Abstract:

BACKGROUND: Bone morphogenetic protein (BMP) is important in bone tissue engineering and it is easily degraded by protainases in the body. According to the related researches, polyethlenepyrolindone (PVP) can effectively make BMP to releases lower and has good biocompatibility with the stent.
OBJECTIVE: To study the effect of the delayed release system of PVP modified nano-hydroxyapatite, then to cultivate it with bone marrow mesenchymal stem cells (BMSCs) that have been induced to osteoblasts to prepare a new delayed release system with good biocompatibility.
METHODS: The samples were divided into three groups: PVP modified BMP combined with nano-hydroxyapatite; unmodified BMP combined with nano-hydroxyapatite; PVP modified BMP combined with spongy bone from SD rat bone marrows. First, the activity of PVP-BMP microsphere was detected by ELISA. Second, after the BMSCs were induced and proliferated to osteoblasts, they were seeded onto the scaffold. The number of cells on the scaffold was counted at different time points (3, 7, 10, 14 days). The cell growth on scaffold was also observed by scanning electron microscope 14 days later.
RESULTS AND CONCLUSION: The expression of BMP was still higher after 14 days in the experimental group. The differentiation of BMSCs to osteoblastic phenotype was demonstrated by the positive staining of collagen type Ⅰ. The cast-off cells from the scaffold in the experimental group were obviously more than those in the control group (P < 0.05). Scanning electron microscope observed that the cell grew better in the experimental group than in the control group. PVP-modified BMP-nanohydroxyapatite delayed release system has good effect, it can cause BMSCs to proliferate and differentiate well.