Molecular regulation of MHC class I chain-related protein A expression after HDAC-inhibitor treatment of Jurkat T cells

DEFF Research Database (Denmark)

Andresen, Lars; Jensen, Helle; Pedersen, Marianne T

2007-01-01

In this study, we characterize the molecular signal pathways that lead to MHC class I chain-related protein A (MICA) expression after histone deacetylase (HDAC)-inhibitor (HDAC-i) treatment of Jurkat T cells. Chelating calcium with BAPTA-AM or EGTA potently inhibited HDAC- and CMV-mediated MICA......1 site from position -113 to -93 relative to the mRNA start site was important for HDAC and CMV-induced promoter activity. Sp1 was subsequently shown to be important, as targeted mutation of the Sp1 binding sequence or siRNA mediated down modulation of Sp1-inhibited MICA promoter activity...

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

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

2016-01-01

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

[ABIN1 is not involved in imatinib upregulating A20 to inhibit the activation of NF-κB pathway in Jurkat T cells].

Science.gov (United States)

Chen, Qian; Wang, Senlin; Lin, Chen; Chen, Shaohua; Zhao, Xiaoling; Li, Yangqiu

2017-05-01

Objective To investigate the effect of imatinib (IM) on the expressions of A20-binding inhibitor of NF-κB1 (ABIN1) and A20 in Jurkat T cells. Methods Jurkat T cells were treated with 25, 50 and 100 nmol/L IM for 24 hours. The mRNA and protein levels of ABIN1, A20 and NF-κB were detected by real-time quantitative PCR and Western blotting. Results IM significantly inhibited both mRNA and protein levels of ABIN1 and NF-κB, but raised the mRNA and protein levels of A20; while phorbol 12-myristate 13-acetate/ionomycin increased the expression levels of ABIN1 and A20 mRNA and protein. Conclusion IM could upregulate A20 protein to inhibit the activation of NF-κB pathway in Jurkat T cells, which was independent of the ABIN1 protein.

Targeting Jurkat T Lymphocyte Leukemia Cells by an Engineered Interferon-Alpha Hybrid Molecule

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Dehai Yu

2017-06-01

Full Text Available Background/Aims: Adult T-cell leukemia/lymphoma (ATL is a very aggressive T cell malignancy that carries a poor prognosis, primarily due to its resistance to chemotherapy and to life-threatening infectious complications. Interferon-alpha (IFNα has been used in combination with the anti-retroviral drug zidovudine to treat patients with ATL. However, the efficacy of long-term therapy is significantly limited due to the systemic toxicity of IFNα. Methods: We utilized phage display library screening to identify short peptides that specifically bind to Jurkat T lymphocyte leukemia cells. By fusing the Jurkat-binding peptide to the C-terminus of IFNα, we constructed an engineered chimeric IFNα molecule (IFNP for the treatment of ATL. Results: We found that IFNP exhibited significantly higher activity than wild type IFNα in inhibiting the growth of leukemia cells and inducing cell blockage at the G0/G1 phase. The synthetic IFNP molecule exerted its antitumor activity by upregulating the downstream genes involved in the STAT1 pathway and in apoptosis. Using a cell receptor binding assay, we showed that this Jurkat-binding peptide facilitated the binding affinity of IFNα to the cell surface type I IFN receptor. Conclusion: The isolated Jurkat-binding peptide significantly potentiates the therapeutic activity of IFNα in T lymphocyte leukemia cells. The engineered IFNP molecule may prove to a novel antitumor approach in the treatment of patients with ATL.

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

Directory of Open Access Journals (Sweden)

Yang T

2016-04-01

Full Text Available Tingfang Yang,1 Shuluan Yao,2 Xianfeng Zhang,3 Yan Guo2 1Department of Pediatrics, Jining No 1 People’s Hospital, Shandong Province, People’s Republic of China; 2Department of Respiratory Medicine, Jining Medical University Affiliated Hospital, Shandong Province, People’s Republic of China; 3Department of Psychiatry, Jining Psychiatric Hospital, Shandong Province, People’s Republic of China Abstract: T-cell acute lymphoblastic leukemia (T-ALL as a prevalent hematologic malignancy is one of the most common malignant tumors worldwide in children. Andrographolide (Andro, the major active component from Andrographis paniculata, has been shown to possess antitumor activities in several types of cancer cells. However, whether Andro would inhibit T-ALL cell growth remains unclear. In this study, we investigated the cytotoxic effect of Andro on human T-ALL Jurkat cells and explored the mechanisms of cell death. Cell apoptosis was assayed by flow cytometry, and the signaling transduction for Andro was analyzed by Western blotting. The results indicated 10 µg/mL Andro could significantly induce Jurkat cells’ apoptosis, depending on the inhibition of PI3K/AKT pathway. Moreover, Andro-induced apoptosis is enhanced by AKT-selective inhibitor LY294002. ERK- or JNK-selective inhibitors PD98059 and SP600125 had no effect on Andro-induced apoptosis. In addition, p38 inhibitor SB203580 could reverse Andro-induced apoptosis in Jurkat cells. We also found that the protein expression of p-p53 and p-p38 were increased after Andro treatments. The result of an in vivo study also demonstrated Andro’s dose-dependent inhibition in subcutaneous Jurkat xenografts. In conclusion, our findings explained a novel mechanism of drug action by Andro in Jurkat cells and suggested that Andro might be developed into a new candidate therapy for T-ALL patients in the coming days. Keywords: andrographolide, PI3K, AKT, Burkitt lymphoma, Jurkat cell

Long-term in vitro, cell-type-specific genome-wide reprogramming of gene expression

International Nuclear Information System (INIS)

Hakelien, Anne-Mari; Gaustad, Kristine G.; Taranger, Christel K.; Skalhegg, Bjorn S.; Kuentziger, Thomas; Collas, Philippe

2005-01-01

We demonstrate a cell extract-based, genome-wide and heritable reprogramming of gene expression in vitro. Kidney epithelial 293T cells have previously been shown to take on T cell properties following a brief treatment with an extract of Jurkat T cells. We show here that 293T cells exposed for 1 h to a Jurkat cell extract undergo genome-wide, target cell-type-specific and long-lasting transcriptional changes. Microarray analyses indicate that on any given week after extract treatment, ∼2500 genes are upregulated >3-fold, of which ∼900 are also expressed in Jurkat cells. Concomitantly, ∼1500 genes are downregulated or repressed, of which ∼500 are also downregulated in Jurkat cells. Gene expression changes persist for over 30 passages (∼80 population doublings) in culture. Target cell-type specificity of these changes is shown by the lack of activation or repression of Jurkat-specific genes by extracts of 293T cells or carcinoma cells. Quantitative RT-PCR analysis confirms the long-term transcriptional activation of genes involved in key T cell functions. Additionally, growth of cells in suspended aggregates, expression of CD3 and CD28 T cell surface markers, and interleukin-2 secretion by 293T cells treated with extract of adult peripheral blood T cells illustrate a functional nuclear reprogramming. Therefore, target cell-type-specific and heritable changes in gene expression, and alterations in cell function, can be promoted by extracts derived from transformed cells as well as from adult primary cells

Up-regulated Ectonucleotidases in Fas-Associated Death Domain Protein- and Receptor-Interacting Protein Kinase 1-Deficient Jurkat Leukemia Cells Counteract Extracellular ATP/AMP Accumulation via Pannexin-1 Channels during Chemotherapeutic Drug-Induced Apoptosis.

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Boyd-Tressler, Andrea M; Lane, Graham S; Dubyak, George R

2017-07-01

Pannexin-1 (Panx1) channels mediate the efflux of ATP and AMP from cancer cells in response to induction of extrinsic apoptosis by death receptors or intrinsic apoptosis by chemotherapeutic agents. We previously described the accumulation of extracellular ATP /AMP during chemotherapy-induced apoptosis in Jurkat human leukemia cells. In this study, we compared how different signaling pathways determine extracellular nucleotide pools in control Jurkat cells versus Jurkat lines that lack the Fas-associated death domain (FADD) or receptor-interacting protein kinase 1 (RIP1) cell death regulatory proteins. Tumor necrosis factor- α induced extrinsic apoptosis in control Jurkat cells and necroptosis in FADD-deficient cells; treatment of both lines with chemotherapeutic drugs elicited similar intrinsic apoptosis. Robust extracellular ATP/AMP accumulation was observed in the FADD-deficient cells during necroptosis, but not during apoptotic activation of Panx1 channels. Accumulation of extracellular ATP/AMP was similarly absent in RIP1-deficient Jurkat cells during apoptotic responses to chemotherapeutic agents. Apoptotic activation triggered equivalent proteolytic gating of Panx1 channels in all three Jurkat cell lines. The differences in extracellular ATP/AMP accumulation correlated with cell-line-specific expression of ectonucleotidases that metabolized the released ATP/AMP. CD73 mRNA, and α β -methylene-ADP-inhibitable ecto-AMPase activity were elevated in the FADD-deficient cells. In contrast, the RIP1-deficient cells were defined by increased expression of tartrate-sensitive prostatic acid phosphatase as a broadly acting ectonucleotidase. Thus, extracellular nucleotide accumulation during regulated tumor cell death involves interplay between ATP/AMP efflux pathways and different cell-autonomous ectonucleotidases. Differential expression of particular ectonucleotidases in tumor cell variants will determine whether chemotherapy-induced activation of Panx1 channels

Theoretical evaluations of electro-manipulation from Jurkat T cells ...

African Journals Online (AJOL)

enoh

2012-03-01

Mar 1, 2012 ... Jurkat T cells exposed to pulsed electric fields (PEFs) ..... changes in ionic strength, surface-charge density or pH, therefore it is likely to ... loosely bound conformation. ... alone, is sufficient to trigger this protein's release (Ott et.

[Heat shock protein 90--modulator of TNFalpha-induced apoptosis of Jurkat tumor cells].

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Kaĭgorodova, E V; Riazantseva, N V; Novitskiĭ, V V; Moroshkina, A N; Belkina, M V; Iakushina, V D

2011-01-01

rTNFalpha-induced programmed death of Jurkat tumor cells cultured with 17-AAG, a selective inhibitor of heat shock protein (Hsp90), was studied by fluorescent microscopy with the use of FITC-labeled annexin V and propidium iodide. Caspase-3 and -8 activities were determined by spectrophotometry using a caspase- 3 and -8 colorimetric assay kit. It was shown that inhibition of Hsp90 leads to activation of Jurkat cell apoptosis while Hsp90 itself suppresses this process. 17-AAG enhances rTNFa-induced apoptosis of tumor cells.

Effects of ionizing radiation on expression of P21 protein in Jurkat cell line and p21 gene in thymocytes and splenocytes of mice

International Nuclear Information System (INIS)

Ni Guanying; Wu Ning; Guo Haizhuo; Jin Shunzi

2011-01-01

Objective: To investigate the effects of ionizing radiation on the expression of P21 protein in Jurkat cell line and p21 gene in thymocytes and splenocytes of mice. Methods: Flow cytometry (FCM) was used to analyze the expression of P21 protein in Jurkat cells at 12 and 24 h after irradiation to 0, 0.5, 1.0, 2.0, 4.0, and 6.0 Gy. Real-time PCR was used to detect the expression of p21 gene in thymocytes and splenocytes of mice at 4 and 24 h after irradiation to 0, 0.5, 1.0, 2.0, 4.0, and 6.0 Gy. Multi-staining was used to analyze the micronucleus rates of Rct in bone marrow. Results: The expressions of P21 protein were increased in a dose-dependent manner during 0.5-4.0 Gy (t=-24.23 - -3.96, P<0.05), but decreased at 6.0 Gy at 12 and 24 h post-irradiation (t=-11.19, -14.50, P<0.05). The expressions of p21 gene in both thymocytes and splenocytes of mice were increased in dose-dependent manner in the range of 0-6.0 Gy (including 6.0 Gy) (t=-29.96-8.80, P<0.05), and reached to the peak at 6.0 Gy at 4 and 24 h post-irradiation (t=-11.84 - -3.42, P<0.05), except thymocytes at 4 h and 1.0 Gy post-irradiation (t=-3.42, P>0.05). Conclusions: The expressions of P21 protein and p21 gene could be increased by X-ray irradiation, which shows good dose-dependent manners in certain range of dose. (authors)

DON shares a similar mode of action as the ribotoxic stress inducer anisomycin while TBTO shares ER stress patterns with the ER stress inducer Thapsigargin based on comparative gene expression profiling in Jurkat T cells

NARCIS (Netherlands)

Schmeits, P.C.J.; Katika, M.R.; Peijnenburg, A.A.C.M.; Loveren, van H.; Hendriksen, P.J.M.

2014-01-01

Previously, we studied the effects of deoxynivalenol (DON) and tributyltin oxide (TBTO) on whole genome mRNA expression profiles of human T lymphocyte Jurkat cells. These studies indicated that DON induces ribotoxic stress and both DON and TBTO induced ER stress which resulted into T-cell activation

Proteasome inhibitor carfilzomib interacts synergistically with histone deacetylase inhibitor vorinostat in Jurkat T-leukemia cells.

Science.gov (United States)

Gao, Minjie; Gao, Lu; Tao, Yi; Hou, Jun; Yang, Guang; Wu, Xiaosong; Xu, Hongwei; Tompkins, Van S; Han, Ying; Wu, Huiqun; Zhan, Fenghuang; Shi, Jumei

2014-06-01

In the present study, we investigated the interactions between proteasome inhibitor carfilzomib (CFZ) and histone deacetylase inhibitor vorinostat in Jurkat T-leukemia cells. Coexposure of cells to minimally lethal concentrations of CFZ with very low concentration of vorinostat resulted in synergistic antiproliferative effects and enhanced apoptosis in Jurkat T-leukemia cells, accompanied with the sharply increased reactive oxygen species (ROS), the striking decrease in the mitochondrial membrane potential (MMP), the increased release of cytochrome c, the enhanced activation of caspase-9 and -3, and the cleavage of PARP. The combined treatment of Jurkat cells pre-treated with ROS scavengers N-acetylcysteine (NAC) significantly blocked the loss of mitochondrial membrane potential, suggesting that ROS generation was a former event of the loss of mitochondrial membrane potential. Furthermore, NAC also resulted in a marked reduction in apoptotic cells, indicating a critical role for increased ROS generation by combined treatment. In addition, combined treatment arrested the cell cycle in G2-M phase. These results imply that CFZ interacted synergistically with vorinostat in Jurkat T-leukemia cells, which raised the possibility that the combination of carfilzomib with vorinostat may represent a novel strategy in treating T-cell Leukemia. © The Author 2014. Published by ABBS Editorial Office in association with Oxford University Press on behalf of the Institute of Biochemistry and Cell Biology, Shanghai Institutes for Biological Sciences, Chinese Academy of Sciences.

Modification and uptake of a cisplatin carbonato complex by Jurkat cells.

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Centerwall, Corey R; Tacka, Kirk A; Kerwood, Deborah J; Goodisman, Jerry; Toms, Bonnie B; Dubowy, Ronald L; Dabrowiak, James C

2006-07-01

The interactions of Jurkat cells with cisplatin, cis-[Pt(15NH3)2Cl2]1, are studied using 1H-15N heteronuclear single quantum coherence (HSQC) NMR and inductively coupled plasma mass spectrometry. We show that Jurkat cells in culture rapidly modify the monocarbonato complex cis-[Pt(15NH3)2(CO3)Cl]- (4), a cisplatin species that forms in culture media and probably also in blood. Analysis of the HSQC NMR peak intensity for 4 in the presence of different numbers of Jurkat cells reveals that each cell is capable of modifying 0.0028 pmol of 4 within approximately 0.6 h. The amounts of platinum taken up by the cell, weakly bound to the cell surface, remaining in the culture medium, and bound to genomic DNA were measured as functions of time of exposure to different concentrations of drug. The results show that most of the 4 that has been modified by the cells remains in the culture medium as a substance of molecular mass <3 kDa, which is HSQC NMR silent, and is not taken up by the cell. These results are consistent with a hitherto undocumented extracellular detoxification mechanism in which the cells rapidly modify 4, which is present in the culture medium, so it cannot bind to the cell. Because there is only a slow decrease in the amount of unmodified 4 remaining in the culture medium after 1 h, -1.1 +/- 0.4 microM h(-1), the cells subsequently lose their ability to modify 4. These observations have important implications for the mechanism of action of cisplatin.

Exposure of Jurkat cells to bis (tri-n-butyltin) oxide (TBTO) induces transcriptomics changes indicative for ER- and oxidative stress, T cell activation and apoptosis

International Nuclear Information System (INIS)

Katika, Madhumohan R.; Hendriksen, Peter J.M.; Loveren, Henk van; Peijnenburg, Ad

2011-01-01

Tributyltin oxide (TBTO) is an organotin compound that is widely used as a biocide in agriculture and as an antifouling agent in paints. TBTO is toxic for many cell types, particularly immune cells. The present study aimed to identify the effects of TBTO on the human T lymphocyte cell line Jurkat. Cells were treated with 0.2 and 0.5 μM TBTO for 3, 6, 12 and 24 h and then subjected to whole genome gene expression microarray analysis. The biological interpretation of the gene expression profiles revealed that endoplasmic reticulum (ER) stress is among the earliest effects of TBTO. Simultaneously or shortly thereafter, oxidative stress, activation of NFKB and NFAT, T cell activation, and apoptosis are induced. The effects of TBTO on genes involved in ER stress, NFAT pathway, T cell activation and apoptosis were confirmed by qRT-PCR. Activation and nuclear translocation of NFATC1 and the oxidative stress response proteins NRF2 and KEAP1 were confirmed by immunocytology. Taking advantage of previously published microarray data, we demonstrated that the induction of ER stress, oxidative stress, T cell activation and apoptosis by TBTO is not unique for Jurkat cells but does also occur in mouse thymocytes both ex vivo and in vivo and rat thymocytes ex vivo. We propose that the induction of ER stress leading to a T cell activation response is a major factor in the higher sensitivity of immune cells above other types of cells for TBTO. - Research Highlights: → The human T lymphocyte cell line Jurkat was exposed to TBTO. → Whole-genome microarray experiments were performed. → Data analysis revealed the induction of ER stress and activation of NFAT and NFKB. → Exposure to TBTO also led to T cell activation, oxidative stress and apoptosis.

Pro-apoptotic effect of Persea americana var. Hass (avocado) on Jurkat lymphoblastic leukemia cells.

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Bonilla-Porras, Angelica R; Salazar-Ospina, Andrea; Jimenez-Del-Rio, Marlene; Pereañez-Jimenez, Andres; Velez-Pardo, Carlos

2013-11-05

Abstract Context: Therapy for leukemia has a limited efficacy. There is a need to search for alternative anti-leukemia therapies. Persea americana Mill var. Hass (Lauraceae) is a tropical fruit (avocado) that might be used against cancer. Objective: To investigate whether P. americana induces death in Jurkat lymphoblastic leukemia cells. Materials and methods: Four ethanol extracts (0.1, 0.5, 1, 2 and 5 mg/mL) from avocado fruit (endocarp, whole seed, seed and leaves) were analyzed against Jurkat cells. Hydrogen peroxide generation by oxidation of 2',7'-dichlorodihydrofluorescein diacetate to the fluorescent compound 2',7'-dichlorfluorescein assay, acridine orange/ethidium bromide staining, flow cytometry analysis of annexin-V/7-amino-actinomycin, mitochondrial membrane potential and immunocytochemistry detection of transcription factor p53, caspase-3 and apoptosis-inducing factor (AIF) were evaluated. Results: Endocarp, seed, whole seed, and leaf (0.1 mg/mL) extracts induced significant apoptosis in Jurkat cells (p avocado and its therapeutic action on leukemia.

CD147 and CD98 complex-mediated homotypic aggregation attenuates the CypA-induced chemotactic effect on Jurkat T cells.

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Guo, Na; Zhang, Kui; Lv, Minghua; Miao, Jinlin; Chen, Zhinan; Zhu, Ping

2015-02-01

Homotypic cell aggregation plays important roles in physiological and pathological processes, including embryogenesis, immune responses, angiogenesis, tumor cell invasion and metastasis. CD147 has been implicated in most of these phenomena, and it was identified as a T cell activation-associated antigen due to its obvious up-regulation in activated T cells. However, the explicit function and mechanism of CD147 in T cells have not been fully elucidated. In this study, large and compact aggregates were observed in Jurkat T cells after treatment with the specific CD147 monoclonal antibody HAb18 or after the expression of CD147 was silenced by RNA interference, which indicated an inhibitory effect of CD147 in T cell homotypic aggregation. Knocking down CD147 expression resulted in a significant decrease in CD98, along with prominent cell aggregation, similar to that treated by CD98 and CD147 monoclonal antibodies. Furthermore, decreased cell chemotactic activity was observed following CD147- and CD98-mediated cell aggregation, and increased aggregation was correlated with a decrease in the chemotactic ability of the Jurkat T cells, suggesting that CD147- and CD98-mediated homotypic cell aggregation plays a negative role in T cell chemotaxis. Our data also showed that p-ERK, p-ZAP70, p-CD3ζ and p-LCK were significantly decreased in the CD147- and CD98-knocked down Jurkat T cells, which suggested that decreased CD147- and/or CD98-induced homotypic T cell aggregation and aggregation-inhibited chemotaxis might be associated with these signaling pathways. A role for CD147 in cell aggregation and chemotaxis was further indicated in primary CD4(+) T cells. Similarly, low expression of CD147 in primary T cells induced prominent cell aggregation and this aggregation attenuated primary T cell chemotactic ability in response to CypA. Our results have demonstrated the correlation between homotypic cell aggregation and the chemotactic response of T cells to CypA, and these data

Immunocytological and biochemical analysis of the mode of action of bis (tri-n-butyltin) tri-oxide (TBTO) in Jurkat cells

NARCIS (Netherlands)

Katika, M.R.; Hendriksen, P.J.M.; Ruijter, de N.C.A.; Loveren, van H.; Peijnenburg, A.A.C.M.

2012-01-01

Bis (tri-n-butyltin) oxide (TBTO) is one of the organotin compounds known to induce immunosuppression. Previously, we examined the effect of TBTO on whole-genome mRNA expression in the human T lymphocyte cell line Jurkat, which led to the hypothesis that induction of endoplasmic reticulum (ER)

Carbon nanotubes on Jurkat cells: effects on cell viability and plasma membrane potential

International Nuclear Information System (INIS)

De Nicola, Milena; Ghibelli, Lina; Bellucci, Stefano; Bellis, Giovanni De; Micciulla, Federico; Traversa, Enrico

2008-01-01

Carbon nanotubes (CNT) are one of the most novel attractive materials in nanotechnology for their potential multiple applications, including in the biomedical fields. The biocompatibility and toxicity of these novel nanomaterials are still largely unknown and a systematic study on biological interference is essential. We present a toxicological assessment of different types of CNT on the human tumor lymphocytic Jurkat cells. The carbon nanomaterials examined differ in preparation, size, contaminants and morphology: (1) CNT composed of MWCNT+SWCNT, with no metal contaminants; (2) MWCNT and (3) SWCNT, both with metal contaminants; (4) carbon black as control. The results indicate that CNT exert a dose- and time-dependent cytotoxic effect on Jurkat cells, inducing apoptotic cell death, accelerating the transition to secondary necrosis and increasing the extent of apoptosis induced by damaging agents; interestingly, CNT induce a plasma membrane hyperpolarization. These alterations are produced by all types of CNT, but contaminants and/or the size modulate the extent of such effects. Thus CNT deeply affect cell behavior, suggesting that they might play a role in inflammation, and recommending greater attention in terms of evaluation of exposure risks.

A Trichostatin A (TSA)/Sp1-mediated mechanism for the regulation of SALL2 tumor suppressor in Jurkat T cells.

Science.gov (United States)

Hepp, Matías I; Escobar, David; Farkas, Carlos; Hermosilla, Viviana; Álvarez, Claudia; Amigo, Roberto; Gutiérrez, José L; Castro, Ariel F; Pincheira, Roxana

2018-05-17

SALL2 is a transcription factor involved in development and disease. Deregulation of SALL2 has been associated with cancer, suggesting that it plays a role in the disease. However, how SALL2 is regulated and why is deregulated in cancer remain poorly understood. We previously showed that the p53 tumor suppressor represses SALL2 under acute genotoxic stress. Here, we investigated the effect of Histone Deacetylase Inhibitor (HDACi) Trichostatin A (TSA), and involvement of Sp1 on expression and function of SALL2 in Jurkat T cells. We show that SALL2 mRNA and protein levels were enhanced under TSA treatment. Both, TSA and ectopic expression of Sp1 transactivated the SALL2 P2 promoter. This transactivation effect was blocked by the Sp1-binding inhibitor mithramycin A. Sp1 bound in vitro and in vivo to the proximal region of the P2 promoter. TSA induced Sp1 binding to the P2 promoter, which correlated with dynamic changes on H4 acetylation and concomitant recruitment of p300 or HDAC1 in a mutually exclusive manner. Our results suggest that TSA-induced Sp1-Lys703 acetylation contributes to the transcriptional activation of the P2 promoter. Finally, using a CRISPR/Cas9 SALL2-KO Jurkat-T cell model and gain of function experiments, we demonstrated that SALL2 upregulation is required for TSA-mediated cell death. Thus, our study identified Sp1 as a novel transcriptional regulator of SALL2, and proposes a novel epigenetic mechanism for SALL2 regulation in Jurkat-T cells. Altogether, our data support SALL2 function as a tumor suppressor, and SALL2 involvement in cell death response to HDACi. Copyright © 2018. Published by Elsevier B.V.

Human T-cell line (Jurkat cell) encapsulation by nano-organized polyelectrolytes and their response assessment in vitro and in vivo

Energy Technology Data Exchange (ETDEWEB)

Pandey, Siddharth [Institute of Nuclear Medicine and Allied Sciences (INMAS), Stem Cell and Gene Therapy Research Group (India); Afrin, Fahrat [Jamia Hamdard, Department of Biotechnology (India); Tripathi, R. P.; Gangenahalli, Gurudutta, E-mail: gugdutta@rediffmail.com [Institute of Nuclear Medicine and Allied Sciences (INMAS), Stem Cell and Gene Therapy Research Group (India)

2013-07-15

Single living Jurkat cells have been encapsulated through polyelectrolytes nanoparticles poly(allyl amine hydrochloride) size 15.6 nm and poly(styrene-co-sulfonic acid sodium salt) size 30.2 nm, through layer by layer coating of oppositely charged plasma membrane. Confocal microscopy and scanning electron microscopy results showed complete shielding of Jurkat cells, and no changes in cell surface morphology of encapsulated cells were observed. Cell viability was not affected after encapsulation and no toxicity was found. In vivo studies demonstrated no significant changes in hematological and biochemical parameters of blood serum at day 1 and 7 in mice. Histopathological analyses of liver and spleen tissues showed nontoxic nature of prepared formulations.

NF-kappa B activity in T cells stably expressing the Tax protein of human T cell lymphotropic virus type I

International Nuclear Information System (INIS)

Lacoste, J.; Cohen, L.; Hiscott, J.

1991-01-01

The effect of constitutive Tax expression on the interaction of NF-κ B with its recognition sequence and on NF-κ B-dependent gene expression was examined in T lymphoid Jurkat cell lines (19D and 9J) stably transformed with a Tax expression vector. Tax expressing T cell lines contained a constitutive level of NF-κ B binding activity, detectable by mobility shift assay and uv cross-linking using a palindromic NF-κ B probe homologous to the interferon beta PRDII site. In Jurkat and NC2.10 induction with phorbol esters resulted in the appearance of new DNA binding proteins of 85, 75, and 54 kDa, whereas in Tax expressing cells the 85-kDa protein and a 92-kDa DNA binding protein were constitutively induced. Expression of Tax protein in 19D and 9J resulted in transcription of the endogenous NF-kappa B-dependent granulocyte-macrophage colony stimulating factor gene and increased basal level expression of transfected NF-kappa B-regulated promoters. Nonetheless transcription of both the endogenous and the transfected gene was inducible by PMA treatment. Tax expression in Jurkat T cells may alter the stoichiometry of NF-kappa B DNA binding proteins and thus change the expression of NF-kappa B-regulated promoters

Apoptosis induction in Jurkat cells and sCD95 levels in women's sera are related with the risk of developing cervical cancer

Directory of Open Access Journals (Sweden)

Bravo-Cuellar Alejandro

2008-04-01

Full Text Available Abstract Background Currently, there is clear evidence that apoptosis plays an important role in the development and progression of tumors. One of the best characterized apoptosis triggering systems is the CD95/Fas/APO-1 pathway; previous reports have demonstrated high levels of soluble CD95 (sCD95 in serum of patients with some types of cancer. Cervical cancer is the second most common cancer among women worldwide. As a first step in an attempt to design a minimally invasive test to predict the risk of developing cervical cancer in patients with precancerous lesions, we used a simple assay based on the capacity of human serum to induce apoptosis in Jurkat cells. We evaluated the relationship between sCD95 levels and the ability to induce apoptosis in Jurkat cells in cervical cancer patients and controls. Methods Jurkat cells were exposed to serum from 63 women (20 healthy volunteers, 21 with cervical intraepithelial neoplasia grade I [CIN 1] and 22 with cervical-uterine carcinoma. The apoptotic rate was measured by flow cytometry using Annexin-V-Fluos and Propidium Iodide as markers. Serum levels of sCD95 and soluble CD95 ligand (sCD95L were measured by ELISA kits. Results We found that serum from almost all healthy women induced apoptosis in Jurkat cells, while only fifty percent of the sera from women with CIN 1 induced cell death in Jurkat cells. Interestingly, only one serum sample from a patient with cervical-uterine cancer was able to induce apoptosis, the rest of the sera protected Jurkat cells from this killing. We were able to demonstrate that elimination of Jurkat cells was mediated by the CD95/Fas/Apo-1 apoptotic pathway. Furthermore, the serum levels of sCD95 measured by ELISA were significantly higher in women with cervical cancer. Conclusion Our results demonstrate that there is a strong correlation between low levels of sCD95 in serum of normal women and higher apoptosis induction in Jurkat cells. We suggest that an analysis of

Apoptosis induction in Jurkat cells and sCD95 levels in women's sera are related with the risk of developing cervical cancer

International Nuclear Information System (INIS)

Aguilar-Lemarroy, Adriana; Jave-Suarez, Luis F; Romero-Ramos, Jose E; Olimon-Andalon, Vicente; Hernandez-Flores, Georgina; Lerma-Diaz, Jose M; Ortiz-Lazareno, Pablo C; Morgan-Villela, Gilberto; Toro-Arreola, Susana del; Bravo-Cuellar, Alejandro

2008-01-01

Currently, there is clear evidence that apoptosis plays an important role in the development and progression of tumors. One of the best characterized apoptosis triggering systems is the CD95/Fas/APO-1 pathway; previous reports have demonstrated high levels of soluble CD95 (sCD95) in serum of patients with some types of cancer. Cervical cancer is the second most common cancer among women worldwide. As a first step in an attempt to design a minimally invasive test to predict the risk of developing cervical cancer in patients with precancerous lesions, we used a simple assay based on the capacity of human serum to induce apoptosis in Jurkat cells. We evaluated the relationship between sCD95 levels and the ability to induce apoptosis in Jurkat cells in cervical cancer patients and controls. Jurkat cells were exposed to serum from 63 women (20 healthy volunteers, 21 with cervical intraepithelial neoplasia grade I [CIN 1] and 22 with cervical-uterine carcinoma). The apoptotic rate was measured by flow cytometry using Annexin-V-Fluos and Propidium Iodide as markers. Serum levels of sCD95 and soluble CD95 ligand (sCD95L) were measured by ELISA kits. We found that serum from almost all healthy women induced apoptosis in Jurkat cells, while only fifty percent of the sera from women with CIN 1 induced cell death in Jurkat cells. Interestingly, only one serum sample from a patient with cervical-uterine cancer was able to induce apoptosis, the rest of the sera protected Jurkat cells from this killing. We were able to demonstrate that elimination of Jurkat cells was mediated by the CD95/Fas/Apo-1 apoptotic pathway. Furthermore, the serum levels of sCD95 measured by ELISA were significantly higher in women with cervical cancer. Our results demonstrate that there is a strong correlation between low levels of sCD95 in serum of normal women and higher apoptosis induction in Jurkat cells. We suggest that an analysis of the apoptotic rate induced by serum in Jurkat cells and the

Caspase-dependent inhibition of store-operated Ca2+ entry into apoptosis-committed Jurkat cells

International Nuclear Information System (INIS)

Onopiuk, Marta; Wierzbicka, Katarzyna; Brutkowski, Wojciech; Szczepanowska, Joanna; Zablocki, Krzysztof

2010-01-01

Activation of T-cells triggers store-operated Ca 2+ entry, which begins a signaling cascade leading to induction of appropriate gene expression and eventually lymphocyte proliferation and differentiation. The simultaneous enhancement of Fas ligand gene expression in activated cells allows the immune response to be limited by committing the activated cells to apoptosis. In apoptotic cells the store-operated calcium entry is significantly inhibited. It has been documented that moderate activation of Fas receptor may cause reversible inhibition of store-operated channels by ceramide released from hydrolyzed sphingomyelin. Here we show that activation of Fas receptor in T-cells results in caspase-dependent decrease of cellular STIM1 and Orai1 protein content. This effect may be responsible for the substantial inhibition of Ca 2+ entry into Jurkat cells undergoing apoptosis. In turn, this inhibition might prevent overloading of cells with calcium and protect them against necrosis. -- Research highlights: → Fas activation reduces STIM1 and Orai1 protein content in caspase dependent manner. → Fas activation partially reduces mitochondrial potential in caspase dependent manner. → Fas stimulation inhibits of store-operated Ca 2+ entry in caspase dependent manner. → Inhibition of Ca 2+ entry in apoptotic cells may protect them from secondary necrosis.

Site-specific integration of CAR gene into Jurkat T cells with a linear close-ended AAV-based DNA vector for CAR-T engineering.

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Zhang, Yun; Liu, Xiaomei; Zhang, Jinju; Zhang, Chun

2016-09-01

To develop a site-specific integration strategy for CAR-T engineering by using a non-viral vector dependent on adeno-associated viral (AAV) genome, which tends to be integrated into AAVS1 site with the help of its Rep proteins. AAV-dependent vectors were produced in Sf9 cells. Structural analyses revealed the vector as covalently close-ended, linear duplex molecules, which was termed "CELiD" DNA. A plasmid CMV-Rep was constructed to express the integrases Rep78 and Rep68. Jurkat cells were co-electroporated with "CELiD" DNA and plasmid CMV-Rep in order to specifically integrate CAR gene into AAVS1 site. We examined 71 stably transfected Jurkat clones by nested PCR, sequencing and southern blotting, of which 30 clones bore CAR gene within AAVS1 site. The site-specific integration efficiency was nearly 42.2 %. The AAV-dependent vector preferentially integrated CAR into AAVS1 site, which could be further used in human T cell modification and enhance the security of CAR-T therapy.

Effects of in vitro Brevetoxin Exposure on Apoptosis and Cellular Metabolism in a Leukemic T Cell Line (Jurkat

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John W. Sleasman

2008-06-01

Full Text Available Harmful algal blooms (HABs of the toxic dinoflagellate, Karenia brevis, produce red tide toxins, or brevetoxins. Significant health effects associated with red tide toxin exposure have been reported in sea life and in humans, with brevetoxins documented within immune cells from many species. The objective of this research was to investigate potential immunotoxic effects of brevetoxins using a leukemic T cell line (Jurkat as an in vitro model system. Viability, cell proliferation, and apoptosis assays were conducted using brevetoxin congeners PbTx-2, PbTx-3, and PbTx-6. The effects of in vitro brevetoxin exposure on cell viability and cellular metabolism or proliferation were determined using trypan blue and MTT (1-(4,5-dimethylthiazol-2-yl-3,5- diphenylformazan, respectively. Using MTT, cellular metabolic activity was decreased in Jurkat cells exposed to 5 - 10 μg/ml PbTx-2 or PbTx-6. After 3 h, no significant effects on cell viability were observed with any toxin congener in concentrations up to 10 μg/ml. Viability decreased dramatically after 24 h in cells treated with PbTx-2 or -6. Apoptosis, as measured by caspase-3 activity, was significantly increased in cells exposed to PbTx-2 or PbTx-6. In summary, brevetoxin congeners varied in effects on Jurkat cells, with PbTx-2 and PbTx-6 eliciting greater cellular effects compared to PbTx-3.

Nanobody-based chimeric receptor gene integration in Jurkat cells mediated by PhiC31 integrase

International Nuclear Information System (INIS)

Iri-Sofla, Farnoush Jafari; Rahbarizadeh, Fatemeh; Ahmadvand, Davoud; Rasaee, Mohammad J.

2011-01-01

The crucial role of T lymphocytes in anti-tumor immunity has led to the development of novel strategies that can target and activate T cells against tumor cells. Recombinant DNA technology has been used to generate non-MHC-restricted chimeric antigen receptors (CARs). Here, we constructed a panel of recombinant CAR that harbors the anti-MUC1 nanobody and the signaling and co-signaling moieties (CD3ζ/CD28) with different spacer regions derived from human IgG3 with one or two repeats of the hinge sequence or the hinge region of FcγRII. The PhiC31 integrase system was employed to investigate if the recombination efficiency could be recruited for high and stable expression of T cell chimeric receptor genes. The effect of nuclear localization signal (NLS) and two different promoters (CMV and CAG) on efficacy of PhiC31 integrase in human T cell lines was evaluated. The presence of integrase in combination with NLS, mediated up to 7.6 and 8.5 fold increases in CAR expression in ZCHN-attB and ZCHHN-attB cassette integrated T cells, respectively. Our results showed that highly efficient and stable transduction of the Jurkat cell line by PhiC31 integrase is a feasible modality for generating anti-cancer chimeric T cells for use in cancer immunotherapy.

Nanobody-based chimeric receptor gene integration in Jurkat cells mediated by PhiC31 integrase

Energy Technology Data Exchange (ETDEWEB)

Iri-Sofla, Farnoush Jafari [Department of Medical Biotechnology, Faculty of Medical Sciences, Tarbiat Modares University, Tehran (Iran, Islamic Republic of); Rahbarizadeh, Fatemeh, E-mail: rahbarif@modares.ac.ir [Department of Medical Biotechnology, Faculty of Medical Sciences, Tarbiat Modares University, Tehran (Iran, Islamic Republic of); Ahmadvand, Davoud [Center of Pharmaceutical Nanotechnology and Nanotoxicology, Department of Pharmaceutics and Analytical Chemistry, University of Copenhagen, Universitetsparken 2, DK-2100 Copenhagen O (Denmark); Rasaee, Mohammad J. [Department of Medical Biotechnology, Faculty of Medical Sciences, Tarbiat Modares University, Tehran (Iran, Islamic Republic of)

2011-11-01

The crucial role of T lymphocytes in anti-tumor immunity has led to the development of novel strategies that can target and activate T cells against tumor cells. Recombinant DNA technology has been used to generate non-MHC-restricted chimeric antigen receptors (CARs). Here, we constructed a panel of recombinant CAR that harbors the anti-MUC1 nanobody and the signaling and co-signaling moieties (CD3{zeta}/CD28) with different spacer regions derived from human IgG3 with one or two repeats of the hinge sequence or the hinge region of Fc{gamma}RII. The PhiC31 integrase system was employed to investigate if the recombination efficiency could be recruited for high and stable expression of T cell chimeric receptor genes. The effect of nuclear localization signal (NLS) and two different promoters (CMV and CAG) on efficacy of PhiC31 integrase in human T cell lines was evaluated. The presence of integrase in combination with NLS, mediated up to 7.6 and 8.5 fold increases in CAR expression in ZCHN-attB and ZCHHN-attB cassette integrated T cells, respectively. Our results showed that highly efficient and stable transduction of the Jurkat cell line by PhiC31 integrase is a feasible modality for generating anti-cancer chimeric T cells for use in cancer immunotherapy.

TOM1L Is Involved in a Novel Signaling Pathway Important for the IL-2 Production in Jurkat T Cells Stimulated by CD3/CD28 CoLigation

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Ahmed Elmarghani

2009-01-01

Full Text Available TOM1L (target of Myb-1 Like was identified as a binding partner for the full length and catalytically-active Lck in a yeast 2-hybrid screening assay. Here we show that in Jurkat T cells stimulated by CD3/CD28 coligation where the expression of TOM1L is reduced by lenti virus mediated-siRNA results in a dramatically lower IL-2 production. The production of IL-2 in siRNA treated cells stimulated with PMA/ionomycin was not affected indicating an involvement of TOM1L in a pathway proximal of TCR and CD28. The coexpression of Fyn with TOM1L increased the level of the phosphorylated form of Fyn indicating that TOM1L has the ability to activate Fyn. The ability of TOM1L to activate Fyn was further shown in a kinase assay using angiotensin II as a substrate. By confocal microscopy, we show that the expression of TOM1L in non-treated HeLa and SK-N-SH cells colocalizes with the mitochondrial membrane but not with lysosomal compartments or the trans-Golgi network. Furthermore, we show that the over-expression of TOM1L in Jurkat cells causes an increase of the STAT3 expression . Based on our results, we here propose that TOM1L is involved in a novel signaling pathway that is important for the IL-2 production in T cells.

[Apoptosis-modulating effects of heat shock proteins: the influence of Hsp27 chaperone on TBA Bcl-2 family proteins in Jurkat cell line].

Science.gov (United States)

Riazantseva, N V; Kaĭgorodova, E V; Maroshkina, A N; Belkina, M V; Novitskiĭ, V V

2012-01-01

The in vitro phosphorylated and non-phosphorylated Hsp27 forms concentrations and Bcl-2 proteins affected by Hsp27 inhibition were studied in Jurkat-line tumor cells and healthy donor mononuclear lymphocytes by Western blotting technique. The Hsp27 inhibition causes the increase of intracellular Bax protein concentration and the decrease of Bcl-2 level leading to an increase of apoptotic changes in Jurkat line cells.

Benzalkonium chloride (BAK induces apoptosis or necrosis, but has no major influence on the cell cycle of Jurkat cells

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Piotr Pozarowski

2011-07-01

Full Text Available Benzalkonium chloride (BAK is a cationic detergent with a very slow turnover. Because of its strong antibacterial activities, BAK is widely used especially in dentistry and ophthalmology. It is the most commonly used preservative in topical ophthalmic medications. Due to chronicity and widespread use of such treatments, BAK’s side effects are of great importance. BAK toxicity for adherent cells, probably related to its pro-oxidative activities, is time- and dose-dependent. Although lymphocytes often infiltrate superficial eye tissues, the BAK influence on them is yet to be established. The aim of this study was to check BAK cytotoxicity on T lymphocytic Jurkat line cells and to verify the suggestion that BAK can induce G2M cell blocks. A dose- and time-dependent cytotoxic effect of BAK on lymphoid cells in relatively low concentrations was shown in this study. In lower concentrations, it shows a moderate apoptotic and minimal antiproliferative effect on Jurkat cells, while in higher concentrations it shows a rapid necrotic effect. No G2M cell blocks were observed. Our findings could suggest lymphoid dysfunction during intensive, prolonged topical BAK treatment, even at dosages relatively non-toxic to epithelial eye cells. (Folia Histochemica et Cytobiologica 2011; Vol. 49, No. 2, pp. 225–230

Effect of Light Irradiation and Sex Hormones on Jurkat T Cells: 17β-Estradiol but Not Testosterone Enhances UVA-Induced Cytotoxicity in Jurkat Lymphocytes

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Michael F. Angel

2005-04-01

Full Text Available In Eastern cultures, such as India, it is traditionally recommended that women but not men cover their heads while working in the scorching sun. The purpose of this pilot study was to determine whether there was any scientific basis for this cultural tradition. We examined the differential cytotoxic effects of ultraviolet A light (UVA on an established T cell line treated with female and male sex hormones. CD4+ Jurkat T cells were plated in 96 well plates at 2 x 106 cells/ml and treated with 17β-estradiol (EST or testosterone (TE. These cells were irradiated by UVA light with an irradiance of 170 J/cm2 for 15min at a distance of 6 cm from the surface of the 96-well plate. Controls included cells not treated with hormones or UVA. The effects of EST and TE were investigated between 1 and 20 ng/mL. Cytotoxicity by fluorescein-diacetate staining and COMET assay generating single strand DNA cleavage, tail length and tail moment measurements were examined. The effect of estrogen (5ng/mL on apoptosis and its mediators was further studied using DNA laddering and western blotting for bcl-2 and p53. We found that EST alone, without UVA, enhanced Jurkat T cell survival. However, EST exhibited a dose-related cytotoxicity in the presence of UVA; up to 28% at 20 ng/ml. TE did not alter UVA-induced cytotoxicity. Since TE did not alter cell viability in the presence of UVA further damaging studies were not performed. COMET assay demonstrated the harmful effects of EST in the presence of UVA while EST without UVA had no significant effect on the nuclear damage. Apoptosis was not present as indicated by the absence of DNA laddering on agarose gel electrophoresis at 5ng/ml EST or TE ± UVA. Western blot showed that estrogen down regulated bcl-2 independently of UVA radiation while p53 was down regulated in the presence of UVA treatment. EST and TE have differential effects on UVA-induced cytotoxicity in Jurkat T-lymphocyte which suggested that women

Effects of Different Concentrations of Opium on the Secretion of Interleukin-6, Interferon-γ and Transforming Growth Factor Beta Cytokines from Jurkat Cells.

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Asadikaram, Gholamreza; Igder, Somayeh; Jamali, Zahra; Shahrokhi, Nader; Najafipour, Hamid; Shokoohi, Mostafa; Jafarzadeh, Abdollah; Kazemi-Arababadi, Mohammad

2015-01-01

The risk of infectious, autoimmune and immunodeficiency diseases and cancers rise in opioid addicts due to changes in innate and acquired immune responses. Three types of opioid receptors (К-δ-μ) are expressed on the surface of lymphocytes and mononuclear phagocytes. The present study was designed to examine the effects of different concentrations of opium on the secretion of some cytokines produced by lymphocyte cells. Jurkat cells were exposed to different concentrations of opium for periods of 6, 24 and 72 h in cell culture medium. The amount of interleukin-6 (IL-6), interferon-γ (IFN-γ) and transforming growth factor-b (TGF-β) were then measured using enzyme-linked immunosorbent assay (ELISA) method. The results showed that opium increases the secretion of IL-6 in different concentration of opium in 6 h. The amount of IFN-γ decreased in 6 h and increased in 24 h significantly compared with control. On the other hand, opium had an inhibitory effect on the TGF-β secretion in 6, 24 and 72 h. Overall, the study showed that opium stimulates pro-inflammatory and suppressed anti-inflammatory cytokine secretion in Jurkat cells. This may account for the negative effect of opium on the immune system leading to chronic inflammation and a base for many disorders in opium addicts.

Successful validation of genomic biomarkers for human immunotoxicity in Jurkat T cells in vitro.

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Schmeits, Peter C J; Shao, Jia; van der Krieken, Danique A; Volger, Oscar L; van Loveren, Henk; Peijnenburg, Ad A C M; Hendriksen, Peter J M

2015-07-01

Previously, we identified 25 classifier genes that were able to assess immunotoxicity using human Jurkat T cells. The present study aimed to validate these classifiers. For that purpose, Jurkat cells were exposed for 6 h to subcytotoxic doses of nine immunotoxicants, five non-immunotoxicants and four compounds for which human immunotoxicity has not yet been fully established. RNA was isolated and subjected to Fluidigm quantitative real time (qRT)-PCR analysis. The sensitivity, specificity and accuracy of the screening assay as based on the nine immunotoxicants and five non-immunotoxicants used in this study were 100%, 80% and 93%, respectively, which is better than the performance in our previous study. Only one compound was classified as false positive (benzo-e-pyrene). Of the four potential (non-)immunotoxicants, chlorantraniliprole and Hidrasec were classified immunotoxic and Sunset yellow and imidacloprid as non-immunotoxic. ToxPi analysis of the PCR data provided insight in the molecular pathways that were affected by the compounds. The immunotoxicants 2,3-dichloro-propanol and cypermethrin, although structurally different, affected protein metabolism and cholesterol biosynthesis and transport. In addition, four compounds, i.e. chlorpyrifos, aldicarb, benzo-e-pyrene and anti-CD3, affected genes in cholesterol metabolism and transport, protein metabolism and transcription regulation. qRT-PCR on eight additional genes coding for similar processes as defined in ToxPi analyzes, supported these results. In conclusion, the 25 immunotoxic classifiers performed very well in a screening with new non-immunotoxic and immunotoxic compounds. Therefore, the Jurkat screening assay has great promise to be applied within a tiered approach for animal free testing of human immunotoxicity. Copyright © 2014 John Wiley & Sons, Ltd.

Phytol isolated from watermelon (Citrullus lanatus) sprouts induces cell death in human T-lymphoid cell line Jurkat cells via S-phase cell cycle arrest.

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Itoh, Tomohiro; Ono, Akito; Kawaguchi, Kaori; Teraoka, Sayaka; Harada, Mayo; Sumi, Keitaro; Ando, Masashi; Tsukamasa, Yasuyuki; Ninomiya, Masayuki; Koketsu, Mamoru; Hashizume, Toshiharu

2018-05-01

The phytol isolated from watermelon (Citrullus lanatus) sprouts inhibited the growth of a human T-cell leukemia line Jurkat cell and suppressed tumor progression in a xenograft model of human lung adenocarcinoma epithelial cell line A549 in nude mice. To elucidate the mechanisms underlying the phytol-induced cell death in the present study, we examined the changes in cell morphology, DNA fragmentation, and intracellular reactive oxygen species (ROS) levels and performed flow cytometric analysis to evaluate cell cycle stage. There were no significant changes in apoptosis, autophagy, and necrosis marker in cells treated with the phytol. But, we found, for the first time, that phytol remarkably induced S-phase cell cycle arrest accompanied with intracellular ROS production. Western blot analyses showed that phytolinduced S-phase cell cycle arrest was mediated through the decreased expression of cyclins A and D and the downregulations of MAPK and PI3K/Akt. The tumor volume levels in mice treated with phytol were lower than those of non-treatment groups, and it showed very similar suppression compared with those of mice treated with cyclophosphamide. Based on the data of in vitro and in vivo studies and previous studies, we suggest phytol as a potential therapeutic compound for cancer. Copyright © 2018 Elsevier Ltd. All rights reserved.

Systems biology approach to transplant tolerance: proof of concept experiments using RNA interference (RNAi) to knock down hub genes in Jurkat and HeLa cells in vitro.

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Lwin, Wint Wah; Park, Ken; Wauson, Matthew; Gao, Qin; Finn, Patricia W; Perkins, David; Khanna, Ajai

2012-07-01

Systems biology is gaining importance in studying complex systems such as the functional interconnections of human genes [1]. To investigate the molecular interactions involved in T cell immune responses, we used databases of physical gene-gene interactions to constructed molecular interaction networks (interconnections) with R language algorithms. This helped to identify highly interconnected "hub" genes AT(1)P5C1, IL6ST, PRKCZ, MYC, FOS, JUN, and MAPK1. We hypothesized that suppression of these hub genes in the gene network would result in significant phenotypic effects on T cells and examined this in vitro. The molecular interaction networks were then analyzed and visualized with Cytoscape. Jurkat and HeLa cells were transfected with siRNA for the selected hub genes. Cell proliferation was measured using ATP luminescence and BrdU labeling, which were measured 36, 72, and 96 h after activation. Following T cell stimulation, we found a significant decrease in ATP production (P cells. However, HeLa cells showed a significant (P cell proliferation when the genes MAPK1, IL6ST, ATP5C1, JUN, and FOS were knocked down. In both Jurkat and HeLa cells, targeted gene knockdown using siRNA showed decreased cell proliferation and ATP production in both Jurkat and HeLa cells. However, Jurkat T cells and HELA cells use different hub genes to regulate activation responses. This experiment provides proof of principle of applying siRNA knockdown of T cell hub genes to evaluate their proliferative capacity and ATP production. This novel concept outlines a systems biology approach to identify hub genes for targeted therapeutics. Published by Elsevier Inc.

Pharmacologic suppression of target cell recognition by engineered T cells expressing chimeric T-cell receptors.

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Alvarez-Vallina, L; Yañez, R; Blanco, B; Gil, M; Russell, S J

2000-04-01

Adoptive therapy with autologous T cells expressing chimeric T-cell receptors (chTCRs) is of potential interest for the treatment of malignancy. To limit possible T-cell-mediated damage to normal tissues that weakly express the targeted tumor antigen (Ag), we have tested a strategy for the suppression of target cell recognition by engineered T cells. Jurkat T cells were transduced with an anti-hapten chTCR tinder the control of a tetracycline-suppressible promoter and were shown to respond to Ag-positive (hapten-coated) but not to Ag-negative target cells. The engineered T cells were then reacted with hapten-coated target cells at different effector to target cell ratios before and after exposure to tetracycline. When the engineered T cells were treated with tetracycline, expression of the chTCR was greatly decreased and recognition of the hapten-coated target cells was completely suppressed. Tetracycline-mediated suppression of target cell recognition by engineered T cells may be a useful strategy to limit the toxicity of the approach to cancer gene therapy.

