title: CD4 T-cell memory can persist in the absence of class II.
abstract: To understand how memory CD4 T cells are generated we have re-examined the requirements for continuing antigen stimulation in the generation and persistence of this population. We find that specific antigen is only required for a short period during the activation of naive CD4 T cells and is not required for memory generation from activated CD4 T cells or for persistence of resting memory cells generated by transfer of activated CD4 to adoptive hosts. Moreover, transfer of activated CD4 T cells to class-II-deficient hosts, indicates that TcR-class II major histocompatibility interaction is also unnecessary for either the transition from activated CD4 T cell to resting memory cells or for persistence over an eight-week period. Thus the signals regulating generation and maintenance of memory are fundamentally different from those which regulate the expansion of effector CD4 T-cell populations which include antigen itself and the CD4 T-cell autocrine cytokines induced by antigen.
authors.affiliation: Trudeau Institute, Saranac Lake, NY 12983, USA.
authors.forename: S L
authors.initials: SL
authors.lastname: Swain
mesh_terms: D000818:Animals; D015496:CD4-Positive T-Lymphocytes / Q000276:immunology*; D000949:Histocompatibility Antigens Class II / Q000276:immunology*; D006801:Humans; D007156:Immunologic Memory / Q000276:immunology*
chemical_list: D000949:Histocompatibility Antigens Class II