[In vivo endochondral bone formation by implanting human bone morphogenetic protein-2-producing fibroblasts into nude mouse muscle]

To determine whether fibroblasts can be used to promote endochondral bone formation in vivo by transfer of human bone morphogenetic protein-2(hBMP-2) into fibroblasts.

pcDNA3-hBMP-2 was constructed by use of gene clone and recombined technique. NIH3T3 fibroblasts were transfected with pcDNA3-hBMP-2. The positive cell clones were selected with G418. In NIH3T3 fibroblasts transferred with pcDNA3-hBMP-2, the expression of hBMP-2 was determined by in situ hybridization and immunohistochemical analysis; alkaline phosphatase activity was measured. hBMP-2-producing fibroblasts were implanted into nude mouse muscle to observe endochondral bone formation in vivo.

pcDNA3-hBMP-2 was successfully constructed. In NIH3T3 fibroblasts transfected with pcDNA3-hBMP-2, the BMP-2 expression was stable; alkaline phophatase activity was much higher than that in non-transfected NIH3T3 cells. Endochondral bone formation in vivo was observed at the site of implantation 4 weeks later.

Fibroblasts transfected by hBMP-2 gene can be used to promote endochondral bone formation in vivo.