Polysaccharide Isolated from Zizyphus jujuba (紅棗 Hóng Zǎo Inhibits Interleukin-2 Production in Jurkat T Cells

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Bo-Yang Hsu

2014-04-01

Full Text Available Zizyphus jujuba (紅棗 Hóng Zǎo, a traditional Chinese herb widely used in many Asian countries, has been shown to possess vital biological activities such as anti-cancer activity. The objective of this study was to evaluate the immunomodulatory effect of deproteinated polysaccharide (DP isolated from Z. jujuba. The DP isolated from Z. jujuba consisted of two polysaccharide fractions and their molecular weights (MWs were found to be 143,108 and 67,633 Da, respectively. The DP could significantly decrease interleukin (IL-2 production in phytohemagglutinin (PHA-activated Jurkat T cells in a dose-dependent manner after 48 h of incubation, with the inhibition being 47.5%, 61.2%, and 81.7% for DP concentrations of 0.75, 1.75, and 2.5 mg/ml, respectively. Thus, our study showed that DP isolated from Z. jujuba may possess anti-inflammatory activity as it could significantly reduce IL-2 production in activated Jurkat T cells.

Solanine induced apoptosis and increased chemosensitivity to Adriamycin in T-cell acute lymphoblastic leukemia cells.

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Yi, Ying-Jie; Jia, Xiu-Hong; Wang, Jian-Yong; Chen, Jie-Ru; Wang, Hong; Li, You-Jie

2018-05-01

Solanine is an alkaloid and is the main extract of the traditional Chinese herb, Solanum nigrum Linn . It has been reported that Solanine has anti-inflammatory and antitumor properties. The present study aimed to investigate the antitumor effect of Solanine in Jurkat cells and demonstrate the molecular mechanism of antitumor activity of Solanine. A Cell Counting Kit-8 assay demonstrated that Solanine inhibited the proliferation of Jurkat cells in a dose-and time-dependent manner. Cell apoptosis was measured by flow cytometry. Flow cytometry revealed that Solanine induced apoptosis in a dose-dependent manner in Jurkat cells. Reverse transcription-quantitative polymerase chain reaction demonstrated that Solanine modulated the mRNA levels of B-cell lymphoma-2 (Bcl-2) and Bcl-2-associated X protein (Bax). Additionally, Bcl-2 and Bax expression was measured using western blot analysis. Western blot analysis revealed a significant increase in the expression of Bax and decrease in the expression of Bcl-2. Solanine increased the chemosensitivity of Jurkat cells to Adriamycin. In summary, the present results indicated that the antitumor activity of Solanine was associated with inhibition of cell proliferation, induction of apoptosis and increasing cytotoxicity of Adriamycin. Therefore, Solanine may have potential as a novel agent for the treatment of acute lymphocytic leukemia.

Femtograms of Interferon-γ Suffice to Modulate the Behavior of Jurkat Cells: A New Light in Immunomodulation

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Sara Castiglioni

2017-12-01

Full Text Available Since interferon-γ (IFN-γ tunes both innate and adaptive immune systems, it was expected to enter clinical practice as an immunomodulatory drug. However, the use of IFN-γ has been limited by its dose-dependent side effects. Low-dose medicine, which is emerging as a novel strategy to treat diseases, might circumvent this restriction. Several clinical studies have proved the efficacy of therapies with a low dose of cytokines subjected to kinetic activation, while no in vitro data are available. To fill this gap, we investigated whether low concentrations, in the femtogram range, of kinetically activated IFN-γ modulate the behavior of Jurkat cells, a widely used experimental model that has importantly contributed to the present knowledge about T cell signaling. In parallel, IFN-γ in the nanogram range was used and shown to activate Signal transducer and activator of transcription (STAT-1 and then to induce suppressor of cytokine signaling-1 (SOCS-1, which inhibits downstream signaling. When added together, femtograms of IFN-γ interfere with the transduction cascade activated by nanograms of IFN-γ by prolonging the activation of STAT-1 through the downregulation of SOCS-1. We conclude that femtograms of IFN-γ exert an immunomodulatory action in Jurkat cells.

Docosahexaenoic acid and other fatty acids induce a decrease in pHi in Jurkat T-cells

OpenAIRE

Aires, Virginie; Hichami, Aziz; Moutairou, Kabirou; Khan, Naim Akhtar

2003-01-01

Docosahexaenoic acid (DHA) induced rapid (t1/2=33 s) and dose-dependent decreases in pHi in BCECF-loaded human (Jurkat) T-cells. Addition of 5-(N,N-dimethyl)-amiloride, an inhibitor of Na+/H+ exchanger, prolonged DHA-induced acidification as a function of time, indicating that the exchanger is implicated in pHi recovery.Other fatty acids like oleic acid, arachidonic acid, eicosapentaenoic acid, but not palmitic acid, also induced a fall in pHi in these cells.To assess the role of calcium in t...

STAT3-mediated constitutive expression of SOCS-3 in cutaneous T-cell lymphoma

DEFF Research Database (Denmark)

Brender, C; Nielsen, M; Kaltoft, K

2001-01-01

) obtained from affected skin from a patient with mycosis fungoides (MF) and from peripheral blood from a patient with Sezary syndrome (SS). In contrast, constitutive SOCS-3 expression is not found in the leukemic Jurkat T-cell line, the MOLT-4 acute lymphoblastic leukemia cell line, and the monocytic......, it has been hypothesized that an aberrant SOCS expression plays a role in neoplastic transformation. This study reports on a constitutive SOCS-3 expression in cutaneous T-cell lymphoma (CTCL) cell lines. SOCS-3 protein is constitutively expressed in tumor cell lines (but not in nonmalignant T cells...... leukemic cell line U937. Expression of SOCS-3 coincides with a constitutive activation of STAT3 in CTCL tumor cells, and stable transfection of CTCL tumor cells with a dominant negative STAT3 strongly inhibits SOCS-3 expression, whereas transfection with wild-type STAT3 does not. Moreover, the reduced SOCS...

Promoter, transgene, and cell line effects in the transfection of mammalian cells using PDMAEMA-based nano-stars

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Alexander Raup

2016-09-01

Full Text Available Non-viral transfection protocols are typically optimized using standard cells and reporter proteins, potentially underestimating cellular or transgene effects. Here such effects were studied for two human (Jurkat, HEK-293 and two rodent (CHO-K1, L929 cell lines and three fluorescent reporter proteins. Expression of the enhanced green fluorescent protein (EGFP was studied under the control of the human elongation factor 1 alpha promoter and three viral promoters (SV40, SV40/enhancer, CMV, that of ZsYellow1 (yellow fluorescence and mCherry (red fluorescence for the CMV promoter. Results varied with the cell line, in particular for the Jurkat cells. Pair-wise co-transfection of the CMV controlled transgenes resulted in a significant fraction of monochromatic cells (EGFP for EGFP/YFP and EGFP/RFP co-transfections, YFP in case of YFP/RFP co-transfections. Only Jurkat cells were almost incapable of expressing YFP. Dilution of the plasmid DNA with a non-expressed plasmid showed cell line dependent effects on transfection efficiency and/or expression levels.

Novel insights into the antiproliferative effects and synergism of quercetin and menadione in human leukemia Jurkat T cells.

Science.gov (United States)

Baran, Irina; Ionescu, Diana; Filippi, Alexandru; Mocanu, Maria Magdalena; Iftime, Adrian; Babes, Ramona; Tofolean, Ioana Teodora; Irimia, Ruxandra; Goicea, Alexandru; Popescu, Valentin; Dimancea, Alexandru; Neagu, Andrei; Ganea, Constanta

2014-07-01

The flavonoid quercetin and menadione (vitamin K3) are known as potent apoptogens in human leukemia Jurkat T cells. We explored some underlying mechanisms and the potential relevance of the combination quercetin-menadione for clinical applications. In acute treatments, quercetin manifested a strong antioxidant character, but induced a transient loss of Δψm, likely mediated by opening of the mitochondrial permeability transition pore. After removal of quercetin, persistent mitochondrial hyperpolarization was generated via stimulation of respiratory Complex I. In contrast, menadione-induced Δψm dissipation was only partially and transiently reversed after menadione removal. Results indicate that Ca(2+) release is a necessary event in quercetin-induced cell death and that the survival response to quercetin is delineated within 1h from exposure. Depending on dose, the two agents exhibited either antagonistic or synergistic effects in reducing clonogenicity of Jurkat cells. 24-h combinatorial regimens at equimolar concentrations of 10-15 μM, which are compatible with a clinically achievable (and safe) scheme, reduced cell viability at efficient rates. Altogether, these findings support the idea that the combination quercetin-menadione could improve the outcome of conventional leukemia therapies, and warrant the utility of additional studies to investigate the therapeutic effects of this combination in different cellular or animal models for leukemia. Copyright © 2014 Elsevier Ltd. All rights reserved.

JS-K, a nitric oxide-releasing prodrug, modulates ß-catenin/TCF signaling in leukemic Jurkat cells: evidence of an S-nitrosylated mechanism.

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Nath, Niharika; Chattopadhyay, Mitali; Pospishil, Liliya; Cieciura, Lucyna Z; Goswami, Satindra; Kodela, Ravinder; Saavedra, Joseph E; Keefer, Larry K; Kashfi, Khosrow

2010-12-01

β-Catenin is a central player of the Wnt signaling pathway that regulates cell-cell adhesion and may promote leukemia cell proliferation. We examined whether JS-K, an NO-donating prodrug, modulates the Wnt/β-catenin/TCF-4 signaling pathway in Jurkat T-Acute Lymphoblastic Leukemia cells. JS-K inhibited Jurkat T cell growth in a concentration and time-dependent manner. The IC(50)s for cell growth inhibition were 14±0.7 and 9±1.2μM at 24 and 48h, respectively. Treatment of the cells with JS-K for 24h, caused a dose-dependent increase in apoptosis from 16±3.3% at 10μM to 74.8±2% at 100μM and a decrease in proliferation. This growth inhibition was also due, in part, to alterations in the different phases of the cell cycle. JS-K exhibited a dose-dependent cytotoxicity as measured by LDH release at 24h. However, between 2 and 8h, LDH release was less than 20% for any indicated JS-K concentration. The β-catenin/TCF-4 transcriptional inhibitory activity was reduced by 32±8, 63±5, and 93±2% at 2, 10, and 25μM JS-K, respectively, based on luciferase reporter assays. JS-K reduced nuclear β-catenin and cyclin D1 protein levels, but cytosolic β-catenin expression did not change. Based on a time-course assay of S-nitrosylation of proteins by a biotin switch assay, S-nitrsolyation of nuclear β-catenin was determined to precede its degradation. A comparison of the S-nitrosylated nuclear β-catenin to the total nuclear β-catenin showed that β-catenin protein levels were degraded at 24h, while S-nitrosylation of β-catenin occurred earlier at 0-6h. The NO scavenger PTIO abrogated the JS-K mediated degradation of β-catenin demonstrating the need for NO. Copyright © 2010 Elsevier Inc. All rights reserved.

[Identification of candidate genes and expression profiles, as doping biomarkers].

Science.gov (United States)

Paparini, A; Impagnatiello, F; Pistilli, A; Rinaldi, M; Gianfranceschi, G; Signori, E; Stabile, A M; Fazio, V; Rende, M; Romano Spica, V

2007-01-01

Administration of prohibited substances to enhance athletic performance represents an emerging medical, social, ethical and legal issue. Traditional controls are based on direct detection of substances or their catabolites. However out-of-competition doping may not be easily revealed by standard analytical methods. Alternative indirect control strategies are based on the evaluation of mid- and long-term effects of doping in tissues. Drug-induced long-lasting changes of gene expression may be taken as effective indicators of doping exposure. To validate this approach, we used real-time PCR to monitor the expression pattern of selected genes in human haematopoietic cells exposed to nandrolone, insulin-like growth factor I (IGF-I) or growth hormone (GH). Some candidate genes were found significantly and consistently modulated by treatments. Nandrolone up-regulated AR, ESR2 and PGR in K562 cells, and SRD5A1, PPARA and JAK2 in Jurkat cells; IGF-I up-regulated EPOR and PGR in HL60 cells, and SRD5A1 in Jurkat; GH up-regulated SRD5A1 and GHR in K562. GATA1 expression was down-regulated in IGF-1-treated HL60, ESR2 was down-regulated in nandrolone-treated Jurkat, and AR and PGR were down-regulated in GH-treated Jurkat. This pilot study shows the potential of molecular biology-based strategies in anti-doping controls.

Lipopolysaccharide induces autotaxin expression in human monocytic THP-1 cells

International Nuclear Information System (INIS)

Li Song; Zhang Junjie

2009-01-01

Autotaxin (ATX) is a secreted enzyme with lysophospholipase D (lysoPLD) activity, which converts lysophosphatidylcholine (LPC) into lysophosphatidic acid (LPA), a bioactive phospholipid involved in numerous biological activities, including cell proliferation, differentiation, and migration. In the present study, we found that bacterial lipopolysaccharide (LPS), a well-known initiator of the inflammatory response, induced ATX expression in monocytic THP-1 cells. The activation of PKR, JNK, and p38 MAPK was required for the ATX induction. The LPS-induced ATX in THP-1 cells was characterized as the β isoform. In the presence of LPC, ATX could promote the migrations of THP-1 and Jurkat cells, which was inhibited by pertussis toxin (PTX), an inhibitor of Gi-mediated LPA receptor signaling. In summary, LPS induces ATX expression in THP-1 cells via a PKR, JNK and p38 MAPK-mediated mechanism, and the ATX induction is likely to enhance immune cell migration in proinflammatory response by regulating LPA levels in the microenvironment.

N-(1-Pyrenyl Maleimide Induces Bak Oligomerization and Mitochondrial Dysfunction in Jurkat Cells

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Pei-Rong Huang

2015-01-01

Full Text Available N-(1-pyrenyl maleimide (NPM is a fluorescent reagent that is frequently used as a derivatization agent for the detection of thio-containing compounds. NPM has been shown to display a great differential cytotoxicity against hematopoietic cancer cells. In this study, the molecular mechanism by which NPM induces apoptosis was examined. Here, we show that treatment of Jurkat cells with NPM leads to Bak oligomerization, loss of mitochondrial membrane potential (Δψm, and release of cytochrome C from mitochondria to cytosol. Induction of Bak oligomerization appears to play a critical role in NPM-induced apoptosis, as downregulation of Bak by shRNA significantly prevented NPM-induced apoptosis. Inhibition of caspase 8 by Z-IETD-FMK and/or depletion of Bid did not affect NPM-induced oligomerization of Bak. Taken together, these results suggest that NPM-induced apoptosis is mediated through a pathway that is independent of caspase-8 activation.

The content of DNA and RNA in microparticles released by Jurkat and HL-60 cells undergoing in vitro apoptosis

International Nuclear Information System (INIS)

Reich, Charles F.; Pisetsky, David S.

2009-01-01

Microparticles are small membrane-bound vesicles that are released from apoptotic cells during blebbing. These particles contain DNA and RNA and display important functional activities, including immune system activation. Furthermore, nucleic acids inside the particle can be analyzed as biomarkers in a variety of disease states. To elucidate the nature of microparticle nucleic acids, DNA and RNA released in microparticles from the Jurkat T and HL-60 promyelocytic cell lines undergoing apoptosis in vitro were studied. Microparticles were isolated from culture media by differential centrifugation and characterized by flow cytometry and molecular approaches. In these particles, DNA showed laddering by gel electrophoresis and was present in a form that allowed direct binding by a monoclonal anti-DNA antibody, suggesting antigen accessibility even without fixation. Analysis of RNA by gel electrophoresis showed intact 18s and 28s ribosomal RNA bands, although lower molecular bands consistent with 28s ribosomal RNA degradation products were also present. Particles also contained messenger RNA as shown by RT-PCR amplification of sequences for β-actin and GAPDH. In addition, gel electrophoresis showed the presence of low molecular weight RNA in the size range of microRNA. Together, these results indicate that microparticles from apoptotic Jurkat and HL-60 cells contain diverse nucleic acid species, indicating translocation of both nuclear and cytoplasmic DNA and RNA as particle release occurs during death

Benzo[a]pyrene affects Jurkat T cells in the activated state via the antioxidant response element dependent Nrf2 pathway leading to decreased IL-2 secretion and redirecting glutamine metabolism

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Murugaiyan, Jayaseelan; Rockstroh, Maxie; Wagner, Juliane [Department of Proteomics, Helmholtz-Centre for Environmental Research — UFZ, Permoserstr. 15, 04318 Leipzig (Germany); Baumann, Sven [Department of Metabolomics, Helmholtz-Centre for Environmental Research — UFZ, Permoserstr. 15, 04318 Leipzig (Germany); Schorsch, Katrin [Department of Proteomics, Helmholtz-Centre for Environmental Research — UFZ, Permoserstr. 15, 04318 Leipzig (Germany); Trump, Saskia; Lehmann, Irina [Department of Environmental Immunology, Helmholtz-Centre for Environmental Research — UFZ, Permoserstr. 15, 04318 Leipzig (Germany); Bergen, Martin von [Department of Proteomics, Helmholtz-Centre for Environmental Research — UFZ, Permoserstr. 15, 04318 Leipzig (Germany); Department of Environmental Immunology, Helmholtz-Centre for Environmental Research — UFZ, Permoserstr. 15, 04318 Leipzig (Germany); Department of Biotechnology, Chemistry and Environmental Engineering, Aalborg University, Aalborg (Denmark); Tomm, Janina M., E-mail: Janina.tomm@ufz.de [Department of Proteomics, Helmholtz-Centre for Environmental Research — UFZ, Permoserstr. 15, 04318 Leipzig (Germany)

2013-06-15

There is a clear evidence that environmental pollutants, such as benzo[a]pyrene (B[a]P), can have detrimental effects on the immune system, whereas the underlying mechanisms still remain elusive. Jurkat T cells share many properties with native T lymphocytes and therefore are an appropriate model to analyze the effects of environmental pollutants on T cells and their activation. Since environmental compounds frequently occur at low, not acute toxic concentrations, we analyzed the effects of two subtoxic concentrations, 50 nM and 5 μM, on non- and activated cells. B[a]P interferes directly with the stimulation process as proven by an altered IL-2 secretion. Furthermore, B[a]P exposure results in significant proteomic changes as shown by DIGE analysis. Pathway analysis revealed an involvement of the AhR independent Nrf2 pathway in the altered processes observed in unstimulated and stimulated cells. A participation of the Nrf2 pathway in the change of IL-2 secretion was confirmed by exposing cells to the Nrf2 activator tBHQ. tBHQ and 5 μM B[a]P caused similar alterations of IL-2 secretion and glutamine/glutamate metabolism. Moreover, the proteome changes in unstimulated cells point towards a modified regulation of the cytoskeleton and cellular stress response, which was proven by western blotting. Additionally, there is a strong evidence for alterations in metabolic pathways caused by B[a]P exposure in stimulated cells. Especially the glutamine/glutamate metabolism was indicated by proteome pathway analysis and validated by metabolite measurements. The detrimental effects were slightly enhanced in stimulated cells, suggesting that stimulated cells are more vulnerable to the environmental pollutant model compound B[a]P. - Highlights: • B[a]P affects the proteome of Jurkat T cells also at low concentrations. • Exposure to B[a]P (50 nM, 5 μM) did not change Jurkat T cell viability. • Both B[a]P concentrations altered the IL-2 secretion of stimulated cells. �

Influence of zinc deficiency on cell-membrane fluidity in Jurkat, 3T3 and IMR-32 cells.

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Verstraeten, Sandra V; Zago, M Paola; MacKenzie, Gerardo G; Keen, Carl L; Oteiza, Patricia I

2004-01-01

We investigated whether zinc deficiency can affect plasma membrane rheology. Three cell lines, human leukaemia T-cells (Jurkat), rat fibroblasts (3T3) and human neuroblastoma cells (IMR-32), were cultured for 48 h in control medium, in zinc-deficient medium (1.5 microM zinc; 1.5 Zn), or in the zinc-deficient medium supplemented with 15 microM zinc (15 Zn). The number of viable cells was lower in the 1.5 Zn group than in the control and 15 Zn groups. The frequency of apoptosis was higher in the 1.5 Zn group than in the control and 15 Zn groups. Membrane fluidity was evaluated using the 6-(9-anthroyloxy)stearic acid and 16-(9-anthroyloxy)palmitic acid probes. Membrane fluidity was higher in 1.5 Zn cells than in the control cells; no differences were observed between control cells and 15 Zn cells. The effect of zinc deficiency on membrane fluidity at the water/lipid interface was associated with a higher phosphatidylserine externalization. The higher membrane fluidity in the hydrophobic region of the bilayer was correlated with a lower content of arachidonic acid. We suggest that the increased fluidity of the membrane secondary to zinc deficiency is in part due to a decrease in arachidonic acid content and the apoptosis-related changes in phosphatidylserine distribution. PMID:14629198

Activation of Stat-3 is involved in the induction of apoptosis after ligation of major histocompatibility complex class I molecules on human Jurkat T cells

DEFF Research Database (Denmark)

Skov, S; Nielsen, M; Bregenholt, S

1998-01-01

Activation of Janus tyrosine kinases (Jak) and Signal transducers and activators of transcription (Stat) after ligation of major histocompatibility complex class I (MHC-I) was explored in Jurkat T cells. Cross-linking of MHC-I mediated tyrosine phosphorylation of Tyk2, but not Jak1, Jak2, and Jak3......-probe derived from the interferon-gamma activated site (GAS) in the c-fos promoter, a common DNA sequence for Stat protein binding. An association between hSIE and Stat-3 after MHC-I ligation was directly demonstrated by precipitating Stat-3 from nuclear extracts with biotinylated hSIE probe and avidin......-coupled agarose. To investigate the function of the activated Stat-3, Jurkat T cells were transiently transfected with a Stat-3 isoform lacking the transactivating domain. This dominant-negative acting Stat-3 isoform significantly inhibited apoptosis induced by ligation of MHC-I. In conclusion, our data suggest...

Effect of UV irradiation on the apoptosis and necrosis of Jurkat cells using UV LEDs

Science.gov (United States)

Inada, Shunko A.; Amano, Hiroshi; Akasaki, Isamu; Morita, Akimichi; Kobayashi, Keiko

2009-02-01

Phototherapy is a very effective method for treating most of the incurable skin diseases. A fluorescent light bulb is used as a conventional UV light source for this type of therapy. However, infrared radiation from the light source sometimes causes serious problems on patient's health. In addition, the normal part of the skin is irradiated when a large fluorescent light bulb is used. Moreover, a conventional UV irradiation system is heavy and has a short lifetime and a high electrical power consumption. Therefore, a new UV light source for solving the problems of phototherapy is required. To realize low-power-consumption, lightweight and long-lifetime systems, group III nitride-based UV-A1 light-emitting diodes (LEDs) were investigated. We examined the UV LED irradiation of Jurkat cell, which is a tumor cell and more sensitive to UV light than a healthy cell. The numbers of apoptotic and necrotic cells were confirmed to be the same using a UV LED and a conventional lamp system. The UV LED showed the possibility of realizing a new UV light source for phototherapy.

Effect of vibrational stress and spaceflight on regulation of heat shock proteins hsp70 and hsp27 in human lymphocytes (Jurkat)

Science.gov (United States)

Cubano, L. A.; Lewis, M. L.

2001-01-01

Heat shock protein levels are increased in cells as a result of exposure to stress. To determine whether heat shock protein regulation could be used to evaluate stress in cells during spaceflight, the response of Jurkat cells to spaceflight and simulated space shuttle launch vibration was investigated by evaluating hsp70 and hsp27 gene expression. Gene expression was assessed by reverse transcription-polymerase chain reaction using mRNA extracted from vibrated, nonvibrated, space-flown, and ground control cells. Results indicate that mechanical stresses of vibration and low gravity do not up-regulate the mRNA for hsp70, although the gene encoding hsp27 is up-regulated by spaceflight but not by vibration. In ground controls, the mRNA for hsp70 and hsp27 increased with time in culture. We conclude that hsp70 gene expression is a useful indicator of stress related to culture density but is not an indicator of the stresses of launch vibration or microgravity. Up-regulation of hsp27 gene expression in microgravity is a new finding.

Caspase-dependant activation of chymotrypsin-like proteases mediates nuclear events during Jurkat T cell apoptosis

International Nuclear Information System (INIS)

O'Connell, A.R.; Lee, B.W.; Stenson-Cox, C.

2006-01-01

Apoptosis involves a cascade of biochemical and morphological changes resulting in the systematic disintegration of the cell. Caspases are central mediators of this process. Supporting and primary roles for serine proteases as pro-apoptotic mediators have also been highlighted. Evidence for such roles comes largely from the use of pharmacological inhibitors; as a consequence information regarding their apoptotic function and biochemical properties has been limited. Here, we circumvented limitations associated with traditional serine protease inhibitors through use of a fluorescently labelled inhibitor of serine proteases (FLISP) that allowed for analysis of the specificity, regulation and positioning of apoptotic serine proteases within a classical apoptotic cascade. We demonstrate that staurosporine triggers a caspase-dependant induction of chymotrypsin-like activity in the nucleus of apoptotic Jurkat T cells. We show that serine protease activity is required for the generation of late stage nuclear events including condensation, fragmentation and DNA degradation. Furthermore, we reveal caspase-dependant activation of two chymotrypsin-like protein species that we hypothesize mediate cell death-associated nuclear events

Plasma membrane associated membranes (PAM) from Jurkat cells contain STIM1 protein is PAM involved in the capacitative calcium entry?

Science.gov (United States)

Kozieł, Katarzyna; Lebiedzinska, Magdalena; Szabadkai, Gyorgy; Onopiuk, Marta; Brutkowski, Wojciech; Wierzbicka, Katarzyna; Wilczyński, Grzegorz; Pinton, Paolo; Duszyński, Jerzy; Zabłocki, Krzysztof; Wieckowski, Mariusz R

2009-12-01

A proper cooperation between the plasma membrane, the endoplasmic reticulum and the mitochondria seems to be essential for numerous cellular processes involved in Ca(2+) signalling and maintenance of Ca(2+) homeostasis. A presence of microsomal and mitochondrial proteins together with those characteristic for the plasma membrane in the fraction of the plasma membrane associated membranes (PAM) indicates a formation of stabile interactions between these three structures. We isolated the plasma membrane associated membranes from Jurkat cells and found its significant enrichment in the plasma membrane markers including plasma membrane Ca(2+)-ATPase, Na(+), K(+)-ATPase and CD3 as well as sarco/endoplasmic reticulum Ca(2+) ATPase as a marker of the endoplasmic reticulum membranes. In addition, two proteins involved in the store-operated Ca(2+) entry, Orai1 located in the plasma membrane and an endoplasmic reticulum protein STIM1 were found in this fraction. Furthermore, we observed a rearrangement of STIM1-containing protein complexes isolated from Jurkat cells undergoing stimulation by thapsigargin. We suggest that the inter-membrane compartment composed of the plasma membrane and the endoplasmic reticulum, and isolated as a stabile plasma membrane associated membranes fraction, might be involved in the store-operated Ca(2+) entry, and their formation and rebuilding have an important regulatory role in cellular Ca(2+) homeostasis.

Induction of CD69 expression by cagPAI-positive Helicobacter pylori infection

Institute of Scientific and Technical Information of China (English)

Naoki Mori; Chie Ishikawa; Masachika Senba

2011-01-01

AIM: To investigate and elucidate the molecular mech-anism that regulates inducible expression of CD69 by Helicobacter pylori (H. pylori ) infection.METHODS: The expression levels of CD69 in a T-cell line, Jurkat, primary human peripheral blood mononu-clear cells (PBMCs), and CD4+T cells, were assessed by immunohistochemistry, reverse transcription polymerase chain reaction, and flow cytometry. Activation of CD69 promoter was detected by reporter gene. Nuclear factor (NF)-κB activation in Jurkat cells infected with H. pylori was evaluated by electrophoretic mobility shift assay. The role of NF-κB signaling in H. pylori -induced CD69 expression was analyzed using inhibitors of NF-κB and dominant-negative mutants. The isogenic mutants with disrupted cag pathogenicity island ( cagPAI) and virD4 were used to elucidate the role of cagPAI-encoding type Ⅳ secretion system and CagA in CD69 expression.RESULTS: CD69 staining was detected in mucosal lymphocytes and macrophages in specimens of pa-tients with H. pylori -positive gastritis. Although cagPAI-positive H. pylori and an isogenic mutant of virD4 induced CD69 expression, an isogenic mutant of cag-PAI failed to induce this in Jurkat cells. H. pylori also induced CD69 expression in PBMCs and CD4+T cells. The activation of the CD69 promoter by H. pylori was mediated through NF-κB. Transfection of dominant-negative mutants of IκBs, IκB kinases, and NF-κB-inducing kinase inhibited H. pylori -induced CD69 activation. Inhibitors of NF-κB suppressed H. pylori -induced CD69 mRNA expression.CONCLUSION: The results suggest that H. pylori in-duces CD69 expression through the activation of NF-κB. cagPAI might be relevant in the induction of CD69 expression in T cells. CD69 in T cells may play a role in H. pylori -induced gastritis.

Quantitative Secretome Analysis of Activated Jurkat Cells Using Click Chemistry-Based Enrichment of Secreted Glycoproteins.

Science.gov (United States)

Witzke, Kathrin E; Rosowski, Kristin; Müller, Christian; Ahrens, Maike; Eisenacher, Martin; Megger, Dominik A; Knobloch, Jürgen; Koch, Andrea; Bracht, Thilo; Sitek, Barbara

2017-01-06

Quantitative secretome analyses are a high-performance tool for the discovery of physiological and pathophysiological changes in cellular processes. However, serum supplements in cell culture media limit secretome analyses, but serum depletion often leads to cell starvation and consequently biased results. To overcome these limiting factors, we investigated a model of T cell activation (Jurkat cells) and performed an approach for the selective enrichment of secreted proteins from conditioned medium utilizing metabolic marking of newly synthesized glycoproteins. Marked glycoproteins were labeled via bioorthogonal click chemistry and isolated by affinity purification. We assessed two labeling compounds conjugated with either biotin or desthiobiotin and the respective secretome fractions. 356 proteins were quantified using the biotin probe and 463 using desthiobiotin. 59 proteins were found differentially abundant (adjusted p-value ≤0.05, absolute fold change ≥1.5) between inactive and activated T cells using the biotin method and 86 using the desthiobiotin approach, with 31 mutual proteins cross-verified by independent experiments. Moreover, we analyzed the cellular proteome of the same model to demonstrate the benefit of secretome analyses and provide comprehensive data sets of both. 336 proteins (61.3%) were quantified exclusively in the secretome. Data are available via ProteomeXchange with identifier PXD004280.

Dual acylation and lipid raft association of Src-family protein tyrosine kinases are required for SDF-1/CXCL12-mediated chemotaxis in the Jurkat human T cell lymphoma cell line.

Science.gov (United States)

Zaman, Sabiha N; Resek, Mary E; Robbins, Stephen M

2008-10-01

Chemokines play pivotal roles in regulating a wide variety of biological processes by modulating cell migration and recruitment. Deregulation of chemokine signaling can alter cell recruitment, contributing to the pathogenic states associated with autoimmune disease, inflammatory disorders, and sepsis. During chemotaxis, lipid rafts and their resident signaling molecules have been demonstrated to partition to different parts of the cell. Herein, we investigated the role of lipid raft resident Src-family kinases (SFK) in stromal cell-derived factor 1/CXCL12-mediated chemotaxis. We have shown that Lck-deficient J.CaM 1.6 cells are defective in CXCL12-mediated chemotaxis in contrast to their parental counterpart, Jurkat cells. Ectopic expression of the SFK hematopoietic cell kinase (Hck) in J.CaM 1.6 cells reconstituted CXCL12 responsiveness. The requirement of lipid raft association of SFK was assessed using both isoforms of Hck: the dually acylated p59(Hck) isoform that is targeted to lipid rafts and the monoacylated p61(Hck) isoform that is nonraft-associated. We have shown using several gain and loss of acylation alleles that dual acylation of Hck was required for CXCL12-mediated chemotaxis in J.CaM 1.6 cells. These results highlight the importance of the unique microenvironment provided by lipid rafts and their specific contribution in providing specificity to CXCL12 signaling.

Evaluation of the Genetic Response of U937 and Jurkat Cells to 10-Nanosecond Electrical Pulses (nsEP.

Directory of Open Access Journals (Sweden)

Caleb C Roth

Full Text Available Nanosecond electrical pulse (nsEP exposure activates signaling pathways, produces oxidative stress, stimulates hormone secretion, causes cell swelling and induces apoptotic and necrotic death. The underlying biophysical connection(s between these diverse cellular reactions and nsEP has yet to be elucidated. Using global genetic analysis, we evaluated how two commonly studied cell types, U937 and Jurkat, respond to nsEP exposure. We hypothesized that by studying the genetic response of the cells following exposure, we would gain direct insight into the stresses experienced by the cell and in turn better understand the biophysical interaction taking place during the exposure. Using Ingenuity Systems software, we found genes associated with cell growth, movement and development to be significantly up-regulated in both cell types 4 h post exposure to nsEP. In agreement with our hypothesis, we also found that both cell lines exhibit significant biological changes consistent with mechanical stress induction. These results advance nsEP research by providing strong evidence that the interaction of nsEPs with cells involves mechanical stress.

A chimeric antigen receptor for TRAIL-receptor 1 induces apoptosis in various types of tumor cells.

Science.gov (United States)

Kobayashi, Eiji; Kishi, Hiroyuki; Ozawa, Tatsuhiko; Hamana, Hiroshi; Nakagawa, Hidetoshi; Jin, Aishun; Lin, Zhezhu; Muraguchi, Atsushi

2014-10-31

Tumor necrosis factor (TNF)-related apoptosis-inducing ligand (TRAIL) and its associated receptors (TRAIL-R/TR) are attractive targets for cancer therapy because TRAIL induces apoptosis in tumor cells through TR while having little cytotoxicity on normal cells. Therefore, many agonistic monoclonal antibodies (mAbs) specific for TR have been produced, and these induce apoptosis in multiple tumor cell types. However, some TR-expressing tumor cells are resistant to TR-specific mAb-induced apoptosis. In this study, we constructed a chimeric antigen receptor (CAR) of a TRAIL-receptor 1 (TR1)-specific single chain variable fragment (scFv) antibody (TR1-scFv-CAR) and expressed it on a Jurkat T cell line, the KHYG-1 NK cell line, and human peripheral blood lymphocytes (PBLs). We found that the TR1-scFv-CAR-expressing Jurkat cells killed target cells via TR1-mediated apoptosis, whereas TR1-scFv-CAR-expressing KHYG-1 cells and PBLs killed target cells not only via TR1-mediated apoptosis but also via CAR signal-induced cytolysis, resulting in cytotoxicity on a broader range if target cells than with TR1-scFv-CAR-expressing Jurkat cells. The results suggest that TR1-scFv-CAR could be a new candidate for cancer gene therapy. Copyright © 2014 Elsevier Inc. All rights reserved.

Effects of alpha fetoprotein on escape of Bel 7402 cells from attack of lymphocytes

International Nuclear Information System (INIS)

Li, Mengsen; Liu, Xinhua; Zhou, Sheng; Li, Pingfeng; Li, Gang

2005-01-01

Involvement of AFP against apoptosis of tumor cell has been implicated in its evasion of immune surveillance. However, the molecular events of immune escape mechanisms are still unknown. The major observations reported here relate to a possible mechanism by which heptoloma Bel 7402 cells escape immune surveillance in vitro. Western blotting and a well-characterized cofocal scanning image were performed to analyze the expression of Fas/FasL and caspase-3 in co-cultured Bel 7402 and Jurkat cells. After co-culture with Jurkat cells, up-regulated Fas and reduced FasL expression could be observed. Treatment with AFP could remarkably inhibit the elevated Fas and, whereas, induce the FasL expression in co-cultured Bel 7402 cells. Cells co-culture could induce the expression of caspase-3 in both cells line. The elevated caspase-3 in Bel 7402 cells was abolished following the treatment of AFP. The expression of caspase-3 was elevated in co-cultured Jurkat cells treated with AFP. No detectable change on the expression of survivin was examined in both cells line. Monoclonal antibody against AFP treatment alone did not obviously influence the growth of cells, as well as the expression of Fas/FasL and caspase-3. However, the effect of AFP could be blocked by antibody. our results provide evidence that AFP could promote the escape of liver cancer cells from immune surveillance through blocking the caspase signal pathway of tumor cells and triggering the Fas/FasL interaction between tumor cells and lymphocytes

Co-Introduced Functional CCR2 Potentiates In Vivo Anti-Lung Cancer Functionality Mediated by T Cells Double Gene-Modified to Express WT1-Specific T-Cell Receptor

Science.gov (United States)

Asai, Hiroaki; Fujiwara, Hiroshi; An, Jun; Ochi, Toshiki; Miyazaki, Yukihiro; Nagai, Kozo; Okamoto, Sachiko; Mineno, Junichi; Kuzushima, Kiyotaka; Shiku, Hiroshi; Inoue, Hirofumi; Yasukawa, Masaki

2013-01-01

Background and Purpose Although gene-modification of T cells to express tumor-related antigen-specific T-cell receptor (TCR) or chimeric antigen receptor (CAR) has clinically proved promise, there still remains room to improve the clinical efficacy of re-directed T-cell based antitumor adoptive therapy. In order to achieve more objective clinical responses using ex vivo-expanded tumor-responsive T cells, the infused T cells need to show adequate localized infiltration into the tumor. Methodology/Principal Findings Human lung cancer cells variously express a tumor antigen, Wilms' Tumor gene product 1 (WT1), and an inflammatory chemokine, CCL2. However, CCR2, the relevant receptor for CCL2, is rarely expressed on activated T-lymphocytes. A HLA-A2402+ human lung cancer cell line, LK79, which expresses high amounts of both CCL2 and WT1 mRNA, was employed as a target. Normal CD8+ T cells were retrovirally gene-modified to express both CCR2 and HLA-A*2402-restricted and WT1235–243 nonapeptide-specific TCR as an effector. Anti-tumor functionality mediated by these effector cells against LK79 cells was assessed both in vitro and in vivo. Finally the impact of CCL2 on WT1 epitope-responsive TCR signaling mediated by the effector cells was studied. Introduced CCR2 was functionally validated using gene-modified Jurkat cells and human CD3+ T cells both in vitro and in vivo. Double gene-modified CD3+ T cells successfully demonstrated both CCL2-tropic tumor trafficking and cytocidal reactivity against LK79 cells in vitro and in vivo. CCL2 augmented the WT1 epitope-responsive TCR signaling shown by relevant luciferase production in double gene-modified Jurkat/MA cells to express luciferase and WT1-specific TCR, and CCL2 also dose-dependently augmented WT1 epitope-responsive IFN-γ production and CD107a expression mediated by these double gene-modifiedCD3+ T cells. Conclusion/Significance Introduction of the CCL2/CCR2 axis successfully potentiated in vivo anti-lung cancer

Co-introduced functional CCR2 potentiates in vivo anti-lung cancer functionality mediated by T cells double gene-modified to express WT1-specific T-cell receptor.

Directory of Open Access Journals (Sweden)

Hiroaki Asai

Full Text Available BACKGROUND AND PURPOSE: Although gene-modification of T cells to express tumor-related antigen-specific T-cell receptor (TCR or chimeric antigen receptor (CAR has clinically proved promise, there still remains room to improve the clinical efficacy of re-directed T-cell based antitumor adoptive therapy. In order to achieve more objective clinical responses using ex vivo-expanded tumor-responsive T cells, the infused T cells need to show adequate localized infiltration into the tumor. METHODOLOGY/PRINCIPAL FINDINGS: Human lung cancer cells variously express a tumor antigen, Wilms' Tumor gene product 1 (WT1, and an inflammatory chemokine, CCL2. However, CCR2, the relevant receptor for CCL2, is rarely expressed on activated T-lymphocytes. A HLA-A2402(+ human lung cancer cell line, LK79, which expresses high amounts of both CCL2 and WT1 mRNA, was employed as a target. Normal CD8(+ T cells were retrovirally gene-modified to express both CCR2 and HLA-A*2402-restricted and WT1(235-243 nonapeptide-specific TCR as an effector. Anti-tumor functionality mediated by these effector cells against LK79 cells was assessed both in vitro and in vivo. Finally the impact of CCL2 on WT1 epitope-responsive TCR signaling mediated by the effector cells was studied. Introduced CCR2 was functionally validated using gene-modified Jurkat cells and human CD3(+ T cells both in vitro and in vivo. Double gene-modified CD3(+ T cells successfully demonstrated both CCL2-tropic tumor trafficking and cytocidal reactivity against LK79 cells in vitro and in vivo. CCL2 augmented the WT1 epitope-responsive TCR signaling shown by relevant luciferase production in double gene-modified Jurkat/MA cells to express luciferase and WT1-specific TCR, and CCL2 also dose-dependently augmented WT1 epitope-responsive IFN-γ production and CD107a expression mediated by these double gene-modified CD3(+ T cells. CONCLUSION/SIGNIFICANCE: Introduction of the CCL2/CCR2 axis successfully potentiated in

Failure to synthesize the human T-cell CD3-zeta chain and its consequence for the T-cell receptor-CD3 complex expression

DEFF Research Database (Denmark)

Geisler, C; Kuhlmann, J; Plesner, T

1989-01-01

components, the human T-cell tumour line Jurkat was chemically mutagenized followed by negative selection with F101.01 (a monoclonal antibody against the TcR-CD3 complex), and cloning. Growing clones were analysed for TcR-CD3 expression by immunofluorescence. One clone, J79, was found to express greatly...... diminished levels of TcR-CD3. This clone produced all the TcR-CD3 components except the CD3-zeta, as demonstrated by metabolic labelling and immunoprecipitation followed by one- and two-dimensional sodium dodecyl sulphate-polyacrylamide gel electrophoresis. These data indicate that the CD3-zeta determines...

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

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

2011-07-29

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

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

International Nuclear Information System (INIS)

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

2011-01-01

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

Combined metabonomic and quantitative real-time PCR analyses reveal systems metabolic changes in Jurkat T-cells treated with HIV-1 Tat protein.

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Liao, Wenting; Tan, Guangguo; Zhu, Zhenyu; Chen, Qiuli; Lou, Ziyang; Dong, Xin; Zhang, Wei; Pan, Wei; Chai, Yifeng

2012-11-02

HIV-1 Tat protein is released by infected cells and can affect bystander uninfected T cells and induce numerous biological responses which contribute to its pathogenesis. To elucidate the complex pathogenic mechanism, we conducted a comprehensive investigation on Tat protein-related extracellular and intracellular metabolic changes in Jurkat T-cells using combined gas chromatography-mass spectrometry (GC-MS), reversed-phase liquid chromatography-mass spectrometry (RPLC-MS) and a hydrophilic interaction liquid chromatography-mass spectrometry (HILIC-MS)-based metabonomics approach. Quantitative real-time PCR (qRT-PCR) analyses were further employed to measure expressions of several relevant enzymes together with perturbed metabolic pathways. Combined metabonomic and qRT-PCR analyses revealed that HIV-1 Tat caused significant and comprehensive metabolic changes, as represented by significant changes of 37 metabolites and 10 relevant enzymes in HIV-1 Tat-treated cells. Using MetaboAnalyst 2.0, it was found that 11 pathways (Impact-value >0.10) among the regulated pathways were acutely perturbed, including sphingolipid metabolism, glycine, serine and threonine metabolism, pyruvate metabolism, inositol phosphate metabolism, arginine and proline metabolism, citrate cycle, phenylalanine metabolism, tryptophan metabolism, pentose phosphate pathway, glycerophospholipid metabolism, glycolysis or gluconeogenesis. These results provide metabolic evidence of the complex pathogenic mechanism of HIV-1 Tat protein as a "viral toxin", and would help obligate Tat protein as "an important target" for therapeutic intervention and vaccine development.

Impacts of autophagy-inducing ingredient of areca nut on tumor cells.

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Ching-Yu Yen

Full Text Available Areca nut (AN is a popular carcinogen used by about 0.6-1.2 billion people worldwide. Although AN contains apoptosis-inducing ingredients, we previously demonstrated that both AN extract (ANE and its 30-100 kDa fraction (ANE 30-100K predominantly induce autophagic cell death in both normal and malignant cells. In this study, we further explored the action mechanism of ANE 30-100K-induced autophagy (AIA in Jurkat T lymphocytes and carcinoma cell lines including OECM-1 (mouth, CE81T/VGH (esophagus, SCC25 (tongue, and SCC-15 (tongue. The results showed that chemical- and small hairpin RNA (shRNA-mediated inhibition of AMP-activated protein kinase (AMPK resulted in the attenuation of AIA in Jurkat T but not in OECM-1 cells. Knockdown of Atg5 and Beclin 1 expressions ameliorated AIA in OECM-1/CE81T/VGH/Jurkat T and OECM-1/SCC25/SCC-15, respectively. Furthermore, ANE 30-100K could activate caspase-3 after inhibition of Beclin 1 expression in OECM-1/SCC25/SCC15 cells. Meanwhile, AMPK was demonstrated to be the upstream activator of the extracellular-regulated kinase (ERK in Jurkat T cells, and inhibition of MEK attenuated AIA in Jurkat T/OECM-1/CE81T/VGH cells. Finally, we also found that multiple myeloma RPMI8226, lymphoma U937, and SCC15 cells survived from long-term non-cytotoxic ANE 30-100K treatment exhibited stronger resistance against serum deprivation through upregulated autophagy. Collectively, our studies indicate that Beclin-1 and Atg5 but not AMPK are commonly required for AIA, and MEK/ERK pathway is involved in AIA. Meanwhile, it is also suggested that long-term AN usage might increase the resistance of survived tumor cells against serum-limited conditions.

Ethanol extracts of black pepper or turmeric down-regulated SIRT1 protein expression in Daudi culture cells.

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Nishimura, Yuri; Kitagishi, Yasuko; Yoshida, Hitomi; Okumura, Naoko; Matsuda, Satoru

2011-01-01

SIRT1 is a mammalian candidate molecule involved in longevity and diverse metabolic processes. The present study aimed to determine the effects of certain herbs and spices on SIRT1 expression. Human cell lines Daudi, Jurkat, U937 and K562 were cultured in RPMI-1640. Herb and spice powders were prepared and the supernatants were collected. RT-PCR was used to quantify the expression level of the gene. Protein samples were then analyzed by Western blotting. Western blotting revealed the down-regulation of SIRT1 protein expression in Daudi cells treated with extracts of black pepper or turmeric. On the other hand, the effect on the SIRT1 gene expression examined by reverse transcription polymerase chain reaction was unaltered. In conclusion, component(s) of certain herbs and spices may induce the down-regulation of SIRT1 protein.

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

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Huang Y

2018-02-01

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

Retinoic acid morpholine amide (RAMA) inhibits expression of Fas ligand through EP1 receptor in colon cancer cells.

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Chen, Shao-Xuan; Du, Shi-Yu; Wang, Yun-Ting; Zhao, Hong-Chuan; Zhang, Yan-Li; Yao, Li

2016-01-01

Among the members of tumour necrosis factor family Fas ligand on binding to its receptor strongly induces apoptosis of tumour-infiltrating lymphocytes (TIL). Thus, FasL acts as an inhibitor of anti-tumour immune response. The present study demonstrates that retinoic acid morpholine amide (RAMA) significantly suppresses FasL expression in colon cancer cells in a dose- and time-dependent manner. The suppression of FasL mRNA and proteins was significant at a concentration of 30 μM after 48 h in CLT85 and HT26 colon cancer cells. There was around 2.6- and 3.2-fold decrease in FasL mRNA after incubation with 30 μM of RAMA in CLT85 cells and HT26 cells, respectively. The results from Western blot showed a decrease in FasL mRNA and protein expression in both CLT85 and HT26 cells after suppression of cyclooxygenase (COX)-2 and COX-1 by RNAi. However, when COX-2-specific silencer RNA (siCOX-2)- and siCOX-1-treated CLT85 and HT26 cells were exposed to RAMA, inhibition of FasL expression was further suppressed. The siCOX-2-treated CLT85 and HT26 cells on exposure to RAMA showed ∼87 and ∼54 % reduction in FasL mRNA, respectively. Co-culture of Jurkat T cells with RAMA-treated HT26 and CLT85 cells decreased the viability of Jurkat T cells by only 2 and 4.3 %, respectively, compared to 19.5 and 37.3 % in control HT26 and CLT85 cells. The results from real-time reverse transcription polymerase chain reaction (RT-PCR) and immunoblotting showed that suppression of EP1 prevented RAMA-induced FasL suppression in CLT85 cells at both the mRNA and protein levels. Thus, RAMA can be a potent therapeutic agent for the treatment of colon tumours.

Epigonal Conditioned Media from Bonnethead Shark, Sphyrna tiburo, Induces Apoptosis in a T-Cell Leukemia Cell Line, Jurkat E6-1

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Courtney Bennett

2013-08-01

Full Text Available Representatives of Subclass Elasmobranchii are cartilaginous fish whose members include sharks, skates, and rays. Because of their unique phylogenetic position of being the most primitive group of vertebrates to possess all the components necessary for an adaptive immune system, the immune regulatory compounds they possess may represent the earliest evolutionary forms of novel compounds with the potential for innovative therapeutic applications. Conditioned medium, generated from short term culture of cells from the epigonal organ of bonnethead sharks (Sphyrna tiburo, has been shown to have potent reproducible cytotoxic activity against a variety of human tumor cell lines in vitro. Existing data suggest that epigonal conditioned medium (ECM exerts this cytotoxic activity through induction of apoptosis in target cells. This manuscript describes apoptosis induction in a representative tumor cell line, Jurkat E6-1, in response to treatment with ECM at concentrations of 1 and 2 mg/mL. Data indicate that ECM exposure initiates the mitochondrial pathway of apoptosis through activation of caspase enzymes. Future purification of ECM components may result in the isolation of an immune-regulatory compound with potential therapeutic benefit for treatment of human cancer.

The HIV-1 Tat protein modulates CD4 expression in human T cells through the induction of miR-222.

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Orecchini, Elisa; Doria, Margherita; Michienzi, Alessandro; Giuliani, Erica; Vassena, Lia; Ciafrè, Silvia Anna; Farace, Maria Giulia; Galardi, Silvia

2014-01-01

Several cellular microRNAs show substantial changes in expression during HIV-1 infection and their active role in the viral life cycle is progressively emerging. In the present study, we found that HIV-1 infection of Jurkat T cells significantly induces the expression of miR-222. We show that this induction depends on HIV-1 Tat protein, which is able to increase the transcriptional activity of NFkB on miR-222 promoter. Moreover, we demonstrate that miR-222 directly targets CD4, a key receptor for HIV-1, thus reducing its expression. We propose that Tat, by inducing miR-222 expression, complements the CD4 downregulation activity exerted by other viral proteins (i.e., Nef, Vpu, and Env), and we suggest that this represents a novel mechanism through which HIV-1 efficiently represses CD4 expression in infected cells.

Prostaglandin E2 stimulates Fas ligand expression via the EP1 receptor in colon cancer cells.

LENUS (Irish Health Repository)

O'Callaghan, G

2012-02-03

Fas ligand (FasL\\/CD95L) is a member of the tumour necrosis factor superfamily that triggers apoptosis following crosslinking of the Fas receptor. Despite studies strongly implicating tumour-expressed FasL as a major inhibitor of the anti-tumour immune response, little is known about the mechanisms that regulate FasL expression in tumours. In this study, we show that the cyclooxygenase (COX) signalling pathway, and in particular prostaglandin E(2) (PGE(2)), plays a role in the upregulation of FasL expression in colon cancer. Suppression of either COX-2 or COX-1 by RNA interference in HCA-7 and HT29 colon tumour cells reduced FasL expression at both the mRNA and protein level. Conversely, stimulation with PGE(2) increased FasL expression and these cells showed increased cytotoxicity against Fas-sensitive Jurkat T cells. Prostaglandin E(2)-induced FasL expression was mediated by signalling via the EP1 receptor. Moreover, immunohistochemical analysis using serial sections of human colon adenocarcinomas revealed a strong positive correlation between COX-2 and FasL (r=0.722; P<0.0001) expression, and between EP1 receptor and FasL (r=0.740; P<0.0001) expression, in the tumour cells. Thus, these findings indicate that PGE(2) positively regulates FasL expression in colon tumour cells, adding another pro-neoplastic activity to PGE(2).

