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Effect of IFNα-2a on Fas expression and apoptosis rate of peripheral blood cytotoxic T cells in patients with hepatitis B 被引量:4
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作者 Institute of Infectious Diseases, Zhejiang University School of Medicine, Hangzhou 310003, China (Hou W, Liu KZ, Li MW and Wo JE) 《Hepatobiliary & Pancreatic Diseases International》 SCIE CAS 2005年第3期403-405,共3页
Interferon(IFN) with antiviral and im-munomodulatory activities is one of the most important therapeutic agents for the treatment of chronic hepatitis. The apoptotic effect of IFN is influenced by cell type and the ty... Interferon(IFN) with antiviral and im-munomodulatory activities is one of the most important therapeutic agents for the treatment of chronic hepatitis. The apoptotic effect of IFN is influenced by cell type and the types of IFN, which suppresses proliferation and induces apoptosis in some cell types while inhibiting apoptosis in others. The aim of this study was to explore the effect of IFNα-2a on Fas expression and the apoptosis rate of peripheral blood cytotoxic T cells (CTLs) in patients with hepatitis B. METHODS:Peripheral blood mononuclear cells were isolated from 26 patients with hepatitis B including 16 patients with chronic hepatitis B and 10 patients with chronic severe hepatitis B. Fas expression and apoptosis rate of CTLs were analyzed with flow cytometry before and after IFNα-2a treatment. RESULTS:Before IFNα-2a treatment, Fas expression and apoptosis rate of CTLs from patients with chronic hepatitis B were significantly higher than those from patients with chronic severe hepatitis B and healthy controls respectively. No significant difference was observed between Fas expression and apoptosis rate of CTLs from patients with chronic severe hepatitis B and healthy controls. After IFNα-2a treatment,Fas expression and apoptosis rate of CTLs from different groups were compared with those before IFNα-2a treatment, showing no significant difference despite alternation of different degree. CONCLUSIONS:Activation induced cell death (AICD) exists in peripheral blood CTLs from patients with hepatitis B. No effect of IFNα-2a exerts on Fas expression and apoptosis rate of Fas in patients with hepatitis B. 展开更多
关键词 IFNα-2a hepatitis B cytotoxic t cells FAS activation induced cell death
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In-vitro activation of cytotoxic T lymphocytes by fusion of mouse hepatocellular carcinoma cells and lymphotactin gene-modified dendritic cells 被引量:11
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作者 Xi-Ling Sheng Hao Zhang 《World Journal of Gastroenterology》 SCIE CAS CSCD 2007年第44期5944-5950,共7页
AIM: To investigate the in-vitro activation of cytotoxic T lymphocytes (CTLs) by fusion of mouse hepatocellular carcinoma (HCC) ceils and lymphotactin gene-modified dendritic cells (DCs). METHODS: Lymphotactin... AIM: To investigate the in-vitro activation of cytotoxic T lymphocytes (CTLs) by fusion of mouse hepatocellular carcinoma (HCC) ceils and lymphotactin gene-modified dendritic cells (DCs). METHODS: Lymphotactin gene modified DCs (DCLptn) were prepared by lymphotactin recombinant adenovirus transduction of mature DCs which differentiated from mouse bone marrow cells by stimulation with granulocyte/macrophage colony-stimulating factor (GM- CSF), interleukin-4 (IL-4) and tumor necrosis factor alpha (TNF-α). DCLptn and H22 fusion was prepared using 50% PEG. Lymphotactin gene and protein expression levels were measured by RT-PCR and ELISA, respectively. Lymphotactin chemotactic responses were examined by in-vitro chemotaxis assay. In-vitro activation of CTl_s by DCLptn/H22 fusion was measured by detecting CD25 expression and cytokine production after autologous T cell stimulation. Cytotoxic function of activated T lymphocytes stimulated with DCLptn/H22 cells was determined by LDH cytotoxicity assay. RESULTS: Lymphotactin gene could be efficiently transduced to DCs by adenovirus vector and showed an effective biological activity. After fusion, the hybrid DCLptn/H22 cells acquired the phenotypes of both DCLptn and H22 cells. In T cell proliferation assay, flow cytometry showed a very high CD25 expression, and cytokine release assay showed a significantly higher concentration of IFN-α, and IL-2 in DCLptn/H22 group than in DCLptn, DCLptn+H22, DC/H22 or H22 groups. Cytotoxicity assay revealed that T cells derived from DCLptn/H22 group had much higher anti-tumor activity than those derived from DCLptn, H22, DCLptn + H22, DC/H22 groups. CONCLUSION: Lymphotactin gene-modified dendritoma induces T-cell proliferation and strong CTL reaction against allogenic HCC cells. Immunization-engineered fusion hybrid vaccine is an attractive strategy in prevention and treatment of HCC metastases. 展开更多
关键词 Hepatocellular carcinoma Dendritic cell cytotoxic t lymphocyte
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Dendritic cells engineered to secrete anti-Dc R3 antibody augment cytotoxic T lymphocyte response against pancreatic cancer in vitro 被引量:12
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作者 Jiang Chen Xiao-Zhong Guo +2 位作者 Hong-Yu Li Jia-Jun Zhao Wen-Da Xu 《World Journal of Gastroenterology》 SCIE CAS 2017年第5期817-829,共13页
