Figure 1.

(A) Identification of one CD14+ monocyte subset DC-STAMP+CD45^int that is present in human bone marrow but absent in the peripheral blood. Monocytes isolated from bone marrow (BM) and peripheral blood (PBMC) were stained with an 11-color antibody cocktail and analyzed by flow analysis. CD14+ monocytes in PBMC (a) and BM (b) were analyzed by the cell surface expression of DC-STAMP (X-axis) and CD45 (Y-axis). The DC-STAMP+CD45^int cell population was located by red arrows. Three cell populations DC-STAMP+CD45+, DC-STAMP+CD45^int; and DC-STAMP+CD45− were labeled with (i), (ii), and (iii), respectively. Data shown were live cells after dead cells and doublet exclusion. Representative of 6 subjects including 3 healthy controls and 3 patients with psoriatic diseases.

(B) More non-traditional CD14+CD16+ monocytes reside in human bone marrow than peripheral blood. Cells were isolated from peripheral blood (a) and bone marrow (b), stained with one 11-color antibody cocktail, and analyzed by flow cytometry.

(C) Human bone marrow is the major reservoir of ostoeclast precursors (OCPs). Numbers of osteoclasts derived from enriched monocytes purified from human peripheral blood and bone marrow. Enriched monocytes were isolated from peripheral blood and bone marrow, cultured in OC-promoting media (RANKL+M-CSF) for 8 days, and TRAP-stained for OC enumeration. Enriched monocytes has a purity >80%.