Axl acts as a tumor suppressor by regulating LIGHT expression in T lymphoma

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Young, Kon-Ji; Park, A-Reum; Choi, Ha-Rim; Lee, Hwa-Youn; Kim, Su-Man; Chung, Byung Yeoup; Park, Chul-Hong; Choi, Hyo Jin; Ko, Young-Hyeh; Bai, Hyoung-Woo; Kang, Hyung-Sik

2017-01-01

Axl is an oncogenic receptor tyrosine kinase that plays a role in many cancers. LIGHT (Lymphotoxin-related inducible ligand that competes for glycoprotein D binding to herpesvirus entry mediator on T cells) is a ligand that induces robust anti-tumor immunity by enhancing the recruitment and activation of effector immune cells at tumor sites. We observed that mouse EL4 and human Jurkat T lymphoma cells that stably overexpressed Axl also showed high expression of LIGHT. When Jurkat-Axl cells were treated with Gas6, a ligand for Axl, LIGHT expression was upregulated through activation of the PI3K/AKT signaling pathway and transcriptional induction by Sp1. The lytic activity of cytotoxic T lymphocytes and natural killer cells was enhanced by EL4-Axl cells. In addition, tumor volume and growth were markedly reduced due to enhanced apoptotic cell death in EL4-Axl tumor-bearing mice as compared to control mice. We also observed upregulated expression of CCL5 and its receptor, CCR5, and enhanced intratumoral infiltration of cytotoxic T lymphocytes and natural killer cells in EL4-Axl-bearing mice as compared to mock controls. These data strongly suggested that Axl exerts novel tumor suppressor effects by inducing upregulation of LIGHT in the tumor microenvironment of T lymphoma. PMID:28423548

Elusive Role of the CD94/NKG2C NK Cell Receptor in the Response to Cytomegalovirus: Novel Experimental Observations in a Reporter Cell System

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Aldi Pupuleku

2017-10-01

Full Text Available Human cytomegalovirus (HCMV infection promotes the differentiation and persistent expansion of a mature NK cell subset, which displays high surface levels of the activating CD94/NKG2C NK cell receptor, together with additional distinctive phenotypic and functional features. The mechanisms underlying the development of adaptive NK cells remain uncertain but some observations support the involvement of a cognate interaction of CD94/NKG2C with ligand(s displayed by HCMV-infected cells. To approach this issue, the heterodimer and its adaptor (DAP12 were expressed in the human Jurkat leukemia T cell line; signaling was detected by transfection of a reporter plasmid encoding for Luciferase (Luc under NFAT/AP1-dependent control. Engagement of the receptor by solid-phase bound CD94- or NKG2C-specific monoclonal antibodies (mAbs triggered Luc expression. Moreover, reporter activation was detectable upon interaction with HLA-E+ 721.221 (.221-AEH cells, as well as with 721.221 cells incubated with synthetic peptides, which stabilized surface expression of endogenous HLA-E; the response was specifically antagonized by soluble NKG2C- and HLA-E-specific mAbs. By contrast, activation of Jurkat-NKG2C+ was undetectable upon interaction with Human Fetal Foreskin Fibroblasts (HFFF infected with HCMV laboratory strains (i.e., AD169, Towne, regardless of their differential ability to preserve surface HLA-E expression. On the other hand, infection with two clinical isolates or with the endotheliotropic TB40/E strain triggered Jurkat-NKG2C+ activation; yet, this response was not inhibited by blocking mAbs and was independent of CD94/NKG2C expression. The results are discussed in the framework of previous observations supporting the hypothetical existence of specific ligand(s for CD94/NKG2C in HCMV-infected cells.

[Effect of PKA Gene on Acute Lymphoblastic Leukemia in Children and Its Mechanism].

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Wang, Chao-Jie; Wang, Li-Juan; Zhao, Ding

2018-02-01

To explore the effect of PKA gene on acute T lymphocyte leukemia cells in children and its mechanism. Jurkat and Sup-T1 cells were divided into 2 group: control group (Jurkat and Sup-T1 cells treated with non-specific siRNA) and transfected group (Jurkat and Sup-T1 cells transfected with PKA siRNA). The effects of down-regulating the expression of PKA gene on the viability, proliferotion, migration and cell cycle distribution of Jurkat and Sup-T1 cells in 2 groups were analyzed by CCK-8 assay, transwell experiment, cell colony-formation test and flow cytometry; the cyclin-related protein levels after transfection with PKA siRNA were detected by Western blot. It was revealed that the expression of PKA in Jurkat and Sup-T1 cells decreased to different degree after siRNA transfection(PPKA gene expression can decrease the proliferation and migration of tumor cells, and also can restrict the cell proliferation through related cell cycle proteins.

Dynamic gene expression response to altered gravity in human T cells.

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Thiel, Cora S; Hauschild, Swantje; Huge, Andreas; Tauber, Svantje; Lauber, Beatrice A; Polzer, Jennifer; Paulsen, Katrin; Lier, Hartwin; Engelmann, Frank; Schmitz, Burkhard; Schütte, Andreas; Layer, Liliana E; Ullrich, Oliver

2017-07-12

We investigated the dynamics of immediate and initial gene expression response to different gravitational environments in human Jurkat T lymphocytic cells and compared expression profiles to identify potential gravity-regulated genes and adaptation processes. We used the Affymetrix GeneChip® Human Transcriptome Array 2.0 containing 44,699 protein coding genes and 22,829 non-protein coding genes and performed the experiments during a parabolic flight and a suborbital ballistic rocket mission to cross-validate gravity-regulated gene expression through independent research platforms and different sets of control experiments to exclude other factors than alteration of gravity. We found that gene expression in human T cells rapidly responded to altered gravity in the time frame of 20 s and 5 min. The initial response to microgravity involved mostly regulatory RNAs. We identified three gravity-regulated genes which could be cross-validated in both completely independent experiment missions: ATP6V1A/D, a vacuolar H + -ATPase (V-ATPase) responsible for acidification during bone resorption, IGHD3-3/IGHD3-10, diversity genes of the immunoglobulin heavy-chain locus participating in V(D)J recombination, and LINC00837, a long intergenic non-protein coding RNA. Due to the extensive and rapid alteration of gene expression associated with regulatory RNAs, we conclude that human cells are equipped with a robust and efficient adaptation potential when challenged with altered gravitational environments.

The HIV-1 Tat protein modulates CD4 expression in human T cells through the induction of miR-222

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Orecchini, Elisa; Doria, Margherita; Michienzi, Alessandro; Giuliani, Erica; Vassena, Lia; Ciafrè, Silvia Anna; Farace, Maria Giulia; Galardi, Silvia

2014-01-01

Several cellular microRNAs show substantial changes in expression during HIV-1 infection and their active role in the viral life cycle is progressively emerging. In the present study, we found that HIV-1 infection of Jurkat T cells significantly induces the expression of miR-222. We show that this induction depends on HIV-1 Tat protein, which is able to increase the transcriptional activity of NFkB on miR-222 promoter. Moreover, we demonstrate that miR-222 directly targets CD4, a key receptor for HIV-1, thus reducing its expression. We propose that Tat, by inducing miR-222 expression, complements the CD4 downregulation activity exerted by other viral proteins (i.e., Nef, Vpu, and Env), and we suggest that this represents a novel mechanism through which HIV-1 efficiently represses CD4 expression in infected cells. PMID:24717285

Human T-lymphotropic virus type I tax regulates the expression of the human lymphotoxin gene.

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Tschachler, E; Böhnlein, E; Felzmann, S; Reitz, M S

1993-01-01

Human T-lymphotropic virus type-I (HTLV-I)-infected T-cell lines constitutively produce high levels of lymphotoxin (LT). To analyze the mechanisms that lead to the expression of LT in HTLV-I-infected cell lines, we studied regulatory regions of the human LT promoter involved in the activation of the human LT gene. As determined by deletional analysis, sequences between +137 and -116 (relative to the transcription initiation site) are sufficient to direct expression of a reporter gene in the HTLV-I-infected cell line MT-2. Site-directed mutation of a of the single kappa B-like motif present in the LT promoter region (positions -99 to -89) completely abrogated LT promoter activity in MT-2 cells, suggesting that this site plays a critical role in the activation of the human LT gene. Transfection of LT constructs into HTLV-I-uninfected and -unstimulated Jurkat and U937 cell lines showed little to no activity of the LT promoter. Cotransfection of the same constructs with a tax expression plasmid into Jurkat cells led to detectable promoter activity, which could be significantly increased by stimulation of the cells with phorbol myristate acetate (PMA). Similarly, cotransfection of the LT promoter constructs and the tax expression plasmid into U937 cells led to significant promoter activity upon stimulation with PMA. These data suggest that HTLV-I tax is involved in the upregulation of LT gene expression in HTLV-I-infected cells.

Human T lymphotropic virus type-1 p30II alters cellular gene expression to selectively enhance signaling pathways that activate T lymphocytes

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Feuer Gerold

2004-11-01

Full Text Available Abstract Background Human T-lymphotropic virus type-1 (HTLV-1 is a deltaretrovirus that causes adult T-cell leukemia/lymphoma and is implicated in a variety of lymphocyte-mediated disorders. HTLV-1 contains both regulatory and accessory genes in four pX open reading frames. pX ORF-II encodes two proteins, p13II and p30II, which are incompletely defined in the virus life cycle or HTLV-1 pathogenesis. Proviral clones of the virus with pX ORF-II mutations diminish the ability of the virus to maintain viral loads in vivo. Exogenous expression of p30II differentially modulates CREB and Tax-responsive element-mediated transcription through its interaction with CREB-binding protein/p300 and represses tax/rex RNA nuclear export. Results Herein, we further characterized the role of p30II in regulation of cellular gene expression, using stable p30II expression system employing lentiviral vectors to test cellular gene expression with Affymetrix U133A arrays, representing ~33,000 human genes. Reporter assays in Jurkat T cells and RT-PCR in Jurkat and primary CD4+ T-lymphocytes were used to confirm selected gene expression patterns. Our data reveals alterations of interrelated pathways of cell proliferation, T-cell signaling, apoptosis and cell cycle in p30II expressing Jurkat T cells. In all categories, p30II appeared to be an overall repressor of cellular gene expression, while selectively increasing the expression of certain key regulatory genes. Conclusions We are the first to demonstrate that p30II, while repressing the expression of many genes, selectively activates key gene pathways involved in T-cell signaling/activation. Collectively, our data suggests that this complex retrovirus, associated with lymphoproliferative diseases, relies upon accessory gene products to modify cellular environment to promote clonal expansion of the virus genome and thus maintain proviral loads in vivo.

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

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Zi-Xun Yan

2015-01-01

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

The hydroxyflavone, fisetin, suppresses mast cell activation induced by interaction with activated T cell membranes

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Nagai, K; Takahashi, Y; Mikami, I; Fukusima, T; Oike, H; Kobori, M

2009-01-01

Background and purpose: Cell-to-cell interactions between mast cells and activated T cells are increasingly recognized as a possible mechanism in the aetiology of allergic or non-allergic inflammatory disorders. To determine the anti-allergic effect of fisetin, we examined the ability of fisetin to suppress activation of the human mast cell line, HMC-1, induced by activated Jurkat T cell membranes. Experimental approach: HMC-1 cells were incubated with or without fisetin for 15 min and then co-cultured with Jurkat T cell membranes activated by phorbol-12-myristate 13-acetate for 16 h. We determined gene expression in activated HMC-1 cells by DNA microarray and quantitative reverse transcription (RT)-PCR analysis. We also examined activation of the transcription factor NF-κB and MAP kinases (MAPKs) in activated HMC-1 cells. Key results: Fisetin suppresses cell spreading and gene expression in HMC-1 cells stimulated by activated T cell membranes. Additionally, we show that these stimulated HMC-1 cells expressed granzyme B. The stimulatory interaction also induced activation of NF-κB and MAPKs; these activations were suppressed by fisetin. Fisetin also reduced the amount of cell surface antigen CD40 and intercellular adhesion molecule-1 (ICAM-1) on activated HMC-1 cells. Conclusions and implications: Fisetin suppressed activation of HMC-1 cells by activated T cell membranes by interfering with cell-to-cell interaction and inhibiting the activity of NF-κB and MAPKs and thereby suppressing gene expression. Fisetin may protect against the progression of inflammatory diseases by limiting interactions between mast cells and activated T cells. PMID:19702784

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

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Maalouf, Katia; Baydoun, Elias; Rizk, Sandra

2011-01-01

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

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

International Nuclear Information System (INIS)

Maalouf, Katia; Baydoun, Elias; Rizk, Sandra

2011-01-01

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

27-Hydroxycholesterol and 7alpha-hydroxycholesterol trigger a sequence of events leading to migration of CCR5-expressing Th1 lymphocytes

Energy Technology Data Exchange (ETDEWEB)

Kim, Sun-Mi, E-mail: lala1647@hanmail.net [Department of Pharmacology, Pusan National University, School of Medicine, Yangsan, Gyeongnam 626-870 (Korea, Republic of); Kim, Bo-Young, E-mail: kimboyoung@pusan.ac.kr [Department of Pharmacology, Pusan National University, School of Medicine, Yangsan, Gyeongnam 626-870 (Korea, Republic of); Lee, Sae-A, E-mail: saeah486@nate.com [Department of Pharmacology, Pusan National University, School of Medicine, Yangsan, Gyeongnam 626-870 (Korea, Republic of); Eo, Seong-Kug, E-mail: vetvirus@chonbuk.ac.kr [Laboratory of Microbiology, College of Veterinary Medicine and Bio-Safety Research Institute, Chonbuk National University, Jeonju, Jeonbuk 561-756 (Korea, Republic of); Yun, Yungdae, E-mail: yunyung@ewha.ac.kr [Department of Life Science, Ewha Womans University, Seoul 120-750 (Korea, Republic of); Kim, Chi-Dae, E-mail: chidkim@pusan.ac.kr [Department of Pharmacology, Pusan National University, School of Medicine, Yangsan, Gyeongnam 626-870 (Korea, Republic of); Kim, Koanhoi, E-mail: koanhoi@pusan.ac.kr [Department of Pharmacology, Pusan National University, School of Medicine, Yangsan, Gyeongnam 626-870 (Korea, Republic of)

2014-02-01

Th1 lymphocytes are predominant in atherosclerotic lesions. However, mechanisms involved in the Th1 predominance are unknown. We have investigated the possibility of Th1 lymphocyte recruitment in a cholesterol-rich milieu. A high cholesterol diet resulted in enhanced expression of CCR5 ligands, including CCL3 and CCL4, but not of proatherogenic CXCR3 ligands, in atherosclerotic arteries of ApoE{sup −/−} mice. 27-Hydroxycholesterol and 7α-hydroxycholesterol, cholesterol oxides (oxysterols) detected in abundance in atherosclerotic lesions, greatly induced the transcription of CCL3 and CCL4 genes in addition to enhancing secretion of corresponding proteins by THP-1 monocytic cells. However, an identical or even higher concentration of cholesterol, 7β-hydroxycholesterol, and 7-ketocholsterol did not influence expression of these chemokines. Conditioned media containing the CCR5 ligands secreted from THP-1 cells induced migration of Jurkat T cells expressing CCR5, a characteristic chemokine receptor of Th1 cells, but not of Jurkat T cells that do not express CCR5. The migration of CCR5-expressing Jurkat T cells was abrogated in the presence of a CCR5-neutralizing antibody. 27-Hydroxycholesterol and 7α-hydroxycholesterol enhanced phosphorylation of Akt. Pharmacological inhibitors of phosphoinositide-3-kinase/Akt pathways blocked transcription as well as secretion of CCL3 and CCL4 in conjunction with attenuated migration of CCR5-expressing Jurkat T cells. This is the first report on the involvement of cholesterol oxides in migration of distinct subtype of T cells. We propose that 27-hydroxycholesterol and 7α-hydroxycholesterol can trigger a sequence of events that leads to recruitment of Th1 lymphocytes and phosphoinositide-3-kinase/Akt pathways play a major role in the process. - Graphical abstract: Th1 lymphocytes are predominant in atherosclerotic lesions. However, mechanisms involved in the Th1 predominance are unknown. We have investigated the possibility of

27-Hydroxycholesterol and 7alpha-hydroxycholesterol trigger a sequence of events leading to migration of CCR5-expressing Th1 lymphocytes

International Nuclear Information System (INIS)

Kim, Sun-Mi; Kim, Bo-Young; Lee, Sae-A; Eo, Seong-Kug; Yun, Yungdae; Kim, Chi-Dae; Kim, Koanhoi

2014-01-01

Th1 lymphocytes are predominant in atherosclerotic lesions. However, mechanisms involved in the Th1 predominance are unknown. We have investigated the possibility of Th1 lymphocyte recruitment in a cholesterol-rich milieu. A high cholesterol diet resulted in enhanced expression of CCR5 ligands, including CCL3 and CCL4, but not of proatherogenic CXCR3 ligands, in atherosclerotic arteries of ApoE −/− mice. 27-Hydroxycholesterol and 7α-hydroxycholesterol, cholesterol oxides (oxysterols) detected in abundance in atherosclerotic lesions, greatly induced the transcription of CCL3 and CCL4 genes in addition to enhancing secretion of corresponding proteins by THP-1 monocytic cells. However, an identical or even higher concentration of cholesterol, 7β-hydroxycholesterol, and 7-ketocholsterol did not influence expression of these chemokines. Conditioned media containing the CCR5 ligands secreted from THP-1 cells induced migration of Jurkat T cells expressing CCR5, a characteristic chemokine receptor of Th1 cells, but not of Jurkat T cells that do not express CCR5. The migration of CCR5-expressing Jurkat T cells was abrogated in the presence of a CCR5-neutralizing antibody. 27-Hydroxycholesterol and 7α-hydroxycholesterol enhanced phosphorylation of Akt. Pharmacological inhibitors of phosphoinositide-3-kinase/Akt pathways blocked transcription as well as secretion of CCL3 and CCL4 in conjunction with attenuated migration of CCR5-expressing Jurkat T cells. This is the first report on the involvement of cholesterol oxides in migration of distinct subtype of T cells. We propose that 27-hydroxycholesterol and 7α-hydroxycholesterol can trigger a sequence of events that leads to recruitment of Th1 lymphocytes and phosphoinositide-3-kinase/Akt pathways play a major role in the process. - Graphical abstract: Th1 lymphocytes are predominant in atherosclerotic lesions. However, mechanisms involved in the Th1 predominance are unknown. We have investigated the possibility of Th1

Nitric oxide and bcl-2 mediated the apoptosis induced by nickel(II) in human T hybridoma cells

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Guan Fuqin; Zhang Dongmei; Wang Xinchang; Chen Junhui

2007-01-01

Although effects of nickel(II) on the immune system have long been recognized, little is known about the effects of nickel(II) on the induction of apoptosis and related signaling events in T cells. In the present study, we investigated the roles and signaling pathways of nickel(II) in the induction of apoptosis in a human T cell line jurkat. The results showed that the cytotoxic effects of Ni involved significant morphological changes and chromosomal condensation (Hoechst 33258 staining). Analyses of hypodiploid cells and FITC-Annexin V and PI double staining showed significant increase of apoptosis in jurkat cells 6, 12 and 24 h after nickel(II) treatment. Flow cytometry analysis also revealed that the loss of mitochondrial membrane potential (MMP) occurred concomitantly with the onset of NiCl 2 -induced apoptosis. Induction of apoptotic cell death by nickel was mediated by reduction of bcl-2 expression. Furthermore, nickel stimulated the generation of nitric oxide (NO). These results suggest that nickel(II) chloride induces jurkat cells apoptosis via nitric oxide generation, mitochondrial depolarization and bcl-2 suppression

5-Lipoxygenase contributes to PPARγ activation in macrophages in response to apoptotic cells.

Science.gov (United States)

von Knethen, Andreas; Sha, Lisa K; Kuchler, Laura; Heeg, Annika K; Fuhrmann, Dominik; Heide, Heinrich; Wittig, Ilka; Maier, Thorsten J; Steinhilber, Dieter; Brüne, Bernhard

2013-12-01

Macrophage polarization to an anti-inflammatory phenotype upon contact with apoptotic cells is a contributing hallmark to immune suppression during the late phase of sepsis. Although the peroxisome proliferator-activated receptor γ (PPARγ) supports this macrophage phenotype switch, it remains elusive how apoptotic cells activate PPARγ. Assuming that a molecule causing PPARγ activation in macrophages originates in the cell membrane of apoptotic cells we analyzed lipid rafts from apoptotic, necrotic, and living human Jurkat T cells which showed the presence of 5-lipoxygenase (5-LO) in lipid rafts of apoptotic cells only. Incubating macrophages with lipid rafts of apoptotic, but not necrotic or living cells, induced PPAR responsive element (PPRE)-driven mRuby reporter gene expression in RAW 264.7 macrophages stably transduced with a 4xPPRE containing vector. Experiments with lipid rafts of apoptotic murine EL4 T cells revealed similar results. To verify the involvement of 5-LO in activating PPARγ in macrophages, Jurkat T cells were incubated with the 5-LO inhibitor MK-866 prior to induction of apoptosis, which failed to induce mRuby expression. Similar results were obtained with lipid rafts of apoptotic EL4 T cells preexposed to the 5-LO inhibitors zileuton and CJ-13610. Interestingly, Jurkat T cells overexpressing 5-LO failed to activate PPARγ in macrophages, while their 5-LO overexpressing apoptotic counterparts did. Our results suggest that during apoptosis 5-LO gets associated with lipid rafts and synthesizes ligands that in turn stimulate PPARγ in macrophages. © 2013.

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

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Katia Maalouf

2011-02-01

Full Text Available Katia Maalouf1, Elias Baydoun2, Sandra Rizk11Department of Natural Sciences, Lebanese American University, Beirut, Lebanon; 2Department of Biology, American University of Beirut, Beirut, LebanonBackground: Adult lymphoblastic leukemia (ALL is a malignancy that occurs in white blood cells. The overall cure rate in children is 85%, whereas it is only 40% in adults. Kefir is an important probiotic that contains many bioactive ingredients, which give it unique health benefits. It has been shown to control several cellular types of cancer.Purpose: The present study investigates the effect of a cell-free fraction of kefir on CEM and Jurkat cells, which are human T-lymphotropic virus type I (HTLV-1-negative malignant T-lymphocytes.Methods: Cells were incubated with different kefir concentrations. The cytotoxicity of the compound was evaluated by determining the percentage viability of cells. The effect of all the noncytotoxic concentrations of kefir on the proliferation of CEM and Jurkat cells was then assessed. The levels of transforming growth factor-alpha (TGF-α, transforming growth factor- beta1 (TGF-β1, matrix metalloproteinase-2 (MMP-2, and MMP-9 mRNA upon kefir treatment were then analyzed using reverse transcriptase polymerase chain reaction (RT-PCR. Finally, the growth inhibitory effects of kefir on cell-cycle progression/apoptosis were assessed by Cell Death Detection (ELISA and flow cytometry.Results: The maximum cytotoxicity recorded after 48-hours treatment with 80 µg/µL kefir was only 42% and 39% in CEM and Jurkat cells, respectively. The percent reduction in proliferation was very significant, and was dose-, and time-dependent. In both cell lines, kefir exhibited its antiproliferative effect by downregulating TGF-α and upregulating TGF- β1 mRNA expression. Upon kefir treatment, a marked increase in cell-cycle distribution was noted in the preG1 phase of CEM and Jurkat cells, indicating the proapoptotic effect of kefir, which was

miR-17-92 expression in differentiated T cells - implications for cancer immunotherapy

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Martinson Jeremy

2010-02-01

Full Text Available Abstract Background Type-1 T cells are critical for effective anti-tumor immune responses. The recently discovered microRNAs (miRs are a large family of small regulatory RNAs that control diverse aspects of cell function, including immune regulation. We identified miRs differentially regulated between type-1 and type-2 T cells, and determined how the expression of such miRs is regulated. Methods We performed miR microarray analyses on in vitro differentiated murine T helper type-1 (Th1 and T helper type-2 (Th2 cells to identify differentially expressed miRs. We used quantitative RT-PCR to confirm the differential expression levels. We also used WST-1, ELISA, and flow cytometry to evaluate the survival, function and phenotype of cells, respectively. We employed mice transgenic for the identified miRs to determine the biological impact of miR-17-92 expression in T cells. Results Our initial miR microarray analyses revealed that the miR-17-92 cluster is one of the most significantly over-expressed miR in murine Th1 cells when compared with Th2 cells. RT-PCR confirmed that the miR-17-92 cluster expression was consistently higher in Th1 cells than Th2 cells. Disruption of the IL-4 signaling through either IL-4 neutralizing antibody or knockout of signal transducer and activator of transcription (STAT6 reversed the miR-17-92 cluster suppression in Th2 cells. Furthermore, T cells from tumor bearing mice and glioma patients had decreased levels of miR-17-92 when compared with cells from non-tumor bearing counterparts. CD4+ T cells derived from miR-17-92 transgenic mice demonstrated superior type-1 phenotype with increased IFN-γ production and very late antigen (VLA-4 expression when compared with counterparts derived from wild type mice. Human Jurkat T cells ectopically expressing increased levels of miR-17-92 cluster members demonstrated increased IL-2 production and resistance to activation-induced cell death (AICD. Conclusion The type-2-skewing

Vesicle-associated membrane protein 7 (VAMP-7) is essential for target cell killing in a natural killer cell line

International Nuclear Information System (INIS)

Marcet-Palacios, Marcelo; Odemuyiwa, Solomon O.; Coughlin, Jason J.; Garofoli, Daniella; Ewen, Catherine; Davidson, Courtney E.; Ghaffari, Mazyar; Kane, Kevin P.; Lacy, Paige; Logan, Michael R.; Befus, A. Dean; Bleackley, R. Chris; Moqbel, Redwan

2008-01-01

Natural killer cells recognize and induce apoptosis in foreign, transformed or virus-infected cells through the release of perforin and granzymes from secretory lysosomes. Clinically, NK-cell mediated killing is a major limitation to successful allo- and xenotransplantation. The molecular mechanisms that regulate the fusion of granzyme B-containing secretory lysosomes to the plasma membrane in activated NK cells, prior to target cell killing, are not fully understood. Using the NK cell line YT-Indy as a model, we have investigated the expression of SNAP REceptors (SNAREs), both target (t-) and vesicular (v-) SNAREs, and their function in granzyme B-mediated target cell killing. Our data showed that YT-Indy cells express VAMP-7 and SNAP-23, but not VAMP-2. VAMP-7 was associated with granzyme B-containing lysosomal granules. Using VAMP-7 small interfering RNA (siRNA), we successfully knocked down the expression of VAMP-7 protein in YT-Indy to less than 10% of untreated cells in 24 h. VAMP7-deficient YT-Indy cells activated via co-culture with Jurkat cells released <1 ng/mL of granzyme B, compared to 1.5-2.5 μg/mL from controls. Using Jurkat cells as targets, we showed a 7-fold reduction in NK cell-mediated killing by VAMP-7 deficient YT-Indy cells. Our results show that VAMP-7 is a crucial component of granzyme B release and target cell killing in the NK cell line YT-Indy. Thus, targeting VAMP-7 expression specifically with siRNA, following transplantation, may be a viable strategy for preventing NK cell-mediated transplant rejection, in vivo

Imbalance of morphofunctional responses of Jurkat T lymphoblasts at short-term culturing with relief zinc- or copper-containing calcium phosphate coating on titanium.

Science.gov (United States)

Litvinova, L S; Shupletsova, V V; Dunets, N A; Khaziakhmatova, O G; Yurova, K A; Khlusova, M Yu; Slepchenko, G B; Cherempey, E G; Sharkeev, Yu P; Komarova, E G; Sedelnikova, M B; Khlusov, I A

2017-01-01

Morphofunctional response of Jurkat T cells that were cultured for 24 h on substrates prepared from commercially pure titanium with relief microarc bilateral calcium phosphate coating containing copper or zinc was studied. Changes in the concentration of essential trace elements contained in this coating can cause significant imbalance of molecular processes of differentiation, secretion, apoptosis, and necrosis and reduce tumor cell survival.

Failure to synthesize the CD3-gamma chain. Consequences for T cell antigen receptor assembly, processing, and expression

DEFF Research Database (Denmark)

Geisler, C

1992-01-01

surface expression of the Ti/CD3 complex. Transfection of the wild-type CD3-gamma gene into JGN reconstituted expression of functional Ti/CD3 complexes, and analysis of T cell lines producing different amounts of CD3-gamma indicated that CD3-gamma and CD3-delta competed for the binding to CD3-epsilon.......The TCR consists of the Ti alpha beta heterodimer and the associated CD3 chains, CD3 gamma delta epsilon zeta 2 or zeta eta. The structural relationships between the subunits of the Ti/CD3 complex are still not fully understood. To explore the roles of the individual CD3 chains for the assembly......, intracellular processing, and expression of the TCR, mutants of the T cell line Jurkat were isolated. One variant, JGN, was found to produce all the Ti/CD3 components with the exception of CD3-gamma. The results indicate that: 1) the tetrameric form (Ti alpha beta-CD3 delta epsilon) of the Ti/CD3 complex...

CD4+ Primary T Cells Expressing HCV-Core Protein Upregulate Foxp3 and IL-10, Suppressing CD4 and CD8 T Cells

Science.gov (United States)

Aguado, Enrique; Garcia-Cozar, Francisco

2014-01-01

Adaptive T cell responses are critical for controlling HCV infection. While there is clinical evidence of a relevant role for regulatory T cells in chronic HCV-infected patients, based on their increased number and function; mechanisms underlying such a phenomena are still poorly understood. Accumulating evidence suggests that proteins from Hepatitis C virus can suppress host immune responses. We and others have shown that HCV is present in CD4+ lymphocytes from chronically infected patients and that HCV-core protein induces a state of unresponsiveness in the CD4+ tumor cell line Jurkat. Here we show that CD4+ primary T cells lentivirally transduced with HCV-core, not only acquire an anergic phenotype but also inhibit IL-2 production and proliferation of bystander CD4+ or CD8+ T cells in response to anti-CD3 plus anti-CD28 stimulation. Core-transduced CD4+ T cells show a phenotype characterized by an increased basal secretion of the regulatory cytokine IL-10, a decreased IFN-γ production upon stimulation, as well as expression of regulatory T cell markers, CTLA-4, and Foxp3. A significant induction of CD4+CD25+CD127lowPD-1highTIM-3high regulatory T cells with an exhausted phenotype was also observed. Moreover, CCR7 expression decreased in HCV-core expressing CD4+ T cells explaining their sequestration in inflamed tissues such as the infected liver. This work provides a new perspective on de novo generation of regulatory CD4+ T cells in the periphery, induced by the expression of a single viral protein. PMID:24465502

CD4+ primary T cells expressing HCV-core protein upregulate Foxp3 and IL-10, suppressing CD4 and CD8 T cells.

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Cecilia Fernandez-Ponce

Full Text Available Adaptive T cell responses are critical for controlling HCV infection. While there is clinical evidence of a relevant role for regulatory T cells in chronic HCV-infected patients, based on their increased number and function; mechanisms underlying such a phenomena are still poorly understood. Accumulating evidence suggests that proteins from Hepatitis C virus can suppress host immune responses. We and others have shown that HCV is present in CD4+ lymphocytes from chronically infected patients and that HCV-core protein induces a state of unresponsiveness in the CD4+ tumor cell line Jurkat. Here we show that CD4+ primary T cells lentivirally transduced with HCV-core, not only acquire an anergic phenotype but also inhibit IL-2 production and proliferation of bystander CD4+ or CD8+ T cells in response to anti-CD3 plus anti-CD28 stimulation. Core-transduced CD4+ T cells show a phenotype characterized by an increased basal secretion of the regulatory cytokine IL-10, a decreased IFN-γ production upon stimulation, as well as expression of regulatory T cell markers, CTLA-4, and Foxp3. A significant induction of CD4+CD25+CD127(lowPD-1(highTIM-3(high regulatory T cells with an exhausted phenotype was also observed. Moreover, CCR7 expression decreased in HCV-core expressing CD4+ T cells explaining their sequestration in inflamed tissues such as the infected liver. This work provides a new perspective on de novo generation of regulatory CD4+ T cells in the periphery, induced by the expression of a single viral protein.

Fas ligand expression in human and mouse cancer cell lines; a caveat on over-reliance on mRNA data

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Ryan Aideen E

2006-02-01

Full Text Available Abstract Background During carcinogenesis, tumors develop multiple mechanisms for evading the immune response, including upregulation of Fas ligand (FasL/CD95L expression. Expression of FasL may help to maintain tumor cells in a state of immune privilege by inducing apoptosis of anti-tumor immune effector cells. Recently this idea has been challenged by studies reporting that tumor cells of varying origin do not express FasL. In the present study, we aimed to comprehensively characterize FasL expression in tumors of both murine and human origin over a 72 hour time period. Methods RNA and protein was extracted from six human (SW620, HT29, SW480, KM12SM, HCT116, Jurkat and three mouse (CMT93, CT26, B16F10 cancer cell lines at regular time intervals over a 72 hour time period. FasL expression was detected at the mRNA level by RT-PCR, using intron spanning primers, and at the protein level by Western Blotting and immunofluorescence, using a polyclonal FasL- specific antibody. Results Expression of FasL mRNA and protein was observed in all cell lines analysed. However, expression of FasL mRNA varied dramatically over time, with cells negative for FasL mRNA at many time points. In contrast, 8 of the 9 cell lines constitutively expressed FasL protein. Thus, cells can abundantly express FasL protein at times when FasL mRNA is absent. Conclusion These findings demonstrate the importance of complete analysis of FasL expression by tumor cells in order to fully characterize its biological function and may help to resolve the discrepancies present in the literature regarding FasL expression and tumor immune privilege.

p53 functional impairment and high p21waf1/cip1 expression in human T-cell lymphotropic/leukemia virus type I-transformed T cells.

Science.gov (United States)

Cereseto, A; Diella, F; Mulloy, J C; Cara, A; Michieli, P; Grassmann, R; Franchini, G; Klotman, M E

1996-09-01

Human T-cell lymphotropic/leukemia virus type I (HTLV-I) is associated with T-cell transformation both in vivo and in vitro. Although some of the mechanisms responsible for transformation remain unknown, increasing evidence supports a direct role of viral as well as dysregulated cellular proteins in transformation. We investigated the potential role of the tumor suppressor gene p53 and of the p53-regulated gene, p21waf1/cip1 (wild-type p53 activated fragment 1/cycling dependent kinases [cdks] interacting protein 1), in HTLV-I-infected T cells. We have found that the majority of HTLV-I-infected T cells have the wild-type p53 gene. However, its function in HTLV-I-transformed cells appears to be impaired, as shown by the lack of appropriate p53-mediated responses to ionizing radiation (IR). Interestingly, the expression of the p53 inducible gene, p21waf1/cip1, is elevated at the messenger ribonucleic acid and protein levels in all HTLV-I-infected T-cell lines examined as well as in Taxl-1, a human T-cell line stably expressing Tax. Additionally, Tax induces upregulation of a p21waf1/cip1 promoter-driven luciferase gene in p53 null cells, and increases p21waf1/cip1 expression in Jurkat T cells. These findings suggest that the Tax protein is at least partially responsible for the p53-independent expression of p21waf1/cip1 in HTLV-I-infected cells. Dysregulation of p53 and p21waf1/cip1 proteins regulating cell-cycle progression, may represent an important step in HTLV-I-induced T-cell transformation.

13-methyltetradecanoic acid exhibits anti-tumor activity on T-cell lymphomas in vitro and in vivo by down-regulating p-AKT and activating caspase-3.

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Qingqing Cai

Full Text Available 13-Methyltetradecanoic acid (13-MTD, a saturated branched-chain fatty acid purified from soy fermentation products, induces apoptosis in human cancer cells. We investigated the inhibitory effects and mechanism of action of 13-MTD on T-cell non-Hodgkin's lymphoma (T-NHL cell lines both in vitro and in vivo. Growth inhibition in response to 13-MTD was evaluated by the cell counting kit-8 (CCK-8 assay in three T-NHL cell lines (Jurkat, Hut78, EL4 cells. Flow cytometry analyses were used to monitor the cell cycle and apoptosis. Proteins involved in 13-MTD-induced apoptosis were examined in Jurkat cells by western blotting. We found that 13-MTD inhibited proliferation and induced the apoptosis of T-NHL cell lines. 13-MTD treatment also induced a concentration-dependent arrest of Jurkat cells in the G1-phase. During 13-MTD-induced apoptosis in Jurkat cells, the cleavage of caspase-3 and poly ADP-ribose polymerase (PARP, a caspase enzymolysis product were detected after incubation for 2 h, and increased after extending the incubation time. However, there was no change in the expression of Bcl-2 or c-myc proteins. The appearance of apoptotic Jurkat cells was accompanied by the inhibition of AKT and nuclear factor-kappa B (NF-κB phosphorylation. In addition, 13-MTD could also effectively inhibit the growth of T-NHL tumors in vivo in a xenograft model. The tumor inhibition rate in the experimental group was 40%. These data indicate that 13-MTD inhibits proliferation and induces apoptosis through the down-regulation of AKT phosphorylation followed by caspase activation, which may provide a new approach for treating T-cell lymphomas.

Quantitative comparison of HTLV-1 and HIV-1 cell-to-cell infection with new replication dependent vectors.

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Dmitriy Mazurov

2010-02-01

Full Text Available We have developed an efficient method to quantify cell-to-cell infection with single-cycle, replication dependent reporter vectors. This system was used to examine the mechanisms of infection with HTLV-1 and HIV-1 vectors in lymphocyte cell lines. Effector cells transfected with reporter vector, packaging vector, and Env expression plasmid produced virus-like particles that transduced reporter gene activity into cocultured target cells with zero background. Reporter gene expression was detected exclusively in target cells and required an Env-expression plasmid and a viral packaging vector, which provided essential structural and enzymatic proteins for virus replication. Cell-cell fusion did not contribute to infection, as reporter protein was rarely detected in syncytia. Coculture of transfected Jurkat T cells and target Raji/CD4 B cells enhanced HIV-1 infection two fold and HTLV-1 infection ten thousand fold in comparison with cell-free infection of Raji/CD4 cells. Agents that interfere with actin and tubulin polymerization strongly inhibited HTLV-1 and modestly decreased HIV-1 cell-to-cell infection, an indication that cytoskeletal remodeling was more important for HTLV-1 transmission. Time course studies showed that HTLV-1 transmission occurred very rapidly after cell mixing, whereas slower kinetics of HIV-1 coculture infection implies a different mechanism of infectious transmission. HTLV-1 Tax was demonstrated to play an important role in altering cell-cell interactions that enhance virus infection and replication. Interestingly, superantigen-induced synapses between Jurkat cells and Raji/CD4 cells did not enhance infection for either HTLV-1 or HIV-1. In general, the dependence on cell-to-cell infection was determined by the virus, the effector and target cell types, and by the nature of the cell-cell interaction.

Regulation of Id2 expression in EL4 T lymphoma cells overexpressing growth hormone.

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Weigent, Douglas A

2009-01-01

In previous studies, we have shown that overexpression of growth hormone (GH) in cells of the immune system upregulates proteins involved in cell growth and protects from apoptosis. Here, we report that overexpression of GH in EL4 T lymphoma cells (GHo) also significantly increased levels of the inhibitor of differentiation-2 (Id2). The increase in Id2 was suggested in both Id2 promoter luciferase assays and by Western analysis for Id2 protein. To identify the regulatory elements that mediate transcriptional activation by GH in the Id2 promoter, promoter deletion analysis was performed. Deletion analysis revealed that transactivation involved a 301-132bp region upstream to the Id2 transcriptional start site. The pattern in the human GHo Jurkat T lymphoma cell line paralleled that found in the mouse GHo EL4 T lymphoma cell line. Significantly less Id2 was detected in the nucleus of GHo EL4 T lymphoma cells compared to vector alone controls. Although serum increased the levels of Id2 in control vector alone cells, no difference was found in the total levels of Id2 in GHo EL4 T lymphoma cells treated with or without serum. The increase in Id2 expression in GHo EL4 T lymphoma cells measured by Id2 promoter luciferase expression and Western blot analysis was blocked by the overexpression of a dominant-negative mutant of STAT5. The results suggest that in EL4 T lymphoma cells overexpressing GH, there is an upregulation of Id2 protein that appears to involve STAT protein activity.

FLI1 Expression in Breast Cancer Cell Lines and Primary Breast Carcinomas is Correlated with ER, PR and HER2

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Inam Jasim Lafta

2017-12-01

Full Text Available FLI1 is a member of ETS family of transcription factors that regulate a variety of normal biologic activities including cell proliferation, differentiation, and apoptosis. The expression of FLI1 and its correlation with well-known breast cancer prognostic markers (ER, PR and HER2 was determined in primary breast tumors as well as four breast cancer lines including: MCF-7, T47D, MDA-MB-231 and MDA-MB-468 using RT-qPCR with either 18S rRNA or ACTB (β-actin for normalization of data. FLI1 mRNA level was decreased in the breast cancer cell lines under study compared to the normal breast tissue; however, Jurkat cells, which were used as a positive control, showed overexpression compared to the normal breast. Regarding primary breast carcinomas, FLI1 is significantly under expressed in all of the stages of breast cancer upon using 18S as an internal control. This FLI1 expression was correlated with ER, PR and HER2 status. In conclusion FLI1 can be exploited as a preliminary marker that can predict the status of ER, PR and HER2 in primary breast tumors.

Histone H1 interphase phosphorylation becomes largely established in G1 or early S phase and differs in G1 between T-lymphoblastoid cells and normal T cells

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Gréen Anna

2011-08-01

Full Text Available Abstract Background Histone H1 is an important constituent of chromatin, and is involved in regulation of its structure. During the cell cycle, chromatin becomes locally decondensed in S phase, highly condensed during metaphase, and again decondensed before re-entry into G1. This has been connected to increasing phosphorylation of H1 histones through the cell cycle. However, many of these experiments have been performed using cell-synchronization techniques and cell cycle-arresting drugs. In this study, we investigated the H1 subtype composition and phosphorylation pattern in the cell cycle of normal human activated T cells and Jurkat T-lymphoblastoid cells by capillary electrophoresis after sorting of exponentially growing cells into G1, S and G2/M populations. Results We found that the relative amount of H1.5 protein increased significantly after T-cell activation. Serine phosphorylation of H1 subtypes occurred to a large extent in late G1 or early S phase in both activated T cells and Jurkat cells. Furthermore, our data confirm that the H1 molecules newly synthesized during S phase achieve a similar phosphorylation pattern to the previous ones. Jurkat cells had more extended H1.5 phosphorylation in G1 compared with T cells, a difference that can be explained by faster cell growth and/or the presence of enhanced H1 kinase activity in G1 in Jurkat cells. Conclusion Our data are consistent with a model in which a major part of interphase H1 phosphorylation takes place in G1 or early S phase. This implies that H1 serine phosphorylation may be coupled to changes in chromatin structure necessary for DNA replication. In addition, the increased H1 phosphorylation of malignant cells in G1 may be affecting the G1/S transition control and enabling facilitated S-phase entry as a result of relaxed chromatin condensation. Furthermore, increased H1.5 expression may be coupled to the proliferative capacity of growth-stimulated T cells.

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

International Nuclear Information System (INIS)

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

2012-01-01

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

Novel HIV-1 knockdown targets identified by an enriched kinases/phosphatases shRNA library using a long-term iterative screen in Jurkat T-cells.

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Sylvie Rato

2010-02-01

Full Text Available HIV-1 is a complex retrovirus that uses host machinery to promote its replication. Understanding cellular proteins involved in the multistep process of HIV-1 infection may result in the discovery of more adapted and effective therapeutic targets. Kinases and phosphatases are a druggable class of proteins critically involved in regulation of signal pathways of eukaryotic cells. Here, we focused on the discovery of kinases and phosphatases that are essential for HIV-1 replication but dispensable for cell viability. We performed an iterative screen in Jurkat T-cells with a short-hairpin-RNA (shRNA library highly enriched for human kinases and phosphatases. We identified 14 new proteins essential for HIV-1 replication that do not affect cell viability. These proteins are described to be involved in MAPK, JNK and ERK pathways, vesicular traffic and DNA repair. Moreover, we show that the proteins under study are important in an early step of HIV-1 infection before viral integration, whereas some of them affect viral transcription/translation. This study brings new insights for the complex interplay of HIV-1/host cell and opens new possibilities for antiviral strategies.

RhoA and RhoC are involved in stromal cell-derived factor-1-induced cell migration by regulating F-actin redistribution and assembly.

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Luo, Jixian; Li, Dingyun; Wei, Dan; Wang, Xiaoguang; Wang, Lan; Zeng, Xianlu

2017-12-01

Stromal cell-derived factor-1 (SDF-1) signaling is important to the maintenance and progression of T-cell acute lymphoblastic leukemia by inducing chemotaxis migration. To identify the mechanism of SDF-1 signaling in the migration of T-ALL, Jurkat acute lymphoblastic leukemia cells were used. Results showed that SDF-1 induces Jurkat cell migration by F-actin redistribution and assembly, which is dependent on Rho activity. SDF-1 induced RhoA and RhoC activation, as well as reactive oxygen species (ROS) production, which was inhibited by Rho inhibitor. The Rho-dependent ROS production led to subsequent cytoskeleton redistribution and assembly in the process of migration. Additionally, RhoA and RhoC were involved in SDF-1-induced Jurkat cell migration. Taken together, we found a SDF-1/CXCR4-RhoA and RhoC-ROS-cytoskeleton pathway that regulates Jurkat cell migration in response to SDF-1. This work will contribute to a clearer insight into the migration mechanism of acute lymphoblastic leukemia.

Arsenic exposure triggers a shift in microRNA expression.

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Sturchio, Elena; Colombo, Teresa; Boccia, Priscilla; Carucci, Nicoletta; Meconi, Claudia; Minoia, Claudio; Macino, Giuseppe

2014-02-15

Exposure to inorganic Arsenic (iAs) through drinking water is a major public health problem affecting most countries. iAs has been classified by the International Agency for Research on Cancer as Group 1: "Carcinogenic to humans". Although numerous studies have shown the related adverse effects of iAs, sensitive appropriate biomarkers for studies of environmental epidemiology are still required. The present work aims at investigate the role of microRNAs (miRNAs), powerful negative regulators of gene expression, playing a key role in many physiological and pathological cellular processes, in iAs exposure. To this end, we analyzed miRNA changes in expression profile triggered by iAs exposure in Jurkat cell line. We used microarray technology to profile the expression of miRNAs following 2 μmol/L sodium arsenite treatment at different time points. Moreover, we performed phenotypic analysis of iAs treated cells. Real Time Polymerase Chain Reaction (RT-PCR) was used to validate miRNA microarray data and to assay expression modulation of selected relevant mRNAs. Finally, bioinformatics techniques were applied to reconstruct iAs-relevant molecular pathways and miRNA regulatory networks from the expression data. We report miRNAs modulated after iAs treatment in Jurkat cells. In particular, we highlight 36 miRNAs exhibiting consistent dysregulation and particularly a panel of 8 miRNAs which we also validated by RT-PCR analysis. Computational analysis of lists of putative target genes for these 8 miRNAs points to an involvement in arsenic-response pathways, for a subset of them, that were analyzed by RT-PCR. Furthermore, iAs exposure reveals induction of cell cycle progression and the failure of apoptosis, supporting the idea of iAs carcinogenic activity. Our study provides a list of miRNAs whose expression levels are affected by iAs treatment, corroborating the importance of proceeding with the hunt for specific subset of miRNAs, which can serve as potential biomarkers of

Involvement of the N-terminal part of cyclophilin B in the interaction with specific Jurkat T-cell binding sites.

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Mariller, C; Haendler, B; Allain, F; Denys, A; Spik, G

1996-07-15

Cyclophilin B (CyPB) is secreted in biological fluids such as blood or milk and binds to a specific receptor present on the human lymphoblastic cell line Jurkat and on human peripheral blood lymphocytes. This study was intended to specify the areas of CyPB that are involved in the interaction with the receptor. A synthetic peptide corresponding to the first 24 N-terminal amino acid residues of CyPB was shown to specifically recognize the receptor. Moreover, modification of Arg18 of CyPB by p-hydroxyphenlglyoxal led to a dramatic loss of affinity for the receptor. However, when this residue was replaced by an alanine residue using site-directed mutagenesis, no modification of the binding properties was found, suggesting that Arg18 is not directly involved but is sufficiently close to the interaction site to interfere with the binding when modified. Competitive binding experiments using a chimaeric protein made up of the 24 N-terminal amino acid residues of CyPB fused to the cyclophilin A core sequence confirmed the involvement of this region of CyPB in receptor binding.

Synthesis of a Tyr-Tyr Dipeptide Library and Evaluation Against Tumor Cells.

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Vasconcelos, Stanley Ns; Sciani, Juliana M; Lisboa, Nicole Mambeli; Stefani, Helio A

2018-03-09

Structural component of proteins and peptides, amino acids have been used as building blocks in the synthesis of more complex molecules with antitumor activity against several types of cancer. The search for new anticancer compounds is ongoing, especially for cancers that are very aggressive and have poor prognoses, such as leukemia. Here, we report a method to synthesize Tyr-Tyr dipeptides via sonochemistry reactions followed by functionalization of these Tyr-Tyr dipeptides with Suzuki-Miyaura and Sonogashira cross-coupling reactions in good yields. Twelve different Tyr-Tyr dipeptides were investigated against three cell lines: HaCaT; Jurkat-E6; and A2058. Some of Tyr-Tyr dipeptides showed activity against Jurkat-E6 leukaemia cells at low concentration, decreasing their viability, but not against non-tumor HaCaT cells, suggesting a cytotoxicity specific to tumor cells. All dipeptides were able to decrease the viability of Jurkat cell line, however the A2058 cell line did not respond well to treatment with the peptides. Some of the modified Tyr-Tyr dipeptides presented selective activity on leukemic tumor cells. Copyright© Bentham Science Publishers; For any queries, please email at epub@benthamscience.org.

Biological responses of T cells encapsulated with polyelectrolyte-coated gold nanorods and their cellular activities in a co-culture system

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Wattanakull, Porntida; Killingsworth, Murray C.; Pissuwan, Dakrong

2017-11-01

Currently, human T cell therapy is of considerable scientific interest. In addition, cell encapsulation has become an attractive approach in biomedical applications. Here, we propose an innovative technique of single-cell encapsulation of human T cells using polyelectrolytes combined with gold nanorods. We have demonstrated encapsulation of human Jurkat T cells with poly(sodium 4-styrenesulfonate) (PSS)-coated gold nanorods (PSS-GNRs). Other forms of encapsulation, using polyelectrolytes without GNRs, were also performed. After Jurkat T cells were encapsulated with poly(allylamine hydrochloride) (PAH) and/or PSS-GNRs or PSS, most cells survived and could proliferate. Jurkat T cells encapsulated with a double layer of PSS-GNR/PAH (PSS-GNR/PAH@Jurkat) showed the highest rate of cell proliferation when compared to 24-h encapsulated cells. With the exception of IL-6, no significant induction of inflammatory cytokines (IL-2, IL-1β, and TNF-α) was observed. Interestingly, when encapsulated cells were co-cultured with THP-1 macrophages, co-cultures exhibited TNF-α production enhancement. However, the co-culture of THP-1 macrophage and PSS-GNR/PAH@Jurkat or PSS/PAH@Jurkat did not enhance TNF-α production. No significant inductions of IL-2, IL-1β, and IL-6 were detected. These data provide promising results, demonstrating the potential use of encapsulated PSS-GNR/PAH@Jurkat to provide a more inert T cell population for immunotherapy application and other biomedical applications.

Identification of apoptosis-related PLZF target genes

International Nuclear Information System (INIS)

Bernardo, Maria Victoria; Yelo, Estefania; Gimeno, Lourdes; Campillo, Jose Antonio; Parrado, Antonio

2007-01-01

The PLZF gene encodes a BTB/POZ-zinc finger-type transcription factor, involved in physiological development, proliferation, differentiation, and apoptosis. In this paper, we investigate proliferation, survival, and gene expression regulation in stable clones from the human haematopoietic K562, DG75, and Jurkat cell lines with inducible expression of PLZF. In Jurkat cells, but not in K562 and DG75 cells, PLZF induced growth suppression and apoptosis in a cell density-dependent manner. Deletion of the BTB/POZ domain of PLZF abrogated growth suppression and apoptosis. PLZF was expressed with a nuclear speckled pattern distinctively in the full-length PLZF-expressing Jurkat clones, suggesting that the nuclear speckled localization is required for PLZF-induced apoptosis. By microarray analysis, we identified that the apoptosis-inducer TP53INP1, ID1, and ID3 genes were upregulated, and the apoptosis-inhibitor TERT gene was downregulated. The identification of apoptosis-related PLZF target genes may have biological and clinical relevance in cancer typified by altered PLZF expression

Aging-dependent DNA hypermethylation and gene expression of GSTM1 involved in T cell differentiation.

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Yeh, Shu-Hui; Liu, Cheng-Ling; Chang, Ren-Chieh; Wu, Chih-Chiang; Lin, Chia-Hsueh; Yang, Kuender D

2017-07-25

This study investigated whether aging was associated with epigenetic changes of DNA hypermethylation on immune gene expression and lymphocyte differentiation. We screened CG sites of methylation in blood leukocytes from different age populations, picked up genes with age-related increase of CG methylation content more than 15%, and validated immune related genes with CG hypermethylation involved in lymphocyte differentiation in the aged population. We found that 12 genes (EXHX1、 IL-10、 TSP50、 GSTM1、SLC5A5、SPI1、F2R、LMO2、PTPN6、FGFR2、MMP9、MET) were associated with promoter or exon one DNA hypermethylation in the aged group. Two immune related genes, GSTM1 and LMO2, were chosen to validate its aging-related CG hypermethylation in different leukocytes. We are the first to validate that GSTM1_P266 and LMO2_E128 CG methylation contents in T lymphocytes but not polymorphonuclear cells (PMNs) or mononuclear cells (MNCs) were significantly increased in the aged population. The GSTM1 mRNA expression in T lymphocytes but not PMNs or MNCs was inversely associated with the GSTM1 CG hypermethylation levels in the aged population studied. Further studies showed that lower GSTM1 CG methylation content led to the higher GSTM1 mRNA expression in T cells and knockdown of GSTM1 mRNA expression decreased type 1 T helper cell (Th1) differentiation in Jurkat T cells and normal adult CD4 T cells. The GSTM1_P266 hypermethylation in the aged population associated with lower GSTM1 mRNA expression was involved in Th1 differentiation, highlighting that modulation of aging-associated GSTM1 methylation may be able to enhance T helper cell immunity in the elders.

