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
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.