[Ectopic bone formation by composite graft of culture-expanded human marrow cells and porous calcium phosphate ceramic]

Abstract

Human bone marrow cells derived from three different sources; (1) cancellous bone of the femur; (2) cancellous bone of the rib from cadavers; (3) aspirate from the iliac bone were introduced into tissue culture. The adherent cells were cultivated, mitotically expanded, passaged, harvested then placed in small cubes of porous calcium phosphate ceramics and finally grafted into subcutaneous sites of athymic mouse or athymic rat. The ceramics loaded with cultured marrow cells from cancellous bone of femur showed strong osteogenic potential with bone forming in the pore regions of ceramics as early as two weeks after in vivo implantation. Osteogenesis could be observed after seventh passage (Five times passaged, frozen, stored, thawed, and replated twice). Although the aspirated marrow cells cultured also exhibited bone formation, the osteogenesis initiated later and the bone formation rate was lower. The ceramics loaded with fresh red blood cells separated from the aspirated marrow showed no evidence of bone formation. Moreover, osteogenic cells were found to have an ability to proliferate selectively in tissue culture.