Mitofusin 2 Promotes Apoptosis of CD4+ T Cells by Inhibiting Autophagy in Sepsis

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Lan Ying

2017-01-01

Full Text Available Apoptosis of CD4+ T cells is a primary pathophysiological mechanism of immune dysfunction in the pathogenesis of sepsis. Mitofusin 2 (Mfn2, an integral mitochondrial outer membrane protein, has been confirmed to be associated with cellular metabolism, proliferation, and apoptosis. The function of Mfn2 in CD4+ T cell apoptosis in sepsis is poorly understood. Here, we discovered increased in vivo Mfn2 expression, autophagy deficiency, and elevated cell apoptosis in murine splenic CD4+ T cells after cecal ligation and puncture (CLP. We also observed almost identical results in splenic CD4+ T cells upon lipopolysaccharide (LPS stimulation in vitro. Furthermore, overexpression of Mfn2 resulted in impaired autophagy and increased apoptosis in Jurkat cells. Pharmacological inhibition of autophagy with 3-methyladenine enhanced Mfn2 overexpression-induced cell apoptosis. In addition, overexpression of Mfn2 downregulated phorbol myristate acetate (PMA/ionomycin-, rapamycin- and starvation-induced autophagy in Jurkat T cells. Taken together, these data indicate a critical role of Mfn2 in CD4+ T cell apoptosis in sepsis and the underlying mechanism of autophagy deficiency.

T-cell activation triggers death receptor-6 expression in a NF-kappa B and NF-AT dependent manner

Czech Academy of Sciences Publication Activity Database

Klíma, Martin; Broučková, Adéla; Koc, Michal; Anděra, Ladislav

2011-01-01

Roč. 48, 12-13 (2011), s. 1439-1447 ISSN 0161-5890 R&D Projects: GA MŠk 1M0506 Institutional research plan: CEZ:AV0Z50520514 Keywords : TNFRSF21 * T cells * Jurkat Subject RIV: EB - Genetics ; Molecular Biology Impact factor: 2.897, year: 2011

The cathepsin B inhibitor z-FA-CMK induces cell death in leukemic T cells via oxidative stress.

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Liow, K Y; Chow, Sek C

2018-01-01

The cathepsin B inhibitor benzyloxycarbonyl-phenylalanine-alanine-chloromethyl ketone (z-FA-CMK) was recently found to induce apoptosis at low concentrations in Jurkat T cells, while at higher concentrations, the cells die of necrosis. In the present study, we showed that z-FA-CMK readily depletes intracellular glutathione (GSH) with a concomitant increase in reactive oxygen species (ROS) generation. The toxicity of z-FA-CMK in Jurkat T cells was completely abrogated by N-acetylcysteine (NAC), suggesting that the toxicity mediated by z-FA-CMK is due to oxidative stress. We found that L-buthionine sulfoximine (BSO) which depletes intracellular GSH through the inhibition of GSH biosynthesis in Jurkat T cells did not promote ROS increase or induce cell death. However, NAC was still able to block z-FA-CMK toxicity in Jurkat T cells in the presence of BSO, indicating that the protective effect of NAC does not involve GSH biosynthesis. This is further corroborated by the protective effect of the non-metabolically active D-cysteine on z-FA-CMK toxicity. Furthermore, in BSO-treated cells, z-FA-CMK-induced ROS increased which remains unchanged, suggesting that the depletion of GSH and increase in ROS generation mediated by z-FA-CMK may be two separate events. Collectively, our results demonstrated that z-FA-CMK toxicity is mediated by oxidative stress through the increase in ROS generation.

Inhibition of IGF1-R overcomes IGFBP7-induced chemotherapy resistance in T-ALL

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Bartram, Isabelle; Erben, Ulrike; Ortiz-Tanchez, Jutta; Blunert, Katja; Schlee, Cornelia; Neumann, Martin; Heesch, Sandra; Baldus, Claudia D.

2015-01-01

T-cell acute lymphoblastic leukemia (T-ALL) is a genetically heterogeneous disease with the need for treatment optimization. Previously, high expression of Insulin-like growth factor binding protein 7 (IGFBP7), a member of the IGF system, was identified as negative prognostic factor in adult T-ALL patients. Since aberrant IGFBP7 expression was observed in a variety of neoplasia and was relevant for prognosis in T-ALL, we investigated the functional role of IGFBP7 in Jurkat and Molt-4 cells as in vitro models for T-ALL. Jurkat and Molt-4 cells were stably transfected with an IGFBP7 over-expression vector or the empty vector as control. Proliferation of the cells was assessed by WST-1 assays and cell cycle status was measured by flow-cytometry after BrDU/7-AAD staining. The effect of IGFBP7 over-expression on sensitivity to cytostatic drugs was determined in AnnexinV/7-AAD assays. IGF1-R protein expression was measured by Western Blot and flow-cytometric analysis. IGF1-R associated gene expression profiles were generated from microarray gene expression data of 86 T-ALL patients from the Microarrays Innovations in Leukemia (MILE) multicenter study. IGFBP7-transfected Jurkat cells proliferated less, leading to a longer survival in a nutrient–limited environment. Both IGFBP7-transfected Jurkat and Molt-4 cells showed an arrest in the G0/G1 cell cycle phase. Furthermore, Jurkat IGFBP7-transfected cells were resistant to vincristine and asparaginase treatment. Surface expression and whole protein measurement of IGF1-R protein expression showed a reduced abundance of the receptor after IGFBP7 transfection in Jurkat cells. Interestingly, combination of the IGF1-R inhibitor NPV-AEW541 restored sensitivity to vincristine in IGFBP7-transfected cells. Additionally, IGF1-R associated GEP revealed an up-regulation of important drivers of T-ALL pathogenesis and regulators of chemo-resistance and apoptosis such as NOTCH1, BCL-2, PRKCI, and TP53. This study revealed a

Activation of Tax protein by c-Jun-N-terminal kinase is not dependent on the presence or absence of the early growth response-1 gene product.

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Parra, Eduardo; Gutierréz, Luís; Ferreira, Jorge

2016-02-01

The Tax protein of human T cell leukemia virus type 1 plays a major role in the pathogenesis of adult T cell leukemia (ATL), an aggressive neoplasia of CD4+ T cells. In the present study, we investigated whether the EGR-1 pathway is involved in the regulation of Tax-induced JNK expression in human Jurkat T cells transfected to express the Tax protein in the presence or absence of PMA or ionomycin. Overexpression of EGR-1 in Jurkat cells transfected to express Tax, promoted the activation of several genes, with the most potent being those that contained AP-1 (Jun/c-Fos), whereas knockdown of endogenous EGR-1 by small interfering RNA (siRNA) somewhat reduced Tax-mediated JNK-1 transcription. Additionally, luciferase-based AP-1 and NF-κB reporter gene assays demonstrated that inhibition of EGR-1 expression by an siRNA did not affect the transcriptional activity of a consensus sequence of either AP-1 or NF-κB. On the other hand, the apoptosis assay, using all-trans retinoic acid (ATRA) as an inducer of apoptosis, confirmed that siRNA against EGR-1 failed to suppress ATRA-induced apoptosis in Jurkat and Jurkat-Tax cells, as noted by the low levels of both DEVDase activity and DNA fragmentation, indicating that the induction of apoptosis by ATRA was Egr-1-independent. Finally, our data showed that activation of Tax by JNK-1 was not dependent on the EGR-1 cascade of events, suggesting that EGR-1 is important but not a determinant for the activity for Tax-induced proliferation of Jurkat cells.

Human T-lymphotropic virus type-1 p30 alters cell cycle G2 regulation of T lymphocytes to enhance cell survival

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Silverman Lee

2007-07-01

Full Text Available Abstract Background Human T-lymphotropic virus type-1 (HTLV-1 causes adult T-cell leukemia/lymphoma and is linked to a number of lymphocyte-mediated disorders. HTLV-1 contains both regulatory and accessory genes in four pX open reading frames. pX ORF-II encodes two proteins, p13 and p30, whose roles are still being defined in the virus life cycle and in HTLV-1 virus-host cell interactions. Proviral clones of HTLV-1 with pX ORF-II mutations diminish the ability of the virus to maintain viral loads in vivo. p30 expressed exogenously differentially modulates CREB and Tax-responsive element-mediated transcription through its interaction with CREB-binding protein/p300 and while acting as a repressor of many genes including Tax, in part by blocking tax/rex RNA nuclear export, selectively enhances key gene pathways involved in T-cell signaling/activation. Results Herein, we analyzed the role of p30 in cell cycle regulation. Jurkat T-cells transduced with a p30 expressing lentivirus vector accumulated in the G2-M phase of cell cycle. We then analyzed key proteins involved in G2-M checkpoint activation. p30 expression in Jurkat T-cells resulted in an increase in phosphorylation at serine 216 of nuclear cell division cycle 25C (Cdc25C, had enhanced checkpoint kinase 1 (Chk1 serine 345 phosphorylation, reduced expression of polo-like kinase 1 (PLK1, diminished phosphorylation of PLK1 at tyrosine 210 and reduced phosphorylation of Cdc25C at serine 198. Finally, primary human lymphocyte derived cell lines immortalized by a HTLV-1 proviral clone defective in p30 expression were more susceptible to camptothecin induced apoptosis. Collectively these data are consistent with a cell survival role of p30 against genotoxic insults to HTLV-1 infected lymphocytes. Conclusion Collectively, our data are the first to indicate that HTLV-1 p30 expression results in activation of the G2-M cell cycle checkpoint, events that would promote early viral spread and T-cell

Cell fate after mitotic arrest in different tumor cells is determined by the balance between slippage and apoptotic threshold

Energy Technology Data Exchange (ETDEWEB)

Galán-Malo, Patricia; Vela, Laura; Gonzalo, Oscar; Calvo-Sanjuán, Rubén; Gracia-Fleta, Lucía; Naval, Javier; Marzo, Isabel, E-mail: imarzo@unizar.es

2012-02-01

Microtubule poisons and other anti-mitotic drugs induce tumor death but the molecular events linking mitotic arrest to cell death are still not fully understood. We have analyzed cell fate after mitotic arrest produced by the microtubule-destabilizing drug vincristine in a panel of human tumor cell lines showing different response to vincristine. In Jurkat, RPMI 8226 and HeLa cells, apoptosis was triggered shortly after vincristine-induced mitotic arrest. However, A549 cells, which express a great amount of Bcl-x{sub L} and undetectable amounts of Bak, underwent mitotic slippage prior to cell death. However, when Bcl-x{sub L} gene was silenced in A549 cells, vincristine induced apoptosis during mitotic arrest. Another different behavior was found in MiaPaca2 cells, where vincristine caused death by mitotic catastrophe that switched to apoptosis when cyclin B1 degradation was prevented by proteasome inhibition. Overexpression of Bcl-x{sub L} or silencing Bax and Bak expression delayed the onset of apoptosis in Jurkat and RPMI 8226 cells, enabling mitotic slippage and endoreduplication. In HeLa cells, overexpression of Bcl-x{sub L} switched cell death from apoptosis to mitotic catastrophe. Mcl-1 offered limited protection to vincristine-induced cell death and Mcl-1 degradation was not essential for vincristine-induced death. All these results, taken together, indicate that the Bcl-x{sub L}/Bak ratio and the ability to degrade cyclin B1 determine cell fate after mitotic arrest in the different tumor cell types. Highlights: ► Vincristine induces cell death by apoptosis or mitotic catastrophe. ► Apoptosis-proficient cells die by apoptosis during mitosis upon vincristine treatment. ► p53wt apoptosis-deficient cells undergo apoptosis from a G1-like tetraploid state. ► p53mt apoptosis-deficient cells can survive and divide giving rise to 8N cells.

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

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

2016-11-01

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

The expression analysis of ICOS-L on activated T cells and immature dendritic cells as well as malignant B cells and Grave's-disease-derived thyroid tissues by two novel mAbs against human ICOS-L.

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Wang, F; Zhu, W; Liu, T; Sun, Z; Ju, S; Ju, S; Yu, G; Xie, W; Deng, Z; Lu, B; Zhang, X

2007-01-01

ICOS-L, a newly identified member of B7 superfamily, plays an important role in immune responses. In this article, we report on two novel mouse anti-human ICOS-L monoclonal antibodies (mAbs) named as 11C4 and 12B11, whose specificities were verified by methods of flow cytometry, western blotting, and epitope competition assay. The two mAbs bound to distinct ICOS-L epitopes on B cells. Interestingly, mAb 11C4 could well recognize ICOS-L molecule on activated T cells and Jurkat cell lines, which is different from commercial anti-ICOS-L mAb (clone number MIH12) and the other mAb 12B11. In addition, we found that the expression of ICOS-L molecule was only detected on the surface of immature monocyte-derived dendritic cells (Mo-DCs) and was sharply decreased after induction of mature Mo-DCs activated by tumor necrosis factor-alpha or CD40. Furthermore, we showed that 11C4 could effectively suppress the maturation of Mo-DCs in vitro as evidenced by the low expression of CD80, CD86, CD83, and human leukocyte antigen-DR, which suggested that ICOS-L may be involved in the maturation of Mo-DCs. Using immunohistochemistry staining with mAb 11C4, the expression of ICOS-L was found in B lymphoma tissues and thyroid tissues from the Grave's disease but not in thyroid adenoma and normal thyroid tissues.

The mechanism of Jurkat cells apoptosis induced by Aggregatibacter actinomycetemcomitans cytolethal distending toxin.

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Chen, Hui-Ping; Li, Lu; Chen, Xu; Yang, Mi-Fang; Ye, Yu; Wang, Xiao-Qian; Xu, Yan

2017-06-01

Cytolethal distending toxin (CDT) which is produced by Aggregatibacter actinomycetemcomitans causes apoptosis in lymphocytes. But the specific mechanism is not clear. The aim of our research was to investigate the effect and mechanism during this process. The wild-type CdtA, CdtB, CdtC (CdtA W , CdtB W , CdtC W ) and mutant CdtB (CdtB M ) were expressed and purified respectively and the purity of each subunit was examined by BandScan software. And the type I deoxyribonuclease and PI-3,4,5-triphosphate (PI-3,4,5-P3, PIP3) phosphatase activity were detected by DNA agarose gel electrophoresis and enzyme-linked immunosorbent assay respectively. The cell apoptosis rates were analyzed by flow cytometry. The morphological changes of apoptosis cells were observed by confocal laser scanning microscopy. The protein expression of Bax and Bcl-2 was examined by western blot. Differentially expressed apoptosis-related proteins were identified based on isobaric tags for relative and absolute quantitation technology. In the present study we found that: (i) recombinant wild-type CdtA, CdtB and CdtC (CdtA W , CdtB W , CdtC W ) and mutant CdtB (CdtB M ) were correctly expressed and the purity of each protein was higher than 80%, (ii) the average apoptosis rate in wild-type CDT (CDT W ) treated groups was 50.54%, which was significantly higher than the controls (4.71%) and mutant CDT (CDT M ) treated groups (5.58%) (p apoptosis were observed in CDT W treated cells, (iv) the expression of Bax protein was significantly increased in CDT W treated cells, while Bcl-2 protein expression was significantly decreased, (v) 17 apoptosis-related proteins were expressed differentially, among which 10 proteins (SMNDC1, TNFRSF10B, UBE2I, ITM2A, CASP3, P53, EIF1, TCF3, HMGN5, CASP8) were up-regulated and 7 proteins (RRM2, TPX2, KIF11, NUCKS1, TOP2A, XRCC1, PTPLAD1, RRM2) were down-regulated, (vi) one possible apoptotic pathway [Ubc9 (UBE2I)/P53/DR5 (TNFRSF10B)/Caspase-8 (CASP8)/ Caspase-3 (CASP3

Transcriptional activation of immediate-early gene ETR101 by human T-cell leukaemia virus type I Tax

DEFF Research Database (Denmark)

Chen, Li; Ma, Shiliang; Li, Bo

2003-01-01

Human T-cell leukaemia virus type I (HTLV-I) Tax regulates viral and cellular gene expression through interactions with multiple cellular transcription pathways. This study describes the finding of immediate-early gene ETR101 expression in HTLV-I-infected cells and its regulation by Tax. ETR101...... was persistently expressed in HTLV-I-infected cells but not in HTLV-I uninfected cells. Expression of ETR101 was dependent upon Tax expression in the inducible Tax-expressing cell line JPX-9 and also in Jurkat cells transiently transfected with Tax-expressing vectors. Tax transactivated the ETR101 gene promoter......-DNA complex in HTLV-I-infected cell lines. EMSA with specific antibodies confirmed that the CREB transcription factor was responsible for formation of this specific protein-DNA complex. These results suggested that Tax directly transactivated ETR101 gene expression, mainly through a CRE sequence via the CREB...

Protein C Inhibitor (PCI) Binds to Phosphatidylserine Exposing Cells with Implications in the Phagocytosis of Apoptotic Cells and Activated Platelets

Science.gov (United States)

Rieger, Daniela; Assinger, Alice; Einfinger, Katrin; Sokolikova, Barbora; Geiger, Margarethe

2014-01-01

Protein C Inhibitor (PCI) is a secreted serine protease inhibitor, belonging to the family of serpins. In addition to activated protein C PCI inactivates several other proteases of the coagulation and fibrinolytic systems, suggesting a regulatory role in hemostasis. Glycosaminoglycans and certain negatively charged phospholipids, like phosphatidylserine, bind to PCI and modulate its activity. Phosphatidylerine (PS) is exposed on the surface of apoptotic cells and known as a phagocytosis marker. We hypothesized that PCI might bind to PS exposed on apoptotic cells and thereby influence their removal by phagocytosis. Using Jurkat T-lymphocytes and U937 myeloid cells, we show here that PCI binds to apoptotic cells to a similar extent at the same sites as Annexin V, but in a different manner as compared to live cells (defined spots on ∼10–30% of cells). PCI dose dependently decreased phagocytosis of apoptotic Jurkat cells by U937 macrophages. Moreover, the phagocytosis of PS exposing, activated platelets by human blood derived monocytes declined in the presence of PCI. In U937 cells the expression of PCI as well as the surface binding of PCI increased with time of phorbol ester treatment/macrophage differentiation. The results of this study suggest a role of PCI not only for the function and/or maturation of macrophages, but also as a negative regulator of apoptotic cell and activated platelets removal. PMID:25000564

In Vitro Cytotoxic Potential of Essential Oils of Eucalyptus benthamii and Its Related Terpenes on Tumor Cell Lines

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Patrícia Mathias Döll-Boscardin

2012-01-01

Full Text Available Eucalyptus L. is traditionally used for many medicinal purposes. In particular, some Eucalyptus species have currently shown cytotoxic properties. Local Brazilian communities have used leaves of E. benthamii as a herbal remedy for various diseases, including cancer. Considering the lack of available data for supporting this cytotoxic effect, the goal of this paper was to study the in vitro cytotoxic potential of the essential oils from young and adult leaves of E. benthamii and some related terpenes (α-pinene, terpinen-4-ol, and γ-terpinene on Jurkat, J774A.1 and HeLa cells lines. Regarding the cytotoxic activity based on MTT assay, the essential oils showed improved results than α-pinene and γ-terpinene, particularly for Jurkat and HeLa cell lines. Terpinen-4-ol revealed a cytotoxic effect against Jurkat cells similar to that observed for volatile oils. The results of LDH activity indicated that cytotoxic activity of samples against Jurkat cells probably involved cell death by apoptosis. The decrease of cell DNA content was demonstrated due to inhibition of Jurkat cells proliferation by samples as a result of cytotoxicity. In general, the essential oils from young and adult leaves of E. benthamii presented cytotoxicity against the investigated tumor cell lines which confirms their antitumor potential.

In Vitro Cytotoxic Potential of Essential Oils of Eucalyptus benthamii and Its Related Terpenes on Tumor Cell Lines

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Döll-Boscardin, Patrícia Mathias; Sartoratto, Adilson; Sales Maia, Beatriz Helena Lameiro de Noronha; Padilha de Paula, Josiane; Nakashima, Tomoe; Farago, Paulo Vitor; Kanunfre, Carla Cristine

2012-01-01

Eucalyptus L. is traditionally used for many medicinal purposes. In particular, some Eucalyptus species have currently shown cytotoxic properties. Local Brazilian communities have used leaves of E. benthamii as a herbal remedy for various diseases, including cancer. Considering the lack of available data for supporting this cytotoxic effect, the goal of this paper was to study the in vitro cytotoxic potential of the essential oils from young and adult leaves of E. benthamii and some related terpenes (α-pinene, terpinen-4-ol, and γ-terpinene) on Jurkat, J774A.1 and HeLa cells lines. Regarding the cytotoxic activity based on MTT assay, the essential oils showed improved results than α-pinene and γ-terpinene, particularly for Jurkat and HeLa cell lines. Terpinen-4-ol revealed a cytotoxic effect against Jurkat cells similar to that observed for volatile oils. The results of LDH activity indicated that cytotoxic activity of samples against Jurkat cells probably involved cell death by apoptosis. The decrease of cell DNA content was demonstrated due to inhibition of Jurkat cells proliferation by samples as a result of cytotoxicity. In general, the essential oils from young and adult leaves of E. benthamii presented cytotoxicity against the investigated tumor cell lines which confirms their antitumor potential. PMID:22645627

Detailed Analysis of Apoptosis and Delayed Luminescence of Human Leukemia Jurkat T Cells after Proton Irradiation and Treatments with Oxidant Agents and Flavonoids

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Irina Baran

2012-01-01

Full Text Available Following previous work, we investigated in more detail the relationship between apoptosis and delayed luminescence (DL in human leukemia Jurkat T cells under a wide variety of treatments. We used menadione and hydrogen peroxide to induce oxidative stress and two flavonoids, quercetin, and epigallocatechin gallate, applied alone or in combination with menadione or H2O2. 62 MeV proton beams were used to irradiate cells under a uniform dose of 2 or 10 Gy, respectively. We assessed apoptosis, cell cycle distributions, and DL. Menadione, H2O2 and quercetin were potent inducers of apoptosis and DL inhibitors. Quercetin decreased clonogenic survival and the NAD(PH level in a dose-dependent manner. Proton irradiation with 2 Gy but not 10 Gy increased the apoptotic rate. However, both doses induced a substantial G2/M arrest. Quercetin reduced apoptosis and prolonged the G2/M arrest induced by radiation. DL spectroscopy indicated that proton irradiation disrupted the electron flow within Complex I of the mitochondrial respiratory chain, thus explaining the massive necrosis induced by 10 Gy of protons and also suggested an equivalent action of menadione and quercetin at the level of the Fe/S center N2, which may be mediated by their binding to a common site within Complex I, probably the rotenone-binding site.

Freezing and post-thaw apoptotic behaviour of cells in the presence of palmitoyl nanogold particles

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Thirumala, Sreedhar; Forman, Julianne M; Monroe, W Todd; Devireddy, Ram V

2007-01-01

The aim of this study was to evaluate the freezing response of HeLa and Jurkat cells in the presence of commercially available nanoparticles, NPs (Palmitoyl Nanogold[reg], Nanoprobes). The cells were incubated with NPs for either 5 min or 3 h, and a calorimeter technique was then used to generate the volumetric shrinkage response during freezing at 20 deg. C min -1 . Concomitantly, we also examined the effect of a commonly used cryoprotectant, dimethylsulfoxide, DMSO (10% v/v ratio) on the freezing response of HeLa and Jurkat cells. By fitting a model of water transport to the experimentally determined volumetric shrinkage data, the reference hydraulic conductivity, L pg (μm/min-atm) and activation energy, E Lp (kcal mol -1 ) were obtained. For HeLa cells, the values of L pg ranged from 0.08 to 0.23 μm/min-atm, while E Lp ranged from 10.9 to 37.4 kcal mol -1 . For Jurkat cells these parameter values ranged from 0.05 to 0.16 μm/min-atm and 9.5 to 35.9 kcal mol -1 . A generic optimal cooling rate equation was then used to predict the optimal rates of freezing HeLa and Jurkat cells in the presence and absence of DMSO and NPs. The post-thaw viability and apoptotic response of HeLa and Jurkat cells was further investigated by cooling cells at three rates in the presence and absence of DMSO and NPs using a commercially available controlled rate freezer. Jurkat cells treated in this manner demonstrated an increase in their adhesive properties after 18 h incubation and adhered strongly to the bottom of the culture plate. This observation prevented further analysis of Jurkat apoptotic and necrotic post-thaw responses. There was no significant effect of NPs or DMSO alone on HeLa cell viability prior to freezing. The post-thaw results from HeLa cells show that the NPs increased the measured post-freeze apoptotic response when cooled at 1 deg. C min -1 , suggesting a possible therapeutic use of NPs in cryodestructive procedures

Evaluation of Synergetic Anticancer Activity of Berberine and Curcumin on Different Models of A549, Hep-G2, MCF-7, Jurkat, and K562 Cell Lines

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Acharya Balakrishna

2015-01-01

Full Text Available Ayurvedic system of medicine is using Berberis aristata and Curcuma longa herbs to treat different diseases including cancer. The study was performed to evaluate the synergetic anticancer activity of Berberine and Curcumin by estimating the inhibition of the cell proliferation by cytotoxicity assay using MTT method on specified human cell lines (A549, Hep-G2, MCF-7, Jurkat, and K562. All the cells were harvested from the culture and seeded in the 96-well assay plates at seeding density of 2.0 × 104 cells/well and were incubated for 24 hours. Test items Berberine with Curcumin (1 : 1, Curcumin 95% pure, and Berberine 95% pure were exposed at the concentrations of 1.25, 0.001, and 0.5 mg/mL, respectively, and incubated for a period of 48 hours followed by dispensing MTT solution (5 mg/mL. The cells were incubated at 37 ± 1°C for 4 hours followed by addition of DMSO for dissolving the formazan crystals and absorbance was read at 570 nm. Separate wells were prepared for positive control, controls (only medium with cells, and blank (only medium. The results had proven the synergetic anticancer activity of Berberine with Curcumin inducing cell death greater percentage of >77% when compared to pure curcumin with <54% and pure Berberine with <45% on average on all cell line models.

A T-cell specific transcriptional enhancer element 3' of Cα in the human T-cell receptor α locus

International Nuclear Information System (INIS)

Ho, Icheng; Yang, Lihsuan; Morle, G.; Leiden, J.M.

1989-01-01

A transcriptional enhancer element has been identified 4.5 kilobases 3' of C α (constant region α chain) in the human T-cell receptor (TCR) α-chain locus. This enhancer is active on both a TCR V α (variable region α chain) promoter and the minimal simian virus 40 promoter in TCR α/β Jurkat and EL4 cells but is inactive on a V α promoter TCR γ/δ PEER and Molt-13 cells, clone 13 B cells, and HeLa fibroblasts. The enhancer has been localized to a 116-base-pair BstXI/Dra I restriction enzyme fragment, which lacks immunoglobulin octamer and κB enhancer motifs but does contain a consensus cAMP-response element (CRE). DNase I footprint analyses demonstrated that the minimal enhancer contains two binding sites for Jurkat nuclear proteins. One of these sites corresponds to the CRE, while the other does not correspond to a known transcriptional enhancer motif. These data support a model in which TCR α gene transcription is regulated by a unique set of cis-acting sequences and trans-acting factors, which are differentially active in cells of the TCR α/β lineage. In addition, the TCR α enhancer may play a role in activating oncogene expression in T-lymphoblastoid tumors that have previously been shown to display chromosomal translocations into the human TCR α locus

Energy dissipation mapping of cancer cells.

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Dutta, Diganta; Palmer, Xavier-Lewis; Kim, Jinhyun; Qian, Shizhi; Stacey, Michael

2018-02-01

The purpose of this study is to map the energy dissipation of Jurkat cells using a single 60 nanosecond pulse electric field (NsPEF), primarily through atomic force microscopy (AFM). The phase shift is generated by the sample elements that do not have a heterogeneous surface. Monitoring and manipulating the phase shift is a powerful way for determining the dissipated energy and plotting the topography. The dissipated energy is a relative value, so the silica wafer and cover slip are given a set reference while the transmission of energy between the tip of the cantilever and cell surfaces is measured. The most important finding is that the magnitude and the number of variations in the dissipated energy change with the strength of NsPEF applied. Utilizing a single low field strength NsPEF (15kV/cm), minor changes in dissipated energy were found. The application of a single high field strength NsPEF (60kV/cm) to Jurkat cells resulted in a higher dissipated energy change versus that of in the low field strength condition. Thus, the dissipated energy from the Jurkat cells changes with the strength of NsPEF. By analyzing the forces via investigation in the tapping mode of the AFM, the stabilization of the cytoskeleton and membrane of the cell are related to the strength of NsPEF applied. Furthermore, the strength of NsPEF indicates a meaningful relationship to the survival of the Jurkat cells. Copyright © 2017 Elsevier Ltd. All rights reserved.

Specific inhibition of Wee1 kinase and Rad51 recombinase: A strategy to enhance the sensitivity of leukemic T-cells to ionizing radiation-induced DNA double-strand breaks

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Havelek, Radim; Cmielova, Jana; Kralovec, Karel; Bruckova, Lenka; Bilkova, Zuzana; Fousova, Ivana; Sinkorova, Zuzana; Vavrova, Jirina; Rezacova, Martina

2014-01-01

Highlights: • Pre-treatment with the inhibitors increased the sensitivity of Jurkat cells to irradiation. • Combining both inhibitors together resulted in a G2 cell cycle arrest abrogation in Jurkat. • Jurkat cells pre-treated with inhibitors were positive for γH2AX foci 24 h upon irradiation. • Pre-treatment with Rad51 RI-1 had no effect on apoptosis induction in MOLT-4 cells. • When dosed together, the combination decreased MOLT-4 cell survival. - Abstract: Present-day oncology sees at least two-thirds of cancer patients receiving radiation therapy as a part of their anticancer treatment. The objectives of the current study were to investigate the effects of the small molecule inhibitors of Wee1 kinase II (681641) and Rad51 (RI-1) on cell cycle progression, DNA double-strand breaks repair and apoptosis following ionizing radiation exposure in human leukemic T-cells Jurkat and MOLT-4. Pre-treatment with the Wee1 681641 or Rad51 RI-1 inhibitor alone increased the sensitivity of Jurkat cells to irradiation, however combining both inhibitors together resulted in a further enhancement of apoptosis. Jurkat cells pre-treated with inhibitors were positive for γH2AX foci 24 h upon irradiation. MOLT-4 cells were less affected by inhibitors application prior to ionizing radiation exposure. Pre-treatment with Rad51 RI-1 had no effect on apoptosis induction; however Wee1 681641 increased ionizing radiation-induced cell death in MOLT-4 cells

Prometaphase arrest-dependent phosphorylation of Bcl-2 family proteins and activation of mitochondrial apoptotic pathway are associated with 17α-estradiol-induced apoptosis in human Jurkat T cells.

Science.gov (United States)

Han, Cho Rong; Jun, Do Youn; Kim, Yoon Hee; Lee, Ji Young; Kim, Young Ho

2013-10-01

In Jurkat T cell clone (JT/Neo), G2/M arrest, apoptotic sub-G1 peak, mitochondrial membrane potential (Δψm) loss, and TUNEL-positive DNA fragmentation were induced following exposure to 17α-estradiol (17α-E2), whereas none of these events (except for G2/M arrest) were induced in Jurkat cells overexpressing Bcl-2 (JT/Bcl-2). Under these conditions, phosphorylation at Thr161 and dephosphorylation at Tyr15 of Cdk1, upregulation of cyclin B1 level, histone H1 phosphorylation, Cdc25C phosphorylation at Thr-48, Bcl-2 phosphorylation at Thr-56 and Ser-70, Mcl-1 phosphorylation, and Bim phosphorylation were detected in the presence of Bcl-2 overexpression. However, the 17α-E2-induced upregulation of Bak levels, activation of Bak, activation of caspase-3, and PARP degradation were abrogated by Bcl-2 overexpression. In the presence of the G1/S blocking agent hydroxyurea, 17α-E2 failed to induce G2/M arrest and all apoptotic events including Cdk1 activation and phosphorylation of Bcl-2, Mcl-1 and Bim. The 17α-E2-induced phosphorylation of Bcl-2 family proteins and mitochondrial apoptotic events were suppressed by a Cdk1 inhibitor but not by aurora A and aurora B kinase inhibitors. Immunofluorescence microscopic analysis showed that an aberrant bipolar microtubule array, incomplete chromosome congression at the metaphase plate, and prometaphase arrest, which was reversible, were the underlying factors for 17α-E2-induced mitotic arrest. The in vitro microtubule polymerization assay showed that 17α-E2 could directly inhibit microtubule formation. These results show that the apoptogenic activity of 17α-E2 was due to the impaired mitotic spindle assembly causing prometaphase arrest and prolonged Cdk1 activation, the phosphorylation of Bcl-2, Mcl-1 and Bim, and the activation of Bak and mitochondria-dependent caspase cascade. Copyright © 2013 Elsevier B.V. All rights reserved.

Expression profiling on high-density DNA grids to detect novel targets in dendritic cells

International Nuclear Information System (INIS)

Weissmann, M.

2000-10-01

differentiation. In a first approach to select target candidates from the DC gene sample we analyzed expression patterns of stimulated and non-stimulated cell lines representing different immune phenotypes, B-cells (U266), T-cells (Jurkat) and monocytes (U937, THP1) in RNA profiling using radiolabeled complex cDNA probes. From these experiments a hit list of genes was created (data not shown) that will be prioritized towards profitable drug target by more detailed expression analysis (by means of real time PCR) and sequencing. Bioinformatics tools were implemented that enable function prediction from sequences through homology and motif searches in a high throughput mode. They were routinely applied to identify promising targets among the unknown genes. In a second approach, gene expression profiles in monocyte-derived dendritic cells (MoDCs) of various differentiation states were analyzed. Immature MoDCs, obtained after a 7 days culture of monocytes by GM-CSF and IL-4, showed the highest overlap with genes expressed in peripheral blood DCs (65 % positive spots). This is in line with a close functional relationship of both cell types. During maturation of MoDCs towards antigen-presenting cells (treatment by LPS) or tolerogenic cells (treatment by LPS/IL-10) several genes were found to be specifically up-regulated. Their potential role is being discussed. (author)

The cathepsin B inhibitor, z-FA-CMK is toxic and readily induced cell death in human T lymphocytes

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Liow, K.Y.; Chow, S.C., E-mail: chow.sek.chuen@monash.edu

2013-11-01

The cathepsin B inhibitor, benzyloxycarbonyl-phenylalanine-alanine-chloromethylketone (z-FA-CMK) was found to be toxic and readily induced cell death in the human T cell line, Jurkat, whereas two other analogs benzyloxycarbonyl-phenylalanine-alanine-fluoromethylketone (z-FA-FMK) and benzyloxycarbonyl-phenylalanine-alanine-diazomethylketone (z-FA-DMK) were not toxic. The toxicity of z-FA-CMK requires not only the CMK group, but also the presence of alanine in the P1 position and the benzyloxycarbonyl group at the N-terminal. Dose–response studies showed that lower concentrations of z-FA-CMK induced apoptosis in Jurkat T cells whereas higher concentrations induced necrosis. In z-FA-CMK-induced apoptosis, both initiator caspases (-8 and -9) and effector caspases (-3, -6 and -7) were processed to their respective subunits in Jurkat T cells. However, only the pro-form of the initiator caspases were reduced in z-FA-CMK-induced necrosis and no respective subunits were apparent. The caspase inihibitor benzyloxycarbonyl-valine-alanine-aspartic acid-(O-methyl)-fluoromehylketone (z-VAD-FMK) inhibits apoptosis and caspase processing in Jurkat T cells treated with low concentration of z-FA-CMK but has no effect on z-FA-CMK-induced necrosis and the loss of initiator caspases. This suggests that the loss of initiator caspases in Jurkat T cells during z-FA-CMK-induced necrosis is not a caspase-dependent process. Taken together, we have demonstrated that z-FA-CMK is toxic to Jurkat T cells and induces apoptosis at low concentrations, while at higher concentrations the cells die of necrosis. - Highlights: • z-FA-CMK is toxic and induce cell death in the human T cells. • z-FA-CMK toxicity requires the CMK group, alanine and the benzyloxycarbonyl group. • z-FA-CMK induced apoptosis at low concentration and necrosis at high concentration.

The cathepsin B inhibitor, z-FA-CMK is toxic and readily induced cell death in human T lymphocytes

International Nuclear Information System (INIS)

Liow, K.Y.; Chow, S.C.

2013-01-01

The cathepsin B inhibitor, benzyloxycarbonyl-phenylalanine-alanine-chloromethylketone (z-FA-CMK) was found to be toxic and readily induced cell death in the human T cell line, Jurkat, whereas two other analogs benzyloxycarbonyl-phenylalanine-alanine-fluoromethylketone (z-FA-FMK) and benzyloxycarbonyl-phenylalanine-alanine-diazomethylketone (z-FA-DMK) were not toxic. The toxicity of z-FA-CMK requires not only the CMK group, but also the presence of alanine in the P1 position and the benzyloxycarbonyl group at the N-terminal. Dose–response studies showed that lower concentrations of z-FA-CMK induced apoptosis in Jurkat T cells whereas higher concentrations induced necrosis. In z-FA-CMK-induced apoptosis, both initiator caspases (-8 and -9) and effector caspases (-3, -6 and -7) were processed to their respective subunits in Jurkat T cells. However, only the pro-form of the initiator caspases were reduced in z-FA-CMK-induced necrosis and no respective subunits were apparent. The caspase inihibitor benzyloxycarbonyl-valine-alanine-aspartic acid-(O-methyl)-fluoromehylketone (z-VAD-FMK) inhibits apoptosis and caspase processing in Jurkat T cells treated with low concentration of z-FA-CMK but has no effect on z-FA-CMK-induced necrosis and the loss of initiator caspases. This suggests that the loss of initiator caspases in Jurkat T cells during z-FA-CMK-induced necrosis is not a caspase-dependent process. Taken together, we have demonstrated that z-FA-CMK is toxic to Jurkat T cells and induces apoptosis at low concentrations, while at higher concentrations the cells die of necrosis. - Highlights: • z-FA-CMK is toxic and induce cell death in the human T cells. • z-FA-CMK toxicity requires the CMK group, alanine and the benzyloxycarbonyl group. • z-FA-CMK induced apoptosis at low concentration and necrosis at high concentration

TIM-3 Suppresses Anti-CD3/CD28-Induced TCR Activation and IL-2 Expression through the NFAT Signaling Pathway.

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Brian Tomkowicz

Full Text Available TIM-3 (T cell immunoglobulin and mucin-domain containing protein 3 is a member of the TIM family of proteins that is preferentially expressed on Th1 polarized CD4+ and CD8+ T cells. Recent studies indicate that TIM-3 serves as a negative regulator of T cell function (i.e. T cell dependent immune responses, proliferation, tolerance, and exhaustion. Despite having no recognizable inhibitory signaling motifs, the intracellular tail of TIM-3 is apparently indispensable for function. Specifically, the conserved residues Y265/Y272 and surrounding amino acids appear to be critical for function. Mechanistically, several studies suggest that TIM-3 can associate with interleukin inducible T cell kinase (ITK, the Src kinases Fyn and Lck, and the p85 phosphatidylinositol 3-kinase (PI3K adaptor protein to positively or negatively regulate IL-2 production via NF-κB/NFAT signaling pathways. To begin to address this discrepancy, we examined the effect of TIM-3 in two model systems. First, we generated several Jurkat T cell lines stably expressing human TIM-3 or murine CD28-ECD/human TIM-3 intracellular tail chimeras and examined the effects that TIM-3 exerts on T cell Receptor (TCR-mediated activation, cytokine secretion, promoter activity, and protein kinase association. In this model, our results demonstrate that TIM-3 inhibits several TCR-mediated phenotypes: i NF-kB/NFAT activation, ii CD69 expression, and iii suppression of IL-2 secretion. To confirm our Jurkat cell observations we developed a primary human CD8+ cell system that expresses endogenous levels of TIM-3. Upon TCR ligation, we observed the loss of NFAT reporter activity and IL-2 secretion, and identified the association of Src kinase Lck, and PLC-γ with TIM-3. Taken together, our results support the conclusion that TIM-3 is a negative regulator of TCR-function by attenuating activation signals mediated by CD3/CD28 co-stimulation.

Protective Role of Hsp27 Protein Against Gamma Radiation-Induced Apoptosis and Radiosensitization Effects of Hsp27 Gene Silencing in Different Human Tumor Cells

International Nuclear Information System (INIS)

Aloy, Marie-Therese; Hadchity, Elie; Bionda, Clara; Diaz-Latoud, Chantal; Claude, Line; Rousson, Robert; Arrigo, Andre-Patrick; Rodriguez-Lafrasse, Claire

2008-01-01

Purpose: The ability of heat shock protein 27 (Hsp27) to protect cells from stressful stimuli and its increased levels in tumors resistant to anticancer therapeutics suggest that it may represent a target for sensitization to radiotherapy. In this study, we investigate the protective role of Hsp27 against radiation-induced apoptosis and the effect of its attenuation in highly expressing radioresistant cancer cell lines. Methods and Materials: We examined clonogenic death and the kinetics of apoptotic events in different tumor cell lines overexpressing or underexpressing Hsp27 protein irradiated with photons. The radiosensitive Jurkat cell line, which does not express Hsp27 constitutively or in response to γ-rays, was stably transfected with Hsp27 complementary DNA. Attenuation of Hsp27 expression was accomplished by antisense or RNAi (interfering RNA) strategies in SQ20B head-and-neck squamous carcinoma, PC3 prostate cancer, and U87 glioblastoma radioresistant cells. Results: We measured concentration-dependent protection against the cytotoxic effects of radiation in Jurkat-Hsp27 cells, which led to a 50% decrease in apoptotic cells at 48 hours in the highest expressing cells. Underlying mechanisms leading to radiation resistance involved a significant increase in glutathione levels associated with detoxification of reactive oxygen species, a delay in mitochondrial collapse, and caspase activation. Conversely, attenuation of Hsp27 in SQ20B cells, characterized by their resistance to apoptosis, sensitizes cells to irradiation. This was emphasized by increased apoptosis, decreased glutathione basal level, and clonogenic cell death. Sensitization to irradiation was confirmed in PC3 and U87 radioresistant cells. Conclusion: Hsp27 gene therapy offers a potential adjuvant to radiation-based therapy of resistant tumors

Functionally important amino acids in the TCR revealed by immunoselection of membrane TCR-negative T cells

DEFF Research Database (Denmark)

Caspar-Bauguil, S; Arnaud, J; Gouaillard, C

1994-01-01

A spontaneous TCR cell surface variant (3P11) of the Jurkat T cell line is described and characterized. 3P11 was selected by incubation of Jurkat cells with anti-TCR mAb followed by passage through Ig anti-Ig columns and cloning. 3P11 contained mRNA for both Ti alpha and Ti beta and CD3 gamma, de...

Ectopic expression of AID in a non-B cell line triggers A:T and G:C point mutations in non-replicating episomal vectors.

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Tihana Jovanic

Full Text Available Somatic hypermutation (SHM of immunoglobulin genes is currently viewed as a two step process initiated by the deamination of deoxycytidine (C to deoxyuridine (U, catalysed by the activation induced deaminase (AID. Phase 1 mutations arise from DNA replication across the uracil residue or the abasic site, generated by the uracil-DNA glycosylase, yielding transitions or transversions at G:C pairs. Phase 2 mutations result from the recognition of the U:G mismatch by the Msh2/Msh6 complex (MutS Homologue, followed by the excision of the mismatched nucleotide and the repair, by the low fidelity DNA polymerase eta, of the gap generated by the exonuclease I. These mutations are mainly focused at A:T pairs. Whereas in activated B cells both G:C and A:T pairs are equally targeted, ectopic expression of AID was shown to trigger only G:C mutations on a stably integrated reporter gene. Here we show that when using non-replicative episomal vectors containing a GFP gene, inactivated by the introduction of stop codons at various positions, a high level of EGFP positive cells was obtained after transient expression in Jurkat cells constitutively expressing AID. We show that mutations at G:C and A:T pairs are produced. EGFP positive cells are obtained in the absence of vector replication demonstrating that the mutations are dependent only on the mismatch repair (MMR pathway. This implies that the generation of phase 1 mutations is not a prerequisite for the expression of phase 2 mutations.

Low toxic and high soluble camptothecin derivative 2–47 effectively induces apoptosis of tumor cells in vitro

International Nuclear Information System (INIS)

Zhou, Yao; Zhao, Hong-Ye; Jiang, Du; Wang, Lu-Yao; Xiang, Cen; Wen, Shao-Peng; Fan, Zhen-Chuan; Zhang, Yong-Min; Guo, Na; Teng, Yu-Ou; Yu, Peng

2016-01-01

The cytotoxic activity of camptothecin derivatives is so high that these compounds need to be further modified before their successful application as anti-cancer agents clinically. In this study, we reported the synthesis and biological evaluation of a novel camptothecin derivative called compound 2–47. The changes in structure did not reduce its activity to inhibit DNA topoisomerase I. Compound 2–47 induced apoptosis of many tumor cells including leukemia cells K562, Jurkat, HL-60, breast cancer cell BT-549, colon cancer cell HT-29 and liver cancer cell HepG2 with a half maximal inhibitory concentration (IC 50 ) of 2- to 3-fold lower than HCPT as a control. In particular, 2–47 inhibited the proliferation of Jurkat cells with an IC 50 of as low as 40 nM. By making use of Jurkat cell as a model, following treatment of Jurkat cells, compound 2–47 activated caspase-3 and PARP, resulting in a decreased Bcl-2/Bax ratio. These data showed that compound 2–47 induces Jurkat cell death through the mitochondrial apoptotic pathway. In addition, compound 2–47 showed a decreased cytotoxic activity against normal cells and an improved solubility in low-polar solvent. For example, compound 2–47 solutes in CHCl 3 130-fold higher than HCPT. Taken together, our data demonstrated that camptothecin derivative 2–47 notably inhibits the tumor cell proliferation through mitochondrial-mediated apoptosis in vitro. - Highlights: • Compound 2–47 showed a wide inhibitory effect on the tested tumor cell lines with an IC 50 of 3 times lower than that of HCPT in general. • Compound 2–47 inhibited the proliferation of the human leukemia cell Jurkat at an IC 50 of as low as 40 nM. • As compared to HCPT, compound 2–47 showed much reduced cytotoxicity on normal human cells. • As compared to others, compound 2–47 showed a hundreds-fold higher solubility in non-polar organic solution.

Regulation of epithelial and lymphocyte cell adhesion by adenosine deaminase-CD26 interaction.

Science.gov (United States)

Ginés, Silvia; Mariño, Marta; Mallol, Josefa; Canela, Enric I; Morimoto, Chikao; Callebaut, Christian; Hovanessian, Ara; Casadó, Vicent; Lluis, Carmen; Franco, Rafael

2002-01-01

The extra-enzymic function of cell-surface adenosine deaminase (ADA), an enzyme mainly localized in the cytosol but also found on the cell surface of monocytes, B cells and T cells, has lately been the subject of numerous studies. Cell-surface ADA is able to transduce co-stimulatory signals in T cells via its interaction with CD26, an integral membrane protein that acts as ADA-binding protein. The aim of the present study was to explore whether ADA-CD26 interaction plays a role in the adhesion of lymphocyte cells to human epithelial cells. To meet this aim, different lymphocyte cell lines (Jurkat and CEM T) expressing endogenous, or overexpressing human, CD26 protein were tested in adhesion assays to monolayers of colon adenocarcinoma human epithelial cells, Caco-2, which express high levels of cell-surface ADA. Interestingly, the adhesion of Jurkat and CEM T cells to a monolayer of Caco-2 cells was greatly dependent on CD26. An increase by 50% in the cell-to-cell adhesion was found in cells containing higher levels of CD26. Incubation with an anti-CD26 antibody raised against the ADA-binding site or with exogenous ADA resulted in a significant reduction (50-70%) of T-cell adhesion to monolayers of epithelial cells. The role of ADA-CD26 interaction in the lymphocyte-epithelial cell adhesion appears to be mediated by CD26 molecules that are not interacting with endogenous ADA (ADA-free CD26), since SKW6.4 (B cells) that express more cell-surface ADA showed lower adhesion than T cells. Adhesion stimulated by CD26 and ADA is mediated by T cell lymphocyte function-associated antigen. A role for ADA-CD26 interaction in cell-to-cell adhesion was confirmed further in integrin activation assays. FACS analysis revealed a higher expression of activated integrins on T cell lines in the presence of increasing amounts of exogenous ADA. Taken together, these results suggest that the ADA-CD26 interaction on the cell surface has a role in lymphocyte-epithelial cell adhesion. PMID

Delphinidin, a specific inhibitor of histone acetyltransferase, suppresses inflammatory signaling via prevention of NF-κB acetylation in fibroblast-like synoviocyte MH7A cells

International Nuclear Information System (INIS)

Seong, Ah-Reum; Yoo, Jung-Yoon; Choi, KyungChul; Lee, Mee-Hee; Lee, Yoo-Hyun; Lee, Jeongmin; Jun, Woojin; Kim, Sunoh; Yoon, Ho-Geun

2011-01-01

Highlights: → Delphinidin is a novel inhibitor of p300/CBP histone acetyltransferase. → Delphinidin prevents the hyperacetylation of p65 by inhibiting the HAT activity of p300/CBP. → Delphinidin efficiently suppresses the expression of inflammatory cytokines in MH7A cells via hypoacetylation of NF-κB. → Delphinidin inhibits cytokine release in the Jurkat T lymphocyte cell line. -- Abstract: Histone acetyltransferase (HAT) inhibitors (HATi) isolated from dietary compounds have been shown to suppress inflammatory signaling, which contributes to rheumatoid arthritis. Here, we identified a novel HATi in Punica granatum L. known as delphinidin (DP). DP did not affect the activity of other epigenetic enzymes (histone deacetylase, histone methyltransferase, or sirtuin1). DP specifically inhibited the HAT activities of p300/CBP. It also inhibited p65 acetylation in MH7A cells, a human rheumatoid arthritis synovial cell line. DP-induced hypoacetylation was accompanied by cytosolic accumulation of p65 and nuclear localization of IKBα. Accordingly, DP treatment inhibited TNFα-stimulated increases in NF-κB function and expression of NF-κB target genes in these cells. Importantly, DP suppressed lipopolysaccharide-induced pro-inflammatory cytokine expression in Jurkat T lymphocytes, demonstrating that HATi efficiently suppresses cytokine-mediated immune responses. Together, these results show that the HATi activity of DP counters anti-inflammatory signaling by blocking p65 acetylation and that this compound may be useful in preventing inflammatory arthritis.

Delphinidin, a specific inhibitor of histone acetyltransferase, suppresses inflammatory signaling via prevention of NF-{kappa}B acetylation in fibroblast-like synoviocyte MH7A cells

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Seong, Ah-Reum; Yoo, Jung-Yoon; Choi, KyungChul [Department of Biochemistry and Molecular Biology, Center for Chronic Metabolic Disease Research, College of Medicine, Yonsei University, Seoul (Korea, Republic of); Lee, Mee-Hee [Department of Biochemistry and Molecular Biology, Center for Chronic Metabolic Disease Research, College of Medicine, Yonsei University, Seoul (Korea, Republic of); Brain Korea 21 Project for Medical Sciences, Yonsei University, College of Medicine, Seoul (Korea, Republic of); Lee, Yoo-Hyun [Department of Food Science and Nutrition, The University of Suwon, Kyunggi-do (Korea, Republic of); Lee, Jeongmin [Department of Medical Nutrition, Kyung Hee University, Kyunggi-do (Korea, Republic of); Jun, Woojin [Department of Food and Nutrition, Chonnam National University, Gwangju (Korea, Republic of); Kim, Sunoh, E-mail: sunoh@korea.ac.kr [Jeollanamdo Institute of Natural Resources Research, Jeonnam (Korea, Republic of); Yoon, Ho-Geun, E-mail: yhgeun@yuhs.ac [Department of Biochemistry and Molecular Biology, Center for Chronic Metabolic Disease Research, College of Medicine, Yonsei University, Seoul (Korea, Republic of); Brain Korea 21 Project for Medical Sciences, Yonsei University, College of Medicine, Seoul (Korea, Republic of)

2011-07-08

Highlights: {yields} Delphinidin is a novel inhibitor of p300/CBP histone acetyltransferase. {yields} Delphinidin prevents the hyperacetylation of p65 by inhibiting the HAT activity of p300/CBP. {yields} Delphinidin efficiently suppresses the expression of inflammatory cytokines in MH7A cells via hypoacetylation of NF-{kappa}B. {yields} Delphinidin inhibits cytokine release in the Jurkat T lymphocyte cell line. -- Abstract: Histone acetyltransferase (HAT) inhibitors (HATi) isolated from dietary compounds have been shown to suppress inflammatory signaling, which contributes to rheumatoid arthritis. Here, we identified a novel HATi in Punica granatum L. known as delphinidin (DP). DP did not affect the activity of other epigenetic enzymes (histone deacetylase, histone methyltransferase, or sirtuin1). DP specifically inhibited the HAT activities of p300/CBP. It also inhibited p65 acetylation in MH7A cells, a human rheumatoid arthritis synovial cell line. DP-induced hypoacetylation was accompanied by cytosolic accumulation of p65 and nuclear localization of IKB{alpha}. Accordingly, DP treatment inhibited TNF{alpha}-stimulated increases in NF-{kappa}B function and expression of NF-{kappa}B target genes in these cells. Importantly, DP suppressed lipopolysaccharide-induced pro-inflammatory cytokine expression in Jurkat T lymphocytes, demonstrating that HATi efficiently suppresses cytokine-mediated immune responses. Together, these results show that the HATi activity of DP counters anti-inflammatory signaling by blocking p65 acetylation and that this compound may be useful in preventing inflammatory arthritis.

