title: Subsets of CD8+, CD57+ cells in normal, healthy individuals: correlations with human cytomegalovirus (HCMV) carrier status, phenotypic and functional analyses.
abstract: Two different subsets of CD8+, CD57+ cells have been defined, one expressing high levels (CD8high+(CD57+)), the other expressing low levels of surface CD8 (CD8low+(CD57+)). Increased numbers of CD8high+(CD57+) cells correlated with previous HCMV infection. By three-colour fluorescence analysis, the CD8high+(CD57+) population expressed T cell markers such as CD3 and CD5, and most were alpha beta T cell receptor (alpha beta TCR)-positive. A significant proportion also expressed CD71 (transferrin receptor) and MHC class I, although little if any CD25 (IL-2R-p55). Some (> or = 40%) co-expressed CD45RA and CD45RO. The CD8low+(CD57+) population expressed classical natural killer (NK) cell markers--CD2, CD16 and CD56. The two subsets were also functionally distinct; CD8high+(CD57+) cells suppressed pokeweed mitogen (PWM)-driven, but not phytohaemagglutinin (PHA)-driven proliferation and immunoglobulin production; CD8low+(CD57+) cells exhibited NK cytotoxic activity which was not increased by interferon-alpha (IFN-alpha). Supernatant from cultured CD8high+(CD57+) cells suppressed PWM-driven immunoglobulin production, but not proliferation, and this effect was abrogated by physical separation with tissue culture inserts. Thus, a T cell subset expressing activation and memory T cell markers with direct non-specific suppressor activity was present in peripheral blood mononuclear cells (PBMC) of healthy subjects with asymptomatic HCMV infection.
authors.affiliation: Department of Medicine, University of Wales College of Medicine, Health Hospital, Cardiff, UK.
authors.forename: E C
authors.initials: EC
authors.lastname: Wang
authors.forename: J
authors.initials: J
authors.lastname: Taylor-Wiedeman
authors.forename: P
authors.initials: P
authors.lastname: Perera
authors.forename: J
authors.initials: J
authors.lastname: Fisher
authors.forename: L K
authors.initials: LK
authors.lastname: Borysiewicz
mesh_terms: D015703:Antigens, CD / Q000378:metabolism*; D000945:Antigens, Differentiation, T-Lymphocyte / Q000378:metabolism*; D018959:CD57 Antigens; D016827:CD8 Antigens / Q000378:metabolism*; D002353:Carrier State / Q000276:immunology*; D003586:Cytomegalovirus Infections / Q000276:immunology*; D003602:Cytotoxicity, Immunologic; D005434:Flow Cytometry; D006801:Humans; D007136:Immunoglobulins / Q000096:biosynthesis; D007694:Killer Cells, Natural / Q000276:immunology; D008213:Lymphocyte Activation; D016131:Lymphocyte Subsets / Q000276:immunology*; D010641:Phenotype; D011043:Pokeweed Mitogens / Q000494:pharmacology; D050378:T-Lymphocytes, Regulatory / Q000276:immunology
chemical_list: D015703:Antigens, CD; D000945:Antigens, Differentiation, T-Lymphocyte; D018959:CD57 Antigens; D016827:CD8 Antigens; D007136:Immunoglobulins; D011043:Pokeweed Mitogens