Objective: To investigate the osteogenic capability of primary human adipose-derived stromal cells (hASCs) in vivo.
Methods: hASCs were isolated from adipose tissue by the method of collagenase digestion. After 7 and 14 days of osteogenic induction, alkaline phosphatase (ALP) staining and Alizarin Red staining were performed to test the osteogenic potential of hASCs in vitro. After 14 days of adipogenic induction, the adipogenic potential of hASCs was assayed by Oil Red O staining.In the in vivo part, 12 nude mice were used. Test group (scaffold with hASCs) and control group (scaffold only) were symmetrically implanted into the back of nude mice. After 4 weeks and 8 weeks of implantation, samples were collected. Histological and immunohistochemical staining were performed to investigate the osteogenic capability of hASCs.
Results: Approximately 6×10(7) hASCs could be isolated from 300 mL adipose tissue. ALP, Alizarin Red and Oil Red O staining of hASCs showed positive results after specific inductions. These results demonstrated the osteogenic and adipogenic potentials of hASCs in vitro. Bone-like tissue could be observed in the test group at 4 weeks and 8 weeks after the implantation. Immunohistochemical staining showed that there were positive results of osteocalcin, ALP and anti-human nuclei in the bone-like tissue areas.
Conclusion: A large number of primary hASCs can be isolated from human adipose tissue; hASCs combined with scaffold show osteogenic capability in vivo.