ChIP-on-chip analysis identifies IL-22 as direct target gene of ectopically expressed FOXP3 transcription factor in human T cells

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Jeron Andreas

2012-12-01

Full Text Available Abstract Background The transcription factor (TF forkhead box P3 (FOXP3 is constitutively expressed at high levels in naturally occurring CD4+CD25+ regulatory T cells (nTregs. It is not only the most accepted marker for that cell population but is also considered lineage determinative. Chromatin immunoprecipitation (ChIP of TFs in combination with genomic tiling microarray analysis (ChIP-on-chip has been shown to be an appropriate tool for identifying FOXP3 transcription factor binding sites (TFBSs on a genome-wide scale. In combination with microarray expression analysis, the ChIP-on-chip technique allows identification of direct FOXP3 target genes. Results ChIP-on-chip analysis of the human FOXP3 expressed in resting and PMA/ionomycin–stimulated Jurkat T cells revealed several thousand putative FOXP3 binding sites and demonstrated the importance of intronic regions for FOXP3 binding. The analysis of expression data showed that the stimulation-dependent down-regulation of IL-22 was correlated with direct FOXP3 binding in the IL-22 promoter region. This association was confirmed by real-time PCR analysis of ChIP-DNA. The corresponding ChIP-region also contained a matching FOXP3 consensus sequence. Conclusions Knowledge of the general distribution patterns of FOXP3 TFBSs in the human genome under resting and activated conditions will contribute to a better understanding of this TF and its influence on direct target genes, as well as its importance for the phenotype and function of Tregs. Moreover, FOXP3-dependent repression of Th17-related IL-22 may be relevant to an understanding of the phenomenon of Treg/Th17 cell plasticity.

Construction of Egr1-mediated human truncated apoptosis inducing factor expression vector and its expression regularity induced by radiation in breast cancer MCF-7 cells

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Wang Jianfeng; Gong Shouliang; Wang Zhicheng; Fang Fang; Liu Yang; Wu Jiahui

2012-01-01

Objective: To clone human truncated apoptosis inducing factor (AIF) cDNA sequence, and to construct early growth response 1 (Egr1)-mediated recombinant expression vector pcDNA 3.1-Egr1-AIF Δ1-480 (pEgr1-AIFΔ 1-480 ), and to observe its regularity induced by radiation in human breast cancer MCF-7 cells. Methods: The total mRNA extracted from human leukemia Jurkat cells used as template, and the human AIFΔ 1-480 was acquired by RT-PCR, and it was linked to pMD18T vector for sequencing. Egr1 fragment was digested from pMD19T-Egr1 by restrictive enzyme, and the Egr1-mediated expression plasmid pEgr1-AIFΔ 1-480 was constructed by gene recombination. There were control group, pcDNA3.1 group, pAIFΔ 1-480 group and pEgr1-AIFΔ 1-480 group in the experiment. After the plasmids in various groups were transfected into human breast cancer MCF-7 cells, the AIF and AIFΔ 1-480 protein expression time-effect (0, 2, 4, 12, 24 and 48 h after 2.0 Gy irradiation) and dose-effect (24 h after 0, 0.2, 0.5, 1.0, 2.0 and 5.0 Gy irradiation) regularity were measured by Western blotting method. Results: The sequencing results showed that the AIFΔ 1-480 acquired by RT-PCR was consistent with the sequence expected, the pEgr-AIFΔ 1-480 was confirmed by PCR and restrictive enzyme digestion. After 0-48 h the MCF-7 cells were irradiated by 2.0 Gy, and the AIF protein expressed in the cells in each group, and it increased significantly from 4 h and the AIF expressions in 4, 12, 24 and 48 h groups were higher than that in 0 h group (P<0.05), and it reached to maximum value at 48 h. But the AIFΔ 1-480 protein expressed in the cells in pAIFΔ 1-480 and pEgr1-AIFΔ 1-480 groups from 2 h (P<0.05), and it reached to peak value at 24 h. The AIFΔ 1-480 expressions in pEgr1-AIFΔ 1-480 group were higher than those in pAIFΔ 1-480 group at and 48 h (P<0.05). After the MCF-7 cells were irradiated by 0-5 Gy for 24 h, the AIF protein expressed in the cells in each group, but the AIFΔ 1-480 protein

Monocyte-lymphocyte fusion induced by the HIV-1 envelope generates functional heterokaryons with an activated monocyte-like phenotype

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Martínez-Méndez, David; Rivera-Toledo, Evelyn; Ortega, Enrique; Licona-Limón, Ileana; Huerta, Leonor

2017-01-01

Enveloped viruses induce cell-cell fusion when infected cells expressing viral envelope proteins interact with target cells, or through the contact of cell-free viral particles with adjoining target cells. CD4"+ T lymphocytes and cells from the monocyte-macrophage lineage express receptors for HIV envelope protein. We have previously reported that lymphoid Jurkat T cells expressing the HIV-1 envelope protein (Env) can fuse with THP-1 monocytic cells, forming heterokaryons with a predominantly myeloid phenotype. This study shows that the expression of monocytic markers in heterokaryons is stable, whereas the expression of lymphoid markers is mostly lost. Like THP-1 cells, heterokaryons exhibited FcγR-dependent phagocytic activity and showed an enhanced expression of the activation marker ICAM-1 upon stimulation with PMA. In addition, heterokaryons showed morphological changes compatible with maturation, and high expression of the differentiation marker CD11b in the absence of differentiation-inducing agents. No morphological change nor increase in CD11b expression were observed when an HIV-fusion inhibitor blocked fusion, or when THP-1 cells were cocultured with Jurkat cells expressing a non-fusogenic Env protein, showing that differentiation was not induced merely by cell-cell interaction but required cell-cell fusion. Inhibition of TLR2/TLR4 signaling by a TIRAP inhibitor greatly reduced the expression of CD11b in heterokaryons. Thus, lymphocyte-monocyte heterokaryons induced by HIV-1 Env are stable and functional, and fusion prompts a phenotype characteristic of activated monocytes via intracellular TLR2/TLR4 signaling. - Highlights: • Jurkat T cells expressing the HIV-1 envelope fuse with THP-1 monocytes. • Heterokaryons display a dominant myeloid phenotype and monocyte function. • Heterokaryons exhibit activation features in the absence of activation agents. • Activation is not due to cell-cell interaction but requires cell-cell fusion. • The

Monocyte-lymphocyte fusion induced by the HIV-1 envelope generates functional heterokaryons with an activated monocyte-like phenotype

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Martínez-Méndez, David; Rivera-Toledo, Evelyn; Ortega, Enrique; Licona-Limón, Ileana; Huerta, Leonor, E-mail: leonorhh@biomedicas.unam.mx

2017-03-01

Enveloped viruses induce cell-cell fusion when infected cells expressing viral envelope proteins interact with target cells, or through the contact of cell-free viral particles with adjoining target cells. CD4{sup +} T lymphocytes and cells from the monocyte-macrophage lineage express receptors for HIV envelope protein. We have previously reported that lymphoid Jurkat T cells expressing the HIV-1 envelope protein (Env) can fuse with THP-1 monocytic cells, forming heterokaryons with a predominantly myeloid phenotype. This study shows that the expression of monocytic markers in heterokaryons is stable, whereas the expression of lymphoid markers is mostly lost. Like THP-1 cells, heterokaryons exhibited FcγR-dependent phagocytic activity and showed an enhanced expression of the activation marker ICAM-1 upon stimulation with PMA. In addition, heterokaryons showed morphological changes compatible with maturation, and high expression of the differentiation marker CD11b in the absence of differentiation-inducing agents. No morphological change nor increase in CD11b expression were observed when an HIV-fusion inhibitor blocked fusion, or when THP-1 cells were cocultured with Jurkat cells expressing a non-fusogenic Env protein, showing that differentiation was not induced merely by cell-cell interaction but required cell-cell fusion. Inhibition of TLR2/TLR4 signaling by a TIRAP inhibitor greatly reduced the expression of CD11b in heterokaryons. Thus, lymphocyte-monocyte heterokaryons induced by HIV-1 Env are stable and functional, and fusion prompts a phenotype characteristic of activated monocytes via intracellular TLR2/TLR4 signaling. - Highlights: • Jurkat T cells expressing the HIV-1 envelope fuse with THP-1 monocytes. • Heterokaryons display a dominant myeloid phenotype and monocyte function. • Heterokaryons exhibit activation features in the absence of activation agents. • Activation is not due to cell-cell interaction but requires cell-cell fusion. • The

Low toxic and high soluble camptothecin derivative 2–47 effectively induces apoptosis of tumor cells in vitro

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Zhou, Yao; Zhao, Hong-Ye; Jiang, Du; Wang, Lu-Yao; Xiang, Cen; Wen, Shao-Peng [Key Laboratory of Industrial Fermentation Microbiology, Tianjin Key Laboratory of Industrial Microbiology, Sino-French Joint Laboratory of Food Nutrition, Safety and Medicinal Chemistry, Tianjin University of Science and Technology, Tianjin 300457 (China); Fan, Zhen-Chuan [Key Laboratory of Food Nutrition and Safety, Tianjin University of Science & Technology, Ministry of Education, Tianjin, 300457 (China); Obesita & Algaegen LLC, College Station, TX 77845 (United States); Zhang, Yong-Min [Université Pierre et Marie Curie-Paris 6, Institut Parisien de Chimie Moléculaire UMR CNRS 8232, 4 place Jussieu, 75005, Paris (France); Guo, Na [Key Laboratory of Industrial Fermentation Microbiology, Tianjin Key Laboratory of Industrial Microbiology, Sino-French Joint Laboratory of Food Nutrition, Safety and Medicinal Chemistry, Tianjin University of Science and Technology, Tianjin 300457 (China); Teng, Yu-Ou, E-mail: tyo201485@tust.edu.cn [Key Laboratory of Industrial Fermentation Microbiology, Tianjin Key Laboratory of Industrial Microbiology, Sino-French Joint Laboratory of Food Nutrition, Safety and Medicinal Chemistry, Tianjin University of Science and Technology, Tianjin 300457 (China); Yu, Peng, E-mail: yupeng@tust.edu.cn [Key Laboratory of Industrial Fermentation Microbiology, Tianjin Key Laboratory of Industrial Microbiology, Sino-French Joint Laboratory of Food Nutrition, Safety and Medicinal Chemistry, Tianjin University of Science and Technology, Tianjin 300457 (China)

2016-04-08

The cytotoxic activity of camptothecin derivatives is so high that these compounds need to be further modified before their successful application as anti-cancer agents clinically. In this study, we reported the synthesis and biological evaluation of a novel camptothecin derivative called compound 2–47. The changes in structure did not reduce its activity to inhibit DNA topoisomerase I. Compound 2–47 induced apoptosis of many tumor cells including leukemia cells K562, Jurkat, HL-60, breast cancer cell BT-549, colon cancer cell HT-29 and liver cancer cell HepG2 with a half maximal inhibitory concentration (IC{sub 50}) of 2- to 3-fold lower than HCPT as a control. In particular, 2–47 inhibited the proliferation of Jurkat cells with an IC{sub 50} of as low as 40 nM. By making use of Jurkat cell as a model, following treatment of Jurkat cells, compound 2–47 activated caspase-3 and PARP, resulting in a decreased Bcl-2/Bax ratio. These data showed that compound 2–47 induces Jurkat cell death through the mitochondrial apoptotic pathway. In addition, compound 2–47 showed a decreased cytotoxic activity against normal cells and an improved solubility in low-polar solvent. For example, compound 2–47 solutes in CHCl{sub 3} 130-fold higher than HCPT. Taken together, our data demonstrated that camptothecin derivative 2–47 notably inhibits the tumor cell proliferation through mitochondrial-mediated apoptosis in vitro. - Highlights: • Compound 2–47 showed a wide inhibitory effect on the tested tumor cell lines with an IC{sub 50} of 3 times lower than that of HCPT in general. • Compound 2–47 inhibited the proliferation of the human leukemia cell Jurkat at an IC{sub 50} of as low as 40 nM. • As compared to HCPT, compound 2–47 showed much reduced cytotoxicity on normal human cells. • As compared to others, compound 2–47 showed a hundreds-fold higher solubility in non-polar organic solution.

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

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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.

Profiles of Gene Expression Induced by Ionizing Radiation in Different Human Cell Types. Doctoral thesis prepared at SCK-CEN and defended in 2005

International Nuclear Information System (INIS)

Mori, M.

2006-01-01

Ionizing radiation disrupts chemical bonds in biomolecules, such as proteins and DNA, which result in important cellular damage. Exposure to relatively high doses of ionizing radiation such as those delivered to the tumor in a radiotherapy protocol is generally lethal for the cell. However, non-lethal dose of ionizing radiation can be delivered during radiotherapy to the healthy tissue surrounding the tumor. Although the effects of ionizing radiation at the cellular level are quite well established (cell cycle arrest, senescence, apoptosis, mitotic catastrophe), questions remain concerning the molecular pathways regulating these cellular responses, including those differentiating the responses between tumor and normal cells. In normal cells, the p53 protein plays a central role. However, the efficacy of radiation treatments on tumor cells is often reduced because of the frequent inactivation of the p53 protein in those cells. Our study used the microarray technology to investigate the molecular pathways induced by irradiation in transformed and nontransformed human cells. Profiles of gene expression obtained with cDNA microarrays were regarded as steps to characterize the general response to ionizing radiation and, possibly also, differentiating the response between transformed and nontransformed cells. Possible implications of such research include the development of radiosensitizing (to maximize the effect of radiotherapeutic irradiation) and of radioprotecting strategies. Transcriptional profiles were investigated in transformed (Jurkat, HL60) and non-transformed (freshly isolated lymphocyte subpopulations) cells of hematopoietic origin. Also, because HeLa carcinoma-derived cells expressing human papilloma virus (HPV) 18 derived E2 protein represent a reliable model to study the p53 pathway, which is normally activated in response to radiation, molecular profiles were obtained to characterize this pathway in these cells

The Interaction of CD154 with the α5β1 Integrin Inhibits Fas-Induced T Cell Death.

Science.gov (United States)

Bachsais, Meriem; Naddaf, Nadim; Yacoub, Daniel; Salti, Suzanne; Alaaeddine, Nada; Aoudjit, Fawzi; Hassan, Ghada S; Mourad, Walid

2016-01-01

CD154, a critical regulator of the immune response, is usually associated with chronic inflammatory, autoimmune diseases as well as malignant disorders. In addition to its classical receptor CD40, CD154 is capable of binding other receptors, members of the integrin family, the αIIbβ3, αMβ2 and α5β1. Given the role attributed to integrins and particularly the β1 integrins in inhibiting apoptotic events in normal as well as malignant T cells, we were highly interested in investigating the role of the CD154/α5β1 interaction in promoting survival of malignant T cells contributing as such to tumor development and/or propagation. To support our hypothesis, we first show that soluble CD154 binds to the T-cell acute lymphoblastic leukemia cell line, Jurkat E6.1 in a α5β1-dependent manner. Binding of soluble CD154 to α5β1 integrin of Jurkat cells leads to the activation of key survival proteins, including the p38 and ERK1/2 mitogen-activated protein kinases (MAPKs), phosphoinositide 3 kinase (PI-3K), and Akt. Interestingly, soluble CD154 significantly inhibits Fas-mediated apoptosis in T cell leukemia-lymphoma cell lines, Jurkat E6.1 and HUT78 cells, an important hallmark of T cell survival during malignancy progression. These anti-apoptotic effects were mainly mediated by the activation of the PI-3K/Akt pathway but also involved the p38 and the ERK1/2 MAPKs cascades. Our data also demonstrated that the CD154-triggered inhibition of the Fas-mediated cell death response was dependent on a suppression of caspase-8 cleavage, but independent of de novo protein synthesis or alterations in Fas expression on cell surface. Together, our results highlight the impact of the CD154/α5β1 interaction in T cell function/survival and identify novel targets for the treatment of malignant disorders, particularly of T cell origin.

The Interaction of CD154 with the α5β1 Integrin Inhibits Fas-Induced T Cell Death.

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Meriem Bachsais

Full Text Available CD154, a critical regulator of the immune response, is usually associated with chronic inflammatory, autoimmune diseases as well as malignant disorders. In addition to its classical receptor CD40, CD154 is capable of binding other receptors, members of the integrin family, the αIIbβ3, αMβ2 and α5β1. Given the role attributed to integrins and particularly the β1 integrins in inhibiting apoptotic events in normal as well as malignant T cells, we were highly interested in investigating the role of the CD154/α5β1 interaction in promoting survival of malignant T cells contributing as such to tumor development and/or propagation. To support our hypothesis, we first show that soluble CD154 binds to the T-cell acute lymphoblastic leukemia cell line, Jurkat E6.1 in a α5β1-dependent manner. Binding of soluble CD154 to α5β1 integrin of Jurkat cells leads to the activation of key survival proteins, including the p38 and ERK1/2 mitogen-activated protein kinases (MAPKs, phosphoinositide 3 kinase (PI-3K, and Akt. Interestingly, soluble CD154 significantly inhibits Fas-mediated apoptosis in T cell leukemia-lymphoma cell lines, Jurkat E6.1 and HUT78 cells, an important hallmark of T cell survival during malignancy progression. These anti-apoptotic effects were mainly mediated by the activation of the PI-3K/Akt pathway but also involved the p38 and the ERK1/2 MAPKs cascades. Our data also demonstrated that the CD154-triggered inhibition of the Fas-mediated cell death response was dependent on a suppression of caspase-8 cleavage, but independent of de novo protein synthesis or alterations in Fas expression on cell surface. Together, our results highlight the impact of the CD154/α5β1 interaction in T cell function/survival and identify novel targets for the treatment of malignant disorders, particularly of T cell origin.

Advanced Data Mining of Leukemia Cells Micro-Arrays

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Richard S. Segall

2009-12-01

Full Text Available This paper provides continuation and extensions of previous research by Segall and Pierce (2009a that discussed data mining for micro-array databases of Leukemia cells for primarily self-organized maps (SOM. As Segall and Pierce (2009a and Segall and Pierce (2009b the results of applying data mining are shown and discussed for the data categories of microarray databases of HL60, Jurkat, NB4 and U937 Leukemia cells that are also described in this article. First, a background section is provided on the work of others pertaining to the applications of data mining to micro-array databases of Leukemia cells and micro-array databases in general. As noted in predecessor article by Segall and Pierce (2009a, micro-array databases are one of the most popular functional genomics tools in use today. This research in this paper is intended to use advanced data mining technologies for better interpretations and knowledge discovery as generated by the patterns of gene expressions of HL60, Jurkat, NB4 and U937 Leukemia cells. The advanced data mining performed entailed using other data mining tools such as cubic clustering criterion, variable importance rankings, decision trees, and more detailed examinations of data mining statistics and study of other self-organized maps (SOM clustering regions of workspace as generated by SAS Enterprise Miner version 4. Conclusions and future directions of the research are also presented.

Proteomic profiling of the human T-cell nucleolus.

Science.gov (United States)

Jarboui, Mohamed Ali; Wynne, Kieran; Elia, Giuliano; Hall, William W; Gautier, Virginie W

2011-12-01

The nucleolus, site of ribosome biogenesis, is a dynamic subnuclear organelle involved in diverse cellular functions. The size, number and organisation of nucleoli are cell-specific and while it remains to be established, the nucleolar protein composition would be expected to reflect lineage-specific transcriptional regulation of rDNA genes and have cell-type functional components. Here, we describe the first characterisation of the human T-cell nucleolar proteome. Using the Jurkat T-cell line and a reproducible organellar proteomic approach, we identified 872 nucleolar proteins. In addition to ribosome biogenesis and RNA processing networks, network modeling and topological analysis of nucleolar proteome revealed distinct macromolecular complexes known to orchestrate chromatin structure and to contribute to the regulation of gene expression, replication, recombination and repair, and chromosome segregation. Furthermore, among our dataset, we identified proteins known to functionally participate in T-cell biology, including RUNX1, ILF3, ILF2, STAT3, LSH, TCF-1, SATB1, CTCF, HMGB3, BCLAF1, FX4L1, ZAP70, TIAM1, RAC2, THEMIS, LCP1, RPL22, TOPK, RETN, IFI-16, MCT-1, ISG15, and 14-3-3τ, which support cell-specific composition of the Jurkat nucleolus. Subsequently, the nucleolar localisation of RUNX1, ILF3, STAT3, ZAP70 and RAC2 was further validated by Western Blot analysis and immunofluorescence microscopy. Overall, our T-cell nucleolar proteome dataset not only further expands the existing repertoire of the human nucleolar proteome but support a cell type-specific composition of the nucleolus in T cell and highlights the potential roles of the nucleoli in lymphocyte biology. Copyright © 2011 Elsevier Ltd. All rights reserved.

Molecular requirements for the combined effects of TRAIL and ionising radiation

International Nuclear Information System (INIS)

Marini, Patrizia; Jendrossek, Verena; Durand, Elise; Gruber, Charlotte; Budach, Wilfried; Belka, Claus

2003-01-01

Background and purpose: Previously it was shown that combination of death ligand TRAIL and irradiation strongly increases cell kill in several human tumour cell lines. Since Bcl-2 overexpression did not strongly interfere with the efficacy, components of the mitochondrial death pathway are not required for an effective combined treatment. In the present study the minimal molecular prerequisites for the efficacy of a combined treatment were determined. Materials and methods: Apoptosis induction in control, caspase-8 and FADD negative Jurkat cells, BJAB control and FADD-DN cells was analysed by FACS. Activation of caspase-8, -10 and -3 and cleavage of PARP was determined by immunoblotting. TRAIL receptors were activated using recombinant human TRAIL. Surface expression of TRAIL receptors DR4 and DR5 was analysed by FACS. Results: Jurkat T-cells express the agonistic DR5 receptor but not DR4. Presence of FADD was found to be essential for TRAIL induced apoptosis. Caspase-8 negative cells show very low rates of apoptosis after prolonged stimulation with TRAIL. No combined effects of TRAIL with irradiation could be found in FADD-DN over expressing and FADD deficient cells. However, the combination of TRAIL and irradiation clearly lead to a combined effect in caspase-8 negative Jurkat cells, albeit with reduced death rates. In these cells activation of the alternative initiator caspase-10 could be detected after combined treatment. Conclusion: Our data show that a combined therapy with TRAIL and irradiation will only be effective in cells expressing at least one agonistic TRAIL receptor, FADD and caspase-8 or caspase-10

Zerumbone-loaded nanostructured lipid carrier induces G2/M cell cycle arrest and apoptosis via mitochondrial pathway in a human lymphoblastic leukemia cell line

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Rahman HS

2014-01-01

Full Text Available Heshu Sulaiman Rahman,1–3 Abdullah Rasedee,1,2 Ahmad Bustamam Abdul,2,4 Nazariah Allaudin Zeenathul,1,2 Hemn Hassan Othman,1,3 Swee Keong Yeap,2 Chee Wun How,2 Wan Abd Ghani Wan Nor Hafiza4,51Faculty of Veterinary Medicine, 2Institute of Bioscience, Universiti Putra Malaysia, Selangor, Malaysia; 3Faculty of Veterinary Medicine, University of Sulaimanyah, Sulaimanyah City, Kurdistan Region, Northern Iraq; 4Faculty of Medicine and Health Science, Universiti Putra Malaysia, Selangor, Malaysia; 5College of Medical Laboratory Technology, Institute for Medical Research, Kuala Lumpur, MalaysiaAbstract: This investigation evaluated the antileukemia properties of a zerumbone (ZER-loaded nanostructured lipid carrier (NLC prepared by hot high-pressure homogenization techniques in an acute human lymphoblastic leukemia (Jurkat cell line in vitro. The apoptogenic effect of the ZER-NLC on Jurkat cells was determined by fluorescent and electron microscopy, Annexin V-fluorescein isothiocyanate, Tdt-mediated dUTP nick-end labeling assay, cell cycle analysis, and caspase activity. An MTT (3-(4,5-dimethylthiazol-2-yl-2,5 diphenyltetrazolium bromide assay showed that ZER-NLC did not have adverse effects on normal human peripheral blood mononuclear cells. ZER-NLC arrested the Jurkat cells at G2/M phase with inactivation of cyclin B1 protein. The study also showed that the antiproliferative effect of ZER-NLC on Jurkat cells is through the intrinsic apoptotic pathway via activation of caspase-3 and caspase-9, release of cytochrome c from the mitochondria into the cytosol, and subsequent cleavage of poly (adenosine diphosphate-ribose polymerase (PARP. These findings show that the ZER-NLC is a potentially useful treatment for acute lymphoblastic leukemia in humans.Keywords: zerumbone-loaded nanostructured lipid carrier, cell cycle arrest, apoptosis, mitochondrial pathway

Cytotoxicity of diacetoxyscirpenol is associated with apoptosis by activation of caspase-8 and interruption of cell cycle progression by down-regulation of cdk4 and cyclin B1 in human Jurkat T cells

International Nuclear Information System (INIS)

Jun, Do Youn; Kim, Jun Seok; Park, Hae Sun; Song, Woo Sun; Bae, Young Seuk; Kim, Young Ho

2007-01-01

To understand the mechanism underlying T-cell toxicity of diacetoxyscirpenol (DAS) from Fusarium sambucinum, its apoptogenic as well as growth retardation activity was investigated in human Jurkat T cells. Exposure to DAS (0.01-0.15 μM) caused apoptotic DNA fragmentation along with caspase-8 activation, Bid cleavage, mitochondrial cytochrome c release, activation of caspase-9 and caspase-3, and PARP degradation, without any alteration in the levels of Fas or FasL. Under these conditions, necrosis was not accompanied. The cytotoxicity of DAS was not blocked by the anti-Fas neutralizing antibody ZB-4. Although the DAS-induced apoptotic events were completely prevented by overexpression of Bcl-xL, the cells overexpressing Bcl-xL were unable to divide in the presence of DAS, resulting from the failure of cell cycle progression possibly due to down-regulation in the protein levels of cdk4 and cyclin B1. The DAS-mediated apoptosis and activation of caspase-8, -9, and -3 were abrogated by either pan-caspase inhibitor (z-VAD-fmk) or caspase-8 inhibitor (z-IETD-fmk). While the DAS-mediated apoptosis and activation of caspase-9 and caspase-3 were slightly suppressed by the mitochondrial permeability transition pore inhibitor (CsA), both caspase-8 activation and Bid cleavage were not affected by CsA. The activated normal peripheral T cells possessed a similar susceptibility to the cytotoxicity of DAS. These results demonstrate that the T-cell toxicity of DAS is attributable to not only apoptosis initiated by caspase-8 activation and subsequent mitochondrion-dependent or -independent activation of caspase cascades, which can be regulated by Bcl-xL, but also interruption of cell cycle progression caused by down-regulation of cdk4 and cyclin B1 proteins

Intracellular high mobility group B1 protein (HMGB1) represses HIV-1 LTR-directed transcription in a promoter- and cell-specific manner

International Nuclear Information System (INIS)

Naghavi, Mojgan H.; Nowak, Piotr; Andersson, Jan; Soennerborg, Anders; Yang Huan; Tracey, Kevin J.; Vahlne, Anders

2003-01-01

We investigated whether the high mobility group B 1 (HMGB1), an abundant nuclear protein in all mammalian cells, affects HIV-1 transcription. Intracellular expression of human HMGB1 repressed HIV-1 gene expression in epithelial cells. This inhibitory effect of HMGB1 was caused by repression of long terminal repeat (LTR)-mediated transcription. Other viral promoters/enhancers, including simian virus 40 or cytomegalovirus, were not inhibited by HMGB1. In addition, HMGB1 inhibition of HIV-1 subtype C expression was dependent on the number of NFκB sites in the LTR region. The inhibitory effect of HMGB1 on viral gene expression observed in HeLa cells was confirmed by an upregulation of viral replication in the presence of antisense HMGB1 in monocytic cells. In contrast to what was found in HeLa cells and monocytic cells, endogenous HMGB1 expression did not affect HIV-1 replication in unstimulated Jurkat cells. Thus, intracellular HMGB1 affects HIV-1 LTR-directed transcription in a promoter- and cell-specific manner

Suppression of postmitochondrial signaling and delayed response to UV-induced nuclear apoptosis in HeLa cells

International Nuclear Information System (INIS)

Sasai, Kaori; Yajima, Hirohiko; Suzuki, Fumio

2002-01-01

Activation of postmitochondrial pathways by UV irradiation was examined using mouse lymphoma 3SB and human leukemic Jurkat cells and two human carcinoma cell lines (HeLa and MCF-7). Exposure of 3SB and Jurkat cells resulted in large amounts of cytochrome c and apoptosis-inducing factor (AIF) being released into the cytosol, and a clear laddering pattern of DNA fragments was observed within 3 h of incubation after irradiation. Simultaneously, activation of caspase-9 and its downstream caspases was detected. HeLa and MCF-7 cells also showed extensive release of mitochondrial factors and caspase-9 activation at 4 to 6 h after exposure, but apoptotic nuclear changes appeared much later. Compared with 3SB and Jurkat cells, these carcinoma cell lines exhibited reduced activation of caspase-9-like proteolytic activity by UV radiation, and levels of caspase-3-like activity in HeLa cells were extremely low, similar to those in caspase-3-deficient MCF-7 cells. These results suggest that the delayed response to UV-induced nuclear apoptosis in HeLa cells is due to a reduced activation of the caspase cascade downstream of cytochrome c release and suppression of caspase-3 activity. (author)

Cooperativity of CD44 and CD49d in leukemia cell homing, migration, and survival offers a means for therapeutic attack.

Science.gov (United States)

Singh, Vibuthi; Erb, Ulrike; Zöller, Margot

2013-11-15

A CD44 blockade drives leukemic cells into differentiation and apoptosis by dislodging from the osteogenic niche. Because anti-CD49d also supports hematopoietic stem cell mobilization, we sought to determine the therapeutic efficacy of a joint CD49d/CD44 blockade. To unravel the underlying mechanism, the CD49d(-) EL4 lymphoma was transfected with CD49d or point-mutated CD49d, prohibiting phosphorylation and FAK binding; additionally, a CD44(-) Jurkat subline was transfected with murine CD44, CD44 with a point mutation in the ezrin binding site, or with cytoplasmic tail-truncated CD44. Parental and transfected EL4 and Jurkat cells were evaluated for adhesion, migration, and apoptosis susceptibility in vitro and in vivo. Ligand-binding and Ab-blocking studies revealed CD44-CD49d cooperation in vitro and in vivo in adhesion, migration, and apoptosis resistance. The cooperation depends on ligand-induced proximity such that both CD44 and CD49d get access to src, FAK, and paxillin and via lck to the MAPK pathway, with the latter also supporting antiapoptotic molecule liberation. Accordingly, synergisms were only seen in leukemia cells expressing wild-type CD44 and CD49d. Anti-CD44 together with anti-CD49d efficiently dislodged EL4-CD49d/Jurkat-CD44 in bone marrow and spleen. Dislodging was accompanied by increased apoptosis susceptibility that strengthened low-dose chemotherapy, the combined treatment most strongly interfering with metastatic settlement and being partly curative. Ab treatment also promoted NK and Ab-dependent cellular cytotoxicity activation, which affected leukemia cells independent of CD44/CD49d tail mutations. Thus, mostly owing to a blockade of joint signaling, anti-CD44 and anti-CD49d hamper leukemic cell settlement and break apoptosis resistance, which strongly supports low-dose chemotherapy.

Cellular determinants involving mitochondrial dysfunction, oxidative stress and apoptosis correlate with the synergic cytotoxicity of epigallocatechin-3-gallate and menadione in human leukemia Jurkat T cells.

Science.gov (United States)

Tofolean, Ioana Teodora; Ganea, Constanta; Ionescu, Diana; Filippi, Alexandru; Garaiman, Alexandru; Goicea, Alexandru; Gaman, Mihnea-Alexandru; Dimancea, Alexandru; Baran, Irina

2016-01-01

We have investigated the growth-suppressive action of epigallocatechin-3-gallate (EGCG) on human leukemia Jurkat T cells. Results show a strong correlation between the dose-dependent reduction of clonogenic survival following acute EGCG treatments and the EGCG-induced decline of the mitochondrial level of Ca(2+). The cell killing ability of EGCG was synergistically enhanced by menadione. In addition, the cytotoxic effect of EGCG applied alone or in combination with menadione was accompanied by apoptosis induction. We also observed that in acute treatments EGCG displays strong antioxidant properties in the intracellular milieu, but concurrently triggers some oxidative stress generating mechanisms that can fully develop on a longer timescale. In parallel, EGCG dose-dependently induced mitochondrial depolarization during exposure, but this condition was subsequently reversed to a persistent hyperpolarized mitochondrial state that was dependent on the activity of respiratory Complex I. Fluorimetric measurements suggest that EGCG is a mitochondrial Complex III inhibitor and indicate that EGCG evokes a specific cellular fluorescence with emission at 400nm and two main excitation bands (at 330nm and 350nm) that may originate from a mitochondrial supercomplex containing dimeric Complex III and dimeric ATP-synthase, and therefore could provide a valuable means to characterize the functional properties of the respiratory chain. Copyright © 2015 Elsevier Ltd. All rights reserved.

The role of heat shock protein 90 in the regulation of tumor cell apoptosis.

Science.gov (United States)

Kaigorodova, E V; Ryazantseva, N V; Novitskii, V V; Belkina, M V; Maroshkina, A N

2011-02-01

Programmed death of Jurkat tumor cells was studied under conditions of culturing with 17-AAG selective inhibitor of heat shock protein with a molecular weight of 90 kDa and etoposide. Apoptosis realization was evaluated by fluorescent microscopy with FITC-labeled annexin V and propidium iodide. Activity of caspase-3 was evaluated spectrophotometrically. Inhibition of heat shock protein with a molecular weight of 90 kDa activated the apoptotic program in Jurkat tumor cells and etoposide-induced apoptosis. The heat shock protein with a molecular weight of 90 kDa acted as apoptosis inhibitor in tumor cells.

N-acetylphytosphingosine enhances the radiosensitivity of tumor cells by increasing apoptosis

International Nuclear Information System (INIS)

Han, Y.; Kim, Y.; Yun, Y.; Jeon, S.; Kim, K.; Song, J.; Hong, S.H.; Park, C.

2005-01-01

Ceramides are well-known second messengers which mediate apoptosis, proliferation, differentiation in mammalian cells, but the physiological roles of phytosphingosines are poorly understood. We hypothesized that one of the phytosphingosine derivatives, N-acetylphytosphingosine (NAPS) can induce apoptosis in human leukemia Jurkat cell line and increase apoptosis in irradiated MDA-MB-231 cells. We first examined the effect of NAPS on apoptosis of Jurkat cells. NAPS had a more rapid and stronger apoptotic effect than C 2 -ceramide in Jurkat cells and significant increase of apoptosis was observed at 3 h after treatment. In contrast, the apoptosis induced by C2-ceramide was observed only after 16 h of treatment. NAPS induced apoptosis was mediated by caspase 3 and 8 activation and inhibited by z-VAD-fmk. Ceramide plays a pivotal role in radiation induced apoptosis. We postulated that exogenous treatment of NAPS sensitizes tumor cells to ionizing radiation, since NAPS might be used as a more effective alternative to C2-ceramide. As expected, NAPS decreased clonogenic survival of irradiated MDA-MB-231 cells dose dependently, and apoptosis of irradiated cells in the presence of NAPS was increased through the caspase activation. Taken together, NAPS is an effective apoptosis-inducing agent, which can be readily synthesized from yeast sources, and is a potent alternative to ceramide for the further study of ceramide associated signaling and the development of radiosensitizing agent. (orig.)

Nanosecond pulsed electric fields induce poly(ADP-ribose) formation and non-apoptotic cell death in HeLa S3 cells

Energy Technology Data Exchange (ETDEWEB)

Morotomi-Yano, Keiko; Akiyama, Hidenori [Institute of Pulsed Power Science, Kumamoto University, Kumamoto 860-8555 (Japan); Yano, Ken-ichi, E-mail: yanoken@kumamoto-u.ac.jp [Priority Organization for Innovation and Excellence, Kumamoto University, Kumamoto 860-8555 (Japan)

2013-08-30

Highlights: •Nanosecond pulsed electric field (nsPEF) is a new and unique means for life sciences. •Apoptosis was induced by nsPEF exposure in Jurkat cells. •No signs of apoptosis were detected in HeLa S3 cells exposed to nsPEFs. •Formation of poly(ADP-ribose) was induced in nsPEF-exposed HeLa S3 cells. •Two distinct modes of cell death were activated by nsPEF in a cell-dependent manner. -- Abstract: Nanosecond pulsed electric fields (nsPEFs) have recently gained attention as effective cancer therapy owing to their potency for cell death induction. Previous studies have shown that apoptosis is a predominant mode of nsPEF-induced cell death in several cell lines, such as Jurkat cells. In this study, we analyzed molecular mechanisms for cell death induced by nsPEFs. When nsPEFs were applied to Jurkat cells, apoptosis was readily induced. Next, we used HeLa S3 cells and analyzed apoptotic events. Contrary to our expectation, nsPEF-exposed HeLa S3 cells exhibited no molecular signs of apoptosis execution. Instead, nsPEFs induced the formation of poly(ADP-ribose) (PAR), a hallmark of necrosis. PAR formation occurred concurrently with a decrease in cell viability, supporting implications of nsPEF-induced PAR formation for cell death. Necrotic PAR formation is known to be catalyzed by poly(ADP-ribose) polymerase-1 (PARP-1), and PARP-1 in apoptotic cells is inactivated by caspase-mediated proteolysis. Consistently, we observed intact and cleaved forms of PARP-1 in nsPEF-exposed and UV-irradiated cells, respectively. Taken together, nsPEFs induce two distinct modes of cell death in a cell type-specific manner, and HeLa S3 cells show PAR-associated non-apoptotic cell death in response to nsPEFs.

Nanosecond pulsed electric fields induce poly(ADP-ribose) formation and non-apoptotic cell death in HeLa S3 cells

International Nuclear Information System (INIS)

Morotomi-Yano, Keiko; Akiyama, Hidenori; Yano, Ken-ichi

2013-01-01

Highlights: •Nanosecond pulsed electric field (nsPEF) is a new and unique means for life sciences. •Apoptosis was induced by nsPEF exposure in Jurkat cells. •No signs of apoptosis were detected in HeLa S3 cells exposed to nsPEFs. •Formation of poly(ADP-ribose) was induced in nsPEF-exposed HeLa S3 cells. •Two distinct modes of cell death were activated by nsPEF in a cell-dependent manner. -- Abstract: Nanosecond pulsed electric fields (nsPEFs) have recently gained attention as effective cancer therapy owing to their potency for cell death induction. Previous studies have shown that apoptosis is a predominant mode of nsPEF-induced cell death in several cell lines, such as Jurkat cells. In this study, we analyzed molecular mechanisms for cell death induced by nsPEFs. When nsPEFs were applied to Jurkat cells, apoptosis was readily induced. Next, we used HeLa S3 cells and analyzed apoptotic events. Contrary to our expectation, nsPEF-exposed HeLa S3 cells exhibited no molecular signs of apoptosis execution. Instead, nsPEFs induced the formation of poly(ADP-ribose) (PAR), a hallmark of necrosis. PAR formation occurred concurrently with a decrease in cell viability, supporting implications of nsPEF-induced PAR formation for cell death. Necrotic PAR formation is known to be catalyzed by poly(ADP-ribose) polymerase-1 (PARP-1), and PARP-1 in apoptotic cells is inactivated by caspase-mediated proteolysis. Consistently, we observed intact and cleaved forms of PARP-1 in nsPEF-exposed and UV-irradiated cells, respectively. Taken together, nsPEFs induce two distinct modes of cell death in a cell type-specific manner, and HeLa S3 cells show PAR-associated non-apoptotic cell death in response to nsPEFs

Caspase-10 Is the Key Initiator Caspase Involved in Tributyltin-Mediated Apoptosis in Human Immune Cells

Directory of Open Access Journals (Sweden)

Harald F. Krug

2012-01-01

Full Text Available Tributyltin (TBT is one of the most toxic compounds produced by man and distributed in the environment. A multitude of toxic activities have been described, for example, immunotoxic, neurotoxic, and endocrine disruptive effects. Moreover, it has been shown for many cell types that they undergo apoptosis after treatment with TBT and the cell death of immune cells could be the molecular background of its immunotoxic effect. As low as 200 nM up to 1 μM of TBT induces all signs of apoptosis in Jurkat T cells within 1 to 24 hrs of treatment. When compared to Fas-ligand control stimulation, the same sequence of events occurs: membrane blebbing, phosphatidylserine externalisation, the activation of the “death-inducing signalling complex,” and the following sequence of cleavage processes. In genetically modified caspase-8-deficient Jurkat cells, the apoptotic effects are only slightly reduced, whereas, in FADD-negative Jurkat cells, the TBT effect is significantly diminished. We could show that caspase-10 is recruited by the TRAIL-R2 receptor and apoptosis is totally prevented when caspase-10 is specifically inhibited in all three cell lines.

A role for protein kinase C in the regulation of membrane fluidity and Ca²(+) flux at the endoplasmic reticulum and plasma membranes of HEK293 and Jurkat cells.

Science.gov (United States)

Chen, Lihong; Meng, Qingli; Jing, Xian; Xu, Pingxiang; Luo, Dali

2011-02-01

Protein kinase C (PKC) plays a prominent role in the regulation of a variety of cellular functions, including Ca²(+) signalling. In HEK293 and Jurkat cells, the Ca²(+) release and Ca²(+) uptake stimulated by several different activators were attenuated by activation of PKC with phorbol myristate acetate (PMA) or 1-oleoyl-2-acetyl-sn-glycerol (OAG) and potentiated by PKC inhibition with Gö6983 or knockdown of PKCα or PKCβ using shRNA. Immunostaining and Western blotting analyses revealed that PKCα and PKCβII accumulated at the plasma membrane (PM) and that these isoforms, along with PKCβI, also translocated to the endoplasmic reticulum (ER) upon activation with PMA. Measurements of membrane fluidity showed that, like the cell membrane stabilizers bovine serum albumin (BSA) and ursodeoxycholate (UDCA), PMA and OAG significantly reduced the fluidity of both the PM and ER membranes; these effects were blocked in PKC-knockdown cells. Interestingly, both BSA and UDCA inhibited the Ca²(+) responses to agonists to the same extent as PMA, whereas Tween 20, which increases membrane fluidity, raised the internal Ca²(+) concentration. Thus, activation of PKC induces both translocation of PKC to the PM and ER membranes and downregulation of membrane fluidity, thereby negatively modulating Ca²(+) flux. Copyright © 2010 Elsevier Inc. All rights reserved.

Fraction against Human Cancer Cell Lines

African Journals Online (AJOL)

fraction of A. sieberi against seven cancer cell lines (Colo20, HCT116, DLD, MCF7, Jurkat, HepG2 and ... The morphology of the HepG2 cell nucleus was investigated by Hoechst 33342, ..... Gong F, Liang Y, Xie P, Chau F. Information theory.

Comparative effect of two pan-class I PI3K inhibitors used as anticancer drugs on human T cell function.

Science.gov (United States)

Blanco, Belén; Herrero-Sánchez, Carmen; Rodríguez-Serrano, Concepción; Sánchez-Barba, Mercedes; Del Cañizo, María Consuelo

2015-09-01

The phosphatidylinositol 3-kinase (PI3K) pathway is commonly deregulated in cancer and, thus, PI3K has been recognized as an attractive molecular target for novel anti-cancer therapies. However, the effect of PI3K inhibitors on T-cell function, a key component of antitumor immunity, has been scantly explored. The objective of this study was to investigate the effect on human T-cell activation of two PI3K inhibitors currently being tested in clinical trials: PX-866 and BKM120. Their activity against a leukemic T cell line was also assessed. For that purpose, Jurkat cells or anti-CD3/anti-CD28 stimulated human peripheral blood mononuclear cells were cultured in the presence of different concentrations of PX-866 or BKM120 and their effect on T-cell proliferation, apoptosis, expression of activation markers and cytokine secretion was analyzed by flow cytometry. In addition, Akt and Erk phosphorylation was analyzed by Western blotting. Both PX-866 and BKM120 decreased viability of Jurkat cells and blocked cell cycle progression. Regarding primary T cells, both compounds similarly inhibited expression of activation markers and cytokine secretion, although they did not induce apoptosis of stimulated T cells. Interestingly, we found differences in their ability to block T-cell proliferation and IL-2 secretion, exerting BKM120 a more potent inhibition. These disparate effects could be related to differences observed in PI3K/Akt and RAS/MEK/ERK signaling between PX-866 and BKM120 treated cells. Our results suggest that, when selecting a PI3K inhibitor for cancer therapy, immunosuppressive characteristics should be taken into account in order to minimize detrimental effects on immune function. Copyright © 2015 Elsevier B.V. All rights reserved.

Targeted Lymphoma Cell Death by Novel Signal Transduction Modifications

Science.gov (United States)

2011-07-01

60 80 100 120 Jurkat R am os R aji M C 116 D O H H 2 W S U -W M W S U -C LL K arpas 519 C ell Lines A s C o n tr o l ( % ) Figure 6...Lym phom a cell Lines 0 20 40 60 80 100 120 Jurkat R am os R aji M C 116 D O H H 2 W S U -W M W S U -C LL K arpas 519 C ell Lines A s C o n tr o l...plemented with 10% FCS and incubated with AET- activated sheep red blood cells (SRBC) for 1 h. B-cells were collected at the interface after centrifugation

Induction of galectin-1 expression by HTLV-I Tax and its impact on HTLV-I infectivity

Directory of Open Access Journals (Sweden)

Sato Sachiko

2008-11-01

Full Text Available Abstract Background Cell-free Human T-cell Leukemia Virus type I (HTLV-I virions are poorly infectious and cell-to-cell contact is often required to achieve infection. Other factors might thus importantly contribute in increasing infection by HTLV-I. Galectin-1 is a galactoside-binding lectin which is secreted by activated T lymphocytes. Several functions have been attributed to this protein including its capacity to increase cell-to-cell adhesion. Based on previous studies, we postulated that this protein could also accentuate HTLV-I infection. Results Herein, we demonstrate that galectin-1 expression and release are higher in HTLV-I-infected T cells in comparison to uninfected T cells. Furthermore, galectin-1 expression was activated in various cell lines expressing the wild type viral Tax protein while this induction was minimal upon expression of NF-κB activation-defective TaxM22. Cotransfection of these Tax expression vectors with galectin-1 promoter-driven luciferase constructs confirmed that Tax upregulated galectin-1 promoter activity. However, a NF-κB-independent mechanism was strongly favoured in this induction of galectin-1 expression as no activation of the promoter was apparent in Jurkat cells treated with known NF-κB activators. Using HTLV-I envelope pseudotyped HIV-1 virions, galectin-1 was shown to increase infectivity. In addition, a co-culture assay with HTLV-I-infected cells also indicated an increase in cell fusion upon addition of galectin-1. This effect was not mediated by factors present in the supernatant of the HTLV-I-infected cells. Conclusion These data suggest that HTLV-I Tax increases galectin-1 expression and that this modulation could play an important role in HTLV-I infection by stabilizing both cell-to-cell and virus-cell interactions.

Efecto de extractos de la esponja calcarea Leucetta aff. floridana sobre el ciclo de líneas celulares leucemoides Effect of extracts from the calcareous sponge Leucetta aff. floridana on the cell cycle of leukemoid cell lines

Directory of Open Access Journals (Sweden)

Diana Margarita Márquez Fernández

2012-12-01

.Introduction: Leucetta aff. floridana sponge produces compounds with differential antiproliferative activity on lung and breast cancer. Nevertheless, this activity in other tumour cell lines has not yet been tested and it remains unknown whether its antiproliferative potential is correlated with the cell progression through cell cycle or not. Objective: To evaluate the antiproliferative and anticlonogenic potential and the effect of methanolic and hexanic extracts of sponge L. aff. floridana from the Colombian Caribbean region on the cell cycle of Jurkat and K562 leukemoid cell lines. Methods: The viability and antiproliferative effect were determined using trypan blue assay at 0, 24, 48, 72 and 96 hours. Clongenicity and effect on cell cycle were assayed at 10 and 100 µg/mL Data obtained were analyzed using multifactorial ANOVA and Tukey's test. Results: The hexanic extract presented antiproliferative activity in both Jurkat and K652 cell lines; Jurkat being more sensitive than K652. These results were confirmed by clongenicity assays. The hexanic extract also showed its effect on the dose-dependent accumulation of Sub-G1 cells, although it was different in the two cell lines. The duration of the treatment with the hexanic extract was not significant for K562 cell line, but it was for Jurkat cells. Additionally, the percentage of cell accumulation in Sub-G1 was higher in K562 than in Jurkat cells. The methanolic extract showed antiproliferative effect similar to that of the hexanic extract, but more potent at the lowest concentration (10 µg/mL in K652 cell line clonegenicity. The effect on cell cycle was also similar to that of the hexanic extract, but in this case the duration of treatment was not significant in the cell accumulation in Sub-G1. Conclusions: Altogether these results show the differential potential of the extracts on the cell cycle of the evaluated leukemoid cell lines.

Aberrant methylation of the M-type phospholipase A2 receptor gene in leukemic cells

International Nuclear Information System (INIS)

Menschikowski, Mario; Platzbecker, Uwe; Hagelgans, Albert; Vogel, Margot; Thiede, Christian; Schönefeldt, Claudia; Lehnert, Renate; Eisenhofer, Graeme; Siegert, Gabriele

2012-01-01

The M-type phospholipase A2 receptor (PLA2R1) plays a crucial role in several signaling pathways and may act as tumor-suppressor. This study examined the expression and methylation of the PLA2R1 gene in Jurkat and U937 leukemic cell lines and its methylation in patients with myelodysplastic syndrome (MDS) or acute leukemia. Sites of methylation of the PLA2R1 locus were identified by sequencing bisulfite-modified DNA fragments. Methylation specific-high resolution melting (MS-HRM) analysis was then carried out to quantify PLA2R1 methylation at 5-CpG sites identified with differences in methylation between healthy control subjects and leukemic patients using sequencing of bisulfite-modified genomic DNA. Expression of PLA2R1 was found to be completely down-regulated in Jurkat and U937 cells, accompanied by complete methylation of PLA2R1 promoter and down-stream regions; PLA2R1 was re-expressed after exposure of cells to 5-aza-2´-deoxycytidine. MS-HRM analysis of the PLA2R1 locus in patients with different types of leukemia indicated an average methylation of 28.9% ± 17.8%, compared to less than 9% in control subjects. In MDS patients the extent of PLA2R1 methylation significantly increased with disease risk. Furthermore, measurements of PLA2R1 methylation appeared useful for predicting responsiveness to the methyltransferase inhibitor, azacitidine, as a pre-emptive treatment to avoid hematological relapse in patients with high-risk MDS or acute myeloid leukemia. The study shows for the first time that PLA2R1 gene sequences are a target of hypermethylation in leukemia, which may have pathophysiological relevance for disease evolution in MDS and leukemogenesis

MHC class I is functionally associated with antigen receptors in human T and B lymphomas

DEFF Research Database (Denmark)

Pedersen, Anders Elm; Jacoby, B F; Skov, S

1996-01-01

lines the increase in [Ca2+]i after MHC-I cross-linking caused upregulation of CD69, an early marker of activation. When studying the effect of MHC-I cross-linking on the TCR- and B cell antigen receptor (BCR)- mediated increase in [Ca2+]i, respectively, we observed that MHC-I had a costimulatory effect...... on the TCR-mediated increase in [Ca2+]i in Jurkat cells but not on the anti-IgM-mediated activity of Solubo cells. Studies of subpopulations of Jurkat and Solubo cells expressing different levels of MHC-I on their cell surfaces revealed that the TCR- and BCR-mediated increases in [Ca2+]i, respectively, were...

NF45/ILF2 tissue expression, promoter analysis, and interleukin-2 transactivating function

International Nuclear Information System (INIS)

Zhao Guohua; Shi Lingfang; Qiu Daoming; Hu Hong; Kao, Peter N.

