Hodes R J, Sharrow S O, Solomon A
Experimental Immunology Branch, National Cancer Institute, Bethesda, MD 20892.
Science. 1989 Nov 24;246(4933):1041-4. doi: 10.1126/science.2587987.
The mature T cell receptor (TCR) repertoire is the result of selection events during T cell development. Previous assessment of TCR beta-chain selection with serologic and molecular probes demonstrated both positive and negative selection. Although this work suggested a critical role for the thymus, no direct assessment has been made of the requirement for a thymus in TCR V beta selection. A comparison of TCR V beta expression in four different congenic pairs of normal and nu/nu (athymic) mice indicated that the normal V beta deletions associated with tolerance to self minor lymphocyte stimulating (Mlsc) antigens or to self major histocompatibility complex (MHC)-encoded E alpha E beta products did not occur in most athymic mice. Thus, the thymus has a critical role in mediating self tolerance by negative selection.
成熟的T细胞受体（TCR）库是T细胞发育过程中选择事件的结果。先前使用血清学和分子探针评估TCRβ链选择，结果显示既有阳性选择也有阴性选择。尽管这项工作表明胸腺起着关键作用，但尚未对胸腺在TCR Vβ选择中的必要性进行直接评估。对四对不同的正常同基因和nu/nu（无胸腺）小鼠的TCR Vβ表达进行比较，结果表明，与对自身次要淋巴细胞刺激（Mlsc）抗原或自身主要组织相容性复合体（MHC）编码的EαEβ产物产生耐受性相关的正常Vβ缺失，在大多数无胸腺小鼠中并未出现。因此，胸腺在通过阴性选择介导自身耐受性方面起着关键作用。
