with PGE(2), but not either alone, significantly reduced TA at the end of 6 wk (percentage of luminal area stenosis: T(R)1-like cells + PGE(2): 11 ± 10%; PGE(2) alone: 93 ± 8.7%; T(R)1-like cells alone: 88 ± 2.4% versus untreated 94 ± 0.9%, p < 0.001). These findings indicate that PGE(2) helps MSC-induced IL-10(+)IFN-γ(+)CD4(+) T(R)1-like cells inhibit TA. PGE(2) combined with MSC-induced T(R)1-like cells represents a new approach for achieving immune tolerance.

  19. Modulation of T cell proliferation and cytokine response by Plumbagin, extracted from Plumbago zeylanica in collagen induced arthritis

    OpenAIRE

    Poosarla Aparanji; DN, Rao; Athota Rama; Sunkara Venu

    2011-01-01

    Abstract Background The extracts of Plumbago zeylanica have been used in China and other Asian countries as folk medicine for the treatment of cancer, rheumatoid arthritis and dysmenorrhoea. Effect of Plumbagin (5-hydroxy-2-methyl-1,4-naphthoquinone) purified from Plumbago zeylanica on Con A induced T cell proliferation was studied in spleen cells from collagen induced arthritic DBA/1 mice. Methods The DBA/1 mice (five per each group) were immunized with 0.1 mL of collagen (emulsified in CFA)...

  20. Cytotoxicity and Proliferation Studies with Arsenic in Established Human Cell Lines: Keratinocytes, Melanocytes, Dendritic Cells, Dermal Fibroblasts, Microvascular Endothelial Cells, Monocytes and T-Cells

    Directory of Open Access Journals (Sweden)

    Hari H. P. Cohly

    2003-01-01

    Full Text Available Abstract: Based on the hypothesis that arsenic exposure results in toxicity and mitogenecity, this study examined the dose-response of arsenic in established human cell lines of keratinocytes (HaCaT, melanocytes (1675, dendritic cells (THP-1/A23187, dermal fibroblasts (CRL1904, microvascular endothelial cells (HMEC, monocytes (THP-1, and T cells (Jurkat. Cytotoxicity was determined by incubating THP-1, THP-1+ A23187 and JKT cells in RPMI 1640, 1675 in Vitacell, HMEC in EBM, and dermal fibroblasts and HaCaT in DMEM with 10% fetal bovine serum, 1% streptomycin and penicillin for 72 hrs in 96-well microtiter plates, at 37oC in a 5% CO2 incubator with different concentrations of arsenic using fluorescein diacetate (FDA. Cell proliferation in 96-well plates was determined in cultured cells starved by prior incubation for 24 hrs in 1% FBS and exposed for 72 hours, using the 96 cell titer proliferation solution (Promega assay. Cytotoxicity assays yielded LD50s of 9 μg/mL for HaCaT, 1.5 μg/mL for CRL 1675, 1.5 μg/mL for dendritic cells, 37 μg/mL for dermal fibroblasts, 0.48 μg/mL for HMEC, 50 μg/mL for THP-1 cells and 50 μg/mL for JKT-T cells. The peak proliferation was observed at 6 μg/mL for HaCaT and THP-1 cells, 0.19 μg/mL for CRL 1675, dendritic cells, and HMEC, and 1.5 μg/mL for dermal fibroblasts and Jurkat T cells. These results show that arsenic is toxic at high doses to keratinocytes, fibroblasts, monocytes and T cells, and toxic at lower doses to melanocytes, microvascular endothelial cells and dendritic cells. Proliferation studies showed sub-lethal doses of arsenic to be mitogenic.

  1. Dasatinib inhibits proliferation and activation of CD8+ T-lymphocytes by down-regulation of the T-cell receptor signaling

    OpenAIRE

    Fei, Fei

    2007-01-01

    The novel Src/Abl inhibitor dasatinib (BMS-354825) is a promising therapeutic agent with imatinib-resistant BCR-ABL mutations in patients with chronic myelogenous leukemia (CML) or Ph-positive acute lymphoblastic leukemia (ALL). However, little is known about its effects on T-cell function, especially for patients undergoing allogeneic transplantation for leukemia. Here, we demonstrate that dasatinib at a concentration of 5 nM to 250 nM inhibits the proliferation and activation of CD8+ T-lymp...

  2. The signal transduction pathway in the proliferation of airway smooth muscle cells induced by urotensin Ⅱ

    Institute of Scientific and Technical Information of China (English)

    陈亚红; 赵鸣武; 姚婉贞; 庞永政; 唐朝枢

    2004-01-01

    Background Human urotensin Ⅱ (UⅡ) is the most potent mammalian vasoconstrictor identified so far. Our previous study showed that UⅡ is a potent mitogen of airway smooth muscle cells (ASMC) inducing ASMC proliferation in a dose-dependent manner. The signal transduction pathway of UⅡ mitogenic effect remains to be clarified. This study was conducted to investigate the signal transduction pathway in the proliferation of ASMC induced by UⅡ.Methods In primary cultures of rat ASMCs, activities of protein kinase C (PKC), mitogen-activated protein kinase (MAPK) and calcineurin (CaN) induced by UⅡ were measured. The effect of CaN on PKC and MAPK was studied by adding cyclosporin A (CsA), a specific inhibitor of CaN. Using H7 and PD98059, inhibitors of PKC and MAPK, respectively, to study the effect of PKC and MAPK on CaN. The cytosolic free calcium concentration induced by UⅡ was measured using Fura-2/AM. Results UⅡ 10-7 mol/L stimulated ASMC PKC and MAPK activities by 44% and 24% (P0.05). CsA 10-6 mol/L inhibited UⅡ-stimulated PKC activity by 14% (P0.05).Conclusions UⅡ increases cytosolic free calcium concentration and activates PKC, MAPK and CaN. The signal transduction pathway between PKC and CaN has cross-talk.

  3. Accelerated in vivo proliferation of memory phenotype CD4+ T-cells in human HIV-1 infection irrespective of viral chemokine co-receptor tropism.

    Directory of Open Access Journals (Sweden)

    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.

  4. Calcineurin/nuclear factor of activated T cells-coupled vanilliod transient receptor potential channel 4 ca2+ sparklets stimulate airway smooth muscle cell proliferation.

    Science.gov (United States)

    Zhao, Limin; Sullivan, Michelle N; Chase, Marlee; Gonzales, Albert L; Earley, Scott

    2014-06-01

    Proliferation of airway smooth muscle cells (ASMCs) contributes to the remodeling and irreversible obstruction of airways during severe asthma, but the mechanisms underlying this disease process are poorly understood. Here we tested the hypothesis that Ca(2+) influx through the vanilliod transient receptor potential channel (TRPV) 4 stimulates ASMC proliferation. We found that synthetic and endogenous TRPV4 agonists increase proliferation of primary ASMCs. Furthermore, we demonstrate that Ca(2+) influx through individual TRPV4 channels produces Ca(2+) microdomains in ASMCs, called "TRPV4 Ca(2+) sparklets." We also show that TRPV4 channels colocalize with the Ca(2+)/calmodulin-dependent protein phosphatase calcineurin in ASMCs. Activated calcineurin dephosphorylates nuclear factor of activated T cells (NFAT) transcription factors cytosolic (c) to allow nuclear translocation and activation of synthetic transcriptional pathways. We show that ASMC proliferation in response to TRPV4 activity is associated with calcineurin-dependent nuclear translocation of the NFATc3 isoform tagged with green florescent protein. Our findings suggest that Ca(2+) microdomains created by TRPV4 Ca(2+) sparklets activate calcineurin to stimulate nuclear translocation of NFAT and ASMC proliferation. These findings further suggest that inhibition of TRPV4 could diminish asthma-induced airway remodeling.

  5. NK/T细胞淋巴瘤细胞凋亡和细胞增殖特征及意义%The significance and features of apoptosis and proliferation of NK/T cell lymphoma

    Institute of Scientific and Technical Information of China (English)

    Dabin Wang; Meng Ming; Junhua Liu; Jianhua Yi; Dianding Zou

    2011-01-01

    Objective:The aim was to study the features and clinical significance of cell apoptosis and proliferation of NK/T cell lymphoma. Methods:TdT-mediated dUTP nick end labeling and immunohistochemical Streptavidin-peroxidase method were used to study cell apoptosis and the expression of proliferation cell nuclear antigen in 25 NK/T cell lymphoma and 10reactive lymphoid tissues. Results:Apoptotic index (AI) and proliferative index (PI) averaged (1.92% ± 0.86%) and (41.48%± 5.10%) respectively in the 25 NK/T cell lymphomas and (6.70% ± 1.89%) and (20.10% ± 2.77%) in the 10 reactive lymphoid tissues. Compared with reactive lymphoid tissues, AI was significantly reduced in NK/T cell lymphoma (t = 10.80, P < 0.01)while PI significantly increased (t = 12.39, P < 0.01). In addition, in NK/T cell lymphoma, AI and PI were positively related (r = 0.69, P < 0.01). Conclusion:In NK/T cell lymphoma, cell apoptosis is reduced while cell proliferation increased. The imbalance between cell apoptosis and cell proliferation is closely related to the development and progression of NK/T cell lymphoma.

  6. Exosomes derived from renal cancer cells induce Jurkat T cell apoptosis in vitro%肾癌细胞来源的exosomes诱导Jurkat T细胞凋亡

    Institute of Scientific and Technical Information of China (English)

    杨林; 吴小候; 罗春丽; 王丹; 陈力学

    2013-01-01

    Objective To investigate the underlying mechanism of exosomes derived from renal cancer cell lines 786-0 to mediate tumor immune escape in vitro. Methods CCK-8 assay was used to determine the effects of exosomes on proliferation in Jurkat T cells. Morphological changes were by wright-giemsa staining;flow cytometry with Annexin V-FITC/PI double staining was used to detect the apoptosis; secretion functions of Jurkat T cell were detected by ELISA assay; effects of exosomes on apoptosis of Jurkat T cell were detected by soluble Fas block experiment; effects on the protein expression of FasL, caspase, Bax and Bcl-2 were assessed by Western blot analysis. Results Exosomes could inhibit Jurkat T cell proliferation, 10 μg/mL exosomes act on Jurkat T cell for 24 and 72 h, growth inhibition rate was (19. 64 ±0. 92)% and (36. 24 ± 1. 12)% ; while 400 μg/mL exosomes act on it for 24 h and 72 h, growth inhibition rate was (55.96 ± 1.35)% and (76.51 ± 1. 37)% respectively. Exosomes could induce Jurkat T cell apoptosis, 10 μg/mL exosomes act on Jurkat T cell for 8 h, apoptosis rate was (7. 31 ±1.32)% , extending this monitoring to 24 h, apoptosis rate was (20. 19 ± 1.47)% ; while 400μg/mL exosomes act on it for 8 and 24 h, apoptosis rate was (27. 28 ± 1. 29)% and (41.72 ±0.88)% respectively. Exosomes also suppressed IL-2, IFN-γ, IL-6 and IL-10 secretion obviously. FasL was highly expressed in exosomes, soluble Fas block could reverse Jurkat T cell apoptosis. In this course, caspase-3 , caspase-8, caspase-9 were activated, and the ratio of Bax/Bcl-2 increased. Conclusion Exosomes could inhibit the growth of Jurkat T cell and induce apoptosis. It could mediate tumor immune escape.%目的 体外研究肾癌786-0细胞来源的exosomes介导肿瘤免疫逃逸的机制.方法 采用CCK-8法检测肾癌786-0细胞来源的exosomes对Jurkat T细胞生长的影响,瑞氏-姬姆萨染色检测Jurkat T细胞形态变化,Annexin V-FITC/PI双染色流式细胞术检测Jurkat T

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

    Energy Technology Data Exchange (ETDEWEB)

    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.

  8. Immune activation induces immortalization of HTLV-1 LTR-Tax transgenic CD4+ T cells.

    Science.gov (United States)

    Swaims, Alison Y; Khani, Francesca; Zhang, Yingyu; Roberts, Arthur I; Devadas, Satish; Shi, Yufang; Rabson, Arnold B

    2010-10-21

    Infection with the human T-cell leukemia virus-1 (HTLV-1) results in a variety of diseases including adult T-cell leukemia/lymphoma (ATL). Although the pathogenesis of these disorders is poorly understood, it involves complex interactions with the host immune system. Activation of infected T cells may play an important role in disease pathogenesis through induction of the oncogenic HTLV-1 Tax transactivator protein. To test this hypothesis, we employed transgenic mice in which Tax is regulated by the HTLV-1 LTR. T-cell receptor stimulation of LTR-Tax CD4(+) T cells induced Tax expression, hyper-proliferation, and immortalization in culture. The transition to cellular immortalization was accompanied by markedly increased expression of the antiapoptotic gene, mcl-1, previously implicated as important in T-cell survival. Immortalized cells exhibited a CD4(+)CD25(+)CD3(-) phenotype commonly observed in ATL. Engraftment of activated LTR-Tax CD4(+) T cells into NOD/Shi-scid/IL-2Rγ null mice resulted in a leukemia-like phenotype with expansion and tissue infiltration of Tax(+), CD4(+) lymphocytes. We suggest that immune activation of infected CD4(+) T cells plays an important role in the induction of Tax expression, T-cell proliferation, and pathogenesis of ATL in HTLV-1-infected individuals. PMID:20634377

  9. CXCL9 Is Important for Recruiting Immune T Cells into the Brain and Inducing an accumulation of the T Cells to the areas of tachyzoite proliferation to prevent reactivation of chronic cerebral infection with Toxoplasma gondii

    Science.gov (United States)

    T cells are required to maintain the latency of chronic infection with Toxoplasma gondii in the brain. In the present study, we examined the role of non-ELR (glutamic acid-leucine-arginine) CXC chemokine CXCL9 for T cell recruitment to prevent reactivation of infection with T. gondii. SCID mice were...

  10. Quantification of uncoupling protein 2 reveals its main expression in immune cells and selective up-regulation during T-cell proliferation.

    Directory of Open Access Journals (Sweden)

    Anne Rupprecht

    Full Text Available Uncoupling protein 2 (UCP2 is an inner mitochondrial membrane protein. Although the protein was discovered in 1997, its function and even its tissue distribution are still under debate. Here we present a quantitative analysis of mRNA and protein expression in various mice tissues, revealing that UCP2 is mainly expressed in organs and cells associated with the immune system. Although the UCP2 gene is present in the brain, as demonstrated using quantitative RT-PCR, the protein was not detectable in neurons under physiological conditions. Instead, we could detect UCP2 in microglia, which act in the immune defense of the central nervous system. In lymphocytes, activation led to a ten-fold increase of UCP2 protein expression simultaneously to the increase in levels of other mitochondrial proteins, whereas lymphocyte re-stimulation resulted in the selective increase of UCP2. The highest detected level of UCP2 expression in stimulated T-cells (0.54 ng/(µg total cellular protein was approximately 200 times lower than the level of UCP1 in brown adipose tissue from room temperature acclimated mice. Both the UCP2 expression pattern and the time course of up-regulation in stimulated T-cells imply UCP2's involvement in the immune response, probably by controlling the metabolism during cell proliferation.

  11. RNA-seq Analysis of δ9-Tetrahydrocannabinol-treated T Cells Reveals Altered Gene Expression Profiles That Regulate Immune Response and Cell Proliferation.

    Science.gov (United States)

    Yang, Xiaoming; Bam, Marpe; Nagarkatti, Prakash S; Nagarkatti, Mitzi

    2016-07-22

    Marijuana has drawn significant public attention and concern both for its medicinal and recreational use. Δ9-Tetrahydrocannabinol (THC), which is the main bioactive component in marijuana, has also been shown to possess potent anti-inflammatory properties by virtue of its ability to activate cannabinoid receptor-2 (CB-2) expressed on immune cells. In this study, we used RNA-seq to quantify the transcriptomes and transcript variants that are differentially regulated by THC in super antigen-activated lymph node cells and CD4(+) T cells. We found that the expressions of many transcripts were altered by THC in both total lymph node cells and CD4(+) T cells. Furthermore, the abundance of many miRNA precursors and long non-coding RNAs was dramatically altered in THC-treated mice. For example, the expression of miR-17/92 cluster and miR-374b/421 cluster was down-regulated by THC. On the other hand miR-146a, which has been shown to induce apoptosis, was up-regulated by THC. Long non-coding RNAs that are expressed from the opposite strand of CD27 and Appbp2 were induced by THC. In addition, THC treatment also caused alternative promoter usage and splicing. The functions of those altered transcripts were mainly related to immune response and cell proliferation. PMID:27268054

  12. Development of ADA Against Recombinant Human Interferon Beta in Immune Tolerant Mice Requires Rapid Recruitment of CD4(+) T Cells, Induces Formation of Germinal Centers but Lacks Susceptibility for (Most) Adjuvants

    NARCIS (Netherlands)

    Kijanka, Grzegorz; Sauerborn, Melody; Boon, Louis; Schellekens, Huub; Brinks, Vera

    2015-01-01

    Immunological processes leading to formation of antidrug antibodies (Abs) against recombinant human proteins remain poorly understood. Animal and clinical studies revealed that immunogenicity shares both T-cell-dependent (requirement of CD4(+) T cells, isotype switching) and T-cell-independent (invo

  13. Autoantibodies in autoimmune thyroid disease promote immune complex formation with self antigens and increase B cell and CD4+ T cell proliferation in response to self antigens

    DEFF Research Database (Denmark)

    Nielsen, Claus Henrik; Hegedüs, Laszlo; Leslie, Robert Graham Quinton

    2004-01-01

    B cells are centrally involved as antigen-presenting cells in certain autoimmune diseases. To establish whether autoantibodies form immune complexes (IC) with self-antigens in autoimmune thyroid disease (AITD) and promote B cell uptake of self-antigen, sera from patients with Hashimoto......'s thyroiditis (HT), Graves' disease (GD) and healthy controls were incubated with human thyroglobulin (Tg) before adding normal peripheral blood mononuclear cells. The deposition of immunoglobulins and C3 fragments on B cells was then assessed. Inclusion of Tg in serum from HT patients promoted B cell capture...... of IgG and C3 fragments. Furthermore, the binding of Tg to B cells in preparations of normal blood cells was higher in HT serum than in serum from controls and correlated positively with the serum anti-Tg activity, as did the B and CD4+ T cell proliferation. Disruption of the three-dimensional structure...

  14. Alternative splicing isoform of T cell factor 4K suppresses the proliferation and metastasis of non-small cell lung cancer cells.

    Science.gov (United States)

    Fan, Y C; Min, L; Chen, H; Liu, Y L

    2015-10-30

    The Wnt pathway has been implicated in the initiation, progression, and metastasis of lung cancer. T cell factor 4, a member of TCF/LEF family, acts as a transcriptional factor for Wnt pathways in lung cancer. Increasing amounts of evidence have shown that TCF-4 has multiple alternative splicing isoforms with transactivation or transrepression activity toward the Wnt pathway. Here, we found the presence of multiple TCF-4 isoforms in lung cancer cell lines and in normal bronchial epithelial cells. TCF-4K isoform expression was significantly decreased in lung cancer cells compared with normal bronchial epithelial cells and was identified as a transcriptional suppressor of the Wnt pathway in non-small cell lung carcinoma (NSCLC). Overexpression of TCF-4K significantly inhibited the proliferation and migration of NSCLC cells. Collectively, our data indicate that TCF-4K functions as a tumor suppressor in NSCLC by down-regulating the Wnt pathway.

  15. The in vitro effect of oxidized LDL and PHA on proliferation and gene expression of regulatory T cells in patients with atherosclerosis.

    Directory of Open Access Journals (Sweden)

    Azadeh Mottaghi

    2012-09-01

    Full Text Available Atherosclerosis is a chronic inflammatory condition that affects the arterial wall. Oxidized low- density lipoprotein (ox-LDL seems to have an important role in atherosclerotic plaque formation.This study was performed to investigate the effects of ox-LDL as well as PHA on proliferation and gene expression of  peripheral blood  mononuclear  cells (PBMCs in patients with atherosclerosis compared  to  healthy controls. Proliferation of  PBMCs was assessed by BrdU assay, while gene expression was assessed by real-time PCR.Both PHA and ox-LDL significantly induced proliferation of PBMCs of patients and controls. PBMCs  from  controls  showed  significantly higher  proliferation  when  stimulated  with  ox-LDL compared to patients. Expression of TGF-β was significantly lower in PBMCs from patients compared to healthy controls (p<0.001. Following simulation with PHA, TGF-β and Foxp3 gene expression levels in patients and controls were significantly decreased (p<0.001. Expression of Foxp3 in PBMCs treated with ox-LDL was significantly decreased in patients and controls.Decreased expression of TGF-β and Foxp3 genes after ox-LDL stimulation may be due to more sensitivity of Treg cells than effector T cells to ox-LDL. Presence of ox-LDL within atheroma could be associated with the diminished population of Treg cells in the atherosclerotic patients.

  16. Induction of IL-10- and IFN-gamma-producing T-cell responses by autoreactive T-cells expressing human T-cell leukemia virus type I Tax.

    Science.gov (United States)

    Takatsuka, Natsuko; Hasegawa, Atsuhiko; Takamori, Ayako; Shimizu, Yukiko; Kato, Hirotomo; Ohashi, Takashi; Amagasa, Teruo; Masuda, Takao; Kannagi, Mari

    2009-09-01

    Human T-cell leukemia virus type I (HTLV-I) is associated with adult T-cell leukemia, HTLV-I-associated myelopathy/tropical spastic paraparesis and various autoimmune-like disorders. T-cell immune suppression is also associated with HTLV-I infection. Mechanisms of diverse immune dysregulation in HTLV-I infection are obscure. Here, we investigated a potential link between autoimmunity and immune suppression in HTLV-I infection. G14, an IL-2-dependent HTLV-I-negative CD4(+)CD8(+) T-cell line previously established from an HTLV-I-infected rat, constantly proliferated and produced IFN-gamma. IFN-gamma production by G14 cells was dependent on interactions between CD4 and MHC-II, suggesting that G14 cells recognized self-antigens presented by MHC-II on themselves. To examine immune response to G14 cells, we inoculated G14 cells into syngeneic naive rats. Interestingly, T-cells isolated from these rats vigorously proliferated when stimulated with G14-Tax cells that stably expressed HTLV-I Tax, but not with G14 cells. G14-Tax-mediated T-cell proliferation was abrogated by antibodies to CD80 and CD86 that were up-regulated in G14-Tax cells. T-cells propagated by repetitive G14-Tax cell stimulations in culture with IL-2 expressed CD4, CD25 and cytolytic T lymphocyte-associated antigen 4 (CTLA-4), produced abundant amounts of IL-10 and IFN-gamma in response to G14 cells and suppressed growth of G14 cells mainly through supernatant-mediated mechanisms. Similar IL-10- and IFN-gamma-producing CD4(+)CD25(+)CTLA-4(+) T-cells were predominantly induced in culture of splenocytes from HTLV-I-infected rats following stimulation with G14-Tax cells. These results implied that expression of Tax in the otherwise low immunogenic autoreactive T-cells induced IL-10- and IFN-gamma-producing T-cell responses with regulatory effects against the autoreactive cells. Our findings provide new insights into the complex immune conditions underlying HTLV-I-associated diseases. PMID:19654198

  17. 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.

  18. Accumulation of immunoglobulin-containing cells in the gut mucosa and presence of faecal immunoglobulin in severe combined immunodeficient (scid) mice with T cell-induced inflammatory bowel disease (IBD)

    DEFF Research Database (Denmark)

    Bregenholt, S; Brimnes, J; Reimann, J;

    1998-01-01

    Scid mice transplanted either with a gut wall graft or with low numbers of purified CD4+ T cells from immunocompetent syngeneic donor mice show clinical signs of IBD 3-4 months post-transplantation. The disease is mediated by mucosa-infiltrating CD4+ TCR alphabeta+ T cells. The pathology of 52...

  19. Role of glucagon-like peptide-1 analogue liraglutide played in the proliferation of CD4~+ CD25~- T cells in normal people and type 1 diabetic patients in vitro

    Institute of Scientific and Technical Information of China (English)

    胡瑛

    2013-01-01

    Objective To study the role of glucagon-like peptide-1 (GLP-1) analogue liraglutide played in the proliferation of CD4+CD25-T cells in normal people and newly-onset type 1 diabetic patients,and to evaluate the possible immune regulatory role of liraglutide in the

  20. Blockade of the PD-1/PD-L1 axis augments lysis of AML cells by the CD33/CD3 BiTE antibody construct AMG 330: reversing a T-cell-induced immune escape mechanism.

    Science.gov (United States)

    Krupka, C; Kufer, P; Kischel, R; Zugmaier, G; Lichtenegger, F S; Köhnke, T; Vick, B; Jeremias, I; Metzeler, K H; Altmann, T; Schneider, S; Fiegl, M; Spiekermann, K; Bauerle, P A; Hiddemann, W; Riethmüller, G; Subklewe, M

    2016-02-01

    Bispecific T-cell engagers (BiTEs) are very effective in recruiting and activating T cells. We tested the cytotoxicity of the CD33/CD3 BiTE antibody construct AMG 330 on primary acute myeloid leukemia (AML) cells ex vivo and characterized parameters contributing to antileukemic cytolytic activity. The E:T ratio and the CD33 expression level significantly influenced lysis kinetics in long-term cultures of primary AML cells (n=38). AMG 330 induced T-cell-mediated proinflammatory conditions, favoring the upregulation of immune checkpoints on target and effector cells. Although not constitutively expressed at the time of primary diagnosis (n=123), PD-L1 was strongly upregulated on primary AML cells upon AMG 330 addition to ex vivo cultures (n=27, Pcheckpoint molecules in upcoming clinical trials with AMG 330 to enhance BiTE antibody construct-mediated cytotoxicity. PMID:26239198

  1. PD-1/PD-Ls pathways between CD4(+) T cells and pleural mesothelial cells in human tuberculous pleurisy.

    Science.gov (United States)

    Yin, Wen; Tong, Zhao-Hui; Cui, Ai; Zhang, Jian-Chu; Ye, Zhi-Jian; Yuan, Ming-Li; Zhou, Qiong; Shi, Huan-Zhong

    2014-03-01

    Programmed death 1 (PD-1), PD-ligand 1 (PD-L1), and PD-L2 have been demonstrated to be involved in tuberculosis immunity, however, the expression and regulation of PD-1/PD-Ls pathways in pleural mesothelial cells (PMCs) and CD4(+) T cells in tuberculous pleural effusion (TPE) have not been investigated. Expression of PD-1 on CD4(+) T cells and expressions of PD-L1 and PD-L2 on PMCs in TPE were determined. The impacts of PD-1/PD-Ls pathways on proliferation, apoptosis, adhesion, and migration of CD4(+) T cells were explored. Concentrations of soluble PD-l, but not of soluble PD-Ls, were much higher in TPE than in serum. Expressions of PD-1 on CD4(+) T cells in TPE were significantly higher than those in blood. Expressions of PD-Ls were much higher on PMCs from TPE when compared with those from transudative effusion. Interferon-γ not only upregulated the expression of PD-1 on CD4(+) T cells, but also upregulated the expressions of PD-Ls on PMCs. Blockage PD-1/PD-Ls pathways abolished the inhibitory effects on proliferation and adhesion activity of CD4(+) T cells induced by PMCs. PD-1/PD-Ls pathways on PMCs inhibited proliferation and adhesion activity of CD4(+) T cells, suggesting that Mycobacterium tuberculosis might exploit PD-1/PD-Ls pathways to evade host cell immune response in human.

  2. HIV-1 Tat protein induces the production of IDO in human monocyte derived-dendritic cells through a direct mechanism: effect on T cells proliferation.

    Directory of Open Access Journals (Sweden)

    Rémi Planès

    Full Text Available During HIV-1 infection, an increase of indoleamine 2,3 dioxygenase (IDO expression, and dendritic cells (DC dysfunction were often associated with AIDS disease progression. In this work, we investigated the effect of HIV-1 Tat protein on the expression of IDO, in MoDCs. We show that Tat induces IDO protein expression and activity in a dose dependent manner by acting at the cell membrane. Using Tat-mutants, we show that the N-Terminal domain, Tat 1-45, but not the central region, Tat 30-72, is sufficient to induce the expression of active IDO. Tat protein is also able to induce several cytokines in MoDCs, including IFN-γ, a strong inducer of IDO. In order to understand whether IDO is induced directly by Tat protein or indirectly following IFN-γ production, complementary experiments were performed and showed that: i at the kinetic level, Tat induced IDO expression before the production of IFN-γ ii treatment of MoDCs with Tat-conditioned medium was unable to stimulate IDO expression, iii coculture of MoDCs in a transwell cell system did not allow IDO expression in MoDCs not previously treated by Tat, iv direct contact between Tat-treated and untreated MoDCs was not sufficient to induce IDO expression in a Tat-independent manner, and v treatment of MoDCs in the presence of IFN-γ pathway inhibitors, Jak I and Ly294002, inhibited IFN-γ-induced IDO but had no effect on Tat-induced IDO. At the functional level, our data showed that treatment of MoDCs with Tat led to the inhibition of their capacity to stimulate T cell proliferation. This impairement was totally abolished when the stimulation was performed in the presence of 1MT, an inhibitor of IDO activity, arguing for the implication of the kynurenine pathway. By inducing IDO, Tat protein may be considered, as a viral pathogenic factor, in the dysregulation of the DC functions during HIV-1 infection.

  3. Notch信号调节外周T细胞的活化、增殖与分化%Notch signaling regulates activation, proliferation and differentiation of peripheral T cells

    Institute of Scientific and Technical Information of China (English)

    唐晓燕; 季晓辉

    2008-01-01

    The differentiation of naive T cells to effector/memory T cells is regulated by a variety of factors. The recent advance of the contribution of Notch signaling in this differentiation step has provided a new path for better understanding the acquisition or persistence of the effector function of mature T cells. A growing body of literature indicates that the Notch pathway can influence the development of T cells in central immune organs. It is now clear that Notch' s ability to regulate cell-fate choices extends into the peripheral immune system, where the activation of the Notch signaling pathway can profoundly alter cytokine production in both CD4+ and CD8+T cells. In this review, we summarized the emerging and, in some points, conflicting evi-dences for Notch signaling on mature T cell activation, proliferation and differentiation. Although the effect of Notch ligation on CD4 + T cell cytokine production varies significantly from one report to another, it is clear that the Notch pathway is an important regulator of T cell activity. Specifically, the available data demonstrated that APCs utilize the Notch pathway to instruct T cell differentiation programs.%初始T细胞分化为效应T和记忆T细胞受到多种因素调节.最近在Notch信号途径的研究进展显示它也参于T细胞的活化与分化.大量研究已经表明Notch信号途径可以影响T细胞在中枢免疫器官的发育,现在关于它调节外周T细胞的分化状态也积累不少证据,Notch信号活化之后能够改变CD4+和CD8+T细胞分泌细胞因子的特点.以下着重介绍Notch信号参于调节外周T细胞的活化、增殖和分化的最新资料,尽管不同的研究者所得实验结果有冲突之处,但已经提示Notch信号在T细胞外周发育中的重要意义,特别重要的是抗原递呈细胞(APC)可以通过Notch信号途径调节T细胞的分化.

  4. PRRSV-infected monocyte-derived dendritic cells express high levels of SLA-DR and CD80/86 but do not stimulate PRRSV-naïve regulatory T cells to proliferate.

    Science.gov (United States)

    Rodríguez-Gómez, Irene M; Käser, Tobias; Gómez-Laguna, Jaime; Lamp, Benjamin; Sinn, Leonie; Rümenapf, Till; Carrasco, Librado; Saalmüller, Armin; Gerner, Wilhelm

    2015-05-20

    In vitro generated monocyte-derived dendritic cells (moDCs) have frequently been used to study the influence of porcine reproductive and respiratory syndrome virus (PRRSV) infection on antigen presenting cells. However, obtained results have often been conflicting in regard to expression of co-stimulatory molecules and interaction with T cells. In this study we performed a detailed phenotypic characterisation of PRRSV-infected moDCs and non-infected moDCs. For CD163 and CD169, which are involved in PRRSV-entry into host cells, our results show that prior to infection porcine moDCs express high levels of CD163 but only very low levels for CD169. Following infection with either PRRSV-1 or PRRSV-2 strains after 24 h, PRRSV-nucleoprotein (N-protein)(+) and N-protein(-) moDCs derived from the same microculture were analyzed for expression of swine leukocyte antigen-DR (SLA-DR) and CD80/86. N-protein(+) moDCs consistently expressed higher levels of SLA-DR and CD80/86 compared to N-protein(-) moDCs. We also investigated the influence of PRRSV-infected moDCs on proliferation and frequency of Foxp3(+) regulatory T cells present within CD4(+) T cells in in vitro co-cultures. Neither CD3-stimulated nor unstimulated CD4(+) T cells showed differences in regard to proliferation and frequency of Foxp3(+) T cells following co-cultivation with either PRRSV-1 or PRRSV-2 infected moDCs. Our results suggest that a more detailed characterisation of PRRSV-infected moDCs will lead to more consistent results across different laboratories and PRRSV strains as indicated by the major differences in SLA-DR and CD80/86 expression between PRRSV-infected and non-infected moDCs present in the same microculture.

  5. PRRSV-infected monocyte-derived dendritic cells express high levels of SLA-DR and CD80/86 but do not stimulate PRRSV-naïve regulatory T cells to proliferate.

    Science.gov (United States)

    Rodríguez-Gómez, Irene M; Käser, Tobias; Gómez-Laguna, Jaime; Lamp, Benjamin; Sinn, Leonie; Rümenapf, Till; Carrasco, Librado; Saalmüller, Armin; Gerner, Wilhelm

    2015-01-01

    In vitro generated monocyte-derived dendritic cells (moDCs) have frequently been used to study the influence of porcine reproductive and respiratory syndrome virus (PRRSV) infection on antigen presenting cells. However, obtained results have often been conflicting in regard to expression of co-stimulatory molecules and interaction with T cells. In this study we performed a detailed phenotypic characterisation of PRRSV-infected moDCs and non-infected moDCs. For CD163 and CD169, which are involved in PRRSV-entry into host cells, our results show that prior to infection porcine moDCs express high levels of CD163 but only very low levels for CD169. Following infection with either PRRSV-1 or PRRSV-2 strains after 24 h, PRRSV-nucleoprotein (N-protein)(+) and N-protein(-) moDCs derived from the same microculture were analyzed for expression of swine leukocyte antigen-DR (SLA-DR) and CD80/86. N-protein(+) moDCs consistently expressed higher levels of SLA-DR and CD80/86 compared to N-protein(-) moDCs. We also investigated the influence of PRRSV-infected moDCs on proliferation and frequency of Foxp3(+) regulatory T cells present within CD4(+) T cells in in vitro co-cultures. Neither CD3-stimulated nor unstimulated CD4(+) T cells showed differences in regard to proliferation and frequency of Foxp3(+) T cells following co-cultivation with either PRRSV-1 or PRRSV-2 infected moDCs. Our results suggest that a more detailed characterisation of PRRSV-infected moDCs will lead to more consistent results across different laboratories and PRRSV strains as indicated by the major differences in SLA-DR and CD80/86 expression between PRRSV-infected and non-infected moDCs present in the same microculture. PMID:25990845

  6. Uptake of donor lymphocytes treated with 8-methoxypsoralen and ultraviolet A light by recipient dendritic cells induces CD4+CD25+Foxp3+ regulatory T cells and down-regulates cardiac allograft rejection

    International Nuclear Information System (INIS)

    Extracorporeal photopheresis (ECP) is an effective immunomodulatory therapy and has been demonstrated to be beneficial for graft-vs-host disease and solid-organ allograft rejection. ECP involves reinfusion of a patient's autologous peripheral blood leukocytes treated ex vivo with 8-methoxypsoralen and UVA light radiation (PUVA). Previous studies focused only on ECP treatment of recipient immune cells. Our study is the first to extend the target of ECP treatment to donor immune cells. The results of in vitro co-culture experiments demonstrate uptake of donor PUVA-treated splenic lymphocytes (PUVA-SPs) by recipient immature dendritic cells (DCs). Phagocytosis of donor PUVA-SPs does not stimulate phenotype maturation of recipient DCs. In the same co-culture system, donor PUVA-SPs enhanced production of interleukin-10 and interferon-γ by recipient DCs and impaired the subsequent capability of recipient DCs to stimulate recipient naive T cells. Phagocytosis of donor PUVA-SP (PUVA-SP DCs) by recipient DCs shifted T-cell responses in favor of T helper 2 cells. Infusion of PUVA-SP DCs inhibited cardiac allograft rejection in an antigen-specific manner and induced CD4+CD25highFoxp3+ regulatory T cells. In conclusion, PUVA-SP DCs simultaneously deliver the donor antigen and the regulatory signal to the transplant recipient, and thus can be used to develop a novel DC vaccine for negative immune regulation and immune tolerance induction.

  7. Uptake of donor lymphocytes treated with 8-methoxypsoralen and ultraviolet A light by recipient dendritic cells induces CD4{sup +}CD25{sup +}Foxp3{sup +} regulatory T cells and down-regulates cardiac allograft rejection

    Energy Technology Data Exchange (ETDEWEB)

    Zheng, De-Hua [Organ Transplant Center, Chinese PLA 309th Hospital, No. 17A Hei-Shan-Hu Road, Beijing 100091 (China); Dou, Li-Ping [Department of Hematology, Chinese PLA General Hospital, No. 28 Fu-Xing Road, Beijing 100853 (China); Wei, Yu-Xiang; Du, Guo-Sheng; Zou, Yi-Ping; Song, Ji-Yong; Zhu, Zhi-Dong; Cai, Ming; Qian, Ye-Yong [Organ Transplant Center, Chinese PLA 309th Hospital, No. 17A Hei-Shan-Hu Road, Beijing 100091 (China); Shi, Bing-Yi, E-mail: shibingyi@medmail.com.cn [Organ Transplant Center, Chinese PLA 309th Hospital, No. 17A Hei-Shan-Hu Road, Beijing 100091 (China)

    2010-05-14

    Extracorporeal photopheresis (ECP) is an effective immunomodulatory therapy and has been demonstrated to be beneficial for graft-vs-host disease and solid-organ allograft rejection. ECP involves reinfusion of a patient's autologous peripheral blood leukocytes treated ex vivo with 8-methoxypsoralen and UVA light radiation (PUVA). Previous studies focused only on ECP treatment of recipient immune cells. Our study is the first to extend the target of ECP treatment to donor immune cells. The results of in vitro co-culture experiments demonstrate uptake of donor PUVA-treated splenic lymphocytes (PUVA-SPs) by recipient immature dendritic cells (DCs). Phagocytosis of donor PUVA-SPs does not stimulate phenotype maturation of recipient DCs. In the same co-culture system, donor PUVA-SPs enhanced production of interleukin-10 and interferon-{gamma} by recipient DCs and impaired the subsequent capability of recipient DCs to stimulate recipient naive T cells. Phagocytosis of donor PUVA-SP (PUVA-SP DCs) by recipient DCs shifted T-cell responses in favor of T helper 2 cells. Infusion of PUVA-SP DCs inhibited cardiac allograft rejection in an antigen-specific manner and induced CD4{sup +}CD25{sup high}Foxp3{sup +} regulatory T cells. In conclusion, PUVA-SP DCs simultaneously deliver the donor antigen and the regulatory signal to the transplant recipient, and thus can be used to develop a novel DC vaccine for negative immune regulation and immune tolerance induction.

  8. Possible mechanism for the regulation of glucose on proliferation, inhibition and apoptosis of colon cancer cells induced by sodium butyrate

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    AIM: To study the effect of glucose on sodium butyrateinduced proliferation inhibition and apoptosis in HT-29 cell line, and explored its possible mechanisms.METHODS: HT-29 cells were grown in RPMI-1640 medium supplemented with 10% fetal calf serum, and were allowed to adhere for 24 h, and then replaced with experimental medium. Cell survival rates were detected by MTT assay. Apoptosis was detected by TUNEL assay. Glucose transport protein 1 (GLUT1) and monocarboxylate transporter 1 (MCT1) mRNA expression was detected by RT-PCR.RESULTS: Low concentration of glucose induced apoptosis and regulated proliferation in HT-29 cell line, and glucose can obviously inhibit the effect of proliferation inhibition and apoptosis induced by sodium butyrate. Glucose also down-regulated the expression of MCT1mRNA (0.28 ± 0.07 vs 0.19 ± 0.10, P < 0.05), and decreased the expression of GLUT1mRNA slightly (0.18 ± 0.04 vs 0.13 ± 0.03, P < 0.05).CONCLUSION: Glucose can regulate the effect of proliferation inhibition and apoptosis induced by sodium butyrate and this influence may be associated with the intracellular concentration of glucose and sodium butyrate.

  9. [Src kinase-MAPK signal pathway plays a role in proliferation of endothelial cells induced by o-HA].

    Science.gov (United States)

    Yang, Cui Xia; Liu, Yi Wen; He, Yi Qing; Gao, Feng

    2006-12-01

    To investigate the effect of hyaluronan oligosaccharides (o-HA) on endothelial cell (EC) proliferation and the possible mechanism involved. The cell proliferation was determined by cell counting and flow cytometer, and the phosphorylation of Src kinase and ERK-1/2 as well as the expression of cyclin D1 were assayed by western blot. o-HA at concentration of 10 microg/ml caused a significantly increase in both cell cycle and cell number of EC. With increasing time and amount of o-HA of exposure, there was no further increase in the growth of cells. The cell proliferation started to be significant at 12 hr and reached peak at 72 hr. At the same time,the phosphorylation of Src kinase and ERK-1/2 was enhanced after treated with l microg/ml of o-HA at 5 min and the expression of cyclin D1 was enhanced by treating PIEC cells with o-HA at 3 hr. o-HA may increase EC growth by stimulating the Src kinase and MAPK signal pathway and thus promote the proliferation of PIEC cells,in which the regulation of cyclin D1 expression may be involved. PMID:17348201

  10. Effects and underlying mechanisms of curcumin on the proliferation of vascular smooth muscle cells induced by Chol:MβCD

    International Nuclear Information System (INIS)

    Proliferation of vascular smooth muscle cells (VSMCs) contributes to the development of various cardiovascular diseases. Curcumin, extracted from Curcumae longae, has been shown a variety of beneficial effects on human health, including anti-atherosclerosis by mechanisms poorly understood. In the present study, we attempted to investigate whether curcumin has any effect on VSMCs proliferation and the potential mechanisms involved. Our data showed curcumin concentration-dependently abrogated the proliferation of primary rat VSMCs induced by Chol:MβCD. To explore the underlying cellular and molecular mechanisms, we found that curcumin was capable of restoring caveolin-1 expression which was reduced by Chol:MβCD treatment. Moreover, curcumin abrogated the increment of phospho-ERK1/2 and nuclear accumulation of ERK1/2 in primary rat VSMCs induced by Chol:MβCD, which led to a suppression of AP-1 promoter activity stimulated by Chol:MβCD. In addition, curcumin was able to reverse cell cycle progression induced by Chol:MβCD, which was further supported by its down-regulation of cyclinD1 and E2F promoter activities in the presence of Chol:MβCD. Taking together, our data suggest curcumin inhibits Chol:MβCD-induced VSMCs proliferation via restoring caveolin-1 expression that leads to the suppression of over-activated ERK signaling and causes cell cycle arrest at G1/S phase. These novel findings support the beneficial potential of curcumin in cardiovascular disease.

  11. Effect of zinc supplementation on serum zinc concentration and T cell proliferation in nursing home elderly:A randomized double-blind placebo-controlled trial

    Science.gov (United States)

    Background: Zinc is essential for the regulation of immune response. T cell function declines with age. Zinc supplementation has the potential to improve serum zinc concentrations and immunity of nursing home elderly with low serum zinc concentration. Objective: We aimed to determine the effect of ...

  12. N-Octanoyl dopamine transiently inhibits T cell proliferation via G1 cell-cycle arrest and inhibition of redox-dependent transcription factors

    NARCIS (Netherlands)

    Wedel, Johannes; Hottenrott, Maximillia C.; Stamellou, Eleni; Breedijk, Annette; Tsagogiorgas, Charalambos; Hillebrands, Jan-Luuk; Yard, Benito A.

    2014-01-01

    Recently, we developed a nonhemodynamic dopamine derivative, NOD, which has profound anti-inflammatory effects in vitro. As NOD also protects rats from ischemic AKI, the present study tested whether NOD is able to modulate cellular immunity for potential use as a T cell-suppressive agent. To this en

  13. A subset of dendritic cells induces CD4+ T cells to produce IFN-γ by an IL-12–independent but CD70-dependent mechanism in vivo

    OpenAIRE

    Soares, Helena; Waechter, HaeNa; Glaichenhaus, Nicholas; Mougneau, Evelyne; Yagita, Hideo; Mizenina, Olga; Dudziak, Diana; Nussenzweig, Michel C.; Steinman, Ralph M.

