Homeostasis of memory T cells

Immunol Rev. 2006 Jun;211:154-63. doi: 10.1111/j.0105-2896.2006.00401.x.


The pool of memory T cells is regulated by homeostatic mechanisms to persist for prolonged periods at a relatively steady overall size. Recent work has shown that two members of the common gamma chain (gammac) family of cytokines, interleukin-7 (IL-7) and IL-15, govern homeostasis of memory T cells. These two cytokines work in conjunction to support memory T-cell survival and intermittent background proliferation. Normal animals contain significant numbers of spontaneously arising memory-phenotype (MP) cells, though whether these cells are representative of true antigen-specific memory T cells is unclear. Nevertheless, it appears that the two types of memory cells do not display identical homeostatic requirements. For antigen-specific memory CD8+ T cells, IL-7 is primarily important for survival while IL-15 is crucial for their background proliferation. For memory CD4+ T cells, IL-7 has an important role, whereas the influence of IL-15 is still unclear.

Publication types

  • Research Support, N.I.H., Extramural
  • Research Support, Non-U.S. Gov't
  • Review

MeSH terms

  • Animals
  • CD8-Positive T-Lymphocytes / immunology
  • Homeostasis / immunology
  • Humans
  • Immunologic Memory / immunology*
  • Interferons / immunology
  • Interleukin-15 / immunology
  • Interleukin-7 / immunology
  • Mice
  • Receptors, Interleukin-2 / immunology
  • T-Lymphocytes / immunology*


  • Interleukin-15
  • Interleukin-7
  • Receptors, Interleukin-2
  • Interferons