Figure 2.

Representative images of characterizations of the human mesenchymal stem cells. (A) Immunocytochemical assays show that hMSCs expressed the known MSC-associated markers (CD73, CD90, and CD105), but not leukocyte marker CD45; (B) Chondrogenic cell pellets were positively stained with toluidine blue for PGs, and via immunohistochemistry for type II collagen; (C) Osteogenic cells in the monolayer culture were stained for alkaline phosphatase activity (ALP), and the adipogenic cells with Oil Red O (ORO) staining. The differentiation assays were performed separately for the cells collected from three different donors.