The 8^th International Workshop on Human Leucocyte Differentiation Antigens （chaired by HZ and managed by BS） was run over a 4-year period and culminated in a conference in December 2004. Here we review the achievem...The 8^th International Workshop on Human Leucocyte Differentiation Antigens （chaired by HZ and managed by BS） was run over a 4-year period and culminated in a conference in December 2004. Here we review the achievements of the HLDA Workshops and provide links to information on CD molecules and antibodies against them, including the 93 new CDs assigned in the 8^th Workshop. We consider what remains to be achieved （including an estimate of the number of leucocyte surface molecules still to be discovered）, and how the field can best move forward.展开更多
Background The mechanism of chronic immune activation and impairment of HIV-specific immune responses during chronic infection is not fully understood. However, it is known that high immune activation leads to more ra...Background The mechanism of chronic immune activation and impairment of HIV-specific immune responses during chronic infection is not fully understood. However, it is known that high immune activation leads to more rapid progression to AIDS. We hypothesize that CD4^＋ T cell-mediated viral antigen presentation contributes to this pathologic immune activation in HIV-infected individuals. Methods HIV-specific T cells, responding to noninfectious HIV-1 virions as antigen, were measured by flow cytometric assays. These experimental conditions reflect the in vivo condition where noninfectious HIV-1 represents more than 99% of the antigens. Results CD4^＋ T cells purified from HIV-infected individuals were capable of cross presenting exogenous noninfectious HIV-1 virions to HIV-1-specific CD8^＋ T cells. Cross presentation required the entry of HIV-1 to CD4^＋ T cells and antigen translocation from endoplasmic reticulum to the Golgi complex. Blocking CD4^＋ mediated activation of HIV-specific CD8^＋ T cells and redirecting the viral antigens to antigen presenting cells improved HIV-specific T cell responses. Contusions One possible cause of chronic immune activation and impairment of HIV-1 specific T cell responses is represented by HIV-1 harboring CD4^＋ T cells cross presenting HIV-1 antigen to activate CD8^＋ T cells. This new mechanism provides the first evidence that cross presentation of noninfectious HIV-1 virions play a role in the immunopathogenesis of HIV-1 infection.展开更多
AIM: To prepare a cancer vaccine (H(22)-DC) expressing high levels of costimulatory molecules based on fusions of hepatocarcinoma cells (H(22)) with dendritic cells (DC) of mice and to analyze the biological character...AIM: To prepare a cancer vaccine (H(22)-DC) expressing high levels of costimulatory molecules based on fusions of hepatocarcinoma cells (H(22)) with dendritic cells (DC) of mice and to analyze the biological characteristics and induction of specific CTL activity of H(22)-DC. METHODS: DCs were isolated from murine spleen by metrizamide density gradient centrifugation, purified based on its characteristics of semi-adhesion to culture plates and FcR-,and were cultured in the medium containing GM-CSF and IL-4. A large number of DC were harvested. DCs were then fused with H(22) cells by PEG and the fusion cells were marked with CD11c MicroBeads. The H(22)-DC was sorted with Mimi MACS sorter. The techniques of cell culture, immunocytochemistry and light microscopy were also used to test the characteristics of growth and morphology of H(22)-DC in vitro. As the immunogen, H(22)-DC was inoculated subcutaneously into the right armpit of BALB/C mice, and their tumorigenicity in vivo was observed. MTT was used to test the CTL activity of murine spleen in vivo. RESULTS: DC cells isolated and generated were CD11c+ cells with irregular shape, and highly expressed CD80, CD86 and CD54 molecules. H22 cells were CD11c- cells with spherical shape and bigger volume, and did not express CD80, CD86 and CD54 molecules.H(22)-DC was CD11c+ cells with bigger volume, being spherical, flat or irregular in shape, and highly expressed CD80, CD86 and CD54 molecules, too. H(22)-DC was able to divide and proliferate in vitro, but its activity of proliferation was significantly decreased as compared with H(22) cells and its growth curve was flatter than H(22) cells. After subcutaneous inoculation over 60 days, H(22)-DC showed no tumorigenecity in mice, which was significantly different from control groups (P【0.01). The spleen CTL activity against H(22) cells in mice implanted with fresh H(22)-DC was significantly higher than control groups (P 【 0.01). CONCLUSION: H(22)-DC could significantly stimulate the specific CTL activity of murine spleen, which suggests that the fusion cells have already obtained the function of antigen presenting of parental DC and could present H(22)specific antigen which has not been identified yet, and H(22)-DC could induce antitumor immune response; although simply mixed H(22) cells with DC could stimulate the specific CTL activity which could inhibit the growth of tumor in some degree, it could not prevent the generation of tumor. It shows that the DC vaccine is likely to become a helpful approach in immunotherapy of hepatocarcinoma.展开更多
文摘The 8^th International Workshop on Human Leucocyte Differentiation Antigens （chaired by HZ and managed by BS） was run over a 4-year period and culminated in a conference in December 2004. Here we review the achievements of the HLDA Workshops and provide links to information on CD molecules and antibodies against them, including the 93 new CDs assigned in the 8^th Workshop. We consider what remains to be achieved （including an estimate of the number of leucocyte surface molecules still to be discovered）, and how the field can best move forward.
