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
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 "ALAHGVRAL (core 150-158)". 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
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
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
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
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
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
BACKGROUND At present,immune checkpoint inhibitors(ICIs)remain the 1st-line therapy me-thod for patients suffering from high microsatellite instability/deficient misma-tch repair metastatic colorectal cancer(mCRC).How...BACKGROUND At present,immune checkpoint inhibitors(ICIs)remain the 1st-line therapy me-thod for patients suffering from high microsatellite instability/deficient misma-tch repair metastatic colorectal cancer(mCRC).However,ICI treatments demon-strate minimal therapeutic efficacy against microsatellite stable(MSS)/proficient mismatch repair(pMMR)CRC.This is mainly because this type of tumor is a“cold tumor”with almost no lymphocyte infiltration.Anti-angiogenic drugs have been found to improve the immune microenvironment by promoting many immune cells to enter the immune microenvironment,thereby exerting anti-tumor effects.AIM To investigate the effects of ICIs combined with bevacizumab monoclonal anti-body on tumor immune cells in MSS/pMMR advanced CRC patients with first-line treatment failure.METHODS A total of 110 MSS/pMMR patients with advanced CRC after first-line treatment failure in the Affiliated Hospital of Qinghai University were enrolled for a ran-domized controlled trial.In short,patients in the experimental group(n=60)were given sintilimab plus bevacizumab for 4 cycles,and those in the control group(n=50)patients were treated with FOLFIRI combined with bevacizumab for 4 cycles.The expression levels of cluster of differentiation(CD)8(+)T cells,tumor-associated macrophages(TAMs),and cancer-associated fibroblasts(CAFs)were comprehensively evaluated to assess the effects of sintilimab combined with bevacizumab on MSS/pMMR advanced CRC sufferers following failure of 1st-line therapy.RESULTS The positive expression rates of CD8(+)T lymphocytes(30%vs 50%),TAMs(23.30%vs 60%),and CAFs(23.30%vs 50%)before and after treatment in both groups exhibited statistical significance(P<0.05).Additionally,the therapeutic effects of both groups(partial remission:26.67%vs 10%;objective response rate:26.70%vs 10%)were significantly different(P<0.05).Although the experimental group showed a higher progression-free survival,median progression-free survival,and disease control rate than the control group,the difference was not statist-ically significant.Moreover,no significant difference in the occurrence rate of drug-related adverse reactions after treatment between the two groups was found(P>0.05).CONCLUSION ICIs in combination with bevacizumab can not only improve the patient’s prognosis but also yield safe and controllable adverse drug reactions in patients suffering from MSS/pMMR advanced CRC after failure to a 1st-line therapy.展开更多
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
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
MUC1 is an antigen that is overexpressed on the cell surface of many human breast adenocarcinomas and other types of cancer. The cancer immunity cycle has seven steps, starting with release of cancer cell antigen and ...MUC1 is an antigen that is overexpressed on the cell surface of many human breast adenocarcinomas and other types of cancer. The cancer immunity cycle has seven steps, starting with release of cancer cell antigen and following with cancer antigen presentation. Priming, activation and trafficking of T cells to tumors are the next steps and the infiltration of T cells into tumors, the recognition of cancer cells by T cells and killing of cancer cells are the final steps. We have tested a synthetic peptide for the MUC1 antigen and generated dendritic cells (DCs) that were pulsed with the specific peptide. Mature DCs were used to activate naive T cells to differentiate into antigen-specific CTLs. CTLs were tested for proliferation, cytokine release (IFNγ), activation markers and cytotoxicity against human breast adenocarcinoma cell lines. The cytotoxic effect of those CTLs was higher against MCF7 human cell line than against MDA-MB-231 human cell line.展开更多
Objective: To study the expression of Fas and Bcl-2proteins on T lymphocyte subsets in the peripheralblood of relapsing patients with condyloma acuminatum(CA) and healthy controls. Methods: Flow cytometry (permeabizat...Objective: To study the expression of Fas and Bcl-2proteins on T lymphocyte subsets in the peripheralblood of relapsing patients with condyloma acuminatum(CA) and healthy controls. Methods: Flow cytometry (permeabization andstaining procedure with conjugated antibodies) wasused. Results: We observed that the expression of Fasprotein on CD4^+ T lymphocyte subset of CA patientswas significantly higher than that of healthy controls(P<0.01). Conclusions: Increased expression of Fas proteinon CD4^+ T lymphocyte subset may be a cause of de-creased percentage of CD4^+ T lymphocyte subset. Thisinduces the increased ratio of CD4^+/CD8^+.展开更多
基金Supported by the Science & Technology Foundation for Academicians of Zhejiang Province, China, No. 203201513
文摘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.
基金the National Nature Science Foundation of China,No.39800121
文摘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 "ALAHGVRAL (core 150-158)". 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.