AIM To investigate the enhanced cytotoxic T lymphocyte responses against pancreatic cancer (PC) in vitro induced by dendritic cells (DCs) engineered to secrete anti-DcR3 monoclonal antibody (mAb). METHODS DCs, T lymph... AIM To investigate the enhanced cytotoxic T lymphocyte responses against pancreatic cancer (PC) in vitro induced by dendritic cells (DCs) engineered to secrete anti-DcR3 monoclonal antibody (mAb). METHODS DCs, T lymphocytes and primary PC cells were obtained from PC patients. DCs were transfected with a designed humanized anti-DcR3 monoclonal antibody heavy and light chain mRNA and/or total tumor RNA (DC-tumor-anti-DcR3 RNA or DC-total tumor RNA) by using electroporation technology. The identification, concentration and function of anti-DcR3 mAb secreted by DC-tumor-anti-DcR3 RNA were determined by western blotting and enzyme-linked immunosorbent assay. After co-culturing of autologous isolated PC cells with target DCs, the effects of secreting anti-DcR3 mAb on RNA-DCs' viability and apoptosis were assessed by MTT assay and flow cytometry. Analysis of enhanced antigen-specific immune response against PC induced by anti-DcR3 mAb secreting DCs was performed using a Cr-51 releasing test. T cell responses induced by RNAloaded DCs were analyzed by measuring cytokine levels, including IFN-gamma, IL-10, IL4, TNF-alpha and IL-12. RESULTS The anti-DcR3 mAb secreted by DCs reacted with recombinant human DcR3 protein and generated a band with 35 kDa molecular weight. The secreting mAb was transient, peaking at 24 h and becoming undetectable after 72 h. After co-incubation with DCtumor- anti-DcR3 RNA for designated times, the DcR3 level in the supernatant of autologous PC cells was significantly down-regulated (P < 0.05). DCs secreting anti-DcR3 mAb could improve cell viability and slow down the apoptosis of RNA-loaded DCs, compared with DC-total tumor RNA (P < 0.01). The anti-DcR3 mAb secreted by DC-tumor-anti-DcR3 RNA could enhance the induction of cytotoxic T lymphocytes (CTLs) activity toward RNA-transfected DCs, primary tumor cells, and PC cell lines, compared with CTLs stimulated by DC-total tumor RNA or control group (P < 0.05). Meanwhile, the antigen-specific CTL responses were MHC class I-restricted. The CD4+ T cells and CD8+ T cells incubated with anti-DcR3 mAb secreting DCs could produce extremely higher level IFN-gamma and lower level IL4 than those incubated with DC-total tumor RNA or controls (P < 0.01). CONCLUSION DCs engineered to secrete anti-DcR3 antibody can augment CTL responses against PC in vitro, and the immune-enhancing effects may be partly due to their capability of down-regulating DC apoptosis and adjusting the Th1/Th2 cytokine network. 展开更多
关键词 Dendritic cell Antibody-encoding RNA DCR3 cytotoxic t lymphocyte response Pancreatic Cancer
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Frequencies and Characterization of HBV-specific Cytotoxic T Lymphocytes in Self-limited and Chronic Hepatitis B Viral Infection in China 被引量:2
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作者 杨新星 郝友华 +5 位作者 刘贽 陈玲 丁红晖 赵西平 陆蒙吉 杨东亮 《Journal of Huazhong University of Science and Technology(Medical Sciences)》 SCIE CAS 2009年第5期567-574,共8页
Hepatitis B virus (HBV)-specific cytotoxic T lymphocytes (CTLs) are believed to play a major role in viral clearance and disease pathogenesis during HBV infection. To clarify the differences in host immune respons... Hepatitis B virus (HBV)-specific cytotoxic T lymphocytes (CTLs) are believed to play a major role in viral clearance and disease pathogenesis during HBV infection. To clarify the differences in host immune responses between self-limited and chronic HBV infections, we constructed three HLA-A*0201/HBV tetramers with immunodominant epitopes of core18-27, polymerase 575-583 and envelope 335-343, and analyzed the HBV-specific CTLs in peripheral blood mononuclear cells (PBMCs) from patients infected with HBV. The frequencies and expansion ability of HBV-specific CD8+T cells in most self-limited HBV infected individuals were higher than those in chronic HBV-infected patients. HBV-specific CD8+T cells could be induced by in vitro peptide stimulation from chronic patients with a low level of serum HBV-DNA but not from those with a high level of serum HBV-DNA. In chronic infection, no significant correlation was found either between the frequencies of HBV-specific CD8^+ T cells and the viral load, or between the frequencies and the levels of alanine transaminase. Our results suggested that the frequencies of HBV-specific CTLs are not the main determinant of immune-mediated protection in chronic HBV infection and immunotherapeutic approaches should be aimed at not only boosting a HBV-specific CD8^+T response but also improving its function. 展开更多
关键词 hepatitis B virus cytotoxic t lymphocyte HLA-A*0201
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Natural epitope variants of the hepatitis C virus impair cytotoxic T lymphocyte activity 被引量:1
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作者 Shuping Wang Rico Buchli +4 位作者 Jennifer Schiller Jianen Gao Rodney S VanGundy William H Hildebrand David D Eckels 《World Journal of Gastroenterology》 SCIE CAS CSCD 2010年第16期1953-1969,共17页
AIM:To understand how interactions between hepatitis C virus(HCV) and the host's immune system might lead to viral persistence or effective elimination of HCV.METHODS:Nucleotides 3519-3935 of the non-structural 3(... AIM:To understand how interactions between hepatitis C virus(HCV) and the host's immune system might lead to viral persistence or effective elimination of HCV.METHODS:Nucleotides 3519-3935 of the non-structural 3(NS3) region were amplified by using reverse transcription polymerase chain reaction(PCR).PCR products of the HCV NS3 regions were integrated into a PCR T7TOPO TA vector and then sequenced in both directions using an automated DNA sequencer.Relative major histocompatibility complex binding levels of wild-type and variant peptides were performed by fluorescence polarization-based peptide competition assays.Peptides with wild type and variant sequences of NS3 were synthesized locally using F-moc chemistry and purified by high-performance liquid chromatography.Specific cytotoxic T