title: Expression and function of major histocompatibiliby complex antigens in the developing thymus: studies on normal and nude mice.
abstract: Direct access of lymphoid precursors to the thymic environment appears to be an essential step in the differentiation of normal T cell populations and it is possible that intimate cellular interactions between T cells and the thymic stroma are involved in selective processes leading to self-tolerance and major histocompatibility complex (MHC) restriction. As an approach to investigating the intrathymic environment, MHC antigen expression during normal thymic development and lymphopoiesis, and in the embryonic thymus of T cell-deficient nude mice, has been examined. Evidence has been obtained to show that MHC antigens controlled by both the K and I regions are expressed from an early stage on epithelial cells in normal thymus development but that the thymic rudiment in nude mice shows a selective absence of I regions antigens. The implications of these findings for T cell development and the derivation and constitution of the intrathymic environment are considered.
mesh_terms: D000818:Animals; D004848:Epithelium / Q000276:immunology; D006183:H-2 Antigens; D006649:Histocompatibility Antigens; D000949:Histocompatibility Antigens Class II; D008285:Major Histocompatibility Complex; D051379:Mice; D008810:Mice, Inbred C57BL; D008808:Mice, Inbred CBA; D008819:Mice, Nude; D013601:T-Lymphocytes / Q000276:immunology; D013950:Thymus Gland / Q000196:embryology / Q000276:immunology*
chemical_list: D006183:H-2 Antigens; D006649:Histocompatibility Antigens; D000949:Histocompatibility Antigens Class II