Fig. 4.

Bone marrow-derived mesenchymal stem cell (BM-MSC) differentiation on differently treated titanium disks. A. Flow cytometry of typical CD markers present on BM-MSCs cultured on the Col-, Col/nHAp-, or Col/nHAp/BMP-2-coated titanium disks. CD73+, CD90+, and CD105+ cells were observed prior to differentiation. Reduction in mesenchymal CD73+, CD90+, and CD105+ cells was observed in the Col/nHAp/BMP-2 group. B. Biochemical assays for alkaline phosphatase (ALP) activity and intracellular glycosaminoglycan (GAG) and osteopontin expression in BM-MSCs. Cells on Col/nHAp/BMP-2 exhibited the highest expression. C. mRNA expression of different osteoblastic markers in BM-MSC. The highest expression was observed for type III collagen (Col III), osteocalcin, and osteoprotegerin in cells grown on Col/nHAp/BMP-2. The levels of type I collagen (Col I), osteopontin, osteonectin, and BMP-2 expression were higher in BM-MSCs on Col/nHAp and Col/nHAp/BMP-2 than in those with Col enrichment. (Col: collagen, nHAp: nano-hydroxyapatite, BMP-2: bone morphogenetic protein-2)