2005-01-01

NF45/ILF2 associates with NF90/ILF3 in the nucleus and regulates IL-2 gene transcription at the antigen receptor response element (ARRE)/NF-AT DNA target sequence (P.N. Kao, L. Chen, G. Brock, J. Ng, A.J. Smith, B. Corthesy, J. Biol. Chem. 269 (1994) 20691-20699). NF45 is widely expressed in normal tissues, especially testis, brain, and kidney, with a predominantly nuclear distribution. NF45 mRNA expression is increased in lymphoma and leukemia cell lines. The human and murine NF45 proteins differ only by substitution of valine by isoleucine at amino acid 142. Fluorescence in situ hybridization localized the human NF45 gene to chromosome 1q21.3, and mouse NF45 gene to chromosome 3F1. Promoter analysis of 2.5 kB of the murine NF45 gene reveals that significant activation is conferred by factors, possible including NF-Y, that bind to the CCAAT-box sequence. The function of human NF45 in regulating IL-2 gene expression was characterized in Jurkat T-cells stably transfected with plasmids directing expression of NF45 cDNA in sense or antisense orientations. NF45 sense expression increased IL-2 luciferase reporter gene activity 120-fold, and IL-2 protein expression 2-fold compared to control cells. NF45 is a highly conserved, regulated transcriptional activator, and one target gene is IL-2

Modulation of ceramide metabolism in T-leukemia cell lines potentiates apoptosis induced by the cationic antimicrobial peptide bovine lactoferricin.

Science.gov (United States)

Furlong, Suzanne J; Ridgway, Neale D; Hoskin, David W

2008-03-01

Bovine lactoferricin (LfcinB) is a cationic antimicrobial peptide that selectively induces apoptosis in several different types of human cancer cells. However, the potential use of LfcinB as an anticancer agent is presently limited by the need for relatively high concentrations of the peptide to trigger apoptosis. Ceramide is a membrane sphingolipid that is believed to function as a second messenger during apoptosis. In this study, we investigated the role of ceramide in LfcinB-induced apoptosis in CCRF-CEM and Jurkat T-leukemia cell lines. Exposure to LfcinB caused nuclear condensation and fragmentation, poly(ADP-ribose) polymerase (PARP) cleavage, and DNA fragmentation in CCRF-CEM and Jurkat T-cell acute lymphoblastic leukemia cell lines. Treatment with C6 ceramide, a cell-permeable, short-chain ceramide analog, also induced apoptotic nuclear morphology, PARP cleavage, and DNA fragmentation in T-leukemia cells. Although LfcinB treatment did not cause ceramide to accumulate in CCRF-CEM or Jurkat cells, the addition of C6 ceramide to LfcinB-treated T-leukemia cells resulted in increased DNA fragmentation. Furthermore, modulation of cellular ceramide metabolism either by inhibiting ceramidases with D-erythro-2-(N-myristoylamino)-1-phenyl-1-propanol or N-oleoylethanolamine, or by blocking glucosylceramide synthase activity with 1-phenyl-2-palmitoylamino-3-morpholino-1-propanol, enhanced the ability of LfcinB to trigger apoptosis in both Jurkat and CCRF-CEM cells. In addition, LfcinB-induced apoptosis of T-leukemia cells was enhanced in the presence of the antiestrogen tamoxifen, which has multiple effects on cancer cells, including inhibition of glucosylceramide synthase activity. We conclude that manipulation of cellular ceramide levels in combination with LfcinB therapy warrants further investigation as a novel strategy for the treatment of T cell-derived leukemias.

Recombinant carcinoembryonic antigen as a reporter gene for molecular imaging

International Nuclear Information System (INIS)

Kenanova, Vania; Barat, Bhaswati; Olafsen, Tove; Chatziioannou, Arion; Herschman, Harvey R.; Wu, Anna M.; Braun, Jonathan

2009-01-01

Reporter genes can provide a way of noninvasively assessing gene activity in vivo. However, current reporter gene strategies may be limited by the immunogenicity of foreign reporter proteins, endogenous expression, or unwanted biological activity. We have developed a reporter gene based on carcinoembryonic antigen (CEA), a human protein with limited normal tissue expression. To construct a CEA reporter gene for PET, a CEA minigene (N-A3) was fused to the extracellular and transmembrane domains of the human FcγRIIb receptor. The NA3-FcγRIIb recombinant gene, driven by a CMV promoter, was transfected in Jurkat (human T cell leukemia) cells. Expression was analyzed by flow cytometry, immunohistochemistry (IHC), and microPET imaging. Flow cytometry identified Jurkat clones stably expressing NA3-FcγRIIb at low, medium, and high levels. High and medium NA3-FcγRIIb expression could also be detected by Western blot. Reporter gene positive and negative Jurkat cells were used to establish xenografts in athymic mice. IHC showed staining of the tumor with high reporter gene expression; medium and low N-A3 expression was not detected. MicroPET imaging, using an anti-CEA 124 I-labeled single-chain Fv-Fc antibody fragment, demonstrated that only high N-A3 expression could be detected. Specific accumulation of activity was visualized at the N-A3 positive tumor as early as 4 h. MicroPET image quantitation showed tumor activity of 1.8 ± 0.2, 15.2 ± 1.3, and 4.6 ± 1.2 percent injected dose per gram (%ID/g) at 4, 20, and 48 h, respectively. Biodistribution at 48 h demonstrated tumor uptake of 4.8 ± 0.8%ID/g. The CEA N-A3 minigene has the potential to be used as a reporter gene for imaging cells in vivo. (orig.)

Effect of low-dose irradiation on expression of mRNA and protein. Pt.1. Induction of thioredoxin as radioprotective protein in human lymphocytes

International Nuclear Information System (INIS)

Hoshi, Yuko; Tanooka, Hiroshi; Wakasugi, Hiro; Miyasaki, Kunihisa

1997-01-01

To elucidate the mechanism of hormetic effect by low-dose ionizing radiation, we studied the expression of the thioredoxin (TRX) gene in human lymphocytes after irradiation. TRX is a radioprotector and a key protein regulating cellular functions through redox reaction. The major results obtained were as follows; (1) The peaks of TRX mRNA expression and protein synthesis in human lymphocytes appeared 6-8 hr after irradiation with 25cGy. (2) At 6 hr after irradiation, the optimum dose for induction of TRX mRNA and TRX protein in human lymphocytes appeared to be 25-50cGy. (3) Induction of expression TRX mRNA had individual variations about twice. (4) Lymphocytes prepared from fresh venous blood showed the lowest TRX mRNA level in other cells such a Jurkat cells, lymphocytes stimulated for now with IL-2 and CD3 and the immortalized cell line 1G8. (5) The optimal dose and time course of induction of TRX by low-dose radiation suggest that TRX is related to the radio-adaptive response. (author)

Eurycomanone and Eurycomanol from Eurycoma longifolia Jack as Regulators of Signaling Pathways Involved in Proliferation, Cell Death and Inflammation

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Shéhérazade Hajjouli

2014-09-01

Full Text Available Eurycomanone and eurycomanol are two quassinoids from the roots of Eurycoma longifolia Jack. The aim of this study was to assess the bioactivity of these compounds in Jurkat and K562 human leukemia cell models compared to peripheral blood mononuclear cells from healthy donors. Both eurycomanone and eurycomanol inhibited Jurkat and K562 cell viability and proliferation without affecting healthy cells. Interestingly, eurycomanone inhibited NF-κB signaling through inhibition of IκBα phosphorylation and upstream mitogen activated protein kinase (MAPK signaling, but not eurycomanol. In conclusion, both quassinoids present differential toxicity towards leukemia cells, and the presence of the α,β-unsaturated ketone in eurycomanone could be prerequisite for the NF-κB inhibition.

DNA-barcode directed capture and electrochemical metabolic analysis of single mammalian cells on a microelectrode array.

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Douglas, Erik S; Hsiao, Sonny C; Onoe, Hiroaki; Bertozzi, Carolyn R; Francis, Matthew B; Mathies, Richard A

2009-07-21

A microdevice is developed for DNA-barcode directed capture of single cells on an array of pH-sensitive microelectrodes for metabolic analysis. Cells are modified with membrane-bound single-stranded DNA, and specific single-cell capture is directed by the complementary strand bound in the sensor area of the iridium oxide pH microelectrodes within a microfluidic channel. This bifunctional microelectrode array is demonstrated for the pH monitoring and differentiation of primary T cells and Jurkat T lymphoma cells. Single Jurkat cells exhibited an extracellular acidification rate of 11 milli-pH min(-1), while primary T cells exhibited only 2 milli-pH min(-1). This system can be used to capture non-adherent cells specifically and to discriminate between visually similar healthy and cancerous cells in a heterogeneous ensemble based on their altered metabolic properties.

Synthesis of Scutellarein Derivatives with a Long Aliphatic Chain and Their Biological Evaluation against Human Cancer Cells

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Guanghui Ni

2018-02-01

Full Text Available Scutellarin is the major active flavonoid extracted from the traditional Chinese herbal medicine Erigeron breviscapus (Vant. Hand-Mazz., which is widely used in China. Recently, accumulating evidence has highlighted the potential role of scutellarin and its main metabolite scutellarein in the treatment of cancer. To explore novel anticancer agents with high efficiency, a series of new scutellarein derivatives with a long aliphatic chain were synthesized, and the antiproliferative activities against Jurkat, HCT-116 and MDA-MB-231 cancer cell lines were assessed. Among them, compound 6a exhibited the strongest antiproliferative effects on Jurkat (IC50 = 1.80 μM, HCT-116 (IC50 = 11.50 μM and MDA-MB-231 (IC50 = 53.91 μM. In particular, 6a even showed stronger antiproliferative effects than the positive control NaAsO2 on Jurkat and HCT-116 cell lines. The results showed that a proper long aliphatic chain enhanced the antiproliferative activity of scutellarein.

Synthesis of Scutellarein Derivatives with a Long Aliphatic Chain and Their Biological Evaluation against Human Cancer Cells.

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Ni, Guanghui; Tang, Yanling; Li, Minxin; He, Yuefeng; Rao, Gaoxiong

2018-02-01

Scutellarin is the major active flavonoid extracted from the traditional Chinese herbal medicine Erigeron breviscapus (Vant.) Hand-Mazz., which is widely used in China. Recently, accumulating evidence has highlighted the potential role of scutellarin and its main metabolite scutellarein in the treatment of cancer. To explore novel anticancer agents with high efficiency, a series of new scutellarein derivatives with a long aliphatic chain were synthesized, and the antiproliferative activities against Jurkat, HCT-116 and MDA-MB-231 cancer cell lines were assessed. Among them, compound 6a exhibited the strongest antiproliferative effects on Jurkat (IC 50 = 1.80 μM), HCT-116 (IC 50 = 11.50 μM) and MDA-MB-231 (IC 50 = 53.91 μM). In particular, 6a even showed stronger antiproliferative effects than the positive control NaAsO₂ on Jurkat and HCT-116 cell lines. The results showed that a proper long aliphatic chain enhanced the antiproliferative activity of scutellarein.

Ligation of major histocompatibility complex class I antigens (MHC-I) prevents apoptosis induced by Fas or SAPK/JNK activation in T-lymphoma cells

DEFF Research Database (Denmark)

Lamberth, K; Claesson, M H

2001-01-01

Early apoptosis in Jurkat T-lymphoma cells was induced by agonistic anti-Fas Ab or by anisomycin which activates the stress kinases SAPK/JNK. Apoptosis was inhibited by ligation of major histocompatibility complex class I antigens (MHC-I). MHC-I ligation induced upregulation of the anti-apoptotic......Early apoptosis in Jurkat T-lymphoma cells was induced by agonistic anti-Fas Ab or by anisomycin which activates the stress kinases SAPK/JNK. Apoptosis was inhibited by ligation of major histocompatibility complex class I antigens (MHC-I). MHC-I ligation induced upregulation of the anti......-apoptotic Bcl-2 protein and stabilized the mitochondrial membrane potential (Deltapsim). MHC-I ligation also prevented downregulation of Bcl-2 and destabilization of Deltapsim induced by anti-Fas Ab treatment or anisomycin exposure. Studies on three different Jurkat cell mutants deficient for src p56(lck), ZAP......-70 kinase, or TCR/CD3 gamma-chain showed that the cells undergo apoptosis after Fas ligation. Anisomycin exposure induced apoptosis in the src p56(lck)-deficient cell line but not in the two other mutant cell lines. Simultaneous cross-linking of MHC-I and Fas ligation inhibited apoptosis in the ZAP...

Alterations in the nuclear proteome of HIV-1 infected T-cells

International Nuclear Information System (INIS)

DeBoer, Jason; Jagadish, Teena; Haverland, Nicole A.; Madson, Christian J.; Ciborowski, Pawel; Belshan, Michael

2014-01-01

Virus infection of a cell involves the appropriation of host factors and the innate defensive response of the cell. The identification of proteins critical for virus replication may lead to the development of novel, cell-based inhibitors. In this study we mapped the changes in T-cell nuclei during human immunodeficiency virus type 1 (HIV-1) at 20 hpi. Using a stringent data threshold, a total of 13 and 38 unique proteins were identified in infected and uninfected cells, respectively, across all biological replicates. An additional 15 proteins were found to be differentially regulated between infected and control nuclei. STRING analysis identified four clusters of protein–protein interactions in the data set related to nuclear architecture, RNA regulation, cell division, and cell homeostasis. Immunoblot analysis confirmed the differential expression of several proteins in both C8166-45 and Jurkat E6-1 T-cells. These data provide a map of the response in host cell nuclei upon HIV-1 infection. - Highlights: • We identify changes in the expression of nuclear proteins during HIV-1 infection. • 163 nuclear proteins were found differentially regulated during HIV-1 infection. • Bioinformatic analysis identified several nuclear pathways altered by HIV infection. • Candidate factors were validated in two independent cell lines

Alterations in the nuclear proteome of HIV-1 infected T-cells

Energy Technology Data Exchange (ETDEWEB)

DeBoer, Jason [Department of Medical Microbiology and Immunology, Creighton University, 2500 California Plaza, Omaha, NE 68178 (United States); Jagadish, Teena; Haverland, Nicole A. [Department of Pharmacology and Experimental Neuroscience, University of Nebraska Medical Center, Omaha, NE 68198 (United States); Madson, Christian J. [Department of Medical Microbiology and Immunology, Creighton University, 2500 California Plaza, Omaha, NE 68178 (United States); Ciborowski, Pawel [Department of Pharmacology and Experimental Neuroscience, University of Nebraska Medical Center, Omaha, NE 68198 (United States); The Nebraska Center for Virology, University of Nebraska, Lincoln 68583 (United States); Belshan, Michael, E-mail: michaelbelshan@creighton.edu [Department of Medical Microbiology and Immunology, Creighton University, 2500 California Plaza, Omaha, NE 68178 (United States); The Nebraska Center for Virology, University of Nebraska, Lincoln 68583 (United States)

2014-11-15

Virus infection of a cell involves the appropriation of host factors and the innate defensive response of the cell. The identification of proteins critical for virus replication may lead to the development of novel, cell-based inhibitors. In this study we mapped the changes in T-cell nuclei during human immunodeficiency virus type 1 (HIV-1) at 20 hpi. Using a stringent data threshold, a total of 13 and 38 unique proteins were identified in infected and uninfected cells, respectively, across all biological replicates. An additional 15 proteins were found to be differentially regulated between infected and control nuclei. STRING analysis identified four clusters of protein–protein interactions in the data set related to nuclear architecture, RNA regulation, cell division, and cell homeostasis. Immunoblot analysis confirmed the differential expression of several proteins in both C8166-45 and Jurkat E6-1 T-cells. These data provide a map of the response in host cell nuclei upon HIV-1 infection. - Highlights: • We identify changes in the expression of nuclear proteins during HIV-1 infection. • 163 nuclear proteins were found differentially regulated during HIV-1 infection. • Bioinformatic analysis identified several nuclear pathways altered by HIV infection. • Candidate factors were validated in two independent cell lines.

Rapid alterations of cell cycle control proteins in human T lymphocytes in microgravity

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Thiel Cora S

2012-01-01

Full Text Available Abstract In our study we aimed to identify rapidly reacting gravity-responsive mechanisms in mammalian cells in order to understand if and how altered gravity is translated into a cellular response. In a combination of experiments using "functional weightlessness" provided by 2D-clinostats and real microgravity provided by several parabolic flight campaigns and compared to in-flight-1g-controls, we identified rapid gravity-responsive reactions inside the cell cycle regulatory machinery of human T lymphocytes. In response to 2D clinorotation, we detected an enhanced expression of p21 Waf1/Cip1 protein within minutes, less cdc25C protein expression and enhanced Ser147-phosphorylation of cyclinB1 after CD3/CD28 stimulation. Additionally, during 2D clinorotation, Tyr-15-phosphorylation occurred later and was shorter than in the 1 g controls. In CD3/CD28-stimulated primary human T cells, mRNA expression of the cell cycle arrest protein p21 increased 4.1-fold after 20s real microgravity in primary CD4+ T cells and 2.9-fold in Jurkat T cells, compared to 1 g in-flight controls after CD3/CD28 stimulation. The histone acetyltransferase (HAT inhibitor curcumin was able to abrogate microgravity-induced p21 mRNA expression, whereas expression was enhanced by a histone deacetylase (HDAC inhibitor. Therefore, we suppose that cell cycle progression in human T lymphocytes requires Earth gravity and that the disturbed expression of cell cycle regulatory proteins could contribute to the breakdown of the human immune system in space.

Cloning and Functional Analysis of cDNAs with Open Reading Frames for 300 Previously Undefined Genes Expressed in CD34+ Hematopoietic Stem/Progenitor Cells

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Zhang, Qing-Hua; Ye, Min; Wu, Xin-Yan; Ren, Shuang-Xi; Zhao, Meng; Zhao, Chun-Jun; Fu, Gang; Shen, Yu; Fan, Hui-Yong; Lu, Gang; Zhong, Ming; Xu, Xiang-Ru; Han, Ze-Guang; Zhang, Ji-Wang; Tao, Jiong; Huang, Qiu-Hua; Zhou, Jun; Hu, Geng-Xi; Gu, Jian; Chen, Sai-Juan; Chen, Zhu

2000-01-01

Three hundred cDNAs containing putatively entire open reading frames (ORFs) for previously undefined genes were obtained from CD34+ hematopoietic stem/progenitor cells (HSPCs), based on EST cataloging, clone sequencing, in silico cloning, and rapid amplification of cDNA ends (RACE). The cDNA sizes ranged from 360 to 3496 bp and their ORFs coded for peptides of 58–752 amino acids. Public database search indicated that 225 cDNAs exhibited sequence similarities to genes identified across a variety of species. Homology analysis led to the recognition of 50 basic structural motifs/domains among these cDNAs. Genomic exon–intron organization could be established in 243 genes by integration of cDNA data with genome sequence information. Interestingly, a new gene named as HSPC070 on 3p was found to share a sequence of 105bp in 3′ UTR with RAF gene in reversed transcription orientation. Chromosomal localizations were obtained using electronic mapping for 192 genes and with radiation hybrid (RH) for 38 genes. Macroarray technique was applied to screen the gene expression patterns in five hematopoietic cell lines (NB4, HL60, U937, K562, and Jurkat) and a number of genes with differential expression were found. The resource work has provided a wide range of information useful not only for expression genomics and annotation of genomic DNA sequence, but also for further research on the function of genes involved in hematopoietic development and differentiation. [The sequence data described in this paper have been submitted to the GenBank data library under the accession nos. listed in Table 1, pp 1548–1552.] PMID:11042152

Use of short interfering RNA delivered by cationic liposomes to enable efficient down-regulation of PTPN22 gene in human T lymphocytes.

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Valentina Perri

Full Text Available Type 1 diabetes and thyroid disease are T cell-dependent autoimmune endocrinopathies. The standard substitutive administration of the deficient hormones does not halt the autoimmune process; therefore, development of immunotherapies aiming to preserve the residual hormonal cells, is of crucial importance. PTPN22 C1858T mutation encoding for the R620W lymphoid tyrosine phosphatase variant, plays a potential pathophysiological role in autoimmunity. The PTPN22 encoded protein Lyp is a negative regulator of T cell antigen receptor signaling; R620W variant, leading to a gain of function with paradoxical reduced T cell activation, may represent a valid therapeutic target. We aimed to develop novel wild type PTPN22 short interfering RNA duplexes (siRNA and optimize their delivery into Jurkat T cells and PBMC by using liposomal carriers. Conformational stability, size and polydispersion of siRNA in lipoplexes was measured by CD spectroscopy and DLS. Lipoplexes internalization and toxicity evaluation was assessed by confocal microscopy and flow cytometry analysis. Their effect on Lyp expression was evaluated by means of Western Blot and confocal microscopy. Functional assays through engagement of TCR signaling were established to evaluate biological consequences of down-modulation. Both Jurkat T cells and PBMC were efficiently transfected by stable custom lipoplexes. Jurkat T cell morphology and proliferation was not affected. Lipoplexes incorporation was visualized in CD3+ but also in CD3- peripheral blood immunotypes without signs of toxicity, damage or apoptosis. Efficacy in affecting Lyp protein expression was demonstrated in both transfected Jurkat T cells and PBMC. Moreover, impairment of Lyp inhibitory activity was revealed by increase of IL-2 secretion in culture supernatants of PBMC following anti-CD3/CD28 T cell receptor-driven stimulation. The results of our study open the pathway to future trials for the treatment of autoimmune diseases based

Curcumin induces apoptotic cell death of activated human CD4+ T cells via increasing endoplasmic reticulum stress and mitochondrial dysfunction.

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Zheng, Min; Zhang, Qinggao; Joe, Yeonsoo; Lee, Bong Hee; Ryu, Do Gon; Kwon, Kang Beom; Ryter, Stefan W; Chung, Hun Taeg

2013-03-01

Curcumin, a natural polyphenolic antioxidant compound, exerts well-known anti-inflammatory and immunomodulatory effects, the latter which can influence the activation of immune cells including T cells. Furthermore, curcumin can inhibit the expression of pro-inflammatory cytokines and chemokines, through suppression of the NF-κB signaling pathway. The beneficial effects of curcumin in diseases such as arthritis, allergy, asthma, atherosclerosis, diabetes and cancer may be due to its immunomodulatory properties. We studied the potential of curcumin to modulate CD4+ T cells-mediated autoimmune disease, by examining the effects of this compound on human CD4+ lymphocyte activation. Stimulation of human T cells with PHA or CD3/CD28 induced IL-2 mRNA expression and activated the endoplasmic reticulum (ER) stress response. The treatment of T cells with curcumin induced the unfolded protein response (UPR) signaling pathway, initiated by the phosphorylation of PERK and IRE1. Furthermore, curcumin increased the expression of the ER stress associated transcriptional factors XBP-1, cleaved p50ATF6α and C/EBP homologous protein (CHOP) in human CD4+ and Jurkat T cells. In PHA-activated T cells, curcumin further enhanced PHA-induced CHOP expression and reduced the expression of the anti-apoptotic protein Bcl-2. Finally, curcumin treatment induced apoptotic cell death in activated T cells via eliciting an excessive ER stress response, which was reversed by the ER-stress inhibitor 4-phenylbutyric acid or transfection with CHOP-specific siRNA. These results suggest that curcumin can impact both ER stress and mitochondria functional pathways, and thereby could be used as a promising therapy in the context of Th1-mediated autoimmune diseases. Copyright © 2013 Elsevier B.V. All rights reserved.

Expression of heparanase in basal cell carcinoma and squamous cell carcinoma.

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Pinhal, Maria Aparecida Silva; Almeida, Maria Carolina Leal; Costa, Alessandra Scorse; Theodoro, Thérèse Rachell; Serrano, Rodrigo Lorenzetti; Machado, Carlos D'Apparecida Santos

2016-01-01

Heparanase is an enzyme that cleaves heparan sulfate chains. Oligosaccharides generated by heparanase induce tumor progression. Basal cell carcinoma and squamous cell carcinoma comprise types of nonmelanoma skin cancer. Evaluate the glycosaminoglycans profile and expression of heparanase in two human cell lines established in culture, immortalized skin keratinocyte (HaCaT) and squamous cell carcinoma (A431) and also investigate the expression of heparanase in basal cell carcinoma, squamous cell carcinoma and eyelid skin of individuals not affected by the disease (control). Glycosaminoglycans were quantified by electrophoresis and indirect ELISA method. The heparanase expression was analyzed by quantitative RT-PCR (qRTPCR). The A431 strain showed significant increase in the sulfated glycosaminoglycans, increased heparanase expression and decreased hyaluronic acid, comparing to the HaCaT lineage. The mRNA expression of heparanase was significantly higher in Basal cell carcinoma and squamous cell carcinoma compared with control skin samples. It was also observed increased heparanase expression in squamous cell carcinoma compared to the Basal cell carcinoma. The glycosaminoglycans profile, as well as heparanase expression are different between HaCaT and A431 cell lines. The increased expression of heparanase in Basal cell carcinoma and squamous cell carcinoma suggests that this enzyme could be a marker for the diagnosis of such types of non-melanoma cancers, and may be useful as a target molecule for future alternative treatment.

Regulation of Gene Expression with Double-Stranded Phosphorothioate Oligonucleotides

Science.gov (United States)

Bielinska, Anna; Shivdasani, Ramesh A.; Zhang, Liquan; Nabel, Gary J.

1990-11-01

Alteration of gene transcription by inhibition of specific transcriptional regulatory proteins is necessary for determining how these factors participate in cellular differentiation. The functions of these proteins can be antagonized by several methods, each with specific limitations. Inhibition of sequence-specific DNA-binding proteins was achieved with double-stranded (ds) phosphorothioate oligonucleotides that contained octamer or kappaB consensus sequences. The phosphorothioate oligonucleotides specifically bound either octamer transcription factor or nuclear factor (NF)-kappaB. The modified oligonucleotides accumulated in cells more effectively than standard ds oligonucleotides and modulated gene expression in a specific manner. Octamer-dependent activation of a reporter plasmid or NF-kappaB-dependent activation of the human immunodeficiency virus (HIV) enhancer was inhibited when the appropriate phosphorothioate oligonucleotide was added to a transiently transfected B cell line. Addition of phosphorothioate oligonucleotides that contained the octamer consensus to Jurkat T leukemia cells inhibited interleukin-2 (IL-2) secretion to a degree similar to that observed with a mutated octamer site in the IL-2 enhancer. The ds phosphorothioate oligonucleotides probably compete for binding of specific transcription factors and may provide anti-viral, immunosuppressive, or other therapeutic effects.

Nanosecond pulsed electric fields induce poly(ADP-ribose) formation and non-apoptotic cell death in HeLa S3 cells.

Science.gov (United States)

Morotomi-Yano, Keiko; Akiyama, Hidenori; Yano, Ken-ichi

2013-08-30

Nanosecond pulsed electric fields (nsPEFs) have recently gained attention as effective cancer therapy owing to their potency for cell death induction. Previous studies have shown that apoptosis is a predominant mode of nsPEF-induced cell death in several cell lines, such as Jurkat cells. In this study, we analyzed molecular mechanisms for cell death induced by nsPEFs. When nsPEFs were applied to Jurkat cells, apoptosis was readily induced. Next, we used HeLa S3 cells and analyzed apoptotic events. Contrary to our expectation, nsPEF-exposed HeLa S3 cells exhibited no molecular signs of apoptosis execution. Instead, nsPEFs induced the formation of poly(ADP-ribose) (PAR), a hallmark of necrosis. PAR formation occurred concurrently with a decrease in cell viability, supporting implications of nsPEF-induced PAR formation for cell death. Necrotic PAR formation is known to be catalyzed by poly(ADP-ribose) polymerase-1 (PARP-1), and PARP-1 in apoptotic cells is inactivated by caspase-mediated proteolysis. Consistently, we observed intact and cleaved forms of PARP-1 in nsPEF-exposed and UV-irradiated cells, respectively. Taken together, nsPEFs induce two distinct modes of cell death in a cell type-specific manner, and HeLa S3 cells show PAR-associated non-apoptotic cell death in response to nsPEFs. Copyright © 2013 Elsevier Inc. All rights reserved.

Construction and Characterization of Insect Cell-Derived Influenza VLP: Cell Binding, Fusion, and EGFP Incorporation

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Yi-Shin Pan

2010-01-01

Full Text Available We have constructed virus-like particles (VLPs harboring hemagglutinin (HA, neuraminidase (NA, matrix protein 1 (M1 ,and proton channel protein (M2 using baculovirus as a vector in the SF9 insect cell. The size of the expressed VLP was estimated to be ~100 nm by light scattering experiment and transmission electron microscopy. Recognition of HA on the VLP surface by the HA2-specific monoclonal antibody IIF4 at acidic pH, as probed by surface plasmon resonance, indicated the pH-induced structural rearrangement of HA. Uptake of the particle by A549 mediated by HA-sialylose receptor interaction was visualized by the fluorescent-labeled VLP. The HA-promoted cell-virus fusion activity was illustrated by fluorescence imaging on the Jurkat cells incubated with rhodamine-loaded VLP performed at fusogenic pH. Furthermore, the green fluorescence protein (GFP was fused to NA to produce VLP with a pH-sensitive probe, expanding the use of VLP as an antigen carrier and a tool for viral tracking.

High level of Bcl-2 counteracts apoptosis mediated by a live rabies virus vaccine strain and induces long-term infection

International Nuclear Information System (INIS)

Thoulouze, Maria-Isabel; Lafage, Mireille; Yuste, Victor J.; Baloul, Leiela; Edelman, Lena; Kroemer, Guido; Israel, Nicole; Susin, Santos A.; Lafon, Monique

2003-01-01

We report here that rabies virus strains, currently used to immunize wildlife against rabies, induce not only caspase-dependent apoptosis in the human lymphoblastoid Jurkat T cell line (Jurkat-vect), but also a caspase-independent pathway involving the apoptosis-inducing factor (AIF). In contrast, a strain of neurotropic RV that does not induce apoptosis did not activate caspases or induce AIF translocation. Bcl-2 overproduction in Jurkat T cells (Jurkat-Bcl-2) abolished both pathways. ERA infection and production were similar in Jurkat-vect and Jurkat-Bcl-2 cells, indicating Bcl-2 has no direct antiviral effects. Bcl-2 production is naturally upregulated by day 3 in ERA-infected Jurkat-vect cultures. The increase in Bcl-2 levels seems to be controlled by the virus infection itself and results in the establishment of long-term, persistently infected cultures that continue to produce virus. Thus, in infections with live RV vaccine strains, infected cells may be productive reservoirs of virus in the long term. This may account for the high efficacy of live rabies vaccines

A full scale comparative study of methods for generation of functional Dendritic cells for use as cancer vaccines

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Kvalheim Gunnar

2007-07-01

Full Text Available Background Dendritic cells (DCs are professional antigen-presenting cells with the ability to induce primary T-cell responses and are commonly produced by culturing monocytes in the presence of IL-4 and GM-CSF for 5–7 days (Standard DC. Recently, Dauer and co-workers presented a modified protocol for differentiation of human monocytes into mature DCs within 48 hours (Fast DC. Here we report a functional comparison of the two strategies for generation of DCs from human monocytes with adaptions for large-scale clinical use. Methods The Elutra Cell Selection System was used to isolate monocytes after collection of leukapheresis product. The enriched monocytes were cultured in gas permeable Teflon bags with IL-4 and GM-CSF for 24 hours (Fast DC or 5 days (Standard DC to obtain immature DCs. The cells were then transfected with mRNA from the leukemia cell line Jurkat E6 by electroporation and incubated for additional 24 h or 2 days in the presence of pro-inflammatory cytokines (TNFα, IL-1β, IL-6 and PGE2 to obtain mature DCs. Results Mature Fast DC and Standard DC displayed comparable levels of many markers expressed on DC, including HLA-DR, CD83, CD86, CD208 and CCR7. However, compared to Standard DC, mature Fast DC was CD14high CD209low. Fast DC and Standard DC transfected with Jurkat E6-cell mRNA were equally able to elicit T cell specifically recognizing transfected DCs in vitro. IFNγ-secreting T cells were observed in both the CD4+ and CD8+ subsets. Conclusion Our results indicate that mature Fast DC are functional antigen presenting cells (APCs capable of inducing primary T-cell responses, and suggest that these cells may be valuable for generation of anti-tumor vaccines.

A full scale comparative study of methods for generation of functional Dendritic cells for use as cancer vaccines.

Science.gov (United States)

Jarnjak-Jankovic, Silvija; Hammerstad, Hege; Saebøe-Larssen, Stein; Kvalheim, Gunnar; Gaudernack, Gustav

2007-07-03

Dendritic cells (DCs) are professional antigen-presenting cells with the ability to induce primary T-cell responses and are commonly produced by culturing monocytes in the presence of IL-4 and GM-CSF for 5-7 days (Standard DC). Recently, Dauer and co-workers presented a modified protocol for differentiation of human monocytes into mature DCs within 48 hours (Fast DC). Here we report a functional comparison of the two strategies for generation of DCs from human monocytes with adaptions for large-scale clinical use. The Elutra Cell Selection System was used to isolate monocytes after collection of leukapheresis product. The enriched monocytes were cultured in gas permeable Teflon bags with IL-4 and GM-CSF for 24 hours (Fast DC) or 5 days (Standard DC) to obtain immature DCs. The cells were then transfected with mRNA from the leukemia cell line Jurkat E6 by electroporation and incubated for additional 24 h or 2 days in the presence of pro-inflammatory cytokines (TNFalpha, IL-1beta, IL-6 and PGE2) to obtain mature DCs. Mature Fast DC and Standard DC displayed comparable levels of many markers expressed on DC, including HLA-DR, CD83, CD86, CD208 and CCR7. However, compared to Standard DC, mature Fast DC was CD14high CD209low. Fast DC and Standard DC transfected with Jurkat E6-cell mRNA were equally able to elicit T cell specifically recognizing transfected DCs in vitro. IFNgamma-secreting T cells were observed in both the CD4+ and CD8+ subsets. Our results indicate that mature Fast DC are functional antigen presenting cells (APCs) capable of inducing primary T-cell responses, and suggest that these cells may be valuable for generation of anti-tumor vaccines.

Caspase Activation and Aberrant Cell Growth in a p53+/+ Cell Line from a Li-Fraumeni Syndrome Family

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Zaki A. Sherif

2015-01-01

Full Text Available Wild-type p53 is well known to induce cell cycle arrest and apoptosis to block aberrant cell growth. However, p53’s unique role in apoptosis and cell proliferation in Li-Fraumeni Syndrome (LFS has not been well elucidated. The aim of this study is to characterize the activity of wild-type p53 protein in LFS family dominated by a germline negative mutant p53. As expected, etoposide-treated wild-type p53-containing cell lines, LFS 2852 and control Jurkat, showed a greater rate of caspase- and annexin V-induced apoptotic cell death compared to the p53-mutant LFS 2673 cell line although mitochondrial and nuclear assays could not detect apoptosis in these organelles. The most intriguing part of the observation was the abnormal proliferation rate of the wild-type p53-containing cell line, which grew twice as fast as 2673 and Jurkat cells. This is important because apoptosis inducers acting through the mitochondrial death pathway are emerging as promising drugs against tumors where the role of p53 is not only to target gene regulation but also to block cell proliferation. This study casts a long shadow on the possible dysregulation of p53 mediators that enable cell proliferation. The deregulation of proliferation pathways represents an important anticancer therapeutic strategy for patients with the LFS phenotype.

Evaluation of the antioxidant, antibacterial, and antiproliferative ...

African Journals Online (AJOL)

anisaldehyde reagents. The total phenolic content of the extract was determined by Folin-Ciocalteu method and expressed as TAE/g dry weight. The extract was assayed for the in vitro anticancer activity using Jurkat T cells, antioxidant activity using ...

Isoflavones enhance interleukin-17 gene expression via retinoic acid receptor-related orphan receptors α and γ

Science.gov (United States)

Kojima, Hiroyuki; Takeda, Yukimasa; Muromoto, Ryuta; Takahashi, Miki; Hirao, Toru; Takeuchi, Shinji; Jetten, Anton M.; Matsuda, Tadashi

2018-01-01

The retinoic acid receptor-related orphan receptors α and γ (RORα and RORγ), are key regulators of helper T (Th)17 cell differentiation, which is involved in the innate immune system and autoimmune disorders. In this study, we investigated the effects of isoflavones on RORα/γ activity and the gene expression of interleukin (IL)-17, which mediates the function of Th17 cells. In doxycycline-inducible CHO stable cell lines, we found that four isoflavones, biochanin A (BA), genistein, formononetin, and daidzein, enhanced RORα- or RORγ-mediated transcriptional activity in a dose-dependent manner. In an activation assay of the Il17a promoter using Jurkat cells, these compounds enhanced the RORα- or RORγ-mediated activation of the Il17a promoter at concentrations of 1 × 10−6 M to 1 × 10−5 M. In mammalian two-hybrid assays, the four isoflavones enhanced the interaction between the RORα- or RORγ-ligand binding domain and the co-activator LXXLL peptide in a dose-dependent manner. In addition, these isoflavones potently enhanced Il17a mRNA expression in mouse T lymphoma EL4 cells treated with phorbol myristate acetate and ionomycin, but showed slight enhancement of Il17a gene expression in RORα/γ-knockdown EL4 cells. Immunoprecipitation and immunoblotting assays also revealed that BA enhanced the interaction between RORγt and SRC-1, which is a co-activator for nuclear receptors. Taken together, these results suggest that the isoflavones have the ability to enhance IL-17 gene expression by stabilizing the interactions between RORα/γ and co-activators. This also provides the first evidence that dietary chemicals can enhance IL-17 gene expression in immune cells. PMID:25583575

Ultrasound-mediated structural changes in cells revealed by FTIR spectroscopy: A contribution to the optimization of gene and drug delivery

Science.gov (United States)

Grimaldi, Paola; Di Giambattista, Lucia; Giordani, Serena; Udroiu, Ion; Pozzi, Deleana; Gaudenzi, Silvia; Bedini, Angelico; Giliberti, Claudia; Palomba, Raffaele; Congiu Castellano, Agostina

2011-12-01

Ultrasound effects on biological samples are gaining a growing interest concerning in particular, the intracellular delivery of drugs and genes in a safe and in a efficient way. Future progress in this field will require a better understanding of how ultrasound and acoustic cavitation affect the biological system properties. The morphological changes of cells due to ultrasound (US) exposure have been extensively studied, while little attention has been given to the cells structural changes. We have exposed two different cell lines to 1 MHz frequency ultrasound currently used in therapy, Jurkat T-lymphocytes and NIH-3T3 fibroblasts, both employed as models respectively in the apoptosis and in the gene therapy studies. The Fourier Transform Infrared (FTIR) Spectroscopy was used as probe to reveal the structural changes in particular molecular groups belonging to the main biological systems. The genotoxic damage of cells exposed to ultrasound was ascertained by the Cytokinesis-Block Micronucleus (CBMN) assay. The FTIR spectroscopy results, combined with multivariate statistical analysis, regarding all cellular components (lipids, proteins, nucleic acids) of the two cell lines, show that Jurkat cells are more sensitive to therapeutic ultrasound in the lipid and protein regions, whereas the NIH-3T3 cells are more sensitive in the nucleic acids region; a meaningful genotoxic effect is present in both cell lines only for long sonication times while in the Jurkat cells also a significant cytotoxic effect is revealed for long times of exposure to ultrasound.

Fractalkine expression induces endothelial progenitor cell lysis by natural killer cells.

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Dilyana Todorova

Full Text Available BACKGROUND: Circulating CD34(+ cells, a population that includes endothelial progenitors, participate in the maintenance of endothelial integrity. Better understanding of the mechanisms that regulate their survival is crucial to improve their regenerative activity in cardiovascular and renal diseases. Chemokine-receptor cross talk is critical in regulating cell homeostasis. We hypothesized that cell surface expression of the chemokine fractalkine (FKN could target progenitor cell injury by Natural Killer (NK cells, thereby limiting their availability for vascular repair. METHODOLOGY/PRINCIPAL FINDINGS: We show that CD34(+-derived Endothelial Colony Forming Cells (ECFC can express FKN in response to TNF-α and IFN-γ inflammatory cytokines and that FKN expression by ECFC stimulates NK cell adhesion, NK cell-mediated ECFC lysis and microparticles release in vitro. The specific involvement of membrane FKN in these processes was demonstrated using FKN-transfected ECFC and anti-FKN blocking antibody. FKN expression was also evidenced on circulating CD34(+ progenitor cells and was detected at higher frequency in kidney transplant recipients, when compared to healthy controls. The proportion of CD34(+ cells expressing FKN was identified as an independent variable inversely correlated to CD34(+ progenitor cell count. We further showed that treatment of CD34(+ circulating cells isolated from adult blood donors with transplant serum or TNF-α/IFN-γ can induce FKN expression. CONCLUSIONS: Our data highlights a novel mechanism by which FKN expression on CD34(+ progenitor cells may target their NK cell mediated killing and participate to their immune depletion in transplant recipients. Considering the numerous diseased contexts shown to promote FKN expression, our data identify FKN as a hallmark of altered progenitor cell homeostasis with potential implications in better evaluation of vascular repair in patients.

Selection and characterization of T-cell variants lacking molecules involved in T-cell activation (T3 T-cell receptor, T44, and T11): analysis of the functional relationship among different pathways of activation

International Nuclear Information System (INIS)

Moretta, A.; Poggi, A.; Olive, D.; Bottino, C.; Fortis, C.; Pantaleo, G.; Moretta, L.

1987-01-01

A clone of the interleukin 2-producing Jurkat leukemia cell line termed JA3 (surface phenotype, T3 + , Ti + , T44 + , T11 + , T40 + ) has been used to induce and select cell variants lacking surface molecules involved in T-cell activation. Following 200 rad of γ-radiation (1 rad = 0.01 Gy), cells were treated with monoclonal antibodies (mAbs) directed to T3, Ti, T44, or T11 antigen and complement. After growth of the residual cells in culture, negative cells were cloned under limiting conditions. Depending on the specificity of the mAb used for the immunoselection, three groups of variants were obtained. (i) The use of mAbs directed to T3 or Ti resulted in cell variants that expressed the T3 - Ti - T44 + Leu1 + T11 + T40 + 4F2 + HLA class I + surface phenotype. (ii) Immunoselection with anti-T44 mAb resulted in 2 variants that shared the T3 - Ti - T44 - Leu1 - T11 - T40 - 4F2 - HLA class I + phenotype. (iii) Cell treatment with anti-T11 mAb resulted in 15 variants characterized by the lack of T11 antigen expression and of all the other T-cell-specific surface antigens. Therefore, it appears that the different sets of JA3 cell variants, like T cells at discrete stages of intrathymic differentiation, may follow a coordinated expression of surface differentiation antigens. Analysis of the functional responsiveness of the three distinct groups of JA3 cell variants to different stimuli showed that all produced interleukin 2 in response to A23187 calcium ionophore plus phorbol 12-myristate 13-acetate

Light-induced mutagenicity in Salmonella TA102 and genotoxicity/cytotoxicity in human T-cells by 3,3'-dichlorobenzidine: a chemical used in the manufacture of dyes and pigments and in tattoo inks

International Nuclear Information System (INIS)

Wang Lei; Yan Jian; Hardy, William; Mosley, Charity; Wang Shuguang; Yu Hongtao

2005-01-01

DCB, 3,3'-dichlorobenzidine, is used primarily as an intermediate in the manufacture of diarylide yellow or azo red pigments for printing ink, textile, paint, and plastics. It is also used in tattoo inks. In this article, we investigate light-induced toxicity of DCB in both bacteria and human Jurkat T-cells. DCB itself is not toxic or mutagenic to Salmonella typhimurium TA102, but is photomutagenic at concentrations as low as 2 μM and phototoxic at concentrations >100 μM when bacteria are exposed to DCB and light at the same time (1.2 J/cm 2 of UVA and 2.1 J/cm 2 of visible light). Furthermore, DCB is both photocytotoxic and photogenotoxic to human Jurkat T-cells. Under a light irradiation dose of 2.3 J/cm 2 of UVA and 4.2 J/cm 2 of visible light, it causes the Jurkat T-cells to become nonviable in a DCB dose-dependent manner and the nonviable cells reaches 60% at DCB concentrations higher than 50 μM. At the same time, DNA fragmentation is observed for cells exposed to both DCB and light, determined by single cell gel electrophoresis (alkaline comet assay). As much as 5% (average) DNA fragmentation was observed when exposed to 200 μM DCB and light irradiation. This suggests that DCB can penetrate the cell membrane and enter the cell. Upon light activation, DCB in the cells can cause various cellular damages, leading to nonviable Jurkat T-cells. It appears, the nonviable cells are not caused solely by fragmentation of cellular DNA, but by other damages such as to proteins and cell membranes, or DNA alkylation. Therefore, persons exposed to DCB through environmental contamination or through tattoo piercing using DCB-containing inks must not only concern about its toxicity without exposing to light, but also its phototoxicity

Behavioral experience induces zif268 expression in mature granule cells but suppresses its expression in immature granule cells

Science.gov (United States)

Huckleberry, Kylie A.; Kane, Gary A.; Mathis, Rita J.; Cook, Sarah G.; Clutton, Jonathan E.; Drew, Michael R.

2015-01-01

Thousands of neurons are born each day in the dentate gyrus (DG), but many of these cells die before reaching maturity. Both death and survival of adult-born neurons are regulated by neuronal activity in the DG. The immediate-early gene (IEG) zif268 appears to be an important mediator of these effects, as its expression can be induced by neural activity and knockout of zif268 impairs survival of adult-born neurons (Richardson et al., 1992; Veyrac et al., 2013). Despite the apparent importance of zif268 for adult neurogenesis, its behavior-induced expression has not been fully characterized in adult-born neurons. Here we characterize behavior-evoked expression of zif268 in mature and newborn dentate granule cells (DGCs). We first quantified zif268 expression in doublecortin-positive (DCX+) immature neurons and in the general granule cell population after brief exposure to a novel environment (NE). In the general granule cell population, zif268 expression peaked 1 h after NE exposure and returned to baseline by 8 h post-exposure. However, in the DCX+ cells, zif268 expression was suppressed relative to home cage for at least 8 h post-exposure. We next asked whether suppression of zif268 in DCX+ immature cells occurs in other behavioral paradigms that recruit the hippocampus. Exposure to Morris water maze (MWM) training, an enriched environment, or a NE caused approximately equal suppression of zif268 expression in DCX+ cells and approximately equal activation of zif268 expression among the general granule cell population. The same behavioral procedures activated zif268 expression in 6-week-old BrdU-labeled adult-born neurons, indicating that zif268 suppression is specific to immature neurons. Finally, we asked whether zif268 suppression varied as a function of age within the DCX+ population, which ranges in age from 0 to approximately 4 weeks. NE exposure had no significant effect on zif268 expression in 2- or 4-week-old BrdU-labeled neurons, but it significantly

Assembly of the T-cell antigen receptor. Participation of the CD3 omega chain

DEFF Research Database (Denmark)

Neisig, A; Vangsted, A; Zeuthen, J

1993-01-01

The human TCR is composed of the Ti alpha beta heterodimer in association with the CD3 chains CD3 gamma delta epsilon zeta 2. Another chain, referred to as CD3 omega, has recently been described in T cells. CD3 omega is an intracellular protein transiently associated with the CD3 complex during...... the assembly of the TCR in the endoplasmic reticulum (ER) and it is not expressed on the cell surface. The function of CD3 omega is unknown but it has been suggested that it plays an important role in the assembly of the TCR. We have studied the possible function of CD3 omega in the human leukemic T-cell line...... Jurkat and different variants of this cell line. Cells were metabolically labeled, subjected to lysis, immunoprecipitated, and analyzed by SDS-PAGE. The results indicate that: 1) CD3 omega associates primarily with the CD3 delta epsilon complex; 2) CD3 omega is not associated with single Ti alpha or Ti...

Cationic Amphiphilic Tris-Cyclometalated Iridium(III) Complexes Induce Cancer Cell Death via Interaction with Ca2+-Calmodulin Complex.

Science.gov (United States)

Hisamatsu, Yosuke; Suzuki, Nozomi; Masum, Abdullah-Al; Shibuya, Ai; Abe, Ryo; Sato, Akira; Tanuma, Sei-Ichi; Aoki, Shin

2017-02-15

In our previous paper, we reported on the preparation of some cationic amphiphilic Ir complexes (2c, 2d) containing KKGG peptides that induce and detect cell death of Jurkat cells. Mechanistic studies suggest that 2c interacts with anionic molecules and/or membrane receptors on the cell surface to trigger an intracellular Ca 2+ response, resulting in the induction of cell death, accompanied by membrane disruption. We have continued the studies of cell death of Jurkat cells induced by 2c and found that xestospongin C, a selective inhibitor of an inositol 1,4,5-trisphosphate receptor located on the endoplasmic reticulum (ER), reduces the cytotoxicity of 2c, suggesting that 2c triggers the release of Ca 2+ from the ER, leading to an increase in the concentration of cytosolic Ca 2+ , thus inducing cell death. Moreover, we synthesized a series of new amphiphilic cationic Ir complexes 5a-c containing photoreactive 3-trifluoromethyl-3-phenyldiazirine (TFPD) groups, in an attempt to identify the target molecules of 2c. Interestingly, it was discovered that a TFPD group functions as a triplet quencher of Ir complexes. It was also found that 5b is useful as a turn-on phosphorescent probe of acidic proteins such as bovine serum albumin (BSA) (pI = 4.7) and their complexation was confirmed by luminescence titrations and SDS-PAGE of photochemical products between them. These successful results allowed us to carry out photoaffinity labeling of the target biomolecules of 5b (2c and analogues thereof) in Jurkat cells. A proteomic analysis of the products obtained by the photoirradiation of 5b with Jurkat cells suggests that the Ca 2+ -binding protein "calmodulin (CaM)" is one of target proteins of the Ir complexes. Indeed, 5b was found to interact with the Ca 2+ -CaM complex, as evidenced by luminescence titrations and the results of photochemical reactions of 5b with CaM in the presence of Ca 2+ (SDS-PAGE). A plausible mechanism for cell death induced by a cationic amphiphilic Ir

Tropomyosin Receptor Kinase A Expression on Merkel Cell Carcinoma Cells.

Science.gov (United States)

Wehkamp, Ulrike; Stern, Sophie; Krüger, Sandra; Hauschild, Axel; Röcken, Christoph; Egberts, Friederike

2017-11-01

Merkel cell carcinoma (MCC) is a malignant neuroendocrine skin tumor frequently associated with the Merkel cell polyomavirus. Immune checkpoint therapy showed remarkable results, although not all patients are responsive to this therapy. Anti-tropomyosin receptor kinase A (TrkA)-targeted treatment has shown promising results in several tumor entities. To determine TrkA expression in MCC as a rationale for potential targeted therapy. This case series study investigated the MCC specimens of 55 patients treated at the Department of Dermatology, University Hospital of Schleswig-Holstein, Kiel, Germany, from January 1, 2005, through December 31, 2015. Thirty-nine of the 55 samples were suitable for further histopathologic examination. Expression of TrkA was explored by immunohistochemical analysis. Diagnosis of MCC was confirmed by staining positive for cytokeratin 20 (CK20) and synaptophysin. Expression of TrkA on the tumor cells. Specimens of 39 patients (21 women and 18 men; mean [SD] age, 75.0 [7.8] years) underwent immunohistochemical investigation. Thirty-eight of 38 specimens expressed CK20 and synaptophysin on the MCC tumor cells (100% expression). Merkel cell polyomavirus was detected in 32 of 38 specimens (84%). Tropomyosin receptor kinase A was found in all 36 evaluable specimens on the tumor cells; 34 (94%) showed a weak and 2 (6%) showed a strong cytoplasmic expression. In addition, strongly positive perinuclear dots were observed in 30 of 36 specimens (83%). Tropomyosin receptor kinase A was expressed on MCC tumor cells in 100% of evaluable specimens. This result may lead to the exploration of new targeted treatment options in MCC, especially for patients who do not respond to anti-programmed cell death protein 1 treatment.

Determining Physical Mechanisms of Gene Expression Regulation from Single Cell Gene Expression Data

OpenAIRE

Ezer, Daphne; Moignard, Victoria; G?ttgens, Berthold; Adryan, Boris

2016-01-01

Many genes are expressed in bursts, which can contribute to cell-to-cell heterogeneity. It is now possible to measure this heterogeneity with high throughput single cell gene expression assays (single cell qPCR and RNA-seq). These experimental approaches generate gene expression distributions which can be used to estimate the kinetic parameters of gene expression bursting, namely the rate that genes turn on, the rate that genes turn off, and the rate of transcription. We construct a complete ...

Expression of stanniocalcin 1 in thyroid side population cells and thyroid cancer cells.