lymphocytes(CTLs) clones toward HCV NS3 wild-type peptides were generated through limiting dilution cloning.The CTL clones specifically recognizing HCV NS3 wild-type peptides were tested by tetramer staining and flow cytometry.Cytolytic activity of CTL clones was measured using target cells labeled with the fluorescence enhancing ligand,DELFIA EuTDA.RESULTS:The pattern of natural variants within three human leukocyte antigen(HLA)-A2-restricted NS3 epitopes has been examined in one patient with chronic HCV infection at 12,28 and 63 mo post-infection.Results obtained may provide convincing evidence of immune selection pressure for all epitopes investigated.Statistical analysis of the extensive sequence variation found within these NS3 epitopes favors a Darwinian selection model of variant viruses.Mutations within the epitopes coincided with the decline of CTL responses,and peptide-binding studies suggested a signif icant impact of the mutation on T cell recognition rather than peptide presentation by HLA molecules.While most variants were either not recognized or elicited low responses,such could antagonize CTL responses to target cells pulsed with wild-type peptides.CONCLUSION:Cross-recognition of CTL epitopes from wild-type and naturally-occurring HCV variants may lead to impaired immune responses and ultimately contribute to viral persistence. 展开更多
关键词 EPItOPES Human t Cells cytotoxic ANERGY VIRAL
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Identification of the epitopes on HCV core protein recognized by HLA-A2 restricted cytotoxic T lymphocytes 被引量:11
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作者 Hong-Chao Zhou De-Zhong Xu Xue-Ping Wang Jing-Xia Zhang Ying-Huang Yong-Ping Yan Yong Zhu Bo-Quan Jin Department of Epidemiology,the Fourth Military Medical University,Xi’an 710033,Shaanxi Province,ChinaDepartment of Immunology,the Fourth Military Medical University,Xi’an 710033,Shaanxi Province,China 《World Journal of Gastroenterology》 SCIE CAS CSCD 2001年第4期583-586,共4页
AIM: To identify hepatitis C virus(HCV) core protein epitopes recognized by HLA-A2 restricted cytotoxic T lymphocyte (CTL). METHODS: Utilizing the method of computer prediction followed by a 4h(51)Cr release assay con... AIM: To identify hepatitis C virus(HCV) core protein epitopes recognized by HLA-A2 restricted cytotoxic T lymphocyte (CTL). METHODS: Utilizing the method of computer prediction followed by a 4h(51)Cr release assay confirmation. RESULTS: The results showed that peripheral blood mononuclear cells (PBMC) obtained from two HLA-A2 positive donors who were infected with HCV could lyse autologous target cells labeled with peptide &quot;ALAHGVRAL (core 150-158)&quot;. The rates of specific lysis of the cells from the two donors were 37.5% and 15.8%, respectively. Blocking of the CTL response with anti-CD4 mAb caused no significant decrease of the specific lysis. But blocking of CTL response with anti-CD8 mAb could abolish the lysis. CONCLUSION: The peptide (core 150-158) is the candidate epitope recognized by HLAA2 restricted CTL. 展开更多
关键词 Amino Acid Sequence Antibodies Viral B-LYMPHOCYtES Cell Line Epitope Mapping HLA-A2 Antigen HEPACIVIRUS Hepatitis C Humans Peptide Fragments Predictive Value of tests Research Support Non-U.S. Gov't t-Lymphocytes cytotoxic Viral Core Proteins
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Association of Graves’ disease and Graves’ ophthalmopathy with the polymorphisms in promoter and exon 1 of cytotoxic T lymphocyte associated antigen-4 gene 被引量:11
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作者 ZHANG Qin YANG Yun-mei LV Xue-ying 《Journal of Zhejiang University-Science B(Biomedicine & Biotechnology)》 SCIE CAS CSCD 2006年第11期887-891,共5页
Objective: To investigate the association of Graves’ disease and Graves’ ophthalmopathy with the C/T transition polymorphism at position –318 of promoter and the A/G transition polymorphism at position 49 of exon 1... Objective: To investigate the association of Graves’ disease and Graves’ ophthalmopathy with the C/T transition polymorphism at position –318 of promoter and the A/G transition polymorphism at position 49 of exon 1 within cytotoxic T lymphocyte associated antigen-4 (CTLA-4) gene. Methods: Thirty-three patients with ophthalmopathy of Graves’ disease, fifty-six Graves’ patients without ophthalmopathy and sixty normal subjects as control were involved in the present case-control study. The polymorphisms were evaluated by polymerase chain reaction fragment length polymorphism (PCR-RFLP). Com-parisons were made of gene frequencies and allele frequencies between the groups. Results: The gene frequencies of CT and allele frequencies of T were much higher in Graves’ patients with ophthalmopathy than that in the group without ophthalmopathy (P=0.020, P=0.019). The gene frequencies of GG and allele frequencies of G in patients with Graves’ disease were significantly increased as compared with control group (P=0.008, P=0.007). The data suggest that smokers with Graves’ disease seemed to be more predisposed to ophthalmopathy than non-smokers (P=0.018). Conclusion: Our results suggest that an allele of T at position –318 of promoter is associated with genetic susceptibility to Graves’ ophthalmopathy while an allele of G at position 49 of exon 1 is associated with genetic susceptibility to Graves’ disease instead. Smoking is believed to be a major risk factor for ophthalmo-pathy. 展开更多
关键词 Graves' ophthalmopathy cytotoxic t lymphocyte associated antigen-4 (CtLA-4) gene Gene frequency Susceptibility gene
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Cytotoxicity study of ethanol extract of the stem bark of asam kandis (Garcinia cowa Roxb.) on T47D breast cancer cell line 被引量:1
