DEMONSTRATION OF FUNCTIONALLY DISTINCT HUMAN POLYMORPHONUCLEAR LEUKOCYTE FRACTIONS BY SIMULTANEOUS MEASUREMENT OF PHAGOCYTOSIS AND OXYGEN RADICAL GENERATION
K. Takano et al., DEMONSTRATION OF FUNCTIONALLY DISTINCT HUMAN POLYMORPHONUCLEAR LEUKOCYTE FRACTIONS BY SIMULTANEOUS MEASUREMENT OF PHAGOCYTOSIS AND OXYGEN RADICAL GENERATION, International journal of hematology, 66(1), 1997, pp. 69-78
Phagocytosis and oxygen radical generation by human polymorphonuclear
leukocytes (PMNLs) were studied by a two-color flow cytometric analysi
s, where the red fluorescent product(s) of hydroethidine was used as a
n indicator of intracellular generation of oxygen radicals and opsoniz
ed zymosan (OZ) as an indicator of phagocytosis. Unstimulated cells fo
rmed a single population of cells without any significant fluorescence
. PMNLs stimulated by OZ exhibited a high red fluorescence. Most PMNLs
phagocytosed OZ and generated oxygen radicals when stimulated by zymo
san particles opsonized with human AB serum at concentrations of more
than 10%, whereas three distinct subpopulations (designated as R1, R2
and R3) appeared when stimulated by zymosan particles opsonized with 3
% serum; R1 cells enhanced neither green nor red fluorescence, R2 cell
s enhanced green fluorescence but not red fluorescence, and R3 cells e
nhanced both green and red fluorescence. The R2 cells completely disap
peared by the addition of Trypan blue. Most of the R3 cells disappeare
d by the addition of cytochalasin B. These findings on the three fract
ions were confirmed by the observation under fluorescence microscopy o
f cells in each fraction obtained by sorting. In conclusion, PMNLs cou
ld be separated into three functionally distinct subpopulations when s
timulated by zymosan particles opsonized with a suboptimal concentrati
on of serum. (C) 1997 Elsevier Science Ireland Ltd.