title: Altered major histocompatibility complex-restricted antigen recognition by T cells from elderly humans.
abstract: Positive selection of T cells within the thymus gland leads to major histocompatibility complex (MHC)-restricted recognition of antigen by T lymphocytes. As the thymus gland involutes with age, altered MHC-restricted antigen recognition by T cells from elderly humans would be expected. We have tested this hypothesis by comparing the proliferative response of T cells and T cell clones from aged and young subjects to influenza determinants presented by autologous or allogeneic antigen-presenting cells (APC). Under conditions in which the allogeneic mixed lymphocyte reaction was minimal, T cells from six of seven aged donors but only one of seven young donors were stimulated by influenza vaccine presented by allogeneic APC. More importantly, one-half of the influenza-specific T cell clones derived from aged donors, but none of the clones derived from young donors, were activated by influenza vaccine presented by allogeneic APC. While 80% of the MHC-nonrestricted influenza-specific T cell clones expressed the gamma/delta T cell receptor, 20% of these clones expressed the alpha/beta T cell receptor. Thus, changes in MHC-restricted antigen recognition by T cells and in altered distribution of alpha/beta versus the gamma/delta T cell receptor bearing antigen-specific T cell clones occur with aging.
authors.affiliation: Department of Medicine, Cornell University Medical College, New York, NY 10021.
authors.forename: R
authors.initials: R
authors.lastname: Schwab
authors.forename: C
authors.initials: C
authors.lastname: Russo
authors.forename: M E
authors.initials: ME
authors.lastname: Weksler
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D000375:Aging / Q000276:immunology*; D000938:Antigen-Presenting Cells / Q000502:physiology; D000941:Antigens / Q000276:immunology*; D006801:Humans; D007252:Influenza Vaccines / Q000276:immunology; D008213:Lymphocyte Activation; D008285:Major Histocompatibility Complex / Q000276:immunology*; D016692:Receptors, Antigen, T-Cell, gamma-delta / Q000032:analysis; D013601:T-Lymphocytes / Q000276:immunology*
chemical_list: D000941:Antigens; D007252:Influenza Vaccines; D016692:Receptors, Antigen, T-Cell, gamma-delta