《HIV-1病毒血症阻止具有增殖活性,能产生白介素2的HIV特异性CD4阳性记忆T细胞的建立》

  • 来源专题:艾滋病防治
  • 编译者: 李越
  • 发布时间:2005-04-15
  • CD4+ T cell responses are associated with disease control in chronic viral infections. We analyzed human immunodeficiency virus (HIV)-specific responses in ten aviremic and eight viremic patients treated during primary HIV-1 infection and for up to 6 yr thereafter. Using a highly sensitive 5-(and-6)-carboxyfluorescein diacetate-succinimidyl ester–based proliferation assay, we observed that proliferative Gag and Nef peptide-specific CD4+ T cell responses were 30-fold higher in the aviremic patients. Two subsets of HIV-specific memory CD4+ T cells were identified in aviremic patients, CD45RA- CCR7+ central memory cells (Tcm) producing exclusively interleukin (IL)-2, and CD45RA- CCR7- effector memory cells (Tem) that produced both IL-2 and interferon (IFN)-. In contrast, in viremic, therapy-failing patients, we found significant frequencies of Tem that unexpectedly produced exclusively IFN-. Longitudinal analysis of HIV epitope–specific CD4+ T cells revealed that only cells that had the capacity to produce IL-2 persisted as long-term memory cells. In viremic patients the presence of IFN-–producing cells was restricted to periods of elevated viremia. These findings suggest that long-term CD4+ T cell memory depends on IL-2–producing CD4+ T cells and that IFN- only–producing cells are short lived. Our data favor a model whereby competent HIV-specific Tcm continuously arise in small numbers but under persistent antigenemia are rapidly induced to differentiate into IFN- only–producing cells that lack self-renewal capacity.
  • 原文来源:http://www.jem.org/cgi/reprint/198/12/1909
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    • 来源专题:艾滋病防治
    • 编译者:门佩璇
    • 发布时间:2015-07-13
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    • 来源专题:艾滋病防治
    • 编译者:李越
    • 发布时间:2005-04-14
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