title: Analysis of CD16+dim and CD16+bright lymphocytes--comparison of peripheral and clonal non-MHC-restricted T cells and NK cells.
abstract: The Fc gamma RIII receptor (CD16) has been described on natural killer cells and a small subset of T lymphocytes. CD16+bright lymphocytes represent the typical population of peripheral blood CD3- NK cells. In these studies in addition to CD16+bright NK cells Fc gamma RIII expressing cytotoxic T lymphocytes in peripheral blood from one healthy individual are characterized as CD16+dim non-MHC-restricted CTLs either expressing the alpha/beta (80%) or the gamma/delta T cell receptor (20%). Both CD16+ subsets are clearly distinct in their functional capacity performing NK and ADCC activity. Freshly isolated CD16+dim T cells exert higher ADCC, CD16+bright NK cells higher NK activity. They are also differentially activated by interleukin-2 since CD16+bright NK cells reveal a bright expression of the p75 IL-2 receptor beta-chain in contrast to the very low p75 expression on CD16+dim T cells. This activation leads to a gradual increase of ADCC by NK cells. Finally the CD16 expression pattern with low and bright intensity represents a stable phenotype expressed by clones generated from these different subpopulations. On a clonal level CD16+dim non-MHC-restricted T cells can be distinguished from CD16+bright NK cells by their lower capacity in NK killing, but they are equally potent in ADCC. Finally these CD3+CD16+dim clones provide the basis for studies of Fc gamma RIII and TcR interaction.
authors.affiliation: Abteilung Immunologie und Transfusionsmedizin, Medizinische Hochschule Hannover, Germany.
authors.forename: P
authors.initials: P
authors.lastname: Uciechowski
authors.forename: T
authors.initials: T
authors.lastname: Werfel
authors.forename: R
authors.initials: R
authors.lastname: Leo
authors.forename: J E
authors.initials: JE
authors.lastname: Gessner
authors.forename: J
authors.initials: J
authors.lastname: Schubert
authors.forename: R E
authors.initials: RE
authors.lastname: Schmidt
mesh_terms: D000920:Antibody-Dependent Cell Cytotoxicity; D002469:Cell Separation; D002999:Clone Cells / Q000737:chemistry; D003601:Cytotoxicity Tests, Immunologic; D005434:Flow Cytometry; D006801:Humans; D016130:Immunophenotyping; D007694:Killer Cells, Natural / Q000737:chemistry / Q000276:immunology*; D008213:Lymphocyte Activation; D017452:Receptors, IgG / Q000032:analysis*; D013602:T-Lymphocytes, Cytotoxic / Q000737:chemistry / Q000276:immunology*; D014158:Transcription, Genetic
chemical_list: D017452:Receptors, IgG