Fraser J D, Goldsmith M A, Weiss A
Department of Medicine, University of California, San Francisco.
Proc Natl Acad Sci U S A. 1989 Sep;86(18):7133-7. doi: 10.1073/pnas.86.18.7133.
We have identified two cell surface glycoproteins of 34 and 38 kDa (gp34 and gp38) that associate with the T-cell antigen receptor (TCR). The coimmunoprecipitation of these proteins with the TCR is increased by treatment with monoclonal antibodies (mAbs) directed against the TCR prior to cell solubilization and immunoprecipitation. Treatment of T cells with mAbs directed against other cell surface molecules, CD2 or HLA, does not induce the association of these proteins with the TCR. The coimmunoprecipitation of gp34 and gp38 with the TCR requires solubilization in the presence of an alkylating agent, suggesting that subunit alkylation stabilizes the interaction. J.CaM1 and J.CaM2 are signal-transduction mutant cell lines derived from Jurkat. These cell lines fail to activate the inositol phospholipid second messenger pathway in response to anti-TCR mAbs. Treatment with mAb C305 (anti-TCR) induces the association of gp34 and gp38 with the TCR in J.CaM2 cells but not in J.CaM1. J.CaM1 modulates the TCR normally in response to anti-TCR antibody treatment. This observation suggests that gp34 and gp38 are involved in the signal-transduction pathway of the TCR complex rather than receptor internalization. Furthermore, since these proteins do associate with the TCR of J.CaM2, the induced association with the TCR is not a consequence of signal transduction.
我们已经鉴定出两种分别为34 kDa和38 kDa的细胞表面糖蛋白（gp34和gp38），它们与T细胞抗原受体（TCR）相关联。在细胞溶解和免疫沉淀之前，用针对TCR的单克隆抗体（mAb）处理会增加这些蛋白与TCR的共免疫沉淀。用针对其他细胞表面分子（CD2或HLA）的mAb处理T细胞，不会诱导这些蛋白与TCR的关联。gp34和gp38与TCR的共免疫沉淀需要在烷基化剂存在的情况下进行溶解，这表明亚基烷基化稳定了这种相互作用。J.CaM1和J.CaM2是源自Jurkat的信号转导突变细胞系。这些细胞系在响应抗TCR mAb时无法激活肌醇磷脂第二信使途径。用mAb C305（抗TCR）处理会诱导gp34和gp38在J.CaM2细胞中与TCR关联，但在J.CaM1细胞中则不会。J.CaM1在响应抗TCR抗体处理时能正常调节TCR。这一观察结果表明，gp34和gp38参与了TCR复合物的信号转导途径，而非受体内化。此外，由于这些蛋白确实与J.CaM2的TCR相关联，所以与TCR的诱导关联不是信号转导的结果。
