Min Booki, McHugh Rebecca, Sempowski Gregory D, Mackall Crystal, Foucras Gilles, Paul William E
Laboratory of Immunology, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, MD 20892, USA.
Immunity. 2003 Jan;18(1):131-40. doi: 10.1016/s1074-7613(02)00508-3.
T cells expand without intentional antigen stimulation when transferred into adult lymphopenic environments. In this study, we show that the physiologic lymphopenic environment existing in neonatal mice also supports CD4 T cell proliferation. Strikingly, naive CD4 T cells that proliferate within neonates acquire the phenotypic and functional characteristics of memory cells. Such proliferation is inhibited by the presence of both memory and naive CD4 T cells, is enhanced by 3-day thymectomy, is independent of IL-7, and requires a class II MHC-TCR interaction and a CD28-mediated signal. CD44(bright) CD4 T cells in neonates have a wide repertoire as judged by the distribution of Vbeta expression. Thus, lymphopenia-induced T cell proliferation is a physiologic process that occurs during the early postnatal period.
当转移到成年淋巴细胞减少的环境中时，T细胞在没有故意抗原刺激的情况下会发生扩增。在本研究中，我们表明新生小鼠中存在的生理性淋巴细胞减少环境也支持CD4 T细胞增殖。令人惊讶的是，在新生小鼠体内增殖的初始CD4 T细胞获得了记忆细胞的表型和功能特征。这种增殖受到记忆性和初始CD4 T细胞的抑制，通过3天胸腺切除术增强，不依赖于IL-7，并且需要II类MHC-TCR相互作用和CD28介导的信号。根据Vβ表达的分布判断，新生小鼠中的CD44(明亮) CD4 T细胞具有广泛的库。因此，淋巴细胞减少诱导的T细胞增殖是出生后早期发生的一个生理过程。
