title: CD4+ T cells are able to reject class I disparate allografts.
abstract: The ability of CD4+ T cells to reject class I mismatched skin allografts remains controversial. In this study, we compare the ability of CD4+ T cells to reject class I disparate skin grafts differing by either a single class I allelic disparity or only 3 amino acids encoded by the H-2K locus. We demonstrate that skin grafts across a full H-2K allelic disparity, but not across a disparity of only three amino acids are efficiently rejected by CD4+ T cells. This observation is consistent with the possibility that peptides derived from allogeneic class I molecules generated through the major histocompatibility complex (MHC) class II antigen processing pathway can be recognized by host CD4 T cells and lead to rejection of class I mismatched skin grafts. The availability of peptides derived from allogeneic MHC class I molecules for presentation by host MHC class II may determine the efficiency of rejection of class I mismatched allografts by CD4+ T cells. Thus, class I mismatched allografts can be rejected by CD4+ T cells provided that host and donor MHC class I molecules are sufficiently disparate to activate CD4+ effectors.
authors.affiliation: Transplantation Biology Research Center, Massachusetts General Hospital, and Harvard Medical School, Boston 02129, USA.
authors.forename: T
authors.initials: T
authors.lastname: Sawada
authors.forename: Y
authors.initials: Y
authors.lastname: Wu
authors.forename: D H
authors.initials: DH
authors.lastname: Sachs
authors.forename: J
authors.initials: J
authors.lastname: Iacomini
mesh_terms: D000818:Animals; D015496:CD4-Positive T-Lymphocytes / Q000502:physiology*; D018414:CD8-Positive T-Lymphocytes / Q000502:physiology; D005260:Female; D006084:Graft Rejection / Q000276:immunology; D006087:Graft vs Host Reaction; D015395:Histocompatibility Antigens Class I / Q000276:immunology*; D051379:Mice; D008810:Mice, Inbred C57BL; D008815:Mice, Inbred Strains; D016038:Skin Transplantation / Q000276:immunology*
chemical_list: D015395:Histocompatibility Antigens Class I