    2007-01-01

    Interferon (IFN)-γ, a cytokine critical for resistance to infection and tumors, is produced by CD4+ helper T lymphocytes after stimulation by cultured dendritic cells (DCs) that secrete a cofactor, interleukin (IL)-12. We have identified a major IL-12–independent pathway whereby DCs induce IFN-γ–secreting T helper (Th)1 CD4+ T cells in vivo. This pathway requires the membrane-associated tumor necrosis family member CD70 and was identified by targeting the LACK antigen from Leishmania major wi...

  14. Leptin Inhibits the Proliferation of Vascular Smooth Muscle Cells Induced by Angiotensin II through Nitric Oxide-Dependent Mechanisms

    Directory of Open Access Journals (Sweden)

    Amaia Rodríguez

    2010-01-01

    Full Text Available Objective. This study was designed to investigate whether leptin modifies angiotensin (Ang II-induced proliferation of aortic vascular smooth muscle cells (VSMCs from 10-week-old male Wistar and spontaneously hypertensive rats (SHR, and the possible role of nitric oxide (NO. Methods. NO and NO synthase (NOS activity were assessed by the Griess and 3H-arginine/citrulline conversion assays, respectively. Inducible NOS (iNOS and NADPH oxidase subutnit Nox2 expression was determined by Western-blot. The proliferative responses to Ang II were evaluated through enzymatic methods. Results. Leptin inhibited the Ang II-induced proliferative response of VSMCs from control rats. This inhibitory effect of leptin was abolished by NOS inhibitor, NMMA, and iNOS selective inhibitor, L-NIL, and was not observed in leptin receptor-deficient fa/fa rats. SHR showed increased serum leptin concentrations and lipid peroxidation. Despite a similar leptin-induced iNOS up-regulation, VSMCs from SHR showed an impaired NOS activity and NO production induced by leptin, and an increased basal Nox2 expression. The inhibitory effect of leptin on Ang II-induced VSMC proliferation was attenuated. Conclusion. Leptin blocks the proliferative response to Ang II through NO-dependent mechanisms. The attenuation of this inhibitory effect of leptin in spontaneous hypertension appears to be due to a reduced NO bioavailability in VSMCs.

  15. Lung effector memory and activated CD4+ T cells display enhanced proliferation in SP-A-deficient mice during allergen-mediated inflammation

    OpenAIRE

    Pastva, Amy M.; Mukherjee, Sambuddho; Giamberardino, Charles; Hsia, Bethany; Lo, Bernice; Sempowski, Gregory D; Wright, Jo Rae

    2011-01-01

    Although many studies show that pulmonary Surfactant Protein A (SP-A) functions in innate immunity, fewer studies have addressed its role in adaptive immunity and allergic hypersensitivity. We hypothesized that SP-A modulates the phenotype and prevalence of dendritic cells (DCs) and CD4+ T cells to inhibit Th2-associated inflammatory indices associated with allergen-induced inflammation. In an ovalbumin (OVA) model of allergic hypersensitivity, SP-A deficient (SP-A−/−) mice had greater eosino...

  16. 肥大细胞体外诱生CD4~+CD25~+Foxp3~+调节性T细胞的作用%Mast cells induce CD4~+CD25~+Foxp3~+ regulatory T cells in vitro

    Institute of Scientific and Technical Information of China (English)

    张维娜; 周巧丹; 雒真龙; 陈忠华; 吴轲; 周鸿敏; 何文涛; 高英; 汪理; 林星光; 方泽民; 蔡兰军

    2009-01-01

    探索小鼠骨髓源性肥大细胞能否在体外诱生CD4~+CD25~+Foxp3~+调节性T细胞.从小鼠股骨获取骨髓细胞,加入完全RPMI 1640培养基(含IL-3和SCF各10 ng/m1)诱导4周.用甲苯胺蓝染色法观察肥大细胞异染颗粒;流式检测CD117和FcεRIα双阳性细胞比例.将肥大细胞与同基因来源的T细胞按不同比例(1,2、1:1、2:1)置于48孔培养板中培养,作为三个实验组;未加肥大细胞的单独T细胞组作对照组.四个组均加入CD3抗体和CD28抗体各2μg/ml,IL-2 1 000U/ml,5 d后流式检测Foxp3表达情况.RT-PCR,免疫组化法检测肥大细胞中TGF-β1的表达.与对照组相比,实验组Foxp3表达均升高(对照组:3.37%±0.40%;实验组为:8.23%±0.80%、10.87%±1.25%、13.63%±0.55%).RT-PCR和免疫组化均检出TGF-β1表达.肥大细胞能在体外诱导T细胞转化为CD4~+CD25~+Foxp3~+调节性T细胞,可能与肥大细胞表达TGF-β1有关.%To detect whether mouse mast cells can induce CD4~+ CD25~+ Foxp3+ regulatory T cells (Treg) in vitro. Bone marrow cells obtained from C57BL/6 (H-2b) mice were cultured with IL-3 (10 ng/ml) and SCF (10 ng/ml) for 4 weeks. The purity of bone marrow mast cells (BMMCs) was tested by flow cytometry. The expression of TGF-β1 in BMMCs was tested by RT-PCR and immunohistochemistry. Then the BMMCs were co-cultured with T cells of C57BL/6 mice at 1 : 2, 1 : 1 and 2 : 1 ratios in the presence of anti-CD3 antibody(2μg/ml), anti-CD28 antibody(2μg/ml) and IL-2 (1 000 U/ml). The percentages of CD4~+ CD25~+ Foxp3+ T cells in the co-cultured system were compared among different groups by flow cytometry on day 5. It was found that the percentages of CD4~+ CD25~+ Foxp3+ cells were significantly higher in the ratio of BMMC/T 2 : 1 group(13.63 ± 0.55%), the 1 : 1 group(10.87% ± 1.25%)and 1 : 2 group(8. 23% ± 0.80%) than in the control group(3.37% ± 0.40%). The expression of TGF-β1 was determined in the mouse BMMCs by RT-PCR and immunohistochemistry. Our find

  17. Expression of orphan G-protein coupled receptor GPR174 in CHO cells induced morphological changes and proliferation delay via increasing intracellular cAMP

    Energy Technology Data Exchange (ETDEWEB)

    Sugita, Kazuya; Yamamura, Chiaki; Tabata, Ken-ichi [Laboratory of Pharmacoinformatics, Graduate School of Ritsumeikan University, Kusatsu, Shiga 525-8577 (Japan); Fujita, Norihisa, E-mail: nori@ph.ritsumei.ac.jp [Laboratory of Pharmacoinformatics, Graduate School of Ritsumeikan University, Kusatsu, Shiga 525-8577 (Japan); School of Pharmacy, Ristumeikan University, Kusatsu, Shiga 525-8577 (Japan)

    2013-01-04

    Highlights: Black-Right-Pointing-Pointer Expression of GPR174 in CHO cells induces morphological changes and proliferation delay. Black-Right-Pointing-Pointer These are due to increase in intracellular cAMP concentration. Black-Right-Pointing-Pointer Lysophosphatidylserine was identified to stimulate GPR174 leading to activate ACase. Black-Right-Pointing-Pointer The potencies of fatty acid moiety on LysoPS were oleoyl Greater-Than-Or-Slanted-Equal-To stearoyl > palmitoyl. Black-Right-Pointing-Pointer We propose that GPR174 is a lysophosphatidylserine receptor. -- Abstract: We established cell lines that stably express orphan GPCR GPR174 using CHO cells, and studied physiological and pharmacological features of the receptor. GPR174-expressing cells showed cell-cell adhesion with localization of actin filaments to cell membrane, and revealed significant delay of cell proliferation. Since the morphological changes of GPR174-cells were very similar to mock CHO cells treated with cholera toxin, we measured the concentration of intracellular cAMP. The results showed the concentration was significantly elevated in GPR174-cells. By measuring intracellular cAMP concentration in GPR174-cells, we screened lipids and nucleotides to identify ligands for GPR174. We found that lysophosphatidylserine (LysoPS) stimulated increase in intracellular cAMP in a dose-dependent manner. Moreover, phosphorylation of Erk was elevated by LysoPS in GPR174 cells. These LysoPS responses were inhibited by NF449, an inhibitor of G{alpha}{sub s} protein. These results suggested that GPR174 was a putative LysoPS receptor conjugating with G{alpha}{sub s}, and its expression induced morphological changes in CHO cells by constitutively activating adenylyl cycles accompanied with cell conjunctions and delay of proliferation.

  18. Human T cell leukemia/lymphoma virus I infection and subsequent cloning of normal human B cells. Direct responsiveness of cloned cells to recombinant interleukin 2 by differentiation in the absence of enhanced proliferation

    OpenAIRE

    1985-01-01

    A human T cell leukemia/lymphoma virus (HTLV)-I-infected B cell clone expressed Tac antigen on its cell surface and responded to recombinant interleukin 2 (IL-2) by increased production of IgM without any increase in proliferation. Anti-Tac antibody completely inhibited the IL-2-induced differentiation of this HTLV-I-infected B cell clone. This study demonstrates that HTLV-I can directly infect normal mature human B cells, and that the Tac antigen, which may be induced by infection with HTLV-...

  19. IKK2dn转染树突状细胞诱导产生的CD4+CD25-T细胞的筛选及鉴定%Screening and function identification of CD4 + CD25 - T cells induced by immature dendritic cells transfected with IKK2dn

    Institute of Scientific and Technical Information of China (English)

    樊彩斌; 张东兴; 温端改; 侯建全; 欧阳骏; 杜科霖

    2012-01-01

    Objective To investigate the method of screening CD4 + CD25 - T cells from regulatory T cells (Treg) induced by recipient-derived immature dendritic cells (imDC) transfected by IKK2dn and loaded with donor antigens,and assess their immunologic function.Methods Rat bone marrow-derived imDC were transfected by IKK2dn and loaded by BN antigen,then cultured with Lewis rats T cells in vitro.From these Treg,CD4 + CD25 T cells were screened by magnetic active cell sorting (MACS),then incubated in secondary mixed lymphocyte reaction ( MLR),with Lewis rat T lymphocytes.Results By MACS,the purity of CD4 + CD25 - T cells was more than 95%.The result of secondary MLR displayed the absorbance value was significantly lower in the CD4 + CD25 - T cells group ( 0.106 ± 0.006 ) than that in BN antigen group (0.189 ± 0.007 ),Adv0-CD4 +T cells group (0.419 ± 0.014) and the third donor group (0.200 ± 0.008) (P <0.05).Conclusion By MACS sereening,we can obtain high purity of CD4 + CD25-T cells from Treg induced by imDC transfected with IKK2dn and loaded by BN rat antigen and recipient Lewis rats T cells.And these T cells can inhibit T cell proliferation with the donor antigen specificity.%目的 探讨从转染IKK2dn并负载供者抗原的未成熟树突状细胞(imDC)诱导产生的调节性T细胞(Treg)中筛选CD4+ CD25 - Treg的方法,并进行鉴定.方法 Lewis大鼠骨髓源性imDC,转染IKK2dn后负载供者BN大鼠抗原,与Lewis大鼠T细胞进行体外混合淋巴细胞反应(MLR)诱导产生Treg,用免疫磁珠法(MACS)筛选出CD4+ CD25 -T细胞,流式细胞仪(FCM)检测细胞纯度.加入CD4+ CD25 -T细胞行再次MLR检测其抑制T细胞增殖的作用.结果 经MACS筛选,CD4+ CD25 -T细胞纯度为(95.78±1.25)%.再次MLR结果显示CD4+ CD25 -T细胞组的吸光度值为(0.106±0.006),低于BN抗原组(0.189±0.007)、Adv0-CD4+T细胞组(0.419±0.014)及第三方供者抗原组(0.200±0.008),差异有统计学意义(P<0.05).结论 转染IKK2dn并负载

  20. Suppressor cell hyperactivity relative to allogeneic lymphocyte proliferation as a manifestation of defective T-T-cell interactions in systemic lupus erythematosus

    International Nuclear Information System (INIS)

    The authors study the state of immunoregulatory process in patients with systemic lupus erythematosus at the T-T-cell interaction level and seek to test the possibility of the pharmacological modulation of this process. The proliferative activity of mononuclear lymphocytes, extracted from the blood of ten lupus patients, was assessed by measuring the incorporation of tritiated thymidine into cultures stimulated by phytohemagglutinin, concanavalin, and theophylline. The comparative effects of each of these agents on the immunoregulatory and proliferative activity of the lymphocytes are reported

  1. Soluble interleukin-2 receptors inhibit interleukin 2-dependent proliferation and cytotoxicity: explanation for diminished natural killer cell activity in cutaneous T-cell lymphomas in vivo?

    OpenAIRE

    Dummer, R.; Posseckert, G.; F. NESTLE; Witzgall, R.; Burger, M.; Becker, J C; Schäfer, E; Wiede, J.; Sebald, Walter; Burg, G

    2012-01-01

    In patients with cutaneous T-cell lymphomas (CTCL), soluble interleukin-2 receptor serum levels (sIL-2R) were determined by ELISA technique, and natural killer cell (NK) activity, by a 4-h chromium-51 release assay. Decrease of NK activity correlated with the augmentation of serum sIL-2R. After a 4-d stimulation with interleukin 2 CTCL patients' peripheral mononuclear cells (PMC) showed an increase of cytotoxic activity similar to that in healthy donors' PMC. Normal donors' PMC demonstrated a...

  2. Suppressor cell hyperactivity relative to allogeneic lymphocyte proliferation as a manifestation of defective T-T-cell interactions in systemic lupus erythematosus

    Energy Technology Data Exchange (ETDEWEB)

    Stenina, M.A.; Potapova, A.A.; Biryukov, A.V.; Skripnik, A.Yu.; Cheredeev, A.N.

    1987-01-01

    The authors study the state of immunoregulatory process in patients with systemic lupus erythematosus at the T-T-cell interaction level and seek to test the possibility of the pharmacological modulation of this process. The proliferative activity of mononuclear lymphocytes, extracted from the blood of ten lupus patients, was assessed by measuring the incorporation of tritiated thymidine into cultures stimulated by phytohemagglutinin, concanavalin, and theophylline. The comparative effects of each of these agents on the immunoregulatory and proliferative activity of the lymphocytes are reported.

  3. 大青叶等清热药对HaCaT细胞增殖的影响%Effect of Chinese Herbs with Properties of Clearing away Heat on the Proliferation of HaCaT Cells

    Institute of Scientific and Technical Information of China (English)

    郑明警; 马丽俐

    2013-01-01

      目的:观察单味清热类中药大青叶、水牛角、龙胆草、生地、黄芩提取物对HaCaT细胞增殖的影响.方法:用MTT法检测上述单味清热类中药提取物对HaCat细胞的24h抑制率.结果:大青叶、龙胆草、黄芩、生地提取物具有抑制HaCaT细胞增殖作用,且与药物浓度具有一定相关性;水牛角提取物具有促进HaCaT细胞增殖作用,且与药物浓度具有一定相关性,与空白对照组比较差异具有统计学意义(P<0.05).结论:抑制角质形成细胞增殖可能是大青叶、生地、黄芩、龙胆草治疗银屑病的作用机制之一,水牛角治疗银屑病的作用与抑制角质形成细胞增殖无关.%Objective: To investigate the influence of folium, buffalo horn, gentian, habitat, and skullcap extracts on the proliferation of HaCaT cells. Methods: The 24h inhibitory rate of HaCaT cell proliferation by the above mentioned Chinese herbs was examined by the MTT method. Results: Folium, gentian, skullcap, and habitat ex⁃tracts inhibited the proliferation of HaCaT cells in a dose-dependent manner, while buffalo horn extract advanced the proliferation of the cells in a dose-dependent manner, and these results were all significantly different as compared to blank control groups(P<0.05). Conclusion: One of the mechanisms by which folium, buffalo horn, gentian, and skullcap treat psoriasis may be inhibiting the proliferation of malpighian cells, while buffalo horn does not have the same effect when being used to treat psoriasis.

  4. Intracellular Signals of T Cell Costimulation

    Institute of Scientific and Technical Information of China (English)

    Jianxun Song; Fengyang Tylan Lei; Xiaofang Xiong; Rizwanul Haque

    2008-01-01

    Ligation of T cell receptor (TCR) alone is insufficient to induce full activation of T lymphocytes. Additional ligand-receptor interactions (costimulation) on antigen presenting cells (APCs) and T cells are required. T cell costimulation has been shown to be essential for eliciting efficient T cell responses, involving all phases during T cell development. However, the mechanisms by which costimulation affects the function of T cells still need to be elucidated. In recent years, advances have been made in studies of costimulation as potential therapies in cancer, infectious disease as well as autoimmune disease. In this review, we discussed intracellular costimulation signals that regulate T cell proliferation, cell cycle progression, cytokine production, survival, and memory development. In general, the pathway of phosphoinositide-3 kinase (PBK)/protein kinase B (PKB, also known as Akt)/nuclear factor κB (NF-κB) might be central to many costimulatory effects. Through these pathways, costimulation controls T-cell expansion and proliferation by maintenance of survivin and aurora B expression, and sustains long-term T-cell survival and memory development by regulating the expression of bci-2 family members. Cellular & Molecular Immunology.2008;5(4):239-247.

  5. Direct Interaction of CD40 on Tumor Cells with CD40L on T Cells Increases the Proliferation of Tumor Cells by Enhancing TGF-β Production and Th17 Differentiation.

    Directory of Open Access Journals (Sweden)

    Hyemin Kim

    Full Text Available It has recently been reported that the CD40-CD40 ligand (CD40L interaction is important in Th17 development. In addition, transforming growth factor-beta (TGF-β promotes tumorigenesis as an immunosuppressive cytokine and is crucial in the development of Th17 cells. This study investigated the role of CD40 in breast cancer cells and its role in immunosuppressive function and tumor progression. CD40 was highly expressed in the breast cancer cell line MDA-MB231, and its stimulation with CD40 antibodies caused the up-regulation of TGF-β. Direct CD40-CD40L interaction between MDA-MB231 cells and activated T cells also increased TGF-β production and induced the production of IL-17, which accelerated the proliferation of MDA-MB231 cells through the activation of STAT3. Taken together, the direct CD40-CD40L interaction of breast tumor cells and activated T cells increases TGF-β production and the differentiation of Th17 cells, which promotes the proliferation of breast cancer cells.

  6. Human iPSC-derived mesoangioblasts, like their tissue-derived counterparts, suppress T cell proliferation through IDO- and PGE-2-dependent pathways [v1; ref status: indexed, http://f1000r.es/x3

    Directory of Open Access Journals (Sweden)

    Ou Li

    2013-01-01

    Full Text Available Human mesoangioblasts are currently in a phase I/II clinical trial for the treatment of patients with Duchenne muscular dystrophy. However, limitations associated with the finite life span of these cells combined with the significant numbers of mesoangioblasts required to treat all of the skeletal muscles in these patients restricts their therapeutic potential. Induced pluripotent stem cell (iPSC-derived mesoangioblasts may provide the solution to this problem. Although, the idea of using iPSC-derived cell therapies has been proposed for quite some time, our understanding of how the immune system interacts with these cells is inadequate. Herein, we show that iPSC-derived mesoangioblasts (HIDEMs from healthy donors and, importantly, limb-girdle muscular dystrophy 2D patients exert immunosuppressive effects on T cell proliferation.  Interferon gamma (IFN-γ and tumour necrosis factor alpha (TNF-α play crucial roles in the initial activation of HIDEMs and importantly indoleamine 2,3 dioxygenase (IDO and prostaglandin E2 (PGE-2 were identified as key mechanisms involved in HIDEM suppression of T cell proliferation. Together with recent studies confirming the myogenic function and regenerative potential of these cells, we suggest that HIDEMs could provide an unlimited alternative source for mesoangioblast-based therapies.

  7. 1,25-Dihydroxyvitamin D3 inhibits proliferation but not the suppressive function of regulatory T cells in the absence of antigen-presenting cells.

    NARCIS (Netherlands)

    Khoo, A.L.; Joosten, I.; Michels, M.; Woestenenk, R.M.; Preijers, F.W.M.B.; He, X.; Netea, M.G.; Ven, A.J.A.M. van der; Koenen, H.J.P.M.

    2011-01-01

    Vitamin D3 is known to induce regulatory T (Treg) cells by rendering antigen-presenting cells tolerogenic, its direct effect on human naturally occurring Treg cells is unclear. Here, we investigated if and how 1,25-dihydroxyvitamin D(3) [1,25(OH)2D3] can directly affect the proliferation and functio

  8. Genetic evidence that intratumoral T-cell proliferation and activation is associated with recurrence and survival in patients with resected colorectal liver metastases

    OpenAIRE

    Maker, Ajay V; Ito, Hiromichi; Mo, Qianxing; Weisenberg, Elliot; Qin, Li-Xuan; Turcotte, Simon; Maithel, Shishir; Shia, Jinru; Blumgart, Leslie; Fong, Yuman; Jarnagin, William R; DeMatteo, Ronald P.; D'Angelica, Michael I.

    2015-01-01

    Though immune responses correlate with prognosis in primary colorectal cancer, the role of tumor immunity in metastatic disease is less clear. We hypothesized that patient survival and tumor recurrence correlate with transcriptional evidence of lymphocyte proliferation/activation in resected colorectal cancer liver metastases (CRLM). Microarray gene analysis was performed on liver tumor specimens from 96 patients who underwent resection for CRLM. A Cox proportional hazards model identified ge...

  9. T Cells Going Innate.

    Science.gov (United States)

    Seyda, Midas; Elkhal, Abdallah; Quante, Markus; Falk, Christine S; Tullius, Stefan G

    2016-08-01

    Natural killer (NK) cell receptors (NKRs) play a crucial role in the homeostasis of antigen-experienced T cells. Indeed, prolonged antigen stimulation may induce changes in the receptor repertoire of T cells to a profile that features NKRs. Chronic antigen exposure, at the same time, has been shown to trigger the loss of costimulatory CD28 molecules with recently reported intensified antigen thresholds of antigen-experienced CD8(+) T cells. In transplantation, NKRs have been shown to assist allograft rejection in a CD28-independent fashion. We discuss here a role for CD28-negative T cells that have acquired the competency of the NKR machinery, potentially promoting allorecognition either through T cell receptor (TCR) crossreactivity or independently from TCR recognition. Collectively, NKRs can bring about innate-like T cells by providing alternative costimulatory pathways that gain relevance in chronic inflammation, potentially leading to resistance to CD28-targeting immunosuppressants. PMID:27402226

  10. Repeated 0.5 Gy gamma-ray irradiation attenuates autoimmune disease in MRL-lpr/lpr mice with up-regulation of regulatory T cells

    International Nuclear Information System (INIS)

    Complete text of publication follows. MRL-lpr/lpr mice present a single gene mutation on the Fas (CD95) gene that leads to reduced signaling for apoptosis. With aging, these mice spontaneously develop autoimmune disease and are used as a model of systemic lupus erythematosus. We previously reported attenuation of autoimmune disease in MRL-lpr/lpr mice by repeated γ-ray irradiation (0.5 Gy each time). In this study, we investigated the mechanisms of this attenuation focusing the highly activated CD3+CD4-CD8-B220+ T cells, which are characteristically involved in autoimmune pathology in these mice. We measured the weight of the spleen and the population of CD3+CD4-CD8-B220+ T cells. Splenomegaly and increase in percentage of CD3+CD4-CD8-B220+ T cells, which occur with aging in non-irradiated mice, were suppressed in irradiated mice. To investigate the function of CD3+CD4-CD8-B220+ T cells, we isolated these cells from splenocytes by magnetic cell sorting. Isolated CD3+CD4-CD8-B220+ T cells were more resistant to irradiation-induced cell death than isolated CD4+ T cells. Although high proliferation rate and IL-6 production were observed in isolated CD3+CD4-CD8-B220+ T cells, the proliferation rate and IL-6 production were lower in the cells isolated from the irradiated mice. Moreover, the production of autoantibodies (anti-collagen antibody and anti-single strand DNA antibody) was also lowered by irradiation. These results indicate that activation of CD3+CD4-CD8-B220+ T cells and progression of pathology would be suppressed by repeated 0.5 Gy γ-ray irradiation. To uncover the mechanism of the immune suppression, we analyzed population of regulatory T cells (CD4+CD25+Foxp3+), which suppress activated T cells and excessive autoimmune responses. Intriguingly, significant increase of the percentage of regulatory T cells was observed in irradiated mice. In conclusion, we found that repeated 0.5 Gy γ-ray irradiation suppresses proliferation rate of CD3+CD4-CD8-B220+ T

  11. Catharanthus roseus Aqueous Extract is Cytotoxic to Jurkat Leukaemic T-cells but Induces the Proliferation of Normal Peripheral Blood Mononuclear Cells

    Science.gov (United States)

    Ahmad, Nor Hazwani; Rahim, Rohanizah Abdul; Mat, Ishak

    2010-01-01

    Research on natural products has been widely used as a strategy to discover new drugs with potential for applications in complementary medicines because they have fewer side effects than conventional drugs. The aim of the present study was to evaluate the in vitro cytotoxic effects of crude aqueous Catharanthus roseus extract on Jurkat cells and normal peripheral blood mononuclear cells (PBMCs). The aqueous extract was standardised to vinblastine by high performance liquid chromatography (HPLC) and was used to determine cytotoxicity by the MTS [3-(4,5-dimethylthiazol-2-yl)-5(3-carboxymethoxyphenyl)-2-(4-sulfophenyl)-2H-tetrazolium] assay. DNA fragmentation assay was employed to determine if cell death was due to apoptosis. The results showed that the aqueous extract induced cell death of Jurkat cells at 24, 48 and 72 hours post-treatment in a time- and dose-dependent manner. However, cells treated at 48 and 72 hours produced higher cytotoxic effects with half maximal inhibitory concentration (IC50) values of 2.55 μg/ml and 2.38 μg/ml, respectively. In contrast, the extract induced normal PBMC proliferation, especially after 24 hours treatment with 1000 μg/ml. This result indicates that the C. roseus crude aqueous extract showed differential effects of inhibiting the proliferation of the Jurkat cell line and promoting the growth of PBMCs. These data suggest that the extract may be applicable for modulating the normal and transformed immune cells in leukaemia patients. PMID:24575203

  12. Effect of normal human skin-derived mesenchymal stem cells on HaCaT cell proliferation%健康人皮肤间充质干细胞对HaCaT细胞增殖作用的研究

    Institute of Scientific and Technical Information of China (English)

    王建华; 张开明; 刘瑞风; 甄莉

    2015-01-01

    Objective To investigate the effect of normal human skin-mesenchymal stem cells (S-MSCs) on HaCaT cell proliferation, so as to provide a theoretical basis for the role of S-MSCs in pathologic status. Methods Twenty cases of normal skin were harvested from surgically removed fresh redundant skin by courtesy of cosmetics and urology departments in our hospital. Under sterile conditions, the epidermal and dermal layers were separated, and the dermal MSCs were isolated and cultured. Flow cytometry was used to identify the MSCs and the multi-direc-tional differentiation and differentiated cells. The fifth passage of S-MSCs was co-cultured with HaCaT cells, and com-pared with the naturally proliferating S-MSCs. Real-time cell analysis system was employed to examine the HaCaT cell proliferation. At 72h after culture, the number of HaCaT cells was observed by cell counting. Results Under inverted phase contrast microscope, the normal human S-MSCs was slender and spindle cells with high expression of surface antigens CD29, CD44, CD73, CD90, and CD105, and negative expression of CD34, CD45 and HLA-DR. The S-MSCs could be induced to differentiate into adipocytes, osteoblasts and chondroblasts. The number of naturally cultured Ha-CaT cells was (2.74±0.36)×105, compared with (2.24±0.28)×105 for the number of HaCaT cells co-cultured with normal human S-MSCs. The difference was statistically significant (P<0.001). Conclusion Normal human skin-derived MSCs could inhibit the proliferation of HaCaT cells in vitro.%目的:探讨健康人皮肤间充质干细胞(S-MSCs)对HaCaT细胞增殖的作用,为研究S-MSCs在病理状态下的作用提供理论依据。方法健康人皮肤20份,均取自我院整形和泌尿外科手术切除的多余新鲜皮肤组织。在体外无菌条件下进行真表皮分离、培养真皮MSCs,流式细胞术进行细胞鉴定,多向诱导分化及分化细胞的鉴定,将培养至第5代的S-MSCs与HaCaT细胞共培养,并与

  13. T cell priming: let there be light

    Institute of Scientific and Technical Information of China (English)

    Ludmila Jirmanova; Jonathan D Ashwell

    2010-01-01

    @@ Activation of naive T cells via the T cell receptor (TCR) induces proliferation, gain of effector functions, and ultimately the development of long-lived memory cells. Memory cells have lower thresholds of activation than naive cells and respond more robustly to similar degrees of stimulation, which are fundamental properties of adaptive immunity. TCR occupancy leads to phosphorylation of TCR-ζ and CD3 cytoplasmic tails by Lck and Fyn, recruitment of ζ-associated protein kinase 70 (ZAP70), and phosphorylation/acti-vation of downstream targets such as the linker for activation of T cells (LAT) and SLP-76 [1].

  14. 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......) 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 but not...

  15. Neurohypophysial Receptor Gene Expression by Thymic T Cell Subsets and Thymic T Cell Lymphoma Cell Lines

    Directory of Open Access Journals (Sweden)

    I. Hansenne

    2004-01-01

    transcribed in thymic epithelium, while immature T lymphocytes express functional neurohypophysial receptors. Neurohypophysial receptors belong to the G protein-linked seven-transmembrane receptor superfamily and are encoded by four distinct genes, OTR, V1R, V2R and V3R. The objective of this study was to identify the nature of neurohypophysial receptor in thymic T cell subsets purified by immunomagnetic selection, as well as in murine thymic lymphoma cell lines RL12-NP and BW5147. OTR is transcribed in all thymic T cell subsets and T cell lines, while V3R transcription is restricted to CD4+ CD8+ and CD8+ thymic cells. Neither V1R nor V2R transcripts are detected in any kind of T cells. The OTR protein was identified by immunocytochemistry on thymocytes freshly isolated from C57BL/6 mice. In murine fetal thymic organ cultures, a specific OTR antagonist does not modify the percentage of T cell subsets, but increases late T cell apoptosis further evidencing the involvement of OT/OTR signaling in the control of T cell proliferation and survival. According to these data, OTR and V3R are differentially expressed during T cell ontogeny. Moreover, the restriction of OTR transcription to T cell lines derived from thymic lymphomas may be important in the context of T cell leukemia pathogenesis and treatment.

  16. 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...

  17. Roscovitine suppresses CD4+ T cells and T cell-mediated experimental uveitis.

    Directory of Open Access Journals (Sweden)

    Zili Zhang

    Full Text Available BACKGROUND: T cells are essential for the development of uveitis and other autoimmune diseases. After initial activation, CD4+ lymphocytes express the co-stimulatory molecule OX40 that plays an important role in T cell proliferation. Cyclin dependent kinase 2 (CdK2 plays a pivotal role in the cell cycle transition from G1 to S phase. In addition, recent research has implicated CdK2 in T cell activation. Thus, we sought to test the immunosuppressive effect of roscovitine, a potent CdK2 inhibitor, on CD4+ T cell activation, proliferation, and function. DESIGN AND METHODS: Mouse CD4+ T cells were activated by anti-CD3 and anti-CD28 antibodies. The expression of OX40, CD44, and CdK2 were analyzed by flow cytometry. In addition, cell cycle progression and apoptosis of control and roscovitine-treated T lymphocytes were measured by BrdU incorporation and annexin V assay, respectively. Furthermore, the immunoregulatory effect of roscovitine was evaluated in both ovalbumin-induced uveitis and experimental autoimmune uveitis (EAU models. RESULTS: In this study, we found that T cell activation induced OX40 expression. Cell cycle analysis showed that more CD4+OX40+ cells entered S phase than OX40- T cells. Concurrently, CD4+OX40+ cells had a higher level of CdK2 expression. Roscovitine treatment blocked activated CD4+ cells from entering S phase. In addition, roscovitine not only reduced the viability of CD4+ lymphocytes but also suppressed T cell activation and cytokine production. Finally, roscovitine significantly attenuated the severity of T cell-dependent, OX40-enhanced uveitis. CONCLUSION: These results implicate CdK2 in OX40-augmented T cell response and expansion. Furthermore, this study suggests that roscovitine is a novel, promising, therapeutic agent for treating T cell-mediated diseases such as uveitis.

  18. Improved anti-leukemia activities of adoptively transferred T cells expressing bispecific T-cell engager in mice.

    Science.gov (United States)

    Liu, X; Barrett, D M; Jiang, S; Fang, C; Kalos, M; Grupp, S A; June, C H; Zhao, Y

    2016-01-01

    Despite the impressive clinical efficacy of T cells engineered to express chimeric antigen receptors (CAR-Ts), the current applications of CAR-T cell therapy are limited by major treatment-related toxicity. Thus, safer yet effective alternative approaches must be developed. In this study, we compared CD19 bispecific T-cell engager (BiTE)-transferred T cells that had been transfected by RNA electroporation with CD19 CAR RNA-transferred T cells both in vitro and in an aggressive Nalm6 leukemia mouse model. BiTEs were secreted from the transferred T cells and enabled both the transferred and bystander T cells to specifically recognize CD19(+) cell lines, with increased tumor killing ability, prolonged functional persistence, increased cytokine production and potent proliferation compared with the CAR-T cells. More interestingly, in comparison with CD3/CD28 bead-stimulated T cells, T cells that were expanded by a rapid T-cell expansion protocol (REP) showed enhanced anti-tumor activities for both CAR and BiTE RNA-electroporated T cells both in vitro and in a Nalm6 mouse model (P<0.01). Furthermore, the REP T cells with BiTE RNAs showed greater efficacy in the Nalm6 leukemia model compared with REP T cells with CAR RNA (P<0.05) and resulted in complete leukemia remission. PMID:27258611

  19. The E3 ubiquitin ligase GRAIL regulates T cell tolerance and regulatory T cell function by mediating T cell receptor-CD3 degradation

    OpenAIRE

    Nurieva, Roza I.; Zheng, Shuling; Jin, Wei; Chung, Yeonseok; Zhang, Yongliang; Martinez, Gustavo J.; Reynolds, Joseph M.; Wang, Sung-Ling; Lin, Xin; Sun, Shao-Cong; Lozano, Guillermina; Dong, Chen

    2010-01-01

    T cell activation is tightly regulated to avoid autoimmunity. Gene related to anergy in lymphocytes (GRAIL, encoded by Rnf128) is an E3 ubiquitin ligase associated with T cell tolerance. Here we generated and analyzed GRAIL-deficient mice and found they were resistant to immune tolerance induction and exhibited greater susceptibility to autoimmune diseases than wild-type mice. GRAIL-deficient naïve T cells, after activation, exhibited increased proliferation and cytokine expression than contr...

  20. CD4+CD45RBHi Interleukin-4 Defective T Cells Elicit Antral Gastritis and Duodenitis

    OpenAIRE

    Dohi, Taeko; Fujihashi, Kohtaro; Koga, Toshiya; Etani, Yuri; Yoshino, Naoto; Kawamura, Yuki I.; Mcghee, Jerry R

    2004-01-01

    We have analyzed the gastrointestinal inflammation which develops following adoptive transfer of IL-4 gene knockout (IL-4−/−) CD4+CD45RBHi (RBHi) T cells to severe combined immunodeficient (SCID) or to T cell-deficient, T cell receptor β and δ double knockout (TCR−/−) mice. Transfer of IL-4−/− RBHi T cells induced a similar type of colitis to that seen in SCID or TCR−/− recipients of wild-type (wt) RBHi T cells as reported previously. Interestingly, transfer of both wt and IL-4−/− RBHi T cell...

  1. Auto-presentation of Staphylococcal enterotoxin A by mouse CD4+ T cells

    Science.gov (United States)

    The currently accepted model for superantigen (SAg )induced T cell activation suggests that SAg, without being processed, cross links both MHC class II, from Antigen Presenting Cells (APC), and V-beta, from T-cell receptor (TCR), initiating nonspecific T-cell activation. This T-cell proliferation in...

  2. T cell traffic signals

    OpenAIRE

    Van Epps, Heather L.

    2005-01-01

    In 1990, Charles Mackay and colleagues combined classical physiology with modern molecular biology to provide the first concrete evidence that naive and memory T cells follow distinct migratory routes out of the bloodstream— a discovery that helped invigorate the field of lymphocyte homing.

  3. T-cell costimulation

    DEFF Research Database (Denmark)

    Owens, T

    1996-01-01

    The CD40L molecule expressed by CD4+ regulatory T lymphocytes is known to deliver signals that activate B cells and macrophages. It now appears that CD40L regulates T cells themselves, during both their development and their participation in adaptive immune responses....

  4. 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...

  5. The self-antigen, thyroglobulin, induces antigen-experienced CD4+ T cells from healthy donors to proliferate and promote production of the regulatory cytokine, interleukin-10, by monocytes

    DEFF Research Database (Denmark)

    Nielsen, Claus Kim Hostein; Galdiers, Marcel P; Hedegaard, Chris Juul;

    2010-01-01

    monocytes were prime producers of IL-10 in the early TG response, a few IL-10-secreting CD4(+) T cells, primarily with CD45RO(+) memory phenotype, were also detected. Furthermore, T-cell depletion from the mononuclear cell preparation abrogated monocyte IL-10 production. Our findings indicate active...

  6. 体外培养扩增CD4+CD25+调节性T细胞的实验观察%Proliferation of CD4+CD25+ regulatory T cells of rat by different cytokines in vitro

    Institute of Scientific and Technical Information of China (English)

    王子函; 朱继业; 李涛; 冷希圣

    2008-01-01

    Objective To evaluate the effects of cytokines on tlle proliferation and function of CD4+CD25+ regulatory T cell(Treg).Mellaotis Tregs were isolated from na(i)ve C57BL/6 mice spleen and lymph nodes.Mature dendritic cells(mDC)were isolated from DBA/2 mice,co-cultured with Tregs,and divided into 4 groups with or without interleukin-2(IL-2),interleukin-4(IL-4),and interleukin-15(IL-15)added into the culture fluid.Fluorescence.activated cell sorting(FACS)was used to detect the Treg proliferation and apoptosis with CFSE and annexin-V staining.The co-cuhure increased Tregs were divided into 5 groups:CFSE labeled naive CIM+ CD25-T cells,self-proliferated Treg,Treg mixedly cultured with IL-2 mDC,and Teff,Treg mixedly cultured with IL-4,mDC,and Teff,and Treg mixedly cultured with IL-15,mDC,and Teff,a control group included Teff co-cultured with mDC.FACS was used 5 d later to evalugte the suppressive function of the Treg Oil the Teff. The expression of Foxp3,indicating the phenotype of Treg was detected.Results FASC showed that the values of precursor frequency(PF)of the Tregs stimulated by IL-2,IL-4,and IL-15 were 31.3%,28.9%,and 34.5%respectively,all significantly higher than that of the control group(14.5% all P<0.05),and the values of proliferation index(PI)of the Tregs stimulated by IL-2,IL-4,and IL-15 were 1.9,1.7,and 1.8 respectively,all significantly higher than that of the control group(1.5,all P<0.05).,The apoptotic rates of the Tregs stimulated by IL-2,IL-4,and IL-15 were 12.8%,11.4%,and 12.7% respectively,all signifieanfly lower tllan that of the control group(28.9%,P<0.05).The Foxp3 expression rate of the Tregs stimulated by IL-2,IL-4,and IL-15was 91.75%.Conclusion IL-2.IL-4.and IL-15 in the in vitro culture of Treg stimulate the Treg proliferation,reduce tlleir apoptosis,and maintain their suppressive function.The proliferated Tregs still maintain their phenotype,highly expressing Foxp3.%目的 观察细胞因子体外培养扩增CD4+CD25+调节性T细

  7. Change of paradigm: CD8+ T cells as important helper for CD4+ T cells during asthma and autoimmune encephalomyelitis

    OpenAIRE

    Huber, Magdalena; Lohoff, Michael

    2015-01-01

    Summary The activation of naive CD4+ and CD8+ T cells in response to antigen and their subsequent proliferation and differentiation into effectors are important features of a cell-mediated immune response. CD4+ T cells (also known as T helper cells, Th) differentiate into several subpopulations including Th1, Th2, Th9, Th17, Tfh and Treg cells, characterized by specific cytokine profiles and effector functions. However, recent evidence indicates that CD8+ T cells (termed cytotoxic T lymphocyt...

  8. Contribution of Herpesvirus Specific CD8 T Cells to Anti-Viral T Cell Response in Humans

    OpenAIRE

    Elena Sandalova; Diletta Laccabue; Carolina Boni; Tan, Anthony T.; Katja Fink; Eng Eong Ooi; Robert Chua; Bahar Shafaeddin Schreve; Carlo Ferrari; Antonio Bertoletti

    2010-01-01

    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, 1...

  9. 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…

  10. CD27(-)CD45(+) γδ T cells can be divided into two populations, CD27(-)CD45(int) and CD27(-)CD45(hi) with little proliferation potential.

    Science.gov (United States)

    Odaira, Kosuke; Kimura, Shin-Nosuke; Fujieda, Nao; Kobayashi, Yukari; Kambara, Kaori; Takahashi, Takuya; Izumi, Takamichi; Matsushita, Hirokazu; Kakimi, Kazuhiro

    2016-09-23

    In addition to the majority of T cells which carry the αβ T cell receptor (TCR) for antigen, a distinct subset of about 1-5% of human peripheral blood T cells expressing the γδ TCR contributes to immune responses to infection, tissue damage and cancer. T cells with the Vδ2(+) TCR, usually paired with Vγ9, constitute the majority of these γδ T cells. Analogous to αβ T cells, they can be sorted into naive (CD27(+)CD45RA(+)), central memory (CD27(+)CD45RA(-)), effector memory (CD27(-)CD45RA(-)), and terminally-differentiated effector memory (CD27(-)CD45RA(+)) phenotypes. Here, we found that CD27(-)CD45RA(+) γδ T cells can be further divided into two populations based on the level of expression of CD45RA: CD27(-)CD45RA(int) and CD27(-)CD45RA(hi). Those with the CD27(-)CD45RA(hi) phenotype lack extensive proliferative capacity, while those with the CD27(-)CD45RA(int) phenotype can be easily expanded by culture with zoledronate and IL-2. These CD27(-)CD45RA(hi) potentially exhausted γδ T cells were found predominantly in cancer patients but also in healthy subjects. We conclude that γδ T cells can be divided into at least 5 subsets enabling discrimination of γδ T cells with poor proliferative capacity. It was one of our goals to predict the feasibility of γδ T cell expansion to sufficient amounts for adoptive immunotherapy without the necessity for conducting small-scale culture tests. Fulfilling the ≥1.5% criterion for γδ T cells with phenotypes other than CD27(-)CD45RA(hi), may help avoid small-scale culture testing and shorten the preparation period for adoptive γδ T cells by 10 days, which may be beneficial for patients with advanced cancer.

  11. The immunological characteristics of CD8+ CD28- suppressor T cells induced by siRNA technique%利用RNA干扰诱导产生的CD8+CD28-抑制性T淋巴细胞的免疫学特性

    Institute of Scientific and Technical Information of China (English)

    薛利军; 彭承宏; 李宏为; 尹路; 陈春球; 张贵阳; 孙广涛; 杜海磊; 倪俊声; 陈雪华; 林谋斌

    2009-01-01

    逆转,且其免疫调节作用具有抗原特异性.%Objective To induce CD8+ CD28- suppressor T cells(CD8+Ts)by DC with MHCⅠ expression by siRNA,under the stimulator of allograft antigen and then investigate the immunological characteristics of Ts.Methods After the isolation and cultivation of DCs from femoral bone of SI)rats.the optimal sequence of MHCⅠ siRNA was designed and constructed,and the MHC Ⅰ siRNA was transfected into DCs.The IX3s were stimulated by mesenteric lymphatic tissue fluid of Wistar rats.and then co-cultured with CD8+ Ts isolated from SD rat spleen.SD rat CD8+T cells were ohtained by magnetic separation method.Cell proliferation was assayed after SD rat spleen cells loading Wistar rat mesenteric lymph node tissue antigen reacted with different amount of Ts.After SD rat spleen cells were stimulated by Wismr rat's mesenteric lymph node and reacted with OVA respectively.different amounts of Ts were added.Gell proliferation of the spleen lymphocytes in different groups was assayed, rrIL-2 was added to the mixed lymphocyte culture system containing Wistar rat's mesenteric lymph node tissue antigen, SD rat's Ts and SD rat spleen lymphocytes, then the influence of the IL-2 on the function of SD rat Ts was observed. The expression of TGF-β and IFN-γ mRNA was examined by Real time PCR, and CD25 was detected by Real time-PCR and flow cytometry in CD8+ CD28- T cells group. Results Ts had inhibitory influence on the mixed lymphocytes proliferation between SD rat' s spleen lymphocytes and Wistar rat's mesenteric lymph node tissue, but exerted no efforts on the mixed lymphocytes proliferation between OVA and SD rat's spleen lymphocytes. After addition of rrIL-2 into the mixed lymphocyte culture system containing Wistar rat mesenterie lymph node tissue antigen and Ts, there was no significant increase in the mixed lymphocytes proliferation of SD rat spleen lymphocytes (P>0. 05). The expression levels of TGF-βand IFN-γ mRNA were higher in CD8 + CD

  12. Activated Human T Cells Secrete Exosomes That Participate in IL-2 Mediated Immune Response Signaling

    OpenAIRE

    Wahlgren, Jessica; Tanya De L Karlson; Glader, Pernilla; Telemo, Esbjörn; Valadi, Hadi

    2012-01-01

    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, c...

