title: IFN-mediated induction of MHC antigen expression on human keratinocytes and its influence on in vitro alloimmune responses.
abstract: The MHC Ag expression on the surface of keratinocytes is altered after treatment with IFN. IFN-gamma induces, as expected, a strong increase in class I MHC Ag expression as well as de novo expression of class II MHC Ag, whereas IFN-alpha 2 only slightly increases class I MHC Ag and does not induce keratinocytes to express class II MHC Ag. We used untreated and IFN-pretreated keratinocytes as stimulators and also as targets to study whether IFN-induced MHC Ag changes would alter the immunogenicity of keratinocytes in alloimmune responses. It was found that class II MHC Ag-carrying keratinocytes were unable to induce the proliferation of resting lymphocytes, but did stimulate T blasts. Untreated keratinocytes were virtually resistant to the lysis by classical CTL but became susceptible after exposure to IFN-gamma, but not IFN-alpha 2 at physiologic doses. These data demonstrate mechanisms by which the release of IFN-gamma might contribute to the development of disease such as the graft vs host disease.
mesh_terms: D002455:Cell Division; D003601:Cytotoxicity Tests, Immunologic; D000078404:Epidermal Cells; D004817:Epidermis / Q000187:drug effects* / Q000276:immunology; D005786:Gene Expression Regulation / Q000187:drug effects; D006649:Histocompatibility Antigens / Q000096:biosynthesis*; D006801:Humans; D007156:Immunologic Memory; D007372:Interferons / Q000494:pharmacology*; D013602:T-Lymphocytes, Cytotoxic / Q000276:immunology
chemical_list: D006649:Histocompatibility Antigens; D007372:Interferons