Science.gov (United States)

Hayase, Suguru; Sasaki, Yoshihito; Matsubara, Tsutomu; Seo, Daekwan; Miyakoshi, Masaaki; Murata, Tsubasa; Ozaki, Takashi; Kakudo, Kennichi; Kumamoto, Kensuke; Ylaya, Kris; Cheng, Sheue-yann; Thorgeirsson, Snorri S; Hewitt, Stephen M; Ward, Jerrold M; Kimura, Shioko

2015-04-01

Mouse thyroid side population (SP) cells consist of a minor population of mouse thyroid cells that may have multipotent thyroid stem cell characteristics. However the nature of thyroid SP cells remains elusive, particularly in relation to thyroid cancer. Stanniocalcin (STC) 1 and 2 are secreted glycoproteins known to regulate serum calcium and phosphate homeostasis. In recent years, the relationship of STC1/2 expression to cancer has been described in various tissues. Microarray analysis was carried out to determine genes up- and down-regulated in thyroid SP cells as compared with non-SP cells. Among genes up-regulated, stanniocalcin 1 (STC1) was chosen for study because of its expression in various thyroid cells by Western blotting and immunohistochemistry. Gene expression analysis revealed that genes known to be highly expressed in cancer cells and/or involved in cancer invasion/metastasis were markedly up-regulated in SP cells from both intact as well as partial thyroidectomized thyroids. Among these genes, expression of STC1 was found in five human thyroid carcinoma-derived cell lines as revealed by analysis of mRNA and protein, and its expression was inversely correlated with the differentiation status of the cells. Immunohistochemical analysis demonstrated higher expression of STC1 in the thyroid tumor cell line and thyroid tumor tissues from humans and mice. These results suggest that SP cells contain a population of cells that express genes also highly expressed in cancer cells including Stc1, which warrants further study on the role of SP cells and/or STC1 expression in thyroid cancer.

Rho GTPase expression in human myeloid cells.

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Suzanne F G van Helden

Full Text Available Myeloid cells are critical for innate immunity and the initiation of adaptive immunity. Strict regulation of the adhesive and migratory behavior is essential for proper functioning of these cells. Rho GTPases are important regulators of adhesion and migration; however, it is unknown which Rho GTPases are expressed in different myeloid cells. Here, we use a qPCR-based approach to investigate Rho GTPase expression in myeloid cells.We found that the mRNAs encoding Cdc42, RhoQ, Rac1, Rac2, RhoA and RhoC are the most abundant. In addition, RhoG, RhoB, RhoF and RhoV are expressed at low levels or only in specific cell types. More differentiated cells along the monocyte-lineage display lower levels of Cdc42 and RhoV, while RhoC mRNA is more abundant. In addition, the Rho GTPase expression profile changes during dendritic cell maturation with Rac1 being upregulated and Rac2 downregulated. Finally, GM-CSF stimulation, during macrophage and osteoclast differentiation, leads to high expression of Rac2, while M-CSF induces high levels of RhoA, showing that these cytokines induce a distinct pattern. Our data uncover cell type specific modulation of the Rho GTPase expression profile in hematopoietic stem cells and in more differentiated cells of the myeloid lineage.

Human surfactant protein D alters oxidative stress and HMGA1 expression to induce p53 apoptotic pathway in eosinophil leukemic cell line.

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Lakshna Mahajan

Full Text Available Surfactant protein D (SP-D, an innate immune molecule, has an indispensable role in host defense and regulation of inflammation. Immune related functions regulated by SP-D include agglutination of pathogens, phagocytosis, oxidative burst, antigen presentation, T lymphocyte proliferation, cytokine secretion, induction of apoptosis and clearance of apoptotic cells. The present study unravels a novel ability of SP-D to reduce the viability of leukemic cells (eosinophilic leukemic cell line, AML14.3D10; acute myeloid leukemia cell line, THP-1; acute lymphoid leukemia cell lines, Jurkat, Raji; and human breast epithelial cell line, MCF-7, and explains the underlying mechanisms. SP-D and a recombinant fragment of human SP-D (rhSP-D induced G2/M phase cell cycle arrest, and dose and time-dependent apoptosis in the AML14.3D10 eosinophilic leukemia cell line. Levels of various apoptotic markers viz. activated p53, cleaved caspase-9 and PARP, along with G2/M checkpoints (p21 and Tyr15 phosphorylation of cdc2 showed significant increase in these cells. We further attempted to elucidate the underlying mechanisms of rhSP-D induced apoptosis using proteomic analysis. This approach identified large scale molecular changes initiated by SP-D in a human cell for the first time. Among others, the proteomics analysis highlighted a decreased expression of survival related proteins such as HMGA1, overexpression of proteins to protect the cells from oxidative burst, while a drastic decrease in mitochondrial antioxidant defense system. rhSP-D mediated enhanced oxidative burst in AML14.3D10 cells was confirmed, while antioxidant, N-acetyl-L-cysteine, abrogated the rhSP-D induced apoptosis. The rhSP-D mediated reduced viability was specific to the cancer cell lines and viability of human PBMCs from healthy controls was not affected. The study suggests involvement of SP-D in host's immunosurveillance and therapeutic potential of rhSP-D in the eosinophilic leukemia and

Forced Expression of ZNF143 Restrains Cancer Cell Growth

International Nuclear Information System (INIS)

Izumi, Hiroto; Yasuniwa, Yoshihiro; Akiyama, Masaki; Yamaguchi, Takahiro; Kuma, Akihiro; Kitamura, Noriaki; Kohno, Kimitoshi

2011-01-01

We previously reported that the transcription factor Zinc Finger Protein 143 (ZNF143) regulates the expression of genes associated with cell cycle and cell division, and that downregulation of ZNF143 induces cell cycle arrest at G2/M. To assess the function of ZNF143 expression in the cell cycle, we established two cells with forced expression of ZNF143 derived from PC3 prostate cancer cell lines. These cell lines overexpress genes associated with cell cycle and cell division, such as polo-like kinase 1 (PLK1), aurora kinase B (AURKB) and some minichromosome maintenance complex components (MCM). However, the doubling time of cells with forced expression of ZNF143 was approximately twice as long as its control counterpart cell line. Analysis following serum starvation and re-seeding showed that PC3 cells were synchronized at G1 in the cell cycle. Also, ZNF143 expression fluctuated, and was at its lowest level in G2/M. However, PC3 cells with forced expression of ZNF143 synchronized at G2/M, and showed lack of cell cycle-dependent fluctuation of nuclear expression of MCM proteins. Furthermore, G2/M population of both cisplatin-resistant PCDP6 cells over-expressing ZNF143 (derived from PC3 cells) and cells with forced expression of ZNF143 was significantly higher than that of each counterpart, and the doubling time of PCDP6 cells is about 2.5 times longer than that of PC3 cells. These data suggested that fluctuations in ZNF143 expression are required both for gene expression associated with cell cycle and for cell division

Forced Expression of ZNF143 Restrains Cancer Cell Growth

Energy Technology Data Exchange (ETDEWEB)

Izumi, Hiroto, E-mail: h-izumi@med.uoeh-u.ac.jp; Yasuniwa, Yoshihiro; Akiyama, Masaki; Yamaguchi, Takahiro; Kuma, Akihiro; Kitamura, Noriaki; Kohno, Kimitoshi [Department of Molecular Biology, School of Medicine, University of Occupational and Environmental Health, 1-1 Iseigaoka, Yahatanishi-ku, Kitakyushu 807-8555 (Japan)

2011-10-19

We previously reported that the transcription factor Zinc Finger Protein 143 (ZNF143) regulates the expression of genes associated with cell cycle and cell division, and that downregulation of ZNF143 induces cell cycle arrest at G2/M. To assess the function of ZNF143 expression in the cell cycle, we established two cells with forced expression of ZNF143 derived from PC3 prostate cancer cell lines. These cell lines overexpress genes associated with cell cycle and cell division, such as polo-like kinase 1 (PLK1), aurora kinase B (AURKB) and some minichromosome maintenance complex components (MCM). However, the doubling time of cells with forced expression of ZNF143 was approximately twice as long as its control counterpart cell line. Analysis following serum starvation and re-seeding showed that PC3 cells were synchronized at G1 in the cell cycle. Also, ZNF143 expression fluctuated, and was at its lowest level in G2/M. However, PC3 cells with forced expression of ZNF143 synchronized at G2/M, and showed lack of cell cycle-dependent fluctuation of nuclear expression of MCM proteins. Furthermore, G2/M population of both cisplatin-resistant PCDP6 cells over-expressing ZNF143 (derived from PC3 cells) and cells with forced expression of ZNF143 was significantly higher than that of each counterpart, and the doubling time of PCDP6 cells is about 2.5 times longer than that of PC3 cells. These data suggested that fluctuations in ZNF143 expression are required both for gene expression associated with cell cycle and for cell division.

Forced Expression of ZNF143 Restrains Cancer Cell Growth

Directory of Open Access Journals (Sweden)

Kimitoshi Kohno

2011-10-01

Full Text Available We previously reported that the transcription factor Zinc Finger Protein 143 (ZNF143 regulates the expression of genes associated with cell cycle and cell division, and that downregulation of ZNF143 induces cell cycle arrest at G2/M. To assess the function of ZNF143 expression in the cell cycle, we established two cells with forced expression of ZNF143 derived from PC3 prostate cancer cell lines. These cell lines overexpress genes associated with cell cycle and cell division, such as polo-like kinase 1 (PLK1, aurora kinase B (AURKB and some minichromosome maintenance complex components (MCM. However, the doubling time of cells with forced expression of ZNF143 was approximately twice as long as its control counterpart cell line. Analysis following serum starvation and re-seeding showed that PC3 cells were synchronized at G1 in the cell cycle. Also, ZNF143 expression fluctuated, and was at its lowest level in G2/M. However, PC3 cells with forced expression of ZNF143 synchronized at G2/M, and showed lack of cell cycle-dependent fluctuation of nuclear expression of MCM proteins. Furthermore, G2/M population of both cisplatin-resistant PCDP6 cells over-expressing ZNF143 (derived from PC3 cells and cells with forced expression of ZNF143 was significantly higher than that of each counterpart, and the doubling time of PCDP6 cells is about 2.5 times longer than that of PC3 cells. These data suggested that fluctuations in ZNF143 expression are required both for gene expression associated with cell cycle and for cell division.

CD25+ B-1a Cells Express Aicda

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Hiroaki Kaku

2017-06-01

Full Text Available B-1a cells are innate-like B-lymphocytes producing natural antibodies. Activation-induced cytidine deaminase (AID, a product of the Aicda gene, plays a central role in class-switch recombination and somatic hypermutation in B cells. Although a role for Aicda in B-1a cells has been suggested on the basis of experiments with knock out (KO mice, whether B-1a cells express Aicda, and if so, which B-1a cell subpopulation expresses Aicda, remains unknown. Here, we demonstrate that B-1 cells express Aicda, but at a level below that expressed by germinal center (GC B cells. We previously reported that B-1a cells can be subdivided based on CD25 expression. We show here that B-1a cell Aicda expression is concentrated in the CD25+ B-1a cell subpopulation. These results suggest the possibility that previous studies of memory B cells identified on the basis of Aicda expression may have inadvertently included an unknown number of CD25+ B-1a cells. Although B-1a cells develop normally in the absence of Aicda, a competitive reconstitution assay reveals enhanced vigor for AID KO B-1a cell bone marrow (BM progenitors, as compared with wild-type BM B-1 cell progenitors. These results suggest that AID inhibits the development of B-1a cells from BM B-1 cell progenitors in a competitive environment.

Novel Biophysical Marker of Aggressive Prostate Cancer Cells

Science.gov (United States)

2013-06-01

756 30.33 PrEC LHSR 8.60 687 19.71 PC-3 9.31 744 48.42 TEM 4–18 8.55 683 45.00 22Rv1 7.27 581 41.00 MD.MBA.231 8.16 652 32.43 B16.f0 9.11 728 37.37 Panc ...established human cancer cell lines evaluated, PANC -1 pancreatic cancer cells and Jurkat leukemia cells, were considerably more sensitive to the FSS

During development intense Sox2 expression marks not only Prox1-expressing taste bud cell but also perigemmal cell lineages.

Science.gov (United States)

Nakayama, Ayumi; Miura, Hirohito; Ooki, Makoto; Harada, Shuitsu

2015-03-01

Sox2 is proposed to regulate the differentiation of bipotential progenitor cells into taste bud cells. However, detailed expression of Sox2 remains unclear. In this report, Sox2 expression during taste bud development in the fungiform (FF), circumvallate (CV) and soft palate (SP) areas is examined together with Prox1. First, we immunohistochemically checked Prox1 expression in adults and found that almost all taste bud cells are Prox1-positive. During FF development, intense Sox2 expression was restricted to taste bud primordia expressing Prox1 at E12.5. However, at E14.5, Sox2 was intensely expressed outside the developing taste buds resolving to perigemmal Sox2 expression in adults. In the SP, at E14.5, taste bud primordia emerged as Prox1-expressing cell clusters. However, intense Sox2 expression was not restricted to taste bud primordia but was detected widely in the epithelium. During development, Sox2 expression outside developing taste buds was generally down-regulated but was retained in the perigemmal region similarly to that in the FF. In the CV, the initial stage of taste bud development remained unclear because of the lack of taste bud primordia comparable to that in the FF and SP. Here, we show that Prox1-expressing cells appear in the apical epithelium at E12.5, in the inner trench wall at E17.5 and in the outer trench wall at E18.5. Sox2 was again not restricted to developing taste bud cells expressing Prox1 during CV development. The expression patterns support that Sox2 does not serve as a cell fate selector between taste bud cells and surrounding keratinocytes but rather may contribute to them both.

Decorin expression in quiescent myogenic cells

International Nuclear Information System (INIS)

Nishimura, Takanori; Nozu, Kenjiro; Kishioka, Yasuhiro; Wakamatsu, Jun-ichi; Hattori, Akihito

2008-01-01

Satellite cells are quiescent muscle stem cells that promote postnatal muscle growth and repair. When satellite cells are activated by myotrauma, they proliferate, migrate, differentiate, and ultimately fuse to existing myofibers. The remainder of these cells do not differentiate, but instead return to quiescence and remain in a quiescent state until activation begins the process again. This ability to maintain their own population is important for skeletal muscle to maintain the capability to repair during postnatal life. However, the mechanisms by which satellite cells return to quiescence and maintain the quiescent state are still unclear. Here, we demonstrated that decorin mRNA expression was high in cell cultures containing a higher ratio of quiescent satellite cells when satellite cells were stimulated with various concentrations of hepatocyte growth factor. This result suggests that quiescent satellite cells express decorin at a high level compared to activated satellite cells. Furthermore, we examined the expression of decorin in reserve cells, which were undifferentiated myoblasts remaining after induction of differentiation by serum-deprivation. Decorin mRNA levels in reserve cells were higher than those in differentiated myotubes and growing myoblasts. These results suggest that decorin participates in the quiescence of myogenic cells

(Asteraceae) Fraction against Human Cancer Cell Lines

African Journals Online (AJOL)

Purpose: To investigate the anti-proliferative and apoptotic activity of crude and dichloromethane fraction of A. sieberi against seven cancer cell lines (Colo20, HCT116, DLD, MCF7, Jurkat, HepG2 and L929). Methods: A. sieberi was extracted with methanol and further purification was carried out using liquidliquid extraction ...

Shb deficient mice display an augmented T(H)2 response in peripheral CD4+T cells

Czech Academy of Sciences Publication Activity Database

Gustafsson, K.; Calounova, G.; Hjelm, F.; Kříž, Vitězslav; Heyman, B.; Gronvik, K.O.; Mostoslavsky, G.; Welsh, M.

2011-01-01

Roč. 12, č. 3 (2011) ISSN 1471-2172 Institutional support: RVO:68081707 Keywords : DOMAIN PROTEIN SHB * JURKAT T-CELLS * ANTIGEN RECEPTOR Subject RIV: BO - Biophysics Impact factor: 2.531, year: 2011

The activation of p38 MAPK primarily contributes to UV-induced RhoB expression by recruiting the c-Jun and p300 to the distal CCAAT box of the RhoB promoter

International Nuclear Information System (INIS)

Ahn, Jiwon; Choi, Jeong-Hae; Won, Misun; Kang, Chang-Mo; Gyun, Mi-Rang; Park, Hee-Moon; Kim, Chun-Ho; Chung, Kyung-Sook

2011-01-01

Highlights: → Regulation of transcriptional activation of RhoB is still unclear. → We examine the effect of p38 MAPK inhibition, and c-Jun and RhoB depletion on UV-induced RhoB expression and apoptosis. → We identify the regions of RhoB promoter necessary to confer UV responsiveness using pRhoB-luciferase reporter assays. → c-Jun, ATF2 and p300 are dominantly associated with NF-Y on the distal CCAAT box. → The activation of p38 MAPK primarily contribute to UV-induced RhoB expression by recruiting the c-Jun and p300 proteins on distal CCAAT box of RhoB promoter. -- Abstract: The Ras-related small GTP-binding protein RhoB is rapidly induced in response to genotoxic stresses caused by ionizing radiation. It is known that UV-induced RhoB expression results from the binding of activating transcription factor 2 (ATF2) via NF-Y to the inverted CCAAT box (-23) of the RhoB promoter. Here, we show that the association of c-Jun with the distal CCAAT box (-72) is primarily involved in UV-induced RhoB expression and p38 MAPK regulated RhoB induction through the distal CCAAT box. UV-induced RhoB expression and apoptosis were markedly attenuated by pretreatment with the p38 MAPK inhibitor. siRNA knockdown of RhoB, ATF2 and c-Jun resulted in decreased RhoB expression and eventually restored the growth of UV-irradiated Jurkat cells. In the reporter assay using luciferase under the RhoB promoter, inhibition of RhoB promoter activity by the p38 inhibitor and knockdown of c-Jun using siRNA occurred through the distal CCAAT box. Immunoprecipitation and DNA affinity protein binding assays revealed the association of c-Jun and p300 via NF-YA and the dissociation of histone deacetylase 1 (HDAC1) via c-Jun recruitment to the CCAAT boxes of the RhoB promoter. These results suggest that the activation of p38 MAPK primarily contributes to UV-induced RhoB expression by recruiting the c-Jun and p300 proteins to the distal CCAAT box of the RhoB promoter in Jurkat cells.

Haemopedia: An Expression Atlas of Murine Hematopoietic Cells

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Carolyn A. de Graaf

2016-09-01

Full Text Available Hematopoiesis is a multistage process involving the differentiation of stem and progenitor cells into distinct mature cell lineages. Here we present Haemopedia, an atlas of murine gene-expression data containing 54 hematopoietic cell types, covering all the mature lineages in hematopoiesis. We include rare cell populations such as eosinophils, mast cells, basophils, and megakaryocytes, and a broad collection of progenitor and stem cells. We show that lineage branching and maturation during hematopoiesis can be reconstructed using the expression patterns of small sets of genes. We also have identified genes with enriched expression in each of the mature blood cell lineages, many of which show conserved lineage-enriched expression in human hematopoiesis. We have created an online web portal called Haemosphere to make analyses of Haemopedia and other blood cell transcriptional datasets easier. This resource provides simple tools to interrogate gene-expression-based relationships between hematopoietic cell types and genes of interest.

In situ detection of a heat-shock regulatory element binding protein using a soluble short synthetic enhancer sequence

Energy Technology Data Exchange (ETDEWEB)

Harel-Bellan, A; Brini, A T; Farrar, W L [National Cancer Institute, Frederick, MD (USA); Ferris, D K [Program Resources, Inc., Frederick, MD (USA); Robin, P [Institut Gustave Roussy, Villejuif (France)

1989-06-12

In various studies, enhancer binding proteins have been successfully absorbed out by competing sequences inserted into plasmids, resulting in the inhibition of the plasmid expression. Theoretically, such a result could be achieved using synthetic enhancer sequences not inserted into plasmids. In this study, a double stranded DNA sequence corresponding to the human heat shock regulatory element was chemically synthesized. By in vitro retardation assays, the synthetic sequence was shown to bind specifically a protein in extracts from the human T cell line Jurkat. When the synthetic enhancer was electroporated into Jurkat cells, not only the enhancer was shown to remain undegraded into the cells for up to 2 days, but also its was shown to bind intracellularly a protein. The binding was specific and was modulated upon heat shock. Furthermore, the binding protein was shown to be of the expected molecular weight by UV crosslinking. However, when the synthetic enhancer element was co-electroporated with an HSP 70-CAT reporter construct, the expression of the reporter plasmid was consistently enhanced in the presence of the exogenous synthetic enhancer.

Magnetic manipulation device for the optimization of cell processing conditions.

Science.gov (United States)

Ito, Hiroshi; Kato, Ryuji; Ino, Kosuke; Honda, Hiroyuki

2010-02-01

Variability in human cell phenotypes make it's advancements in optimized cell processing necessary for personalized cell therapy. Here we propose a strategy of palm-top sized device to assist physically manipulating cells for optimizing cell preparations. For the design of such a device, we combined two conventional approaches: multi-well plate formatting and magnetic cell handling using magnetite cationic liposomes (MCLs). From our previous works, we showed the labeling applications of MCL on adhesive cells for various tissue engineering approaches. To feasibly transfer cells in multi-well plate, we here evaluated the magnetic response of MCL-labeled suspension type cells. The cell handling performance of Jurkat cells proved to be faster and more robust compared to MACS (Magnetic Cell Sorting) bead methods. To further confirm our strategy, prototype palm-top sized device "magnetic manipulation device (MMD)" was designed. In the device, the actual cell transportation efficacy of Jurkat cells was satisfying. Moreover, as a model of the most distributed clinical cell processing, primary peripheral blood mononuclear cells (PBMCs) from different volunteers were evaluated. By MMD, individual PBMCs indicated to have optimum Interleukin-2 (IL-2) concentrations for the expansion. Such huge differences of individual cells indicated that MMD, our proposing efficient and self-contained support tool, could assist the feasible and cost-effective optimization of cell processing in clinical facilities. Copyright (c) 2009 The Society for Biotechnology, Japan. Published by Elsevier B.V. All rights reserved.

Foxp3 expression in human cancer cells

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Gourgoulianis Konstantinos I

2008-04-01

Full Text Available Abstract Objective Transcription factor forkhead box protein 3 (Foxp3 specifically characterizes the thymically derived naturally occurring regulatory T cells (Tregs. Limited evidence indicates that it is also expressed, albeit to a lesser extent, in tissues other than thymus and spleen, while, very recently, it was shown that Foxp3 is expressed by pancreatic carcinoma. This study was scheduled to investigate whether expression of Foxp3 transcripts and mature protein occurs constitutively in various tumor types. Materials and methods Twenty five tumor cell lines of different tissue origins (lung cancer, colon cancer, breast cancer, melanoma, erythroid leukemia, acute T-cell leukemia were studied. Detection of Foxp3 mRNA was performed using both conventional RT-PCR and quantitative real-time PCR while protein expression was assessed by immunocytochemistry and flow cytometry, using different antibody clones. Results Foxp3 mRNA as well as Foxp3 protein was detected in all tumor cell lines, albeit in variable levels, not related to the tissue of origin. This expression correlated with the expression levels of IL-10 and TGFb1. Conclusion We offer evidence that Foxp3 expression, characterizes tumor cells of various tissue origins. The biological significance of these findings warrants further investigation in the context of tumor immune escape, and especially under the light of current anti-cancer efforts interfering with Foxp3 expression.

Arsenic, cadmium, and manganese levels in shellfish from Map Ta Phut, an industrial area in Thailand, and the potential toxic effects on human cells.

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Rangkadilok, Nuchanart; Siripriwon, Pantaree; Nookabkaew, Sumontha; Suriyo, Tawit; Satayavivad, Jutamaad

2015-01-01

Map Ta Phut Industrial Estate is a major industrial area in Thailand for both petrochemical and heavy industries. The release of hazardous wastes and other pollutants from these industries increases the potential for contamination in foods in the surrounding area, especially farmed shellfish. This study determined the arsenic (As), cadmium (Cd), and manganese (Mn) concentrations in the edible flesh of farmed shellfish, including Perna viridis, Meretrix meretrix, and Scapharca inaequivalvis, around the Map Ta Phut area using inductively coupled plasma mass spectrometry. The results showed that shellfish samples contained high levels of total As [1.84-6.42 mg kg(-1) wet weight (ww)]. High Mn concentrations were found in P. viridis and M. meretrix, whereas S. inaequivalis contained the highest Cd. Arsenobetaine (AsB) was found to be the major As species in shellfish (>45% of total As). The in vitro cytotoxicity of these elements was evaluated using human cancer cells (T47D, A549, and Jurkat cells). An observed decrease in cell viability in T47D and Jurkat cells was mainly caused by exposure to inorganic As (iAs) or Mn but not to AsB or Cd. The combined elements (AsB+Mn+Cd) at concentrations predicted to result from the estimated daily intake of shellfish flesh by the local people showed significant cytotoxicity in T47D and Jurkat cells.

Isoflavones enhance interleukin-17 gene expression via retinoic acid receptor-related orphan receptors α and γ

International Nuclear Information System (INIS)

Kojima, Hiroyuki; Takeda, Yukimasa; Muromoto, Ryuta; Takahashi, Miki; Hirao, Toru; Takeuchi, Shinji; Jetten, Anton M.; Matsuda, Tadashi

2015-01-01

Highlights: • Nuclear receptors, RORα and RORγ, are key regulators of Th17 cell differentiation. • Isoflavones have RORα/γ agonistic activities. • Isoflavones enhance the interaction of RORα/γ with co-activator. • These compounds enhance the expression of Il17a mRNA in mouse EL4 cells. • Dietary isoflavones can act as modulators of Il17a expression via RORα/γ. - Abstract: The retinoic acid receptor-related orphan receptors α and γ (RORα and RORγ), are key regulators of helper T (Th)17 cell differentiation, which is involved in the innate immune system and autoimmune disorders. In this study, we investigated the effects of isoflavones on RORα/γ activity and the gene expression of interleukin (IL)-17, which mediates the function of Th17 cells. In doxycycline-inducible CHO stable cell lines, we found that four isoflavones, biochanin A (BA), genistein, formononetin, and daidzein, enhanced RORα- or RORγ-mediated transcriptional activity in a dose-dependent manner. In an activation assay of the Il17a promoter using Jurkat cells, these compounds enhanced the RORα- or RORγ-mediated activation of the Il17a promoter at concentrations of 1 × 10 −6 M to 1 × 10 −5 M. In mammalian two-hybrid assays, the four isoflavones enhanced the interaction between the RORα- or RORγ-ligand binding domain and the co-activator LXXLL peptide in a dose-dependent manner. In addition, these isoflavones potently enhanced Il17a mRNA expression in mouse T lymphoma EL4 cells treated with phorbol myristate acetate and ionomycin, but showed slight enhancement of Il17a gene expression in RORα/γ-knockdown EL4 cells. Immunoprecipitation and immunoblotting assays also revealed that BA enhanced the interaction between RORγt and SRC-1, which is a co-activator for nuclear receptors. Taken together, these results suggest that the isoflavones have the ability to enhance IL-17 gene expression by stabilizing the interactions between RORα/γ and co-activators. This also

Functional requirements for inhibitory signal transmission by the immunomodulatory receptor CD300a.

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DeBell, Karen E; Simhadri, Venkateswara R; Mariano, John L; Borrego, Francisco

2012-04-26

Activation signals can be negatively regulated by cell surface receptors bearing immunoreceptor tyrosine-based inhibitory motifs (ITIMs). CD300a, an ITIM bearing type I transmembrane protein, is expressed on many hematopoietic cells, including subsets of lymphocytes. We have taken two approaches to further define the mechanism by which CD300a acts as an inhibitor of immune cell receptor signaling. First, we have expressed in Jurkat T cells a chimeric receptor consisting of the extracellular domains of killer-cell immunoglobulin-like receptor (KIR)2DL2 fused to the transmembrane and cytoplasmic segments of CD300a (KIR-CD300a) to explore surrogate ligand-stimulated inhibition of superantigen stimulated T cell receptor (TCR) mediated cell signaling. We found that intact CD300a ITIMs were essential for inhibition and that the tyrosine phosphorylation of these ITIMs required the src tyrosine kinase Lck. Tyrosine phosphorylation of the CD300a ITIMs created docking sites for both src homology 2 domain containing protein tyrosine phosphatase (SHP)-1 and SHP-2. Suppression of SHP-1 and SHP-2 expression in KIR-CD300a Jurkat T cells with siRNA and the use of DT40 chicken B cell lines expressing CD300a and deficient in several phosphatases revealed that SHP-1, but not SHP-2 or the src homology 2 domain containing inositol 5' phosphatase SHIP, was utilized by CD300a for its inhibitory activity. These studies provide new insights into the function of CD300a in tuning T and B cell responses.

Non-Small Cell Lung Cancer Cells Expressing CD44 Are Enriched for Stem Cell-Like Properties

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Leung, Elaine Lai-Han; Fiscus, Ronald R.; Tung, James W.; Tin, Vicky Pui-Chi; Cheng, Lik Cheung; Sihoe, Alan Dart-Loon; Fink, Louis M.; Ma, Yupo; Wong, Maria Pik

2010-01-01

Background The cancer stem cell theory hypothesizes that cancers are perpetuated by cancer stem cells (CSC) or tumor initiating cells (TIC) possessing self-renewal and other stem cell-like properties while differentiated non-stem/initiating cells have a finite life span. To investigate whether the hypothesis is applicable to lung cancer, identification of lung CSC and demonstration of these capacities is essential. Methodology/Principal Finding The expression profiles of five stem cell markers (CD34, CD44, CD133, BMI1 and OCT4) were screened by flow cytometry in 10 lung cancer cell lines. CD44 was further investigated by testing for in vitro and in vivo tumorigenecity. Formation of spheroid bodies and in vivo tumor initiation ability were demonstrated in CD44+ cells of 4 cell lines. Serial in vivo tumor transplantability in nude mice was demonstrated using H1299 cell line. The primary xenografts initiated from CD44+ cells consisted of mixed CD44+ and CD44− cells in similar ratio as the parental H1299 cell line, supporting in vivo differentiation. Semi-quantitative Real-Time PCR (RT-PCR) showed that both freshly sorted CD44+ and CD44+ cells derived from CD44+-initiated tumors expressed the pluripotency genes OCT4/POU5F1, NANOG, SOX2. These stemness markers were not expressed by CD44− cells. Furthermore, freshly sorted CD44+ cells were more resistant to cisplatin treatment with lower apoptosis levels than CD44− cells. Immunohistochemical analysis of 141 resected non-small cell lung cancers showed tumor cell expression of CD44 in 50.4% of tumors while no CD34, and CD133 expression was observed in tumor cells. CD44 expression was associated with squamous cell carcinoma but unexpectedly, a longer survival was observed in CD44-expressing adenocarcinomas. Conclusion/Significance Overall, our results demonstrated that stem cell-like properties are enriched in CD44-expressing subpopulations of some lung cancer cell lines. Further investigation is required to clarify

A+-Helix of Protein C Inhibitor (PCI) Is a Cell-penetrating Peptide That Mediates Cell Membrane Permeation of PCI*

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Yang, Hanjiang; Wahlmüller, Felix Christof; Sarg, Bettina; Furtmüller, Margareta; Geiger, Margarethe

2015-01-01

Protein C inhibitor (PCI) is a serpin with broad protease reactivity. It binds glycosaminoglycans and certain phospholipids that can modulate its inhibitory activity. PCI can penetrate through cellular membranes via binding to phosphatidylethanolamine. The exact mechanism of PCI internalization and the intracellular role of the serpin are not well understood. Here we showed that testisin, a glycosylphosphatidylinositol-anchored serine protease, cleaved human PCI and mouse PCI (mPCI) at their reactive sites as well as at sites close to their N terminus. This cleavage was observed not only with testisin in solution but also with cell membrane-anchored testisin on U937 cells. The cleavage close to the N terminus released peptides rich in basic amino acids. Synthetic peptides corresponding to the released peptides of human PCI (His1–Arg11) and mPCI (Arg1–Ala18) functioned as cell-penetrating peptides. Because intact mPCI but not testisin-cleaved mPCI was internalized by Jurkat T cells, a truncated mPCI mimicking testisin-cleaved mPCI was created. The truncated mPCI lacking 18 amino acids at the N terminus was not taken up by Jurkat T cells. Therefore our model suggests that testisin or other proteases could regulate the internalization of PCI by removing its N terminus. This may represent one of the mechanisms regulating the intracellular functions of PCI. PMID:25488662

Ligation of major histocompatibility complex class I antigens (MHC-I) prevents apoptosis induced by Fas or SAPK/JNK activation in T-lymphoma cells

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Lamberth, K; Claesson, M H

2001-01-01

Early apoptosis in Jurkat T-lymphoma cells was induced by agonistic anti-Fas Ab or by anisomycin which activates the stress kinases SAPK/JNK. Apoptosis was inhibited by ligation of major histocompatibility complex class I antigens (MHC-I). MHC-I ligation induced upregulation of the anti......-apoptotic Bcl-2 protein and stabilized the mitochondrial membrane potential (Deltapsim). MHC-I ligation also prevented downregulation of Bcl-2 and destabilization of Deltapsim induced by anti-Fas Ab treatment or anisomycin exposure. Studies on three different Jurkat cell mutants deficient for src p56(lck), ZAP......-70 kinase, or TCR/CD3 gamma-chain showed that the cells undergo apoptosis after Fas ligation. Anisomycin exposure induced apoptosis in the src p56(lck)-deficient cell line but not in the two other mutant cell lines. Simultaneous cross-linking of MHC-I and Fas ligation inhibited apoptosis in the ZAP...

Tenofovir alafenamide (TAF) does not deplete mitochondrial DNA in human T-cell lines at intracellular concentrations exceeding clinically relevant drug exposures.

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Stray, Kirsten M; Park, Yeojin; Babusis, Darius; Callebaut, Christian; Cihlar, Tomas; Ray, Adrian S; Perron, Michel

2017-04-01

HIV-infected patients treated with certain nucleoside reverse transcriptase inhibitors (NRTIs) have experienced adverse effects due to drug-related mitochondrial toxicity. Tenofovir alafenamide (TAF) is a novel prodrug of the NRTI tenofovir (TFV) with an improved safety profile compared to tenofovir disoproxil fumarate (TDF). Prior in vitro studies have demonstrated that the parent nucleotide TFV has no significant effects on mtDNA synthesis. This study investigated whether clinically relevant TAF and TDF exposures affect mtDNA content in human lymphocytes. First, activated or resting peripheral blood mononuclear cells (PBMCs), as well as MT-2 and Jurkat T-cell lines, were continuously treated with ddC for 10 days to establish their susceptibility to mtDNA depletion. PBMCs had low sensitivity to NRTI-mediated mtDNA depletion in vitro. In contrast, ddC treatment of rapidly dividing MT-2 and Jurkat cells resulted in a dose-dependent decrease in mtDNA. Therefore, these two T-cell lines were selected for evaluating TAF and TDF treatment effects. MT-2 and Jurkat cells were pulse-treated with TAF or TDF every 24 h for 10 days to mimic pharmacologically relevant drug exposures. Pulse treatment of cells with 3.3 μM TAF or 1.1 μM TDF for 10 days resulted in 2- to 7-fold greater steady-state intracellular TFV-diphosphate (TFV-DP) levels than those observed clinically in TAF- or TDF-treated patients. At these concentrations, no significant TAF- (106.7% and 84.1% of control; p = 0.77 and 0.12 for MT-2 and Jurkat, respectively) or TDF- (100.6% and 91.0% of control; p = 0.91 and 0.37, respectively) associated reduction in mtDNA content was observed compared with untreated control cells. This study demonstrates that, despite delivering higher intracellular levels of TFV-DP than TDF, TAF does not inhibit mtDNA synthesis in vitro at concentrations exceeding the clinically relevant intracellular drug exposures. Thus, TAF has a low potential for mitochondrial toxicity in

CNPase Expression in Olfactory Ensheathing Cells

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Christine Radtke

2011-01-01

Full Text Available A large body of work supports the proposal that transplantation of olfactory ensheathing cells (OECs into nerve or spinal cord injuries can promote axonal regeneration and remyelination. Yet, some investigators have questioned whether the transplanted OECs associate with axons and form peripheral myelin, or if they recruit endogenous Schwann cells that form myelin. Olfactory bulbs from transgenic mice expressing the enhanced green fluorescent protein (eGFP under the control of the 2-3-cyclic nucleotide 3-phosphodiesterase (CNPase promoter were studied. CNPase is expressed in myelin-forming cells throughout their lineage. We examined CNPase expression in both in situ in the olfactory bulb and in vitro to determine if OECs express CNPase commensurate with their myelination potential. eGFP was observed in the outer nerve layer of the olfactory bulb. Dissociated OECs maintained in culture had both intense eGFP expression and CNPase immunostaining. Transplantation of OECs into transected peripheral nerve longitudinally associated with the regenerated axons. These data indicate that OECs in the outer nerve layer of the olfactory bulb of CNPase transgenic mice express CNPase. Thus, while OECs do not normally form myelin on olfactory nerve axons, their expression of CNPase is commensurate with their potential to form myelin when transplanted into injured peripheral nerve.

Foxl1-Expressing Mesenchymal Cells Constitute the Intestinal Stem Cell NicheSummary

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Reina Aoki

2016-03-01

Full Text Available Background & Aims: Intestinal epithelial stem cells that express leucine-rich repeat-containing G-protein coupled receptor 5 (Lgr5 and/or B cell specific Moloney murine leukemia virus integration site 1 (Bmi1 continuously replicate and generate differentiated cells throughout life. Previously, Paneth cells were suggested to constitute an epithelium-intrinsic niche that regulates the behavior of these stem cells. However, ablating Paneth cells has no effect on the maintenance of functional stem cells. Here, we show definitively that a small subset of mesenchymal subepithelial cells expressing the winged-helix transcription factor forkhead box l1 (Foxl1 are a critical component of the intestinal stem cell niche. Methods: We genetically ablated Foxl1+ mesenchymal cells in adult mice using 2 separate models by expressing either the human or simian diphtheria toxin receptor under Foxl1 promoter control. Conclusions: Killing Foxl1+ cells by diphtheria toxin administration led to an abrupt cessation of proliferation of both epithelial stem- and transit-amplifying progenitor cell populations that was associated with a loss of active Wnt signaling to the intestinal epithelium. Therefore, Foxl1-expressing mesenchymal cells constitute the fundamental niche for intestinal stem cells. Keywords: Intestinal Stem Cell Niche, Wnt, Mesenchyme

Molecular pathway profiling of T lymphocyte signal transduction pathways; Th1 and Th2 genomic fingerprints are defined by TCR and CD28-mediated signaling

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Smeets Ruben L

2012-03-01

Full Text Available Abstract Background T lymphocytes are orchestrators of adaptive immunity. Naïve T cells may differentiate into Th1, Th2, Th17 or iTreg phenotypes, depending on environmental co-stimulatory signals. To identify genes and pathways involved in differentiation of Jurkat T cells towards Th1 and Th2 subtypes we performed comprehensive transcriptome analyses of Jurkat T cells stimulated with various stimuli and pathway inhibitors. Results from these experiments were validated in a human experimental setting using whole blood and purified CD4+ Tcells. Results Calcium-dependent activation of T cells using CD3/CD28 and PMA/CD3 stimulation induced a Th1 expression profile reflected by increased expression of T-bet, RUNX3, IL-2, and IFNγ, whereas calcium-independent activation via PMA/CD28 induced a Th2 expression profile which included GATA3, RXRA, CCL1 and Itk. Knock down with siRNA and gene expression profiling in the presence of selective kinase inhibitors showed that proximal kinases Lck and PKCθ are crucial signaling hubs during T helper cell activation, revealing a clear role for Lck in Th1 development and for PKCθ in both Th1 and Th2 development. Medial signaling via MAPkinases appeared to be less important in these pathways, since specific inhibitors of these kinases displayed a minor effect on gene expression. Translation towards a primary, whole blood setting and purified human CD4+ T cells revealed that PMA/CD3 stimulation induced a more pronounced Th1 specific, Lck and PKCθ dependent IFNγ production, whereas PMA/CD28 induced Th2 specific IL-5 and IL-13 production, independent of Lck activation. PMA/CD3-mediated skewing towards a Th1 phenotype was also reflected in mRNA expression of the master transcription factor Tbet, whereas PMA/CD28-mediated stimulation enhanced GATA3 mRNA expression in primary human CD4+ Tcells. Conclusions This study identifies stimulatory pathways and gene expression profiles for in vitro skewing of T helper cell

Rethinking cell-cycle-dependent gene expression in Schizosaccharomyces pombe.

Science.gov (United States)

Cooper, Stephen

2017-11-01

Three studies of gene expression during the division cycle of Schizosaccharomyces pombe led to the proposal that a large number of genes are expressed at particular times during the S. pombe cell cycle. Yet only a small fraction of genes proposed to be expressed in a cell-cycle-dependent manner are reproducible in all three published studies. In addition to reproducibility problems, questions about expression amplitudes, cell-cycle timing of expression, synchronization artifacts, and the problem with methods for synchronizing cells must be considered. These problems and complications prompt the idea that caution should be used before accepting the conclusion that there are a large number of genes expressed in a cell-cycle-dependent manner in S. pombe.

Glutathione S-transferase expression and isoenzyme composition during cell differentiation of Caco-2 cells

International Nuclear Information System (INIS)

Scharmach, E.; Hessel, S.; Niemann, B.; Lampen, A.

2009-01-01

The human colon adenocarcinoma cell line Caco-2 is frequently used to study human intestinal metabolism and transport of xenobiotica. Previous studies have shown that both Caco-2 cells and human colon cells constitutively express the multigene family of detoxifying enzymes glutathione S-transferases (GSTs), particularly GST alpha and GST pi. GSTs may play a fundamental role in the molecular interplay between phase I, II enzymes and ABC-transporters. The gut fermentation product, butyrate, can modulate the potential for detoxification. The aim of this study was to investigate the basal expression of further cytosolic GSTs in Caco-2 cells during cell differentiation. In addition, a comparison was made with expression levels in MCF-7 and HepG2, two other cell types with barrier functions. Finally, the butyrate-mediated modulation of gene and protein expression was determined by real time PCR and western blot analysis. In Caco-2, gene and protein expression levels of GST alpha increased during cell differentiation. High levels of GSTO1 and GSTP1 were constantly expressed. No expression of GSTM5 and GSTT1 was detected. HepG2 expressed GSTO1 and MCF-7 GSTZ1 most intensively. No expression of GSTA5, GSTM5, or GSTP1 was detected in either cell. Incubation of Caco-2 cells with butyrate (5 mM) significantly induced GSTA1 and GSTM2 in proliferating Caco-2 cells. In differentiated cells, butyrate tended to increase GSTO1 and GSTP1. The results of this study show that a differentiation-dependent expression of GSTs in Caco-2 cells may reflect the in vivo situation and indicate the potential of butyrate to modify intestinal metabolism. GSTA1-A4 have been identified as good markers for cell differentiation. The Caco-2 cell line is a useful model for assessing the potential of food-related substances to modulate the GST expression pattern.

Glutathione S-transferase expression and isoenzyme composition during cell differentiation of Caco-2 cells.

Science.gov (United States)

Scharmach, E; Hessel, S; Niemann, B; Lampen, A

2009-11-30

The human colon adenocarcinoma cell line Caco-2 is frequently used to study human intestinal metabolism and transport of xenobiotica. Previous studies have shown that both Caco-2 cells and human colon cells constitutively express the multigene family of detoxifying enzymes glutathione S-transferases (GSTs), particularly GST alpha and GST pi. GSTs may play a fundamental role in the molecular interplay between phase I, II enzymes and ABC-transporters. The gut fermentation product, butyrate, can modulate the potential for detoxification. The aim of this study was to investigate the basal expression of further cytosolic GSTs in Caco-2 cells during cell differentiation. In addition, a comparison was made with expression levels in MCF-7 and HepG2, two other cell types with barrier functions. Finally, the butyrate-mediated modulation of gene and protein expression was determined by real time PCR and western blot analysis. In Caco-2, gene and protein expression levels of GST alpha increased during cell differentiation. High levels of GSTO1 and GSTP1 were constantly expressed. No expression of GSTM5 and GSTT1 was detected. HepG2 expressed GSTO1 and MCF-7 GSTZ1 most intensively. No expression of GSTA5, GSTM5, or GSTP1 was detected in either cell. Incubation of Caco-2 cells with butyrate (5 mM) significantly induced GSTA1 and GSTM2 in proliferating Caco-2 cells. In differentiated cells, butyrate tended to increase GSTO1 and GSTP1. The results of this study show that a differentiation-dependent expression of GSTs in Caco-2 cells may reflect the in vivo situation and indicate the potential of butyrate to modify intestinal metabolism. GSTA1-A4 have been identified as good markers for cell differentiation. The Caco-2 cell line is a useful model for assessing the potential of food-related substances to modulate the GST expression pattern.

Norepinephrine and Epinephrine Enhanced the Infectivity of Enterovirus 71.

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Yu-Ting Liao

Full Text Available Enterovirus 71 (EV71 infections may be associated with neurological complications, including brainstem encephalitis (BE. Severe EV71 BE may be complicated with autonomic nervous system (ANS dysregulation and/or pulmonary edema (PE. ANS dysregulation is related to the overactivation of the sympathetic nervous system, which results from catecholamine release.The aims of this study were to explore the effects of catecholamines on severe EV71 infection and to investigate the changes in the percentages of EV71-infected cells, virus titer, and cytokine production on the involvement of catecholamines.Plasma levels of norepinephrine (NE and epinephrine (EP in EV71-infected patients were measured using an enzyme-linked immunoassay. The expression of adrenergic receptors (ADRs on RD, A549, SK-N-SH, THP-1, Jurkat and human peripheral blood mononuclear cells (hPBMCs were detected using flow cytometry. The percentages of EV71-infected cells, virus titer, and cytokine production were investigated after treatment with NE and EP.The plasma levels of NE and EP were significantly higher in EV71-infected patients with ANS dysregulation and PE than in controls. Both α1A- and β2-ADRs were expressed on A549, RD, SK-N-SH, HL-60, THP-1, Jurkat cells and hPBMCs. NE treatment elevated the percentages of EV71-infected cells to 62.9% and 22.7% in THP-1 and Jurkat cells, respectively. Via treatment with EP, the percentages of EV71-infected cells were increased to 64.6% and 26.9% in THP-1 and Jurkat cells. The percentage of EV71-infected cells increased upon NE or EP treatment while the α- and β-blockers reduced the percentages of EV71-infected cells with NE or EP treatment. At least two-fold increase in virus titer was observed in EV71-infected A549, SK-N-SH and hPBMCs after treatment with NE or EP. IL-6 production was enhanced in EV71-infected hPBMCs at a concentration of 102 pg/mL NE.The plasma levels of NE and EP elevated in EV71-infected patients with ANS

Norepinephrine and Epinephrine Enhanced the Infectivity of Enterovirus 71.

Science.gov (United States)

Liao, Yu-Ting; Wang, Shih-Min; Wang, Jen-Ren; Yu, Chun-Keung; Liu, Ching-Chuan

2015-01-01

Enterovirus 71 (EV71) infections may be associated with neurological complications, including brainstem encephalitis (BE). Severe EV71 BE may be complicated with autonomic nervous system (ANS) dysregulation and/or pulmonary edema (PE). ANS dysregulation is related to the overactivation of the sympathetic nervous system, which results from catecholamine release. The aims of this study were to explore the effects of catecholamines on severe EV71 infection and to investigate the changes in the percentages of EV71-infected cells, virus titer, and cytokine production on the involvement of catecholamines. Plasma levels of norepinephrine (NE) and epinephrine (EP) in EV71-infected patients were measured using an enzyme-linked immunoassay. The expression of adrenergic receptors (ADRs) on RD, A549, SK-N-SH, THP-1, Jurkat and human peripheral blood mononuclear cells (hPBMCs) were detected using flow cytometry. The percentages of EV71-infected cells, virus titer, and cytokine production were investigated after treatment with NE and EP. The plasma levels of NE and EP were significantly higher in EV71-infected patients with ANS dysregulation and PE than in controls. Both α1A- and β2-ADRs were expressed on A549, RD, SK-N-SH, HL-60, THP-1, Jurkat cells and hPBMCs. NE treatment elevated the percentages of EV71-infected cells to 62.9% and 22.7% in THP-1 and Jurkat cells, respectively. Via treatment with EP, the percentages of EV71-infected cells were increased to 64.6% and 26.9% in THP-1 and Jurkat cells. The percentage of EV71-infected cells increased upon NE or EP treatment while the α- and β-blockers reduced the percentages of EV71-infected cells with NE or EP treatment. At least two-fold increase in virus titer was observed in EV71-infected A549, SK-N-SH and hPBMCs after treatment with NE or EP. IL-6 production was enhanced in EV71-infected hPBMCs at a concentration of 102 pg/mL NE. The plasma levels of NE and EP elevated in EV71-infected patients with ANS dysregulation and

Oncomirs Expression Profiling in Uterine Leiomyosarcoma Cells

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Bruna Cristine de Almeida

2017-12-01

Full Text Available MicroRNAs (miRNAs are small non-coding RNAs that act as regulators of gene expression at the post-transcriptional level. They play a key role in several biological processes. Their abnormal expression may lead to malignant cell transformation. This study aimed to evaluate the expression profile of 84 miRNAs involved in tumorigenesis in immortalized cells of myometrium (MM, uterine leiomyoma (ULM, and uterine leiomyosarcoma (ULMS. Specific cell lines were cultured and qRT-PCR was performed. Thirteen miRNAs presented different expression profiles in ULM and the same thirteen in ULMS compared to MM. Eight miRNAs were overexpressed, and five were underexpressed in ULM. In ULMS cells, five miRNAs exhibited an overexpression and eight were down-regulated. Six miRNAs (miR-1-3p, miR-130b-3p, miR-140-5p, miR-202-3p, miR-205-5p, and miR-7-5p presented a similar expression pattern in cell lines compared to patient samples. Of these, only three miRNAs showed significant expression in ULM (miR-1-3p, miR-140-5p, and miR-7-5p and ULMS (miR-1-3p, miR-202-3p, and miR-7-5p. Our preliminary approach identified 24 oncomirs with an altered expression profile in ULM and ULMS cells. We identified four differentially expressed miRNAs with the same profile when compared with patients’ samples, which strongly interacted with relevant genes, including apoptosis regulator (BCL2, epidermal growth factor receptor (EGFR, vascular endothelial growth factor A (VEGFA, insulin like growth factor 1 receptor (IGF1R,serine/threonine kinase (RAF1, receptor tyrosine kinase (MET, and bHLH transcription factor (MYCN. This led to alterations in their mRNA-target.

Automatic Control of Gene Expression in Mammalian Cells.

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Fracassi, Chiara; Postiglione, Lorena; Fiore, Gianfranco; di Bernardo, Diego

2016-04-15

Automatic control of gene expression in living cells is paramount importance to characterize both endogenous gene regulatory networks and synthetic circuits. In addition, such a technology can be used to maintain the expression of synthetic circuit components in an optimal range in order to ensure reliable performance. Here we present a microfluidics-based method to automatically control gene expression from the tetracycline-inducible promoter in mammalian cells in real time. Our approach is based on the negative-feedback control engineering paradigm. We validated our method in a monoclonal population of cells constitutively expressing a fluorescent reporter protein (d2EYFP) downstream of a minimal CMV promoter with seven tet-responsive operator motifs (CMV-TET). These cells also constitutively express the tetracycline transactivator protein (tTA). In cells grown in standard growth medium, tTA is able to bind the CMV-TET promoter, causing d2EYFP to be maximally expressed. Upon addition of tetracycline to the culture medium, tTA detaches from the CMV-TET promoter, thus preventing d2EYFP expression. We tested two different model-independent control algorithms (relay and proportional-integral (PI)) to force a monoclonal population of cells to express an intermediate level of d2EYFP equal to 50% of its maximum expression level for up to 3500 min. The control input is either tetracycline-rich or standard growth medium. We demonstrated that both the relay and PI controllers can regulate gene expression at the desired level, despite oscillations (dampened in the case of the PI controller) around the chosen set point.

Altered T-cell responses by the periodontal pathogen Porphyromonas gingivalis.

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Hazem Khalaf

Full Text Available Several studies support an association between the chronic inflammatory diseases periodontitis and atherosclerosis with a crucial role for the periodontal pathogen Porphyromonas gingivalis. However, the interplay between this pathogen and the adaptive immune system, including T-cells, is sparsely investigated. Here we used Jurkat T-cells to determine the effects of P. gingivalis on T-cell-mediated adaptive immune responses. We show that viable P. gingivalis targets IL-2 expression at the protein level. Initial cellular events, including ROS production and [Ca(2+](i, were elevated in response to P. gingivalis, but AP-1 and NF-κB activity dropped below basal levels and T-cells were unable to sustain stable IL-2 accumulation. IL-2 was partially restored by Leupeptin, but not by Cathepsin B Inhibitor, indicating an involvement of Rgp proteinases in the suppression of IL-2 accumulation. This was further confirmed by purified Rgp that caused a dose-dependent decrease in IL-2 levels. These results provide new insights of how this periodontal pathogen evades the host adaptive immune system by inhibiting IL-2 accumulation and thus attenuating T-cell proliferation and cellular communication.

Expression of MIF and CD74 in leukemic cell lines: correlation to DR expression destiny.