  13. Interleukin-2 Enhances the Regulatory Functions of CD4(+)T Cell-Derived CD4(-)CD8(-) Double Negative T Cells.

    Science.gov (United States)

    Cong, Min; Liu, Tianhui; Tian, Dan; Guo, Hongbo; Wang, Ping; Liu, Kai; Lin, Jun; Tian, Yue; Shi, Wen; You, Hong; Jia, Jidong; Zhang, Dong

    2016-08-01

    CD4(+) T cells can be converted to CD4(-)CD8(-) double negative T cells (DN T cells) under appropriate conditions, and IL-2 enhanced the conversion. Here, we investigated the effect of IL-2 on the proliferation and function of converted DN T cells in vitro and in vivo. DN T cells were hyporesponsive when restimulated by mature dendritic cells (mDCs), IL-2 completely restored their responsiveness in vitro. In addition, IL-2 increased the resistance of DN T cells to apoptosis in vivo. DN T cells profoundly inhibited the proliferation of CD4(+)CD25(-) T effector cells triggered by mDCs in vitro, and this suppression was further enhanced by IL-2. Adoptively transferring of DN T cells, in combination with IL-2, inhibited the proliferation and enhanced apoptosis of alloreactive CD4(+) T cells, which resulted in significant prolongation of skin allograft survival time. Perforin plays a key role in the enhancement of DN T cells immune regulation by IL-2. In conclusion, we elucidated that IL-2 promoted DN T cell proliferation and suppressive function. The combination of DN T cells and exogenous IL-2 may represent a novel therapy in the clinical setting to prevent allograft rejection and induce immune tolerance. PMID:27135902

  14. Ectopic expression of anti-HIV-1 shRNAs protects CD8{sup +} T cells modified with CD4ζ CAR from HIV-1 infection and alleviates impairment of cell proliferation

    Energy Technology Data Exchange (ETDEWEB)

    Kamata, Masakazu, E-mail: masa3k@ucla.edu [Division of Hematology-Oncology, David Geffen School of Medicine at UCLA, Los Angeles, CA (United States); Kim, Patrick Y. [Department of Microbiology, Immunology, and Molecular Genetics, David Geffen School of Medicine at UCLA, Los Angeles, CA (United States); Ng, Hwee L. [Division of Infectious Diseases, David Geffen School of Medicine at UCLA, Los Angeles, CA (United States); Ringpis, Gene-Errol E.; Kranz, Emiko; Chan, Joshua; O' Connor, Sean [Department of Microbiology, Immunology, and Molecular Genetics, David Geffen School of Medicine at UCLA, Los Angeles, CA (United States); Yang, Otto O. [Department of Microbiology, Immunology, and Molecular Genetics, David Geffen School of Medicine at UCLA, Los Angeles, CA (United States); Division of Infectious Diseases, David Geffen School of Medicine at UCLA, Los Angeles, CA (United States); UCLA AIDS Institute, Los Angeles, CA (United States); AIDS Healthcare Foundation, Los Angeles, CA (United States); Chen, Irvin S.Y. [Division of Hematology-Oncology, David Geffen School of Medicine at UCLA, Los Angeles, CA (United States); Department of Microbiology, Immunology, and Molecular Genetics, David Geffen School of Medicine at UCLA, Los Angeles, CA (United States); UCLA AIDS Institute, Los Angeles, CA (United States)

    2015-07-31

    Chimeric antigen receptors (CARs) are artificially engineered receptors that confer a desired specificity to immune effector T cells. As an HIV-1-specific CAR, CD4ζ CAR has been extensively tested in vitro as well as in clinical trials. T cells modified with this CAR mediated highly potent anti-HIV-1 activities in vitro and were well-tolerated in vivo, but exerted limited effects on viral load and reservoir size due to poor survival and/or functionality of the transduced cells in patients. We hypothesize that ectopic expression of CD4ζ on CD8{sup +} T cells renders them susceptible to HIV-1 infection, resulting in poor survival of those cells. To test this possibility, highly purified CD8{sup +} T cells were genetically modified with a CD4ζ-encoding lentiviral vector and infected with HIV-1. CD8{sup +} T cells were vulnerable to HIV-1 infection upon expression of CD4ζ as evidenced by elevated levels of p24{sup Gag} in cells and culture supernatants. Concurrently, the number of CD4ζ-modified CD8{sup +} T cells was reduced relative to control cells upon HIV-1 infection. To protect these cells from HIV-1 infection, we co-expressed two anti-HIV-1 shRNAs previously developed by our group together with CD4ζ. This combination vector was able to suppress HIV-1 infection without impairing HIV-1-dependent effector activities of CD4ζ. In addition, the number of CD4ζ-modified CD8{sup +} T cells maintained similar levels to that of the control even under HIV-1 infection. These results suggest that protecting CD4ζ-modified CD8{sup +} T cells from HIV-1 infection is required for prolonged HIV-1-specific immune surveillance. - Highlights: • Ectopic expression of CD4ζ CAR in CD8{sup +} T cells renders them susceptible to HIV-1 infection. • Co-expression of two anti-HIV-1 shRNAs protects CD4ζ CAR-modified CD8{sup +} T cells from HIV-1 infection. • Protecting CD4ζ CAR-modified CD8{sup +} T cells from HIV-1 infection suppresses its cytopathic effect.

  15. Ectopic expression of anti-HIV-1 shRNAs protects CD8+ T cells modified with CD4ζ CAR from HIV-1 infection and alleviates impairment of cell proliferation

    International Nuclear Information System (INIS)

    Chimeric antigen receptors (CARs) are artificially engineered receptors that confer a desired specificity to immune effector T cells. As an HIV-1-specific CAR, CD4ζ CAR has been extensively tested in vitro as well as in clinical trials. T cells modified with this CAR mediated highly potent anti-HIV-1 activities in vitro and were well-tolerated in vivo, but exerted limited effects on viral load and reservoir size due to poor survival and/or functionality of the transduced cells in patients. We hypothesize that ectopic expression of CD4ζ on CD8+ T cells renders them susceptible to HIV-1 infection, resulting in poor survival of those cells. To test this possibility, highly purified CD8+ T cells were genetically modified with a CD4ζ-encoding lentiviral vector and infected with HIV-1. CD8+ T cells were vulnerable to HIV-1 infection upon expression of CD4ζ as evidenced by elevated levels of p24Gag in cells and culture supernatants. Concurrently, the number of CD4ζ-modified CD8+ T cells was reduced relative to control cells upon HIV-1 infection. To protect these cells from HIV-1 infection, we co-expressed two anti-HIV-1 shRNAs previously developed by our group together with CD4ζ. This combination vector was able to suppress HIV-1 infection without impairing HIV-1-dependent effector activities of CD4ζ. In addition, the number of CD4ζ-modified CD8+ T cells maintained similar levels to that of the control even under HIV-1 infection. These results suggest that protecting CD4ζ-modified CD8+ T cells from HIV-1 infection is required for prolonged HIV-1-specific immune surveillance. - Highlights: • Ectopic expression of CD4ζ CAR in CD8+ T cells renders them susceptible to HIV-1 infection. • Co-expression of two anti-HIV-1 shRNAs protects CD4ζ CAR-modified CD8+ T cells from HIV-1 infection. • Protecting CD4ζ CAR-modified CD8+ T cells from HIV-1 infection suppresses its cytopathic effect

  16. Alloreactive cloned T cell lines. I. Interactions between cloned amplifier and cytolytic T cell lines

    OpenAIRE

    1980-01-01

    Several T cell clones have been derived by limiting dilution of secondary mixed leukocyte culture cells stimulated by H-2- and M locus (Mls)-disparate spleen cells. When examined for the expression of cytolytic activity and the ability to proliferate, these cell clones can be classified into two major categories. One type of cell is noncytolytic; when cultured with irradiated spleen cells, such clones proliferate in response to Mls determinants. Some, but not all, of these clones express Lyt-...

  17. Epigallocatechin Gallate Attenuates Proliferation and Oxidative Stress in Human Vascular Smooth Muscle Cells Induced by Interleukin-1β via Heme Oxygenase-1

    Directory of Open Access Journals (Sweden)

    Po-Len Liu

    2014-01-01

    Full Text Available Proliferation of vascular smooth muscle cells (VSMCs triggered by inflammatory stimuli and oxidative stress contributes importantly to atherogenesis. The association of green tea consumption with cardiovascular protection has been well documented in epidemiological observations, however, the underlying mechanisms remain unclear. This study aimed to elucidate the effects of the most active green tea catechin derivative, (−-epigallocatechin-3-gallate (EGCG, in human aortic smooth muscle cells (HASMCs, focusing particularly on the role of a potent anti-inflammatory and antioxidative enzyme heme oxygenase-1 (HO-1. We found that pretreatment of EGCG dose- and time-dependently induced HO-1 protein levels in HASMCs. EGCG inhibited interleukin- (IL-1β-induced HASMC proliferation and oxidative stress in a dose-dependent manner. The HO-1 inducer CoPPIX decreased IL-1β-induced cell proliferation, whereas the HO-1 enzyme inhibitor ZnPPIX significantly reversed EGCG-caused growth inhibition in IL-1β-treated HASMCs. At the molecular level, EGCG treatment significantly activated nuclear factor erythroid-2-related factor (Nrf2 transcription activities. These results suggest that EGCG might serve as a complementary and alternative medicine in the treatment of these pathologies by inducing HO-1 expression and subsequently decreasing VSMC proliferation.

  18. Sialylation regulates peripheral tolerance in CD4+ T cells.

    Science.gov (United States)

    Brennan, Patrick J; Saouaf, Sandra J; Van Dyken, Steve; Marth, Jamey D; Li, Bin; Bhandoola, Avinash; Greene, Mark I

    2006-05-01

    Decreased binding by the 6C10 auto-antibody serves as a unique marker for CD4+ T cell unresponsiveness after the induction of T cell tolerance in Vbeta8.1 TCR transgenic mice. We further define the nature of the epitope recognized by the 6C10 antibody to be a subset of Thy-1 bearing incompletely sialylated N-linked glycans, and furthermore, we demonstrate that tolerant CD4+ T cells have an increased degree of cell-surface sialylation. To test the significance of the altered glycosylation state identified by the 6C10 auto-antibody in the tolerant CD4+ T cell population, surface sialic acid was cleaved enzymatically. Treatment of purified peripheral CD4+ T cells with Vibrio cholerae sialidase (VCS) leads to increased 6C10 binding, significantly enhances proliferation in the tolerant CD4+ population and corrects defects in phosphotyrosine signaling observed in the tolerant CD4+ T cell. Furthermore, in vivo administration of VCS enhances proliferation in both tolerant and naive CD4+ T cell subsets. These studies suggest that sialylation of glycoproteins on the surface of the CD4+ T cell contributes to the regulation of T cell responsiveness in the tolerant state. PMID:16291658

  19. Enhanced Proliferation of Porcine Bone Marrow Mesenchymal Stem Cells Induced by Extracellular Calcium is Associated with the Activation of the Calcium-Sensing Receptor and ERK Signaling Pathway

    Directory of Open Access Journals (Sweden)

    Jingjing Ye

    2016-01-01

    Full Text Available Porcine bone marrow mesenchymal stem cells (pBMSCs have the potential for application in regenerative medicine. This study aims to investigate the effects of extracellular calcium (Ca2+o on pBMSCs proliferation and to explore the possible underlying mechanisms. The results demonstrated that 4 mM Ca2+o significantly promoted pBMSCs proliferation by reducing the G0/G1 phase cell percentage and by increasing the S phase cell proportion and the proliferation index of pBMSCs. Accordingly, Ca2+o stimulated the expression levels of proliferative genes such as cyclin A2, cyclin D1/3, cyclin E2, and PCNA and inhibited the expression of p21. In addition, Ca2+o resulted in a significant elevation of intracellular calcium and an increased ratio of p-ERK/ERK. However, inhibition of calcium-sensing receptor (CaSR by its antagonist NPS2143 abolished the aforementioned effects of Ca2+o. Moreover, Ca2+o-induced promotion of pBMSCs proliferation, the changes of proliferative genes expression levels, and the activation of ERK1/2 signaling pathway were effectively blocked by U0126, a selective ERK kinase inhibitor. In conclusion, our findings provided evidence that the enhanced pBMSCs proliferation in response to Ca2+o was associated with the activation of CaSR and ERK1/2 signaling pathway, which may be useful for the application of pBMSCs in future clinical studies aimed at tissue regeneration and repair.

  20. Effect of ECM1 on the proliferation and cell cycle of HaCaT cell%细胞外基质蛋白1对HaCaT细胞增殖及细胞周期的影响

    Institute of Scientific and Technical Information of China (English)

    高志祥; 汪五清; 顾军

    2012-01-01

    Objective: To determine the effect of extracellular matrix proteins- 1 (ECM1) on the proliferation and cell cycle of HaCaT cell. Methods: the supernatant containing ECM1 of pEGFP - N2 - ECM1 transfected MCF - 7 cell was added to HaCaT cells. MTT method was used to detect the proliferation of HaCaT cells and FCM method was used to measure the change of cellular cycle. Results: ECM1 showed positive effect on the proliferation after 48hs, when treated with different concentration. Compared with control group, the cells in G, phase decreased, while cells in C2 and S phases increased. Conclusion: ECM1 can enhance the proliferation of HaCaT cell.%目的:确定细胞外基质蛋白1(ECM1)对HaCaT细胞增殖及细胞周期的影响.方法:将转染pEGFP- N2 - ECM1的含有ECM1的MCF-7细胞上清液作用于HaCaT细胞.MIT法检测HaCaT细胞的增殖,FCM法测定细胞周期变化.结果:与对照组相比,经ECM1作用48h后,细胞G1期比例显著降低,S期与G2期比例则显著升高.结论:ECM1对培养的HaCaT细胞具有诱导增殖的作用.

  1. Selective depletion of non-specific T cells as an early event in T cell response to bacterial and viral infections

    Institute of Scientific and Technical Information of China (English)

    JIANG Jiu

    2005-01-01

    @@ Early T cell depletion occurs prior to the development of an effective immune response to infections.Both antigen-specific and non-specific T cells are induced to express early activation markers soon after microbial infections.This is followed by massive depletion of non-specific T cells and extensive proliferation of antigen-specific T cells.Proliferating antigen-specific cells exhibit a broad spectrum of late activation markers while non-specific cells exhibit no sign of further activation before succumbing to apoptosis.These results have crucial implications for the understanding of early events in the development of a robust T cell response.

  2. Deletion of IL-4Ralpha on CD4 T cells renders BALB/c mice resistant to Leishmania major infection.

    Directory of Open Access Journals (Sweden)

    Magdalena Radwanska

    2007-05-01

    Full Text Available Effector responses induced by polarized CD4+ T helper 2 (Th2 cells drive nonhealing responses in BALB/c mice infected with Leishmania major. Th2 cytokines IL-4 and IL-13 are known susceptibility factors for L. major infection in BALB/c mice and induce their biological functions through a common receptor, the IL-4 receptor alpha chain (IL-4Ralpha. IL-4Ralpha-deficient BALB/c mice, however, remain susceptible to L. major infection, indicating that IL-4/IL-13 may induce protective responses. Therefore, the roles of polarized Th2 CD4+ T cells and IL-4/IL-13 responsiveness of non-CD4+ T cells in inducing non-healer or healer responses have yet to be elucidated. CD4+ T cell-specific IL-4Ralpha (Lck(creIL-4Ralpha(-/lox deficient BALB/c mice were generated and characterized to elucidate the importance of IL-4Ralpha signaling during cutaneous leishmaniasis in the absence of IL-4-responsive CD4+ T cells. Efficient deletion was confirmed by loss of IL-4Ralpha expression on CD4+ T cells and impaired IL-4-induced CD4+ T cell proliferation and Th2 differentiation. CD8+, gammadelta+, and NK-T cells expressed residual IL-4Ralpha, and representative non-T cell populations maintained IL-4/IL-13 responsiveness. In contrast to IL-4Ralpha(-/lox BALB/c mice, which developed ulcerating lesions following infection with L. major, Lck(creIL-4Ralpha(-/lox mice were resistant and showed protection to rechallenge, similar to healer C57BL/6 mice. Resistance to L. major in Lck(creIL-4Ralpha(-/lox mice correlated with reduced numbers of IL-10-secreting cells and early IL-12p35 mRNA induction, leading to increased delayed type hypersensitivity responses, interferon-gamma production, and elevated ratios of inducible nitric oxide synthase mRNA/parasite, similar to C57BL/6 mice. These data demonstrate that abrogation of IL-4 signaling in CD4+ T cells is required to transform non-healer BALB/c mice to a healer phenotype. Furthermore, a beneficial role for IL-4Ralpha signaling in L

  3. Homeostasis of T Cell Diversity

    Institute of Scientific and Technical Information of China (English)

    Vinay S. Mahajan; Ilya B. Leskov; Jianzhu Chen

    2005-01-01

    T cell homeostasis commonly refers to the maintenance of relatively stable T cell numbers in the peripheral lymphoid organs. Among the large numbers of T cells in the periphery, T cells exhibit structural diversity, I.e., the expression of a diverse repertoire of T cell receptors (TCRs), and functional diversity, I.e., the presence of T cells at na(I)ve, effector, and memory developmental stages. Although the homeostasis of T cell numbers has been extensively studied, investigation of the mechanisms underlying the maintenance of structural and functional diversity of T cells is still at an early stage. The fundamental feature throughout T cell development is the interaction between the TCR and either self or foreign peptides in association with MHC molecules. In this review, we present evidence showing that homeostasis of T cell number and diversity is mediated through competition for limiting resources.The number of T cells is maintained through competition for limiting cytokines, whereas the diversity of T cells is maintained by competition for self-peptide-MHC complexes. In other words, diversity of the self-peptide repertoire limits the structural (TCR) diversity of a T cell population. We speculate that cognate low affinity self-peptides,acting as weak agonists and antagonists, regulate the homeostasis of T cell diversity whereas non-cognate or null peptides which are extremely abundant for any given TCR, may contribute to the homeostasis of T cell number by providing survival signals. Moreover, self-peptides and cytokines may form specialized niches for the regulation of T cell homeostasis.

  4. Homeostasis of T Cell Diversity

    Institute of Scientific and Technical Information of China (English)

    VinayS.Mahajan; IlyaB.Leskov; JianzhuChen

    2005-01-01

    T cell homeostasis commonly refers to the maintenance of relatively stable T cell numbers in the peripheral lymphoid organs. Among the large numbers of T cells in the periphery, T cells exhibit structural diversity, i.e., the expression of a diverse repertoire of T cell receptors (TCRs), and functional diversity, i.e., the presence of T cells at naive, effector, and memory developmental stages. Although the homeostasis of T cell numbers has been extensively studied, investigation of the mechanisms underlying the maintenance of structural and functional diversity of T cells is still at an early stage. The fundamental feature throughout T cell development is the interaction between the TCR and either self or foreign peptides in association with MHC molecules. In this review, we present evidence showing that homeostasis of T cell number and diversity is mediated through competition for limiting resources. The number of T cells is maintained through competition for limiting cytokines, whereas the diversity of T cells is maintained by competition for self-peptide-MHC complexes. In other words, diversity of the self-peptide repertoire limits the structural (TCR) diversity of a T cell population. We speculate that cognate low affinity self-peptides, acting as weak agonists and antagonists, regulate the homeostasis of T cell diversity whereas non-cognate or null peptides which are extremely abundant for any given TCR, may contribute to the homeostasis of T cell number by providing survival signals. Moreover, self-peptides and cytokines may form specialized niches for the regulation of T cell homeostasis. Cellular & Molecular Immunology. 2005;2(1): 1-10.

  5. Isolation and Characterization of Salmonid CD4+ T Cells.

    Science.gov (United States)

    Maisey, Kevin; Montero, Ruth; Corripio-Miyar, Yolanda; Toro-Ascuy, Daniela; Valenzuela, Beatriz; Reyes-Cerpa, Sebastián; Sandino, Ana María; Zou, Jun; Wang, Tiehui; Secombes, Christopher J; Imarai, Mónica

    2016-05-15

    This study reports the isolation and functional characterization of rainbow trout (Oncorhynchus mykiss) CD4-1(+) T cells and the establishment of an IL-15-dependent CD4-1(+) T cell line. By using Abs specific for CD4-1 and CD3ε it was possible to isolate the double-positive T cells in spleen and head kidney. The morphology and the presence of transcripts for T cell markers in the sorted CD4-1(+)CD3ε(+) cells were studied next. Cells were found to express TCRα, TCRβ, CD152 (CTLA-4), CD154 (CD40L), T-bet, GATA-3, and STAT-1. The sorted CD4-1(+) T cells also had a distinctive functional attribute of mammalian T lymphocytes, namely they could undergo Ag-specific proliferation, using OVA as a model Ag. The OVA-stimulated cells showed increased expression of several cytokines, including IFN-γ1, IL-4/13A, IL-15, IL-17D, IL-10, and TGF-β1, perhaps indicating that T cell proliferation led to differentiation into distinct effector phenotypes. Using IL-15 as a growth factor, we have selected a lymphoid cell line derived from rainbow trout head kidney cells. The morphology, cell surface expression of CD4-1, and the presence of transcripts of T cell cytokines and transcription factors indicated that this is a CD4-1(+) T cell line. To our knowledge, this is the first demonstration of the presence of CD4-1(+)CD3ε(+) T cells in salmonids. As in mammals, CD4-1(+) T cells may be the master regulators of immune responses in fish, and therefore these findings and the new model T cell line developed will contribute to a greater understanding of T cell function and immune responses in teleost fish. PMID:27053758

  6. Cryptotanshinone induces inhibition of breast tumor growth by cytotoxic CD4+ T cells through the JAK2/STAT4/ perforin pathway.

    Science.gov (United States)

    Zhou, Jun; Xu, Xiao-Zhen; Hu, Yao-Ren; Hu, Ai-Rong; Zhu, Cheng-Liang; Gao, Guo-Sheng

    2014-01-01

    Cryptotanshinone (CPT), is a quinoid diterpene isolated from the root of the Asian medicinal plant, Salvia miotiorrhiza bunge. Numerous researchers have found that it could work as a potent antitumor agent to inhibit tumor growth in vitro, buith there has been much less emphasis on its in vivo role against breast tumors. Using a mouse tumor model of MCF7 cells, we showed that CPT strongly inhibited MCF7 cell growth in vivo with polarization of immune reactions toward Th1-type responses, stimulation of naive CD4+ T cell proliferation, and also increased IFN-γ and perforin production of CD4+ T cells in response to tumor-activated splenocytes. Furthermore, data revealed that the cytotoxic activity of CD4+ T cells induced by CPT was markedly abrogated by concanamycin A(CMA), a perforin inhibitor, but not IFN-γ Ab. On the other hand, after depletion of CD4+ T cells or blocked perforin with CMA in a tumor-bearing model, CPT could not effectively suppress tumor growth, but this phenomenon could be reversed by injecting naive CD4+ T cells. Thus, our results suggested that CPT mainly inhibited breast tumor growth through inducing cytotoxic CD4+ T cells to secrete perforin. We further found that CPT enhanced perforin production of CD4+ T cells by up-regulating JAK2 and STAT4 phosphorylation. These findings suggest a novel potential therapeutic role for CPT in tumor therapy, and demonstrate that CPT performs its antitumor functions through cytotoxic CD4+ T cells.

  7. Role of isothiocyanate conjugate of pterostilbene on the inhibition of MCF-7 cell proliferation and tumor growth in Ehrlich ascitic cell induced tumor bearing mice

    Energy Technology Data Exchange (ETDEWEB)

    Nikhil, Kumar; Sharan, Shruti; Chakraborty, Ajanta [Molecular Endocrinology Laboratory, Department of Biotechnology, Indian Institute of Technology Roorkee, Roorkee 247 667, Uttarakhand (India); Bodipati, Naganjaneyulu; Krishna Peddinti, Rama [Department of Chemistry, Indian Institute of Technology Roorkee, Roorkee 247 667, Uttarakhand (India); Roy, Partha, E-mail: paroyfbs@iitr.ernet.in [Molecular Endocrinology Laboratory, Department of Biotechnology, Indian Institute of Technology Roorkee, Roorkee 247 667, Uttarakhand (India)

    2014-01-15

    Naturally occurring pterostilbene (PTER) and isothiocyanate (ITC) attract great attention due to their wide range of biological properties, including anti-cancer, anti-leukemic, anti-bacterial and anti-inflammatory activities. A novel class of hybrid compound synthesized by introducing an ITC moiety on PTER backbone was evaluated for its anti-cancer efficacy in hormone-dependent breast cancer cell line (MCF-7) in vitro and Ehrlich ascitic tumor bearing mice model in vivo. The novel hybrid molecule showed significant in vitro anti-cancer activity (IC{sub 50}=25±0.38) when compared to reference compound PTER (IC{sub 50}=65±0.42). The conjugate molecule induced both S and G2/M phase cell cycle arrest as indicated by flow cytometry analysis. In addition, the conjugate induced cell death was characterized by changes in cell morphology, DNA fragmentation, activation of caspase-9, release of cytochrome-c into cytosol and increased Bax: Bcl-2 ratio. The conjugate also suppressed the phosphorylation of Akt and ERK. The conjugate induced cell death was significantly increased in presence of A6730 (a potent Akt1/2 kinase inhibitor) and PD98059 (a specific ERK inhibitor). Moreover, the conjugated PTER inhibited tumor growth in Ehrlich ascitic cell induced tumor bearing mice as observed by reduction in tumor volume compared to untreated animals. Collectively, the pro-apoptotic effect of conjugate is mediated through the activation of caspases, and is correlated with the blockade of the Akt and ERK signaling pathways in MCF-7 cells. - Highlights: • Conjugate was prepared by appending isothiocyanate moiety on pterostilbene backbone. • Conjugate showed anticancer effects at comparatively lower dose than pterostilbene. • Conjugate caused blockage of the Akt and ERK signaling pathways in MCF-7 cells. • Conjugate significantly reduced solid tumor volume as compared to pterostilbene.

  8. The self-antigen, thyroglobulin, induces antigen-experienced CD4+ T cells from healthy donors to proliferate and promote production of the regulatory cytokine, interleukin-10, by monocytes

    DEFF Research Database (Denmark)

    Nielsen, Claus H; Galdiers, Marcel P; Hedegaard, Chris J;

    2010-01-01

    monocytes were prime producers of IL-10 in the early TG response, a few IL-10-secreting CD4(+) T cells, primarily with CD45RO(+) memory phenotype, were also detected. Furthermore, T-cell depletion from the mononuclear cell preparation abrogated monocyte IL-10 production. Our findings indicate active....... Whereas TT induced pro-inflammatory cytokines [interleukin-2 (IL-2)/interferon-gamma (IFN-gamma)/IL-4/IL-5], TG evoked persistent release of the regulatory IL-10. Some donors, however, also responded with late IFN-gamma production, suggesting that the regulation by IL-10 could be overridden. Although...

  9. Proliferation and Apoptosis of Bone Marrow CD4~+ T Cells in Patients with Aplastic Anemia and Impacts of the Secreted Cytokines on Hematopoietic Stem Cells from Umbilical Cord Blood

    Institute of Scientific and Technical Information of China (English)

    郑邈; 孙汉英; 周剑峰; 徐慧珍; 黄丽芳; 刘文励

    2010-01-01

    Recent studies indicate that immune-associated aplastic anemia(AA)resembles such autoimmune diseases as insulin-dependent diabetes and chronic autoimmune thyroiditis that belong to organ-specific autoimmune diseases.Many independent investigation groups have successfully isolated the pathopoiesis-associated T cell clone causing hematopoiesis failure with a CD4 phenotype from peripheral blood and bone marrow(BM)in AA patients.In the current study,BM CD4+ T cells were isolated from AA patients and healthy con...

  10. T cell subpopulations.

    Science.gov (United States)

    Romagnani, Sergio

    2014-01-01

    The role of allergen-specific CD4+ effector type 2 helper (Th2) cells in the pathogenesis of allergic disorders is an established fact. Th2 cells produce interleukin (IL)-4 and IL-13, which induce immunoglobulin E production by B cells, and IL-5 that allows recruitment of eosinophils. Two main mechanisms control the Th2-mediated allergic inflammation: immune deviation (or Th1 redirection) and immune regulation. Regulatory T (Treg) cells exhibit a CD4+ phenotype and include Foxp3-positive thymic and induced Tregs, as well as Foxp3-negative IL-10-producing cells. Both immune deviation and immune regulation evoked by the maternal and newborn microbial environment probably operate in preventing allergen-specific Th2 responses. However, microbe-related protection from allergy seems to mainly depend on epigenetically controlled acetylation of the IFNG promoter of CD4+ T cells. Even Th17 and Th9 cells, as well as invariant NKT cells, have been implicated in the pathogenesis of allergic disorders, but their role is certainly more limited. Recently, innate lymphoid type 2 cells (ILC2) have been found to be able to produce high amounts of IL-5 and IL-13 in response to stimulation with IL-25 and IL-33 produced by non-immune cells. Together with Th2 cells, ILC2 may contribute to the induction and maintenance of allergic inflammation. PMID:24925396

  11. Production of antigen-specific suppressive T cell factor by radiation leukemia virus-transformed suppressor T cells.

    OpenAIRE

    Ricciardi-Castagnoli, P; Doria, G; Adorini, L

    1981-01-01

    Hen egg-white lysozyme (HEL)-specific suppressor T cells induced in C57BL/6 mice have been selected by sequential passage over plates coated with goat anti-mouse Ig and HEL. These suppressor T cells, 80% I-J+, were infected in vitro with radiation leukemia virus (RadLV/Nu1) and injected intravenously into sublethally irradiated syngeneic recipients. After 4-6 months, 6 out of 20 injected mice developed thymic lymphomas, which were maintained by transplantation into histocompatible hosts and s...

  12. Intravenous grafts of amniotic fluid-derived stem cells induce endogenous cell proliferation and attenuate behavioral deficits in ischemic stroke rats.

    Directory of Open Access Journals (Sweden)

    Naoki Tajiri

    Full Text Available We recently reported isolation of viable rat amniotic fluid-derived stem (AFS cells [1]. Here, we tested the therapeutic benefits of AFS cells in a rodent model of ischemic stroke. Adult male Sprague-Dawley rats received a 60-minute middle cerebral artery occlusion (MCAo. Thirty-five days later, animals exhibiting significant motor deficits received intravenous transplants of rat AFS cells or vehicle. At days 60-63 post-MCAo, significant recovery of motor and cognitive function was seen in stroke animals transplanted with AFS cells compared to vehicle-infused stroke animals. Infarct volume, as revealed by hematoxylin and eosin (H&E staining, was significantly reduced, coupled with significant increments in the cell proliferation marker, Ki67, and the neuronal marker, MAP2, in the dentate gyrus (DG [2] and the subventricular zone (SVZ of AFS cell-transplanted stroke animals compared to vehicle-infused stroke animals. A significantly higher number of double-labeled Ki67/MAP2-positive cells and a similar trend towards increased Ki67/MAP2 double-labeling were observed in the DG and SVZ of AFS cell-transplanted stroke animals, respectively, compared to vehicle-infused stroke animals. This study reports the therapeutic potential of AFS cell transplantation in stroke animals, possibly via enhancement of endogenous repair mechanisms.

  13. Human Vδ2+ γδ T cells differentially induce maturation, cytokine production and alloreactive T cell stimulation by dendritic cells and B cells

    OpenAIRE

    Andreea ePetrasca; Doherty, Derek G.

    2014-01-01

    Human γδ T cells expressing the Vγ9Vδ2 T cell receptor can induce maturation of dendritic (DC) into antigen-presenting cells (APC) and B cells into antibody-secreting plasma cells. Since B cells are capable of presenting antigens to T cells, we investigated if Vγ9Vδ2 T cells can influence antigen presentation by these cells. We report that Vδ2 T cells induced expression of CD86, HLA-DR and CD40 by B cells and stimulated the release of IL-4, IL-6, TNF-α, and IgG, IgA and IgM. Vγ9Vδ2 T cells al...

  14. Metabolic regulation of regulatory T cell development and function

    Directory of Open Access Journals (Sweden)

    David John Coe

    2014-11-01

    Full Text Available It is now well established that the effector T cell (Teff response is regulated by a series of metabolic switches. Quiescent T cells predominantly require ATP-generating processes, whereas proliferating Teff require high metabolic flux through growth-promoting pathways, such as glycolysis. Pathways that control metabolism and immune cell function are intimately linked, and changes in cell metabolism at both the cell and system levels have been shown to enhance or suppress specific T cell effector functions. Furthermore, functionally distinct T cell subsets have been shown to require distinct energetic and biosynthetic pathways to support their specific functional needs. In particular, naturally occurring regulatory T cells (Treg are characterized by a unique metabolic signature distinct to that of conventional Teff cells. We here briefly review the signaling pathways that control Treg metabolism and how this metabolic phenotype integrates their differentiation and function. Ultimately, these metabolic features may provide new opportunities for the therapeutic modulation of unwanted immune responses.

  15. CRTAM is negatively regulated by ZEB1 in T cells.

    Science.gov (United States)

    Rojas-Marquez, C; Valle-Rios, R; Lopez-Bayghen, E; Ortiz-Navarrete, V

    2015-08-01

    T cell activation leads to the induction of genes that are required for appropriate immune responses. This includes CRTAM (Class-I MHC-restricted T cell associated molecule), a protein that plays a key role in T cell development, proliferation, and generating cell polarity during activation. We previously characterized the CRTAM promoter and described how AP-1 family members are important for inducing CRTAM expression upon antigenic activation. Here, we show that CRTAM is a molecular target for ZEB1 (zinc finger E-box-binding protein), a homeodomain/Zn finger transcription factor. Overexpression of ZEB1 repressed CRTAM promoter activity, as well as endogenous CRTAM levels in human T cells. ZEB1-mediated transcriptional repression was abolished when E-box-like elements in the CRTAM promoter are mutated. In summary, ZEB1 functions as a transcriptional repressor for the CRTAM gene in both non-stimulated and stimulated T cells, thereby modulating adaptive immune responses.

  16. Mechanism of T cell regulation by microRNAs

    International Nuclear Information System (INIS)

    MicroRNAs (miRNAs) are small, non-coding single-stranded RNAs that can modulate target gene expression at post-transcriptional level and participate in cell proliferation, differentiation, and apoptosis. T cells have important functions in acquired immune response; miRNAs regulate this immune response by targeting the mRNAs of genes involved in T cell development, proliferation, differentiation, and function. For instance, miR-181 family members function in progression by targeting Bcl2 and CD69, among others. MiR-17 to miR-92 clusters function by binding to CREB1, PTEN, and Bim. Considering that the suppression of T cell-mediated immune responses against tumor cells is involved in cancer progression, we should investigate the mechanism by which miRNA regulates T cells to develop new approaches for cancer treatment

  17. 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.

  18. Qualitative and quantitative analysis of adenovirus type 5 vector-induced memory CD8 T cells: not as bad as their reputation.

    Science.gov (United States)

    Steffensen, Maria Abildgaard; Holst, Peter Johannes; Steengaard, Sanne Skovvang; Jensen, Benjamin Anderschou Holbech; Bartholdy, Christina; Stryhn, Anette; Christensen, Jan Pravsgaard; Thomsen, Allan Randrup

    2013-06-01

    It has been reported that adenovirus (Ad)-primed CD8 T cells may display a distinct and partially exhausted phenotype. Given the practical implications of this claim, we decided to analyze in detail the quality of Ad-primed CD8 T cells by directly comparing these cells to CD8 T cells induced through infection with lymphocytic choriomeningitis virus (LCMV). We found that localized immunization with intermediate doses of Ad vector induces a moderate number of functional CD8 T cells which qualitatively match those found in LCMV-infected mice. The numbers of these cells may be efficiently increased by additional adenoviral boosting, and, importantly, the generated secondary memory cells cannot be qualitatively differentiated from those induced by primary infection with replicating virus. Quantitatively, DNA priming prior to Ad vaccination led to even higher numbers of memory cells. In this case, the vaccination led to the generation of a population of memory cells characterized by relatively low CD27 expression and high CD127 and killer cell lectin-like receptor subfamily G member 1 (KLRG1) expression. These memory CD8 T cells were capable of proliferating in response to viral challenge and protecting against infection with live virus. Furthermore, viral challenge was followed by sustained expansion of the memory CD8 T-cell population, and the generated memory cells did not appear to have been driven toward exhaustive differentiation. Based on these findings, we suggest that adenovirus-based prime-boost regimens (including Ad serotype 5 [Ad5] and Ad5-like vectors) represent an effective means to induce a substantially expanded, long-lived population of high-quality transgene-specific memory CD8 T cells.

  19. T-cell-predominant lymphoid hyperplasia in a tattoo*

    OpenAIRE

    Souza, Erica Sales; Rocha, Bruno de Oliveira; Batista, Everton da Silva; de Oliveira, Rodrigo Ferreira; Farre, Lourdes; Bittencourt, Achilea Lisboa

    2014-01-01

    Cutaneous lymphoid hyperplasia (CLH) can be idiopathic or secondary to external stimuli, and is considered rare in tattoos. The infiltrate can be predominantly of B or T-cells, the latter being seldom reported in tattoos. We present a case of a predominantly T CLH, secondary to the black pigment of tattooing in a 35-year-old patient, with a dense infiltrate of small, medium and scarce large T-cells. Analysis of the rearrangement of T-cells receptor revealed a polyclonal proliferation. Since t...

  20. Self-reactive T cells

    DEFF Research Database (Denmark)

    Becker, Jürgen C; thor Straten, Per; Andersen, Mads Hald

    2014-01-01

    -proteins expressed in regulatory immune cells have been reported, especially in patients with cancer. The seemingly lack of tolerance toward such proteins is interesting, as it suggests a regulatory function of self-reactive T (srT) cells, which may be important for the fine tuning of the immune system....... In particular, surprising has been the description of cytotoxic srT cells that are able to eliminate normal regulatory immune cells. Such srT cells may be important as effector cells that suppress regulatory suppressor cells. The current knowledge of the nature and function of srT cells is still limited. Still......, the therapeutic targeting of srT cells offers a novel approach to harness immune-regulatory networks in cancer....

  1. 苯扎贝特对原发性胆汁性肝硬化患者外周血CD4+T细胞的抑制作用研究%Suppressive effects of bezafibrate on proliferation and cytokine production by CD4+T cells from patients with primary biliary cirrhosis

    Institute of Scientific and Technical Information of China (English)

    陈曲波; 彭桉平; 黎翠翠; 赵蓉; 卢欣沂; 何敏; 周丽敏; 吴炜霖

    2014-01-01

    Objective:To investigate the effects of bezafibrate (BF) on the activation,proliferation and differentiation of CD4+T cells from primary biliary cirrhosis ( PBC) patients and to elucidate the mechanisms for the immunosuppressive effects of BF and to further provide experience basis for BF target therapy PBC.Methods:PBMCs were isolated from PBC patients then CD 4+T cells were selected by MACS, and stimulated with anti-CD3, anti-CD28, in the presence of different concentration of BF.The cytokines were measured by ELISA,and the activation,proliferation and differentiation of CD4+T cells were analyzed by flow cytometry.Results:(1) BF could inhibit the activation of CD 4+T cells in PBC patients.(2) BF could inhibit the proliferation of CD 4+T cells in PBC patients in a dose-dependent manner (P<0.05).(3)BF could down-regulation IFN-γand IL-17 production of CD4+T cells in a dose-dependent manner ( P<0.05 ).Conclusion: BF could inhibit immune responses of PBC patients by suppressing CD 4+T cells activation;proliferation and cytokine production.%目的:观察苯扎贝特(Bezafibrate,BF)对原发性胆汁性肝硬化(Primary biliary cirrhosis,PBC)患者外周血CD4+T细胞活化增殖和分化的影响,探讨其免疫抑制作用机理,为BF治疗PBC的作用靶点提供实验依据。方法:分离PBC患者的PBMCs,磁珠分选CD4+T细胞,加入anti-CD3、anti-CD28及不同浓度的BF,以流式细胞方法和ELISA分析BF对CD4+T细胞活化、增殖及Th1/Th17细胞因子产生的影响。结果:(1)BF能抑制PBC患者外周血CD4+T细胞活化;(2)BF呈浓度依赖性抑制PBC外周血CD4+T细胞增殖(P<0.05);(3)BF也能够抑制PBC患者外周血CD4+T细胞产生IFN-γ和IL-17(P<0.05)。结论:BF可通过抑制CD4+T细胞活化增殖及细胞因子分泌,发挥免疫抑制作用。

  2. Oligomeric Procyanidins Interfere with Glycolysis of Activated T Cells. A Novel Mechanism for Inhibition of T Cell Function

    Directory of Open Access Journals (Sweden)

    Masao Goto

    2015-10-01

    Full Text Available Procyanidins, which are flavonoids that are found in a variety of plant species, reduce or prevent immune disorders, such as allergy and autoimmune diseases, through an unknown mechanism. In the present study, we investigated the effects of procyanidins on the T cell receptor (TCR-mediated responses of CD4+ T cells in vitro. Apple procyanidins strongly suppressed the proliferation of splenic CD4+ T cells that were stimulated by an anti-CD3ε antibody, as well as splenocytes stimulated by antigen, but did not alter interleukin (IL-2 secretion from these cells. Furthermore, we found that oligomeric procyanidins strongly suppressed, in a degree of polymerization dependent manner, the proliferation of activated CD4+ T cells, as well as their production of effector cytokines, including glycolysis associated-cytokines, without affecting IL-2 secretion. Additionally, we investigated the inhibitory effects of oligomeric procyanidins on the glycolytic activity of activated CD4+ T cells. We show that pentameric procyanidin suppressed L-lactate production and glucose uptake in activated CD4+ T cells. These results suggest that oligomeric procyanidins suppress the functions of activated CD4+ T cells by interfering with glycolysis.

  3. Regulatory T cells prevent CD8 T cell maturation by inhibiting CD4 Th cells at tumor sites.

    Science.gov (United States)

    Chaput, Nathalie; Darrasse-Jèze, Guillaume; Bergot, Anne-Sophie; Cordier, Corinne; Ngo-Abdalla, Stacie; Klatzmann, David; Azogui, Orly

    2007-10-15

    Natural regulatory T cells (Tregs) are present in high frequencies among tumor-infiltrating lymphocytes and in draining lymph nodes, supposedly facilitating tumor development. To investigate their role in controlling local immune responses, we analyzed intratumoral T cell accumulation and function in the presence or absence of Tregs. Tumors that grew in normal BALB/c mice injected with the 4T1 tumor cell line were highly infiltrated by Tregs, CD4 and CD8 cells, all having unique characteristics. Most infiltrating Tregs expressed low levels of CD25Rs and Foxp3. They did not proliferate even in the presence of IL-2 but maintained a strong suppressor activity. CD4 T cells were profoundly anergic and CD8 T cell proliferation and cytotoxicity were severely impaired. Depletion of Tregs modified the characteristics of tumor infiltrates. Tumors were initially invaded by activated CD4(+)CD25(-) T cells, which produced IL-2 and IFN-gamma. This was followed by the recruitment of highly cytotoxic CD8(+) T cells at tumor sites leading to tumor rejection. The beneficial effect of Treg depletion in tumor regression was abrogated when CD4 helper cells were also depleted. These findings indicate that the massive infiltration of tumors by Tregs prevents the development of a successful helper response. The Tregs in our model prevent Th cell activation and subsequent development of efficient CD8 T cell activity required for the control of tumor growth. PMID:17911581

  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. Redox Regulation of T-Cell Function: From Molecular Mechanisms to Significance in Human Health and Disease

    OpenAIRE

    Kesarwani, Pravin; Murali, Anuradha K.; Al-Khami, Amir A.; Mehrotra, Shikhar

    2013-01-01

    Reactive oxygen species (ROS) are thought to have effects on T-cell function and proliferation. Low concentrations of ROS in T cells are a prerequisite for cell survival, and increased ROS accumulation can lead to apoptosis/necrosis. The cellular redox state of a T cell can also affect T-cell receptor signaling, skewing the immune response. Various T-cell subsets have different redox statuses, and this differential ROS susceptibility could modulate the outcome of an immune response in various...

