OBJECTIVETo investigate the utilization of carrier for delivering osteoblasts and creating autogenous bone tissue in ectopic site of animal via injection.

METHODSBone marrow cells harvested from iliac bone of New Zealand rabbits were induced to differentiate into marrow stromal osteoblasts. The osteoblasts were mixed with 1.5% alginate sodium solution to generate osteoblasts/alginate composites with final cellular density of 4 x 10(9)/L. Calcium chloride was used as cross-linking agent to gel aqueous alginate solution. The marrow stromal osteoblasts/alginate composites were injected into the dorsal subcutaneous tissue of rabbits with autogenous cells transplantation. The samples were examined with X-ray and histological analysis.

RESULTSFour, eight and twelve weeks after injection, the hard knobbles were easily palpated under the dorsal skin of animals. On X-ray photograph the samples showed calcified image with more density than surrounding soft tissue, new bone formation was observed in the osteoblasts/alginate composites in histological analysis. The osteogenesis was in association with regenerated hematopoietic bone marrow.

CONCLUSIONSThese results demonstrate that new bone tissue could be created through the injection of alginate sodium treated with autogenous marrow stromal osteoblasts.