title: CD28(-)CD8(+) T cells do not contain unique clonotypes and are therefore dispensable.
abstract: Highly differentiated CD28(-) effector T cells which accumulate in a variety of diseases and also with increasing age contribute to inflammatory processes, limit immunological space and diversity, and are associated with immunological dysfunction and reduced responses to vaccination. Elimination of CD28(-) T cells has been suggested as a measure for immunological rejuvenation but may lead to the loss of important T cell specificities. Using T cells specific for the immunodominant CMV-derived epitope NLVPMVATV as a model, we show that the same clonotypes are present in CD8(+)CD28(+) naïve/early memory and CD8(+)CD28(-) effector T cells. Therefore, CD28(-) cells do not seem to contain clones which are not present in the residual population. The elimination of effector T cells would not lead to the loss of important specificities, as relevant clonotypes could be recruited and propagated from naïve or early memory T cell subsets in the case of exposure to pathogen.
authors.affiliation: Institute for Biomedical Aging Research, Austrian Academy of Sciences, Rennweg 10, 6020 Innsbruck, Austria.
authors.forename: Birgit
authors.initials: B
authors.lastname: Weinberger
authors.forename: Kathrin
authors.initials: K
authors.lastname: Welzl
authors.forename: Dietmar
authors.initials: D
authors.lastname: Herndler-Brandstetter
authors.forename: Walther
authors.initials: W
authors.lastname: Parson
authors.forename: Beatrix
authors.initials: B
authors.lastname: Grubeck-Loebenstein
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D019588:Aging, Premature / Q000097:blood / Q000276:immunology* / Q000473:pathology / Q000517:prevention & control; D000956:Antigens, Viral / Q000276:immunology; D018106:CD28 Antigens / Q000096:biosynthesis; D018414:CD8-Positive T-Lymphocytes / Q000276:immunology / Q000378:metabolism* / Q000473:pathology; D016922:Cellular Senescence; D002999:Clone Cells; D006801:Humans; D016056:Immunodominant Epitopes / Q000276:immunology; D007156:Immunologic Memory; D018189:Immunomagnetic Separation; D008212:Lymphocyte Depletion; D037182:T-Cell Antigen Receptor Specificity; D016176:T-Lymphocyte Subsets / Q000276:immunology / Q000378:metabolism* / Q000473:pathology
chemical_list: D000956:Antigens, Viral; D018106:CD28 Antigens; D016056:Immunodominant Epitopes