Isolation and Characterization of Murine Clonogenic Osteoclast
Progenitors by Cell Surface Phenotype Analysis
Yukari Muguruma and
Minako Y. Lee
From the Department of Biological Structure, University of Washington
School of Medicine, Seattle, WA.
Osteoclasts are bone resorbing cells of hematopoietic origin;
however, a progenitor cell population that gives rise to mature osteoclasts remains elusive. We have characterized a unique cell surface phenotype of clonogenic osteoclast progenitors (colony-forming unit-osteoclast [CFU-O]) and obtained a marrow cell
population selectively enriched for these progenitors. Whole bone
marrow cells were sequentially separated based on physical and cell
surface characteristics, and the presence of CFU-O and other
hematopoietic progenitors was examined. CFU-O was enriched in a
nonadherent, low-density, lineage-marker-negative
(Lin
), Thy1.2-negative (Thy1.2),
Sca1-negative (Sca1), and c-kit-positive
(c-kit+) population, as were the progenitors that were
responsive to macrophage-colony-stimulating factor(CSF; CFU-M),
granulocyte-macrophage-CSF (CFU-GM), and stem cell factor (CFU-SCF).
When the LinThy1.2Sca1
population was divided into c-kithigh and
c-kitlow populations based on c-kit fluorescence, over 88%
of CFU-M, CFU-GM, and CFU-SCF were found in the c-kithigh
population. In relation to the above mentioned hematopoietic progenitors, CFU-O was significantly higher in the c-kitlow
population: 80% of progenitors present in the c-kitlow
population were CFU-O. The CFU-O in both c-kithigh and
c-kitlow populations showed key features of the osteoclast:
multinucleated tartrate-resistant acid phosphatase-positive cell
formation, expressions of vitronectin receptors, c-src and calcitonin
receptors, and bone resorption. We have identified a progenitor cell
population in the earliest stage of the osteoclast lineage so far
described and developed a method to isolate it from other hematopoietic progenitors. This should help pave the way to understand the molecular mechanisms of osteoclast differentiation.
Blood, Vol. 91 No. 4 (February 15), 1998:
pp. 1272-1279
© 1998 by The American Society of Hematology.