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

    Directory of Open Access Journals (Sweden)

    Hui Xu

    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.

  7. Effect of melatonin on CD4+ T cell proliferation and the activity of Foxp3 promoter in mice%褪黑素对小鼠CD4+T细胞增殖及Foxp3启动子活性的影响

    Institute of Scientific and Technical Information of China (English)

    刘卉; 徐丽; 王日雄; 张慧; 周瑞祥

    2012-01-01

    目的 探讨褪黑素(melatonin,MLT)对小鼠CD4+T细胞增殖及Foxp3 (Forkhead box P3)启动子活性的影响,进一步丰富神经内分泌免疫网络学说.方法 免疫磁珠分选小鼠脾CD4+T细胞,CCK-8法检测褪黑素对其增殖活性的影响;构建、筛选及鉴定Foxp3核心和全长启动子重组载体,并且电转染入小鼠CD4+T细胞,加以不同淋巴细胞刺激因子和褪黑素干预,用双荧光素酶报告基因法检测Foxp3启动子的活性变化.结果 与空白对照组相比,从10-5 mol浓度的MLT开始对CD4+T细胞有毒性作用,并呈剂量依赖性.10-6 mol MLT对CD4+T细胞的增殖活性无影响.3种淋巴细胞刺激因子(佛波酯PMA+离子霉素ionomycin;植物血凝素PHA;T细胞抗原受体TCR)刺激和(或)褪黑素干预虽然使小鼠Foxp3核心或全长启动子活性有所上调,但与空白对照差异无统计学意义(P>0.05).结论 不同浓度褪黑素对小鼠CD4+T细胞增殖活性产生不同影响;褪黑素未显著增强小鼠Foxp3启动子活性.%Objective To investigate the effect of melatonin on CD4+T cell proliferation and promoter activity of Foxp3 in mice, which further enrich the theory of neuroendocrine-immune network. Methods Purified CD4+T cells were isolated from spleen using magnetic beads for the negative selection process. The effect of melatonin on CD4+ T cell proliferation by using CCK-8 method. Construction and identification of reeombinant plasmids of the core and full length for Foxp3 promoter, which electroporated into CD4+T cells using the Nucleofector. Then the cells stimulated with different kinds of lymphatic stimulatory substances and intervented by melatonin. Finally, luciferase activity was measured by the dual luciferase assay system. Results Compared with the blank control, from 10-5 mol concentration of MLT begin to be poisonous for CD4+ T cell, which exhibited a dose dependent. And 10-6 mol concentration of MLT has no effect on cell proliferation. Three kinds

  8. Genetic Modification of T Cells

    Directory of Open Access Journals (Sweden)

    Richard A. Morgan

    2016-04-01

    Full Text Available Gene transfer technology and its application to human gene therapy greatly expanded in the last decade. One area of investigation that appears particularly promising is the transfer of new genetic material into T cells for the potential treatment of cancer. Herein, we describe several core technologies that now yield high-efficiency gene transfer into primary human T cells. These gene transfer techniques include viral-based gene transfer methods based on modified Retroviridae and non-viral methods such as DNA-based transposons and direct transfer of mRNA by electroporation. Where specific examples are cited, we emphasize the transfer of chimeric antigen receptors (CARs to T cells, which permits engineered T cells to recognize potential tumor antigens.

  9. B and T cell screen

    Science.gov (United States)

    Direct immunofluorescence; E-rosetting; T and B lymphocyte assays; B and T lymphocyte assays ... identifiers are added to distinguish between T and B cells. The E-rosetting test identifies T cells ...

  10. ADULT T CELL LEUKEMIA LYMPHOMA

    OpenAIRE

    Neely, S. M.

    2004-01-01

    Adult T cell leukemia lymphoma (ATLL) is a CD4+ lymphoproliferative malignancy resulting from human T-cell leukemia virus type 1 (HTLV1) infection. It includes differing clinical forms classified as smoldering, chronic, lymphomatous, and acute ATLL. The Tax protein of HTLV-1 has been implicated as a viral oncoprotein which enhances virus replication and alters cellular gene expression, including activation of nuclear factor kappa B (NF kB), to result in lymphoid transformation. Chemotherapy f...

  11. The protein pheromone Er-1 of the ciliate Euplotes raikovi stimulates human T-cell activity: Involvement of interleukin-2 system

    International Nuclear Information System (INIS)

    Water-soluble protein signals (pheromones) of the ciliate Euplotes have been supposed to be functional precursors of growth factors and cytokines that regulate cell–cell interaction in multi-cellular eukaryotes. This work provides evidence that native preparations of the Euplotes raikovi pheromone Er-1 (a helical protein of 40 amino acids) specifically increases viability, DNA synthesis, proliferation, and the production of interferon-γ, tumor necrosis factor-α, interleukin (IL)-1β, IL-2, and IL-13 in human Jurkat T-cells. Also, Er-1 significantly decreases the mRNA levels of the β and γ subunits of IL-2 receptor (IL-2R), while the mRNA levels of the α subunit appeared to be not affected. Jurkat T-cell treatments with Er-1 induced the down-regulation of the IL-2Rα subunit by a reversible and time-dependent endocytosis, and increased the levels of phosphorylation of the extracellular signal-regulated kinases (ERK). The cell-type specificity of these effects was supported by the finding that Er-1, although unable to directly influence the growth of human glioma U-373 cells, induced Jurkat cells to synthesize and release factors that, in turn, inhibited the U-373 cell proliferation. Overall, these findings imply that Er-1 coupling to IL-2R and ERK immuno-enhances T-cell activity, and that this effect likely translates to an inhibition of glioma cell growth. -- Highlights: ► Euplotes pheromone Er-1 increases the growth of human Jurkat T-cells. ► Er-1 increases the T-cell production of specific cytokines. ► Er-1 activates interleukin-2 receptor and extracellular signal-regulated kinases. ► The immuno-enhancing effect of Er-1 on Jurkat cells translates to an inhibition of human glioma cell growth.

  12. The protein pheromone Er-1 of the ciliate Euplotes raikovi stimulates human T-cell activity: Involvement of interleukin-2 system

    Energy Technology Data Exchange (ETDEWEB)

    Cervia, Davide, E-mail: d.cervia@unitus.it [Department for Innovation in Biological, Agro-food and Forest systems (DIBAF), University of Tuscia, Viterbo (Italy); Department of Biomedical and Clinical Sciences, “Luigi Sacco” University Hospital, University of Milan, Milano (Italy); Catalani, Elisabetta; Belardinelli, Maria Cristina [Department for Innovation in Biological, Agro-food and Forest systems (DIBAF), University of Tuscia, Viterbo (Italy); Perrotta, Cristiana [Department of Biomedical and Clinical Sciences, “Luigi Sacco” University Hospital, University of Milan, Milano (Italy); Picchietti, Simona [Department for Innovation in Biological, Agro-food and Forest systems (DIBAF), University of Tuscia, Viterbo (Italy); Alimenti, Claudio [Department of Environmental and Natural Sciences, University of Camerino, Camerino (Italy); Casini, Giovanni; Fausto, Anna Maria [Department for Innovation in Biological, Agro-food and Forest systems (DIBAF), University of Tuscia, Viterbo (Italy); Vallesi, Adriana [Department of Environmental and Natural Sciences, University of Camerino, Camerino (Italy)

    2013-02-01

    Water-soluble protein signals (pheromones) of the ciliate Euplotes have been supposed to be functional precursors of growth factors and cytokines that regulate cell–cell interaction in multi-cellular eukaryotes. This work provides evidence that native preparations of the Euplotes raikovi pheromone Er-1 (a helical protein of 40 amino acids) specifically increases viability, DNA synthesis, proliferation, and the production of interferon-γ, tumor necrosis factor-α, interleukin (IL)-1β, IL-2, and IL-13 in human Jurkat T-cells. Also, Er-1 significantly decreases the mRNA levels of the β and γ subunits of IL-2 receptor (IL-2R), while the mRNA levels of the α subunit appeared to be not affected. Jurkat T-cell treatments with Er-1 induced the down-regulation of the IL-2Rα subunit by a reversible and time-dependent endocytosis, and increased the levels of phosphorylation of the extracellular signal-regulated kinases (ERK). The cell-type specificity of these effects was supported by the finding that Er-1, although unable to directly influence the growth of human glioma U-373 cells, induced Jurkat cells to synthesize and release factors that, in turn, inhibited the U-373 cell proliferation. Overall, these findings imply that Er-1 coupling to IL-2R and ERK immuno-enhances T-cell activity, and that this effect likely translates to an inhibition of glioma cell growth. -- Highlights: ► Euplotes pheromone Er-1 increases the growth of human Jurkat T-cells. ► Er-1 increases the T-cell production of specific cytokines. ► Er-1 activates interleukin-2 receptor and extracellular signal-regulated kinases. ► The immuno-enhancing effect of Er-1 on Jurkat cells translates to an inhibition of human glioma cell growth.

  13. CD4 + CD25 + regulatory T cells-induced tolerance of islet transplantation by targeting OX40/ OX40L costimulation pathway%靶向OX40/OX40L通路对CD4+CD25+调节性T细胞诱导移植耐受的影响

    Institute of Scientific and Technical Information of China (English)

    陈恕求; 许斌; 任全; 王奕铎; 王旭辉; 李宪昌; 陈明

    2012-01-01

    目的 观察OX40/OX40L共刺激通路在调节性T细胞(Treg)诱导移植耐受中的作用.方法 建立小鼠胰岛移植模型,分3组:IgG组、抗-OX40L单抗(RM134L)+抗-CD154单抗( MR1)组、联合RM134L+ MR1及抗-CD25单抗(PC61)组.存活超过150 d小鼠切除移植侧肾脏,在对侧行同或不同主要组织相容性复合体( MHC)的2次胰岛移植.观察各组平均存活时间(MST).检测效应性T细胞(Teff)、野生型和CD154敲除小鼠Treg OX40表达.检测同基因小鼠胰岛、胰岛移植不加或加RM134L+ MR1治疗的移植物内Foxp3表达.Treg与Teff加或不加OX40激动剂(OX86)以不同比例共培养,检测Teff增殖抑制情况.结果 RM134L+ MR1组MST为>150 d(n =8),较IgG组(19d,n=5)和联合PC61组(23 d,n=4)明显延长(P<0.05).同或不同MHC的2次胰岛移植MST分别为>60 d(n=3)和17 d(n =3) (P <0.05).OX40在Teff不表达,在野生型和CD154敲除小鼠Treg表达.3组小鼠胰岛移植物内Foxp3相对表达量分别为8、21、123 AU(P <0.05).Teff与Treg以1∶2和1∶4共培养,β-液体闪烁计数仪测定Teff的核素每分钟计数(CPM)分别为63×103和41×103,与对照组(140×103)比较增殖受抑制(P<0.05),加OX86时CPM值分别为128×103和135×103 (P >0.05).结论 CD4+ CD25+ Treg在诱导移植耐受中发挥重要作用,OX40在其中发挥负性调节作用.%Objective To observe the role of OX40/OX40L costimulation pathway in the CD4+CD25 + regulatory T (Treg) cells-induced tolerance of islet transplantation.Methods Diabetes mellitus was induced in C57BL/6 mice as recipients,and islets from DBA/2 mice were transplanted into the C57BL/6 mice.The recipients were divided into three groups (n =8):treated with IgG as controls,antiOX40L mAb (RM134L) + anti-CD154 mAb (MR1),and RM134L + MR1 + anti-CD25 mAb.The mean survival time (MST) of allograft was observed.The expression of OX40 in T effector cells,Treg cells of wide type and CD154 knock-out mice was detected.The expression of Foxp3 gene in

  14. Cutting Edge: Innate Lymphoid Cells Suppress Homeostatic T Cell Expansion in Neonatal Mice.

    Science.gov (United States)

    Bank, Ute; Deiser, Katrin; Finke, Daniela; Hämmerling, Günter J; Arnold, Bernd; Schüler, Thomas

    2016-05-01

    In adult mice, lymphopenia-induced proliferation (LIP) leads to T cell activation, memory differentiation, tissue destruction, and a loss of TCR diversity. Neonatal mice are lymphopenic within the first week of life. This enables some recent thymic emigrants to undergo LIP and convert into long-lived memory T cells. Surprisingly, however, most neonatal T cells do not undergo LIP. We therefore asked whether neonate-specific mechanisms prevent lymphopenia-driven T cell activation. In this study, we show that IL-7R-dependent innate lymphoid cells (ILCs) block LIP of CD8(+) T cells in neonatal but not adult mice. Importantly, CD8(+) T cell responses against a foreign Ag are not inhibited by neonatal ILCs. This ILC-based inhibition of LIP ensures the generation of a diverse naive T cell pool in lymphopenic neonates that is mandatory for the maintenance of T cell homeostasis and immunological self-tolerance later in life.

  15. A Human Vaccine Strategy Based On Chimpanzee Adenoviral and MVA Vectors That Primes, Boosts and Sustains Functional HCV Specific T-Cell Memory*

    Science.gov (United States)

    Swadling, Leo; Capone, Stefania; Antrobus, Richard D.; Brown, Anthony; Richardson, Rachel; Newell, Evan W.; Halliday, John; Kelly, Christabel; Bowen, Dan; Fergusson, Joannah; Kurioka, Ayako; Ammendola, Virginia; Sorbo, Mariarosaria Del; Grazioli, Fabiana; Esposito, Maria Luisa; Siani, Loredana; Traboni, Cinzia; Hill, Adrian; Colloca, Stefano; Davis, Mark; Nicosia, Alfredo; Cortese, Riccardo; Folgori, Antonella; Klenerman, Paul; Barnes, Eleanor

    2015-01-01

    A protective vaccine against hepatitis C virus (HCV) remains an unmet clinical need. HCV infects millions of people worldwide and is a leading cause of liver cirrhosis and hepatocellular cancer. Animal challenge experiments, immunogenetics studies and assessment of host immunity during acute infection highlight the critical role that effective T-cell immunity plays in viral control. In this first-in-man study we have induced antiviral immunity with functional characteristics analogous to those associated with viral control in natural infection, and improved upon a vaccine based on adenoviral vectors alone. We assessed a heterologous prime-boost vaccination strategy based on a replicative defective simian adenoviral vector (ChAd3) and modified vaccinia Ankara (MVA) vector encoding the NS3, NS4, NS5A and NS5B proteins of HCV genotype-1b. Analysis employed single cell mass cytometry (CyTOF), and HLA class-I peptide tetramer technology in healthy human volunteers. We show that HCV specific T-cells induced by ChAd3 are optimally boosted with MVA, and generate very high levels of both CD8+ and CD4+ HCV specific T-cells targeting multiple HCV antigens. Sustained memory and effector T-cell populations are generated and T-cell memory evolved over time with improvement of quality (proliferation and polyfunctionality) following heterologous MVA boost. We have developed a HCV vaccine strategy, with durable, broad, sustained and balanced T-cell responses, characteristic of those associated with viral control, paving the way for the first efficacy studies of a prophylactic HCV vaccine. PMID:25378645

  16. The role of CD8+ T cells during allograft rejection

    Directory of Open Access Journals (Sweden)

    Bueno V.

    2002-01-01

    Full Text Available Organ transplantation can be considered as replacement therapy for patients with end-stage organ failure. The percent of one-year allograft survival has increased due, among other factors, to a better understanding of the rejection process and new immunosuppressive drugs. Immunosuppressive therapy used in transplantation prevents activation and proliferation of alloreactive T lymphocytes, although not fully preventing chronic rejection. Recognition by recipient T cells of alloantigens expressed by donor tissues initiates immune destruction of allogeneic transplants. However, there is controversy concerning the relative contribution of CD4+ and CD8+ T cells to allograft rejection. Some animal models indicate that there is an absolute requirement for CD4+ T cells in allogeneic rejection, whereas in others CD4-depleted mice reject certain types of allografts. Moreover, there is evidence that CD8+ T cells are more resistant to immunotherapy and tolerance induction protocols. An intense focal infiltration of mainly CD8+CTLA4+ T lymphocytes during kidney rejection has been described in patients. This suggests that CD8+ T cells could escape from immunosuppression and participate in the rejection process. Our group is primarily interested in the immune mechanisms involved in allograft rejection. Thus, we believe that a better understanding of the role of CD8+ T cells in allograft rejection could indicate new targets for immunotherapy in transplantation. Therefore, the objective of the present review was to focus on the role of the CD8+ T cell population in the rejection of allogeneic tissue.

  17. Increased sensitivity to interferon-alpha in psoriatic T cells

    DEFF Research Database (Denmark)

    Eriksen, Karsten Wessel; Lovato, Paola; Skov, Lone;

    2005-01-01

    disease characterized by CD8(+)-infiltrating T cells. In this study, we therefore investigate IFN-alpha signaling in T cells isolated from involved skin of psoriatic patients. We show that psoriatic T cells have increased and prolonged responses to IFN-alpha, on the level of signal transducers......Psoriasis is a chronic inflammatory skin disease characterized by abnormal epidermal proliferation. Several studies have shown that skin-infiltrating activated T cells and cytokines play a pivotal role during the initiation and maintenance of the disease. Interferon (IFN)-alpha plays an important...... role in host defense against infections, but recent data have also implicated IFN-alpha in psoriasis. Thus, IFN-alpha induces or aggravates psoriasis in some patients, and mice lacking a transcriptional attenuator of IFN-alpha/beta signaling spontaneously develop a psoriasis-like inflammatory skin...

  18. Control of T cell antigen reactivity via programmed TCR downregulation.

    Science.gov (United States)

    Gallegos, Alena M; Xiong, Huizhong; Leiner, Ingrid M; Sušac, Bože; Glickman, Michael S; Pamer, Eric G; van Heijst, Jeroen W J

    2016-04-01

    The T cell antigen receptor (TCR) is unique in that its affinity for ligand is unknown before encounter and can vary by orders of magnitude. How the immune system regulates individual T cells that display very different reactivity to antigen remains unclear. Here we found that activated CD4(+) T cells, at the peak of clonal expansion, persistently downregulated their TCR expression in proportion to the strength of the initial antigen recognition. This programmed response increased the threshold for cytokine production and recall proliferation in a clone-specific manner and ultimately excluded clones with the highest antigen reactivity. Thus, programmed downregulation of TCR expression represents a negative feedback mechanism for constraining T cell effector function with a suitable time delay to thereby allow pathogen control while avoiding excess inflammatory damage. PMID:26901151

  19. 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.

  20. T Cell Integrin Overexpression as a Model of Murine Autoimmunity

    Directory of Open Access Journals (Sweden)

    Yung Raymond L.

    2003-01-01

    Full Text Available Integrin adhesion molecules have important adhesion and signaling functions. They also play a central role in the pathogenesis of many autoimmune diseases. Over the past few years we have described a T cell adoptive transfer model to investigate the role of T cell integrin adhesion molecules in the development of autoimmunity. This report summarizes the methods we used in establishing this murine model. By treating murine CD4+ T cells with DNA hypomethylating agents and by transfection we were able to test the in vitro effects of integrin overexpression on T cell autoreactive proliferation, cytotoxicity, adhesion and trafficking. Furthermore, we showed that the ability to induce in vivo autoimmunity may be unique to the integrin lymphocyte function associated antigen-1 (LFA-1.

  1. Vitamin E reverses impaired linker for activation of T cells activation in T cells from aged C57BL/6 mice

    Science.gov (United States)

    Supplemental vitamin E restores age-related defects in IL-2 production, T cell proliferation, and immune synapse formation. Here, we evaluated the effect of vitamin E on TCR-proximal signaling events. In aged murine CD4+ T cells stimulated via CD3 and CD28, tyrosine 191 of the adaptor protein LAT wa...

  2. Fas-mediated apoptosis regulates the composition of peripheral alphabeta T cell repertoire by constitutively purging out double negative T cells.

    Directory of Open Access Journals (Sweden)

    Abdiaziz S Mohamood

    Full Text Available BACKGROUND: The Fas pathway is a major regulator of T cell homeostasis, however, the T cell population that is controlled by the Fas pathway in vivo is poorly defined. Although CD4 and CD8 single positive (SP T cells are the two major T cell subsets in the periphery of wild type mice, the repertoire of mice bearing loss-of-function mutation in either Fas (lpr mice or Fas ligand (gld mice is predominated by CD4(-CD8(- double negative alphabeta T cells that also express B220 and generally referred to as B220+DN T cells. Despite extensive analysis, the basis of B220+DN T cell lymphoproliferation remains poorly understood. In this study we re-examined the issue of why T cell lymphoproliferation caused by gld mutation is predominated by B220+DN T cells. METHODOLOGY AND PRINCIPAL FINDINGS: We combined the following approaches to study this question: Gene transcript profiling, BrdU labeling, and apoptosis assays. Our results show that B220+DN T cells are proliferating and dying at exceptionally high rates than SP T cells in the steady state. The high proliferation rate is restricted to B220+DN T cells found in the gut epithelium whereas the high apoptosis rate occurred both in the gut epithelium and periphery. However, only in the periphery, apoptosis of B220+DN T cell is Fas-dependent. When the Fas pathway is genetically impaired, apoptosis of peripheral B220+DN T cells was reduced to a baseline level similar to that of SP T cells. Under these conditions of normalized apoptosis, B220+DN T cells progressively accumulate in the periphery, eventually resulting in B220+DN T cell lymphoproliferation. CONCLUSIONS/SIGNIFICANCE: The Fas pathway plays a critical role in regulating the tissue distribution of DN T cells through targeting and elimination of DN T cells from the periphery in the steady state. The results provide new insight into pathogenesis of DN T cell lymphoproliferation.

  3. Proliferation of and production of interferon-γ by drug-specific peripheral T cells from pafients with severe drug eruption%重症药疹患者外周血药物特异性T细胞扩增及干扰素γ产生的研究

    Institute of Scientific and Technical Information of China (English)

    高杨; 付萌; 史晓蔚; 廖文俊; 高琳; 高天文; 王刚; 李承新; 刘玉峰

    2010-01-01

    目的 检测重症药疹患者外周血中药物特异性T细胞扩增及干扰素γ(IFN-γ)产生情况.方法 共收集10例重症药疹门诊患者,分离患者外周血单一核细胞(PBMC),经相应的致敏药物刺激后培养出T细胞株,用体外ELISpot和培养ELISpot方法检测患者PBMC及药物特异性T细胞株分泌IFN-γ的情况.对10例患者同时设立与致敏药物分子结构不同的无关药物对照组.结果 重症药疹组中的10例患者PBMC、药物特异性T细胞株经致敏药物刺激后,IFN-γ的分泌明显高于正常对照组(P<0.01),且T细胞株经药物刺激后IFN-γ的分泌显著高于PBMC组(P<0.01).与致敏药物分子结构不同的无关对照药物不能够使药疹患者PBMC产生IFN-γ,不能培养出相应的T细胞.3例重症药疹患者治愈1~3年后,PBMC中仍存在药物特异性T细胞.结论 重症药疹患者体内存在药物特异性T细胞.体外ELISpot联合培养ELISpot方法在体外检测可能有助于致敏药物的鉴定.药疹患者治愈后体内持续存在药物特异性T细胞.%Objective To detect the proliferation of and production of interferon-γ by drug-specific peripheral T cells from patients with severe drug eruption.Methods Peripheral blood mononuclear cells (PBMCs) were isolated from 10 patients with severe drug eruption,10 patients with mild or moderate drug eruption and 10 normal human controls,stimulated with causative drugs to obtain drug-specific T cells.Then,both PBMCs and drug-specific T cells were stimulated with causative drugs or unrelated drugs followed by the detection of secretion levels of IFN-γ with ex vivo enzyme-linked immunodotting (ELISpot) assay and cultured ELlSpot assav respectively.Results After stimulation with causative drugs,a higher level of IFN-γ was secreted by PBMCs and drug-specific T cells from patients with severe drug eruption compared with those from normal human controls (both P<0.01).and by drug-specific T cells than by PBMCs (P<0

  4. Lung-resident tissue macrophages generate Foxp3+ regulatory T cells and promote airway tolerance

    OpenAIRE

    Soroosh, Pejman; Doherty, Taylor A.; Duan, Wei; Mehta, Amit Kumar; Choi, Heonsik; Adams, Yan Fei; Mikulski, Zbigniew; Khorram, Naseem; Rosenthal, Peter; Broide, David H.; Croft, Michael

    2013-01-01

    Airway tolerance is the usual outcome of inhalation of harmless antigens. Although T cell deletion and anergy are likely components of tolerogenic mechanisms in the lung, increasing evidence indicates that antigen-specific regulatory T cells (inducible Treg cells [iTreg cells]) that express Foxp3 are also critical. Several lung antigen-presenting cells have been suggested to contribute to tolerance, including alveolar macrophages (MØs), classical dendritic cells (DCs), and plasmacytoid DCs, b...

  5. Heterosubtypic T-Cell Immunity to Influenza in Humans: Challenges for Universal T-Cell Influenza Vaccines

    Science.gov (United States)

    Sridhar, Saranya

    2016-01-01

    Influenza A virus (IAV) remains a significant global health issue causing annual epidemics, pandemics, and sporadic human infections with highly pathogenic avian or swine influenza viruses. Current inactivated and live vaccines are the mainstay of the public health response to influenza, although vaccine efficacy is lower against antigenically distinct viral strains. The first pandemic of the twenty-first century underlined the urgent need to develop new vaccines capable of protecting against a broad range of influenza strains. Such “universal” influenza vaccines are based on the idea of heterosubtypic immunity, wherein immune responses to epitopes conserved across IAV strains can confer protection against subsequent infection and disease. T-cells recognizing conserved antigens are a key contributor in reducing viral load and limiting disease severity during heterosubtypic infection in animal models. Recent studies undertaken during the 2009 H1N1 pandemic provided key insights into the role of cross-reactive T-cells in mediating heterosubtypic protection in humans. This review focuses on human influenza to discuss the epidemiological observations that underpin cross-protective immunity, the role of T-cells as key players in mediating heterosubtypic immunity including recent data from natural history cohort studies and the ongoing clinical development of T-cell-inducing universal influenza vaccines. The challenges and knowledge gaps for developing vaccines to generate long-lived protective T-cell responses is discussed. PMID:27242800

  6. Heterosybtypic T-cell immunity to influenza in humans: challenges for universal T-cell influenza vaccines

    Directory of Open Access Journals (Sweden)

    Saranya eSridhar

    2016-05-01

    Full Text Available Influenza A virus (IAV remains a significant global health issue causing annual epidemics, pandemics and sporadic human infections with highly pathogenic avian or swine influenza viruses. Current inactivated and live vaccines are the mainstay of the public health response to influenza although vaccine efficacy is lower against antigenically distinct viral strains. The first pandemic of the 21st century underlined the urgent need to develop new vaccines capable of protection against a broad range of influenza strains. Such universal influenza vaccines are based on the idea of heterosubtypic immunity wherein immune responses to epitopes conserved across IAV strains can confer protection against subsequent infection and disease. T-cells recognising conserved antigens are a key contributor to reducing viral load and limiting disease severity during heterosubtypic infection in animal models. Recent studies undertaken during the 2009 H1N1 pandemic provided key insights into the role of cross-reactive T-cells in mediating heterosubtypic protection in humans. This review focuses on human influenza to discuss the epidemiological observations that underpin cross-protective immunity, the role of T-cells as key players in mediating heterosubtypic immunity including recent data from natural history cohort studies and the ongoing clinical development of T-cell inducing universal influenza vaccines. The challenges and knowledge gaps for developing vaccines to generate long-lived protective T-cell responses is discussed.

  7. Production of antigen-specific suppressive T cell factor by radiation leukemia virus-transformed suppressor T cells

    International Nuclear Information System (INIS)

    Hen egg-white lysozyme-specific suppressor T cells induced in C57BL/6 mice have been selected by sequential passage over plates coated with goat anti-mouse Ig and HEL. These suppressor T cells, 80% I-J+, were infected in vitro with radiation leukemia virus and injected intravenously into sublethally irradiated syngeneic recipients. After 4 to 6 months, 6 out of 20 injected mice developed thymic lymphomas, which were maintained by transplantation into histocompatible hosts and subsequently established as permanent cell lines. Cells of these six thymomas were screened for the presence of Thy 1.2, Lyt 1, Lyt 2, I-J/sup b/, and Ig cell surface antigens by direct or indirect immunofluorescence. One tumor was found to express the expected phenotype of suppressor T cells. High-speed supernatants of extracts obtained from L4 cells were able to induce HEL-specific suppression in a T cell proliferative assay, demonstrating the presence of an antigen-specific suppressive T cell factor

  8. 凉血活血复方对体外培养HaCaT细胞增殖和凋亡的影响%Effects of Liangxue Huoxue Complex Prescription on Proliferation and Apoptosis of HaCaT Cells in Vitro

    Institute of Scientific and Technical Information of China (English)

    周梅娟; 李玉峰; 刘晓明; 林熙然

    2011-01-01

    Objective To investigate the effects and effective concentration of the traditional Chinese medicine, the crude extract of Liangxue Huoxue complex prescription with water and alcohol, on proliferation and apoptosis of keratinocyte HaCaT cells. Methods Cultured HaCaT cells in vitro were exposed to the crude extract of Liangxue Huoxue complex prescription at different concentrations. Inhibition on cell proliferation was measured by MTT assay.' Morphological changes were observed under inverted microscope and transmission electron microscope. Cell cycle and apoptosis were analyzed by flow cytometry. Results The crude extract of Liangxue Huoxue complex prescription inhibited the proliferation of HaCaT cells in a time and concentration-dependent mode. The ICSO of the crude extract of Liangxue Huoxue complex prescription acted to HaCaT cell for 24h, 48h and 72h were 155.83mg/mL, 71.57 mg/mL and 41.27 mg/mL respectively. Cell morphological changes and flow cytometry analysis demonstrated that the crude extract of Liangxue Huoxue complex prescription could arrest HaCaT cells in Cj/M phase and induce apoptosis in a concentration-dependent manner. Conclusion The crude extract of Liangxue Huoxue complex prescription might inhibit keratinocytes proliferation and induce apoptosis in the treatment of psoriasis.%目的 观察中药凉血活血复方水醇粗提液对人永生化表皮细胞(HaCaT)的增殖抑制效应和诱导细胞凋亡作用的影响,探讨该复方治疗银屑痛的可能机制.方法 将不同浓度的凉血活血复方水醇粗提液分别作用于体外培养的HaCaT细胞,采用MTT法检测凉血活血复方水醇粗提液对细胞的增殖抑制作用以及药物的有效浓度;采用倒置显微镜、透射电子显微镜观察细胞处理前后的形态学改变:流式细胞术检测细胞周期的变化及凋亡比率.结果 凉血活血复方以时间和浓度依赖性方式抑制HaCaT细胞增殖,作用24、48、72h其IC50分别为155.83 mg

  9. T cell metabolism. The protein LEM promotes CD8⁺ T cell immunity through effects on mitochondrial respiration.

    Science.gov (United States)

    Okoye, Isobel; Wang, Lihui; Pallmer, Katharina; Richter, Kirsten; Ichimura, Takahuru; Haas, Robert; Crouse, Josh; Choi, Onjee; Heathcote, Dean; Lovo, Elena; Mauro, Claudio; Abdi, Reza; Oxenius, Annette; Rutschmann, Sophie; Ashton-Rickardt, Philip G

    2015-05-29

    Protective CD8(+) T cell-mediated immunity requires a massive expansion in cell number and the development of long-lived memory cells. Using forward genetics in mice, we identified an orphan protein named lymphocyte expansion molecule (LEM) that promoted antigen-dependent CD8(+) T cell proliferation, effector function, and memory cell generation in response to infection with lymphocytic choriomeningitis virus. Generation of LEM-deficient mice confirmed these results. Through interaction with CR6 interacting factor (CRIF1), LEM controlled the levels of oxidative phosphorylation (OXPHOS) complexes and respiration, resulting in the production of pro-proliferative mitochondrial reactive oxygen species (mROS). LEM provides a link between immune activation and the expansion of protective CD8(+) T cells driven by OXPHOS and represents a pathway for the restoration of long-term protective immunity based on metabolically modified cytotoxic CD8(+) T cells.

  10. Double-Negative αβ T Cells Are Early Responders to AKI and Are Found in Human Kidney.

    Science.gov (United States)

    Martina, Maria N; Noel, Sanjeev; Saxena, Ankit; Bandapalle, Samatha; Majithia, Richa; Jie, Chunfa; Arend, Lois J; Allaf, Mohamad E; Rabb, Hamid; Hamad, Abdel Rahim A

    2016-04-01

    Ischemia-reperfusion injury (IRI) is a major cause of AKI, and previous studies established important roles for conventional CD4(+) T cells, natural killer T cells, and CD4(+)CD25(+)FoxP3(+) Tregs in AKI pathogenesis. We recently identified CD4(-)CD8(-) (double-negative; DN) T cells as an important subset of αβ T cell receptor-positive cells residing in mouse kidney. However, little is known about the pathophysiologic functions of kidney DN T cells. In this study, we phenotypically and functionally characterized murine kidney DN T cells in the steady state and in response to IRI. Unlike CD4(+) and CD8(+) T cells, DN T cells in the steady state expressed high levels of CD69, CD28, and CD40L; differentially expressed IL-27 and IL-10 anti-inflammatory cytokines; spontaneously proliferated at a very high rate; and suppressed in vitro proliferation of activated CD4(+) T cells. Within the first 3-24 hours after IRI, kidney DN T cells expanded significantly and upregulated expression of IL-10. In adoptive transfer experiments, DN T cells significantly protected recipients from AKI by an IL-10-dependent mechanism. DN T cells also made up a large fraction of the T cell compartment in human kidneys. Our results indicate that DN T cells are an important subset of the resident αβ(+) T cell population in the mammalian kidney and are early responders to AKI that have anti-inflammatory properties.

  11. Memory CD4+ T cells do not induce graft-versus-host disease.

    Science.gov (United States)

    Anderson, Britt E; McNiff, Jennifer; Yan, Jun; Doyle, Hester; Mamula, Mark; Shlomchik, Mark J; Shlomchik, Warren D

    2003-07-01

    Graft-versus-host disease (GVHD) remains a major cause of morbidity and mortality in allogeneic stem cell transplantation (alloSCT). Donor T cells that accompany stem cell grafts cause GVHD by attacking recipient tissues; therefore, all patients receive GVHD prophylaxis by depletion of T cells from the allograft or through immunosuppressant drugs. In addition to providing a graft-versus-leukemia effect, donor T cells are critical for reconstituting T cell-mediated immunity. Ideally, immunity to infectious agents would be transferred from donor to host without GVHD. Most donors have been exposed to common pathogens and have an increased precursor frequency of memory T cells against pathogenic antigens. We therefore asked whether memory CD62L-CD44+ CD4+ T cells would induce less GVHD than unfractionated or naive CD4+ T cells. Strikingly, we found that memory CD4 cells induced neither clinical nor histologic GVHD. This effect was not due to the increased number of CD4+CD25+ regulatory T cells found in the CD62L-CD44+ fraction because memory T cells depletion of these cells did not cause GVHD. Memory CD4 cells engrafted and responded to antigen both in vivo and in vitro. If these murine results are applicable to human alloSCT, selective administration of memory T cells could greatly improve post-transplant immune reconstitution.

  12. To investigate the necessity of STRA6 upregulation in T cells during T cell immune responses.

    Directory of Open Access Journals (Sweden)

    Rafik Terra

    Full Text Available Our earlier study revealed that STRA6 (stimulated by retinoic acid gene 6 was up-regulated within 3 h of TCR stimulation. STRA6 is the high-affinity receptor for plasma retinol-binding protein (RBP and mediates cellular vitamin A uptake. We generated STRA6 knockout (KO mice to assess whether such up-regulation was critical for T-cell activation, differentiation and function. STRA6 KO mice under vitamin A sufficient conditions were fertile without apparent anomalies upon visual inspection. The size, cellularity and lymphocyte subpopulations of STRA6 KO thymus and spleen were comparable to those of their wild type (WT controls. KO and WT T cells were similar in terms of TCR-stimulated proliferation in vitro and homeostatic expansion in vivo. Naive KO CD4 cells differentiated in vitro into Th1, Th2, Th17 as well as regulatory T cells in an analogous manner as their WT counterparts. In vivo experiments revealed that anti-viral immune responses to lymphocytic choriomeningitis virus in KO mice were comparable to those of WT controls. We also demonstrated that STRA6 KO and WT mice had similar glucose tolerance. Total vitamin A levels are dramatically lower in the eyes of KO mice as compared to those of WT mice, but the levels in other organs were not significantly affected after STRA6 deletion under vitamin A sufficient conditions, indicating that the eye is the mouse organ most sensitive to the loss of STRA6. Our results demonstrate that 1 in vitamin A sufficiency, the deletion of STRA6 in T cells does no affect the T-cell immune responses so-far tested, including those depend on STAT5 signaling; 2 STRA6-independent vitamin A uptake compensated the lack of STRA6 in lymphoid organs under vitamin A sufficient conditions in mice; 3 STRA6 is critical for vitamin A uptake in the eyes even in vitamin A sufficiency.

  13. Assay of Peripheral Regulatory Vδ1 T Cells in Ankylosing Spondylitis and its Significance

    Science.gov (United States)

    Wang, Hongliang; Sun, Na; Li, Ka; Tian, Jiguang; Li, Jianmin

    2016-01-01

    Background Ankylosing spondylitis (AS) involves inflammation at the sacroiliac joint and spine attachment site. This study aimed to observe the ratio and function of peripheral regulatory Vδ1 T cells in AS patients to investigate their roles in AS pathogenesis. Material/Methods Peripheral blood mononuclear cells (PBMC) were separated by density-gradient centrifugation from AS patients and healthy controls. Flow cytometry was used to determine the ratio between Vδ1 and CD4 T cells of PBMC in AS patients and controls. Flow cytometry sorting (FCS) was used to obtain Vδ1 and naïve CD4 T cells with purity higher than 90%. CFSE staining method was used to detect the effect of Vδ1 T cells on proliferation of naïve CD4 T cells. The effect of Vδ1 T cells on secretion of IFN-γ from naïve CD4 T cells and the ability to secrete IL-10 from Vδ1 T cells were determined by flow cytometry. Results AS patients had significantly lower Vδ1 T cell ratio in PBMC compared to controls (p<0.05), but their CD4 T cell ratio was significantly elevated (p<0.05). Functional assay showed suppression of naïve CD4 T cell proliferation and IFN-γ secretion by peripheral Vδ1 T cells in AS patients (p<0.01). AS patients also had lower IL-10 secreting level from peripheral derived Vδ1 T cells (p<0.01). Conclusions The immune suppression of peripheral Vδ1 T cell in AS patient increases the ratio of peripheral CD4 T cells and IFN-γ level, leading to AS pathogenesis. This immune suppression is mainly due to suppressed IL-10 secretion. PMID:27598263

  14. 绿茶和红茶提取物抑制中波紫外线诱导HaCaT细胞氧化损伤和凋亡的比较%Comparation the inbibitional effects between extracts of green tea and black tea on oxidative damage and apoptosis of HaCaT cells induced by UVB

    Institute of Scientific and Technical Information of China (English)

    马蕊; 刘仲华; 黄建安; 林勇; 陈金华; 钟源

    2013-01-01

    To compare the photo-protective effect of green and black tea extracts on HaCaT cells damaged from ultraviolet radiation B.Sub-confluent HaCaT cells were incubated for 6 h with different doses of extracts from green tea and black tea,and then irradiated with 60 mJ/cm2 doses of UVB.The change of the cell viability,the activity of superoxide dismutase (SOD),glutathione peroxidase (GSH-Px),lactate dehydrogenase (LDH),and the level of malondialdehyde (MDA) of supernatant were compared.The content of ROS was measured with the fluorescence method.Annexin V/PI double staining was performed to evaluate the change of apoptosis using flow cytometry.In addition,the contents of tea polyphenols and catechins from extracts of green and black tea were also tested.The results were as follows:Compared with control group,the UVB irradiation could seriously harm HaCaT cell and gave rise to 21.61% cell viability decline.Extracts form green and black tea could enhance cell viability,SOD and GSH-Px activity in supernatant under UVB irradiation,and decrease LDH activity,the content of MDA and the content of ROS in cells in dose-dependent manner (P <0.01).Compared with UVB-irradiated model group,the apoptosis rate of HaCaT cell in other groups was decreased by 6.94% and 3.68% respectively.Moreover,the photo-protective effect of green tea extracts was better than that of black tea extracts,which were consistent with the content of tea polyphenols and catechins their contained.Green and black tea extracts could relieve UVB-induced oxidative damage and apoptosis of HaCaT cells,which might be the reason that they raised the oxidase activity and cleared the oxy-radicals in cells.Moreover,the photo-protective effect of green tea extracts against oxidative damage and apoptosis of HaCaT cells from UVB irradiation was better than that of black tea extracts.%为比较绿茶、红茶提取物对中波紫外线(UVB)诱导角质形成细胞光损伤的抑制作用,用不同浓度的绿茶、

  15. Characteristics and functions of Sendai virus-specific T-cell clones.

    OpenAIRE

    Ertl, H C; Finberg, R W

    1984-01-01

    Several murine Sendai virus-specific T-cell clones were characterized in vitro and in vivo. All T-cell clones were phenotypically Thy-1.2+, and most clones were Lyt-1+,2-; one T-cell clone was Lyt-1-,2-. Some of the clones proliferated in response to antigen presented on I region-compatible stimulator cells. Proliferation could be inhibited by monoclonal antibodies directed against class II antigens. Clones which proliferated in response to antigen secreted lymphokines which could be identifi...

  16. HIV-1 Nef enhances dendritic cell-mediated viral transmission to CD4+ T cells and promotes T-cell activation.

    Directory of Open Access Journals (Sweden)

    Corine St Gelais

    Full Text Available HIV-1 Nef enhances dendritic cell (DC-mediated viral transmission to CD4(+ T cells, but the underlying mechanism is not fully understood. It is also unknown whether HIV-1 infected DCs play a role in activating CD4(+ T cells and enhancing DC-mediated viral transmission. Here we investigated the role of HIV-1 Nef in DC-mediated viral transmission and HIV-1 infection of primary CD4(+ T cells using wild-type HIV-1 and Nef-mutated viruses. We show that HIV-1 Nef facilitated DC-mediated viral transmission to activated CD4(+ T cells. HIV-1 expressing wild-type Nef enhanced the activation and proliferation of primary resting CD4(+ T cells. However, when co-cultured with HIV-1-infected autologous DCs, there was no significant trend for infection- or Nef-dependent proliferation of resting CD4(+ T cells. Our results suggest an important role of Nef in DC-mediated transmission of HIV-1 to activated CD4(+ T cells and in the activation and proliferation of resting CD4(+ T cells, which likely contribute to viral pathogenesis.

  17. 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

  18. Clinical significance of T cell metabolic reprogramming in cancer.

    Science.gov (United States)

    Herbel, Christoph; Patsoukis, Nikolaos; Bardhan, Kankana; Seth, Pankaj; Weaver, Jessica D; Boussiotis, Vassiliki A

    2016-12-01

    Conversion of normal cells to cancer is accompanied with changes in their metabolism. During this conversion, cell metabolism undergoes a shift from oxidative phosphorylation to aerobic glycolysis, also known as Warburg effect, which is a hallmark for cancer cell metabolism. In cancer cells, glycolysis functions in parallel with the TCA cycle and other metabolic pathways to enhance biosynthetic processes and thus support proliferation and growth. Similar metabolic features are observed in T cells during activation but, in contrast to cancer, metabolic transitions in T cells are part of a physiological process. Currently, there is intense interest in understanding the cause and effect relationship between metabolic reprogramming and T cell differentiation. After the recent success of cancer immunotherapy, the crosstalk between immune system and cancer has come to the forefront of clinical and basic research. One of the key goals is to delineate how metabolic alterations of cancer influence metabolism-regulated function and differentiation of tumor resident T cells and how such effects might be altered by immunotherapy. Here, we review the unique metabolic features of cancer, the implications of cancer metabolism on T cell metabolic reprogramming during antigen encounters, and the translational prospective of harnessing metabolism in cancer and T cells for cancer therapy. PMID:27510264

  19. Development and characterization of Histoplasma capsulatum-reactive murine T-cell lines and clones.

    OpenAIRE

    Deepe, G S; Smith, J G; Sonnenfeld, G; Denman, D.; Bullock, W E

    1986-01-01

    Experimental studies have suggested that antigen-specific T lymphocytes are important mediators of resistance to infection with the pathogenic fungus Histoplasma capsulation. To gain a better understanding of the role of T lymphocytes, we developed murine T-cell lines and clones that recognized Histoplasma antigens. These T cells were of the helper/inducer phenotype (Thy-1.2+ Lyt-1+ L3T4+ Lyt-2-) and exerted multiple immunological functions. T-cell lines and 12 clones proliferated vigorously ...

