Epstein-Barr virus （EBV） associated nasopharyngeal carcinoma （NPC） is a high incidence tumor in Southeast Asia. Among EBV encoded proteins, latent membrane protein 2A （LMP2A） is an important antigen for T cell t...Epstein-Barr virus （EBV） associated nasopharyngeal carcinoma （NPC） is a high incidence tumor in Southeast Asia. Among EBV encoded proteins, latent membrane protein 2A （LMP2A） is an important antigen for T cell therapy of EBV. In this study, we predicted six HLA-A2 restricted CTL candidate epitopes of LMP2A by SYFPEITHI, NetMHC and MHCPred methods combined with the polynomial method. Subsequently, biological functions of these peptides were tested by experiments in vitro. In ELISPOT assay, the positive response of the LMP2A specific CTL stimulated by three （LMP2A264.272, LMP2A426-434 and LMP2A3s6.364） of six peptides respectively showed that the numbers of spots forming cells （SFC） ranged from 55.7 to 80.6 SFC/5 x 104 CO8^＋ T cells and the responding index （RI） ranged from 5.4 to 7. These three epitope-specific CTLs could effectively kill specific HLA-A2- expressing target cells. As a result, LMP2A264.272 （QLSPLLGAV）, LMP2A426.434 （CLGGLLTMV） and LMP2A356.364 （FLYALALLL） were identified as LMP2A-specific CD8^＋ T-cell epitopes. It would be useful to clarify immune response toward EBV and to develop a vaccine against EBV-correlative NPC.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
AIM: To predict the HLA-A2-restricted CTL epitopes of tumor antigens associated with hepatocellular carcinoma (HCC).METHODS: MAGE-1, MAGE-3, MAGE-8, P53 and AFP were selected as objective antigens in this study for th...AIM: To predict the HLA-A2-restricted CTL epitopes of tumor antigens associated with hepatocellular carcinoma (HCC).METHODS: MAGE-1, MAGE-3, MAGE-8, P53 and AFP were selected as objective antigens in this study for the close association with HCC. The HLA-A*0201 restricted CTL epitopes of objective tumor antigens were predicted by SYFPEITHI prediction method combined with the polynomial quantitative motifs method. The threshold of polynomial scores was set to -24.RESULTS: The SYFPEITHI prediction values of all possible nonamers of a given protein sequence were added together and the ten high-scoring peptides of each protein were chosen for further analysis in primary prediction. Thirtyfive candidates of CTL epitopes (nonamers) derived from the primary prediction results were selected by analyzing with the polynomial method and compared with reported CTL epitopes.CONCLUSION: The combination of SYFPEITHI prediction method and polynomial method can improve the prediction efficiency and accuracy. These nonamers may be useful in the design of therapeutic peptide vaccine for HCC and as immunotherapeutic strategies against HCC after identified by immunology experiment.展开更多
基金supported by the National Nature Science Foundation of China (No.30571715)
文摘Epstein-Barr virus （EBV） associated nasopharyngeal carcinoma （NPC） is a high incidence tumor in Southeast Asia. Among EBV encoded proteins, latent membrane protein 2A （LMP2A） is an important antigen for T cell therapy of EBV. In this study, we predicted six HLA-A2 restricted CTL candidate epitopes of LMP2A by SYFPEITHI, NetMHC and MHCPred methods combined with the polynomial method. Subsequently, biological functions of these peptides were tested by experiments in vitro. In ELISPOT assay, the positive response of the LMP2A specific CTL stimulated by three （LMP2A264.272, LMP2A426-434 and LMP2A3s6.364） of six peptides respectively showed that the numbers of spots forming cells （SFC） ranged from 55.7 to 80.6 SFC/5 x 104 CO8^＋ T cells and the responding index （RI） ranged from 5.4 to 7. These three epitope-specific CTLs could effectively kill specific HLA-A2- expressing target cells. As a result, LMP2A264.272 （QLSPLLGAV）, LMP2A426.434 （CLGGLLTMV） and LMP2A356.364 （FLYALALLL） were identified as LMP2A-specific CD8^＋ T-cell epitopes. It would be useful to clarify immune response toward EBV and to develop a vaccine against EBV-correlative NPC.
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 Natural Scientific Foundation of China, No. 39830420
文摘AIM: To predict the HLA-A2-restricted CTL epitopes of tumor antigens associated with hepatocellular carcinoma (HCC).METHODS: MAGE-1, MAGE-3, MAGE-8, P53 and AFP were selected as objective antigens in this study for the close association with HCC. The HLA-A*0201 restricted CTL epitopes of objective tumor antigens were predicted by SYFPEITHI prediction method combined with the polynomial quantitative motifs method. The threshold of polynomial scores was set to -24.RESULTS: The SYFPEITHI prediction values of all possible nonamers of a given protein sequence were added together and the ten high-scoring peptides of each protein were chosen for further analysis in primary prediction. Thirtyfive candidates of CTL epitopes (nonamers) derived from the primary prediction results were selected by analyzing with the polynomial method and compared with reported CTL epitopes.CONCLUSION: The combination of SYFPEITHI prediction method and polynomial method can improve the prediction efficiency and accuracy. These nonamers may be useful in the design of therapeutic peptide vaccine for HCC and as immunotherapeutic strategies against HCC after identified by immunology experiment.
