Quiròs Roldan E, Sottini A, Imberti L, Mattioli S, Albertini A, Primi D
Dept. of Chemistry, School of Medicine, University of Brescia, Italy.
Res Immunol. 1994 Sep;145(7):517-31. doi: 10.1016/s0923-2494(94)80070-7.
A major characteristic of superantigens is their ability to stimulate T cells based predominantly on the type of variable segment of the T-cell receptor (TCR) V beta chain. Recently, however, reports from several laboratories have also implied a role for non-V beta elements in superantigen binding. The goal of the present study was to determine whether TCR V beta-D beta-J beta joining sequences may influence the interaction of superantigens with their target cells. To ascertain how the actual TCR repertoire of superantigen-triggered cells deviates from the theoretical one, we generated a large panel of joining region sequences from TCR carrying the TCR V beta 12 and TCR V beta 5,1 regions. The 245 sequences analysed represent transcripts of T cells from the same donor triggered either with an anti-CD3 monoclonal antibody or with the Staphylococcus aureus enterotoxins. Comparison of the joining sequences of these different groups demonstrates a skewed J beta usage in the sequences derived from superantigen-triggered cells and also provides evidence that ascribes to the putative CDR3 region of V beta segments a role in superantigen recognition. Finally, the data presented give some hints of the regions of the putative CDR3 loop that may play a major role in this function.
超抗原的一个主要特征是它们主要基于T细胞受体（TCR）Vβ链可变区的类型来刺激T细胞的能力。然而，最近几个实验室的报告也暗示了非Vβ元件在超抗原结合中的作用。本研究的目的是确定TCR Vβ-Dβ-Jβ连接序列是否会影响超抗原与其靶细胞的相互作用。为了确定超抗原触发细胞的实际TCR库与理论库有何偏差，我们从携带TCR Vβ12和TCR Vβ5、1区的TCR中生成了大量连接区序列。分析的245个序列代表来自同一供体的T细胞转录本，这些T细胞用抗CD3单克隆抗体或金黄色葡萄球菌肠毒素触发。对这些不同组的连接序列进行比较，结果显示超抗原触发细胞衍生的序列中Jβ使用存在偏差，同时也提供了证据，表明Vβ片段的推定互补决定区3（CDR3）在超抗原识别中发挥作用。最后，所呈现的数据给出了可能在该功能中起主要作用的推定CDR3环区域的一些线索。