  20. E2a/Pbx1 Induces the Rapid Proliferation of Stem Cell Factor-Dependent Murine Pro-T Cells That Cause Acute T-Lymphoid or Myeloid Leukemias in Mice

    OpenAIRE

    Sykes, David B.; Kamps, Mark P.

    2004-01-01

    Oncoprotein E2a/Pbx1 is produced by the t(1;19) chromosomal translocation of human pre-B acute lymphoblastic leukemia. E2a/Pbx1 blocks differentiation of primary myeloid progenitors but, paradoxically, induces apoptosis in established pre-B-cell lines, and no transforming function of E2a/Pbx1 has been reported in cultured lymphoid progenitors. Here, we demonstrate that E2a/Pbx1 induces immortal proliferation of stem cell factor (SCF)-dependent pro-T thymocytes by a mechanism dependent upon bo...

  1. Distinct T cell dynamics in lymph nodes during the induction of tolerance and immunity.

    Science.gov (United States)

    Hugues, Stéphanie; Fetler, Luc; Bonifaz, Laura; Helft, Julie; Amblard, François; Amigorena, Sebastian

    2004-12-01

    Induction of immunity and peripheral tolerance requires contacts between antigen-bearing dendritic cells (DCs) and cognate T cells. Using real-time two-photon microscopy, we have analyzed the dynamics of CD8(+) T cells in lymph nodes during the induction of antigen-specific immunity or tolerance. At 15-20 h after the induction of immunity, T cells stopped moving and established prolonged interactions with DCs. In tolerogenic conditions, despite effective initial T cell activation and proliferation, naive T cells remained motile and established serial brief contacts with multiple DCs. Thus, stable DC-T cell interactions occur during the induction of priming, whereas brief contacts may contribute to the induction of T cell tolerance.

  2. Fish T cells: recent advances through genomics

    Science.gov (United States)

    Laing, Kerry J.; Hansen, John D.

    2011-01-01

    This brief review is intended to provide a concise overview of the current literature concerning T cells, advances in identifying distinct T cell functional subsets, and in distinguishing effector cells from memory cells. We compare and contrast a wealth of recent progress made in T cell immunology of teleost, elasmobranch, and agnathan fish, to knowledge derived from mammalian T cell studies. From genome studies, fish clearly have most components associated with T cell function and we can speculate on the presence of putative T cell subsets, and the ability to detect their differentiation to form memory cells. Some recombinant proteins for T cell associated cytokines and antibodies for T cell surface receptors have been generated that will facilitate studying the functional roles of teleost T cells during immune responses. Although there is still a long way to go, major advances have occurred in recent years for investigating T cell responses, thus phenotypic and functional characterization is on the near horizon.

  3. 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...... with central roles in TCR signaling. The model was used to generate predictions suggesting unexpected roles for the phosphatase PTPN6 (SHP-1) and shortcut recruitment of the actin regulator WAS. Predictions were validated experimentally. This integration of proteomics and modeling illustrates a novel...

  4. Cutaneous T-cell lymphomas and their management strategies

    Directory of Open Access Journals (Sweden)

    S S Pandey

    2014-01-01

    Full Text Available Cutaneous T-cell lymphomas (CTCLs comprise a heterogeneous group of lymphoproliferative disorders characterized by the proliferation of skin-homing post-thymic T-cells. It is the second most common extranodal non-Hodgekin′s lymphoma. Many variants of mycosis fungoides and CTCLs are known to date, differing in clinical, histological, and immunophenotypic characteristics. Oral involvement has also been reported rarely in CTCLs. Treatment depends on the disease stage or the type of variant. New insights into the disease and the number of emerging novel therapeutic options have made it an interesting area for dermatologists and medical oncologists.

  5. Homocysteine activates T cells by enhancing endoplasmic reticulum-mitochondria coupling and increasing mitochondrial respiration.

    Science.gov (United States)

    Feng, Juan; Lü, Silin; Ding, Yanhong; Zheng, Ming; Wang, Xian

    2016-06-01

    Hyperhomocysteinemia (HHcy) accelerates atherosclerosis by increasing proliferation and stimulating cytokine secretion in T cells. However, whether homocysteine (Hcy)-mediated T cell activation is associated with metabolic reprogramming is unclear. Here, our in vivo and in vitro studies showed that Hcy-stimulated splenic T-cell activation in mice was accompanied by increased levels of mitochondrial reactive oxygen species (ROS) and calcium, mitochondrial mass and respiration. Inhibiting mitochondrial ROS production and calcium signals or blocking mitochondrial respiration largely blunted Hcy-induced T-cell interferon γ (IFN-γ) secretion and proliferation. Hcy also enhanced endoplasmic reticulum (ER) stress in T cells, and inhibition of ER stress with 4-phenylbutyric acid blocked Hcy-induced T-cell activation. Mechanistically, Hcy increased ER-mitochondria coupling, and uncoupling ER-mitochondria by the microtubule inhibitor nocodazole attenuated Hcy-stimulated mitochondrial reprogramming, IFN-γ secretion and proliferation in T cells, suggesting that juxtaposition of ER and mitochondria is required for Hcy-promoted mitochondrial function and T-cell activation. In conclusion, Hcy promotes T-cell activation by increasing ER-mitochondria coupling and regulating metabolic reprogramming.

  6. Mannose-Capped Lipoarabinomannan from Mycobacterium tuberculosis Induces CD4+ T Cell Anergy via GRAIL.

    Science.gov (United States)

    Sande, Obondo J; Karim, Ahmad F; Li, Qing; Ding, Xuedong; Harding, Clifford V; Rojas, Roxana E; Boom, W Henry

    2016-01-15

    Mycobacterium tuberculosis cell wall glycolipid, lipoarabinomannan, can inhibit CD4(+) T cell activation by downregulating the phosphorylation of key proximal TCR signaling molecules: Lck, CD3ζ, ZAP70, and LAT. Inhibition of proximal TCR signaling can result in T cell anergy, in which T cells are inactivated following an Ag encounter, yet remain viable and hyporesponsive. We tested whether mannose-capped lipoarabinomannan (LAM)-induced inhibition of CD4(+) T cell activation resulted in CD4(+) T cell anergy. The presence of LAM during primary stimulation of P25 TCR-transgenic murine CD4(+) T cells with M. tuberculosis Ag85B peptide resulted in decreased proliferation and IL-2 production. P25 TCR-transgenic CD4(+) T cells primed in the presence of LAM also exhibited decreased response upon restimulation with Ag85B. The T cell anergic state persisted after the removal of LAM. Hyporesponsiveness to restimulation was not due to apoptosis, generation of Foxp3-positive regulatory T cells, or inhibitory cytokines. Acquisition of the anergic phenotype correlated with upregulation of gene related to anergy in lymphocytes (GRAIL) protein in CD4(+) T cells. Inhibition of human CD4(+) T cell activation by LAM also was associated with increased GRAIL expression. Small interfering RNA-mediated knockdown of GRAIL before LAM treatment abrogated LAM-induced hyporesponsiveness. In addition, exogenous IL-2 reversed defective proliferation by downregulating GRAIL expression. These results demonstrate that LAM upregulates GRAIL to induce anergy in Ag-reactive CD4(+) T cells. Induction of CD4(+) T cell anergy by LAM may represent one mechanism by which M. tuberculosis evades T cell recognition. PMID:26667170

  7. 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

    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...

  8. CD4+CD25+ regulatory T cells: I. Phenotype and physiology

    DEFF Research Database (Denmark)

    Holm, Thomas Lindebo; Nielsen, Janne; Claesson, Mogens H

    2004-01-01

    it has become increasingly clear that regulatory CD4+CD25+ T cells (Treg cells) play an important role in the maintenance of immunological self-tolerance, and that this cell subset exerts its function by suppressing the proliferation or function of autoreactive T cells. Based on human and murine...

  9. Reactivity of naive CD4+CD25- T cells against gut microflora in healthy mice

    DEFF Research Database (Denmark)

    Gad, Monika; Lundsgaard, Dorthe; Kjellev, Stine;

    2006-01-01

    We have previously shown that conventional as well as germ-free CD4+ T cells depleted of CD25+ cells from the gut-associated lymphoid tissue and the periphery proliferate specifically in response to enterobacterial antigen exposure whereas unfractionated CD4+ T cells are not reactive under these ...

  10. A repertoire-independent and cell-intrinsic defect in murine GVHD induction by effector memory T cells

    OpenAIRE

    Juchem, Kathryn W.; Anderson, Britt E.; Zhang, Cuiling; McNiff, Jennifer M.; DEMETRIS, ANTHONY J.; Farber, Donna L.; Caton, Andrew J.; Shlomchik, Warren D.; Shlomchik, Mark J.

    2011-01-01

    Effector memory T cells (TEM) do not cause graft-versus-host disease (GVHD), though why this is has not been elucidated. To compare the fates of alloreactive naive (TN) or memory (TM) T cells, we developed a model of GVHD in which donor T cells express a transgene-encoded TCR specific for an antigenic peptide that is ubiquitously expressed in the recipient. Small numbers of naive TCR transgenic (Tg) T cells induced a robust syndrome of GVHD in transplanted recipients. We then used an establis...

  11. Aspects of T Cell-Mediated Immunity Induced in Mice by a DNA Vaccine Based on the Dengue-NS1 Antigen after Challenge by the Intracerebral Route.

    Science.gov (United States)

    Oliveira, Edson R A; Gonçalves, Antônio J S; Costa, Simone M; Azevedo, Adriana S; Mantuano-Barradas, Marcio; Nogueira, Ana Cristina M A; Alves, Ada M B

    2016-01-01

    Dengue disease has emerged as a major public health issue across tropical and subtropical countries. Infections caused by dengue virus (DENV) can evolve to life-threatening forms, resulting in about 20,000 deaths every year worldwide. Several animal models have been described concerning pre-clinical stages in vaccine development against dengue, each of them presenting limitations and advantages. Among these models, a traditional approach is the inoculation of a mouse-brain adapted DENV variant in immunocompetent animals by the intracerebral (i.c.) route. Despite the historical usage and relevance of this model for vaccine testing, little is known about the mechanisms by which the protection is developed upon vaccination. To cover this topic, a DNA vaccine based on the DENV non-structural protein 1 (pcTPANS1) was considered and investigations were focused on the induced T cell-mediated immunity against i.c.-DENV infection. Immunophenotyping assays by flow cytometry revealed that immunization with pcTPANS1 promotes a sustained T cell activation in spleen of i.c.-infected mice. Moreover, we found that the downregulation of CD45RB on T cells, as an indicator of cell activation, correlated with absence of morbidity upon virus challenge. Adoptive transfer procedures supported by CFSE-labeled cell tracking showed that NS1-specific T cells induced by vaccination, proliferate and migrate to peripheral organs of infected mice, such as the liver. Additionally, in late stages of infection (from the 7th day onwards), vaccinated mice also presented reduced levels of circulating IFN-γ and IL-12p70 in comparison to non-vaccinated animals. In conclusion, this work presented new aspects about the T cell-mediated immunity concerning DNA vaccination with pcTPANS1 and the i.c. infection model. These insights can be explored in further studies of anti-dengue vaccine efficacy. PMID:27631083

  12. Aspects of T Cell-Mediated Immunity Induced in Mice by a DNA Vaccine Based on the Dengue-NS1 Antigen after Challenge by the Intracerebral Route

    Science.gov (United States)

    Oliveira, Edson R. A.; Gonçalves, Antônio J. S.; Costa, Simone M.; Azevedo, Adriana S.; Mantuano-Barradas, Marcio; Nogueira, Ana Cristina M. A.

    2016-01-01

    Dengue disease has emerged as a major public health issue across tropical and subtropical countries. Infections caused by dengue virus (DENV) can evolve to life-threatening forms, resulting in about 20,000 deaths every year worldwide. Several animal models have been described concerning pre-clinical stages in vaccine development against dengue, each of them presenting limitations and advantages. Among these models, a traditional approach is the inoculation of a mouse-brain adapted DENV variant in immunocompetent animals by the intracerebral (i.c.) route. Despite the historical usage and relevance of this model for vaccine testing, little is known about the mechanisms by which the protection is developed upon vaccination. To cover this topic, a DNA vaccine based on the DENV non-structural protein 1 (pcTPANS1) was considered and investigations were focused on the induced T cell-mediated immunity against i.c.-DENV infection. Immunophenotyping assays by flow cytometry revealed that immunization with pcTPANS1 promotes a sustained T cell activation in spleen of i.c.-infected mice. Moreover, we found that the downregulation of CD45RB on T cells, as an indicator of cell activation, correlated with absence of morbidity upon virus challenge. Adoptive transfer procedures supported by CFSE-labeled cell tracking showed that NS1-specific T cells induced by vaccination, proliferate and migrate to peripheral organs of infected mice, such as the liver. Additionally, in late stages of infection (from the 7th day onwards), vaccinated mice also presented reduced levels of circulating IFN-γ and IL-12p70 in comparison to non-vaccinated animals. In conclusion, this work presented new aspects about the T cell-mediated immunity concerning DNA vaccination with pcTPANS1 and the i.c. infection model. These insights can be explored in further studies of anti-dengue vaccine efficacy. PMID:27631083

  13. Murine regulatory T cells contain hyper-proliferative and death-prone subsets with differential ICOS expression

    OpenAIRE

    Chen, Yong; Shen, Shudan; Gorentla, Balachandra; Gao, Jimin; Zhong, Xiao-Ping

    2012-01-01

    Regulatory T cells (Treg) are crucial for self-tolerance. It has been an enigma that Treg exhibit an anergic phenotype reflected by hypo-proliferation in vitro following T cell receptor (TCR) stimulation but undergo vigorous proliferation in vivo. We report here that, different from conventional T cells (Tcon), murine Treg are prone to death but hyper-proliferative in vitro and in vivo. During in vitro culture, most Treg die with or without TCR stimulation, correlated with constitutive activa...

  14. Human regulatory T cell suppressive function is independent of apoptosis induction in activated effector T cells.

    Directory of Open Access Journals (Sweden)

    Yvonne Vercoulen

    Full Text Available BACKGROUND: CD4(+CD25(+FOXP3(+ Regulatory T cells (Treg play a central role in the immune balance to prevent autoimmune disease. One outstanding question is how Tregs suppress effector immune responses in human. Experiments in mice demonstrated that Treg restrict effector T cell (Teff responses by deprivation of the growth factor IL-2 through Treg consumption, resulting in apoptosis of Teff. PRINCIPAL FINDINGS: In this study we investigated the relevance of Teff apoptosis induction to human Treg function. To this end, we studied naturally occurring Treg (nTreg from peripheral blood of healthy donors, and, to investigate Treg function in inflammation in vivo, Treg from synovial fluid of Juvenile Idiopathic Arthritis (JIA patients (SF-Treg. Both nTreg and SF-Treg suppress Teff proliferation and cytokine production efficiently as predicted. However, in contrast with murine Treg, neither nTreg nor SF-Treg induce apoptosis in Teff. Furthermore, exogenously supplied IL-2 and IL-7 reverse suppression, but do not influence apoptosis of Teff. SIGNIFICANCE: Our functional data here support that Treg are excellent clinical targets to counteract autoimmune diseases. For optimal functional outcome in human clinical trials, future work should focus on the ability of Treg to suppress proliferation and cytokine production of Teff, rather than induction of Teff apoptosis.

  15. Peripheral blood lymphocytes from low-grade squamous intraepithelial lesions patients recognize vaccine antigens in the presence of activated dendritic cells, and produced high levels of CD8 + IFNγ + T cells and low levels of IL-2 when induced to proliferate

    Directory of Open Access Journals (Sweden)

    Hernández-Montes Jorge

    2012-05-01

    Full Text Available Abstract Background Most infections with human papillomavirus (HPV are resolved without clinical intervention, but a minority evolves into chronic lesions of distinct grades, including cervical-uterine cancer. It is known that in most cases the immune system mediates elimination of HPV infection. However, the mechanism of immune evasion leading to HPV persistence and development of early cervical lesions is not fully understood. The aim of the present work was to evaluate the potential of peripheral blood leukocytes (PBL from low-grade squamous intraepithelial lesions (LSIL patients to be activated ex-vivo by vaccine antigens, the participation of cytotoxic lymphocytes and regulatory T cells, and to determine the secretion of Th1 and Th2 cytokines mediated by stimulation of T cell receptors. Results We found that PBL from LSIL patients showed a significantly lower proliferation rate to vaccine antigens as compared to that of healthy donors, even though there was not a difference in the presence of antibodies to those antigens in sera from both groups. We did not find differences in either the frequency of CD4 + CD25 + FoxP3+ in PBL, or the levels of IL-4, IL-5 and IL-10 in plasma or conditioned media from PBL incubated with TcR agonists in vitro, between the two groups. However, we detected a lower production of IL-2 and a higher proportion of CD8 + IFNγ + cells in PBL from LSIL patients as compared with PBL from normal donors. We also observed that PBL from patients infected by HPV-16 and −18 were not able to proliferate in the presence of soluble HPV antigens added to the culture; however, a high level of proliferation was attained when these antigens were presented by activated dendritic cells. Conclusions Our results suggest that the immunodeficiency reported in LSIL patients could be due to the inability of specific cytotoxic T lymphocytes that for some unknown reason are present but unable to mount a response when

  16. Lack of p53 Augments Antitumor Functions in Cytolytic T Cells.

    Science.gov (United States)

    Banerjee, Anirban; Thyagarajan, Krishnamurthy; Chatterjee, Shilpak; Chakraborty, Paramita; Kesarwani, Pravin; Soloshchenko, Myroslawa; Al-Hommrani, Mazen; Andrijauskaite, Kristina; Moxley, Kelly; Janakiraman, Harinarayanan; Scheffel, Matthew J; Helke, Kristi; Armenson, Kent; Palanisamy, Viswanathan; Rubinstein, Mark P; Mayer, Elizabeth-Garrett; Cole, David J; Paulos, Chrystal M; Voelkel-Johnson, Christina; Nishimura, Michael I; Mehrotra, Shikhar

    2016-09-15

    Repetitive stimulation of T-cell receptor (TCR) with cognate antigen results in robust proliferation and expansion of the T cells, and also imprints them with replicative senescence signatures. Our previous studies have shown that life-span and antitumor function of T cells can be enhanced by inhibiting reactive oxygen species (ROS) or intervening with ROS-dependent JNK activation that leads to its activation-induced cell death. Because tumor suppressor protein p53 is also a redox active transcription factor that regulates cellular ROS generation that triggers downstream factor-mediating apoptosis, we determined if p53 levels could influence persistence and function of tumor-reactive T cells. Using h3T TCR transgenic mice, with human tyrosinase epitope-reactive T cells developed on p53 knockout (KO) background, we determined its role in regulating antitumor T-cell function. Our data show that as compared with h3T cells, h3T-p53 KO T cells exhibited enhanced glycolytic commitment that correlated with increased proliferation, IFNγ secretion, cytolytic capacity, expression of stemness gene signature, and decreased TGF-β signaling. This increased effector function correlated to the improved control of subcutaneously established murine melanoma after adoptive transfer of p53-KO T cells. Pharmacological inhibition of human TCR-transduced T cells using a combination of p53 inhibitors also potentiated the T-cell effector function and improved persistence. Thus, our data highlight the key role of p53 in regulating the tumor-reactive T-cell response and that targeting this pathway could have potential translational significance in adoptive T-cell therapy. Cancer Res; 76(18); 5229-40. ©2016 AACR.

  17. 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.

  18. Development and characterization of Histoplasma capsulatum-reactive murine T-cell lines and clones

    Science.gov (United States)

    Deepe, George S., Jr.; Smith, James G.; Denman, David; Bullock, Ward E.; Sonnenfeld, Gerald

    1986-01-01

    Several Histoplasma capsulatum-reactive murine cloned T-cell lines (TCLs) were isolated from spleens of C57BL/6 mice immunized with viable H. capsulatum yeast cells, using the methodology of Kimoto and Fathman (1980). These T-cells were characterized phenotypically as Thy-1.2(+) Lyt-1(+) L3T4(+) Lyt-2(-), that is, as the helper/inducer phenotype. The cloned T cells proliferate in response to histoplasmin and, in some cases, to heterologous fungal anigens. Upon injection of mice with the antigen, the T-cells mediate local delayed-type hypersensitivity responses and, after stimulation, release regulatory lymphokines.

  19. Role of T-cells in diabetic pregnancy and macrosomia.

    Science.gov (United States)

    Khan, Naim Akhtar

    2007-10-01

    A number of studies have recently addressed the correlationship between diabetic pregnancy/macrosomia and differentiation of T-cells into Th1 and Th2 subsets. Diabetic pregnancy has been found to be associated with a decreased Th1 phenotype and IL-4 mRNA expression. In macrosomic offspring, high expression of IL-2 and IFN-gamma mRNA, but not of Th2 cytokines is observed, indicating that the Th1 phenotype is upregulated during macrosomia. T-cells of gestational diabetic rats and their macrosomic offspring seem to present a defect in signal transduction. Indeed, the recruitment of free intracellular calcium concentrations from intracellular pool in T-cells of these animals is altered. The phenotype of regulatory T-cells (T-Reg) is upregulated in diabetic pregnancy and their infants. T-cells in diabetic pregnancy and macrosomic obese offspring are in vivo activated. Adipokines and peroxisome proliferator-activated receptor-alpha (PPARalpha) also seem to modulate the pro-inflammatory cytokines in these pathologies. Hence, activation of the immune system might be considered as one of the regulatory pathways including metabolic abnormalities in these two pathologies.

  20. Cord blood CD4+ T cells respond to self heat shock protein 60 (HSP60.

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    Joost A Aalberse

    Full Text Available BACKGROUND: To prevent harmful autoimmunity most immune responses to self proteins are controlled by central and peripheral tolerance. T cells specific for a limited set of self-proteins such as human heat shock protein 60 (HSP60 may contribute to peripheral tolerance. It is not known whether HSP60-specific T cells are present at birth and thus may play a role in neonatal tolerance. We studied whether self-HSP60 reactive T cells are present in cord blood, and if so, what phenotype these cells have. METHODOLOGY/PRINCIPAL FINDINGS: Cord blood mononuclear cells (CBMC of healthy, full term neonates (n = 21, were cultured with HSP60 and Tetanus Toxoid (TT to study antigen specific proliferation, cytokine secretion and up-regulation of surface markers. The functional capacity of HSP60-induced T cells was determined with in vitro suppression assays. Stimulation of CBMC with HSP60 led to CD4(+ T cell proliferation and the production of various cytokines, most notably IL-10, Interferon-gamma, and IL-6. HSP60-induced T cells expressed FOXP3 and suppressed effector T cell responses in vitro. CONCLUSION: Self-reactive HSP60 specific T cells are already present at birth. Upon stimulation with self-HSP60 these cells proliferate, produce cytokines and express FOXP3. These cells function as suppressor cells in vitro and thus they may be involved in the regulation of neonatal immune responses.

  1. CD4+CD25bright T cells in human intestinal lamina propria as regulatory cells.

    Science.gov (United States)

    Makita, Shin; Kanai, Takanori; Oshima, Shigeru; Uraushihara, Koji; Totsuka, Teruji; Sawada, Taisuke; Nakamura, Tetsuya; Koganei, Kazutaka; Fukushima, Tsuneo; Watanabe, Mamoru

    2004-09-01

    It is well known that immune responses in the intestine remain in a state of controlled inflammation, suggesting that not only active suppression by regulatory T cells plays an important role in the normal intestinal homeostasis, but also its dysregulation leads to the development of inflammatory bowel disease. In this study, we demonstrate that the CD4(+)CD25(bright) T cells reside in the human intestinal lamina propria (LP) and functionally retain regulatory activities. All human LP CD4(+) T cells regardless of CD25 expression constitutively expressed CTLA-4, glucocorticoid-induced TNFR family-related protein, and Foxp3 and proliferate poorly. Although LP CD4(+)CD25(-) T cells showed an activated and anergic/memory phenotype, they did not retain regulatory activity. In LP CD4(+)CD25(+) T cells, however, cells expressing CD25 at high levels (CD4(+)CD25(bright)) suppressed the proliferation and various cytokine productions of CD4(+)CD25(-) T cells. LP CD4(+)CD25(bright) T cells by themselves produced fewer amounts of IL-2, IFN-gamma, and IL-10. Interestingly, LP CD4(+)CD25(bright) T cells with regulatory T activity were significantly increased in patients with active inflammatory bowel disease. These results suggest that CD4(+)CD25(bright) T cells found in the normal and inflamed intestinal mucosa selectively inhibit the host immune response and therefore may contribute to the intestinal immune homeostasis. PMID:15322172

  2. Radiosensitivity of CD45RO+ memory and CD45RO- naive T cells in culture

    International Nuclear Information System (INIS)

    Radiosensitivities of various human T-cell subsets were investigated by a proliferation assay and by a single-cell gel electrophoresis assay. Each T-cell subset was purified using a cell sorter and was induced to proliferate by ionomycin and interleukin 2. Unsorted T cells showed biphasic dose-survival curves, indicating the heterogeneity of T cells in terms of radiosensitivity. Purified CD4+ helper and CD8+ killer T cells showed similar biphasic dose-survival curves. Hence both T-cell subsets were composed of cells of different radiosensitivity. The T-cell subsets belonging to different activation stages such as CD45RO+ memory and CD45RO- naive T cells had different dose-survival curves. The former was more radiosensitive than the latter. The high radiosensitivity of CD45RO+ cells was also demonstrated by single-cell gel electrophoresis after irradiation. This is the first demonstration that a particular cell surface marker on T cells is correlated with greater radiosensitivity. 27 refs., 7 figs., 1 tab

  3. Depletion of CD25+CD4+T cells (Tregs) enhances the HBV-specific CD8+ T cell response primed by DNA immunization

    Institute of Scientific and Technical Information of China (English)

    Yoshihiro Furuichi; Hirotake Tokuyama; Satoshi Ueha; Makoto Kurachi; Fuminori Moriyasu; Kazuhiro Kakimi

    2005-01-01

    AIM: Persistent hepatitis B virus (HBV) infection is characterized by a weak CD8+ T cell response to HBV. Immunotherapeutic strategies that overcome tolerance and boost these suboptimal responses may facilitate viral clearance in chronically infected individuals. Therefore, we examined whether CD25+CD4+ regulatory T (Treg) cells might be involved in a inhibition of CD8+T cell priming or in the modulation of the magnitude of the'peak' antiviral CD8+ T cell response primed by DNA immunization. METHODS: B10.D2 mice were immunized once with plasmid pCMV-S. Mice received 500 μg of anti-CD25 mAb injected intraperitoneally 3 d before DNA immunization to deplete CD25+ cells. Induction of HBV-specific CD8+ T ceils in peripheral blood mononuclear cells (PBMCs) was measured by S28-39 peptide loaded DimerX staining and their function was analyzed by intracellular IFN-γ staining.RESULTS: DNA immunization induced HBV-specific CD8+ T cells. At the peak T cell response (d 10), 7.1±2.0% of CD8+ T cells were HBV-specific after DNA immunization, whereas 12.7±3.2% of CD8+ T cells were HBV-specific in Treg-depleted mice, suggesting that DNA immunization induced more antigen-specific CD8+ T cells in the absence of CD25+ Treg cells (n = 6, P<0.05). Similarly, fewer HBVspecific memory T cells were detected in the presence of these cells (1.3±0.4%) in comparison to Treg-depleted mice (2.6±0.9%) on d 30 after DNA immunization (n = 6, P<0.01). Both IFN-γ production and the avidity of the HBV-specific CD8+ T cell response to antigen were higher in HBV-specific CD8+ T cells induced in the absence of Treg cells.CONCLUSION: CD25+ Treg cells suppress priming and/or expansion of antigen-specific CD8+ T cells during DNA immunization and the peak CD8+ T cell response is enhanced by depleting this cell population. Furthermore, Treg cells appear to be involved in the contraction phase of the CD8+ T ceil response and may affect the quality of memory T cell pools. The elimination of Treg

  4. Expression of recombination-activating genes and T cell receptor gene recombination in the human T cell leukemia cell line

    Institute of Scientific and Technical Information of China (English)

    ZOU Hong-yun; MA Li; MENG Min-jie; YAO Xin-sheng; LIN Ying; WU Zhen-qiang; HE Xiao-wei; WANG Ju-fang; WANG Xiao-ning

    2007-01-01

    Background Recent studies have suggested that mature T cells can change their specificity through reexpression of recombination-activating genes (RAG) and RAG-mediated V(D)J recombination. This process is named receptor revision and has been observed in mature peripheral T cells from transgenic mice and human donors. However, whether the receptor revision in mature T cells is a random or orientated process remains poorly understood. Here we used the Jurkat human T cell line, which represents a mature stage of T cell development, as a model to investigate the regulation of T cell receptor (TCR) gene recombination.Methods TCR Dβ-Jβ signal joint T cell receptor excision DNA circles (sjTRECs) were determined by nested and seminested PCR. Double-strand DNA breaks at recombination signal sequences (RSSs) in the TCRVβ chain locus were detected by ligation-mediated-PCR. Further analysis of the complementarity-determining region 3 (CDR3) size of the TCRVβ chain was examined by the TCR GeneScan technique.Results RAG1, RAG2, and three crucial components of the nonhomologous DNA end-joining (NHEJ) pathway were readily detected in Jurkat. Characteristics of junctional diversity of Dβ2-Jβ2 signal joints and ds RSS breaks associated with the Dβ25' and Dβ 23' sites were detected in DNA from Jurkat cells. CDR3 size and the gene sequences of the TCRVβ chain did not change during cell proliferation.Conclusions RAG1 and RAG2 and ongoing TCR gene recombination are coexpressed in Jurkat cells, but the ongoing recombination process may not play a role in modification of the TCR repertoire. However, the results suggest that Jurkat could be used as a model for studying the regulation of RAGs and V(D)J recombination and as a "special" model of the coexistence of TCR gene rearrangements and "negative" receptor revision.

  5. 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.

  6. Human CD141+ DCs induce CD4+ T cells to produce type 2 cytokines1

    Science.gov (United States)

    Yu, Chun I; Becker, Christian; Metang, Patrick; Marches, Florentina; Wang, Yuanyuan; Toshiyuki, Hori; Banchereau, Jacques; Merad, Miriam; Palucka, Karolina

    2014-01-01

    Dendritic cells (DCs) play the central role in the priming of naïve T cells and the differentiation of unique effector T cells. Here, using lung tissues and blood from both humans and humanized mice, we analyzed the response of human CD1c+ and CD141+ DC subsets to live-attenuated influenza virus (LAIV). Specifically, we analyzed the type of CD4+ T cell immunity elicited by LAIV-exposed DCs. Both DC subsets induce proliferation of allogeneic naïve CD4+ T cells with capacity to secrete IFN-γ. However, CD141+ DCs are uniquely able to induce the differentiation of IL-4 and IL-13 producing CD4+ T cells. CD141+ DCs induce IL-4 and IL-13 secreting CD4+ T cells through OX40L. Thus, CD141+ DCs demonstrate remarkable plasticity in guiding adaptive immune responses. PMID:25246496

  7. Novel immunostimulatory effects of osteoclasts and macrophages on human γδ T cells.

    Science.gov (United States)

    Pappalardo, Angela; Thompson, Keith

    2015-02-01

    It has been widely reported that T cells are capable of influencing osteoclast formation and bone remodelling, yet relatively little is known of the reciprocal effects of osteoclasts for affecting T cell function and/or activity. In this study we investigated the effects of human osteoclasts on the function of γδ T cells, a subset of non-CD4(+) T cells implicated in a variety of inflammatory disease states. γδ T cells and CD4(+) T cells were isolated from peripheral blood of healthy volunteers and were co-cultured with autologous mature osteoclasts (generated by treatment with M-CSF and RANKL) before phenotypical and functional changes in the T cell populations were assessed. Macrophages, osteoclasts, and conditioned medium derived from macrophages or osteoclasts induced activation of γδ T cells, as determined by the expression of the early activation marker CD69. TNFα was a major mediator of this stimulatory effect on γδ T cells. Consistent with this stimulatory effect, osteoclasts augmented proliferation of IL-2-stimulated γδ T cells and also supported the survival of unstimulated γδ and CD4(+) T cells, although these effects required co-culture with osteoclasts. Co-culture with osteoclasts also increased the proportion of γδ T cells producing IFNγ, but did not modulate IFNγ or IL-17 production by CD4(+) T cells. We provide new insights into the in vitro interactions between human γδ T cells and osteoclasts/macrophages, and demonstrate that osteoclasts or their precursors are capable of influencing γδ T function both via the release of soluble factors and also through direct cell-cell interactions.

  8. Deletion of Pten in CD45-expressing cells leads to development of T-cell lymphoblastic lymphoma but not myeloid malignancies.

    Science.gov (United States)

    Mirantes, Cristina; Dosil, Maria Alba; Hills, David; Yang, Jian; Eritja, Núria; Santacana, Maria; Gatius, Sònia; Vilardell, Felip; Medvinsky, Alexander; Matias-Guiu, Xavier; Dolcet, Xavier

    2016-04-14

    Since its discovery in the late 1990s, Pten has turned out to be one of the most important tumor suppressor genes. Pten loss results in increased activation of the phosphatidylinositol 3-kinase/Akt signaling pathway, which is associated with increased proliferation, survival, and neoplastic growth. Here, we have addressed the effects of conditional deletion of Pten in hematopoietic cells by crossing Pten conditional knockout mice with a knock-in mouse expressing the Cre recombinase in the CD45 locus. CD45 is also known as leukocyte common antigen, and it is expressed in virtually all white cells and in hematopoietic stem cells. Using a reporter mouse, we demonstrate that CD45:Cre mouse displays recombinase activity in both myeloid and lymphoid cells. However, deletion of Pten in CD45-expressing cells induces development of T-cell acute lymphoblastic leukemia and lymphoma, but not other hematologic malignancies. PMID:26773036

  9. Oral retinoids and rexinoids in cutaneous T-cell lymphomas

    OpenAIRE

    Sokołowska-Wojdyło, Małgorzata; Ługowska-Umer, Hanna; Maciejewska-Radomska, Agata

    2013-01-01

    Retinoids are biologically active derivatives of vitamin A modulating cell proliferation, differentiation, apoptosis and altering the immune response. They have been used for years in therapy of cutaneous T-cell lymphomas (CTCL) but the exact mechanism of retinoids’ action is unclear. It is based on the presence of specific receptors’ families, mediating the biological effects of retinoids on the tumor cells: retinoic acid receptor (RAR) and retinoic X receptor (RXR). Orally administrated bex...

  10. Cytotoxicity of tumor antigen specific human T cells is unimpaired by arginine depletion.

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    Markus Munder

    Full Text Available Tumor-growth is often associated with the expansion of myeloid derived suppressor cells that lead to local or systemic arginine depletion via the enzyme arginase. It is generally assumed that this arginine deficiency induces a global shut-down of T cell activation with ensuing tumor immune escape. While the impact of arginine depletion on polyclonal T cell proliferation and cytokine secretion is well documented, its influence on chemotaxis, cytotoxicity and antigen specific activation of human T cells has not been demonstrated so far. We show here that chemotaxis and early calcium signaling of human T cells are unimpaired in the absence of arginine. We then analyzed CD8(+ T cell activation in a tumor peptide as well as a viral peptide antigen specific system: (i CD8(+ T cells with specificity against the MART-1aa26-35*A27L tumor antigen expanded with in vitro generated dendritic cells, and (ii clonal CMV pp65aa495-503 specific T cells and T cells retrovirally transduced with a CMV pp65aa495-503 specific T cell receptor were analyzed. Our data demonstrate that human CD8(+ T cell antigen specific cytotoxicity and perforin secretion are completely preserved in the absence of arginine, while antigen specific proliferation as well as IFN-γ and granzyme B secretion are severely compromised. These novel results highlight the complexity of antigen specific T cell activation and demonstrate that human T cells can preserve important activation-induced effector functions in the context of arginine deficiency.

  11. Human T cells express CD25 and Foxp3 upon activation and exhibit effector/memory phenotypes without any regulatory/suppressor function

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    Godder Kamar

    2009-10-01

    Full Text Available Abstract Background Foxp3 has been suggested to be a standard marker for murine Tregs whereas its role as marker for human Tregs is controversial. While some reports have shown that human Foxp3+ T cells had no regulatory function others have shown their role in the inhibition of T cell proliferation. Methods T cell activation was performed by means of brayostatin-1/ionomycin (B/I, mixed lymphocyte reaction (MLR, and CD3/CD28 activation. T cell proliferation was performed using BrdU and CFSE staining. Flow cytometry was performed to determine Foxp3 expression, cell proliferation, viabilities and phenotype analyses of T cells. Results Both CD4+ and CD8+ T cells expressed Foxp3 upon activation in vitro. Expression of Foxp3 remained more stable in CD4+CD25+ T cells compared to that in CD8+CD25+ T cells. The CD4+CD25+Foxp3+ T cells expressed CD44 and CD62L, showing their effector and memory phenotypes. Both FoxP3- responder T cells and CD4+FoxP3+ T cells underwent proliferation upon CD3/CD28 activation. Conclusion Expression of Foxp3 does not necessarily convey regulatory function in human CD4+CD25+ T cells. Increased FoxP3 on CD44+ effector and CD44+CD62L+ memory T cells upon stimulation suggest the activation-induced regulation of FoxP3 expression.

  12. Interferon-Beta Therapy of Multiple Sclerosis Patients Improves the Responsiveness of T Cells for Immune Suppression by Regulatory T Cells

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    Bettina Trinschek

    2015-07-01

    Full Text Available Multiple sclerosis (MS is an inflammatory autoimmune disease characterized by imbalanced immune regulatory networks, and MS patient-derived T effector cells are inefficiently suppressed through regulatory T cells (Treg, a phenomenon known as Treg resistance. In the current study we investigated T cell function in MS patients before and after interferon-beta therapy. We compared cytokine profile, responsiveness for Treg-mediated suppression ex vivo and evaluated reactivity of T cells in vivo using a humanized mouse model. We found that CD4+ and CD8+ T cells of therapy-naive MS patients were resistant to Treg-mediated suppression. Treg resistance is associated with an augmented IL-6 production, enhanced IL-6 receptor expression, and increased PKB/c-Akt phosphorylation. These parameters as well as responsiveness of T cells to Treg-mediated suppression were restored after interferon-beta therapy of MS patients. Following transfer into immunodeficient mice, MS T cells induced a lethal graft versus host disease (GvHD and in contrast to T cells of healthy volunteers, this aggressive T cell response could not be controlled by Treg, but was abolished by anti-IL-6 receptor antibodies. However, magnitude and lethality of GvHD induced by MS T cells was significantly decreased after interferon-beta therapy and the reaction was prevented by Treg activation in vivo. Our data reveals that interferon-beta therapy improves the immunoregulation of autoaggressive T effector cells in MS patients by changing the IL-6 signal transduction pathway, thus restoring their sensitivity to Treg-mediated suppression.

  13. Qualitative and quantitative analysis of adenovirus type 5 vector-induced memory CD8 T cells

    DEFF Research Database (Denmark)

    Steffensen, Maria Abildgaard; Holst, Peter Johannes; Steengaard, Sanne Skovvang;

    2013-01-01

    It has been reported that adenovirus (Ad) primed CD8 T cells may display a distinct and partially exhausted phenotype. Given the practical implications of this claim, we decided to analyze in detail the quality of Ad-primed CD8 T cells directly comparing these cells to CD8 T cells induced through...... adenoviral boosting and, importantly, the generated secondary memory cells cannot be qualitatively differentiated from those induced by primary infection with replicating virus. Quantitatively, DNA priming prior to Ad-vaccination will lead to even higher numbers of memory cells. In this case, the vaccination...... an effective means to induce a substantially expanded, long-lived population of high-quality transgene-specific memory CD8 T cells....

  14. Metabolic reprogramming towards aerobic glycolysis correlates with greater proliferative ability and resistance to metabolic inhibition in CD8 versus CD4 T cells.

    Directory of Open Access Journals (Sweden)

    Yilin Cao

    Full Text Available T lymphocytes (T cells undergo metabolic reprogramming after activation to provide energy and biosynthetic materials for growth, proliferation and differentiation. Distinct T cell subsets, however, adopt metabolic programs specific to support their needs. As CD4 T cells coordinate adaptive immune responses while CD8 T cells become cytotoxic effectors, we compared activation-induced proliferation and metabolic reprogramming of these subsets. Resting CD4 and CD8 T cells were metabolically similar and used a predominantly oxidative metabolism. Following activation CD8 T cells proliferated more rapidly. Stimulation led both CD4 and CD8 T cells to sharply increase glucose metabolism and adopt aerobic glycolysis as a primary metabolic program. Activated CD4 T cells, however, remained more oxidative and had greater maximal respiratory capacity than activated CD8 T cells. CD4 T cells were also associated with greater levels of ROS and increased mitochondrial content, irrespective of the activation context. CD8 cells were better able, however, to oxidize glutamine as an alternative fuel source. The more glycolytic metabolism of activated CD8 T cells correlated with increased capacity for growth and proliferation, along with reduced sensitivity of cell growth to metabolic inhibition. These specific metabolic programs may promote greater growth and proliferation of CD8 T cells and enhance survival in diverse nutrient conditions.

  15. PD-L1-specific T cells

    DEFF Research Database (Denmark)

    Ahmad, Shamaila Munir; Borch, Troels Holz; Hansen, Morten;

    2016-01-01

    -specific T cells that recognize both PD-L1-expressing immune cells and malignant cells. Thus, PD-L1-specific T cells have the ability to modulate adaptive immune reactions by reacting to regulatory cells. Thus, utilization of PD-L1-derived T cell epitopes may represent an attractive vaccination strategy...... for targeting the tumor microenvironment and for boosting the clinical effects of additional anticancer immunotherapy. This review summarizes present information about PD-L1 as a T cell antigen, depicts the initial findings about the function of PD-L1-specific T cells in the adjustment of immune responses...

  16. Direct inhibition of T-cell responses by the Cryptococcus capsular polysaccharide glucuronoxylomannan.

    Directory of Open Access Journals (Sweden)

    Lauren E Yauch

    2006-11-01

    Full Text Available The major virulence factor of the pathogenic fungi Cryptococcus neoformans and C. gattii is the capsule. Glucuronoxylomannan (GXM, the major component of the capsule, is a high-molecular-weight polysaccharide that is shed during cryptococcosis and can persist in patients after successful antifungal therapy. Due to the importance of T cells in the anticryptococcal response, we studied the effect of GXM on the ability of dendritic cells (DCs to initiate a T-cell response. GXM inhibited the activation of cryptococcal mannoprotein-specific hybridoma T cells and the proliferation of OVA-specific OT-II T cells when murine bone marrow-derived DCs were used as antigen-presenting cells. Inhibition of OT-II T-cell proliferation was observed when either OVA protein or OVA323-339 peptide was used as antigen, indicating GXM did not merely prevent antigen uptake or processing. We found that DCs internalize GXM progressively over time; however, the suppressive effect did not require DCs, as GXM directly inhibited T-cell proliferation induced by anti-CD3 antibody, concanavalin A, or phorbol-12-myristate-13-acetate/ionomycin. Analysis of T-cell viability revealed that the reduced proliferation in the presence of GXM was not the result of increased cell death. GXM isolated from each of the four major cryptococcal serotypes inhibited the proliferation of human peripheral blood mononuclear cells stimulated with tetanus toxoid. Thus, we have defined a new mechanism by which GXM can impart virulence: direct inhibition of T-cell proliferation. In patients with cryptococcosis, this could impair optimal cell-mediated immune responses, thereby contributing to the persistence of cryptococcal infections.

