Hao Yi, Legrand Nicolas, Freitas Antonio A
Unité Biologie des Populations Lymphocytaires, Unité de Recherche Associé Centre National de la Recherche Scientifique 1961 Institut Pasteur, 75724 Paris Cedex 15, France.
J Exp Med. 2006 Jul 10;203(7):1643-9. doi: 10.1084/jem.20052174. Epub 2006 Jun 12.
Positive selection in the thymus and peripheral T cell survival depend on T cell receptor (TCR)-major histocompatibility complex (MHC) interactions, but it is not yet clear if both events follow exactly the same rules. We studied peripheral T cell survival and clone sizes in conditions of progressive reduction of restricting MHC-bearing cells or progressive ablation of different MHC molecules. Different CD8(+) T cell clones/polyclonal populations showed different survival and/or lymphopenia-driven proliferation requirements. We could correlate clone sizes to the capacity of each TCR to interact with different types of MHC complexes. Thus, although repertoire selection in the thymus is mainly conditioned by the affinity of TCR-MHC interactions, peripheral selection is determined by TCR cross-reactivity to environmental ligands.
胸腺中的阳性选择和外周T细胞存活依赖于T细胞受体（TCR）-主要组织相容性复合体（MHC）的相互作用，但目前尚不清楚这两个过程是否遵循完全相同的规则。我们研究了在携带限制性MHC的细胞逐渐减少或不同MHC分子逐渐消融的条件下外周T细胞的存活和克隆大小。不同的CD8(+) T细胞克隆/多克隆群体表现出不同的存活和/或淋巴细胞减少驱动的增殖需求。我们可以将克隆大小与每个TCR与不同类型MHC复合体相互作用的能力相关联。因此，尽管胸腺中的库选择主要由TCR-MHC相互作用的亲和力决定，但外周选择则由TCR对环境配体的交叉反应性决定。
