[Preparation of a biphasic calcined bone of beta-TCP/HAP and its application in BMP-2 gene medicine].

In this study, we produced a biphasic absorbable calcined bone (CB) of beta-TCP/HAP, and evaluated its function as a carrier of bone marrow derived mesenchymal stem cells(BMSCs) in BMP-2 gene medicine. Biphasic CB was manufactured and its surface was coated by collagen. X-ray diffraction analysis, scanning electron microscopy and biomechanical measurement were performed on the product. Heterotopic bone induction of product as carrier of BMP-2 gene transferred BMSCs and its biodegradability were tested in nude mice and goats. X-ray diffraction analysis showed biphasic patterns of HAP and beta-TCP. Scanning electron microscopy showed the porosity were similar to those of the cancellous bone, and the adhesion of cells on the CB surface were better after surface-coating with collagen. It had certain biomechanical strength and appropriate biodegradability. Biphasic CB loaded with Adv-hBMP-2 transduced BMSCs could induce much bony callus at the subcutaneous site of nude mice and the tibial bone defects of goats. The results showed biphasic CB is a superior carrier of cells in BMP-2 gene medicine.