Osteogenesis by Transfer of Bone Morphogenetic Protein-2 cDNA in Ligamentum Flavum Cells: Approach Toward Tissue Engineering / 대한척추외과학회지

ABSTRACT

STUDY DESIGN: In-vitro experiment. OBJECTIVES: To determine the effect of bone morphogenetic protein-2 in the osteogenesis of human ligamentum flavum cells and test the feasibility of gene transfer to these cells. SUMMARY OF LITERATURE REVIEW Bone morphogenetic protein-2 (BMP-2) is known to be an important factor in the differentiation and maintenance of the osteoblastic phenotype. Tissue engineering for osteogenesis in ligamentum flavum by BMP-2 and gene transfer has not been previously studied. MATERIALS AND METHODS: Ligmentum flavum cells were harvested and cultured from surgical patients with spinal stenosis. BMP-2 was produced by transfecting pcDNA3.1/Hygro/BMP-2 into CHO cells using Lipofectamine 2000. Adenovirus-lacZ (Ad/lacZ) was also produced, and administered with BMP-2 to cell culture. The expression of lacZ was analyzed by X-gal staining. Bone formation was assessed by alkaline phosphatase, von Kossa, and alizarin Red-S staining, and the expression of osteocalcin was determined immunocytochemically. RESULTS: Ligamentum flavum cell cultures with Ad/lacZ showed marker gene expression. BMP-2 induced osteogenesis in ligamentum flavum cells as evidenced by alkaline phosphatase, von Kosa, and alizarin Red-S staining. Also, cell culture with BMP-2 showed strong positivity with osteocalcin by immunocytochemistry. CONCLUSION: BMP-2 more strongly induced the osteogenesis of ligamentum flavum, and also its gene transfer to ligamentum flavum was found to be feasible. These results may open a new era of ligamentum flavum tissue engineering.