基金supported by grants from the National Key Basic Research Program of China (No.20014CB510008,No.2005CB522901)the National Natural Sciences Foundation of China (No.30400412)
文摘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.
基金supported by a grant from the Medical Research Projects of Hainan Health Department(grant number 2013-009)Science and Technology Funding Project of Guangzhou,China(Grant No.201604020009)
文摘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.
基金Supported by National Natural Science Foundation of China,No.81071982
文摘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.
文摘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.
基金supported by National Natural Science Foundation(No.81260315)Foundation of the Education Department of Guangxi Province,China(No.201010LX375)the Foundation of the Nature Science Fund,Guangxi Province,China(No.2012GXNSFBA053121)
文摘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.
基金Supported by the 2021 Key Topic of the Qinghai Provincial Health System-Guiding Plan Topic,No.2021-WJZDX-43.
文摘BACKGROUND At present,immune checkpoint inhibitors(ICIs)remain the 1st-line therapy me-thod for patients suffering from high microsatellite instability/deficient misma-tch repair metastatic colorectal cancer(mCRC).However,ICI treatments demon-strate minimal therapeutic efficacy against microsatellite stable(MSS)/proficient mismatch repair(pMMR)CRC.This is mainly because this type of tumor is a“cold tumor”with almost no lymphocyte infiltration.Anti-angiogenic drugs have been found to improve the immune microenvironment by promoting many immune cells to enter the immune microenvironment,thereby exerting anti-tumor effects.AIM To investigate the effects of ICIs combined with bevacizumab monoclonal anti-body on tumor immune cells in MSS/pMMR advanced CRC patients with first-line treatment failure.METHODS A total of 110 MSS/pMMR patients with advanced CRC after first-line treatment failure in the Affiliated Hospital of Qinghai University were enrolled for a ran-domized controlled trial.In short,patients in the experimental group(n=60)were given sintilimab plus bevacizumab for 4 cycles,and those in the control group(n=50)patients were treated with FOLFIRI combined with bevacizumab for 4 cycles.The expression levels of cluster of differentiation(CD)8(+)T cells,tumor-associated macrophages(TAMs),and cancer-associated fibroblasts(CAFs)were comprehensively evaluated to assess the effects of sintilimab combined with bevacizumab on MSS/pMMR advanced CRC sufferers following failure of 1st-line therapy.RESULTS The positive expression rates of CD8(+)T lymphocytes(30%vs 50%),TAMs(23.30%vs 60%),and CAFs(23.30%vs 50%)before and after treatment in both groups exhibited statistical significance(P<0.05).Additionally,the therapeutic effects of both groups(partial remission:26.67%vs 10%;objective response rate:26.70%vs 10%)were significantly different(P<0.05).Although the experimental group showed a higher progression-free survival,median progression-free survival,and disease control rate than the control group,the difference was not statist-ically significant.Moreover,no significant difference in the occurrence rate of drug-related adverse reactions after treatment between the two groups was found(P>0.05).CONCLUSION ICIs in combination with bevacizumab can not only improve the patient’s prognosis but also yield safe and controllable adverse drug reactions in patients suffering from MSS/pMMR advanced CRC after failure to a 1st-line therapy.
文摘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.
基金This work was supported by grants from the National Natural Science Foundation of China (No. 39970322).
文摘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.
文摘MUC1 is an antigen that is overexpressed on the cell surface of many human breast adenocarcinomas and other types of cancer. The cancer immunity cycle has seven steps, starting with release of cancer cell antigen and following with cancer antigen presentation. Priming, activation and trafficking of T cells to tumors are the next steps and the infiltration of T cells into tumors, the recognition of cancer cells by T cells and killing of cancer cells are the final steps. We have tested a synthetic peptide for the MUC1 antigen and generated dendritic cells (DCs) that were pulsed with the specific peptide. Mature DCs were used to activate naive T cells to differentiate into antigen-specific CTLs. CTLs were tested for proliferation, cytokine release (IFNγ), activation markers and cytotoxicity against human breast adenocarcinoma cell lines. The cytotoxic effect of those CTLs was higher against MCF7 human cell line than against MDA-MB-231 human cell line.
文摘Objective: To study the expression of Fas and Bcl-2proteins on T lymphocyte subsets in the peripheralblood of relapsing patients with condyloma acuminatum(CA) and healthy controls. Methods: Flow cytometry (permeabization andstaining procedure with conjugated antibodies) wasused. Results: We observed that the expression of Fasprotein on CD4^+ T lymphocyte subset of CA patientswas significantly higher than that of healthy controls(P<0.01). Conclusions: Increased expression of Fas proteinon CD4^+ T lymphocyte subset may be a cause of de-creased percentage of CD4^+ T lymphocyte subset. Thisinduces the increased ratio of CD4^+/CD8^+.