Antiviral CD4+ memory T cells are IL-15 dependent.

ABSTRACT: Survival and intermittent proliferation of memory CD4(+) and CD8(+) T cells appear to be controlled by different homeostatic mechanisms. In particular, contact with interleukin (IL)-15 has a decisive influence on memory CD8(+) cells, but not memory CD4(+) cells. Past studies of memory CD4(+) cells have relied heavily on the use of naturally occurring memory phenotype (MP) cells as a surrogate for antigen (Ag)-specific memory cells. However, we show here that MP CD4(+) cells contain a prominent subset of rapidly proliferating major histocompatibility complex (MHC) II-dependent cells. In contrast, Ag-specific memory CD4 cells have a slow turnover rate and are MHC II independent. In irradiated hosts, these latter cells ignore IL-15 and expand in response to the elevated levels of IL-7 in the

SUBMITTER: Purton JF 

PROVIDER: S-EPMC2118539 | biostudies-literature | 2007 Apr

REPOSITORIES: biostudies-literature