title: T-cell development and function are modulated by dual specificity phosphatase DUSP5.
abstract: Interleukin-2 (IL-2) is a pleiotropic cytokine that regulates lymphocyte proliferation and peripheral tolerance. IL-2 activates mitogen-activated protein kinase (MAPK), phosphatidylinositol 3-kinase, and signal transducer and activator of transcription (STAT) pathways and modulates expression of target genes. Systematic analysis of IL-2 target genes has revealed regulation of potential feedback inhibitors of IL-2 signaling, including several suppressor of cytokine signaling (SOCS) family members as well as MAPK pathway-regulating dual specificity phosphatases (DUSPs). Here we have evaluated the in vivo actions of DUSP5, an extracellular signal-regulated kinase 1/2 (ERK1/2)-specific phosphatase, by generating transgenic mice overexpressing DUSP5 within the lymphoid compartment. We show that transgenic DUSP5 expression results in a block in thymocyte development at the double positive stage. We also demonstrate that DUSP5-expressing mature T cells exhibit decreased IL-2-dependent proliferation and defective IL-2-mediated induction of genes. Finally, DUSP5 transgenic mice develop autoimmune symptoms, suggesting a role for the MAPK pathway in the regulation of tolerance. Thus, proper regulation of DUSP5 activity is critical for normal immune system development, IL-2 actions, and tolerance.
authors.affiliation: Laboratory of Molecular Immunology, NHLBI, NCI, National Institutes of Health, Bethesda, Maryland 20892, USA.
authors.forename: Panu E
authors.initials: PE
authors.lastname: Kovanen
authors.forename: Jérôme
authors.initials: J
authors.lastname: Bernard
authors.forename: Amin
authors.initials: A
authors.lastname: Al-Shami
authors.forename: Chengyu
authors.initials: C
authors.lastname: Liu
authors.forename: Julie
authors.initials: J
authors.lastname: Bollenbacher-Reilley
authors.forename: Lynn
authors.initials: L
authors.lastname: Young
authors.forename: Cynthia
authors.initials: C
authors.lastname: Pise-Masison
authors.forename: Rosanne
authors.initials: R
authors.lastname: Spolski
authors.forename: Warren J
authors.initials: WJ
authors.lastname: Leonard
mesh_terms: D000818:Animals; D054637:Dual-Specificity Phosphatases / Q000502:physiology*; D006801:Humans; D007108:Immune Tolerance; D007376:Interleukin-2 / Q000378:metabolism; D020935:MAP Kinase Signaling System; D051379:Mice; D008810:Mice, Inbred C57BL; D008822:Mice, Transgenic; D019950:Mitogen-Activated Protein Kinase 1 / Q000378:metabolism; D048052:Mitogen-Activated Protein Kinase 3 / Q000378:metabolism; D008954:Models, Biological; D019869:Phosphatidylinositol 3-Kinases / Q000378:metabolism; D013601:T-Lymphocytes / Q000166:cytology* / Q000378:metabolism; D013950:Thymus Gland / Q000166:cytology
chemical_list: D007376:Interleukin-2; D019869:Phosphatidylinositol 3-Kinases; D019950:Mitogen-Activated Protein Kinase 1; D048052:Mitogen-Activated Protein Kinase 3; C442320:DUSP5 protein, human; D054637:Dual-Specificity Phosphatases