Memory CD8 T-cell compartment grows in size with immunological experience

Article

关键词: VIRAL-INFECTIONS;    IMMUNITY;    HOMEOSTASIS;    VACCINATION;    POPULATION;    PROTECTION;    PHENOTYPE;    ATTRITION;    SURVIVAL;    SUBSETS;   

DOI  :  10.1038/nature07486

来源: SCIE

【 摘 要 】

Memory CD8 T cells, generated by natural pathogen exposure or intentional vaccination, protect the host against specific viral infections(1). It has long been proposed that the number of memory CD8 T cells in the host is inflexible, and that individual cells are constantly competing for limited space(2,3). Consequently, vaccines that introduce over- abundant quantities of memory CD8 T cells specific for an agent of interest could have catastrophic consequences for the host by displacing memory CD8 T cells specific for all previous infections(4-6). To test this paradigm, we developed a vaccination regimen in mice that introduced as many new long- lived memory CD8 T cells specific for a single vaccine antigen as there were memory CD8 T cells in the host before vaccination. Here we show that, in contrast to expectations, the size of the memory CD8 T- cell compartment doubled to accommodate these new cells, a change due solely to the addition of effector memory CD8 T cells. This increase did not affect the number of CD4 T cells, B cells or naive CD8 T cells, and pre- existing memory CD8 T cells specific for a previously encountered infection were largely preserved. Thus, the number of effector memory CD8 T cells in the mammalian host adapts according to immunological experience. Developing vaccines that abundantly introduce new memory CD8 T cells should not necessarily ablate pre- existing immunity to other infections.

【 授权许可】

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