Effects of osteogenic growth factors on bone marrow stromal cell differentiation in a mineral-based delivery system.
Delivering growth factors from bone-like mineral combines osteoinductivity with osteoconductivity. The effects of individual and sequential exposure of BMP-2 and FGF-2 on osteogenic differentiation, and their release from apatite were studied to design a dual delivery system. Bone marrow stromal cells were seeded on TCPS with the addition of FGF-2 (2.5, 10, 40 ng/ml) or BMP-2 (50, 150, 450 ng/ml) for 6 days. DNA content and osteogenic response were examined weekly for 3 weeks. FGF-2 increased DNA content; however, high concentrations of FGF-2 inhibited/delayed osteogenic differentiation, while a threshold concentration of BMP-2 was required for significant osteogenic enhancement. The sequence of delivery of BMP-2 (300 ng/ml) and FGF-2 (2.5 ng/ml) also had a significant impact on osteogenic differentiation. Delivery of FGF-2 followed by BMP-2 or delivery of BMP-2 followed by BMP-2 and FGF-2 enhanced osteogenic differentiation compared to the simultaneous delivery of both factors. Release of BMP-2 and FGF-2 from bone-like mineral was significantly affected by the concentration used during coprecipitation. BMP-2 also demonstrated a higher "burst" release compared to FGF-2. By integrating the results of the sequential delivery of BMP-2 and FGF-2 in solution, with the release of individual growth factors from mineral, an organic/inorganic delivery system based on coprecipitation can be designed for multiple biomolecules.
Biomedical Engineering, University of Michigan, Ann Arbor, MI 48109, USA.
Linh N
LN
Luong
Janani
J
Ramaswamy
David H
DH
Kohn
D000818:Animals; D001854:Bone Marrow Cells / Q000166:cytology*; D055396:Bone Morphogenetic Protein 2 / Q000494:pharmacology; D002454:Cell Differentiation / Q000187:drug effects*; D002478:Cells, Cultured; D016222:Fibroblast Growth Factor 2 / Q000494:pharmacology; D051379:Mice; D008810:Mice, Inbred C57BL; D010012:Osteogenesis / Q000187:drug effects*; D017154:Stromal Cells / Q000166:cytology* / Q000187:drug effects
D055396:Bone Morphogenetic Protein 2; D016222:Fibroblast Growth Factor 2