Tanchot C, Fernandes H V, Rocha B
Institute National de la Santé et de la Recherche Médicale U345, Institut Necker, Paris, France.
Philos Trans R Soc Lond B Biol Sci. 2000 Mar 29;355(1395):323-8. doi: 10.1098/rstb.2000.0569.
To deal with exogenous pathogens the peripheral T-cell compartment requires diverse repertoires (as those of naive cells) and efficient responses, the latter dependent on the persistence of memory cells. In the present work we show that (i) naive and memory cells differ in the type of interactions required for survival and division; (ii) they are segregated into independent ecological niches; (iii) that the size of each niche is controlled by independent homeostatic mechanisms; and (iv) that naive T cells do not have intrinsic life spans, surviving in the absence of thymus output but being continuously substituted by thymus export. The independent homeostatic regulation of the naive and memory T-cell pools guarantees the maintenance of versatile and efficient repertoires throughout life as well as the persistence of the naive T-cell pool after the thymus atrophies at puberty.
为应对外源性病原体，外周T细胞区室需要多样化的库（如初始细胞的库）以及高效的反应，后者依赖于记忆细胞的持续存在。在本研究中，我们表明：（i）初始细胞和记忆细胞在生存和分裂所需的相互作用类型上存在差异；（ii）它们被分隔到独立的生态位中；（iii）每个生态位的大小由独立的稳态机制控制；以及（iv）初始T细胞没有内在寿命，在没有胸腺输出的情况下存活，但会被胸腺输出持续替代。初始T细胞库和记忆T细胞库的独立稳态调节确保了一生中多功能且高效的库的维持，以及青春期胸腺萎缩后初始T细胞库的持续存在。
