[Implantation of pyrolyzed calf bone along with osteoblasts cultured in vitro]

The regeneration of osseous tissues after simultaneous implantation of rat osteoblast-like cells cultured in vitro and pyrolyzed calf bone was investigated. In this study a cell line of rat osteoblast-like cells originating from explants of 2 inbred rats (Lewis) was established and cells were characterized. The osteoblast-like cells were cultured in vitro, embedded in bovine bone gelatine after 3 passages in culture and then implanted together with pyrolyzed calf bone in artificial femur defects of the inbred Lewis rats. After 10, 20, 40 and 80 days animals were sacrificed and the treated femora were taken for histological examination of bone growth. It was demonstrated that the cultured osteoblast-like cells showed an activity by forming extracortical bone, but had no measurable effect on bone growth pattern in the defects. Since our former animal study on reimplantation of osteoblast-like cells had revealed an effect on the cells on bone growth pattern, it is discussed whether the present lack of this effect can be explained by simultaneous implantation of xenogenic bone. In view of the importance of bone regeneration, autologous reimplantation of cultured bone cells deserves further investigation.