title: Effects of preparation methods on the bone formation potential of apatite-coated chitosan microspheres.
abstract: 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.
authors.affiliation: a Hubei-MOST KLOS & KLOBM, School and Hospital of Stomatology, Wuhan University , Wuhan 430079 , P.R. China.
authors.forename: Fei
authors.initials: F
authors.lastname: Xu
authors.forename: Huifen
authors.initials: H
authors.lastname: Ding
authors.forename: Fangfang
authors.initials: F
authors.lastname: Song
authors.forename: Jiawei
authors.initials: J
authors.lastname: Wang
mesh_terms: D000818:Animals; D001031:Apatites / Q000737:chemistry*; D001854:Bone Marrow Cells / Q000166:cytology; D001861:Bone Regeneration / Q000187:drug effects; D002448:Cell Adhesion / Q000187:drug effects; D002454:Cell Differentiation / Q000187:drug effects; D049109:Cell Proliferation / Q000187:drug effects; D055598:Chemical Phenomena; D048271:Chitosan / Q000737:chemistry*; D020099:Coated Materials, Biocompatible / Q000737:chemistry* / Q000494:pharmacology*; D008297:Male; D045164:Mesenchymal Stem Cell Transplantation; D059630:Mesenchymal Stem Cells / Q000166:cytology / Q000187:drug effects; D008863:Microspheres; D010012:Osteogenesis / Q000187:drug effects*; D051381:Rats; D017208:Rats, Wistar; D012886:Skull / Q000601:surgery
chemical_list: D001031:Apatites; D020099:Coated Materials, Biocompatible; D048271:Chitosan
keywords: BMSCs; bone regeneration; chitosan microspheres; preparation methods