Gilfillan S, Waltzinger C, Benoist C, Mathis D
Laboratoire de Génétique Moléculaire des Eucaryotes, du CNRS, U184 de l'INSERM, Strasbourg, France.
Int Immunol. 1994 Nov;6(11):1681-6. doi: 10.1093/intimm/6.11.1681.
Mice with a drastic mutation in the terminal deoxynucleotidyl transferase (TdT) gene have recently been engineered. Igs and TCRs in these mice are essentially devoid of N-region diversity. Here we report that TdT0 mice contain elevated numbers of CD3hi single-positive (SP) thymocytes because more thymocytes make the transition from the immature double-positive to the mature SP stage. This suggests that the repertoire of TCRs encoded in the germline may be enriched for specificities capable of interacting with MHC molecules and that the loss of some of this affinity is the price paid for TdT-generated diversity.
最近已构建出末端脱氧核苷酸转移酶（TdT）基因发生剧烈突变的小鼠。这些小鼠的免疫球蛋白（Igs）和T细胞受体（TCRs）基本上缺乏N区多样性。在此我们报告，TdT0小鼠含有数量增多的CD3高表达单阳性（SP）胸腺细胞，因为更多的胸腺细胞从未成熟双阳性阶段过渡到成熟SP阶段。这表明种系编码的TCR库可能富含能够与主要组织相容性复合体（MHC）分子相互作用的特异性，并且失去部分这种亲和力是为TdT产生的多样性所付出的代价。
