title: IL-21 induces apoptosis of antigen-specific CD8+ T lymphocytes.
abstract: IL-21, a member of the common gamma-chain family of cytokines, has pleiotropic effects on T, B, and NK cells. We found that IL-21 and the prototype common gamma-chain cytokine IL-2 can stimulate proliferation and cytokine secretion by Ag-specific rhesus monkey CD8+ T cells. However, unique among the members of this family of cytokines, we found that IL-21 drives these cells to apoptosis by down-regulation of Bcl-2. These findings suggest that IL-21 may play an important role in the contraction of CD8+ T cell responses.
authors.affiliation: Division of Viral Pathogenesis, Department of Medicine, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, MA 02115.
authors.forename: Brianne R
authors.initials: BR
authors.lastname: Barker
authors.forename: Jenny G
authors.initials: JG
authors.lastname: Parvani
authors.forename: Debra
authors.initials: D
authors.lastname: Meyer
authors.forename: Adam S
authors.initials: AS
authors.lastname: Hey
authors.forename: Kresten
authors.initials: K
authors.lastname: Skak
authors.forename: Norman L
authors.initials: NL
authors.lastname: Letvin
mesh_terms: D000818:Animals; D017209:Apoptosis / Q000276:immunology*; D018414:CD8-Positive T-Lymphocytes / Q000166:cytology* / Q000276:immunology* / Q000378:metabolism; D016923:Cell Death / Q000276:immunology; D002478:Cells, Cultured; D018984:Epitopes, T-Lymphocyte / Q000276:immunology*; D006801:Humans; D007156:Immunologic Memory; D007371:Interferon-gamma / Q000378:metabolism; D053738:Interleukin-21 Receptor alpha Subunit / Q000096:biosynthesis; D007378:Interleukins / Q000502:physiology*; D008213:Lymphocyte Activation / Q000276:immunology; D008253:Macaca mulatta; D010766:Phosphorylation; D019253:Proto-Oncogene Proteins c-bcl-2 / Q000037:antagonists & inhibitors / Q000096:biosynthesis; D011994:Recombinant Proteins / Q000494:pharmacology; D050796:STAT3 Transcription Factor / Q000378:metabolism; D050799:STAT5 Transcription Factor / Q000378:metabolism; D000098546:Interleukin-21