期刊名称：Proceedings of the National Academy of Sciences
印刷版ISSN：0027-8424
电子版ISSN：1091-6490
出版年度：2002
卷号：99
期号：2
页码：878-883
DOI：10.1073/pnas.022326699
语种：English
出版社：The National Academy of Sciences of the United States of America
摘要：Susceptibility of activated T cells to apoptosis must be tightly regulated to ensure sufficient T cell progeny for an effective response, while allowing a rapid depletion of them at the end of the immune response. We show here that a previously isolated, NF-{kappa}B/rel target gene IEX-1 (Immediate Early response gene X-1) is highly expressed in T cells at early stages of activation, but declines with a prolonged period of activation time, coincident with an increased susceptibility of T cells to apoptosis during the late phases of an immune response. Transgenic expression of IEX-1 specifically in lymphocytes impaired apoptosis in activated T cells, extended a duration of an effector-phase of a specific immune response, and increased the accumulation of effector/memory-like T cells and the susceptibility to a lupus-like autoimmune disease. Our study demonstrated an antiapoptotic effect of IEX-1 on T cell apoptosis triggered by ligation of Fas and T cell receptor (TCR)/CD3 complex. The ability of extending life expectancy of T effectors, in line with a decrease in its expression following prolonged T cell activation, suggests a key role for IEX-1 in regulating T cell homeostasis during immune responses.
