Experimental Study On Autotransplanted Osteogenesis Within Musle Combined By Mesenchymal Stem Cells And Coralline Hydroxyapatite

Objectives:To investigate a methods system for the separation,culture and identification of MSCs from rabbits in vitro; to investigate the biocompatibility and osteogenesis capability of CHA compound with MSCs from rabbits and to evaluate the feasibility of constructing tissue engineering bone with them and their practical value in clinic.Methods:1 To establish a methods system for the separation,culture and identification of MSCs from rabbits in vitro.MSCs was harvested from crista iliaca. Bone marrow aspirate of rabbit was density gradient centrifuged and cultured in plastic culture bottles. The cells were examined by invert microscope. The growth curve was drawn and cell doubling time,confluent rate was measured. MSCs quality was evaluated with immunocyto- chemistry, and their phenorypical properties were known. performed, there is statistical significance if P<0.05.2 The experimental study of CHA combine with MSCs from rabbits on biocompatibility and osteogenic capability .CHA with osteoblastes, that were differenciated from marrow cells of rabbits, were autotransplanted within dorsal muscle of rabbits. Meanwhile, samples of CHA alone were implanted as the negative control group. The specimens were retrieved at 4 and 8 weeks. The bone formation was assessed by morphologic means (light microscopy examination).Reults:1 MSCs had soindle shape and a typical morphological fibroblast. The primary cells were confluent in single layer after being plated for 12-15days. The cells were noted to have a grate expansive potential after subculture. The average time for cell doubling was 34 hours.The proliferation ability declined with time of the culture. About 90% subcultured cells dahered the wall in 12h. MSCs uniformly expression of CD44 and did no expression of CD34.2 At both time, formation of new bone were observed in the osteoblasts/CHA composites of rabbits model. In CHA alone groups, the histologic features of all of control specimens demonstrated no new bone formation.Conclutions :1 The combination of density gradient centrifugation and adhere culture is an effective method to isolate MSCs from bone marrow. MSCs culture is vito show stable growth, rapid proliferation and 1 to 5 passage can be used as seed cells in cartilage tissue engineering. The surface antigens, which are positive for CD44 and negative for CD34, are a method for identification of MSCs.2 Osteogenesis could be sbserved in CHA seeded with osteoblasts. Therefore, osteoblasts/CHA composite presented a promising prospect for clinical practice. CHA possesses good biocompatibility, osteoconduction and porous stucture, can be used as scaffold material for constructing of tissue engineering bone.