title: Phenotype and function of a CD56+ peripheral blood monocyte.
abstract: G-CSF primed CD34 cells cultured for 2-3 weeks in IL-2 and stem cell factor generate CD56(high) cells with phenotypic and morphologic features of NK cells, and a novel adherent CD56(low) CD16- population expressing myeloid markers (CD33 and HLA-DR). We hypothesized that similar cells might also occur in peripheral blood. In 13/13 normal individuals, we found a circulating population of CD56(low), CD33+, FcgammaRI+, FcgammaRII+, HLA-DR+, CD11b(high), CD14+ monocytes closely resembling the cultured CD56(low)CD33+ cells. They may represent a normal counterpart of the CD56+ CD33+ hybrid myeloid/natural killer cell leukemia. Their mean frequency was 1.3+/-1% (standard deviation), range 0.16-3.5%, of total mononuclear cells. CD56(low)CD33+ cells, primed with cytomegalovirus antigen, induced autologous T-lymphocyte proliferation comparably to CD56-, CD14+ peripheral blood monocytes (PBM). Conversely, CD56(low) cells induced greater T-cell proliferation than CD56- PBM when lymphocyte responders were HLA mismatched. Unstimulated CD56(low)CD33+ cells showed a low antiproliferative effect on K562, which was increased upon LPS stimulation. The pattern of cytokine production by CD56(low)CD33+ cells and PBM largely overlapped; however, they produced detectable levels of IL-6 and IL-1beta. These results define a minor monocyte population with distinct phenotypic and functional features.
authors.affiliation: Stem Cell Allotransplantation Section, Hematology Branch, National Heart Lung and Blood Institute, National Institutes of Health, Bethesda, MD, USA.
authors.forename: G
authors.initials: G
authors.lastname: Sconocchia
authors.forename: K
authors.initials: K
authors.lastname: Keyvanfar
authors.forename: F
authors.initials: F
authors.lastname: El Ouriaghli
authors.forename: M
authors.initials: M
authors.lastname: Grube
authors.forename: K
authors.initials: K
authors.lastname: Rezvani
authors.forename: H
authors.initials: H
authors.lastname: Fujiwara
authors.forename: J P
authors.initials: JP
authors.lastname: McCoy
authors.forename: N
authors.initials: N
authors.lastname: Hensel
authors.forename: A J
authors.initials: AJ
authors.lastname: Barrett
mesh_terms: D019002:CD56 Antigen / Q000276:immunology*; D005434:Flow Cytometry; D006801:Humans; D007375:Interleukin-1 / Q000378:metabolism; D015850:Interleukin-6 / Q000378:metabolism; D009000:Monocytes / Q000276:immunology*; D010641:Phenotype
chemical_list: D019002:CD56 Antigen; D007375:Interleukin-1; D015850:Interleukin-6