Injectable chitosan microparticles incorporating bone morphogenetic protein-7 for bone tissue regeneration.
This study investigates the influence of the controlled release of bone morphogenetic protein 7 (BMP-7) from cross-linked chitosan microparticles on pre-osteoblasts (OB-6) in vitro. BMP-7 was incorporated into microparticles by encapsulation during the particle preparation and coating after particle preparation. Chitosan microparticles had an average diameter of 700 µm containing ∼10-15 ng of BMP-7. The release study profile indicates that nearly 98% of the BMP-7 coated on the microparticles was released in a period of 18 days while only 36% of the BMP-7 encapsulated in the microparticles was released in the same time period. Cell attachment study indicated that the BMP-7 coated microparticles have many cells adhered on the microparticles in comparison with microparticles without growth factors on day 10. DNA assay indicated a statistical significant increase (p < 0.05) in the amount of DNA obtained from BMP-7 encapsulated and coated microparticles in comparison with microparticles without any growth factors. A real-time RT-PCR experiment was performed to determine the expression of a few osteoblast specific genes-Dlx5, runx2, osterix, osteopontin, osteocalcin, and bone sialoprotein. The results thus suggest that chitosan microparticles obtained by coacervation method are biocompatible and helps in improving the encapsulation efficiency of BMP-7. Also BMP-7 incorporated in the microparticles is being released in a controlled fashion to support attachment, proliferation and differentiation of pre-osteoblasts, thus acting as a good scaffold for bone tissue regeneration.
Biomedical Engineering Program, The University of Toledo, Toledo, Ohio, 43614-5807.
Venkata P
VP
Mantripragada
Ambalangodage C
AC
Jayasuriya
D000818:Animals; D000943:Antigens, Differentiation / Q000096:biosynthesis; D055419:Bone Morphogenetic Protein 7 / Q000737:chemistry / Q000494:pharmacology; D001861:Bone Regeneration / Q000187:drug effects*; D002448:Cell Adhesion / Q000187:drug effects; D002454:Cell Differentiation / Q000187:drug effects*; D002460:Cell Line; D049109:Cell Proliferation / Q000187:drug effects*; D048271:Chitosan; D003692:Delayed-Action Preparations / Q000737:chemistry / Q000494:pharmacology; D055767:Immobilized Proteins / Q000737:chemistry / Q000494:pharmacology; D008422:Materials Testing; D051379:Mice; D010006:Osteoblasts / Q000166:cytology / Q000378:metabolism*
D000943:Antigens, Differentiation; D055419:Bone Morphogenetic Protein 7; D003692:Delayed-Action Preparations; D055767:Immobilized Proteins; C525820:bmp7 protein, mouse; D048271:Chitosan
BMP-7; chitosan; controlled release; in vitro; microparticles; osteoblasts