  17. The role of Protein Kinase Cη in T cell biology

    Directory of Open Access Journals (Sweden)

    Nicholas R.J. Gascoigne

    2012-06-01

    Full Text Available Protein kinase Cη (PKCη is a member of the novel PKC subfamily, which also includes δ, ε, and θ isoforms. Compared to the other novel PKCs, the function of PKCη in the immune system is largely unknown. Several studies have started to reveal the role of PKCη, particularly in T cells. PKCη is highly expressed in T cells, and is upregulated during thymocyte positive selection. Interestingly, like the θ isoform, PKCη is also recruited to the immunological synapse that is formed between a T cell and an antigen-presenting cell. However, unlike PKCθ, which becomes concentrated to the central region of the synapse, PKCη remains in a diffuse pattern over the whole area of the synapse, suggesting distinctive roles of these two isoforms in signal transduction. Although PKCη is dispensable for thymocyte development, further analysis of PKCη− or PKCθ−deficient and double knockout mice revealed the redundancy of these two isoforms in thymocyte development. In contrast, PKCη rather than PKCθ, plays an important role for T cell homeostatic proliferation, which requires recognition of self-antigen. Another piece of evidence demonstrating that PKCη and PKCθ have isoform specific as well as redundant roles come from the analysis of CD4 to CD8 T cell ratios in the periphery of these knockout mice. Deficiency in PKCη or PKCθ had opposing effects as PKCη knockout mice had a higher ratio of CD4 to CD8 T cells compared to that of wild-type mice, whereas PKCθ-deficient mice had a lower ratio. Biochemical studies showed that calcium flux and NFκB translocation is impaired in PKCη-deficient T cells upon TCR crosslinking stimulation, a character shared with PKCθ-deficient T cells. However, unlike the case with PKCθ, the mechanistic study of PKCη is at early stage and the signaling pathways involving PKCη, at least in T cells, are essentially unknown. In this review, we will cover the topics mentioned above as well as provide some

  18. Regulatory T cells as immunotherapy

    Directory of Open Access Journals (Sweden)

    Benjamin David Singer

    2014-02-01

    Full Text Available Regulatory T cells (Tregs suppress exuberant immune system activation and promote immunologic tolerance. Because Tregs modulate both innate and adaptive immunity, the biomedical community has developed intense interest in using Tregs for immunotherapy. Conditions that require clinical tolerance to improve outcomes—autoimmune disease, solid organ transplantation, and hematopoietic stem cell transplantation—may benefit from Treg immunotherapy. Investigators have designed ex vivo strategies to isolate, preserve, expand, and infuse Tregs. Protocols to manipulate Treg populations in vivo have also been considered. Barriers to clinically feasible Treg immunotherapy include Treg stability, off-cell effects, and demonstration of cell preparation purity and potency. Clinical trials involving Treg adoptive transfer to treat graft versus host disease preliminarily demonstrated the safety and efficacy of Treg immunotherapy in humans. Future work will need to confirm the safety of Treg immunotherapy and establish the efficacy of specific Treg subsets for the treatment of immune-mediated disease.

  19. A virtual lymph node model to dissect the requirements for T-cell activation by synapses and kinapses

    Science.gov (United States)

    Moreau, Hélène D; Bogle, Gib; Bousso, Philippe

    2016-01-01

    The initiation of T-cell responses in lymph nodes requires T cells to integrate signals delivered by dendritic cells (DCs) during long-lasting contacts (synapses) or more transient interactions (kinapses). However, it remains extremely challenging to understand how a specific sequence of contacts established by T cells ultimately dictates T-cell fate. Here, we have coupled a computational model of T-cell migration and interactions with DCs with a real-time, flow cytometry-like representation of T-cell activation. In this model, low-affinity peptides trigger T-cell proliferation through kinapses but we show that this process is only effective under conditions of high DC densities and prolonged antigen availability. By contrast, high-affinity peptides favor synapse formation and a vigorous proliferation under a wide range of antigen presentation conditions. In line with the predictions, decreasing the DC density in vivo selectively abolished proliferation induced by the low-affinity peptide. Finally, our results suggest that T cells possess a biochemical memory of previous stimulations of at least 1–2 days. We propose that the stability of T-cell–DC interactions, apart from their signaling potency, profoundly influences the robustness of T-cell activation. By offering the ability to control parameters that are difficult to manipulate experimentally, the virtual lymph node model provides new possibilities to tackle the fundamental mechanisms that regulate T-cell responses elicited by infections or vaccines. PMID:27089942

  20. Cholesterol lowering modulates T cell function in vivo and in vitro.

    Directory of Open Access Journals (Sweden)

    Kuang-Yuh Chyu

    Full Text Available The lipid milleu exacerbates the inflammatory response in atherosclerosis but its effect on T cell mediated immune response has not been fully elucidated. We hypothesized that lipid lowering would modulate T cell mediated immune function.T cells isolated from human PBMC or splenic T cells from apoE-/- mouse had higher proliferative response to T cell receptor (TCR ligation in medium supplemented with 10% fetal bovine serum (FBS compared to medium with 10% delipidated FBS. The differences in proliferation were associated with changes in lipid rafts, cellular cholesterol content, IL-10 secretion and subsequent activation of signaling molecule activated by TCR ligation. Immune biomarkers were also assessed in vivo using male apoE-/- mice fed atherogenic diet (AD starting at 7 weeks of age. At 25 weeks of age, a sub-group was switched to normal diet (ND whereas the rest remained on AD until euthanasia at 29 weeks of age. Dietary change resulted in a lower circulating level of cholesterol, reduced plaque size and inflammatory phenotype of plaques. These changes were associated with reduced intracellular IL-10 and IL-12 expression in CD4+ and CD8+ T cells.Our results show that lipid lowering reduces T cell proliferation and function, supporting the notion that lipid lowering modulates T cell function in vivo and in vitro.

  1. The aged lymphoid tissue environment fails to support naïve T cell homeostasis.

    Science.gov (United States)

    Becklund, Bryan R; Purton, Jared F; Ramsey, Chris; Favre, Stéphanie; Vogt, Tobias K; Martin, Christopher E; Spasova, Darina S; Sarkisyan, Gor; LeRoy, Eric; Tan, Joyce T; Wahlus, Heidi; Bondi-Boyd, Brea; Luther, Sanjiv A; Surh, Charles D

    2016-01-01

    Aging is associated with a gradual loss of naïve T cells and a reciprocal increase in the proportion of memory T cells. While reduced thymic output is important, age-dependent changes in factors supporting naïve T cells homeostasis may also be involved. Indeed, we noted a dramatic decrease in the ability of aged mice to support survival and homeostatic proliferation of naïve T cells. The defect was not due to a reduction in IL-7 expression, but from a combination of changes in the secondary lymphoid environment that impaired naïve T cell entry and access to key survival factors. We observed an age-related shift in the expression of homing chemokines and structural deterioration of the stromal network in T cell zones. Treatment with IL-7/mAb complexes can restore naïve T cell homeostatic proliferation in aged mice. Our data suggests that homeostatic mechanisms that support the naïve T cell pool deteriorate with age.

  2. Long-term kinetics of T cell production in HIV-infected subjects treated with highly active antiretroviral therapy

    Science.gov (United States)

    Fleury, S.; Rizzardi, G. P.; Chapuis, A.; Tambussi, G.; Knabenhans, C.; Simeoni, E.; Meuwly, J.-Y.; Corpataux, J.-M.; Lazzarin, A.; Miedema, F.; Pantaleo, G.

    2000-01-01

    The long-term kinetics of T cell production following highly active antiretroviral therapy (HAART) were investigated in blood and lymph node in a group of HIV-infected subjects at early stage of established infection and prospectively studied for 72 wk. Before HAART, CD4 and CD8 T cell turnover was increased. However, the total number of proliferating CD4+ T lymphocytes, i.e., CD4+Ki67+ T lymphocytes, was not significantly different in HIV-infected (n = 73) and HIV-negative (n = 15) subjects, whereas proliferating CD8+Ki67+ T lymphocytes were significantly higher in HIV-infected subjects. After HAART, the total body number of proliferating CD4+Ki67+ T lymphocytes increased over time and was associated with an increase of both naive and memory CD4+ T cells. The maximal increase (2-fold) was observed at week 36, whereas at week 72 the number of proliferating CD4+ T cells dropped to baseline levels, i.e., before HAART. The kinetics of the fraction of proliferating CD4 and CD8 T cells were significantly correlated with the changes in the total body number of these T cell subsets. These results demonstrate a direct relationship between ex vivo measures of T cell production and quantitative changes in total body T lymphocyte populations. This study provides advances in the delineation of the kinetics of T cell production in HIV infection in the presence and/or in the absence of HAART. PMID:10805798

  3. Phospholipase C-gamma 1 association with CD3 structure in T cells

    OpenAIRE

    1992-01-01

    Recently, we and others have reported tyrosine phosphorylation of phospholipase C-gamma 1 (PLC gamma 1) enzyme after CD3 activation of T cells, and have proposed that PLC gamma 1 mediates signal transduction through the T cell receptor (TCR/CD3). Here, using immunoblotting and immune complex PLC assays, we show that CD3 stimulation of Jurkat cells induces the association of PLC gamma 1 enzyme with CD3 complex. PLC activity is also found to co-precipitate with the CD3 zeta chain from activated...

  4. Circadian control of antigen-specific T cell responses

    Directory of Open Access Journals (Sweden)

    Nobis CC

    2016-09-01

    Full Text Available Chloé C Nobis,1–3 Nathalie Labrecque,2–4 Nicolas Cermakian1,5–8 1Douglas Mental Health University Institute, 2Maisonneuve-Rosemont Hospital Research Centre, 3Department of Microbiology, Infectious Diseases and Immunology, 4Department of Medicine, University of Montreal, 5Department of Psychiatry, 6Department of Microbiology and Immunology, 7Department of Neurology and Neurosurgery, 8Department of Physiology, McGill University, Montreal, QC, Canada Abstract: The immune system is composed of two arms, the innate and the adaptive immunity. While the innate response constitutes the first line of defense and is not specific for a particular pathogen, the adaptive response is highly specific and allows for long-term memory of the pathogen encounter. T lymphocytes (or T cells are central players in the adaptive immune response. Various aspects of T cell functions vary according to the time of day. Circadian clocks located in most tissues and cell types generate 24-hour rhythms of various physiological processes. These clocks are based on a set of clock genes, and this timing mechanism controls rhythmically the expression of numerous other genes. Clock genes are expressed in cells of the immune system, including T cells. In this review, we provide an overview of the circadian control of the adaptive immune response, with emphasis on T cells, including their development, trafficking, response to antigen, and effector functions. Keywords: circadian clock, adaptive immune response, T lymphocyte, antigen, cytokine, proliferation

  5. Identification of novel Notch target genes in T cell leukaemia

    Directory of Open Access Journals (Sweden)

    Warrander Fiona

    2009-06-01

    Full Text Available Abstract Background Dysregulated Notch signalling is believed to play an important role in the development and maintenance of T cell leukaemia. At a cellular level, Notch signalling promotes proliferation and inhibits apoptosis of T cell acute lymphoblastic leukaemia (T-ALL cells. In this study we aimed to identify novel transcriptional targets of Notch signalling in the T-ALL cell line, Jurkat. Results RNA was prepared from Jurkat cells retrovirally transduced with an empty vector (GFP-alone or vectors containing constitutively active forms of Notch (N1ΔE or N3ΔE, and used for Affymetrix microarray analysis. A subset of genes found to be regulated by Notch was chosen for real-time PCR validation and in some cases, validation at the protein level, using several Notch-transduced T-ALL and non-T-ALL leukaemic cell lines. As expected, several known transcriptional target of Notch, such as HES1 and Deltex, were found to be overexpressed in Notch-transduced cells, however, many novel transcriptional targets of Notch signalling were identified using this approach. These included the T cell costimulatory molecule CD28, the anti-apoptotic protein GIMAP5, and inhibitor of DNA binding 1 (1D1. Conclusion The identification of such downstream Notch target genes provides insights into the mechanisms of Notch function in T cell leukaemia, and may help identify novel therapeutic targets in this disease.

  6. Mast cells as regulators of T cell responses

    Directory of Open Access Journals (Sweden)

    Silvia eBulfone-Paus

    2015-08-01

    Full Text Available Mast cells are recognized to participate in the regulation of innate and adaptive immune responses. Owing to their strategic location at the host-environment interface they control tissue homeostasis and are key cells for starting early host defence against intruders. Upon degranulation induced, e.g. by immunoglobulin E (IgE and allergen-mediated engagement of the high-affinity IgE receptor, complement or certain neuropeptide receptors, mast cells release a wide variety of preformed and newly synthesized products including proteases, lipid mediators, and many cytokines, chemokines, and growth factors. Interestingly, increasing evidence suggests a regulatory role for mast cells in inflammatory diseases via the regulation of T cell activities. Furthermore, rather than only serving as effector cells, mast cells are now recognized to induce T cell activation, recruitment, proliferation and cytokine secretion in an antigen-dependent manner and to impact on regulatory T cells. This review synthesizes recent developments in mast cell-T cell interactions, discusses their biological and clinical relevance, and explores recent controversies in this field of mast cell research.

  7. Synthetic Peptide libraries for T-cell epitope identification.

    Science.gov (United States)

    Hiemstra, H S; Drijfhout, J W; Koning, F

    2000-01-01

    This chapter describes a methodology for elucidating immunogenic epitopes stimulatory for CD4(+) T-cell clones (Fig. 1). The methodology makes use of synthetic peptide libraries and must be regarded as an alternative to other approaches, such as peptide elution or the application of genetic libraries. The methodology only requires knowledge about the restriction element of the T-cell clone. The restriction element determines which major histocompatibility complex (MHC)-binding anchor motif must be built into the library peptides. A synthetic peptide library is prepared comprising approx 8 million peptides. The synthesis proceeds via a mix-and-split protocol using a solidphase approach on a hybrid resin (1,2). On a hybrid resin, most of the peptide material (84%) is attached via an acid-labile linker whereas the remaining part of the peptide material is acid-stable attached (3). During synthesis, resinbound peptides comprising 14 amino acid residues are produced, with each resin bead containing one unique peptide (4,5). The beads are split into 384 pools, with each pool containing 20,000 beads. From each pool, about 28% of the peptide material is cleaved from every bead. Subsequently, in the first screening round, the 384 pools, each containing 20,000 solubilized peptides, are tested in a proliferation assay with the T-cell clone. Fig. 1. Flow diagram of the complete procedure for the identification of T-cell epitopes using synthetic peptide libraries (1).

  8. 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.

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

    Science.gov (United States)

    Golubovskaya, Vita; Wu, Lijun

    2016-01-01

    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.

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

    Science.gov (United States)

    Golubovskaya, Vita; Wu, Lijun

    2016-01-01

    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. PMID:26999211

  11. Cutting edge: T cells respond to lipopolysaccharide innately via TLR4 signaling.

    Science.gov (United States)

    Zanin-Zhorov, Alexandra; Tal-Lapidot, Guy; Cahalon, Liora; Cohen-Sfady, Michal; Pevsner-Fischer, Meirav; Lider, Ofer; Cohen, Irun R

    2007-07-01

    LPS, a molecule produced by Gram-negative bacteria, is known to activate both innate immune cells such as macrophages and adaptive immune B cells via TLR4 signaling. Although TLR4 is also expressed on T cells, LPS was observed not to affect T cell proliferation or cytokine secretion. We now report, however, that LPS can induce human T cells to adhere to fibronectin via TLR4 signaling. This response to LPS was confirmed in mouse T cells; functional TLR4 and MyD88 were required, but T cells from TLR2 knockout mice could respond to LPS. The human T cell response to LPS depended on protein kinase C signaling and involved the phosphorylation of the proline-rich tyrosine kinase (Pyk-2) and p38. LPS also up-regulated the T cell expression of suppressor of cytokine signaling 3, which led to inhibition of T cell chemotaxis toward the chemokine stromal cell-derived factor 1alpha (CXCL12). Thus, LPS, through TLR4 signaling, can affect T cell behavior in inflammation. PMID:17579019

  12. Effect of rapamycin and ciclosporin on proliferation of human periheral blood CD4+CD2+5 regulatory T cells%雷帕霉素及环孢素对人类外周血 CD4+CD2+5调节性T细胞体外增殖的影响

    Institute of Scientific and Technical Information of China (English)

    赵冰清; 朱志军; 王永磊

    2015-01-01

    Objective To observe the influence of rapamycin and ciclosporin on the proliferation of human periheral blood CD4+CD2+5 regulatory T cells.Methods The CD4+CD2+5 regulatory T cells ( Treg cells) from human peripheral blood were isolated by immunomagnetic bead separation, the purity of CD4+CD2+5 Treg was measured by flow cytometry.We divid-ed the CD4+CD2+5 Treg into the groups A, B and C, which were added with 100 nmol/L rapamycin, 410 nmol/L cyclospo-rine and the blank culture medium.After 7 days′culture, we calculated the percentage of primary Treg cells of different groups by flow cytometry.Results The percentage of primary Treg cells in the groups A, B and C were 8.8%±3.2%, 48.9%±7.0%and 33.2%±4.3%, respectively.Significant difference was found when we compared groups A and B with group C, respectively ( all P <0.05).Conclusion Rapamycin can significantly promote the proliferation of CD4+CD2+5 Treg in vitro, and it promotes the formation of immune tolerance in patients after transplantation;but cyclosporine inhibits the proliferation of CD4+CD2+5 Treg and hampers the progression.%目的:观察雷帕霉素与环孢素对人类外周血CD4+CD2+5调节性T细胞( Treg)体外增殖的影响。方法利用免疫磁珠法提取健康成人外周血CD4+CD2+5 Treg,流式细胞仪检测CD4+CD2+5 Treg纯度;将羧基荧光素乙酰乙酸进行标记的CD4+CD2+5 Treg分为A、B、C组,分别加入100 nmol/L雷帕霉素、410 nmol/L环孢素及空白培养基;培养7 d后上流式细胞仪,计算原代细胞所占比例。结果 A组原代细胞所占比例为8.8%±3.2%,B组为48.9%±7.0%,C组为33.2%±4.3%;A、B组分别与C组比较,P均<0.05。结论雷帕霉素可促进CD4+CD2+5 Treg的体外增殖,有利于移植后患者免疫耐受的形成;而环孢素则抑制CD4+CD2+5 Treg的体外增殖,不利于免疫耐受的形成。

  13. T cell migration, search strategies and mechanisms.

    Science.gov (United States)

    Krummel, Matthew F; Bartumeus, Frederic; Gérard, Audrey

    2016-03-01

    T cell migration is essential for T cell responses; it allows for the detection of cognate antigen at the surface of antigen-presenting cells and for interactions with other cells involved in the immune response. Although appearing random, growing evidence suggests that T cell motility patterns are strategic and governed by mechanisms that are optimized for both the activation stage of the cell and for environment-specific cues. In this Opinion article, we discuss how the combined effects of T cell-intrinsic and -extrinsic forces influence T cell motility patterns in the context of highly complex tissues that are filled with other cells involved in parallel motility. In particular, we examine how insights from 'search theory' can be used to describe T cell movement across an 'exploitation-exploration trade-off' in the context of activation versus effector function and lymph nodes versus peripheral tissues. PMID:26852928

  14. Shock waves co-stimulate T-cell proliferation and interleukin-2 expression through ATP release, P2 receptor and p38 mitogen activated protein kinase activation%冲击波通过ATP释放、P2受体及激活p38MAPK激酶促进T细胞增殖和分泌白细胞介素2

    Institute of Scientific and Technical Information of China (English)

    于铁成; 赵毅; 陈玮伦; 金安; 刘建国

    2007-01-01

    的ATP的含量明显增加(P<0.01),并且ATP的增加含量和冲击波的作用次数有依从关系.②加入apyrase,KN-62,suramin的植物血凝素激活的外周血单个核细胞细胞或CD3和CD28激活的Jurkat T细胞,在能量密度为0.18 mJ/mm2的冲击波作用100,150,200,250,300,330次时,细胞对3H-TdR掺入量比没有加入apyrase、KN-62或suramin的阴性对照组低(P<0.01),细胞上清液中的的细胞介素-2的活性含量表现为明显增高(P<0.01).加入ATP、KN-62或suramin后,冲击波激活Jurkat T细胞的p38 MAPK的程度明显降低.结论:①低能冲击波能损伤细胞膜而不损伤其他细胞器,引起T淋巴细胞内的ATP过多向细胞外分泌,细胞外过量的ATP过多地激活了P2X7受体,激活细胞内的大量的p38 MAPK,最后磷酸化的p38MAPK作为协同刺激因子增强激活的T淋巴细胞增殖及分泌白细胞介素2.②在低能冲击波对T淋巴细胞的功能调节上,T细胞分泌的ATP起到非常重要的作用.%BACKGROUND:The previous researches indicate that, shock waves can enhance the proliferation of T-cells and the expression of interleukin (IL)-2 through a mechanism that involves p38 mitogen activated protein kinase (MAPK)activation.OBJECTIVE: To investigate if adenosine triphosphate (ATP) release is an underlying mechanism through which low-density shock waves (LDSWs) augment T-cell function.DESIGN: Controlled repetitive measurement by groups, taking cells as subject.SETTING: Department of Orthopedics, the First Hospital of Jilin University.MATERIALS: KDE-2001 Extracorporeal Shockwave Lithotripter (Beijing Zhongke Jian An Meditechs Co., Beijing, China).p38 MAPK inhibitor SB203580 1 mg (BioSource Inc., Camarillo, CA); p38 MAPK kit for detecting phosphorylation (Cell Signaling Technology, Inc. U.S.A.); P2 receptor inhibitor suramin 50 mg (BIOMOL Research Laboratories Inc., PA) was prepared into 0.02 mol/L solution by 1.749 2 mL IMDM. ATP enzyme: apyrase 200 U (Sigma, U.S.A.); P2X7 receptor antagonist KN-62 (Bio

  15. 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.

  16. Drak2 Does Not Regulate TGF-β Signaling in T Cells.

    Directory of Open Access Journals (Sweden)

    Tarsha L Harris

    Full Text Available Drak2 is a serine/threonine kinase expressed highest in T cells and B cells. Drak2-/- mice are resistant to autoimmunity in mouse models of type 1 diabetes and multiple sclerosis. Resistance to these diseases occurs, in part, because Drak2 is required for the survival of autoreactive T cells that induce disease. However, the molecular mechanisms by which Drak2 affects T cell survival and autoimmunity are not known. A recent report demonstrated that Drak2 negatively regulated transforming growth factor-β (TGF-β signaling in tumor cell lines. Thus, increased TGF-β signaling in the absence of Drak2 may contribute to the resistance to autoimmunity in Drak2-/- mice. Therefore, we examined if Drak2 functioned as a negative regulator of TGF-β signaling in T cells, and whether the enhanced susceptibility to death of Drak2-/- T cells was due to augmented TGF-β signaling. Using several in vitro assays to test TGF-β signaling and T cell function, we found that activation of Smad2 and Smad3, which are downstream of the TGF-β receptor, was similar between wildtype and Drak2-/- T cells. Furthermore, TGF-β-mediated effects on naïve T cell proliferation, activated CD8+ T cell survival, and regulatory T cell induction was similar between wildtype and Drak2-/- T cells. Finally, the increased susceptibility to death in the absence of Drak2 was not due to enhanced TGF-β signaling. Together, these data suggest that Drak2 does not function as a negative regulator of TGF-β signaling in primary T cells stimulated in vitro. It is important to investigate and discern potential molecular mechanisms by which Drak2 functions in order to better understand the etiology of autoimmune diseases, as well as to validate the use of Drak2 as a target for therapeutic treatment of these diseases.

  17. Glucose Uptake Is Limiting in T Cell Activation and Requires CD28-Mediated Akt-Dependent and Independent Pathways1

    OpenAIRE

    Jacobs, Sarah R.; Herman, Catherine E.; MacIver, Nancie J.; Wofford, Jessica A.; Wieman, Heather L.; Hammen, Jeremy J.; Rathmell, Jeffrey C.

    2008-01-01

    T cell activation potently stimulates cellular metabolism to support the elevated energetic and biosynthetic demands of growth, proliferation, and effector function. We show that glucose uptake is limiting in T cell activation and that CD28 costimulation is required to allow maximal glucose uptake following TCR stimulation by up-regulating expression and promoting the cell surface trafficking of the glucose transporter Glut1. Regulation of T cell glucose uptake and Glut1 was critical, as low ...

  18. Anaplerotic Metabolism of Alloreactive T Cells Provides a Metabolic Approach To Treat Graft-Versus-Host Disease

    OpenAIRE

    Glick, Gary D.; Rossignol, Rodrigue; Lyssiotis, Costas A.; Wahl, Daniel; Lesch, Charles; Sanchez, Brian; Liu, Xikui; Hao, Ling-Yang; Taylor, Clarke; Hurd, Alexander; Ferrara, James L. M.; Tkachev, Victor; Byersdorfer, Craig A.; Boros, Laszlo; Opipari, Anthony W.

    2014-01-01

    T-cell activation requires increased ATP and biosynthesis to support proliferation and effector function. Most models of T-cell activation are based on in vitro culture systems and posit that aerobic glycolysis is employed to meet increased energetic and biosynthetic demands. By contrast, T cells activated in vivo by alloantigens in graft-versus-host disease (GVHD) increase mitochondrial oxygen consumption, fatty acid uptake, and oxidation, with small increases of glucose uptake and aerobic g...

  19. T cell homeostasis requires G protein-coupled receptor-mediated access to trophic signals that promote growth and inhibit chemotaxis

    OpenAIRE

    Cinalli, Ryan M.; Herman, Catherine E.; Lew, Brian O.; Wieman, Heather L.; Thompson, Craig B.; Rathmell, Jeffrey C.

    2005-01-01

    Signals that regulate T cell homeostasis are not fully understood. G protein-coupled receptors (GPCR), such as the chemokine receptors, may affect homeostasis by direct signaling or by guiding T cell migration to distinct location-restricted signals. Here, we show that blockade of Gαi-associated GPCR signaling by treatment with pertussis toxin led to T cell atrophy and shortened life-span in T cell-replete hosts and prevented T cell homeostatic growth and proliferation in T cell-deficient hos...

  20. Apoptosis following interleukin-2 withdrawal from T cells: evidence for a regulatory role of CD18 (beta 2-integrin) molecules

    DEFF Research Database (Denmark)

    Röpke, C; Gladstone, P; Nielsen, M;

    1996-01-01

    induce an enhanced apoptotic responses in LFA-1 negative T cells, and, reversely, culture supernatants from LFA-1 negative T cells did not rescue LFA-1 positive cells from undergoing apoptosis. The apoptotic response was partly blocked by IL-15, a newly identified T cell growth factor. Taken together......Following a successful immune response against invading microorganisms, the majority of activated T cells is eliminated, while a minor fraction survives as memory T cells. A decline in T lymphocyte growth factors such as interleukin-2 (IL-2) appears to play a role in the elimination of previously...... activated T cells. Thus, removal of IL-2 from proliferating T cells not only induces growth arrest, but triggers a massive cell death due to apoptosis. While the apoptotic response involves a series of well-described events, it remains less clear how apoptosis is regulated following IL-2 withdrawal. Here...

  1. CXCR3 Directs Antigen-Specific Effector CD4+ T Cell Migration to the Lung During Parainfluenza Virus Infection

    DEFF Research Database (Denmark)

    Kohlmeier, Jacob E; Cookenham, Tres; Miller, Shannon C;

    2009-01-01

    Effector T cells are a crucial component of the adaptive immune response to respiratory virus infections. Although it was previously reported that the chemokine receptors CCR5 and CXCR3 affect trafficking of respiratory virus-specific CD8(+) T cells, it is unclear whether these receptors govern...... effector CD4(+) T cell migration to the lungs. To assess the role of CCR5 and CXCR3 in vivo, we directly compared the migration of Ag-specific wild-type and chemokine receptor-deficient effector T cells in mixed bone marrow chimeric mice during a parainfluenza virus infection. CXCR3-deficient effector CD4......(+) T cells were 5- to 10-fold less efficient at migrating to the lung compared with wild-type cells, whereas CCR5-deficient effector T cells were not impaired in their migration to the lung. In contrast to its role in trafficking, CXCR3 had no impact on effector CD4(+) T cell proliferation, phenotype...

  2. Ectopic expression of B-lymphoid kinase in cutaneous T-cell lymphoma

    DEFF Research Database (Denmark)

    Krejsgaard, Thorbjørn; Vetter-Kauczok, Claudia S; Woetmann, Anders;

    2009-01-01

    B-lymphoid kinase (Blk) is exclusively expressed in B cells and thymocytes. Interestingly, transgenic expression of a constitutively active form of Blk in the T-cell lineage of mice results in the development of T-lymphoid lymphomas. Here, we demonstrate nuclear factor-kappa B (NF......-kappaB)-mediated ectopic expression of Blk in malignant T-cell lines established from patients with cutaneous T-cell lymphoma (CTCL). Importantly, Blk is also expressed in situ in lesional tissue specimens from 26 of 31 patients with CTCL. Already in early disease the majority of epidermotropic T cells express Blk...... phosphorylated in malignant CTCL cell lines and spontaneously active in kinase assays. Furthermore, targeting Blk activity and expression by Src kinase inhibitors and small interfering RNA (siRNA) inhibit the proliferation of the malignant T cells. In conclusion, this is the first report of Blk expression...

  3. Remembering one's ID/E-ntity: E/ID protein regulation of T cell memory.

    Science.gov (United States)

    Omilusik, Kyla D; Shaw, Laura A; Goldrath, Ananda W

    2013-10-01

    Upon infection, CD8(+) T cells proliferate and differentiate into armed effector cells capable of eliminating the assaulting pathogen. Although the majority of the antigen-specific T cells will die as the immune response wanes, a few will survive indefinitely to establish the memory population and provide long-lived protection against reinfection. E protein transcription factors and their inhibitors, ID proteins, operate to balance expression of genes that control CD8(+) T cell differentiation through this process. Here, we discuss the role of ID2 and ID3 in promoting the generation and survival of effector and memory populations, particularly highlighting their reciprocal roles in shaping the CD8(+) T cell response unique to the inflammatory milieu. We further examine this coordinated control of gene expression in the context of additional transcription factors within the transcriptional network that programs CD8(+) effector and memory T cell differentiation.

  4. Bam32: a novel mediator of Erk activation in T cells.

    Science.gov (United States)

    Sommers, Connie L; Gurson, Jordan M; Surana, Rishi; Barda-Saad, Mira; Lee, Jan; Kishor, Aparna; Li, Wenmei; Gasser, Adam J; Barr, Valarie A; Miyaji, Michihiko; Love, Paul E; Samelson, Lawrence E

    2008-07-01

    Bam32 (B lymphocyte adapter molecule of 32 kDa) is an adapter protein expressed in some hematopoietic cells including B and T lymphocytes. It was previously shown that Bam32-deficient mice have defects in various aspects of B cell activation including B cell receptor (BCR)-induced Erk activation, BCR-induced proliferation and T-independent antibody responses. In this study, we have examined the role of Bam32 in T cell activation using Bam32-deficient mice. By comparing CD4(+) T cells from lymph nodes of wild-type and Bam32-deficient mice, we found that Bam32 was required for optimal TCR-induced Erk activation, cytokine production, proliferation and actin-mediated spreading of CD4(+) T cells. These results indicate a novel pathway to Erk activation in T cells involving the adapter protein Bam32.

  5. The Role of Matrine and Mitogen-Ativated Protein Kinase/Extracellular Signal-Regulated Kinase Signal Transduction in the Inhibition of the Proliferation and Migration of Human Umbilical Veins Endothelial Cells Induced by Lung Cancer cells

    Directory of Open Access Journals (Sweden)

    Ming BAI

    2009-07-01

    Full Text Available Background and objective Matrine, one of the major alkaloid components of the traditional Chinese medicine Sophora roots, has a wide range of pharmacological effects including anti-inflammatory activities, growth inhibition and induction of cell differentiation and apoptosis. Motigen-activated protein kinase (MAPK/extracellular signal-regulated kinase (ERK has found to be a crucial signaling pathway in endothelial cells. The aim of this study is to investigate the role of Matrine and MAPK/ERK signal transduction in the inhibition of the proliferation and migration of human umbilical veins endothelial cells (HUVECs induced by lung cancer cells. Methods HUVECs were cultured with A549CM. Mat or PD98059 (i.e PD, specific inhibitor of MAPK/ERK, was added into the A549CM. The proliferation of the HUVECs was measured by cell counting. The migration of the HUVECs was observed by wound healing assay. The expression levels of ERK and p-ERK protein were detected by Western Blot analysis. Results On 24 hours after intervention, the A549CM significantly stimulated the proliferation, migration and expression of p-ERK of HUVECs. Compared with the A549CM group, Mat significantly inhibited the proliferation, migration and p-ERK expression of HUVECs induced by A549CM. While PD only decreased the proliferation and p-ERK expression of HUVECs induced by A549CM. PD had no effect in the migration of HUVECs. Conclusion The results demonstrated that Mat and PD98059 can effectively decrease proliferation and expression of p-ERK of HUVECs induced by A549CM. Furthermore Mat can also inhibit migration of HUVECs induced by A549CM that did not changed by PD98059. These data implied that suppressing MAPK/ERK signal transduction may play the crucial role in resisting lung cacinoma angiogenesis with Mat.

  6. Characterization of the 17 strains of regulatory T cell-inducing human-derived Clostridia

    OpenAIRE

    Narushima, Seiko; Sugiura, Yuki; Oshima, Kenshiro; Atarashi, Koji; Hattori, Masahira; Suematsu, Makoto; Honda, Kenya

    2014-01-01

    The gut microbiota plays important roles in the development of the host immune system. We have previously shown that a combination of 46 strains of commensal Clostridia isolated from conventionally reared mice can induce the accumulation of CD4+Foxp3+ regulatory T (Treg) cells in the mouse colonic lamina propria. Subsequently, we succeeded in isolating and selecting 17 strains of Clostridia from a healthy human fecal sample that can significantly increase the number and function of colonic Tr...

  7. Immunoglobulin leakiness in scid mice with CD4(+) T-cell-induced chronic colitis

    DEFF Research Database (Denmark)

    Brimnes, J; Reimann, J; Claesson, Mogens Helweg

    2000-01-01

    development. In the present work we have investigated the relationship between disease progression and patterns or levels of Ig isotypes in the feces of scid mice suffering from an ongoing colitis. The data clearly showed that the severity or progression of the disease did not influence the levels of IgA, Ig......G1, IgG2a, IgG2b, and IgG3, whereas the level of fecal IgM increased during the course of colitis. The presence of the serum protein alpha-1-antitrypsin in fecal extracts from diseased mice suggests that some of the fecal Ig has leaked through the inflamed epithelial membrane into the gut lumen....... Finally, Ig-containing cells were observed in mesenteric lymph nodes and in the spleen, suggesting that the fecal Ig is produced both systemically and locally in the gut wall. In conclusion, the present results demonstrate that the level of IgM increases as colitis progresses. Also, the five remaining...

  8. Defects in CTLA-4 are associated with abnormal regulatory T cell function in rheumatoid arthritis

    OpenAIRE

    Flores-Borja, Fabian; Jury, Elizabeth C.; Mauri, Claudia; Ehrenstein, Michael R.

    2008-01-01

    The ultimate goal for the treatment of autoimmunity is to restore immunological tolerance. Regulatory T cells (Treg) play a central role in immune tolerance, and Treg functional abnormalities have been identified in different autoimmune diseases, including rheumatoid arthritis (RA). We have previously shown that natural Treg from RA patients are competent at suppressing responder T cell proliferation but not cytokine production. Here, we explore the hypothesis that this Treg defect in RA is l...

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

    Directory of Open Access Journals (Sweden)

    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.

  10. A Central Role for Induced Regulatory T Cells in Tolerance Induction in Experimental Colitis1

    OpenAIRE

    Haribhai, Dipica; Lin, Wen; Edwards, Brandon; Ziegelbauer, Jennifer; Salzman, Nita H.; Carlson, Marc R.; Li, Shun-Hwa; Simpson, Pippa M.; Chatila, Talal A; Williams, Calvin B.

    2009-01-01

    In addition to thymus-derived or natural T regulatory (nTreg) cells, a second subset of induced T regulatory (iTreg) cells arises de novo from conventional CD4+ T cells in the periphery. The function of iTreg cells in tolerance was examined in a CD45RBhighCD4+ T cell transfer model of colitis. In situ-generated iTreg cells were similar to nTreg cells in their capacity to suppress T cell proliferation in vitro and their absence in vivo accelerated bowel disease. Treatment with nTreg cells reso...

  11. SAG/Rbx2-Dependent Neddylation Regulates T-Cell Responses.

    Science.gov (United States)

    Mathewson, Nathan D; Fujiwara, Hideaki; Wu, Shin-Rong; Toubai, Tomomi; Oravecz-Wilson, Katherine; Sun, Yaping; Rossi, Corinne; Zajac, Cynthia; Sun, Yi; Reddy, Pavan

    2016-10-01

    Neddylation is a crucial post-translational modification that depends on the E3 cullin ring ligase (CRL). The E2-adapter component of the CRL, sensitive to apoptosis gene (SAG), is critical for the function of CRL-mediated ubiquitination; thus, the deletion of SAG regulates neddylation. We examined the role of SAG-dependent neddylation in T-cell-mediated immunity using multiple approaches: a novel T-cell-specific, SAG genetic knockout (KO) and chemical inhibition with small-molecule MLN4924. The KO animals were viable and showed phenotypically normal mature T-cell development. However, in vitro stimulation of KO T cells revealed significantly decreased activation, proliferation, and T-effector cytokine release, compared with WT. Using in vivo clinically relevant models of allogeneic bone marrow transplantation also demonstrated reduced proliferation and effector cytokine secretion associated with markedly reduced graft-versus-host disease. Similar in vitro and in vivo results were observed with the small-molecule inhibitor of neddylation, MLN4924. Mechanistic studies demonstrated that SAG-mediated effects in T cells were concomitant with an increase in suppressor of cytokine signaling, but not NF-κB translocation. Our studies suggest that SAG is a novel molecular target that regulates T-cell responses and that inhibiting neddylation with the clinically available small-molecule MLN4924 may represent a novel strategy to mitigate T-cell-mediated immunopathologies, such as graft-versus-host disease. PMID:27543965

  12. The effects of proliferation and injury in human peritoneal mesothelial cells induced by uric acid%尿酸对腹膜间皮细胞(HPMC)增殖、损伤的影响

    Institute of Scientific and Technical Information of China (English)

    詹林达; 徐伟杰; 黄锋先

    2009-01-01

    with various concentrations (200 ~ 1000 umol/L) uric acid increased the level of LDH at dose -dependent and time -dependent manner in HPMC. Conclusions The results indicate that uric acid may inhibit proliferation of HPMC and led to HPMC damage in vitro.%.

  13. T cell senescence and cardiovascular diseases.

    Science.gov (United States)

    Yu, Hee Tae; Park, Sungha; Shin, Eui-Cheol; Lee, Won-Woo

    2016-08-01

    Age-related changes in the immune system, commonly termed "immunosenescence," contribute to deterioration of the immune response and fundamentally impact the health and survival of elderly individuals. Immunosenescence affects both the innate and adaptive immune systems; however, the most notable changes are in T cell immunity and include thymic involution, the collapse of T cell receptor (TCR) diversity, an imbalance in T cell populations, and the clonal expansion of senescent T cells. Senescent T cells have the ability to produce large quantities of proinflammatory cytokines and cytotoxic mediators; thus, they have been implicated in the pathogenesis of many chronic inflammatory diseases. Recently, an increasing body of evidence has suggested that senescent T cells also have pathogenic potential in cardiovascular diseases, such as hypertension, atherosclerosis, and myocardial infarction, underscoring the detrimental roles of these cells in various chronic inflammatory responses. Given that cardiovascular disease is the number one cause of death worldwide, there is great interest in understanding the contribution of age-related immunological changes to its pathogenesis. In this review, we discuss general features of age-related alterations in T cell immunity and the possible roles of senescent T cells in the pathogenesis of cardiovascular disease. PMID:26188489

  14. T cell immune responses in psoriasis.

    Directory of Open Access Journals (Sweden)

    Zohre Jadali

    2014-08-01

    Full Text Available A central role for T cells and their cytokines in the pathogenesis of psoriasis has been proposed; however, there are controversies over the details of this issue. The goal of this study is to summarise currently available data on the importance of T cells in psoriasis pathogenesis. A systematic review of the English medical literature was conducted by searching PubMed, Embase, ISI Web of Knowledge, and Iranian databases including Iranmedex, and SID for studies on associations between the involvement of T cell subsets and psoriasis. The results of the present study indicate that alterations in the number and function of different subsets of T-cells are associated with psoriasis. It appears that studies on T cell subsets contributed to understanding the immunopathogenesis of psoriasis. In addition, it may have provided novel therapeutic opportunities in ameliorating immunopathologies.

  15. Targeting regulatory T cells in cancer.

    LENUS (Irish Health Repository)

    Byrne, William L

    2012-01-31

    Infiltration of tumors by regulatory T cells confers growth and metastatic advantages by inhibiting antitumor immunity and by production of receptor activator of NF-kappaB (RANK) ligand, which may directly stimulate metastatic propagation of RANK-expressing cancer cells. Modulation of regulatory T cells can enhance the efficacy of cancer immunotherapy. Strategies include depletion, interference with function, inhibition of tumoral migration, and exploitation of T-cell plasticity. Problems with these strategies include a lack of specificity, resulting in depletion of antitumor effector T cells or global interruption of regulatory T cells, which may predispose to autoimmune diseases. Emerging technologies, such as RNA interference and tetramer-based targeting, may have the potential to improve selectivity and efficacy.

  16. IL32 is progressively expressed in mycosis fungoides independent of helper T-cell 2 and helper T-cell 9 polarization.

    Science.gov (United States)

    Ohmatsu, Hanako; Humme, Daniel; Gulati, Nicholas; Gonzalez, Juana; Möbs, Markus; Suárez-Fariñas, Mayte; Cardinale, Irma; Mitsui, Hiroshi; Guttman-Yassky, Emma; Sterry, Wolfram; Krueger, James G

    2014-09-01

    Mycosis fungoides, the most common type of cutaneous T-cell lymphoma (CTCL), is characterized by a helper T-cell 2 (Th2) skewing with a mature CD4(+) memory T-cell phenotype. Using skin samples from patients with mycosis fungoides (n = 21), healthy volunteers (n = 17), and individuals with atopic dermatitis (n = 17) and psoriasis (n = 9), we found IL32 mRNA expression significantly higher in mycosis fungoides samples than in samples from benign inflammatory skin diseases, and its expression increases with disease progression. By IHC and immunofluorescence, we confirmed IL32 protein expression in many CD3(+)CD4(+) T cells and some epidermotropic T cells in mycosis fungoides lesions. MyLa cells (a mycosis fungoides cell line) express IL32, which, in turn, could promote cellular proliferation and viability in a dose-dependent fashion. IL32-treated MyLa and CTCL HH cells upregulated cell proliferation and survival genes. Of the major "polarizing" T-cell cytokines, only IFNγ mRNA increases with mycosis fungoides progression and positively correlates with IL32 mRNA expression. Th2 cytokines do not positively correlate with IL32 mRNA expression or mycosis fungoides progression. Furthermore, by flow cytometry, IL32 production by circulating activated T cells in healthy individuals was found in both IFNγ(+) and IFNγ(-) cells but not in IL4(+) or IL13(+) cells. In conclusion, we have identified IL32(+) cells as the likely tumor cells in mycosis fungoides, and demonstrated that IL32 mRNA expression increases with mycosis fungoides progression and is significantly higher than mRNA expression in other skin diseases, and that some IL32(+) T cells are independent from the defined Th subsets. Thus, IL32 may play a unique role in mycosis fungoides progression as an autocrine cytokine.

  17. Naïve T-Cell Dynamics in Human Immunodeficiency Virus Type 1 Infection: Effects of Highly Active Antiretroviral Therapy Provide Insights into the Mechanisms of Naïve T-Cell Depletion

    Science.gov (United States)

    Di Mascio, Michele; Sereti, Irini; Matthews, Lynn T.; Natarajan, Ven; Adelsberger, Joseph; Lempicki, Richard; Yoder, Christian; Jones, Elizabeth; Chow, Catherine; Metcalf, Julia A.; Sidorov, Igor A.; Dimitrov, Dimiter S.; Polis, Michael A.; Kovacs, Joseph A.