基金This study was supported by a grant from the Major Basic Project of China (973) (No. 2005CB522903).
文摘Background The mechanism of chronic immune activation and impairment of HIV-specific immune responses during chronic infection is not fully understood. However, it is known that high immune activation leads to more rapid progression to AIDS. We hypothesize that CD4^＋ T cell-mediated viral antigen presentation contributes to this pathologic immune activation in HIV-infected individuals. Methods HIV-specific T cells, responding to noninfectious HIV-1 virions as antigen, were measured by flow cytometric assays. These experimental conditions reflect the in vivo condition where noninfectious HIV-1 represents more than 99% of the antigens. Results CD4^＋ T cells purified from HIV-infected individuals were capable of cross presenting exogenous noninfectious HIV-1 virions to HIV-1-specific CD8^＋ T cells. Cross presentation required the entry of HIV-1 to CD4^＋ T cells and antigen translocation from endoplasmic reticulum to the Golgi complex. Blocking CD4^＋ mediated activation of HIV-specific CD8^＋ T cells and redirecting the viral antigens to antigen presenting cells improved HIV-specific T cell responses. Contusions One possible cause of chronic immune activation and impairment of HIV-1 specific T cell responses is represented by HIV-1 harboring CD4^＋ T cells cross presenting HIV-1 antigen to activate CD8^＋ T cells. This new mechanism provides the first evidence that cross presentation of noninfectious HIV-1 virions play a role in the immunopathogenesis of HIV-1 infection.
基金Supported jby the Natural Science Foundation of Guangdong Province China,No.980180
文摘AIM: To prepare a cancer vaccine (H(22)-DC) expressing high levels of costimulatory molecules based on fusions of hepatocarcinoma cells (H(22)) with dendritic cells (DC) of mice and to analyze the biological characteristics and induction of specific CTL activity of H(22)-DC. METHODS: DCs were isolated from murine spleen by metrizamide density gradient centrifugation, purified based on its characteristics of semi-adhesion to culture plates and FcR-,and were cultured in the medium containing GM-CSF and IL-4. A large number of DC were harvested. DCs were then fused with H(22) cells by PEG and the fusion cells were marked with CD11c MicroBeads. The H(22)-DC was sorted with Mimi MACS sorter. The techniques of cell culture, immunocytochemistry and light microscopy were also used to test the characteristics of growth and morphology of H(22)-DC in vitro. As the immunogen, H(22)-DC was inoculated subcutaneously into the right armpit of BALB/C mice, and their tumorigenicity in vivo was observed. MTT was used to test the CTL activity of murine spleen in vivo. RESULTS: DC cells isolated and generated were CD11c+ cells with irregular shape, and highly expressed CD80, CD86 and CD54 molecules. H22 cells were CD11c- cells with spherical shape and bigger volume, and did not express CD80, CD86 and CD54 molecules.H(22)-DC was CD11c+ cells with bigger volume, being spherical, flat or irregular in shape, and highly expressed CD80, CD86 and CD54 molecules, too. H(22)-DC was able to divide and proliferate in vitro, but its activity of proliferation was significantly decreased as compared with H(22) cells and its growth curve was flatter than H(22) cells. After subcutaneous inoculation over 60 days, H(22)-DC showed no tumorigenecity in mice, which was significantly different from control groups (P【0.01). The spleen CTL activity against H(22) cells in mice implanted with fresh H(22)-DC was significantly higher than control groups (P 【 0.01). CONCLUSION: H(22)-DC could significantly stimulate the specific CTL activity of murine spleen, which suggests that the fusion cells have already obtained the function of antigen presenting of parental DC and could present H(22)specific antigen which has not been identified yet, and H(22)-DC could induce antitumor immune response; although simply mixed H(22) cells with DC could stimulate the specific CTL activity which could inhibit the growth of tumor in some degree, it could not prevent the generation of tumor. It shows that the DC vaccine is likely to become a helpful approach in immunotherapy of hepatocarcinoma.
