NORMAL HUMAN PERIPHERAL-BLOOD MONONUCLEAR-CELLS MOBILIZED WITH GRANULOCYTE-COLONY-STIMULATING FACTOR HAVE INCREASED OSTEOCLASTOGENIC POTENTIAL COMPARED TO NONMOBILIZED BLOOD
Le. Purton et al., NORMAL HUMAN PERIPHERAL-BLOOD MONONUCLEAR-CELLS MOBILIZED WITH GRANULOCYTE-COLONY-STIMULATING FACTOR HAVE INCREASED OSTEOCLASTOGENIC POTENTIAL COMPARED TO NONMOBILIZED BLOOD, Blood, 87(5), 1996, pp. 1802-1808
Single-cell suspensions of granulocyte colony-stimulating factor (G-CS
F)-mobilized peripheral blood mononuclear cells (G-PBMC) cultured in a
lpha minimal essential medium (alpha MEM) containing 10% fetal bovine
serum formed multicellular aggregates within 24 hours. In six separate
experiments, formation of aggregates appeared to be dependent on cell
density per surface area, so that 5.8 +/- 1.3 aggregates formed per 1
x 10(5) cells when G-PBMC were cultured at densities greater than or
equal to 1 x 10(5) cells/cm(2). The frequency of aggregate formation w
as less than 1 per 10(5) cells when G-PBMC were cultured at densities
less than 1 x 10(5) cells/cm(2). Once formed, aggregates became adhere
nt within 72 hours, and then, over the course of 21 days, released CD3
/CD4/CD25-positive cells into the supernatant. This T-cell production
peaked between days 7 and 14, reaching a total of 1,269 +/- 125.9 cell
s released per aggregate by day 21. Between days 14 and 21, the aggreg
ates also generated macroscopic clusters of adherent mononuclear and g
iant multinucleated cells that stained positive for tartrate-resistant
acid phosphatase (TRAP). At 4 weeks, the macroscopic foci coalesced i
nto monolayers. Multinucleated TRAP-positive cells were distinguished
from macrophage polykaryons by the absence of CD14 expression and the
presence of osteoclast-specific membrane receptors for calcitonin and
alpha(v) beta(3)-vitronectin. The osteoclast nature of these cells was
further demonstrated by their ability to form resorption lacunae on d
entine slices. Comparable osteoclast formation was not detected in cul
tures of normal marrow or normal nonmobilized peripheral blood. (C) 19
96 by The American Society of Hematology.