Leeuwenberg J F, Spits H, Tax W J, Capel P J
J Immunol. 1985 Jun;134(6):3770-5.
The effects of monoclonal anti-T3 antibodies on the effector phase of cytotoxic T lymphocytes (CTL) were studied with respect to antigen-specific and antigen-nonspecific lysis of different target cells. Anti-T3 antibodies inhibited the antigen-specific lysis by CTL generated in mixed lymphocyte cultures (MLC), but they concomitantly augmented the nonspecific killing of third-party cells such as the cell lines Daudi, Raji, and K562. This nonspecific cytotoxicity was induced by various anti-T3 antibodies, whereas antibodies reactive with other antigens expressed on the cytotoxic effector cells lacked any such activity. Anti-T3 antibodies induced nonspecific cytotoxicity only when activated T cells, obtained by primary MLC, by repeated restimulation, or after cloning, were used. The antibodies had no effect on unstimulated peripheral T lymphocytes or thymocytes. The inhibition of the antigen-specific lysis and the induction of nonspecific lysis by anti-T3 was dose dependent, and both effects occurred at the same concentration range of anti-T3. F(ab')2 fragments of anti-T3 inhibited the specific lysis but were not able to induce cytotoxic activity, indicating that this induction is an Fc-dependent process. When different target cells were tested, only Fc receptor-positive cells were susceptible for this nonspecific cytotoxicity. Thus, anti-T3 antibodies have a dual effect on effector CTL: they inhibit antigen-specific lysis and concomitantly induce nonspecific lysis in an Fc-dependent way.
针对不同靶细胞的抗原特异性和抗原非特异性裂解，研究了单克隆抗T3抗体对细胞毒性T淋巴细胞（CTL）效应阶段的影响。抗T3抗体抑制了混合淋巴细胞培养（MLC）中产生的CTL的抗原特异性裂解，但同时增强了对第三方细胞（如细胞系Daudi、Raji和K562）的非特异性杀伤。这种非特异性细胞毒性由多种抗T3抗体诱导，而与细胞毒性效应细胞上表达的其他抗原反应的抗体则缺乏任何此类活性。只有当使用通过初次MLC、反复再刺激或克隆获得的活化T细胞时，抗T3抗体才会诱导非特异性细胞毒性。这些抗体对未刺激的外周T淋巴细胞或胸腺细胞没有影响。抗T3对抗原特异性裂解的抑制和非特异性裂解的诱导呈剂量依赖性，且两种效应都发生在抗T3的相同浓度范围内。抗T3的F(ab')2片段抑制特异性裂解，但不能诱导细胞毒性活性，这表明这种诱导是一个依赖Fc的过程。当测试不同的靶细胞时，只有Fc受体阳性细胞对这种非特异性细胞毒性敏感。因此，抗T3抗体对效应CTL有双重作用：它们抑制抗原特异性裂解，并以依赖Fc的方式同时诱导非特异性裂解。