    2006-01-01

    Both naïve CD4+ and naïve CD8+ T cells are depleted in individuals with human immunodeficiency virus type 1 (HIV-1) infection by unknown mechanisms. Analysis of their dynamics prior to and after highly active antiretroviral therapy (HAART) could reveal possible mechanisms of depletion. Twenty patients were evaluated with immunophenotyping, intracellular Ki67 staining, T-cell receptor excision circle (TREC) quantitation in sorted CD4 and CD8 cells, and thymic computed tomography scans prior to and ∼6 and ∼18 months after initiation of HAART. Naïve T-cell proliferation decreased significantly during the first 6 months of therapy (P < 0.01) followed by a slower decline. Thymic indices did not change significantly over time. At baseline, naïve CD4+ T-cell numbers were lower than naive CD8+ T-cell numbers; after HAART, a greater increase in naïve CD4+ T cells than naïve CD8+ T cells was observed. A greater relative change (n-fold) in the number of TREC+ T cells/μl than in naïve T-cell counts was observed at 6 months for both CD4+ (median relative change [n-fold] of 2.2 and 1.7, respectively; P < 0.01) and CD8+ T cell pools (1.4 and 1.2; P < 0.01). A more pronounced decrease in the proliferation than the disappearance rate of naïve T cells after HAART was observed in a second group of six HIV-1-infected patients studied by in vivo pulse labeling with bromodeoxyuridine. These observations are consistent with a mathematical model where the HIV-1-induced increase in proliferation of naïve T cells is mostly explained by a faster recruitment into memory cells. PMID:16501076

  18. Designing T-cells with desired T-cell receptor make-up for immunotherapy

    NARCIS (Netherlands)

    Loenen, Margaretha Magdalena van

    2011-01-01

    TCR gene transfer is a strategy that enables the rapid engineering of anti-leukemic T-cells with defined specificity, resulting in a so called ‘off the shelf ‘ therapy. An elegant strategy to promote persistence of TCR modified T-cells may be TCR gene transfer into CMV- and EBV-specific T-cells, whi

  19. Generation of antigen-specific T cell immunity through T cell receptor gene transfer

    NARCIS (Netherlands)

    Coccoris, Miriam

    2009-01-01

    Cancer cells often escape the attack of immune cells because they originate from self-tissue. Through T cell receptor gene transfer it is possible to equip peripheral T cells with a desired specificity, and this strategy may be useful to generate tumor-specific T cells for the treatment of cancer in

  20. T cells in vascular inflammatory diseases

    Directory of Open Access Journals (Sweden)

    Lucas L Lintermans

    2014-10-01

    Full Text Available Inflammation of the human vasculature is a manifestation of many different diseases ranging from systemic autoimmune diseases to chronic inflammatory diseases, in which multiple types of immune cells are involved. For both autoimmune diseases and chronic inflammatory diseases several observations support a key role for T lymphocytes in these disease pathologies, but the underlying mechanisms are poorly understood. Previous studies in several autoimmune diseases have demonstrated a significant role for a specific subset of CD4+ T cells termed effector memory T cells. This expanded population of effector memory T cells may contribute to tissue injury and disease progression. These cells exert multiple pro-inflammatory functions through the release of effector cytokines. Many of these cytokines have been detected in the inflammatory lesions and participate in the vasculitic reaction, contributing to recruitment of macrophages, neutrophils, dendritic cells, NK cells, B cells and T cells. In addition, functional impairment of regulatory T cells paralyzes anti-inflammatory effects in vasculitic disorders. Interestingly, activation of effector memory T cells in uniquely dependent on the voltage-gated Kv1.3 potassium channel providing an anchor for specific drug targeting. In this review, we focus on the CD4+ T cells in the context of vascular inflammation and describe the evidence supporting the role of different T cell subsets in vascular inflammation. Selective targeting of pathogenic effector memory T cells might enable a more tailored therapeutic approach that avoids unwanted adverse side effects of generalized immunosuppression by modulating the effector functions of T cell responses to inhibit the development of vascular inflammation.

  1. The receptor for advanced glycation end products (RAGE) affects T cell differentiation in OVA induced asthma.

    Science.gov (United States)

    Akirav, Eitan M; Henegariu, Octavian; Preston-Hurlburt, Paula; Schmidt, Ann Marie; Clynes, Raphael; Herold, Kevan C

    2014-01-01

    The receptor for glycation end products (RAGE) has been previously implicated in shaping the adaptive immune response. RAGE is expressed in T cells after activation and constitutively in T cells from patients with diabetes. The effects of RAGE on adaptive immune responses are not clear: Previous reports show that RAGE blockade affects Th1 responses. To clarify the role of RAGE in adaptive immune responses and the mechanisms of its effects, we examined whether RAGE plays a role in T cell activation in a Th2 response involving ovalbumin (OVA)-induced asthma in mice. WT and RAGE deficient wild-type and OT-II mice, expressing a T cell receptor specific for OVA, were immunized intranasally with OVA. Lung cellular infiltration and T cell responses were analyzed by immunostaining, FACS, and multiplex bead analyses for cytokines. RAGE deficient mice showed reduced cellular infiltration in the bronchial alveolar lavage fluid and impaired T cell activation in the mediastinal lymph nodes when compared with WT mice. In addition, RAGE deficiency resulted in reduced OT-II T cell infiltration of the lung and impaired IFNγ and IL-5 production when compared with WT mice and reduced infiltration when transferred into WT hosts. When cultured under conditions favoring the differentiation of T cells subsets, RAGE deficient T cells showed reduced production of IFNγ but increased production of IL-17. Our data show a stimulatory role for RAGE in T activation in OVA-induced asthma. This role is largely mediated by the effects of RAGE on T cell proliferation and differentiation. These findings suggest that RAGE may play a regulatory role in T cell responses following immune activation.

  2. Mesenchymal stem cells differentially modulate effector CD8+ T cell subsets and exacerbate experimental autoimmune encephalomyelitis.

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    Glenn, Justin D; Smith, Matthew D; Calabresi, Peter A; Whartenby, Katharine A

    2014-10-01

    Mesenchymal stem cells (MSC) have emerged as a promising candidate for inflammatory suppression and disease amelioration, especially of neuro-inflammatory diseases such as multiple sclerosis (MS). Auto-reactive CD4+ and CD8+ T cells acquire pathogenic IFNγ-producing- (Type I) and IL-17A-producing- (Type 17) effector phenotypes in MS and its animal model experimental autoimmune encephalomyelitis (EAE). Although MSC have been extensively demonstrated to suppress pathogenic effector CD4+ T cells and CD4+ T cell-mediated EAE, surprisingly few studies have addressed their modulation of effector CD8+ T cells represented in MS or their impact on CD8+ T cell-mediated EAE. We find that MSC differentially modulate CD8+ T cell development depending on effector T cell subtype. MSC drive activated low-IFNγ producers toward an enhanced high-IFNγ Tc1-like phenotype but strongly inhibit the production of IL-17A and Tc17 polarization in vitro. These observations are underscored by differential MSC modulation of T cell activation, proliferation, and signature transcription factor up-regulation. In addition, effector CD8+ T cells co-cultured with MSC exhibited increased production of IL-2, a molecule known to enhance IFNγ, yet suppress IL-17A, production. Based on these in vitro effects on CD8+ T cells, we next evaluated their impact on the severity of EAE. To better evaluate CD8+ T cells, we immunized mice with MOG37-50 , which is a CD8-targeted epitope. Our results revealed a worsening of disease, consistent with their in vitro stimulation of Tc1 cells. These findings highlight the emerging duality of MSC in immune modulation and provide implications for their future use in immune-related diseases. PMID:24911892

  3. Circulating rotavirus-specific T cells have a poor functional profile

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    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.

  4. When aging reaches CD4+ T-cells: phenotypic and functional changes

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    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.

  5. Exploring T Cell Reactivity to Gliadin in Young Children with Newly Diagnosed Celiac Disease

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    Edwin Liu

    2014-01-01

    Full Text Available Class II major histocompatibility molecules confer disease risk in Celiac disease (CD by presenting gliadin peptides to CD4 T cells in the small intestine. Deamidation of gliadin peptides by tissue transglutaminase creates immunogenic peptides presented by HLA-DQ2 and DQ8 molecules to activate proinflammatory CD4 T cells. Detecting gliadin specific T cell responses from the peripheral blood has been challenging due to low circulating frequencies and heterogeneity in response to gliadin epitopes. We investigated the peripheral T cell responses to alpha and gamma gliadin epitopes in young children with newly diagnosed and untreated CD. Using peptide/MHC recombinant protein constructs, we are able to robustly stimulate CD4 T cell clones previously derived from intestinal biopsies of CD patients. These recombinant proteins and a panel of α- and γ-gliadin peptides were used to assess T cell responses from the peripheral blood. Proliferation assays using peripheral blood mononuclear cells revealed more CD4 T cell responses to α-gliadin than γ-gliadin peptides with a single deamidated α-gliadin peptide able to identify 60% of CD children. We conclude that it is possible to detect T cell responses without a gluten challenge or in vitro stimulus other than antigen, when measuring proliferative responses.

  6. Novel function of perforin in negatively regulating CD4+T cell activation by affecting calcium signaling

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    Enguang Bi; Kairui Mao; Jia Zou; Yuhan Zheng; Bing Sun; Chunjian Huang; Yu Hu; Xiaodong Wu; Weiwen Deng; Guomei Lin; Zhiduo Liu; Lin Tian; Shuhui Sun

    2009-01-01

    Perforin is a pore-forming protein engaged mainly in mediating target T cell death and is employed by cytotoxic Tlymphocytes (CTLs) and natural killer cells. However, whether it also plays a role in conventional CD4+ T cell func-tion remains unclear. Here we report that in perforin-deficient (PKO) mice, CD4+ T cells are hyperproliferative in response to T cell receptor (TCR) stimulation. This feature of hyperproliferation is accompanied by the enhancement both in cell division and in IL-2 secretion. It seems that the perforin deficiency does not influence T cell development in thymus spleen and lymph node. In vivo, perforin deficiency results in increased antigen-specific T cell prolifera-tion and antibody production. Furthermore, PKO mice are more susceptible to experimental autoimmune uveitis. To address the molecular mechanism, we found that after TCR stimulation, CD44 T cells from PKO mice display an increased intracellular calcium flux and subsequently enhance activation of transcription factor NFATI. Our results indicate that perforin plays a negative role in regulating CD4+ T cell activation and immune response by affecting TCR-dependent Ca2+ signaling.

  7. CD4(+)CD25 (+)CD127 (low/-) T cells: a more specific Treg population in human peripheral blood.

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    Yu, Ning; Li, Xiaomei; Song, Weiya; Li, Dongmei; Yu, Daliang; Zeng, Xiaofeng; Li, Mengtao; Leng, Xiaomei; Li, Xiangpei

    2012-12-01

    The quantitative identification and enrichment of viable regulatory T cells (Treg) requires reliable surface markers that are selectively expressed on Treg. Foxp3 is the accepted marker of nTreg, but it cannot be used to isolate cells for functional studies. In this study, we compared four staining profiles of Treg, including CD4(+)CD25(high) T cells, CD4(+)CD39(+) T cells, CD4(+)CD73(+) T cells, and CD4(+)CD25(+)CD127(low/-) T cells. We found that CD4(+)CD25(+)CD127(low/-) T cells expressed the highest level of Foxp3 and had the strongest correlation with CD4(+)CD25(+)Foxp3(+) T cells, the accepted identifying characteristics for "real" nTreg cells. Moreover, functional data showed that CD4(+)CD25(+)CD127(low/-) T cells could effectively suppress the proliferation of CD4(+)CD25(-) T cells, suggesting that compared with the other three populations, CD4(+)CD25(+)CD127(low/-) T cells best fit the definition of naturally occurring regulatory T cells in human peripheral blood. Finally, we showed that CD4(+)CD25(+)CD127(low/-) can be used to quantitate Treg cells in individuals with systemic lupus erythematosus supporting the use of CD4(+)CD25(+)CD127(low/-) to identify human Treg cells. PMID:22752562

  8. B cells help alloreactive T cells differentiate into memory T cells1

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    Ng, Yue-Harn; Oberbarnscheidt, Martin H.; Chandramoorthy, Harish Chinna Konda; Hoffman, Rosemary; Chalasani, Geetha

    2010-01-01

    B cells are recognized as effector cells in allograft rejection that are dependent upon T cell help to produce alloantibodies causing graft injury. It is not known if B cells can also help T cells differentiate into memory cells in the alloimmune response. We found that in B cell-deficient hosts, differentiation of alloreactive T cells into effectors was intact whereas their development into memory T cells was impaired. To test if B cell help for T cells was required for their continued diffe...

  9. Determinants of public T cell responses

    Institute of Scientific and Technical Information of China (English)

    Hanjie Li; Congting Ye; Guoli Ji; Jiahuai Han

    2012-01-01

    Historically,sharing T cell receptors (TCRs) between individuals has been speculated to be impossible,considering the dramatic discrepancy between the potential enormity of the TCR repertoire and the limited number of T cells generated in each individual.However,public T cell response,in which multiple individuals share identical TCRs in responding to a same antigenic epitope,has been extensively observed in a variety of immune responses across many species.Public T cell responses enable individuals within a population to generate similar antigen-specific TCRs against certain ubiquitous pathogens,leading to favorable biological outcomes.However,the relatively concentrated feature of TCR repertoire may limit T cell response in a population to some other pathogens.It could be a great benefit for human health if public T cell responses can be manipulated.Therefore,the mechanistic insight of public TCR generation is important to know.Recently,high-throughput DNA sequencing has revolutionized the study of immune receptor repertoires,which allows a much better understanding of the factors that determine the overlap of TCR repertoire among individuals.Here,we summarize the current knowledge on public T-cell response and discuss future challenges in this field.

  10. Tumor Evasion from T Cell Surveillance

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    Katrin Töpfer

    2011-01-01

    Full Text Available An intact immune system is essential to prevent the development and progression of neoplastic cells in a process termed immune surveillance. During this process the innate and the adaptive immune systems closely cooperate and especially T cells play an important role to detect and eliminate tumor cells. Due to the mechanism of central tolerance the frequency of T cells displaying appropriate arranged tumor-peptide-specific-T-cell receptors is very low and their activation by professional antigen-presenting cells, such as dendritic cells, is frequently hampered by insufficient costimulation resulting in peripheral tolerance. In addition, inhibitory immune circuits can impair an efficient antitumoral response of reactive T cells. It also has been demonstrated that large tumor burden can promote a state of immunosuppression that in turn can facilitate neoplastic progression. Moreover, tumor cells, which mostly are genetically instable, can gain rescue mechanisms which further impair immune surveillance by T cells. Herein, we summarize the data on how tumor cells evade T-cell immune surveillance with the focus on solid tumors and describe approaches to improve anticancer capacity of T cells.

  11. Photodynamic effects on T-cells and skin lesions of a patient with mycosis fungoides using porphyrin photosensitizers

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    Koenig, Karsten; Boehncke, Wolf-Henning; Rueck, Angelika C.; Kaufmann, Roland; Steiner, Rudolf W.; Sterry, Wolfram

    1994-02-01

    PUVA is a well established phototreatment modality for various dermatoses, like T cell lymphomas, using long-wavelength UV radiation. In contrast, PDT bases on the combination of photosensitizers, especially porphyrins, and radiation mainly in the red spectral region. We analyzed the photochemical effects of both treatments on cell lines MyLa and HuT78, established from patients with cutaneous T cell lymphomas. Our observations document the capability of PDT to inhibit proliferation of transformed T cells similar to PUVA thus pointing out its potential in the treatment of cutaneous T cell lymphomas.

  12. Chloroquine treatment enhances regulatory T cells and reduces the severity of experimental autoimmune encephalomyelitis.

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    Rodolfo Thomé

    Full Text Available BACKGROUND: The modulation of inflammatory processes is a necessary step, mostly orchestrated by regulatory T (Treg cells and suppressive Dendritic Cells (DCs, to prevent the development of deleterious responses and autoimmune diseases. Therapies that focused on adoptive transfer of Treg cells or their expansion in vivo achieved great success in controlling inflammation in several experimental models. Chloroquine (CQ, an anti-malarial drug, was shown to reduce inflammation, although the mechanisms are still obscure. In this context, we aimed to access whether chloroquine treatment alters the frequency of Treg cells and DCs in normal mice. In addition, the effects of the prophylactic and therapeutic treatment with CQ on Experimental Autoimmune Encephalomyelitis (EAE, an experimental model for human Multiple Sclerosis, was investigated as well. METHODOLOGY/PRINCIPAL FINDINGS: EAE was induced in C57BL/6 mice by immunization with myelin oligodendrocyte glycoprotein (MOG35-55 peptide. C57BL/6 mice were intraperitoneally treated with chloroquine. Results show that the CQ treatment provoked an increase in Treg cells frequency as well as a decrease in DCs. We next evaluated whether prophylactic CQ administration is capable of reducing the clinical and histopathological signs of EAE. Our results demonstrated that CQ-treated mice developed mild EAE compared to controls that was associated with lower infiltration of inflammatory cells in the central nervous system CNS and increased frequency of Treg cells. Also, proliferation of MOG35-55-reactive T cells was significantly inhibited by chloroquine treatment. Similar results were observed when chloroquine was administrated after disease onset. CONCLUSION: We show for the first time that CQ treatment promotes the expansion of Treg cells, corroborating previous reports indicating that chloroquine has immunomodulatory properties. Our results also show that CQ treatment suppress the inflammation in the CNS of

  13. Clinical Strategies to Enhance T cell Reconstitution

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    Goldberg, Gabrielle L; Zakrzewski, Johannes L; Perales, Miguel A; van den Brink, Marcel R.M.

    2009-01-01

    Strategies to enhance T cell recovery are of increasing clinical importance to overcome long lasting T cell deficiencies, which occur in association with infections, autoimmunity and chemo/radiotherapy as well as aging of the immune system. In this review we discuss those strategies that are close to or in the clinic. Interleukin-7, sex steroid modulation, keratinocyte growth factor, growth hormone and cellular therapies using ex vivo generated T cell precursors are currently being tested in recipients of a hematopoietic stem cell transplantation and patients with malignancies or HIV/AIDS. PMID:17964803

  14. Microenvironmental cues for T-cell acute lymphoblastic leukemia development.

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    Passaro, Diana; Quang, Christine Tran; Ghysdael, Jacques

    2016-05-01

    Intensive chemotherapy regimens have led to a substantial improvement in the cure rate of patients suffering from T-cell acute lymphoblastic leukemia (T-ALL). Despite this progress, about 15% and 50% of pediatric and adult cases, respectively, show resistance to treatment or relapse with dismal prognosis, calling for further therapeutic investigations. T-ALL is an heterogeneous disease, which presents intrinsic alterations leading to aberrant expression of transcription factors normally involved in hematopoietic stem/progenitor cell development and mutations in genes implicated in the regulation of cell cycle progression, apoptosis, and T-cell development. Gene expression profiling allowed the classification of T-ALL into defined molecular subgroups that mostly reflects the stage of their differentiation arrest. So far this knowledge has not translated into novel, targeted therapy. Recent evidence points to the importance of extrinsic signaling cues in controlling the ability of T-ALL to home, survive, and proliferate, thus offering the perspective of new therapeutic options. This review summarizes the present understanding of the interactions between hematopoietic cells and bone marrow/thymic niches during normal hematopoiesis, describes the main signaling pathways implicated in this dialog, and finally highlights how malignant T cells rely on specific niches to maintain their ability to sustain and propagate leukemia. PMID:27088913

  15. Dexamethasone inhibits IL-9 production by human T cells

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    Cormont Francoise

    2005-04-01

    Full Text Available Abstract Background Interleukin 9 (IL-9 is produced by activated CD4+ T cells. Its effects include stimulation of mucus production, enhanced mast cell proliferation, enhanced eosinophil function, and IgE production. These effects are consistent with a role in allergic diseases. Glucocorticoids have potent anti-inflammatory effects, including suppression of cytokine synthesis, and are widely used in the treatment of allergic conditions. Methods We examined the effect of the glucocorticoid dexamethasone (Dex on IL-9 mRNA expression and protein secretion with real-time RT-PCR and ELISA. Peripheral blood mononuclear cells (PBMC were prepared from human volunteers and activated with OKT3. CD4+ T cells were purified from PBMC and activated with OKT3 plus PMA. Results IL-9 mRNA abundance and protein secretion were both markedly reduced following treatment of activated PBMC with Dex. mRNA levels were reduced to 0.7% of control values and protein secretion was reduced to 2.8% of controls. In CD4+ T cells, Dex reduced protein secretion to a similar extent. The IC50 value of Dex on mRNA expression was 4 nM. Conclusion These results indicate that IL-9 production is very markedly inhibited by Dex. The findings raise the possibility that the beneficial effects of glucocorticoids in the treatment of allergic diseases are in part mediated by inhibition of IL-9 production.

  16. Enhancement of CD4(+) T cell response and survival via coexpressed OX40/OX40L in Graves' disease.

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    Wang, Qin; Shi, Bi-Min; Xie, Fang; Fu, Zhao-Yang; Chen, Yong-Jing; An, Jing-Nan; Ma, Yu; Liu, Cui-Ping; Zhang, Xue-Kun; Zhang, Xue-Guang

    2016-07-15

    OX40/OX40L pathway plays a very important role in the antigen priming T cells and effector T cells. In the present study, we aimed to examine the involvement of OX40/OX40L pathway in the activation of autoreactive T cells in patients with Grave's disease (GD). We found that OX40 and OX40L were constitutively coexpressed on peripheral CD4(+) T cells from GD patients using flow cytometry analysis. The levels of OX40 and OX40L coexpression on CD4(+) T cells were shown to be correlated with TRAbs. Cell proliferation assay showed that blocking OX40/OX40L signal inhibited T cell proliferation and survival, which suggested that OX40/OX40L could enhance CD4(+) T cell proliferation and maintain their long-term survival in GD by self-enhancing loop of T cell activation independent of APCs. Confocal microscopy and coimmunoprecipitation analysis further revealed that OX40 and OX40L formed a functional complex, which may facilitate signal transduction from OX40L to OX40 and contribute to the pathogenesis of GD. PMID:27107937

  17. Radiosensitivity of CD45RO{sup +} memory and CD45RO{sup {minus}} naive T cells in culture

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    Uzawa, Akiko; Suzuki, Gen; Nakata, Yukiko; Akashi, Makoto; Ohyama, Harumi; Akanuma, Atsuo [National Institute of Radiological Sciences, Chiba (Japan)

    1994-01-01

    Radiosensitivities of various human T-cell subsets were investigated by a proliferation assay and by a single-cell gel electrophoresis assay. Each T-cell subset was purified using a cell sorter and was induced to proliferate by ionomycin and interleukin 2. Unsorted T cells showed biphasic dose-survival curves, indicating the heterogeneity of T cells in terms of radiosensitivity. Purified CD4{sup +} helper and CD8{sup +} killer T cells showed similar biphasic dose-survival curves. Hence both T-cell subsets were composed of cells of different radiosensitivity. The T-cell subsets belonging to different activation stages such as CD45RO{sup +} memory and CD45RO{sup {minus}} naive T cells had different dose-survival curves. The former was more radiosensitive than the latter. The high radiosensitivity of CD45RO{sup +} cells was also demonstrated by single-cell gel electrophoresis after irradiation. This is the first demonstration that a particular cell surface marker on T cells is correlated with greater radiosensitivity. 27 refs., 7 figs., 1 tab.

  18. Molecular Pathology of Adult T-Cell Leukemia/Lymphoma.

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    Ohshima, Koichi

    2015-01-01

    Adult T-cell leukemia/lymphoma (ATLL) is a peripheral T-cell neoplasm of highly pleomorphic lymphoid cells. ATLL is usually widely disseminated, and it is caused by human T-cell leukemia virus type 1 (HTLV-1). It is a disease with a long latency, and affected individuals are usually exposed to the virus very early in life. The cumulative incidence of ATLL is estimated to be 2.5% among HTLV-1 carriers. ATLL cells express CD2, CD3, CD5, CD4, and CD25, as well as CCR4 and FoxP3 of the regulatory T-cell marker. HTLV-1 is causally linked to ATLL, but infection alone is not sufficient to result in neoplastic transformation. A significant finding in this connection is that the Tax viral protein leads to transcriptional activation of many genes, while the HTLV-1 basic leucine zipper factor is thought to be important for T-cell proliferation and oncogenesis. Half of ATLL cases retain the ability to express HTLV-1 Tax, which is a target of HTLV-1-specific cytotoxic T lymphocytes (CTL). An increase in HTLV-1-specific CTL responses is observed in some asymptomatic HTLV-1 carriers. Although HTLV-1-specific CTL are also present in the peripheral blood of ATLL patients, they do not expand sufficiently. We investigated the clinicopathological features and analyzed the staining of Tax-specific CTL and FoxP3. Tax-specific CTL correlated inversely with FoxP3, an increase in the ratio of CD163+ tumor-associated macrophages was associated with worse clinical prognosis, and ATLL cell lines proliferated significantly following direct co-culture with M2 macrophages. Several clinical variants of ATLL have been identified: acute, lymphomatous, chronic, and smoldering. Oligo-array comparative genomic hybridization revealed that genomic loss of 9p21.3 was a significant characteristic of acute-type, but not of chronic-type ATLL. Furthermore, we found that genomic alteration of CD58, which is implicated in immune escape, is more frequently observed in acute than in chronic ATLL. Interestingly

  19. Distribution, characterization, and induction of CD8+ regulatory T cells and IL-17-producing CD8+ T cells in nasopharyngeal carcinoma

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    Li Jiang

    2011-11-01

    Full Text Available Abstract Background CD8+ effector cells often have an antitumor function in patients with cancer. However, CD8+Foxp3+ regulatory T cells (Tcregs and interleukin (IL-17-producing CD8+ T cells (Tc17 cells also derive from the CD8+ T cell lineage. Their role in the antitumor response remains largely unknown. In the present study, we aimed to investigate the distribution, characterization, and generation of CD8+ Tcregs and Tc17 cells in NPC patients. Methods Peripheral blood and tumor biopsy tissues from 21 newly diagnosed patients with nasopharyngeal carcinoma (NPC were collected, along with peripheral blood from 21 healthy donors. The biological characteristics of Tcregs and Tc17 cells from blood and tumor tissues were examined by intracellular staining, tetramer staining and fluorescence-activated cell sorting (FACS analysis. The suppressive function of Tcregs was investigated using a proliferation assay that involved co-culture of sorted CD8+CD25+ T cells with naïve CD4+ T cells in vitro. Results We observed an increased prevalence of Tcregs and Tc17 cells among tumor-infiltrating lymphocytes (TILs and different distribution among peripheral blood mononuclear cells (PBMCs in NPC patients. Cytokine profiles showed that the Tcregs expressed a high level of IL-10 and low level of transforming growth factor β, whereas Tc17 cells expressed a high level of tumor necrosis factor α. Interestingly, both subsets expressed a high level of interferon γ in TILs, and the Tcregs suppressed naïve CD4+ T cell proliferation by a cell contact-dependent mechanism in vitro. Moreover, we demonstrated the existence of Epstein-Barr virus latent membrane protein (LMP 1 and LMP2 antigen-specific Tcregs in NPC. Conclusions Our data provide new insights into the composition and function of CD8+ T-cell subsets in NPC, which may have an important influence on NPC immunotherapy.

  20. Regulatory T-cell compartmentalization and trafficking

    OpenAIRE

    Wei, Shuang; Kryczek, Ilona; Zou, Weiping

    2006-01-01

    CD4+CD25+FOXP3+ regulatory T cells (CD4+ Treg cells) are thought to differentiate in the thymus and immigrate from the thymus to the periphery. Treg cells can regulate both acquired and innate immunity through multiple modes of suppression. The cross-talk between Treg cells and targeted cells, such as antigen-presenting cells (APCs) and T cells, is crucial for ensuring suppression by Treg cells in the appropriate microenvironment. Emerging evidence suggests that Treg compartmentalization and ...

  1. Regulatory T cells in cutaneous immune responses.

    OpenAIRE

    Honda, Tetsuya; MIYACHI, YOSHIKI; Kabashima, Kenji

    2011-01-01

    Regulatory T cells (Treg) are a subset of T cells with strong immunosuppressive activity. In the skin, it has recently been revealed that Treg play important roles not only in the maintenance of skin homeostasis but also in the regulation of the immune responses, such as contact hypersensitivity and atopic dermatitis. Furthermore, the skin plays important roles in the induction of Treg in the periphery. In this review, we will provide an overview of the mechanism of Treg-mediated immunosuppre...

  2. How do Regulatory T Cells Work?

    OpenAIRE

    Corthay, A

    2009-01-01

    CD4+ T cells are commonly divided into regulatory T (Treg) cells and conventional T helper (Th) cells. Th cells control adaptive immunity against pathogens and cancer by activating other effector immune cells. Treg cells are defined as CD4+ T cells in charge of suppressing potentially deleterious activities of Th cells. This review briefly summarizes the current knowledge in the Treg field and defines some key questions that remain to be answered. Suggested functions for Treg cells include: p...

  3. CELLULAR AND POPULATION PLASTICITY OF HELPER CD4 T CELL RESPONSES

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    Gesham eMagombedze

    2013-08-01

    Full Text Available Vertebrates are constantly exposed to pathogens, and the adaptive immunity has most likely evolved to control and clear such infectious agents. CD4 T cells are the major players in the adaptive immune response to pathogens. Following recognition of pathogen-derived antigens naïve CD4 T cells differentiate into effectors which then control pathogen replication either directly by killing pathogen-infected cells or by assisting with generation of cytotoxic T lymphocytes or pathogen-specific antibodies. Pathogen-specific effector CD4 T cells are highly heterogeneous in terms of cytokines they produce. Three major subtypes of effector CD4 T cells have been identified: T-helper 1 (Th1 cells producing IFN-g and TNF-α, Th2 cells producing IL-4 and IL-10, and Th17 cells producing IL-17. How this heterogeneity is maintained and what regulates changes in effector T cell composition during chronic infections remains poorly understood. In this review we discuss recent advances in our understanding of CD4 T cell differentiation in response to microbial infections. We propose that a change in the phenotype of pathogen-specific effector CD4 T cells during chronic infections, for example, from Th1 to Th2 response as observed in Mycobacteriumavium ssp. paratuberculosis (MAP infection of ruminants, can be achieved by conversion of T cells from one effector subset to another (cellular plasticity or due to differences in kinetics (differentiation, proliferation, death of different effector T cell subsets (population plasticity. We also shortly review mathematical models aimed at describing CD4 T cell differentiation and outline areas for future experimental and theoretical research.

  4. Reconstitution of CD4 T Cells in Bronchoalveolar Lavage Fluid after Initiation of Highly Active Antiretroviral Therapy▿

    Science.gov (United States)

    Knox, Kenneth S.; Vinton, Carol; Hage, Chadi A.; Kohli, Lisa M.; Twigg, Homer L.; Klatt, Nichole R.; Zwickl, Beth; Waltz, Jeffrey; Goldman, Mitchell; Douek, Daniel C.; Brenchley, Jason M.

    2010-01-01

    The massive depletion of gastrointestinal-tract CD4 T cells is a hallmark of the acute phase of HIV infection. In contrast, the depletion of the lower-respiratory-tract mucosal CD4 T cells as measured in bronchoalveolar lavage (BAL) fluid is more moderate and similar to the depletion of CD4 T cells observed in peripheral blood (PB). To understand better the dynamics of disease pathogenesis and the potential for the reconstitution of CD4 T cells in the lung and PB following the administration of effective antiretroviral therapy, we studied cell-associated viral loads, CD4 T-cell frequencies, and phenotypic and functional profiles of antigen-specific CD4 T cells from BAL fluid and blood before and after the initiation of highly active antiretroviral therapy (HAART). The major findings to emerge were the following: (i) BAL CD4 T cells are not massively depleted or preferentially infected by HIV compared to levels for PB; (ii) BAL CD4 T cells reconstitute after the initiation of HAART, and their infection frequencies decrease; (iii) BAL CD4 T-cell reconstitution appears to occur via the local proliferation of resident BAL CD4 T cells rather than redistribution; and (iv) BAL CD4 T cells are more polyfunctional than CD4 T cells in blood, and their functional profile is relatively unchanged after the initiation of HAART. Taken together, these data suggest mechanisms for mucosal CD4 T-cell depletion and interventions that might aid in the reconstitution of mucosal CD4 T cells. PMID:20610726

  5. T Cell Functional Disturbances in Patients with Pulmonary Tuberculosis.

    Science.gov (United States)

    Ostanin, Alexander A.; Khonina, Nataliya A.; Norkin, Maxim N.; Leplina, Olga Yu.; Nikonov, Sergey D.; Ogirenko, Anatoly P.; Chernykh, Helen R.

    2000-04-01

    The investigations of 38 patients with pulmonary tuberculosis (PT) revealed combined T cell and monocyte functional disturbances. Indeed, the percentages of CD4(+) and CD8(+) T lymphocytes, proliferative response and IL-2 production, as well as the percentages of HLA DR(+) monocytes and IL-1beta production were significantly decreased in PT patients as compared with normal individuals. Herewith the absolute T lymphocyte number did not undergo the pronounced changes. The decrease of T cell proliferative response was not mediated through immunosuppressive action of monocytes or T lymphocytes since removing of "adherent" cells from patient's peripheral blood mononuclear cells (PBMC) or pretreatment of PBMC with indomethacin and cyclophosphan failed to recover mitogenic reactivity in vitro. The patient's sera also did not significantly influence on PBMC proliferation. The decrease of IL-2 production and the stimulation of T cell proliferative response via TcR-CD3 complex, i.e. through the classic pathway of activation, indicated the anergy of T lymphocyte in tuberculosis patients. Furthermore, T lymphocytes were characterized by enhanced apoptosis. It should be noted, that patient's sera (especially in the patients with an initially high apoptosis) promoted significant anti-apoptotic activity. It is likely that this mechanism may be an explanation, why absolute T lymphopenia is absent during tuberculosis infection. Our findings suggest, that T lymphocyte dysfunctions in patients with PT are caused by impairments of T cell activation process, which lead to predominance of "negative" response (induction anergy, apoptosis) and to a lesser degree connected with direct suppressive mechanisms mediated by monocytes, T lymphocytes or serum factors.

  6. 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

    2016-09-01

    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.

  7. CD4+ T cell effects on CD8+ T cell location defined using bioluminescence.

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    Mitra Azadniv

    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.

  8. Distinct roles of Cdc42 in thymopoiesis and effector and memory T cell differentiation.

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    Fukun Guo

    Full Text Available Cdc42 of the Rho GTPase family has been implicated in cell actin organization, proliferation, survival, and migration but its physiological role is likely cell-type specific. By a T cell-specific deletion of Cdc42 in mouse, we have recently shown that Cdc42 maintains naïve T cell homeostasis through promoting cell survival and suppressing T cell activation. Here we have further investigated the involvement of Cdc42 in multiple stages of T cell differentiation. We found that in Cdc42(-/- thymus, positive selection of CD4(+CD8(+ double-positive thymocytes was defective, CD4(+ and CD8(+ single-positive thymocytes were impaired in migration and showed an increase in cell apoptosis triggered by anti-CD3/-CD28 antibodies, and thymocytes were hyporesponsive to anti-CD3/-CD28-induced cell proliferation and hyperresponsive to anti-CD3/-CD28-stimulated MAP kinase activation. At the periphery, Cdc42-deficient naive T cells displayed an impaired actin polymerization and TCR clustering during the formation of mature immunological synapse, and showed an enhanced differentiation to Th1 and CD8(+ effector and memory cells in vitro and in vivo. Finally, Cdc42(-/- mice exhibited exacerbated liver damage in an induced autoimmune disease model. Collectively, these data establish that Cdc42 is critically involved in thymopoiesis and plays a restrictive role in effector and memory T cell differentiation and autoimmunity.

  9. B7-H4 Treatment of T Cells Inhibits ERK, JNK, p38, and AKT Activation

    Science.gov (United States)

    Wang, Xiaojie; Hao, Jianqiang; Metzger, Daniel L.; Ao, Ziliang; Chen, Lieping; Ou, Dawei; Verchere, C. Bruce; Mui, Alice; Warnock, Garth L.

    2012-01-01

    B7-H4 is a newly identified B7 homolog that plays an important role in maintaining T-cell homeostasis by inhibiting T-cell proliferation and lymphokine-secretion. In this study, we investigated the signal transduction pathways inhibited by B7-H4 engagement in mouse T cells. We found that treatment of CD3+ T cells with a B7-H4.Ig fusion protein inhibits anti-CD3 elicited T-cell receptor (TCR)/CD28 signaling events, including phosphorylation of the MAP kinases, ERK, p38, and JNK. B7-H4.Ig treatment also inhibited the phosphorylation of AKT kinase and impaired its kinase activity as assessed by the phosphorylation of its endogenous substrate GSK-3. Expression of IL-2 is also reduced by B7-H4. In contrast, the phosphorylation state of the TCR proximal tyrosine kinases ZAP70 and lymphocyte-specific protein tyrosine kinase (LCK) are not affected by B7-H4 ligation. These results indicate that B7-H4 inhibits T-cell proliferation and IL-2 production through interfering with activation of ERK, JNK, and AKT, but not of ZAP70 or LCK. PMID:22238573

  10. B7-H4 Treatment of T Cells Inhibits ERK, JNK, p38, and AKT Activation.

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    Xiaojie Wang

    Full Text Available B7-H4 is a newly identified B7 homolog that plays an important role in maintaining T-cell homeostasis by inhibiting T-cell proliferation and lymphokine-secretion. In this study, we investigated the signal transduction pathways inhibited by B7-H4 engagement in mouse T cells. We found that treatment of CD3(+ T cells with a B7-H4.Ig fusion protein inhibits anti-CD3 elicited T-cell receptor (TCR/CD28 signaling events, including phosphorylation of the MAP kinases, ERK, p38, and JNK. B7-H4.Ig treatment also inhibited the phosphorylation of AKT kinase and impaired its kinase activity as assessed by the phosphorylation of its endogenous substrate GSK-3. Expression of IL-2 is also reduced by B7-H4. In contrast, the phosphorylation state of the TCR proximal tyrosine kinases ZAP70 and lymphocyte-specific protein tyrosine kinase (LCK are not affected by B7-H4 ligation. These results indicate that B7-H4 inhibits T-cell proliferation and IL-2 production through interfering with activation of ERK, JNK, and AKT, but not of ZAP70 or LCK.

  11. Highly-Immunogenic Virally-Vectored T-cell Vaccines Cannot Overcome Subversion of the T-cell Response by HCV during Chronic Infection.

    Science.gov (United States)

    Swadling, Leo; Halliday, John; Kelly, Christabel; Brown, Anthony; Capone, Stefania; Ansari, M Azim; Bonsall, David; Richardson, Rachel; Hartnell, Felicity; Collier, Jane; Ammendola, Virginia; Del Sorbo, Mariarosaria; Von Delft, Annette; Traboni, Cinzia; Hill, Adrian V S; Colloca, Stefano; Nicosia, Alfredo; Cortese, Riccardo; Klenerman, Paul; Folgori, Antonella; Barnes, Eleanor

    2016-01-01

    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 were

  12. 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

  13. Highly-Immunogenic Virally-Vectored T-cell Vaccines Cannot Overcome Subversion of the T-cell Response by HCV during Chronic Infection

    Science.gov (United States)

    Swadling, Leo; Halliday, John; Kelly, Christabel; Brown, Anthony; Capone, Stefania; Ansari, M. Azim; Bonsall, David; Richardson, Rachel; Hartnell, Felicity; Collier, Jane; Ammendola, Virginia; Del Sorbo, Mariarosaria; Von Delft, Annette; Traboni, Cinzia; Hill, Adrian V. S.; Colloca, Stefano; Nicosia, Alfredo; Cortese, Riccardo; Klenerman, Paul; Folgori, Antonella; Barnes, Eleanor

    2016-01-01

    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 were

  14. Malaria drives T cells to exhaustion

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    Michelle N Wykes

    2014-05-01

    Full Text Available Malaria is a significant global burden but after >30 years of effort there is no vaccine on the market. While the complex life cycle of the parasite presents several challenges, many years of research have also identified several mechanisms of immune evasion by Plasmodium spp.. Recent research on malaria, has investigated the Programmed cell death-1 (PD-1 pathway which mediates exhaustion of T cells, characterized by poor effector functions and recall responses and in some cases loss of the cells by apoptosis. Such studies have shown exhaustion of CD4+ T cells and an unappreciated role for CD8+ T cells in promoting sterile immunity against blood stage malaria. This is because PD-1 mediates up to a 95% reduction in numbers and functional capacity of parasite-specific CD8+ T cells, thus masking their role in protection. The role of T cell exhaustion during malaria provides an explanation for the absence of sterile immunity following the clearance of acute disease which will be relevant to future malaria-vaccine design and suggests the need for novel therapeutic solutions. This review will thus examine the role of PD-1-mediated T cell exhaustion in preventing lasting immunity against malaria.

  15. How some T cells escape tolerance induction.

    Science.gov (United States)

    Gammon, G; Sercarz, E

    1989-11-01

    A feature common to many animal models of autoimmune disease, for example, experimental allergic encephalomyelitis, experimental autoimmune myasthenia gravis and collagen-induced arthritis, is the presence of self-reactive T cells in healthy animals, which are activated to produce disease by immunization with exogenous antigen. It is unclear why these T cells are not deleted during ontogeny in the thymus and, having escaped tolerance induction, why they are not spontaneously activated by self-antigen. To investigate these questions, we have examined an experimental model in which mice are tolerant to an antigen despite the presence of antigen-reactive T cells. We find that the T cells that escape tolerance induction are specific for minor determinants on the antigen. We propose that these T cells evade tolerance induction because some minor determinants are only available in relatively low amounts after in vivo processing of the whole antigen. For the same reason, these T cells are not normally activated but can be stimulated under special circumstances to circumvent tolerance. PMID:2478888

  16. [Molecular pathogenesis of peripheral T cell lymphoma (2): extranodal NK/T cell lymphoma, nasal type, adult T cell leukemia/lymphoma and enteropathy associated T cell lymphoma].

    Science.gov (United States)

    Couronné, Lucile; Bastard, Christian; Gaulard, Philippe; Hermine, Olivier; Bernard, Olivier

    2015-11-01

    Peripheral T-cell lymphomas (PTCL) belong to the group of non-Hodgkin lymphoma and particularly that of mature T /NK cells lymphoproliferative neoplasms. The 2008 WHO classification describes different PTCL entities with varying prevalence. With the exception of histologic subtype "ALK positive anaplastic large cell lymphoma", PTCL are characterized by a poor prognosis. The mechanisms underlying the pathogenesis of these lymphomas are not yet fully understood, but development of genomic high-throughput analysis techniques now allows to extensively identify the molecular abnormalities present in tumor cells. This review aims to summarize the current knowledge and recent advances about the molecular events occurring at the origin or during the natural history of main entities of PTCL. The first part published in the October issue was focused on the three more frequent entities, i.e. angioimmunoblastic T-cell lymphoma, peripheral T-cell lymphoma, not otherwise specified, and anaplastic large cell lymphoma. The second part presented herein will describe other subtypes less frequent and of poor prognosis : extranodal NK/T-cell lymphoma, nasal type, adult T-cell leukemia/lymphoma, and enteropathy-associated T-cell lymphoma. PMID:26576610

  17. Distribution of primed T cells and antigen-loaded antigen presenting cells following intranasal immunization in mice.

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    Annalisa Ciabattini

    Full Text Available Priming of T cells is a key event in vaccination, since it bears a decisive influence on the type and magnitude of the immune response. T-cell priming after mucosal immunization via the nasal route was studied by investigating the distribution of antigen-loaded antigen presenting cells (APCs and primed antigen-specific T cells. Nasal immunization studies were conducted using the model protein antigen ovalbumin (OVA plus CpG oligodeoxynucleotide adjuvant. Trafficking of antigen-specific primed T cells was analyzed in vivo after adoptive transfer of OVA-specific transgenic T cells in the presence or absence of fingolimod, a drug that causes lymphocytes sequestration within lymph nodes. Antigen-loaded APCs were observed in mediastinal lymph nodes, draining the respiratory tract, but not in distal lymph nodes. Antigen-specific proliferating T cells were first observed within draining lymph nodes, and later in distal iliac and mesenteric lymph nodes and in the spleen. The presence at distal sites was due to migration of locally primed T cells as shown by fingolimod treatment that caused a drastic reduction of proliferated T cells in non-draining lymph nodes and an accumulation of extensively divided T cells within draining lymph nodes. Homing of nasally primed T cells in distal iliac lymph nodes was CD62L-dependent, while entry into mesenteric lymph nodes depended on both CD62L and α4β7, as shown by in vivo antibody-mediated inhibition of T-cell trafficking. These data, elucidating the trafficking of antigen-specific primed T cells to non-draining peripheral and mucosa-associated lymph nodes following nasal immunization, provide relevant insights for the design of vaccination strategies based on mucosal priming.

  18. Microbial infection-induced expansion of effector T cells overcomes the suppressive effects of regulatory T cells via an IL-2 deprivation mechanism.

