title: Cutting edge: cytolytic effector function in human circulating CD8+ T cells closely correlates with CD56 surface expression.
abstract: Recent data suggest that human effector CD8+ T cells express a distinct CD27-CD45RAhigh (CD57+CD28-CD11ahigh) phenotype. Here, we propose that CTL effector function correlates better with CD56 (neuronal cell adhesion molecule (NCAM)) surface expression. CD56 was absent on cord blood CD8+ T cells, but was expressed by 4-30% of freshly isolated circulating CD8+ T cells from 15 adults. Dramatic oligoclonal expansions in 3/3 individuals were confined to the CD56+ subset of CD8+ T cells. The CD56+ subset generally contained high amounts of intracellular perforin and granzyme B. Finally, direct cytolytic capacity was closely restricted to the CD56+(CD45RAhigh) cells, better than to CD27-CD45RAhigh cells in 5/5 individuals analyzed. Thus, the phenotype corresponding to the circulating effector CD8+ T cell pool may be simplified and more precisely defined by the use of just two surface markers: CD8 and CD56.
authors.affiliation: Division of Clinical Onco-Immunology, Ludwig Institute for Cancer Research, Lausanne Branch, Lausanne, Switzerland.
authors.forename: M J
authors.initials: MJ
authors.lastname: Pittet
authors.forename: D E
authors.initials: DE
authors.lastname: Speiser
authors.forename: D
authors.initials: D
authors.lastname: Valmori
authors.forename: J C
authors.initials: JC
authors.lastname: Cerottini
authors.forename: P
authors.initials: P
authors.lastname: Romero
mesh_terms: D000328:Adult; D015415:Biomarkers / Q000097:blood; D019002:CD56 Antigen / Q000096:biosynthesis*; D018414:CD8-Positive T-Lymphocytes / Q000166:cytology / Q000276:immunology* / Q000378:metabolism; D002455:Cell Division / Q000276:immunology; D002462:Cell Membrane / Q000276:immunology / Q000378:metabolism; D002999:Clone Cells; D003602:Cytotoxicity, Immunologic / Q000276:immunology*; D053804:Granzymes; D006801:Humans; D016130:Immunophenotyping; D007231:Infant, Newborn; D008562:Membrane Glycoproteins / Q000378:metabolism; D054353:Perforin; D052899:Pore Forming Cytotoxic Proteins; D012697:Serine Endopeptidases / Q000378:metabolism; D016176:T-Lymphocyte Subsets / Q000166:cytology / Q000276:immunology* / Q000378:metabolism
chemical_list: D015415:Biomarkers; D019002:CD56 Antigen; D008562:Membrane Glycoproteins; D052899:Pore Forming Cytotoxic Proteins; D054353:Perforin; C509213:GZMB protein, human; D053804:Granzymes; D012697:Serine Endopeptidases