[A study of injectable autogenous tissue-engineered bone].
OBJECTIVE: To investigate the utilization of carrier for delivering osteoblasts and creating autogenous bone tissue in ectopic site of animal via injection. METHODS: Bone 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. RESULTS: Four, 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. CONCLUSIONS: These results demonstrate that new bone tissue could be created through the injection of alginate sodium treated with autogenous marrow stromal osteoblasts.