    Science.gov (United States)

    Benson, Alicia; Murray, Sean; Divakar, Prashanthi; Burnaevskiy, Nikolay; Pifer, Reed; Forman, James; Yarovinsky, Felix

    2012-01-15

    Foxp3(+) regulatory T (Treg) cells are a critical cell population that suppresses T cell activation in response to microbial and viral pathogens. We identify a cell-intrinsic mechanism by which effector CD4(+) T cells overcome the suppressive effects of Treg cells in the context of three distinct infections: Toxoplasma gondii, Listeria monocytogenes, and vaccinia virus. The acute responses to the parasitic, bacterial, and viral pathogens resulted in a transient reduction in frequency and absolute number of Treg cells. The infection-induced partial loss of Treg cells was essential for the initiation of potent Th1 responses and host protection against the pathogens. The observed disappearance of Treg cells was a result of insufficiency in IL-2 caused by the expansion of pathogen-specific CD4(+) T cells with a limited capacity of IL-2 production. Exogenous IL-2 treatment during the parasitic, bacterial, and viral infections completely prevented the loss of Treg cells, but restoration of Treg cells resulted in a greatly enhanced susceptibility to the pathogens. These results demonstrate that the transient reduction in Treg cells induced by pathogens via IL-2 deprivation is essential for optimal T cell responses and host resistance to microbial and viral pathogens. PMID:22147768

  19. Non-hematopoietic cells in lymph nodes drive memory CD8 T cell inflation during murine cytomegalovirus infection.

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    Nicole Torti

    2011-10-01

    Full Text Available During human and murine cytomegalovirus (MCMV infection an exceptionally large virus-specific CD8 T cell pool is maintained in the periphery lifelong. This anomalous response is only seen for specific subsets of MCMV-specific CD8 T cells which are referred to as 'inflationary T cells'. How memory CD8 T cell inflation is induced and maintained is unclear, though their activated phenotype strongly suggests an involvement of persistent antigen encounter during MCMV latency. To dissect the cellular and molecular requirements for memory CD8 T cell inflation, we have generated a transgenic mouse expressing an MHC class I-restricted T cell receptor specific for an immunodominant inflationary epitope of MCMV. Through a series of adoptive transfer experiments we found that memory inflation was completely dependent on antigen presentation by non-hematopoietic cells, which are also the predominant site of MCMV latency. In particular, non-hematopoietic cells selectively induced robust proliferation of inflationary CD8 T cells in lymph nodes, where a majority of the inflationary CD8 T cells exhibit a central-memory phenotype, but not in peripheral tissues, where terminally differentiated inflationary T cells accumulate. These results indicate that continuous restimulation of central memory CD8 T cells in the lymph nodes by infected non-hematopoietic cells ensures the maintenance of a functional effector CD8 T pool in the periphery, providing protection against viral reactivation events.

  20. Cutting edge: neuronal recognition by CD8 T cells elicits central diabetes insipidus.

    Science.gov (United States)

    Scheikl, Tanja; Pignolet, Béatrice; Dalard, Cécile; Desbois, Sabine; Raison, Danièle; Yamazaki, Masanori; Saoudi, Abdelhadi; Bauer, Jan; Lassmann, Hans; Hardin-Pouzet, Hélène; Liblau, Roland S

    2012-05-15

    An increasing number of neurologic diseases is associated with autoimmunity. The immune effectors contributing to the pathogenesis of such diseases are often unclear. To explore whether self-reactive CD8 T cells could attack CNS neurons in vivo, we generated a mouse model in which the influenza virus hemagglutinin (HA) is expressed specifically in CNS neurons. Transfer of cytotoxic anti-HA CD8 T cells induced an acute but reversible encephalomyelitis in HA-expressing recipient mice. Unexpectedly, diabetes insipidus developed in surviving animals. This robust phenotype was associated with preferential accumulation of cytotoxic CD8 T cells in the hypothalamus, upregulation of MHC class I molecules, and destruction of vasopressin-expressing neurons. IFN-γ production by the pathogenic CD8 T cells was necessary for MHC class I upregulation by hypothalamic neurons and their destruction. This novel mouse model, in combination with related human data, supports the concept that autoreactive CD8 T cells can trigger central diabetes insipidus. PMID:22504649

  1. P2X7 on mouse T cells: one channel, many functions

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    Björn eRissiek

    2015-05-01

    Full Text Available The P2X7 receptor is an adenosine triphosphate (ATP-gated cation channel that is expressed by several cells of the immune system. P2X7 is best known for its proinflammatory role in promoting inflammasome formation and release of mature IL-1β by innate immune cells. Mounting evidence indicates that P2X7 is also an important regulatory receptor of murine and human T cell functions. Murine T cells express a sensitive splice variant of P2X7 that can be activated either by non-covalent binding of ATP or, in the presence of nicotinamide adenine dinucleotide (NAD+, by its covalent ADP-ribosylation catalyzed by the ecto-ADP-ribosyltransferase ARTC2.2. Prolonged activation of P2X7 by either one of these pathways triggers the induction of T cell death. Conversely, lower concentrations of ATP can activate P2X7 to enhance T cell proliferation and production of IL-2. In this review we will highlight the molecular and cellular consequences of P2X7 activation on mouse T cells and its versatile role in T cell homeostasis and activation. Further, we will discuss important differences in the function of P2X7 on human and murine T cells.

  2. Immunological tolerance to muscle autoantigens involves peripheral deletion of autoreactive CD8+ T cells.

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    Emilie Franck

    Full Text Available Muscle potentially represents the most abundant source of autoantigens of the body and can be targeted by a variety of severe autoimmune diseases. Yet, the mechanisms of immunological tolerance toward muscle autoantigens remain mostly unknown. We investigated this issue in transgenic SM-Ova mice that express an ovalbumin (Ova neo-autoantigen specifically in skeletal muscle. We previously reported that antigen specific CD4(+ T cell are immunologically ignorant to endogenous Ova in this model but can be stimulated upon immunization. In contrast, Ova-specific CD8(+ T cells were suspected to be either unresponsive to Ova challenge or functionally defective. We now extend our investigations on the mechanisms governing CD8(+ tolerance in SM-Ova mice. We show herein that Ova-specific CD8(+ T cells are not detected upon challenge with strongly immunogenic Ova vaccines even after depletion of regulatory T cells. Ova-specific CD8(+ T cells from OT-I mice adoptively transferred to SM-Ova mice started to proliferate in vivo, acquired CD69 and PD-1 but subsequently down-regulated Bcl-2 and disappeared from the periphery, suggesting a mechanism of peripheral deletion. Peripheral deletion of endogenous Ova-specific cells was formally demonstrated in chimeric SM-Ova mice engrafted with bone marrow cells containing T cell precursors from OT-I TCR-transgenic mice. Thus, the present findings demonstrate that immunological tolerance to muscle autoantigens involves peripheral deletion of autoreactive CD8(+ T cells.

  3. Noncytotoxic T cell clones obtained from a human mixed leukocyte culture.

    Science.gov (United States)

    Chu, M H; Wee, S L; Bach, F H

    1990-02-01

    Peripheral blood mononuclear cells from a DQW-1 homozygous individual were cocultured with irradiated lymphoblastoid cell line from a DQW-1 homozygous unrelated donor bearing BW35-DW1 haplotype. From T cell cloning of primary and twice-stimulated mixed leukocyte cultures (MLC), 7 and 11 T cell clones were obtained respectively. None of the 18 clones showed specific cytotoxic activity against the alloantigen of the stimulator cell as well as natural killer (NK)-like activity against K562 cells. However, most T cell clones from both primary and re-stimulated MLC demonstrated moderate cytotoxic activity in lectin-dependent cell-mediated cytolysis (LDCC) assay. Screening assay for cell-mediated lympholysis (CML) performed on growing microcultures obtained from restimulated MLC cloning confirmed the non-cytotoxic status of these T cell clones by showing that 41 out of 44 growing microcultures were not cytotoxic against the stimulator cell; the other 3 clones lyzed the target cell mildly. The cells from all 5 T cell clones detected for indirect fluorescence expressed CD3 and CD4 surface markers. Taken together, the results suggested that proliferation-regulating T cell subsets or factor(s) may be generated during the course of MLCs under the present responder-stimulator combination, and may suppress the development of alloreactive cytotoxic T cells and NK-like cells. PMID:2144231

  4. The effect of immunosuppressive molecules on T-cell metabolic reprogramming.

    Science.gov (United States)

    Fernández-Ramos, Ana A; Poindessous, Virginie; Marchetti-Laurent, Catherine; Pallet, Nicolas; Loriot, Marie-Anne

    2016-08-01

    T lymphocytes undergo metabolic reprogramming to adapt to extracellular and intracellular cues. Specifically, T-cell metabolism results into ATP production, anabolism and catabolism pathways that not only support rapid cell growth and proliferation, but also differentiation and effector functions, recently referred as "immunometabolism". Quiescent naïve T cells rely on oxidative phosphorylation whereas aerobic glycolysis (Warburg effect) occurs in activated T cells (effector CD4(+) and CD8(+)). The molecular mechanisms that sense metabolic status and influence T-cell function require metabolic checkpoints including sensors of metabolic signals and transducers (Myc, HIF-1α, AMPK and mTOR). These metabolic checkpoints represent a novel therapeutic strategy for immune modulation. Interestingly, many immunosuppressive drugs including mTOR inhibitors (rapamycin), calcineurin inhibitors (tacrolimus, cyclosporine A) and inhibitors of de novo purine synthesis (6-mercaptopurine, mycophenolic acid and methotrexate) provide examples into how modulating these metabolic checkpoints can regulate T-cell activation, differentiation and function. In this Review we highlight emerging concepts about metabolic reprogramming in T-cell responses and we discuss the potential therapeutic interventions to influence T-cell fate and effector function.

  5. The growth threshold conjecture: a theoretical framework for understanding T-cell tolerance.

    Science.gov (United States)

    Arias, Clemente F; Herrero, Miguel A; Cuesta, José A; Acosta, Francisco J; Fernández-Arias, Cristina

    2015-07-01

    Adaptive immune responses depend on the capacity of T cells to target specific antigens. As similar antigens can be expressed by pathogens and host cells, the question naturally arises of how can T cells discriminate friends from foes. In this work, we suggest that T cells tolerate cells whose proliferation rates remain below a permitted threshold. Our proposal relies on well-established facts about T-cell dynamics during acute infections: T-cell populations are elastic (they expand and contract) and they display inertia (contraction is delayed relative to antigen removal). By modelling inertia and elasticity, we show that tolerance to slow-growing populations can emerge as a population-scale feature of T cells. This result suggests a theoretical framework to understand immune tolerance that goes beyond the self versus non-self dichotomy. It also accounts for currently unexplained observations, such as the paradoxical tolerance to slow-growing pathogens or the presence of self-reactive T cells in the organism.

  6. Defining the alloreactive T cell repertoire using high-throughput sequencing of mixed lymphocyte reaction culture.

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    Ryan O Emerson

    Full Text Available The cellular immune response is the most important mediator of allograft rejection and is a major barrier to transplant tolerance. Delineation of the depth and breadth of the alloreactive T cell repertoire and subsequent application of the technology to the clinic may improve patient outcomes. As a first step toward this, we have used MLR and high-throughput sequencing to characterize the alloreactive T cell repertoire in healthy adults at baseline and 3 months later. Our results demonstrate that thousands of T cell clones proliferate in MLR, and that the alloreactive repertoire is dominated by relatively high-abundance T cell clones. This clonal make up is consistently reproducible across replicates and across a span of three months. These results indicate that our technology is sensitive and that the alloreactive TCR repertoire is broad and stable over time. We anticipate that application of this approach to track donor-reactive clones may positively impact clinical management of transplant patients.

  7. Characterization of the metabolic phenotype of rapamycin-treated CD8+ T cells with augmented ability to generate long-lasting memory cells.

    Directory of Open Access Journals (Sweden)

    Shan He

    Full Text Available BACKGROUND: Cellular metabolism plays a critical role in regulating T cell responses and the development of memory T cells with long-term protections. However, the metabolic phenotype of antigen-activated T cells that are responsible for the generation of long-lived memory cells has not been characterized. DESIGN AND METHODS: Using lymphocytic choriomeningitis virus (LCMV peptide gp33-specific CD8(+ T cells derived from T cell receptor transgenic mice, we characterized the metabolic phenotype of proliferating T cells that were activated and expanded in vitro in the presence or absence of rapamycin, and determined the capability of these rapamycin-treated T cells to generate long-lived memory cells in vivo. RESULTS: Antigen-activated CD8(+ T cells treated with rapamycin gave rise to 5-fold more long-lived memory T cells in vivo than untreated control T cells. In contrast to that control T cells only increased glycolysis, rapamycin-treated T cells upregulated both glycolysis and oxidative phosphorylation (OXPHOS. These rapamycin-treated T cells had greater ability than control T cells to survive withdrawal of either glucose or growth factors. Inhibition of OXPHOS by oligomycin significantly reduced the ability of rapamycin-treated T cells to survive growth factor withdrawal. This effect of OXPHOS inhibition was accompanied with mitochondrial hyperpolarization and elevation of reactive oxygen species that are known to be toxic to cells. CONCLUSIONS: Our findings indicate that these rapamycin-treated T cells may represent a unique cell model for identifying nutrients and signals critical to regulating metabolism in both effector and memory T cells, and for the development of new methods to improve the efficacy of adoptive T cell cancer therapy.

  8. Increased expression of T-cell KV1.3 and KCa3.1 channels in the inflamed intestinal wall from patients with active ulcerative colitis

    DEFF Research Database (Denmark)

    Hansen, Lars Koch; Larsen, Dorte; Sadda, Veeranjaneyulu;

    INTRODUCTION: T-cell KV1.3 and KCa3.1 channels have been proposed to be important effector proteins during T-cell activation and also in autoimmune disease by controlling T-cell motility, cytokine production, and proliferation. The role of KV1.3 channels in ulcerative colitis (UC) has not been...... fashion in UC patients and may point to an increased infiltration and activity of effector T-cells and effector memory T-cells in UC. These markers could be predictive of progression and for adjusting individual immune suppressive treatments....

  9. Cord Blood Derived CD4+CD25high T Cells Become Functional Regulatory T Cells upon Antigen Encounter

    Science.gov (United States)

    Mayer, Elisabeth; Bannert, Christina; Gruber, Saskia; Klunker, Sven; Spittler, Andreas; Akdis, Cezmi A.

    2012-01-01

    Background: Upon antigen exposure, cord blood derived T cells respond to ubiquitous environmental antigens by high proliferation. To date it remains unclear whether these “excessive” responses relate to different regulatory properties of the putative T regulatory cell (Treg) compartment or even expansion of the Treg compartment itself. Methods: Cord blood (>37 week of gestation) and peripheral blood (healthy controls) were obtained and different Treg cell subsets were isolated. The suppressive potential of Treg populations after antigen exposure was evaluated via functional inhibition assays ([3H]thymidine incorporation assay and CFSE staining) with or without allergen stimulation. The frequency and markers of CD4+CD25highFoxP3+ T cells were characterized by mRNA analysis and flow cytometry. Results: Cord blood derived CD4+CD25high cells did not show substantial suppressor capacity upon TCR activation, in contrast to CD4+CD25high cells freshly purified from adult blood. This could not be explained by a lower frequency of FoxP3+CD4+CD25highcells or FOXP3 mRNA expression. However, after antigen-specific stimulation in vitro, these cells showed strong proliferation and expansion and gained potent suppressive properties. The efficiency of their suppressive capacity can be enhanced in the presence of endotoxins. If T-cells were sorted according to their CD127 expression, a tiny subset of Treg cells (CD4+CD25+CD127low) is highly suppressive even without prior antigen exposure. Conclusion: Cord blood harbors a very small subset of CD4+CD25high Treg cells that requires antigen-stimulation to show expansion and become functional suppressive Tregs. PMID:22272233

  10. 神经髓鞘及脱脂神经髓鞘诱导多发性硬化T淋巴细胞系对神经髓鞘成分增殖反应%Proliferations of T cell lines towards neural myelin sheath components in multiple sclerosis induced by neural myelin sheath and delipidated neural myelin sheath

    Institute of Scientific and Technical Information of China (English)

    董万利; 高晓夏; 程庆璋; 方琪; 赵红茹

    2005-01-01

    脂后,T淋巴细胞针对自身神经髓鞘产生自身免疫反应,MBP和PLP及其多肽片段均可触发MS或使其病情加重.支持MS的自身免疫病理机制假说.%BACKGROUND: Multiple sclerosis(MS) is a chronic autoimmune disease induced by the interaction between genetic and environmental factors. Its pathogen and the mechanism of the relapse and remission m the course of the disease are still unknown. Most of the MS research centers are looking for the pathogenic polypeptide epitope in proteolipid protein(PLP), myelin sheath basic protein (MBP) and oligodendrocyte glycoprotein (MOG) OBJECTIVE: To compare the proliferation of T cell lines(TCL) in MS induced by myelin sheath and delipidated myelin sheath towards 11 components of myelin sheath to mainly search the possible pathogenic polypeptide epitope in PLP, and investigate the possible effects of abnormal dcgrease in myelin sheath.DESIGN: A case-controlled trial.SETTING: Department of neurology in a hospital of a university.PARTICIPANTS: Mononuclear cells(MNC) of 16 MS cases(clinical relapsing-remitting type, patients did not receive any immunosuppresant for at least 3 months when their peripheral blood samples were taken) and 12 HLA-DR15 healthy volunteers were furnished by Dr. Trotter JL of MS Research Center of Washington University from the cell database.INTERVENTIONS: MS-TCL and normal TCL were induced twice by stimulation with myelin sheath and delipidated myelin sheath in vitro by cell culture in vitro. TCL proliferation was tested by 11 antigens including PLP,MBP, M87-106, P30-49, P40-60, P89-106, P95-117, P117-137,P139-151, P178-191, and P185-206.MAIN OUTCOME MEASURES: Difference of scintillation counting in every minute of every well, and the stimulative index of each well were calculated, and the mean wells with positive proliferation of TCL towards each antigen were confirmed as well.RESULTS: The general specific proliferation towards myelin sheath antigens was bigger in MS group than

  11. Activation of resting human T cells requires prolonged stimulation of protein kinase C

    Energy Technology Data Exchange (ETDEWEB)

    Berry, N.; Ase, K.; Kishimoto, A.; Nishizuka, Y. (Kobe Univ. School of Medicine (Japan))

    1990-03-01

    Purified resting human T cells can be induced to express the {alpha} subunit of the interleukin 2 receptor and to proliferate by treatment with 12-0-tetradecanoylphorbol-13-acetate plus ionomycin but not with 1,2-dioctanoylglycerol plus ionomycin. Determination of the translocation of protein kinase C showed that 12-0-tetradecanoylphorbol-13-acetate plus ionomycin caused a prolonged membrane association of the enzyme for more than 4 hr, whereas 1,2-dioctanoylglycerol plus ionomycin induced a transient membrane association, which was maximal at 20 min. Delivery of multiple additions of 1,2-dioctanoylglycerol plus ionomycin to the T cells resulted in progressively increased expression of the {alpha} subunit of the interleukin 2 receptor and proliferation commensurate with the number of multiple additions delivered, suggesting that prolonged protein kinase C activity is required for T-cell activation.

  12. The role of class I histocompatibility antigens in the regulation of T-cell activation.

    OpenAIRE

    Dasgupta, J D; Cemach, K; Dubey, D P; Yunis, E J; Amos, D. B.

    1987-01-01

    Class I major histocompatibility antigens in humans (HLA antigens) were found to participate in the regulation of T-cell activation and proliferation induced by phytohemagglutinin. W6/32, a monomorphic antibody directed against class I HLA-A,B,C antigens, significantly inhibited the phytohemagglutinin-induced cell proliferation of peripheral blood lymphocytes. Almost complete suppression of cell activation was achieved on a subfraction of peripheral blood lymphocytes enriched in Mo1+ monocyte...

  13. Transcriptional Analysis of T Cells Resident in Human Skin

    OpenAIRE

    Jane Li; Moshe Olshansky; Carbone, Francis R.; Ma, Joel Z.

    2016-01-01

    Human skin contains various populations of memory T cells in permanent residence and in transit. Arguably, the best characterized of the skin subsets are the CD8(+) permanently resident memory T cells (TRM) expressing the integrin subunit, CD103. In order to investigate the remaining skin T cells, we isolated skin-tropic (CLA(+)) helper T cells, regulatory T cells, and CD8(+) CD103(-) T cells from skin and blood for RNA microarray analysis to compare the transcriptional profiles of these grou...

  14. Regulatory T-cells and autoimmunity.

    LENUS (Irish Health Repository)

    Ni Choileain, Niamh

    2012-02-03

    Approximately 20% of the population is affected by autoimmune or inflammatory diseases mediated by an abnormal immune response. A characteristic feature of autoimmune disease is the selective targeting of a single cell type, organ or tissue by certain populations of autoreactive T-cells. Examples of such diseases include rheumatoid arthritis, insulin-dependent diabetes mellitus, and systemic lupus erythematosus (SLE), all of which are characterized by chronic inflammation, tissue destruction and target organ malfunction. Although strong evidence links most autoimmune diseases to specific genes, considerable controversy prevails regarding the role of regulatory T-cell populations in the disease process. These cells are now also believed to play a key role in mediating transplantation tolerance and inhibiting the induction of tumor immunity. Though the concept of therapeutic immune regulation aimed at treating autoimmune pathology has been validated in many animal models, the development of strategies for the treatment of human autoimmune disorders remains in its infancy. The main obstacles to this include the conflicting findings of different model systems, as well as the contrasting functions of regulatory T-cells and cytokines involved in the development of such disorders. This review examines the role of regulatory T-cells in the pathogenesis of autoimmunity and describes the therapeutic potential of these cells for the prevention of immune-mediated pathologies in the future. Although much remains to be learned about such pathologies, a clearer understanding of the mechanisms by which regulatory T-cells function will undoubtedly lead to exciting new possibilities for immunotherapeutics.

  15. Expression of TIA-1 and TIA-2 in T cell malignancies and T cell lymphocytosis.

    Science.gov (United States)

    Matutes, E; Coelho, E; Aguado, M J; Morilla, R; Crawford, A; Owusu-Ankomah, K; Catovsky, D

    1996-01-01

    OBJECTIVE: To investigate the reactivity with TIA-1 and TIA-2, two monoclonal antibodies that recognise, respectively, granular structures in T lymphocytes and the T cell receptor chain in cells from a variety of T cell disorders. METHODS: Cytoplasmic staining with TIA-1 and TIA-2 was carried out by the immunoalkaline phosphatase anti-alkaline phosphatase technique in 67 cases with a T cell disorder: 31 large granular lymphocyte (LGL) leukaemia, nine T-prolymphocytic leukaemia (T-PLL), five Sezary syndrome, four peripheral T cell lymphoma (PTCL), 13 T cell lymphocytosis, and five T-acute lymphoblastic leukaemia (T-ALL). All had over 75% abnormal T cells which were CD2+, CD3+, CD5+, CD7+, and negative with B cell markers. RESULTS: TIA-1 was positive in 77% cases of LGL leukaemia and half of the PTCL and T-ALL, whereas it was negative in all Sezary syndrome and most T-PLL (8/9) and reactive T-lymphocytosis (10/13). In LGL leukaemia, TIA-1 was positive irrespective of the membrane phenotype, whether CD8+, CD4- or CD4+, CD8-, and was more often positive in cases where cells were CD16+, CD56+, or CD57+. TIA-2 was positive in 60% of cases encompassing all diagnostic types of T cell disorder. There was no correlation between TIA-2 expression and that of other T cell markers, activation antigens, and natural killer markers. CONCLUSIONS: The pattern of TIA-1 expression in T cell malignancies may help in the differential diagnosis among LGL leukaemia (high expression), T cell lymphocytosis and other T cell diseases (low expression). As TIA-2 is expressed in over 95% mature T lymphocytes and thymic cells, its assessment may be useful to demonstrate aberrant phenotypes which can be exploited for detecting minimal residual disease. Images PMID:8655683

  16. The ER membrane-anchored ubiquitin ligase Hrd1 is a positive regulator of T-cell immunity

    Science.gov (United States)

    Xu, Yuanming; Zhao, Fang; Qiu, Quan; Chen, Kun; Wei, Juncheng; Kong, Qingfei; Gao, Beixue; Melo-Cardenas, Johanna; Zhang, Bin; Zhang, Jinping; Song, Jianxun; Zhang, Donna D.; Zhang, Jianing; Fan, Yunping; Li, Huabin; Fang, Deyu

    2016-01-01

    Identification of positive regulators of T-cell immunity induced during autoimmune diseases is critical for developing novel therapies. The endoplasmic reticulum resident ubiquitin ligase Hrd1 has recently emerged as a critical regulator of dendritic cell antigen presentation, but its role in T-cell immunity is unknown. Here we show that genetic deletion of Hrd1 in mice inhibits T-cell proliferation, production of IL-2, and differentiation of Th1 and Th17 cells, and consequently protects mice from experimental autoimmune encephalomyelitis. Hrd1 facilitates T-cell proliferation by the destruction of cyclin-dependent kinase inhibitor p27kip1, and deletion of p27kip1 in Hrd1-null T-cells rescues proliferative capacity but not the production of cytokines, including IL-2, IFN-γ and IL-17. T-cell expression of Hrd1 is higher in patients with multiple sclerosis than in healthy individuals, and knockdown of Hrd1 in human CD4+ T cells inhibits activation and differentiation to Th1 and Th17 cells. Our study identifies Hrd1 as a previously unappreciated positive regulator of T cells and implies that Hrd1 is a potential therapeutic target for autoimmune diseases. PMID:27417417

  17. Calpain 4 is not necessary for LFA-1-mediated function in CD4+ T cells.

    Directory of Open Access Journals (Sweden)

    Sarah A Wernimont

    Full Text Available BACKGROUND: T cell activation and immune synapse formation require the appropriate activation and clustering of the integrin, LFA-1. Previous work has reported that the calpain family of calcium-dependent proteases are important regulators of integrin activation and modulate T cell adhesion and migration. However, these studies have been limited by the use of calpain inhibitors, which have known off-target effects. METHODOLOGY/PRINCIPAL FINDINGS: Here, we used a LoxP/CRE system to specifically deplete calpain 4, a small regulatory calpain subunit required for expression and activity of ubiquitously expressed calpains 1 and 2, in CD4+ T cells. CD4+ and CD8+ T cells developed normally in Capn4(F/F:CD4-CRE mice and had severely diminished expression of Calpain 1 and 2, diminished talin proteolysis and impaired casein degradation. Calpain 4-deficient T cells showed no difference in adhesion or migration on the LFA-1 ligand ICAM-1 compared to control T cells. Moreover, there was no impairment in conjugation between Capn4(F/F:CD4-CRE T cells and antigen presenting cells, and the conjugates were still capable of polarizing LFA-1, PKC-theta and actin to the immune synapse. Furthermore, T cells from Capn4(F/F:CD4-CRE mice showed normal proliferation in response to either anti-CD3/CD28 coated beads or cognate antigen-loaded splenocytes. Finally, there were no differences in the rates of apoptosis following extrinsic and intrinsic apoptotic stimuli. CONCLUSION/SIGNIFICANCE: Our findings demonstrate that calpain 4 is not necessary for LFA-1-mediated adhesion, conjugation or migration. These results challenge previous reports that implicate a central role for calpains in the regulation of T cell LFA-1 function.

  18. CD69 expression on a-gliadin-specific T cells in coeliac disease

    Directory of Open Access Journals (Sweden)

    S Perticarari

    2009-12-01

    Full Text Available Coeliac disease (CD is a T-cell mediated immunological disease of the small intestine which is triggered in susceptible individuals by ingestion of gluten. The pathogenic mechanism of coeliac disease, and the role that a-gliadin specific T cells play in mucosal lesions and their involvement in peripheral blood is not yet explained at all. Previous studies have reported proliferative response to a-gliadin measured with the classic assay of 3HTdR incorporation. We analysed the activation antigen CD69 on T cells from CD patients and normal individuals following stimulation with a-gliadin and different antigens (tetanus toxoid, peptides unrelated to gliadin and PHA. CD69 coexpression with T cell CD3+ and proliferation marker Ki67 was evaluated with time. CD69 coexpression with T cell CD3+, CD4+ and CD8+ was also evaluated. It was found that peripheral blood mononuclear cells (PBMC of coeliac patients increased their percentage of CD69 positive T cells when stimulated with a-gliadin, in comparison with cells from controls. Significant T cell activation was found only in subjects not treated with the gluten free diet; a positive response was found also in two coeliac patients with selective IgA deficiency, anti-endomisium negative, without circulat- ing IgA anti a-gliadin or anti-tissue transglutaminase antibodies. The CD69 expression after stimulation was compared with the standard method of 3HTdR incorporation. Our data show that CD69 expression is useful to asses a specific T cell response to a-gliadin in coeliac disease. in a very short time. Moreover, the method allows to investigate T cell response at the lymphocyte subsets level, which represents a useful tool in the diagnosis of coeliac disease.

  19. The novel chicken interleukin 26 protein is overexpressed in T cells and induces proinflammatory cytokines.

    Science.gov (United States)

    Truong, Anh Duc; Park, Boyeong; Ban, Jihye; Hong, Yeong Ho

    2016-01-01

    In the present study, we describe the cloning and functional characterization of chicken interleukin 26 (ChIL-26). ChIL-26, a member of the IL-10 cytokine family, induces the production of proinflammatory cytokines by T cells. The ChIL-26 cDNA encodes an 82-amino-acid protein whose amino acid sequence has 22.63, 46.31 and 43.15% homology with human IL-26, pig IL-26 and canary IL-26, respectively. ChIL-26 signals through a heterodimeric receptor complex composed of the IL-20R1 and IL-10R2 chains, which are expressed primarily in the CU91 T cell line as well as CD4(+) and CD8(+) T cells. Recombinant ChIL-26 protein induced Th1 cytokines (IL-16 and IFN-γ), Th2 cytokines (IL-4, IL-6 and IL-10), Th17 cytokines (IL-17A, IL-17D, and IL-17F), and chemokine transcripts (mainly CCL3, CCL4, CCL5, CCL20 and CXCL13) in the CU91 T cell line and in CD4(+) and CD8(+) T cells, however IL-18 was not expressed in the CU91 T cell line. Taken together, the data demonstrates that T cells express the functional ChIL-26 receptor complex and that ChIL-26 modulates T cell proliferation and proinflammatory gene expression. To the best of our knowledge, this is the first report of cloned ChIL-26. We evaluated its functional roles, particularly in the pathogenic costimulation of T cells, which may be significantly associated with the induction of cytokines. PMID:27312894

  20. Grb2 Is Important for T Cell Development, Th Cell Differentiation, and Induction of Experimental Autoimmune Encephalomyelitis.

    Science.gov (United States)

    Radtke, Daniel; Lacher, Sonja M; Szumilas, Nadine; Sandrock, Lena; Ackermann, Jochen; Nitschke, Lars; Zinser, Elisabeth

    2016-04-01

    The small adaptor protein growth factor receptor-bound protein 2 (Grb2) modulates and integrates signals from receptors on cellular surfaces in inner signaling pathways. In murine T cells, Grb2 is crucial for amplification of TCR signaling. T cell-specific Grb2(fl/fl) Lckcre(tg) Grb2-deficient mice show reduced T cell numbers due to impaired negative and positive selection. In this study, we found that T cell numbers in Grb2(fl/fl) CD4cre(tg) mice were normal in the thymus and were only slightly affected in the periphery. Ex vivo analysis of CD4(+) Th cell populations revealed an increased amount of Th1 cells within the CD4(+) population of Grb2(fl/fl) CD4cre(tg) mice. Additionally, Grb2-deficient T cells showed a greater potential to differentiate into Th17 cells in vitro. To test whether these changes in Th cell differentiation potential rendered Grb2(fl/fl) CD4cre(tg) mice more prone to inflammatory diseases, we used the murine Th1 cell- and Th17 cell-driven model of experimental autoimmune encephalomyelitis (EAE). In contrast to our expectations, Grb2(fl/fl) CD4cre(tg) mice developed a milder form of EAE. The impaired EAE disease can be explained by the reduced proliferation rate of Grb2-deficient CD4(+) T cells upon stimulation with IL-2 or upon activation by allogeneic dendritic cells, because the activation of T cells by dendritic cells and the subsequent T cell proliferation are known to be crucial factors for the induction of EAE. In summary, Grb2-deficient T cells show defects in T cell development, increased Th1 and Th17 cell differentiation capacities, and impaired proliferation after activation by dendritic cells, which likely reduce the clinical symptoms of EAE.

  1. Change and significance of Ca2+ concentration in proliferation of HEK293 cells induced by angiotensin Ⅱ%血管紧张素Ⅱ诱导HEK293细胞增殖中Ca2+的变化及意义

    Institute of Scientific and Technical Information of China (English)

    邱国莹; 纪泽泉

    2012-01-01

    Objective: To establish proliferation models of human embryonic kidney 293 (HEK293) cells by angiotensin II , detect the effect of proliferation, Ca2+ concentration change, and expression of TRPC6, and observe the intervention effect of Losartan. Methods: Different concentrations of angiotensin II (10-8 mol/L, 10 -7 mol/L, 10-6 mol/L, and 10 -5mol/L) were used to induce HEK293 cells, MTT method and trypan blue staining were used to detect proliferation and activity of HEK293 cells at 0, 6, 12, 24, and 48 hours to confirm the optimal concentration and opportunity to construct proliferation model. After intervention with Losartan for 24 hours, confocal laser scanning microscope was used to detect the change of Ca2+ concentration, RT - PCR and Western blot were used to detect the expression of TRPC6. Results; After inducing HEK293 cells with 10-6 mol/L angiotensin II for 24 hours, cell proliferation and increase of Ca2+ concentration increased obviously, after intervention with Losartan, cell proliferation and increase of Ca 2+ concentration decreased significantly. The expression of TRPC6 was too weak to detect in cytomembrane or cytoplasm. Conclusion; Proliferation of HEK293 cells induced by angiotensin Ⅱ was correlated with increase of Ca2+ concentration, showing a certain time - and dose - dependent manner. Inhibition of cell proliferation and decrease of Ca2+ concentration after intervention of Losartan was correlated with AT1R. TRPC6 didnt express in HEK293 cells, which can be used to further research the relationship between exogenous TRPC6 and change of Ca2+ concentration.%目的:建立血管紧张素Ⅱ( AngⅡ)诱导人胚肾细胞(HEK293)增殖模型,检测增殖效果与Ca2+变化及TR-PC6的表达,并观察氯沙坦(Losartan)的干预作用.方法:用不同浓度AngⅡ( 10 -8 mol/L、10 -7 mol/L、10 -6 mol/L、10-5mol/L)诱导细胞,在不同时间(0h、6h、12h、24 h、48 h),采用MTr法及台盼蓝法检测细胞增殖及活性,确定最适浓度

  2. CD26 surface molecule involvement in T cell activation and lymphokine synthesis in rheumatoid and other inflammatory synovitis.

    Science.gov (United States)

    Gerli, R; Muscat, C; Bertotto, A; Bistoni, O; Agea, E; Tognellini, R; Fiorucci, G; Cesarotti, M; Bombardieri, S

    1996-07-01

    T cell surface expression and the functional role of CD26 antigen (Ag), a surface ectoenzyme involved in T cell activation and migration across the extracellular matrix, were analyzed in the peripheral blood (PB) and synovial fluid (SF) from patients with inflammatory arthritides. CD26 membrane expression on T cells was detected by cytofluorometry using two different monoclonal antibodies, anti-Ta1 and anti-1F7, while cell proliferation and both IL-2 and IFN-gamma production were evaluated in anti-CD3- or anti-CD2-stimulated cell cultures after Ag surface modulation with anti-1F7. The results showed that Ta1 and 1F7 Ag expression were increased on T cells from PB of patients with active, but not inactive, rheumatoid arthritis (RA). Most SF T cells from RA or other inflammatory arthritides displayed the memory marker CD45R0 and the Ta1 Ag, but lacked the 1F7 molecule. In addition, in vitro 1F7 modulation, which enhanced RA PB T cell proliferation and both IL-2 and IFN-gamma synthesis, did not synergize with anti-CD3 or anti-CD2 in inducing IL-2-dependent activation of SF T cells, but reduced IFN-gamma production. A spontaneous reappearance of 1F7 Ag on the SF T cell surface was seen after 2-5 days in culture. Phorbol myristate acetate, able to accelerate its reexpression, also restored a normal response of SF T cells to anti-1F7 comitogenic effects. These data confirm a role of the CD26 surface molecule in regulating T cell activation and lymphokine synthesis. This observation may have important implications in the regulation of T cell activity at the joint level during chronic inflammatory processes. PMID:8674237

  3. T-cell responses in malaria

    DEFF Research Database (Denmark)

    Hviid, L; Jakobsen, P H; Abu-Zeid, Y A;

    1992-01-01

    Malaria is caused by infection with protozoan parasites of the genus Plasmodium. It remains one of the most severe health problems in tropical regions of the world, and the rapid spread of resistance to drugs and insecticides has stimulated intensive research aimed at the development of a malaria...... vaccine. Despite this, no efficient operative vaccine is currently available. A large amount of information on T-cell responses to malaria antigens has been accumulated, concerning antigens derived from all stages of the parasite life cycle. The present review summarizes some of that information, and...... discusses factors affecting the responses of T cells to malaria antigens....

  4. Vitamin D controls T cell antigen receptor signaling and activation of human T cells

    DEFF Research Database (Denmark)

    von Essen, Marina Rode; Kongsbak-Wismann, Martin; Schjerling, Peter;

    2010-01-01

    Phospholipase C (PLC) isozymes are key signaling proteins downstream of many extracellular stimuli. Here we show that naive human T cells had very low expression of PLC-gamma1 and that this correlated with low T cell antigen receptor (TCR) responsiveness in naive T cells. However, TCR triggering...... led to an upregulation of approximately 75-fold in PLC-gamma1 expression, which correlated with greater TCR responsiveness. Induction of PLC-gamma1 was dependent on vitamin D and expression of the vitamin D receptor (VDR). Naive T cells did not express VDR, but VDR expression was induced by TCR...... signaling via the alternative mitogen-activated protein kinase p38 pathway. Thus, initial TCR signaling via p38 leads to successive induction of VDR and PLC-gamma1, which are required for subsequent classical TCR signaling and T cell activation....

  5. Chimeric Antigen Receptor T Cell (Car T Cell Therapy In Hematology

    Directory of Open Access Journals (Sweden)

    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.

  6. TLR2 engagement on CD4(+) T cells enhances effector functions and protective responses to Mycobacterium tuberculosis.

    Science.gov (United States)

    Reba, Scott M; Li, Qing; Onwuzulike, Sophia; Ding, Xuedong; Karim, Ahmad F; Hernandez, Yeritza; Fulton, Scott A; Harding, Clifford V; Lancioni, Christina L; Nagy, Nancy; Rodriguez, Myriam E; Wearsch, Pamela A; Rojas, Roxana E

    2014-05-01

    We have previously demonstrated that mycobacterial lipoproteins engage TLR2 on human CD4(+) T cells and upregulate TCR-triggered IFN-γ secretion and cell proliferation in vitro. Here we examined the role of CD4(+) T-cell-expressed TLR2 in Mycobacterium tuberculosis (MTB) Ag-specific T-cell priming and in protection against MTB infection in vivo. Like their human counterparts, mouse CD4(+) T cells express TLR2 and respond to TLR2 costimulation in vitro. This Th1-like response was observed in the context of both polyclonal and Ag-specific TCR stimulation. To evaluate the role of T-cell TLR2 in priming of CD4(+) T cells in vivo, naive MTB Ag85B-specific TCR transgenic CD4(+) T cells (P25 TCR-Tg) were adoptively transferred into Tlr2(-/-) recipient C57BL/6 mice that were then immunized with Ag85B and with or without TLR2 ligand Pam3 Cys-SKKKK. TLR2 engagement during priming resulted in increased numbers of IFN-γ-secreting P25 TCR-Tg T cells 1 week after immunization. P25 TCR-Tg T cells stimulated in vitro via TCR and TLR2 conferred more protection than T cells stimulated via TCR alone when adoptively transferred before MTB infection. Our findings indicate that TLR2 engagement on CD4(+) T cells increases MTB Ag-specific responses and may contribute to protection against MTB infection.

  7. Antigen availability determines CD8⁺ T cell-dendritic cell interaction kinetics and memory fate decisions.

    Science.gov (United States)

    Henrickson, Sarah E; Perro, Mario; Loughhead, Scott M; Senman, Balimkiz; Stutte, Susanne; Quigley, Michael; Alexe, Gabriela; Iannacone, Matteo; Flynn, Michael P; Omid, Shaida; Jesneck, Jonathan L; Imam, Sabrina; Mempel, Thorsten R; Mazo, Irina B; Haining, W Nicholas; von Andrian, Ulrich H

    2013-09-19

    T cells are activated by antigen (Ag)-bearing dendritic cells (DCs) in lymph nodes in three phases. The duration of the initial phase of transient, serial DC-T cell interactions is inversely correlated with Ag dose. The second phase, characterized by stable DC-T cell contacts, is believed to be necessary for full-fledged T cell activation. Here we have shown that this is not the case. CD8⁺ T cells interacting with DCs presenting low-dose, short-lived Ag did not transition to phase 2, whereas higher Ag dose yielded phase 2 transition. Both antigenic constellations promoted T cell proliferation and effector differentiation but yielded different transcriptome signatures at 12 hr and 24 hr. T cells that experienced phase 2 developed long-lived memory, whereas conditions without stable contacts yielded immunological amnesia. Thus, T cells make fate decisions within hours after Ag exposure, resulting in long-term memory or abortive effector responses, correlating with T cell-DCs interaction kinetics. PMID:24054328

  8. Flow-cytometric measurement of CD4-8- T cells bearing T-cell receptor αβ chains, 1

    International Nuclear Information System (INIS)

    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)

  9. Purification of exosomes from rat mesenteric and peripheral lymph nodes and their effect on T cell proliferation%大鼠肠系膜淋巴结和外周淋巴结固有exosome的制备及其对T细胞增殖的影响

    Institute of Scientific and Technical Information of China (English)

    孙祯; 黄赤兵; 宋亚军; 余雪松; 贺伟峰; 陈益荣; 胡文刚; 王晋

    2013-01-01

    目的 从大鼠肠系膜淋巴结、外周淋巴结中分离纯化exosome,鉴定其对T细胞增殖的影响.方法 取出BN(RTln)大鼠的外周淋巴结及肠系膜淋巴结并研磨、离心以获得非细胞组织上清,采用超滤密度梯度离心法提取exosome.透射电镜对收集的exosome进行形态学鉴定,BCA法进行蛋白定量,SDS-PAGE电泳分离蛋白,Western blot检测IL-10的表达,并通过昆合淋巴细胞培养检测其对T细胞增殖的影响.结果 两种淋巴组织来源的非细胞组织上清均含有exosome,肠系膜淋巴结源性exosome蛋白浓度[(1.92±0.10) μg/μL]显著高于外周淋巴结源性exosome[(1.57±0.06) μg/μL,P<0.05],SDS-PAGE显示两种组织源性exosome所含蛋白种类和数量有明显差异,Western blot显示肠系膜淋巴结固有exosome中IL-10的表达显著高于外周淋巴结固有exosome,混合淋巴细胞培养结果显示肠系膜淋巴结固有exosome和外周淋巴结固有exosome对T细胞的增殖均有促进作用(P<0.05),外周淋巴结源性exosome的促增殖作用显著大于肠系膜淋巴结源性exosome(P<0.05).结论 肠系膜淋巴结、外周淋巴结均含有组织固有exosome,两种组织来源exosome有蛋白浓度和蛋白种类的差异,且均能促进淋巴细胞增殖,促进程度有显著差异.%Objective To investigate the purification methods of the exosomes derived form lymphoid tissues of rats and determine their effect on T cell proliferation. Methods The peripheral lymph nodes and mesenteric lymph nodes from BN (RT1 n) rats were separated, and their impurity were removed by centrifugation. Then, the exosomes were purified from the acellular supernatants by means of differential ultracentrifugation or ultrafiltration and sucrose gradient centrifugation, and confirmed by transmission electron microscopy. The protein expression of the exosomes was analyzed by SDS-PAGE electrophoresis. Western blot analysis was used to test the expression of IL-10. Finally

  10. Lack of suppressive CD4+CD25+FOXP3+ T cells in advanced stages of primary cutaneous T-cell lymphoma.

    Science.gov (United States)

    Tiemessen, Machteld M; Mitchell, Tracey J; Hendry, Lisa; Whittaker, Sean J; Taams, Leonie S; John, Susan

    2006-10-01

    Mycosis fungoides and its leukemic variant, Sezary syndrome, are the most common primary cutaneous T-cell lymphomas (CTCLs). In an ex vivo study, we investigated the percentage, phenotype, and suppressive function of CD4+CD25+ regulatory T cells (Tregs) from peripheral blood of CTCL patients. The percentage of Tregs did not differ significantly between patients and controls. Functional assays demonstrated a dichotomy in Treg function: in four out of 10 patients CD4+CD25+ T cells were incapable of suppressing autologous CD4+CD25- T-cell proliferation, whereas suppressive function was intact in the other six patients. Suppressive activity of Tregs inversely correlated with the peripheral blood tumor burden. T-plastin gene expression, used as a Sezary cell marker, confirmed that Sezary cells were heterogeneous for CD25 expression. Mixed lymphocyte reactions demonstrated that CD4+CD25- T cells from patients who lacked functional Tregs were susceptible to suppression by Tregs from healthy controls, and had not become suppressive themselves. Furthermore, we found reduced expression of Foxp3 in the CD4+CD25+ Tregs of these patients relative to the other six CTCL patients and controls. Our findings thus indicate a dysfunction of peripheral Tregs in certain CTCL patients, which correlates with tumor burden.