title: Critical requirement for the Wiskott-Aldrich syndrome protein in Th2 effector function.
abstract: Patients with Wiskott-Aldrich syndrome (WAS) have numerous immune cell deficiencies, but it remains unclear how abnormalities in individual cell types contribute to the pathologies of WAS. In T cells, the WAS protein (WASp) regulates actin polymerization and transcription, and plays a role in the dynamics of the immunologic synapse. To examine how these events influence CD4 function, we isolated the WASp deficiency to CD4(+) T cells by adoptive transfer into wild-type mice to study T-cell priming and effector function. WAS(-/-) CD4(+) T cells mediated protective T-helper 1 (Th1) responses to Leishmania major in vivo, but were unable to support Th2 immunity to Nippostrongylus brasiliensis or L major. Mechanistically, WASp was not required for Th2 programming but was required for Th2 effector function. WAS(-/-) CD4(+) T cells up-regulated IL-4 and GATA3 mRNA and secreted IL-4 protein during Th2 differentiation. In contrast, cytokine transcription was uncoupled from protein production in WAS(-/-) Th2-primed effectors. WAS(-/-) Th2s failed to produce IL-4 protein on restimulation despite elevated IL-4/GATA3 mRNA. Moreover, dominant-negative WASp expression in WT effector T cells blocked IL-4 production, but had no effect on IFNgamma. Thus WASp plays a selective, posttranscriptional role in Th2 effector function.
authors.affiliation: David H. Smith Center for Vaccine Biology and Immunology, Aab Institute of Biomedical Sciences, Department of Microbiology and Immunology, University of Rochester, NY, USA.
authors.forename: Vanessa
authors.initials: V
authors.lastname: Morales-Tirado
authors.forename: Dorothy K
authors.initials: DK
authors.lastname: Sojka
authors.forename: Shoshana D
authors.initials: SD
authors.lastname: Katzman
authors.forename: Christopher A
authors.initials: CA
authors.lastname: Lazarski
authors.forename: Fred D
authors.initials: FD
authors.lastname: Finkelman
authors.forename: Joseph F
authors.initials: JF
authors.lastname: Urban
authors.forename: Deborah J
authors.initials: DJ
authors.lastname: Fowell
mesh_terms: D000818:Animals; D050990:GATA3 Transcription Factor / Q000096:biosynthesis / Q000235:genetics / Q000276:immunology; D006801:Humans; D007371:Interferon-gamma / Q000235:genetics / Q000276:immunology / Q000378:metabolism; D015847:Interleukin-4 / Q000096:biosynthesis / Q000235:genetics / Q000276:immunology; D018320:Leishmania major / Q000276:immunology; D016773:Leishmaniasis, Cutaneous / Q000235:genetics / Q000276:immunology / Q000378:metabolism; D051379:Mice; D008807:Mice, Inbred BALB C; D018345:Mice, Knockout; D009559:Nippostrongylus / Q000276:immunology; D012333:RNA, Messenger / Q000096:biosynthesis / Q000235:genetics / Q000276:immunology; D017206:Strongylida Infections / Q000235:genetics / Q000276:immunology / Q000378:metabolism; D018417:Th1 Cells / Q000276:immunology; D018418:Th2 Cells / Q000276:immunology* / Q000378:metabolism; D014158:Transcription, Genetic / Q000235:genetics / Q000276:immunology; D015854:Up-Regulation / Q000235:genetics / Q000276:immunology; D014923:Wiskott-Aldrich Syndrome / Q000235:genetics / Q000276:immunology / Q000378:metabolism; D051316:Wiskott-Aldrich Syndrome Protein / Q000235:genetics / Q000276:immunology* / Q000378:metabolism
chemical_list: D050990:GATA3 Transcription Factor; C494748:Gata3 protein, mouse; D012333:RNA, Messenger; C495768:Was protein, mouse; D051316:Wiskott-Aldrich Syndrome Protein; D015847:Interleukin-4; D007371:Interferon-gamma