title: A role for Stat5 in CD8+ T cell homeostasis.
abstract: Cytokine signals are known to contribute to CD8+ memory T cell homeostasis, but an exact understanding of the mechanism(s) has remained elusive. We have now investigated the role of Stat5 proteins in this process. Whereas Stat5a and Stat5b KO mice have decreased numbers of CD8+ T cells, Stat5-transgenic mice have an increased number of these cells. Stat5b-transgenic mice exhibit increased Ag-induced cell death of CD4+ T cells and augmented proliferation and Bcl-2 expression in CD8+ T cells, providing a basis for this finding. Moreover, CD8+ memory T cells are substantially affected by Stat5 levels. These findings identify Stat5 proteins as critical signaling mediators used by cytokines to regulate CD8+ T cell homeostasis.
authors.affiliation: Laboratory of Molecular Immunology, National Heart, Lung, and Blood Institute, National Institutes of Health, Bethesda, MD 20892, USA.
authors.forename: John
authors.initials: J
authors.lastname: Kelly
authors.forename: Rosanne
authors.initials: R
authors.lastname: Spolski
authors.forename: Kazunori
authors.initials: K
authors.lastname: Imada
authors.forename: Julie
authors.initials: J
authors.lastname: Bollenbacher
authors.forename: Stephen
authors.initials: S
authors.lastname: Lee
authors.forename: Warren J
authors.initials: WJ
authors.lastname: Leonard
mesh_terms: D000818:Animals; D016516:CD4-CD8 Ratio; D018414:CD8-Positive T-Lymphocytes / Q000166:cytology* / Q000276:immunology* / Q000378:metabolism; D002455:Cell Division / Q000235:genetics / Q000276:immunology; D002470:Cell Survival / Q000235:genetics / Q000276:immunology; D002478:Cells, Cultured; D018946:Chemokine CCL5 / Q000096:biosynthesis; D003433:Crosses, Genetic; D004268:DNA-Binding Proteins / Q000172:deficiency / Q000235:genetics / Q000378:metabolism / Q000502:physiology*; D005260:Female; D006706:Homeostasis / Q000235:genetics / Q000276:immunology*; D007371:Interferon-gamma / Q000096:biosynthesis; D053631:Interleukin Receptor Common gamma Subunit; D008213:Lymphocyte Activation / Q000235:genetics; D008297:Male; D051379:Mice; D008807:Mice, Inbred BALB C; D008810:Mice, Inbred C57BL; D018345:Mice, Knockout; D008822:Mice, Transgenic; D008894:Milk Proteins; D020395:Receptors, Interleukin-7 / Q000172:deficiency / Q000235:genetics; D050799:STAT5 Transcription Factor; D015398:Signal Transduction / Q000235:genetics / Q000276:immunology*; D013154:Spleen / Q000166:cytology / Q000276:immunology / Q000378:metabolism; D015534:Trans-Activators / Q000172:deficiency / Q000235:genetics / Q000378:metabolism / Q000502:physiology*
chemical_list: D018946:Chemokine CCL5; D004268:DNA-Binding Proteins; C507942:Il2rg protein, mouse; D053631:Interleukin Receptor Common gamma Subunit; D008894:Milk Proteins; D020395:Receptors, Interleukin-7; D050799:STAT5 Transcription Factor; C494093:Stat5a protein, mouse; C494096:Stat5b protein, mouse; D015534:Trans-Activators; D007371:Interferon-gamma