Altered major histocompatibility complex restriction in the NK1.1+Ly-6Chi autoreactive CD4+ T cell subset from class II-deficient mice.
We previously demonstrated selective enrichment of major histocompatibility complex (MHC) class II-specific autoreactive T cells in a subset of mouse CD4+ thymocytes. Here we show that a significant fraction of these autoreactive cells in the normal adult thymus expresses NK1.1 and high levels of Ly-6C and also exhibits flexibility in MHC restriction. In normal mice, this NK1.1+Ly-6Chi subfraction accounts for 10-50% of the CD4+ autoreactive subset and is enriched for MHC class II-restricted autoreactive cells as determined by mixed leukocyte reaction frequency analysis, similar to NK1.1-Ly-6C-CD4+ autoreactive cells. In contrast, in the thymus of class II-deficient littermate mice, NK1.1+Ly-6Chi cells account for most of the mature heat stable antigen (HSA)-CD4+ fraction and exhibit MHC-restricted non-class II autoreactivity. Thus, NK1.1+Ly-6ChiCD4+ T cells show flexibility in MHC class restriction, but their autoreactivity remains MHC dependent.
Institute for Cancer Research, Fox Chase Cancer Center, Philadelphia, Pennsylvania 19111.
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Kariv
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Hardy
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Hayakawa
D000375:Aging / Q000276:immunology; D000818:Animals; D000911:Antibodies, Monoclonal; D000950:Antigens, Ly / Q000276:immunology*; D015496:CD4-Positive T-Lymphocytes / Q000276:immunology*; D005434:Flow Cytometry; D000949:Histocompatibility Antigens Class II / Q000235:genetics / Q000502:physiology*; D007694:Killer Cells, Natural / Q000276:immunology*; D008285:Major Histocompatibility Complex; D051379:Mice; D008807:Mice, Inbred BALB C; D008810:Mice, Inbred C57BL; D008815:Mice, Inbred Strains; D013045:Species Specificity; D016176:T-Lymphocyte Subsets / Q000276:immunology; D013950:Thymus Gland / Q000254:growth & development / Q000276:immunology
D000911:Antibodies, Monoclonal; D000950:Antigens, Ly; D000949:Histocompatibility Antigens Class II