Phenotype and function of a CD56+ peripheral blood monocyte.
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.
Sconocchia
G
G
Stem Cell Allotransplantation Section, Hematology Branch, National Heart Lung and Blood Institute, National Institutes of Health, Bethesda, MD, USA.
Keyvanfar
K
K
El Ouriaghli
F
F
Grube
M
M
Rezvani
K
K
Fujiwara
H
H
McCoy
J P
JP
Hensel
N
N
Barrett
A J
AJ
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
D019002:CD56 Antigen; D007375:Interleukin-1; D015850:Interleukin-6