Effects of preparation methods on the bone formation potential of apatite-coated chitosan microspheres

• Published in: Journal of biomaterials science. Polymer ed. Vol. 25; no. 18; pp. 2080 - 2093
• Main Authors: Xu, Fei, Ding, Huifen, Song, Fangfang, Wang, Jiawei
• Format: Journal Article
• Language: English
• Published: England Taylor & Francis 12.12.2014
• Subjects: Animals; Apatites - chemistry; Biomedical materials; BMSCs; Bone Marrow Cells - cytology; bone regeneration; Bone Regeneration - drug effects; Bones; Cell Adhesion - drug effects; Cell Differentiation - drug effects; Cell Proliferation - drug effects; Chemical Phenomena; Chitosan; Chitosan - chemistry; chitosan microspheres; Coated Materials, Biocompatible - chemistry; Coated Materials, Biocompatible - pharmacology; Construction; In vivo testing; In vivo tests; Male; Mesenchymal Stem Cell Transplantation; Mesenchymal Stromal Cells - cytology; Mesenchymal Stromal Cells - drug effects; Microspheres; Osteogenesis - drug effects; preparation methods; Rats; Rats, Wistar; Skull - surgery; Surgical implants; preparation methods; chitosan microspheres; bone regeneration; BMSCs
• ISSN: 0920-5063; 1568-5624
• DOI: 10.1080/09205063.2014.970604

To investigate the effects of preparation methods on the bone formation potential of apatite-coated chitosan microspheres, coacervate precipitation method and emulsion cross-linking method were chosen to prepare chitosan microspheres, and then apatite coatings were deposited using simulated body fluid. Rat bone marrow-derived mesenchymal stem cells (BMSCs) were seeded on these microspheres. Cell adhesion, proliferation, and differentiation potential were monitored. For in vivo analysis, some cell/microsphere constructs were implanted in the subcutaneous pockets of male Wistar rats. After 3, 6, 12 weeks, the samples were retrieved and stained with hematoxylin and eosin (HE). Some cell/microsphere constructs were implanted in the calvarial defects of rats. Micro-CT and HE analysis were performed to analyze the new bone formation. It was found that BMSCs on apatite-coated emulsion cross-linked microspheres (EM1) exhibited better proliferation and differentiation than cells on apatite-coated coacervate-precipitated microspheres. The in vivo results showed that no bone was observed in ectopic areas. While in calvarial defects, both histological slices and Micro-CT images demonstrated that a substantial amount of new bone was formed in the EM1/BMSCs construct. These data suggest that preparation methods do exert great influence on the in vitro cell behaviors and in vivo orthotopic bone regeneration of apatite-coated chitosan microspheres. Appropriate method should be considered when preparing chitosan microspheres for bone tissue engineering scaffold.