Transplanted Bone Morphogenetic Protein/Poly(lactic- co -glycolic Acid) Delayed-release Microcysts Combined with Rat Micromorselized Bone and Collagen for Bone Tissue Engineering

Abstract

This study was designed to optimize the preparation of delayed-release microcysts containing bone morphogenetic protein 2 (BMP-2) combined with poly(lactic-co-glycolic acid) (PLGA) and to investigate their osteogenic properties when combined with rat autologous micromorselized bone and collagen. Rat autologous micromorselized bone, collagen and BMP-2/PLGA delayed-release microcysts were implanted in various combinations into the rat gluteus maximus muscle sack model. The following post-operative measurements were made: general observations of the implant site, histological observations, osteogenesis measurements and alkaline phosphatase activity. Autologous micromorselized bone combined with collagen and BMP-2/PLGA delayed-release microcysts demonstrated significantly superior osteogenic properties than any of the other combinations of these three components. These findings suggest that micromorselized bone combined with collagen and BMP-2/PLGA delayed-release microcysts could reduce the quantity of BMP-2 and autologous bone required for these procedures, making their use feasible in human bone restoration.

Keywords

Bone transplantation Bone tissue engineering Bone morphogenetic protein 2 Growth factors Controlled–release technology Microcyst Y Ji and GP Xu contributed equally to this study.

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