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作者 Elidahanum Husni Faras Nahari +2 位作者 Yan Wirasti Fatma Sri Wahyuni Dachriyanus 《Asian Pacific Journal of Tropical Biomedicine》 SCIE CAS 2015年第3期249-252,共4页
Objective:To investigate the cytotoxic effect of ethanol extract of the stem bark of asam kandis[Garcinia cowa Roxb.(G.cowa)]on T47 D breast cancer cell line.Methods:The cytotoxicity of ethanol extract was carried out... Objective:To investigate the cytotoxic effect of ethanol extract of the stem bark of asam kandis[Garcinia cowa Roxb.(G.cowa)]on T47 D breast cancer cell line.Methods:The cytotoxicity of ethanol extract was carried out against human breast cancer cell line(T47D) by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide colorimetric assay.The extract was added at various concentrations(0.1.1,10 and 100 μg/mL).The level of cytotoxicity was determined by calculating the level of IC_(50),that was based on the percentage of the cell death after 24 h treatment with the extract.Cell morphological changes were observed by using inverted microscope.Results:The 3-(4.5-dimelhylthiazol-2-yl)-2.5-diphenyltelrazolium bromide assay showed that ethanol extract of G.cowa exhibited significant cytotoxic effect on T47 D with IC_(50) value of(5.10+1.68) μg/mL.Morphological alteration of the cell lines after exposure to ethanol extract of G.cowa was observed under phase contrast microscope in a dosc-dependent manner.ConclusionsThe results suggest the possible use of ethanol extract of asam kandis for preparing herbal medicine for cancer-related ailments. 展开更多
关键词 GARCINIA cowa Roxb cytotoxicItY t47D BREASt CANCER cell LINE
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Cytotoxicity of seven recent dentine bonding agents on mouse 3T3 fibroblast cells 被引量:2
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作者 Annette Olivier Sias R. Grobler Yusuf Osman 《Open Journal of Stomatology》 2012年第4期244-250,共7页
Today it is generally accepted that most bonding agents are cytotoxic. In this study the relative cytotoxicity of seven recent dentine bonding agents on mouse 3T3 fibroblast cells were investigated. Materials and Meth... Today it is generally accepted that most bonding agents are cytotoxic. In this study the relative cytotoxicity of seven recent dentine bonding agents on mouse 3T3 fibroblast cells were investigated. Materials and Methods. Near-confluent mouse 3T3 fibroblast cells were exposed to Dulbecco Modified Eagle’s Medium containing extractions from the seven different bonding agents. The cell survival rate was then determined using the standard MTT assay. Results. The cell survival rate ranking is: iBond (94%) < Gbond (78%) < Xeno V (71%) < Adper Easy Bond (63%) < Xeno V+ (61%) < Adper Scotchbond SE (33%) < XP Bond (32%). Part A of Adper Scotchbond SE had a survival rate of 35% and part B 38%. These two parts did not differ significantly. Adper Scotchbond SE and XP Bond do not differ significantly. While Xeno V+, Xeno V and Adper Easy Bond do not differ. (p < 5%;Tukey-Kramer Multiple-Comparison Test). Conclusion. All of the tested adhesive bonding agents were cytotoxic with survival rate of 3T3 cells between 94% to 31%. Of the 7 bonding agents tested iBond was found to be only slightly toxic and by far the least toxic. The two bonding agents (XP Bond and Adper Scotchbond SE) containing UDMA plus TEGDMA plus HEMA plus camphorquinone were found to be the most toxic. 展开更多
关键词 cytotoxicItY BONDING AGENtS MOUSE 3t3 FIBROBLASt
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Effect of cytotoxic T-lymphocyte antigen-4,TNF-alpha polymorphisms on osteosarcoma: evidences from a meta-analysis 被引量:3
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作者 Jianwei Liu Junli Wang +1 位作者 Weiping Jiang Yujin Tang 《Chinese Journal of Cancer Research》 SCIE CAS CSCD 2013年第6期671-678,共8页
Objective: Previous studies have investigated the role of cytotoxic T-lymphocyte antigen-4 (CTLA-4) and tumor necrosis factor-alpha (TNF-a) in carcinogenesis of osteosarcoma, but their results were inconsistent. ... Objective: Previous studies have investigated the role of cytotoxic T-lymphocyte antigen-4 (CTLA-4) and tumor necrosis factor-alpha (TNF-a) in carcinogenesis of osteosarcoma, but their results were inconsistent. We aimed to clarify the associations between CTLA-4, TNF-a polymorphism and osteosarcoma risk by using meta-analysis. Methods: We searched relevant studies without language restriction in PubMed, EMbase, Cochrane Library, Google Scholar databases, Chinese National Knowledge Infrastructure (CNKI) and conference literature in humans published prior to March 2013. The strengths of the associations between genetic variants and osteosarcoma risk were estimated by odds ratio (OR) with 95% confidence interval (95% CI). Results: A total of seven studies with 1,198 osteosarcoma patients and 1,493 controls were selected. Four studies were eligible for CTLA-4 (1,003 osteosarcoma and 1,162 controls), and three studies for TNF-a (195 osteosarcoma and 331 controls). Pooled results showed that rs231775 polymorphism of CTLA-4 was associated with osteosarcoma risk (GG vs. AA: OR=1.63, 95% CI=1.24-2.13; GG + GA vs. AA: OR=1.56, 95% CI=1.21-2.01; AA + GA vs. GG: OR=0.83, 95% CI=0.71-0.97; G vs. A: OR=1.21, 95% CI=1.08-1.36). No significant heterogeneity was observed across the studies. No significant associations were found between rs5742909 polymorphism of CTLA-4 or rs1800629 polymorphism of TNF-a and osteosarcoma risk. Conclusions: These results suggest that the rs231775 polymorphism of CTLA-4 may play an important role in carcinogenesis of osteosarcoma. 展开更多
关键词 cytotoxic t-lymphocyte antigen-4 (CtLA-4) tumor necrosis factor-alpha tNF-a) OStEOSARCOMA genetic polymorphism
