title: Requirement for TNF-alpha and IL-1 alpha in fetal thymocyte commitment and differentiation.
abstract: CD25 expression occurs early in thymocyte differentiation. The mechanism of induction of CD25 before T cell receptor rearrangement and the importance of this mechanism for T cell development are unknown. In a thymus reconstitution assay, tumor necrosis factor alpha (TNF-alpha) and interleukin-1 alpha (IL-1 alpha), two cytokines produced within the thymic microenvironment, induced CD25 expression on early immature thymocytes. Either TNF-alpha or IL-1 alpha was necessary for further thymocyte maturation and CD4+CD8+ differentiation. In irradiated mice reconstituted with CD117+CD25+ thymocytes, commitment to the T cell lineage was marked by the loss of precursor multipotency.
authors.affiliation: Laboratory of Immunology, National Institute of Allergy and Infectious Diseases, Bethesda, MD 20892, USA.
authors.forename: J C
authors.initials: JC
authors.lastname: Zúñiga-Pflücker
authors.forename: D
authors.initials: D
authors.lastname: Jiang
authors.forename: M J
authors.initials: MJ
authors.lastname: Lenardo
mesh_terms: D000818:Animals; D002454:Cell Differentiation; D002478:Cells, Cultured; D006412:Hematopoietic Stem Cells / Q000166:cytology* / Q000276:immunology; D007375:Interleukin-1 / Q000494:pharmacology / Q000502:physiology*; D015851:Interleukin-7 / Q000494:pharmacology; D051379:Mice; D008807:Mice, Inbred BALB C; D008810:Mice, Inbred C57BL; D016513:Mice, SCID; D009924:Organ Culture Techniques; D011518:Proto-Oncogene Proteins / Q000096:biosynthesis; D019009:Proto-Oncogene Proteins c-kit; D020794:Receptor Protein-Tyrosine Kinases / Q000096:biosynthesis; D016184:Receptors, Colony-Stimulating Factor / Q000096:biosynthesis; D015375:Receptors, Interleukin-2 / Q000096:biosynthesis*; D017154:Stromal Cells / Q000502:physiology; D016176:T-Lymphocyte Subsets / Q000166:cytology / Q000276:immunology; D013601:T-Lymphocytes / Q000166:cytology* / Q000276:immunology; D013950:Thymus Gland / Q000166:cytology / Q000196:embryology* / Q000276:immunology; D014409:Tumor Necrosis Factor-alpha / Q000494:pharmacology / Q000502:physiology*
chemical_list: D007375:Interleukin-1; D015851:Interleukin-7; D011518:Proto-Oncogene Proteins; D016184:Receptors, Colony-Stimulating Factor; D015375:Receptors, Interleukin-2; D014409:Tumor Necrosis Factor-alpha; D019009:Proto-Oncogene Proteins c-kit; D020794:Receptor Protein-Tyrosine Kinases