title: Mature CD4+ T cells perceive a positively selecting class II MHC/peptide complex in the periphery.
abstract: A repertoire of TCRs is selected in the thymus by interactions with MHC bound to self-derived peptides. Whether self peptides bound to MHC influence the survival of mature T cells in the periphery remains enigmatic. In this study, we show that the number of naive CD4+ T cells that developed in mice with class II MHC bound with endogenous peptides (Abwt) diminished when transferred into mice with Ab covalently bound with a single peptide (AbEp). Moreover, transfer of a mixture of naive CD4+ T cells derived from Abwt and from AbEp mice into AbEp mice resulted in the expansion of the latter and decline of the former. In contrast, when wild-type activated CD4+ T cells were transferred into AbEp or Abwt mice, these cells survived in both recipients for more than 4 wk, but further expanded in the Abwt host. We conclude that to survive, naive CD4+ T cells favor peripheral expression of the class II MHC/peptide complex(es) involved in their thymic selection, whereas some of activated CD4+ T cells may require them only for expansion.
authors.affiliation: Institute of Molecular Medicine and Genetics, Medical College of Georgia, Augusta, GA 30912, USA.
authors.forename: P
authors.initials: P
authors.lastname: Muranski
authors.forename: B
authors.initials: B
authors.lastname: Chmielowski
authors.forename: L
authors.initials: L
authors.lastname: Ignatowicz
mesh_terms: D019264:Adoptive Transfer; D000818:Animals; D016026:Bone Marrow Transplantation / Q000276:immunology; D015496:CD4-Positive T-Lymphocytes / Q000166:cytology* / Q000378:metabolism / Q000528:radiation effects / Q000637:transplantation*; D002450:Cell Communication / Q000276:immunology; D002454:Cell Differentiation / Q000276:immunology; D002470:Cell Survival / Q000276:immunology / Q000528:radiation effects; D000949:Histocompatibility Antigens Class II / Q000096:biosynthesis / Q000276:immunology* / Q000378:metabolism; D007399:Interphase / Q000276:immunology; D008024:Ligands; D008213:Lymphocyte Activation; D051379:Mice; D020297:Mice, Congenic; D008810:Mice, Inbred C57BL; D010455:Peptides / Q000276:immunology* / Q000378:metabolism; D011485:Protein Binding / Q000276:immunology; D011828:Radiation Chimera; D013950:Thymus Gland / Q000166:cytology / Q000276:immunology
chemical_list: D000949:Histocompatibility Antigens Class II; D008024:Ligands; D010455:Peptides