The enhancement of osteogenesis by scaffold based on mineralized recombinant human-like collagen loading with rhBMP-2
ABSTRACT A biomimetic scaffold based on mineralized recombinant collagen, nano-hydroxyapatite/recombinant human-like collagen/poly(lactic
acid) (nHA/RHLC/PLA), was prepared with recombinant human bone morphogenic protein-2 (rhBMP-2) for improving the osteoinductive property
of the scaffold. The nHA/RHLC/PLA scaffolds loaded with 10 µg rhBMP-2 and the unloaded scaffolds were implanted subcutaneously in the rat model.
The osteogenetic capacity of these composites was evaluated by CT scan, ALP activity test and histological observation at
4 and 8 weeks after implantation. The experimental results indicated that the osteogenic capability of the scaffolds loaded
with rhBMP-2 was superior to the unloaded scaffold. It was concluded that rhBMP-2 can enhance the osteoinductive property
of the nHA/RHLC/PLA scaffold and the nHA/RHLC/PLA scaffold loaded with rhBMP-2 have the good potential of being used in bone tissue engineering.
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ABSTRACT: Composite scaffold comprised of hollow hydroxyapatite (HA) and chitosan (designated hHA/CS) was prepared as a delivery vehicle for recombinating human bone morphogenetic protein-2 (rhBMP-2). The in vitro and in vivo biological activities of rhBMP2 released from the composite scaffold were then investigated. The rhBMP-2 was firstly loaded into the hollow HA microspheres, and then the rhBMP2-loaded HA microspheres were further incorporated into the chitosan matrix. The chitosan not only served to bind the HA microspheres together and kept them at the implant site, but also effectively modified the release behavior of rhBMP-2. The in vitro release and bioactivity analysis confirmed that the rhBMP2 could be loaded and released from the composite scaffolds in bioactive form. In addition, the composite scaffolds significantly reduced the initial burst release of rhBMP2, and thus providing prolonged period of time (as long as 60 days) compared with CS scaffolds. In vivo bone regenerative potential of the rhBMP2-loaded composite scaffolds was evaluated in a rabbit radius defect model. The results revealed that the rate of new bone formation in the rhBMP2-loaded hHA/CS group was higher than that in both negative control and rhBMP2-loaded CS group. These observations suggest that the hHA/CS composite scaffold would be effective and feasible as a delivery vehicle for growth factors in bone regeneration and repair.Journal of Materials Science Materials in Medicine 01/2015; 26(1):5336. DOI:10.1007/s10856-014-5336-8 · 2.59 Impact Factor