Homeostatic maintenance of T cells and natural killer cells
Homeostasis in the immune system encompasses the mechanisms governing maintenance of a functional and diverse pool of lymphocytes, thus guaranteeing immunity to pathogens while remaining self-tolerant. Antigen-naive T cells rely on survival signals through contact with self-peptide-loaded major histocompatibility complex (MHC) molecules plus interleukin (IL)-7. Conversely, antigen-experienced (memory) T cells are typically MHC-independent and they survive and undergo periodic homeostatic proliferation through contact with both IL-7 and IL-15. Also, non-conventional gammadelta T cells rely on a mix of IL-7 and IL-15 for their homeostasis, whereas natural killer cells are mainly dependent on contact with IL-15. Homeostasis of CD4(+) T regulatory cells is different in being chiefly regulated by contact with IL-2. Notably, increased levels of these cytokines cause expansion of responsive lymphocytes, such as found in lymphopenic hosts or following cytokine injection, whereas reduced cytokine levels cause a decline in cell numbers.
|Authors||Boyman, O.; Krieg, C.; Homann, D.; Sprent, J.:|
|Publisher Name||CELLULAR AND MOLECULAR LIFE SCIENCES|
|URL link to publisher's version||http://www.ncbi.nlm.nih.gov/pubmed/22460580|
|OpenAccess link to author's accepted manuscript version||https://publications.gimr.garvan.org.au/open-access/11392|