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Georgouli, Mirella; Papadimitriou, Lina; Glymenaki, Maria; Patsaki, Valia; Athanassakis, Irene

2016-06-01

Invariant chain (Ii) or CD74 is a non-polymorphic glycoprotein, which apart from its role as a chaperone dedicated to MHCII molecules, is known to be a high-affinity receptor for macrophage migration inhibitory factor (MIF). The present study aimed to define the roles of CD74 and MIF in the immune surveillance escape process. Towards this direction, the cell lines HL-60, Raji, K562 and primary pre-B leukemic cells were examined for expression and secretion of MIF. Flow cytometry analysis detected high levels of MIF and intracellular/membrane CD74 expression in all leukemic cells tested, while MIF secretion was shown to be inversely proportional to intracellular HLA-DR (DR) expression. In the MHCII-negative cells, IFN-γ increased MIF expression and induced its secretion in HL-60 and K562 cells, respectively. In K562 cells, CD74 (Iip33Iip35) was shown to co-precipitate with HLA-DOβ (DOβ), inhibiting thus MIF or DR binding. Induced expression of DOα in K562 (DOα-DOβ+) cells in different transfection combinations decreased MIF expression and secretion, while increasing surface DR expression. Thus, MIF could indeed be part of the antigen presentation process.

Impaired cell surface expression of HLA-B antigens on mesenchymal stem cells and muscle cell progenitors

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Isa, Adiba; Nehlin, Jan; Sabir, Hardee Jawad

2010-01-01

HLA class-I expression is weak in embryonic stem cells but increases rapidly during lineage progression. It is unknown whether all three classical HLA class-I antigens follow the same developmental program. In the present study, we investigated allele-specific expression of HLA-A, -B, and -C...... at the mRNA and protein levels on human mesenchymal stem cells from bone marrow and adipose tissue as well as striated muscle satellite cells and lymphocytes. Using multicolour flow cytometry, we found high cell surface expression of HLA-A on all stem cells and PBMC examined. Surprisingly, HLA-B was either...... undetectable or very weakly expressed on all stem cells protecting them from complement-dependent cytotoxicity (CDC) using relevant human anti-B and anti-Cw sera. IFNgamma stimulation for 48-72 h was required to induce full HLA-B protein expression. Quantitative real-time RT-PCR showed that IFNgamma induced...

CD40 expression in Wehi-164 cell line.

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Karimi, Mohammad Hossein; Ebadi, Padideh; Pourfathollah, Ali Akbar; Soheili, Zahra Soheila; Moazzeni, Seyed Mohammad

2010-07-01

CD40-CD154 interaction is an important process for cellular and humoral immunity regulation and can be effective in the body's defense against tumors. In the present study, we evaluated the expression of CD40 in Wehi-164 cell line. CD40 expressions on the cell surface and in the cytoplasm were assessed by flow cytometry and intracellular staining assay, respectively. Also, the mRNA expression was identified by real time-PCR. The obtained results showed the high mRNA and cytoplasmic protein expression of CD40 but no surface expression. These results suggest that the Wehi-164 cell line down regulates expression of CD40 on the surface for evasion of immune system.

HBx induced AFP receptor expressed to activate PI3K/AKT signal to promote expression of Src in liver cells and hepatoma cells

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Zhu, Mingyue; Guo, Junli; Li, Wei; Xia, Hua; Lu, Yan; Dong, Xu; Chen, Yi; Xie, Xieju; Fu, Shigan; Li, Mengsen

2015-01-01

Hepatitis B virus (HBV)-X protein(HBx) is a transactivator of host several cellular genes including alpha-fetoprotein(AFP) and AFP receptor(AFPR) which contributes to HBV-associated tumor development. The expression of AFP/AFPR are correlated with hepatocellular carcinoma(HCC)-initial cells. But the role of AFP and AFPR in promoting occurrence of HBV-related HCC were still unclear. A total of 71 clinical patients’ liver specimens, normal human liver cells L-02 and HCC cell lines, PLC/PRF/5 were selected for analyzing the effects of HBx on expression of AFP, AFPR and Src. The expression of goal proteins were detected by Immunohistochemical stained and Western blotting; HBx-expressed vectors were constructed and transfected into L-02 cells, laser confocal microscopy was applied to observe expression and location of AFP, AFPR and Src in the normal liver cells and HCC cells, soft agar colony formation assay was used to observe colonies formed of the cells. We confirmed HBx gives preference to promote the expression of AFP and AFPR; HBx priors to up-regulate the expression of AFPR and AFP in L-02 cells and in normal liver specimens; AFPR signal been able to stimulate Src expression. The results also indicated that phosphatidylinositol 3-kinase(PI3K) inhibitors Ly294002 and GDC0941 effectively suppress AFPR mediated up-regulation expression of Src in AFPR positive HCC lines. HBx priors to drive the expression of AFP and AFPR to promote expression of Src in normal liver cells and hepatoma cells; AFP and AFPR maybe play pivotal role in HBV-related hepatocarcinogenesis; Targeting AFPR is an available therapeutic strategy of HCC. The online version of this article (doi:10.1186/s12885-015-1384-9) contains supplementary material, which is available to authorized users

Expression of myc family oncoproteins in small-cell lung-cancer cell lines and xenografts

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Rygaard, K; Vindeløv, L L; Spang-Thomsen, M

1993-01-01

A number of genes have altered activity in small-cell lung cancer (SCLC), but especially genes of the myc family (c-myc, L-myc and N-myc) are expressed at high levels in SCLC. Most studies have explored expression at the mRNA level, whereas studies of myc family oncoprotein expression are sparse....... WE examined the expression of myc proto-oncogenes at the mRNA and protein level in 23 cell lines or xenografts. In the cell lines, the doubling time and the cell-cycle distribution, as determined by flow-cytometric DNA analysis, were examined to establish whether the level of myc......-myc. In general, the level of expression of c-myc and N-myc was similar at the mRNA and the protein level. Expression of c-myc was positively correlated with the proliferative index (sum of S and G2+M phases) of cell lines, but not with the population doubling time. In general, L-myc-expressing cell lines had...

Hemoglobin Expression in Nonerythroid Cells: Novel or Ubiquitous?

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Debarchana Saha

2014-01-01

Full Text Available Hemoglobin (Hb is a major protein involved in transport of oxygen (O2. Red blood cells (RBCs contain maximum amount of Hb and because of their unique structure and plasticity they transport O2 to various tissues of the body at an optimal concentration. Recently, it has been reported that, apart from RBCs, Hb is also expressed by nonerythroid cells such as epithelial cells of different origin. The cells expressing Hb are from the tissues where maintenance of O2 homeostasis is of paramount importance. Hb expression has been observed in the epithelial cells from human tissues including lungs, neurons, retina, and endometrium. Our group has recently demonstrated that Hb is expressed by the cervicovaginal epithelial cells. We further showed that, apart from maintaining O2 homeostasis, Hb and the peptides derived from it play an indispensable role in the protection of vaginal epithelium by exhibiting antimicrobial activity. In this review, we discuss the significance of Hb expression in vaginal epithelial cells and its role in the recognition of pathogens thereby reducing the risk and/or severity of inflammation and/or infections and the possible mechanism by which Hb exhibits antimicrobial and antioxidative functions.

Prostate stromal cells express the progesterone receptor to control cancer cell mobility.

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Yu, Yue; Lee, Jennifer Suehyun; Xie, Ning; Li, Estelle; Hurtado-Coll, Antonio; Fazli, Ladan; Cox, Michael; Plymate, Stephen; Gleave, Martin; Dong, Xuesen

2014-01-01

Reciprocal interactions between epithelium and stroma play vital roles for prostate cancer development and progression. Enhanced secretions of cytokines and growth factors by cancer associated fibroblasts in prostate tumors create a favorable microenvironment for cancer cells to grow and metastasize. Our previous work showed that the progesterone receptor (PR) was expressed specifically in prostate stromal fibroblasts and smooth muscle cells. However, the expression levels of PR and its impact to tumor microenvironment in prostate tumors are poorly understood. Immunohistochemistry assays are applied to human prostate tissue biopsies. Cell migration, invasion and proliferation assays are performed using human prostate cells. Real-time PCR and ELISA are applied to measure gene expression at molecular levels. Immunohistochemistry assays showed that PR protein levels were decreased in cancer associated stroma when compared with paired normal prostate stroma. Using in vitro prostate stromal cell models, we showed that conditioned media collected from PR positive stromal cells inhibited prostate cancer cell migration and invasion, but had minor suppressive impacts on cancer cell proliferation. PR suppressed the secretion of stromal derived factor-1 (SDF-1) and interlukin-6 (IL-6) by stromal cells independent to PR ligands. Blocking PR expression by siRNA or supplementation of exogenous SDF-1 or IL-6 to conditioned media from PR positive stromal cells counteracted the inhibitory effects of PR to cancer cell migration and invasion. Decreased expression of the PR in cancer associated stroma may contribute to the elevated SDF-1 and IL-6 levels in prostate tumors and enhance prostate tumor progression.

Prostate stromal cells express the progesterone receptor to control cancer cell mobility.

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Yue Yu

Full Text Available Reciprocal interactions between epithelium and stroma play vital roles for prostate cancer development and progression. Enhanced secretions of cytokines and growth factors by cancer associated fibroblasts in prostate tumors create a favorable microenvironment for cancer cells to grow and metastasize. Our previous work showed that the progesterone receptor (PR was expressed specifically in prostate stromal fibroblasts and smooth muscle cells. However, the expression levels of PR and its impact to tumor microenvironment in prostate tumors are poorly understood.Immunohistochemistry assays are applied to human prostate tissue biopsies. Cell migration, invasion and proliferation assays are performed using human prostate cells. Real-time PCR and ELISA are applied to measure gene expression at molecular levels.Immunohistochemistry assays showed that PR protein levels were decreased in cancer associated stroma when compared with paired normal prostate stroma. Using in vitro prostate stromal cell models, we showed that conditioned media collected from PR positive stromal cells inhibited prostate cancer cell migration and invasion, but had minor suppressive impacts on cancer cell proliferation. PR suppressed the secretion of stromal derived factor-1 (SDF-1 and interlukin-6 (IL-6 by stromal cells independent to PR ligands. Blocking PR expression by siRNA or supplementation of exogenous SDF-1 or IL-6 to conditioned media from PR positive stromal cells counteracted the inhibitory effects of PR to cancer cell migration and invasion.Decreased expression of the PR in cancer associated stroma may contribute to the elevated SDF-1 and IL-6 levels in prostate tumors and enhance prostate tumor progression.

Expression and significance of Axin2 in pancreatic cancer cells

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ZHANG Tao

2016-05-01

Full Text Available ObjectiveTo investigate the expression of Axin2 in pancreatic cancer cells, and to observe the influence of Axin2 on the proliferation, invasion, and migration of human pancreatic cancer cells (PANC-1. MethodsQuantitative real-time PCR was used to measure the expression of Axin2 in pancreatic cancer cell lines with different invasive abilities (PANC-1, Mia PaCa-2, and BxPC-3 and immortalized normal pancreatic cells (H6C7. PANC-1 cells with low expression were transfected with over-expressed Axin2 plasmid by transient transfection. MTT assay, Transwell assay, and scratch assay were used to determine the proliferation, invasion, and migration of cells transfected with over-expressed Axin2. One-way analysis of variance was used for comparison between multiple groups, and SNK-q test was used for comparison between any two groups. ResultsThe relative expression levels of Axin2 in PANC-1, BxPC-3, Mia PaCa-2, and H6C7 cells were 0.13±0.01, 0.42±0.05, 0.24±0.011, and 1.00±0.00, respectively, and PANC-1 cells had the lowest expression level of Axin2, with significant differences compared with the other cells (all P＜0.05. When PANC-1 cells were transfected with over-expressed Axin2 plasmid, the cells in the over-expression group had a significant increase in the expression level of Axin2 compared with those in the blank group and the negative control group (both P＜0.05. Compared with those in the non-transfection group and the blank group, PANC-1 cells in the over-expression group showed significant reductions in the proliferation, invasion, and migration abilities. ConclusionThe expression of Axin2 is down-regulated in pancreatic cancer cell lines and decreases with the increasing invasion ability, suggesting the role of tumor suppressor gene. High expression of Axin2 can reduce the proliferation, invasion, and migration abilities of PANC-1 cells.

Advantages and Applications of CAR-Expressing Natural Killer Cells

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Wolfgang eGlienke

2015-02-01

Full Text Available In contrast to donor T cells, natural killer (NK cells are known to mediate anti-cancer effects without the risk of inducing graft-versus-host disease (GvHD. In order to improve cytotoxicity against resistant cancer cells, auspicious efforts have been made with chimeric antigen receptor (CAR expressing T- and NK cells. These CAR-modified cells express antigen receptors against tumor-associated surface antigens, thus redirecting the effector cells and enhancing tumor-specific immunosurveillance. However, many cancer antigens are also expressed on healthy tissues, potentially leading to off tumor/ on target toxicity by CAR-engineered cells. In order to control such potentially severe side effects, the insertion of suicide genes into CAR-modified effectors can provide a means for efficient depletion of these cells. While CAR-expressing T cells have entered successfully clinical trials, experience with CAR-engineered NK cells is mainly restricted to pre-clinical investigations and predominantly to NK cell lines. In this review we summarize the data on CAR expressing NK cells focusing on the possible advantage using these short-lived effector cells and discuss the necessity of suicide switches. Furthermore, we address the compliance of such modified NK cells with regulatory requirements as a new field in cellular immunotherapy.

Surfactant protein D delays Fas- and TRAIL-mediated extrinsic pathway of apoptosis in T cells.

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Djiadeu, Pascal; Kotra, Lakshmi P; Sweezey, Neil; Palaniyar, Nades

2017-05-01

Only a few extracellular soluble proteins are known to modulate apoptosis. We considered that surfactant-associated protein D (SP-D), an innate immune collectin present on many mucosal surfaces, could regulate apoptosis. Although SP-D is known to be important for immune cell homeostasis, whether SP-D affects apoptosis is unknown. In this study we aimed to determine the effects of SP-D on Jurkat T cells and human T cells dying by apoptosis. Here we show that SP-D binds to Jurkat T cells and delays the progression of Fas (CD95)-Fas ligand and TRAIL-TRAIL receptor induced, but not TNF-TNF receptor-mediated apoptosis. SP-D exerts its effects by reducing the activation of initiator caspase-8 and executioner caspase-3. SP-D also delays the surface exposure of phosphatidylserine. The effect of SP-D was ablated by the presence of caspase-8 inhibitor, but not by intrinsic pathway inhibitors. The binding ability of SP-D to dying cells decreases during the early stages of apoptosis, suggesting the release of apoptotic cell surface targets during apoptosis. SP-D also delays FasL-induced death of primary human T cells. SP-D delaying the progression of the extrinsic pathway of apoptosis could have important implications in regulating immune cell homeostasis at mucosal surfaces.

Suppression of LFA-1 expression by spermine is associated with enhanced methylation of ITGAL, the LFA-1 promoter area.

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Yoshihiko Kano

Full Text Available Spermine and spermidine, natural polyamines, suppress lymphocyte function-associated antigen 1 (LFA-1 expression and its associated cellular functions through mechanisms that remain unknown. Inhibition of ornithine decarboxylase, which is required for polyamine synthesis, in Jurkat cells by 3 mM D,L-alpha-difluoromethylornithine hydrochloride (DFMO significantly decreased spermine and spermidine concentrations and was associated with decreased DNA methyltransferase (Dnmt activity, enhanced demethylation of the LFA-1 gene (ITGAL promoter area, and increased CD11a expression. Supplementation with extracellular spermine (500 µM of cells pretreated with DFMO significantly increased polyamine concentrations, increased Dnmt activity, enhanced methylation of the ITGAL promoter, and decreased CD11a expression. It has been shown that changes in intracellular polyamine concentrations affect activities of -adenosyl-L-methionine-decaroboxylase, and, as a result, affect concentrations of the methyl group donor, S-adenosylmethionine (SAM, and of the competitive Dnmt inhibitor, decarboxylated SAM. Additional treatments designed to increase the amount of SAM and decrease the amount of decarboxylated SAM-such as treatment with methylglyoxal bis-guanylhydrazone (an inhibitor of S-adenosyl-L-methionine-decaroboxylase and SAM supplementation-successfully decreased CD11a expression. Western blot analyses revealed that neither DFMO nor spermine supplementation affected the amount of active Ras-proximate-1, a member of the Ras superfamily of small GTPases and a key protein for regulation of CD11a expression. The results of this study suggest that polyamine-induced suppression of LFA-1 expression occurs via enhanced methylation of ITGAL.

Glioblastoma formation from cell population depleted of Prominin1-expressing cells.

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Kenji Nishide

2009-08-01

Full Text Available Prominin1 (Prom1, also known as CD133 in human has been widely used as a marker for cancer stem cells (CSCs, which self-renew and are tumorigenic, in malignant tumors including glioblastoma multiforme (GBM. However, there is other evidence showing that Prom1-negative cancer cells also form tumors in vivo. Thus it remains controversial whether Prom1 is a bona fide marker for CSCs. To verify if Prom1-expressing cells are essential for tumorigenesis, we established a mouse line, whose Prom1-expressing cells can be eliminated conditionally by a Cre-inducible DTA gene on the Prom1 locus together with a tamoxifen-inducible CreER(TM, and generated glioma-initiating cells (GICs-LD by overexpressing both the SV40 Large T antigen and an oncogenic H-Ras(L61 in neural stem cells of the mouse line. We show here that the tamoxifen-treated GICs-LD (GICs-DTA form tumor-spheres in culture and transplantable GBM in vivo. Thus, our studies demonstrate that Prom1-expressing cells are dispensable for gliomagenesis in this mouse model.

Death Receptor-Induced Apoptosis Signalling Regulation by Ezrin Is Cell Type Dependent and Occurs in a DISC-Independent Manner in Colon Cancer Cells

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Iessi, Elisabetta; Zischler, Luciana; Etringer, Aurélie; Bergeret, Marion; Morlé, Aymeric; Jacquemin, Guillaume; Morizot, Alexandre; Shirley, Sarah; Lalaoui, Najoua; Elifio-Esposito, Selene L.; Fais, Stefano; Garrido, Carmen; Solary, Eric; Micheau, Olivier

2015-01-01

Ezrin belongs to the ERM (ezrin-radixin-moesin) protein family and has been demonstrated to regulate early steps of Fas receptor signalling in lymphoid cells, but its contribution to TRAIL-induced cell death regulation in adherent cancer cells remains unknown. In this study we report that regulation of FasL and TRAIL-induced cell death by ezrin is cell type dependant. Ezrin is a positive regulator of apoptosis in T-lymphoma cell line Jurkat, but a negative regulator in colon cancer cells. Using ezrin phosphorylation or actin-binding mutants, we provide evidence that negative regulation of death receptor-induced apoptosis by ezrin occurs in a cytoskeleton- and DISC-independent manner, in colon cancer cells. Remarkably, inhibition of apoptosis induced by these ligands was found to be tightly associated with regulation of ezrin phosphorylation on serine 66, the tumor suppressor gene WWOX and activation of PKA. Deficiency in WWOX expression in the liver cancer SK-HEP1 or the pancreatic Mia PaCa-2 cell lines as well as WWOX silencing or modulation of PKA activation by pharmacological regulators, in the colon cancer cell line SW480, abrogated regulation of TRAIL signalling by ezrin. Altogether our results show that death receptor pro-apoptotic signalling regulation by ezrin can occur downstream of the DISC in colon cancer cells. PMID:26010871

Death Receptor-Induced Apoptosis Signalling Regulation by Ezrin Is Cell Type Dependent and Occurs in a DISC-Independent Manner in Colon Cancer Cells.

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Elisabetta Iessi

Full Text Available Ezrin belongs to the ERM (ezrin-radixin-moesin protein family and has been demonstrated to regulate early steps of Fas receptor signalling in lymphoid cells, but its contribution to TRAIL-induced cell death regulation in adherent cancer cells remains unknown. In this study we report that regulation of FasL and TRAIL-induced cell death by ezrin is cell type dependant. Ezrin is a positive regulator of apoptosis in T-lymphoma cell line Jurkat, but a negative regulator in colon cancer cells. Using ezrin phosphorylation or actin-binding mutants, we provide evidence that negative regulation of death receptor-induced apoptosis by ezrin occurs in a cytoskeleton- and DISC-independent manner, in colon cancer cells. Remarkably, inhibition of apoptosis induced by these ligands was found to be tightly associated with regulation of ezrin phosphorylation on serine 66, the tumor suppressor gene WWOX and activation of PKA. Deficiency in WWOX expression in the liver cancer SK-HEP1 or the pancreatic Mia PaCa-2 cell lines as well as WWOX silencing or modulation of PKA activation by pharmacological regulators, in the colon cancer cell line SW480, abrogated regulation of TRAIL signalling by ezrin. Altogether our results show that death receptor pro-apoptotic signalling regulation by ezrin can occur downstream of the DISC in colon cancer cells.

Bifenthrin activates homotypic aggregation in human T-cell lines.

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Hoffman, Nataly; Tran, Van; Daniyan, Anthony; Ojugbele, Olutosin; Pryor, Stephen C; Bonventre, Josephine A; Flynn, Katherine; Weeks, Benjamin S

2006-03-01

Here, we addressed the concern that, despite the lack of overt toxicity, exposure to low levels of the common household pyrethroid pesticide, bifenthrin, could cause harm to the immune system. To do this, we measure the effect of bifenthrin on phytohemagglutinin (PHA) activation of homotypic aggregation in human T-cell lines. The human CD4+ H9, and Jurkat cell lines and the human promonocyte U937 cell line, were exposed to varying concentrations of bifenthrin. Cell viability was determined using the AlmarBlue Toxicity Assay. Concentrations of bifenthrin which did not reduce cell viability were determined and these concentrations were tested for the effect of bifenthrin on PHA-mediated homotypic aggregation. Blocking antibodies to ICAM and LFA-1 were used to disrupt aggregation and a nonspecific IgG was used as a control. Bifenthrin was found to be nontoxic at concentrations ranging from 10(-4) to 10(-13) M. Bifenthrin did not inhibit PHA induced cell aggregation in all cell lines tested. However, at 10(-4) M, bifenthrin to form aggregates stimulated homotypic aggregation in the H9 and Jurkat T-cell lines. The bifenthrin-induced aggregate formation, like that seen with PHA, was blocked by treating the cells with antibodies to either LFA-1 or ICAM. The results here show that bifenthrin activates T-cell function by stimulating ICAM/LFA-1 mediated homotypic aggregation. This data suggests that exposure to bifenthrin, even at "acceptable" limits, can increase the risk for and frequency of inflammatory responses and diseases such as asthma.

Chemical sporulation and germination: cytoprotective nanocoating of individual mammalian cells with a degradable tannic acid-FeIII complex

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Lee, Juno; Cho, Hyeoncheol; Choi, Jinsu; Kim, Doyeon; Hong, Daewha; Park, Ji Hun; Yang, Sung Ho; Choi, Insung S.

2015-11-01

Individual mammalian cells were coated with cytoprotective and degradable films by cytocompatible processes maintaining the cell viability. Three types of mammalian cells (HeLa, NIH 3T3, and Jurkat cells) were coated with a metal-organic complex of tannic acid (TA) and ferric ion, and the TA-FeIII nanocoat effectively protected the coated mammalian cells against UV-C irradiation and a toxic compound. More importantly, the cell proliferation was controlled by programmed formation and degradation of the TA-FeIII nanocoat, mimicking the sporulation and germination processes found in nature.Individual mammalian cells were coated with cytoprotective and degradable films by cytocompatible processes maintaining the cell viability. Three types of mammalian cells (HeLa, NIH 3T3, and Jurkat cells) were coated with a metal-organic complex of tannic acid (TA) and ferric ion, and the TA-FeIII nanocoat effectively protected the coated mammalian cells against UV-C irradiation and a toxic compound. More importantly, the cell proliferation was controlled by programmed formation and degradation of the TA-FeIII nanocoat, mimicking the sporulation and germination processes found in nature. Electronic supplementary information (ESI) available: Experimental details, LSCM images, and SEM and TEM images. See DOI: 10.1039/c5nr05573c

Vitamin K3 and vitamin C alone or in combination induced apoptosis in leukemia cells by a similar oxidative stress signalling mechanism.

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Bonilla-Porras, Angelica R; Jimenez-Del-Rio, Marlene; Velez-Pardo, Carlos

2011-06-10

Secondary therapy-related acute lymphoblastic leukemia might emerge following chemotherapy and/or radiotherapy for primary malignancies. Therefore, other alternatives should be pursued to treat leukemia. It is shown that vitamin K3- or vitamin C- induced apoptosis in leukemia cells by oxidative stress mechanism involving superoxide anion radical and hydrogen peroxide generation, activation of NF-κB, p53, c-Jun, protease caspase-3 activation and mitochondria depolarization leading to nuclei fragmentation. Cell death was more prominent when Jurkat and K562 cells are exposed to VC and VK3 in a ratio 1000:1 (10 mM: 10 μM) or 100:1 (300 μM: 3 μM), respectively. We provide for the first time in vitro evidence supporting a causative role for oxidative stress in VK3- and VC-induced apoptosis in Jurkat and K562 cells in a domino-like mechanism. Altogether these data suggest that VK3 and VC should be useful in the treatment of leukemia.

Geometry of the Gene Expression Space of Individual Cells.

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Yael Korem

2015-07-01

Full Text Available There is a revolution in the ability to analyze gene expression of single cells in a tissue. To understand this data we must comprehend how cells are distributed in a high-dimensional gene expression space. One open question is whether cell types form discrete clusters or whether gene expression forms a continuum of states. If such a continuum exists, what is its geometry? Recent theory on evolutionary trade-offs suggests that cells that need to perform multiple tasks are arranged in a polygon or polyhedron (line, triangle, tetrahedron and so on, generally called polytopes in gene expression space, whose vertices are the expression profiles optimal for each task. Here, we analyze single-cell data from human and mouse tissues profiled using a variety of single-cell technologies. We fit the data to shapes with different numbers of vertices, compute their statistical significance, and infer their tasks. We find cases in which single cells fill out a continuum of expression states within a polyhedron. This occurs in intestinal progenitor cells, which fill out a tetrahedron in gene expression space. The four vertices of this tetrahedron are each enriched with genes for a specific task related to stemness and early differentiation. A polyhedral continuum of states is also found in spleen dendritic cells, known to perform multiple immune tasks: cells fill out a tetrahedron whose vertices correspond to key tasks related to maturation, pathogen sensing and communication with lymphocytes. A mixture of continuum-like distributions and discrete clusters is found in other cell types, including bone marrow and differentiated intestinal crypt cells. This approach can be used to understand the geometry and biological tasks of a wide range of single-cell datasets. The present results suggest that the concept of cell type may be expanded. In addition to discreet clusters in gene-expression space, we suggest a new possibility: a continuum of states within a

CD133 expression in chemo-resistant Ewing sarcoma cells

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Kovar Heinrich

2010-03-01

Full Text Available Abstract Background Some human cancers demonstrate cellular hierarchies in which tumor-initiating cancer stem cells generate progeny cells with reduced tumorigenic potential. This cancer stem cell population is proposed to be a source of therapy-resistant and recurrent disease. Ewing sarcoma family tumors (ESFT are highly aggressive cancers in which drug-resistant, relapsed disease remains a significant clinical problem. Recently, the cell surface protein CD133 was identified as a putative marker of tumor-initiating cells in ESFT. We evaluated ESFT tumors and cell lines to determine if high levels of CD133 are associated with drug resistance. Methods Expression of the CD133-encoding PROM1 gene was determined by RT-PCR in ESFT tumors and cell lines. CD133 protein expression was assessed by western blot, FACS and/or immunostaining. Cell lines were FACS-sorted into CD133+ and CD133- fractions and proliferation, colony formation in soft agar, and in vivo tumorigenicity compared. Chemosensitivity was measured using MTS (3-(4,5-dimethylthiazol-2-yl-5-(3-carboxy-methoxyphenyl-2-(4-sulfophenyl-2H-tetrazolium assays. Results PROM1 expression was either absent or extremely low in most tumors. However, PROM1 was highly over-expressed in 4 of 48 cases. Two of the 4 patients with PROM1 over-expressing tumors rapidly succumbed to primary drug-resistant disease and two are long-term, event-free survivors. The expression of PROM1 in ESFT cell lines was similarly heterogeneous. The frequency of CD133+ cells ranged from 2-99% and, with one exception, no differences in the chemoresistance or tumorigenicity of CD133+ and CD133- cell fractions were detected. Importantly, however, the STA-ET-8.2 cell line was found to retain a cellular hierarchy in which relatively chemo-resistant, tumorigenic CD133+ cells gave rise to relatively chemo-sensitive, less tumorigenic, CD133- progeny. Conclusions Up to 10% of ESFT express high levels of PROM1. In some tumors and cell

B cell lymphomas express CX3CR1 a non-B cell lineage adhesion molecule

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Andreasson, U.; Ek, S.; Merz, H.

2008-01-01

normally is not expressed on B cells, is expressed both at the mRNA and protein level in several subtypes of lymphoma. CX3CR1 has also shown to be involved in the homing to specific tissues that express the ligand, CX3CL1, in breast and prostate cancer and may thus be involved in dissemination of lymphoma......To study the differential expression of cell membrane-bound receptors and their potential role in growth and/or survival of the tumor cells, highly purified follicular lymphoma cells were analyzed, using gene expression analysis, and compared to non-malignant B cell populations. Filtering...... the genome for overexpressed genes coding for cell membrane-bound proteins/receptors resulted in a hit list of 27 identified genes. Among these, we have focused on the aberrant over expression of CX3CR1, in different types of B cell lymphoma, as compared to non-malignant B cells. We show that CX3CR1, which...

Behavioral experience induces zif268 expression in mature granule cells but suppresses its expression in immature granule cells

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Kylie A. Huckleberry

2015-08-01

Full Text Available Thousands of neurons are born each day in the dentate gyrus (DG, but many of these cells die before reaching maturity. Both death and survival of adult-born neurons are regulated by neuronal activity in DG. The immediate-early gene (IEG zif268 is an important mediator of these effects, as its expression is induced by neural activity and knockout of zif268 impairs survival of adult-born neurons (Veyrac et al., 2013. Despite the apparent importance of zif268 for adult neurogenesis, its behavior-induced expression has not been fully characterized in adult-born neurons. Here we characterize behavior-evoked expression of zif268 in mature and newborn dentate granule cells (DGCs. In the general granule cell population, zif268 expression peaked 1 hour after novel environment exposure and returned to baseline by 8 hours post-exposure. However, in the doublecortin-positive (DCX+ immature neurons, zif268 expression was suppressed relative to home cage for at least 8 hours post-exposure. We next determined that exposure to water maze training, an enriched environment, or a novel environment caused approximately equal suppression of zif268 expression in DCX+ cells and approximately equal activation of zif268 in the general DGC population and in 6-week-old adult-born neurons. Finally, we asked whether zif268 suppression varied as a function of age within the DCX+ population, which ranges in age from 0 to approximately 4 weeks. Novel environment exposure had no significant effect on zif268 expression in 2- or 4-week-old BrdU-labeled neurons, but it significantly suppressed zif268 expression in 3-week-old neurons. In summary, behavioral experience transiently activated expression of zif268 in mature DGCs but caused a more long-lasting suppression of zif268 expression in immature, adult-born DGCs. We hypothesize that zif268 suppression inhibits memory-related synaptic plasticity in immature DGCs or mediates learning-induced apoptosis of immature adult

Human thymic epithelial cells express functional HLA-DP molecules

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Jørgensen, A; Röpke, C; Nielsen, M

1996-01-01

T lymphocytes, we examined whether human thymic epithelial cells (TEC) expressed HLA-DP molecules. We present evidence that TEC obtained from short time culture express low but significant levels of HLA-DP molecules. The expression of HLA-DP molecules was comparable to or higher than the expression...... of HLA-DP allospecific primed lymphocyte typing (PLT) CD4 T cell lines. IFN-gamma treatment strongly upregulated the HLA-DP allospecific PLT responses whereas other PLT responses remained largely unchanged. In conclusion, these data indicate that human thymus epithelial cells express significant levels...

Absence of annexin I expression in B-cell non-Hodgkin's lymphomas and cell lines

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Gopalakrishnan Velliyur K

2004-03-01

Full Text Available Abstract Background Annexin I, one of the 20 members of the annexin family of calcium and phospholipid-binding proteins, has been implicated in diverse biological processes including signal transduction, mediation of apoptosis and immunosuppression. Previous studies have shown increased annexin I expression in pancreatic and breast cancers, while it is absent in prostate and esophageal cancers. Results Data presented here show that annexin I mRNA and protein are undetectable in 10 out of 12 B-cell lymphoma cell lines examined. Southern blot analysis indicates that the annexin I gene is intact in B-cell lymphoma cell lines. Aberrant methylation was examined as a cause for lack of annexin I expression by treating cells 5-Aza-2-deoxycytidine. Reexpression of annexin I was observed after prolonged treatment with the demethylating agent indicating methylation may be one of the mechanisms of annexin I silencing. Treatment of Raji and OMA-BL-1 cells with lipopolysaccharide, an inflammation inducer, and with hydrogen peroxide, a promoter of oxidative stress, also failed to induce annexin I expression. Annexin I expression was examined in primary lymphoma tissues by immunohistochemistry and presence of annexin I in a subset of normal B-cells and absence of annexin I expression in the lymphoma tissues were observed. These results show that annexin I is expressed in normal B-cells, and its expression is lost in all primary B-cell lymphomas and 10 of 12 B-cell lymphoma cell lines. Conclusions Our results suggest that, similar to prostate and esophageal cancers, annexin I may be an endogenous suppressor of cancer development, and loss of annexin I may contribute to B-cell lymphoma development.

Novel method for isolation of murine clara cell secretory protein-expressing cells with traces of stemness.

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Xiao-Yang Wang

Full Text Available Clara cells are non-ciliated, secretory bronchiolar epithelial cells that serve to detoxify harmful inhaled substances. Clara cells also function as stem/progenitor cells for repair in the bronchioles. Clara cell secretory protein (CCSP is specifically expressed in pulmonary Clara cells and is widely used as a Clara cell marker. In addition CCSP promoter is commonly used to direct gene expression into the lung in transgenic models. The discovery of CCSP immunoreactivity in plasma membranes of airway lining cells prompted us to explore the possibility of enriching Clara cells by flow cytometry. We established a novel and simple method for the isolation of CCSP-expressing cell Clara cells using a combination of mechanical and enzymatic dissociation followed by flow cytometry sorting technology. We showed that ∼25% of dissociated cells from whole lung expressed CCSP. In the resulting preparation, up to 98% of cells expressed CCSP. Notably, we found that several common stem cell markers including CD44, CD133, Sca-1 and Sox2 were expressed in CCSP(+ cells. Moreover, CCSP(+ cells were able to form spheroid colonies in vitro with 0.97‰ efficiency. Parallel studies in vivo confirmed that a small population of CCSP(-expressing cells in mouse airways also demonstrates stem cell-like properties such as label retention and harboring rare bronchioalveolar stem cells (BASCs in terminal bronchioles (TBs. We conclude that CCSP(+ cells exhibit a number of stem cell-like features including stem cell marker expression, bronchosphere colony formation and self-renewal ability. Clara cell isolation by flow cytometry sorting is a useful method for investigating the function of primary Clara cells in stem cell research and mouse models.

Endo- and exocytic rate constants for spontaneous and protein kinase C-activated T cell receptor cycling

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Menné, Charlotte; Møller Sørensen, Tine; Siersma, Volkert

2002-01-01

To determine the rate constants of spontaneous and activated TCR cycling, we examined TCR endo- and exocytosis in the human T cell line Jurkat by three different methods. Using a simple kinetic model for TCR cycling and non-linear regression analyses, we found that the spontaneous endocytic rate...... constant of the TCR was low (approximately 0.012 min(-1)) whereas the spontaneous exocytic rate constant was similar to that of other cycling receptors (approximately 0.055 min(-1)). Following protein kinase C activation (PKC) the endocytic rate constant was increased tenfold (to approximately 0.128 min(-1......)) whereas the exocytic rate constant was unaffected. Thus, the TCR becomes a rapidly cycling receptor with kinetics similar to classical cycling receptors subsequent to PKC activation. This results in a reduction of the half-life of cell surface expressed TCR from approximately 58 to 6 min and allows rapid...

The Expression of BTS-2 Enhances Cell Growth and Invasiveness in Renal Cell Carcinoma.

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Pham, Quoc Thang; Oue, Naohide; Yamamoto, Yuji; Shigematsu, Yoshinori; Sekino, Yohei; Sakamoto, Naoya; Sentani, Kazuhiro; Uraoka, Naohiro; Tiwari, Mamata; Yasui, Wataru

2017-06-01

Renal cell carcinoma (RCC) is one of the most common types of cancer in developed countries. Bone marrow stromal cell antigen 2 (BST2) gene, which encodes BST2 transmembrane glycoprotein, is overexpressed in several cancer types. In the present study, we analyzed the expression and function of BST2 in RCC. BST2 expression was analyzed by immunohistochemistry in 123 RCC cases. RNA interference was used to inhibit BST2 expression in a RCC cell line. Immunohistochemical analysis showed that 32% of the 123 RCC cases were positive for BST2. BST2 expression was positively associated with tumour stage. Furthermore, BST2 expression was an independent predictor of survival in patients with RCC. BST2 siRNA-transfected Caki-1 cells displayed significantly reduced cell growth and invasive activity relative to negative control siRNA-transfected cells. These results suggest that BST2 plays an important role in the progression of RCC. Because BST2 is expressed on the cell membrane, BST2 is a good therapeutic target for RCC. Copyright© 2017, International Institute of Anticancer Research (Dr. George J. Delinasios), All rights reserved.

Efflux protein expression in human stem cell-derived retinal pigment epithelial cells.

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Kati Juuti-Uusitalo

Full Text Available Retinal pigment epithelial (RPE cells in the back of the eye nourish photoreceptor cells and form a selective barrier that influences drug transport from the blood to the photoreceptor cells. At the molecular level, ATP-dependent efflux transporters have a major role in drug delivery in human RPE. In this study, we assessed the relative expression of several ATP-dependent efflux transporter genes (MRP1, -2, -3, -4, -5, -6, p-gp, and BCRP, the protein expression and localization of MRP1, MRP4, and MRP5, and the functionality of MRP1 efflux pumps at different maturation stages of undifferentiated human embryonic stem cells (hESC and RPE derived from the hESC (hESC-RPE. Our findings revealed that the gene expression of ATP-dependent efflux transporters MRP1, -3, -4, -5, and p-gp fluctuated during hESC-RPE maturation from undifferentiated hESC to fusiform, epithelioid, and finally to cobblestone hESC-RPE. Epithelioid hESC-RPE had the highest expression of MRP1, -3, -4, and P-gp, whereas the most mature cobblestone hESC-RPE had the highest expression of MRP5 and MRP6. These findings indicate that a similar efflux protein profile is shared between hESC-RPE and the human RPE cell line, ARPE-19, and suggest that hESC-RPE cells are suitable in vitro RPE models for drug transport studies. Embryonic stem cell model might provide a novel tool to study retinal cell differentiation, mechanisms of RPE-derived diseases, drug testing and targeted drug therapy.

Activation of p44/42 in Human Natural Killer Cells Decreases Cell-surface Protein Expression: Relationship to Tributyltin-induced alterations of protein expression

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Dudimah, Fred D.; Abraha, Abraham; Wang, Xiaofei; Whalen, Margaret M.

2010-01-01

Tributyltin (TBT) activates the mitogen activated protein kinase (MAPK), p44/42 in human natural killer (NK) cells. TBT also reduces NK cytotoxic function and decreases the expression of several NK-cell proteins. To understand the role that p44/42 activation plays in TBT-induced loss of NK cell function, we have investigated how selective activation of p44/42 by phorbol 12-myristate 13-acetate (PMA) affects NK cells. Previously we showed that PMA caused losses of lytic function similar to those seen with TBT exposures. Here we examined activation of p44/42 in the regulation of NK-cell protein expression and how this regulation may explain the protein expression changes seen with TBT exposures. NK cells exposed to PMA were examined for levels of cell-surface proteins, granzyme mRNA, and perforin mRNA expression. The expression of CD11a, CD16, CD18, and CD56 were reduced, perforin mRNA levels were unchanged and granzyme mRNA levels were increased. To verify that activation of p44/42 was responsible for the alterations seen in CD11a, CD16, CD18, and CD56 with PMA, NK cells were treated with the p44/42 pathway inhibitor (PD98059) prior to PMA exposures. In the presence of PD98059, PMA caused no decreases in the expression of the cell-surface proteins. Results of these studies indicate that the activation of p44/42 may lead to the loss of NK cell cytotoxic function by decreasing the expression of CD11a, CD16, CD18, and CD56. Further, activation of p44/42 appears to be at least in part responsible for the TBT-induced decreases in expression of CD16, CD18, and CD56. PMID:20883105

HIV Cell-to-Cell Spread Results in Earlier Onset of Viral Gene Expression by Multiple Infections per Cell.

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Mikaël Boullé

2016-11-01

Full Text Available Cell-to-cell spread of HIV, a directed mode of viral transmission, has been observed to be more rapid than cell-free infection. However, a mechanism for earlier onset of viral gene expression in cell-to-cell spread was previously uncharacterized. Here we used time-lapse microscopy combined with automated image analysis to quantify the timing of the onset of HIV gene expression in a fluorescent reporter cell line, as well as single cell staining for infection over time in primary cells. We compared cell-to-cell spread of HIV to cell-free infection, and limited both types of transmission to a two-hour window to minimize differences due to virus transit time to the cell. The mean time to detectable onset of viral gene expression in cell-to-cell spread was accelerated by 19% in the reporter cell line and by 35% in peripheral blood mononuclear cells relative to cell-free HIV infection. Neither factors secreted by infected cells, nor contact with infected cells in the absence of transmission, detectably changed onset. We recapitulated the earlier onset by infecting with multiple cell-free viruses per cell. Surprisingly, the acceleration in onset of viral gene expression was not explained by cooperativity between infecting virions. Instead, more rapid onset was consistent with a model where the fastest expressing virus out of the infecting virus pool sets the time for infection independently of the other co-infecting viruses.

Polyclonal T-cells express CD1a in Langerhans cell histiocytosis (LCH lesions.

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Jennifer A West

Full Text Available Langerhans cell histiocytosis (LCH is a complex and poorly understood disorder that has characteristics of both inflammatory and neoplastic disease. By using eight-colour flow cytometry, we have identified a previously unreported population of CD1a(+/CD3(+ T-cells in LCH lesions. The expression of CD1a is regarded as a hallmark of this disease; however, it has always been presumed that it was only expressed by pathogenic Langerhans cells (LCs. We have now detected CD1a expression by a range of T-cell subsets within all of the LCH lesions that were examined, establishing that CD1a expression in these lesions is no longer restricted to pathogenic LCs. The presence of CD1a(+ T-cells in all of the LCH lesions that we have studied to date warrants further investigation into their biological function to determine whether these cells are important in the pathogenesis of LCH.

Autoimmune Regulator (AIRE) Is Expressed in Spermatogenic Cells, and It Altered the Expression of Several Nucleic-Acid-Binding and Cytoskeletal Proteins in Germ Cell 1 Spermatogonial (GC1-spg) Cells.

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Radhakrishnan, Karthika; Bhagya, Kongattu P; Kumar, Anil Tr; Devi, Anandavalli N; Sengottaiyan, Jeeva; Kumar, Pradeep G

2016-08-01

Autoimmune regulator (AIRE) is a gene associated with autoimmune polyendocrinopathy-candidiasis-ectodermal dystrophy (APECED). AIRE is expressed heavily in the thymic epithelial cells and is involved in maintaining self-tolerance through regulating the expression of tissue-specific antigens. The testes are the most predominant extrathymic location where a heavy expression of AIRE is reported. Homozygous Aire-deficient male mice were infertile, possibly due to impaired spermatogenesis, deregulated germ cell apoptosis, or autoimmunity. We report that AIRE is expressed in the testes of neonatal, adolescent, and adult mice. AIRE expression was detected in glial cell derived neurotrophic factor receptor alpha (GFRα)(+) (spermatogonia), GFRα(-)/synaptonemal complex protein (SCP3)(+) (meiotic), and GFRα(-)/Phosphoglycerate kinase 2 (PGK2)(+) (postmeiotic) germ cells in mouse testes. GC1-spg, a germ-cell-derived cell line, did not express AIRE. Retinoic acid induced AIRE expression in GC1-spg cells. Ectopic expression of AIRE in GC1-spg cells using label-free LC-MS/MS identified a total of 371 proteins that were differentially expressed. 100 proteins were up-regulated, and 271 proteins were down-regulated. Data are available via ProteomeXchange with identifier PXD002511. Functional analysis of the differentially expressed proteins showed increased levels of various nucleic-acid-binding proteins and transcription factors and a decreased level of various cytoskeletal and structural proteins in the AIRE overexpressing cells as compared with the empty vector-transfected controls. The transcripts of a select set of the up-regulated proteins were also elevated. However, there was no corresponding decrease in the mRNA levels of the down-regulated set of proteins. Molecular function network analysis indicated that AIRE influenced gene expression in GC1-spg cells by acting at multiple levels, including transcription, translation, RNA processing, protein transport, protein

Exosomes from asbestos-exposed cells modulate gene expression in mesothelial cells.

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Munson, Phillip; Lam, Ying-Wai; Dragon, Julie; MacPherson, Maximilian; Shukla, Arti

2018-03-19

Asbestos exposure is a determinate cause of many diseases, such as mesothelioma, fibrosis, and lung cancer, and poses a major human health hazard. At this time, there are no identified biomarkers to demarcate asbestos exposure before the presentation of disease and symptoms, and there is only limited understanding of the underlying biology that governs asbestos-induced disease. In our study, we used exosomes, 30-140 nm extracellular vesicles, to gain insight into these knowledge gaps. As inhaled asbestos is first encountered by lung epithelial cells and macrophages, we hypothesize that asbestos-exposed cells secrete exosomes with signature proteomic cargo that can alter the gene expression of mesothelial cells, contributing to disease outcomes like mesothelioma. In the present study using lung epithelial cells (BEAS2B) and macrophages (THP-1), we first show that asbestos exposure causes changes in abundance of some proteins in the exosomes secreted from these cells. Furthermore, exposure of human mesothelial cells (HPM3) to these exosomes resulted in gene expression changes related to epithelial-to-mesenchymal transition and other cancer-related genes. This is the first report to indicate that asbestos-exposed cells secrete exosomes with differentially abundant proteins and that those exosomes have a gene-altering effect on mesothelial cells.-Munson, P., Lam, Y.-W., Dragon, J. MacPherson, M., Shukla, A. Exosomes from asbestos-exposed cells modulate gene expression in mesothelial cells.

Characterization of TLX expression in neural stem cells and progenitor cells in adult brains.

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Li, Shengxiu; Sun, Guoqiang; Murai, Kiyohito; Ye, Peng; Shi, Yanhong

2012-01-01

TLX has been shown to play an important role in regulating the self-renewal and proliferation of neural stem cells in adult brains. However, the cellular distribution of endogenous TLX protein in adult brains remains to be elucidated. In this study, we used immunostaining with a TLX-specific antibody to show that TLX is expressed in both neural stem cells and transit-amplifying neural progenitor cells in the subventricular zone (SVZ) of adult mouse brains. Then, using a double thymidine analog labeling approach, we showed that almost all of the self-renewing neural stem cells expressed TLX. Interestingly, most of the TLX-positive cells in the SVZ represented the thymidine analog-negative, relatively quiescent neural stem cell population. Using cell type markers and short-term BrdU labeling, we demonstrated that TLX was also expressed in the Mash1+ rapidly dividing type C cells. Furthermore, loss of TLX expression dramatically reduced BrdU label-retaining neural stem cells and the actively dividing neural progenitor cells in the SVZ, but substantially increased GFAP staining and extended GFAP processes. These results suggest that TLX is essential to maintain the self-renewing neural stem cells in the SVZ and that the GFAP+ cells in the SVZ lose neural stem cell property upon loss of TLX expression. Understanding the cellular distribution of TLX and its function in specific cell types may provide insights into the development of therapeutic tools for neurodegenerative diseases by targeting TLX in neural stem/progenitors cells.

Maesopsin 4-O-beta-D-glucoside, a natural compound isolated from the leaves of Artocarpus tonkinensis, inhibits proliferation and up-regulates HMOX1, SRXN1 and BCAS3 in acute myeloid leukemia.

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Pozzesi, N; Pierangeli, S; Vacca, C; Falchi, L; Pettorossi, V; Martelli, M P; Thuy, T T; Ninh, P T; Liberati, A M; Riccardi, C; Sung, T V; Delfino, D V

2011-06-01

The leaves of Artocarpus tonkinensis are used in Vietnamese traditional medicine for treatment of arthritis, and the compound maesopsin 4-O-β-D-glucoside (TAT-2), isolated from them, inhibits the proliferation of activated T cells. Our goal was to test the anti-proliferative activity of TAT-2 on the T-cell leukemia, Jurkat, and on the acute myeloid leukemia, OCI-AML. TAT-2 inhibited the growth of OCI-AML (and additional acute myeloid leukemia cells) but not Jurkat cells. Growth inhibition was shown to be due to inhibition of proliferation rather than increase in cell death. Analysis of cytokine release showed that TAT-2 stimulated the release of TGF-β, yet TGF-β neutralization did not reverse the maesopsin-dependent effect. Gene expression profiling determined that maesopsin modulated 19 identifiable genes. Transcription factor CP2 was the gene most significantly modulated. Real-time PCR validated that up-regulation of sulphiredoxin 1 homolog (SRXN1), hemeoxygenase 1 (HMOX1), and breast carcinoma amplified sequence 3 (BCAS3) were consistently modulated.

A Metabolic Biofuel Cell: Conversion of Human Leukocyte Metabolic Activity to Electrical Currents

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Cui X Tracy

2011-05-01

Full Text Available Abstract An investigation of the electrochemical activity of human white blood cells (WBC for biofuel cell (BFC applications is described. WBCs isolated from whole human blood were suspended in PBS and introduced into the anode compartment of a proton exchange membrane (PEM fuel cell. The cathode compartment contained a 50 mM potassium ferricyanide solution. Average current densities between 0.9 and 1.6 μA cm-2 and open circuit potentials (Voc between 83 and 102 mV were obtained, which were both higher than control values. Cyclic voltammetry was used to investigate the electrochemical activity of the activated WBCs in an attempt to elucidate the mechanism of electron transfer between the cells and electrode. Voltammograms were obtained for the WBCs, including peripheral blood mononuclear cells (PBMCs - a lymphocyte-monocyte mixture isolated on a Ficoll gradient, a B lymphoblastoid cell line (BLCL, and two leukemia cell lines, namely K562 and Jurkat. An oxidation peak at about 363 mV vs. SCE for the PMA (phorbol ester activated primary cells, with a notable absence of a reduction peak was observed. Oxidation peaks were not observed for the BLCL, K562 or Jurkat cell lines. HPLC confirmed the release of serotonin (5-HT from the PMA activated primary cells. It is believed that serotonin, among other biochemical species released by the activated cells, contributes to the observed BFC currents.

Gene expression of manganese superoxide dismutase in human glioma cells

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Novi S. Hardiany

2010-02-01

Full Text Available Aim This study analyze the MnSOD gene expression as endogenous antioxidant in human glioma cells compared with leucocyte cells as control.Methods MnSOD gene expression of 20 glioma patients was analyzed by measuring the relative expression of mRNA and enzyme activity of MnSOD in brain and leucocyte cells. The relative expression of mRNA MnSOD was determined by using quantitative Real Time RT-PCR and the enzyme activity of MnSOD using biochemical kit assay (xantine oxidase inhibition. Statistic analysis for mRNA and enzyme activity of MnSOD was performed using Kruskal Wallis test.Results mRNA of MnSOD in glioma cells of 70% sample was 0.015–0.627 lower, 10% was 1.002-1.059 and 20% was 1.409-6.915 higher than in leucocyte cells. Also the specific activity of MnSOD enzyme in glioma cells of 80% sample showed 0,064-0,506 lower and 20% sample was 1.249-2.718 higher than in leucocyte cells.Conclusion MnSOD gene expression in human glioma cells are significantly lower than its expression in leucocytes cells. (Med J Indones 2010; 19:21-5Keywords : MnSOD, glioma, gene expression

Expression of cadherin and NCAM in human small cell lung cancer cell lines and xenografts

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Rygaard, K; Møller, C; Bock, E

1992-01-01

characterised, the cadherin family and the Ig superfamily member, neural cell adhesion molecule (NCAM). We investigated expression of these two adhesion molecule families in small cell lung cancer (SCLC) cell lines and xenografts by immunoblotting. Nineteen tumours established from 15 patients with SCLC were......Tumour cell adhesion, detachment and aggregation seem to play an important part in tumour invasion and metastasis, and numerous cell adhesion molecules are expressed by tumour cells. Several families of cell-cell adhesion molecules have been described, of which two groups are particularly well...... embryonic development, which may play a role in connection with tumour invasion and metastasis, was found in 14/18 NCAM expressing SCLC tumours. Individual tumours grown as cell lines and as nude mouse xenografts showed no qualitative differences in cadherin or NCAM expression....