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Glypican-3-specific cytotoxic T lymphocytes induced by human leucocyte antigen-A*0201-restricted peptide effectively kill hepatocellular carcinoma cells in vitro
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作者 Jiang-Zheng Zeng Yu Liu +5 位作者 Fen Huang Zhi-Hui He Huamao Sun Yan-Da Lu Jun-Hua Lei Rong-Cheng Luo 《Asian Pacific Journal of Tropical Medicine》 SCIE CAS 2017年第11期1084-1089,共6页
Objective: To investigate potential human leucocyte antigen(HLA)-A2-restricted epitope peptides of glypican-3(GPC3) and determine the cytotoxicity of peptidespecific cytotoxic T lymphocytes(CTLs) against hepatocellula... Objective: To investigate potential human leucocyte antigen(HLA)-A2-restricted epitope peptides of glypican-3(GPC3) and determine the cytotoxicity of peptidespecific cytotoxic T lymphocytes(CTLs) against hepatocellular carcinoma(HCC) cells.Methods: The potential HLA-A*0201-restricted GPC3 peptides were screened using computer algorithms, T2 cell-binding affinity and stability of peptide/HLA-A*0201 complex assay. The peptide-specific CTLs were generated and their cytotoxicity against GPC3+SMMC 7721 and Hep G2 cells was detected using IFN-g based enzymelinked immunospot and lactate dehydrogenase release assays in vitro.Results: A total of six peptides were identified for bindings to HAL-A2 and the GPC3522–530 and GPC3 229–237 peptides with HLA-A*0201 molecules displayed high binding affinity and stability. The CTLs induced by the GPC3 522–530 or positive control GPC3 144–152 peptide responded to the peptide by producing IFN-g, which were abrogated by treatment with anti-HLA-A2 antibody. The GPC3 522–530-specific CTLs responded to and killed SMMC 7721 and Hep G2 cells, instead of GPC3-silenced SMMC7721 or Hep G2 cells. GPC3 522–530-specific CTLs response to HCC cells was blocked by anti-HLA-A2 antibody.Conclusions: The GPC3 522–530 peptide contains antigen-determinant and its specific CTLs can effectively kill HCC in a HLA-A2-restricted and peptide-dependent manner. Our findings suggest that this peptide may be valuable for development of therapeutic vaccine. 展开更多
关键词 GLYPICAN-3 PEPtIDE cytotoxic t lymphocyte Hepatocellular carcinoma
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INVESTIGATION OF INDUCING EFFECT OF SPECIFIC CYTOTOXICITY OF CTLS BY ANTIGEN PEPTIDES FROM T LYMPHOCYTIC LEUKEMIA CELLS
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作者 张桂梅 黄波 +2 位作者 李东 王洪涛 冯作化 《Chinese Journal of Cancer Research》 SCIE CAS CSCD 2003年第4期247-251,共5页
Objective: To investigate the characteristics of specific antitumor immunity induced by antigen peptides mixture from T lymphocytic leukemia cells. Method: Antigen peptides mixtures were prepared from different leuke... Objective: To investigate the characteristics of specific antitumor immunity induced by antigen peptides mixture from T lymphocytic leukemia cells. Method: Antigen peptides mixtures were prepared from different leukemia cell lines and then bound with Hsp70 in vitro. Human peripheral blood mononuclear cells (PBMC) were cultured in vitro, and activated with Hsp70-antigen peptides. The activated PBMC was cultured continuously in vitro, and used as effector cells in vitro test of cytotoxicity to different target cells. Results: The antigen peptides from different leukemia cell lines were peptides mixture and could activate PBMC effectively if they were presented by Hsp70. The activated PBMC could proliferate in the presence of IL-2 and Hsp70-antigen peptides. The proliferative PBMC had specific cytotoxicity to leukemia cells corresponding to the antigen peptides. PBMC activated by antigen peptides from T lymphocytic leukemia cell lines could effectively kill T lymphocytic leukemia cells, and the cytotoxicity of these PBMC to T lymphocytic leukemia cells was significantly stronger than that of PBMC activated by antigen peptides from other leukemia cells (P < 0.05). PBMC activated by either Hut78-peptides or Molt 4-peptides could effectively kill Jurkat cells. And the cytotoxicity of PBMC activated by Hut78/Molt-4-peptides to Jurkat cells was significantly stronger than that of PBMC activated by either Hut78-peptides or Molt-4-peptides alone (P<0.05). Conclusion: Antigen peptides mixture from T lymphocytic leukemia cell lines can induce specific cytotoxic effect to T lymphocytic leukemia cells. There exists cross-reactivity among antigen peptides mixture from different T lymphocytic leukemia cell lines. The cross-reactivity could be amplified by blending of different antigen peptides from different T lymphocytic leukemia cell lines, suggesting that it is possible to prepare broad-spectrum antigen peptide vaccine against T lymphocytic leukemia by using multiple leukemia cell lines. 展开更多
关键词 t lymphocytic leukemia Antigen peptides mixture Specific cytotoxicity
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Perforin Expression in <i>Theileria parva</i>Specific Cytotoxic T Cells Correlates with Cytotoxicity
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作者 Jerome Wendoh Rebecca Waihenya +3 位作者 Rosemary Saya Elias Awino Vishvannath Nene Lucilla Steinaa 《Open Journal of Immunology》 2014年第3期117-127,共11页
