title: CD4+ T cells from IRF-1-deficient mice exhibit altered patterns of cytokine expression and cell subset homeostasis.
abstract: Interferon regulatory factor-1 (IRF-1) is a member of a family of transcription factors that regulate an array of genes involved in cell growth, differentiation, and death. Analysis of cytokine expression by stimulated CD4+ cells from IRF-1(-/-) and IRF-1(+/+) mice revealed that IRF-1 deficiency resulted in an elevated production of Th2-related cytokines and a compensatory decrease in the expression of naive cell- and Th1-related cytokines. The altered cytokine profiles of IRF-1(-/-) cells could be explained, in part, by a shift in the representation of subsets of CD4+ cells; IRF-1(-/-) mice exhibited a decreased percentage of naive cells (a major source of IL-2) but increased numbers of memory or effector cells (the source of Th2-related cytokines). We analyzed purified, phenotypically matched memory/effector cells from IRF-1(-/-) and IRF-1(+/+) mice and found that the increased Th2:Th1 cytokine ratio was still evident in the IRF-1(-/-) group, thus suggesting that IRF-1 is involved in the polarization of the cytokine repertoire in CD4+ cells. Our data indicate that IRF-1 plays an important role in the maintenance of CD4+ cell subset homeostasis and in the expression of cytokines by naive and memory/effector cells.
authors.affiliation: Department of Immunology, The Scripps Research Institute, La Jolla, CA 92037, USA.
authors.forename: D L
authors.initials: DL
authors.lastname: McElligott
authors.forename: J A
authors.initials: JA
authors.lastname: Phillips
authors.forename: C A
authors.initials: CA
authors.lastname: Stillman
authors.forename: R J
authors.initials: RJ
authors.lastname: Koch
authors.forename: D E
authors.initials: DE
authors.lastname: Mosier
authors.forename: M V
authors.initials: MV
authors.lastname: Hobbs
mesh_terms: D000818:Animals; D015496:CD4-Positive T-Lymphocytes / Q000276:immunology* / Q000378:metabolism; D016207:Cytokines / Q000096:biosynthesis / Q000276:immunology*; D004268:DNA-Binding Proteins / Q000235:genetics / Q000276:immunology*; D005786:Gene Expression Regulation; D050856:Interferon Regulatory Factor-1; D007371:Interferon-gamma / Q000235:genetics / Q000276:immunology; D051379:Mice; D008807:Mice, Inbred BALB C; D008817:Mice, Mutant Strains; D010750:Phosphoproteins / Q000235:genetics / Q000276:immunology*; D016176:T-Lymphocyte Subsets / Q000276:immunology* / Q000378:metabolism; D014157:Transcription Factors / Q000235:genetics / Q000276:immunology
chemical_list: D016207:Cytokines; D004268:DNA-Binding Proteins; D050856:Interferon Regulatory Factor-1; C494258:Irf1 protein, mouse; D010750:Phosphoproteins; D014157:Transcription Factors; D007371:Interferon-gamma