Li Z G, Kemp O, Longhurst T, Manolios N
Sutton Rheumatism Research Laboratory, Department of Rheumatology, Royal North Shore Hospital, Sydney, Australia.
Scand J Immunol. 1996 Feb;43(2):140-5. doi: 10.1046/j.1365-3083.1996.d01-21.x.
The clonotypic T-cell antigen receptor (TCR)-beta chain contains two extracellular intrachain disulfide bonds. It belongs to the immunoglobulin gene superfamily and is subdivided into variable (V), joining (J), diversity (D) and constant (C) region. Monoclonal antibody (MoAb) KJ25 is believed to recognize an epitope in the V-domain of TCR-beta (V beta 3) chain, but its epitope requirements are unknown. In this study of TCR-alpha beta chain interactions using chimeric recombinant TCR-beta chains, the authors found that partial substitution of the C beta-domain with that of interleukin-2 receptor alpha chain (Tac) sequences led to the loss of TCR-V beta 3 epitope recognition by KJ25. These results suggest that epitope recognition of the TCR-V beta 3 by KJ25 MoAb is dependent not only on the V-domain, but also on the close contact with the extracellular C-domain which influences the conformation and epitope recognition of the V beta 3-region. This may not be unique to V beta 3 and may be a general feature of TCR-beta protein folding.
克隆型T细胞抗原受体（TCR）β链含有两个细胞外链内二硫键。它属于免疫球蛋白基因超家族，可细分为可变（V）区、连接（J）区、多样性（D）区和恒定（C）区。单克隆抗体（MoAb）KJ25被认为可识别TCR-β（Vβ3）链V结构域中的一个表位，但其表位要求尚不清楚。在这项使用嵌合重组TCR-β链对TCR-αβ链相互作用的研究中，作者发现用白细胞介素-2受体α链（Tac）序列的Cβ结构域部分替代，会导致KJ25丧失对TCR-Vβ3表位的识别。这些结果表明，KJ25单克隆抗体对TCR-Vβ3的表位识别不仅取决于V结构域，还取决于与细胞外C结构域的紧密接触，而这种接触会影响Vβ3区域的构象和表位识别。这可能并非Vβ3所特有，可能是TCR-β蛋白折叠的一个普遍特征。