Theileria parva is a protozoan parasite that causes the disease East Coast fever in cattle which results in major economic losses in Eastern, Central and Southern Africa. Efforts to generate vaccines involve measureme... Theileria parva is a protozoan parasite that causes the disease East Coast fever in cattle which results in major economic losses in Eastern, Central and Southern Africa. Efforts to generate vaccines involve measurements of cytotoxic activity since CD8 cells are believed to be responsible for protection of the animals. CTL assays are time consuming, and may require use of radioactive material and they also impose a considerable amount of in vitro work, which may skew the response compared to ex vivo assays. Hence it would be beneficial to identify other markers that correlate with the cytotoxicity. In this in vitro study we examined if the number of tetramer positive CD8 cells and the staining intensity of these correlated with lysis of the target cells. Furthermore, we investigated if the expression of the activation marker perforin correlated with the cytotoxicity. Perforin is involved in permeabilization of the cell membrane of the target cell. Bulk CTL lines and purified CD8 cell lines generated from cattle of the A18 BoLA (MHC) type were analysed for the Theileria parva specific immune responses using a peptide-MHC tetramer and antibodies for perforinin FACS analysis. Thelysis of target cells was determined by a chromium release assay. Results demonstrate that the percentage of tetramer positive cells, in six cell lines generated against the whole parasite, correlate with killing of PBMC pulsed with the peptide. The product of the percentages of perforin and tetramer double positive cells and the net MFI of perforin showed a perfect correlation with the cytotoxicity of the peptide pulsed PBMC. Likewise, the product of percentage perforin positive cells and the staining intensity had the best significant correlation with killing of the pulsed PBMC. The present results suggest that perforin could be a possible biomarker for the cytotoxicity to Theileria parva infections/immunizations. 展开更多
关键词 cytotoxic t Cells Biomarkers PERFORIN tHEILERIA parva
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Research progress of follicular cytotoxic T cells in human immunodeficiency virus infection
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作者 Ming Guo 《国际感染病学(电子版)》 CAS 2017年第3期81-85,共5页
Recently, a new type of CD8^+ T cell subset, namely, the CXCR5^+ CD8^+ T cell subset(also called the follicular cytotoxic T cell(TFC) subgroup), has been discovered around B cell follicles. The discovery has aroused w... Recently, a new type of CD8^+ T cell subset, namely, the CXCR5^+ CD8^+ T cell subset(also called the follicular cytotoxic T cell(TFC) subgroup), has been discovered around B cell follicles. The discovery has aroused widespread interest.However, the processes and mechanisms of TFCs taking part in the immune response of the germinal center and their specific roles must still be clearly identified. This paper reviews domestic and foreign studies on factors regulating the phenotype,physiological functions, maturity, and differentiation of TFCs and roles and clinical significance these cells in human immunodeficiency virus infection. Our review has shown good application prospects for TFCs. We believe that further studies on TFCs can provide another tool for cytotherapy of controlling or curing chronic viral infections or tumors. 展开更多
关键词 FOLLICULAR cytotoxic t CELLS HIV INFECtION PROGRESS
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Insights into chitosan hydrogels on dentine bond strength and cytotoxicity
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作者 V. Tamara Perchyonok Sias Grobler +2 位作者 Shengmiao Zhang Annette Olivier Theunis Oberholzer 《Open Journal of Stomatology》 2013年第1期75-82,共8页
Contemporary dental adhesives show favorable immediate results in terms of bonding effectiveness. However, the durability of resin-dentin bonds is their major problem. Materials and Methods: Preparation of 3 chitosan-... Contemporary dental adhesives show favorable immediate results in terms of bonding effectiveness. However, the durability of resin-dentin bonds is their major problem. Materials and Methods: Preparation of 3 chitosan-antioxidant hydrogels was achieved using modified hydrogel preparation method. Their effect on the bond strength to dentine both short term (after 24 hours) and long term (after 6 months) were evaluated using shear bond strength measurements using Instron Universal Testing Mascine). The SEM was used to study the surface of the hydrogels. The cell survival rate (cytotoxicity) of the antioxidants resveratrol, β-carotene and propolis towards Balb/c 3T3 mouse fibroblast cells was also assessed using the standard MTT assay. Results: It was found that chitosan-H treated dentine gives significantly (p β-carotene (92%) > propolis (68%) > resveratrol (33%). Conclusion: the antioxidant-chitosan hydrogels significantly improved bonding to dentine with or without phosphoric acid treatment. The pH of the growth medium had a high influence on the cell survival rate of Balb/c mouse 3T3 fibroblast cells. The release of the antioxidant β-carotene would not have an influence on the pulp cells. These materials might address the current perspectives for improving bond durability. 展开更多
关键词 Antioxidant-Chitosan HYDROGELS SEM BOND Strength cytotoxicItY Mouse 3t3 FIBROBLASt FIBROBLASt
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Effects of the Cytotoxic T-Cells on the Dynamics of Co-Infection of HIV-1 and Mycobacterium tuberculosis
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作者 Chipo Mufudza Senelani D. Hove-Musekwa Edward T. Chiyaka 《Journal of Tuberculosis Research》 2016年第4期191-212,共23页
