Fleischer B, Schrezenmeier H, Wagner H
J Immunol. 1986 Mar 1;136(5):1625-8.
The function of the T cell differentiation antigens CD4 (Leu-3/T4) and CD8 (Leu-2/T8) on human cytotoxic T lymphocytes (CTL) is presently seen only in conjugate formation between CTL and target cell via class II or class I MHC antigens rather than in the later killing steps. In this study, human CD4+ and CD8+ CTL clones were used to investigate the effects of monoclonal antibodies against these differentiation antigens on nonspecific triggering of cytotoxicity. Cytotoxicity was induced either by antibodies against the CD3 (T3) antigen or by the lectins Con A and PHA. Anti-CD4 or anti-CD8 antibodies specifically inhibited all types of cytotoxicity of CD4+ or CD8+ CTL, respectively, regardless of the specificity of the CTL for class I or class II HLA antigens and regardless of whether target cells expressed class I or class II antigens. These results are incompatible with an exclusive role of the CD4 and CD8 molecules in MHC class recognition and are discussed with respect to a function as negative signal receptors for these molecules on CTL.
T细胞分化抗原CD4（Leu-3/T4）和CD8（Leu-2/T8）在人细胞毒性T淋巴细胞（CTL）上的功能，目前仅在CTL与靶细胞通过II类或I类MHC抗原形成共轭时可见，而非在后续的杀伤步骤中。在本研究中，使用人CD4⁺和CD8⁺CTL克隆来研究针对这些分化抗原的单克隆抗体对细胞毒性非特异性触发的影响。细胞毒性通过抗CD3（T3）抗原的抗体或凝集素刀豆蛋白A和PHA诱导。抗CD4或抗CD8抗体分别特异性抑制CD4⁺或CD8⁺CTL的所有类型细胞毒性，无论CTL对I类或II类HLA抗原的特异性如何，也无论靶细胞是否表达I类或II类抗原。这些结果与CD4和CD8分子在MHC类识别中的唯一作用不相符，并就这些分子作为CTL上的负信号受体的功能进行了讨论。