Enhancement of the Human Immunodeficiency Virus (HIV) specific cytotoxic T-cells mechanisms in an HIV-1 and Mycobacterium tuberculosis (Mtb) co-infected individual seems to improve the clinical picture of an individua... Enhancement of the Human Immunodeficiency Virus (HIV) specific cytotoxic T-cells mechanisms in an HIV-1 and Mycobacterium tuberculosis (Mtb) co-infected individual seems to improve the clinical picture of an individual by reducing Acquired Immuno Deficiency Syndrome (AIDS) state progression rate. In this paper, we develop a system of deterministic differential equations representing the immune cells involved in an HIV-1 and Mtb co-infected individual. Results show that although the non-lytic arm of the HIV-1 cytotoxic T-cells affects the co-infection dynamics more than the lytic factors, a combination of both factors results in a more positive reduced progression to the AIDS state. This is due to the increased protection of the CD4<sup>+</sup> T-cells by the CTL mechanisms by further reducing infections and replications by the HIV. Thus, HIV-1 specific CTLs mechanisms’ involvement is here recommended to be part of a solution to the HIV and Mtb co-infection problems. 展开更多
关键词 Mycobacterium tuberculosis HIV CO-INFECtION cytotoxic t-Cells Lytic and Non-Lytic Factors
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Relationship between serum HBV DNA level and HBV-specific, nonspecific cytotoxic T lymphocytes and natural killer cells in patients with chronic hepatitis B 被引量:23
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作者 GU Xi-bing YANG Xiao-juan WANG Dong HUA Zhong XU Yue-qin LU Zhong-hua 《Chinese Medical Journal》 SCIE CAS CSCD 2009年第18期2129-2132,共4页
Background The response of patients with chronic hepatitis B (CHB) to antiviral therapy against hepatitis B virus (HBV) is related to the base line level of HBV DNA, but the mechanism is not clear. The present stu... Background The response of patients with chronic hepatitis B (CHB) to antiviral therapy against hepatitis B virus (HBV) is related to the base line level of HBV DNA, but the mechanism is not clear. The present study aimed to understand the possible relationship between the level of HBV DNA and HBV-specific, nonspecific cytotoxic T lymphocytes (CTL) and natural killer (NK) cells of CHB patients and the mechanism how the HBV DNA level influences the antiviral therapeutic effect. Methods Totally 100 adult patients with CHB who were positive for HBV DNA, HBeAg and (HLA)-A2 were enrolled into this study. HBV DNA was tested by real time fluorescence quantitative polymerase chain reaction (PCR). HBV specific and nonspecific CTL and NK cells were tested by flowcytometry. Serum alanine aminotransferase (ALT) and total bilirubin (TBil) were determined for each patient using routine biochemical tests. The 100 cases were assigned to two groups based on their HBV DNA level: group A had 48 cases, their HBV DNA level was 104-105 copies/ml, group B had 52 cases their HBV DNA level was 106-107 copies/ml. HBV specific CTL, nonspecific CTL, NK cells, ALT and TBil of the two groups were compared. Results HBV DNA level of groups A and B was (4.81±0.39) log10 copies/ml and (6.81±0.40) log10 copies/ml, respectively (t=25.32, P 〈0.001). HBV specific CTL and NK cells of group A were significantly higher than those of group B (P 〈0.001 for both). Nonspecific CTL of group A was significantly lower than that of group B (P 〈0.01). ALT and TBil of group A were significantly lower than those of group B (P 〈0.01 and P 〈0.05, respectively). Conclusions Serum HBV DNA level of patients with CHB is related to HBV specific CTL, nonspecific CTL and NK cells, which might result in inflammatory reaction of liver and cause more damage to liver function. Mechanism of HBV DNA level affecting the efficacy of anti-viral treatment may be related to the levels of HBV specific CTL and NK cells. 展开更多
关键词 chronic hepatitis B HBV DNA cytotoxic t lymphocyte liver function NK cells
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Analysis of Epstein-Barr viral DNA load, EBV-LMP2 specific cytotoxic T-lymphocytes and levels of CD4^+CD25^+ T ceils in patients with nasopharyngeal carcinomas positive for IgA antibody to EBV viral capsid antigen 被引量:15
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作者 MO Wu-ning TANG An-zhou +3 位作者 ZHOU Ling HUANG Guang-wu WANG Zhan ZENG Yi 《Chinese Medical Journal》 SCIE CAS CSCD 2009年第10期1173-1178,共6页
Background Epstein-Barr virus (EBV) is a herpesvirus commonly associated with several malignant diseases including nasopharyngeal carcinoma (NPC), which is a common cancer in Southeastern Asia. Previous studies sh... Background Epstein-Barr virus (EBV) is a herpesvirus commonly associated with several malignant diseases including nasopharyngeal carcinoma (NPC), which is a common cancer in Southeastern Asia. Previous studies showed that plasma levels of EBV-DNA might be a sensitive and reliable biomarker for the diagnosis, staging and evaluating of therapy for NPC. There are a few analyses of the levels of EBV-latent membrane protein 2 (LMP2)-specific cytotoxic T-lymphocytes (CTLs) in patients with NPC. This study was conducted to investigate the levels of EBV-LMP2-specific CTLs, EBV-DNA load and the level of CD4^+CD25^+T cells in such patients. Methods From February 2006 to April 2006, 62 patients with NPC, 40 healthy virus carriers positive for EBV viral capsid antigen (EBV-IgA-VCA) and 40 controls were enrolled in the study. We used a highly sensitive ELISPOT assay, real-time polymerase chain reaction (PCR) and flow cytometry to measure the EBV-LMP2-specific CTL response, the EBV DNA load and the level of CD4^+CD25^+T cells, respectively. Results The EBV-LMP2-specific CTL responses of the samples from the control, healthy virus carriers and patients with NPC were significantly different from the LMP2 epitopes, with the control and healthy virus carrier samples displaying a stronger response in three cases. There were significant differences in EBV DNA load in serum between NPC and the healthy groups; patients with NPC at stages Ⅲ or Ⅳ had significantly higher viral loads compared with those at stages Ⅰ or Ⅱ. A significantly higher percentage of CD4^+CD25^+ T lymphocytes were detected in the patients, compared with healthy virus carriers and healthy controls. Moreover, patients with advanced stages of NPC (Ⅲ and Ⅳ) had significantly higher percentages than the patients with early stages (Ⅰ and Ⅱ). Conclusions Patients with NPC are frequently unable to establish or maintain sufficient immunosurveillance to control proliferating B cells harboring EBV and to destroy the tumor cells that express immunodominant LMP2 proteins. Controlling the activity of CD4^+CD25^+T cells and elevating CD8^+ cells specific for LMP2 epitopes could be an effective immunotherapy for patients with NPC. 展开更多
关键词 nasopharyngeal carcinoma cell immunity Epstein-Barr virus latent membrane protein 2 cytotoxic t lymphocyte
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Effect of oxymatrine on specific cytotoxic T lymphocyte surface programmed death receptor-1 expression in patients with chronic hepatitis B 被引量:11
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作者 GU Xi-bing YANG Xiao-juan +7 位作者 HUA Zhong LU Zhong-hua ZHANG Bo ZHU Yin-fang WU Hang-yuan JIANG Yi-ming CHEN Hao-kun PEI Hao 《Chinese Medical Journal》 SCIE CAS CSCD 2012年第8期1434-1438,共5页
Background Oxymatrine has certain antiviral effects in the treatment of chronic hepatitis B (CHB), but its exact mechanism is unclear. The objective of the present study was to explore oxymatrine's antiviral mechan... Background Oxymatrine has certain antiviral effects in the treatment of chronic hepatitis B (CHB), but its exact mechanism is unclear. The objective of the present study was to explore oxymatrine's antiviral mechanism by studying its effect on the hepatitis B virus (HBV) specific cytotoxic T lymphocyte (CTL) surface programmed death receptor-1 (PD-1) expression in CHB patients. Methods Sixty-five CHB patients who had HBV DNA≥104 copies/mL positive HBeAg, positive human leukocyte antigen (HLA)-A2, alanine aminotransferase (ALT) 〉2xupper limit of normal value (ULN) were randomly divided into two groups: treatment group (n=33), treated with an intravenous infusion of 600 mg oxymatrine in glucose solution once a day for a month, then with a 200 mg oxymatrine oral capsule three times a day, and a 200 mg silibin meglumine tablet three times a day; control group (n=32) patients were treated only with silibin meglumine tablet, method and dosage were the same as those of treatment group. Three months later, peripheral blood HBV-specific CTL surface PD-1 expression, HBV-specific CTL level, HBV DNA, HBeAg, and results of liver function tests were analyzed and compared. Results Three months post-treatment, in the treatment group, peripheral blood HBV-specific CTL surface PD-1 expression ((19.42±15.94)%) decreased significantly compared to the pretreatment level ((31.30±24.06)%; P 〈0.05), and decreased significantly compared to that of control group three months after treatment ((29.45±21.62)%; P 〈0.05). HBV-specific CTL level ((0.42±0.07)%) significantly increased compared with the pretreatment ((0.29±0.15)%; P 〈0.01), and the control group posttreatment level was (0.31±0.15)% (P 〈0.05). HBV DNA level in 11 cases became negative (HBV DNA〈500 copies/ml, 33.33%), which was higher than that of the control group after treatment (two cases, 6.25%; X2=7.45, P 〈0.01), HBeAg of nine cases turned negative (27.27%), which was higher than that of the control group after treatment (one case, 3.13%; X2=7.27, P 〈0.01). Conclusion Oxymatrine could downregulate peripheral blood HBV-specific CTL surface PD-1 expression in CHB patients, increase HBV-specific CTL level, which may be one of the possible mechanisms by which oxymatrine clears or inhibits HBV in CHB Datients. 展开更多
关键词 OXYMAtRINE chronic hepatitis B programmed death receptor-l cytotoxic t lymphocytes
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Activated cytotoxic lymphocytes promote tumor progression by increasing the ability of 3LL tumor cells to mediate MDSC chemoattraction via Fas signaling 被引量:6
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作者 Fei Yang Yinxiang Wei +8 位作者 Zhijian Cai Lei Yu Lingling Jiang Chengyan Zhang Huanmiao Yan Qingqing Wang Xuetao Cao Tingbo Liang Jianli Wang 《Cellular & Molecular Immunology》 SCIE CAS CSCD 2015年第1期66-76,共11页
The Fas/FasL system transmits intracellular apoptotic signaling, inducing cell apoptosis. However, Fas signaling also exerts non-apoptotic functions in addition to inducing tumor cell apoptosis. For example, Fas signa... The Fas/FasL system transmits intracellular apoptotic signaling, inducing cell apoptosis. However, Fas signaling also exerts non-apoptotic functions in addition to inducing tumor cell apoptosis. For example, Fas signaling induces lung cancer tumor cells to produce prostaglandin E2 (PGE2) and recruit myeloid-derived suppressor cells (MDSCs). Activated cytotoxic T lymphocytes (CTLs) induce and express high levels of FasL, but the effects of Fas activation initiated by FasL in CTLs on apoptosis-resistant tumor cells remain largely unclear. We purified activated CD8^+ T cells from OT-1 mice, evaluated the regulatory effects of Fas activation on tumor cell escape and investigated the relevant mechanisms. We found that CTLs induced tumor cells to secrete PGE2 and increase tumor cell-mediated chemoattraction of MDSCs via Fas signaling, which was favorable to tumor growth. Our results indicate that CTLs may participate in the tumor immune evasion process. To the best of our knowledge, this is a novel mechanism by which CTLs play a role in tumor escape. Our findings implicate a strategy to enhance the antitumor immune response via reduction of negative immune responses to tumors promoted by CTLs through Fas signaling. 展开更多
关键词 activated cytotoxic t lymphocytes FAS/FASL myeloid-derived suppressor cells prostaglandin E2 tumor escape
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