title: Studies on the microspheres comprised of reconstituted collagen and hydroxyapatite.
abstract: Microspheres comprised of hydroxyapatite particles, dispersed in reconstituted fibrous collagen, were prepared and characterized. The hydroxyapatite particles distributed evenly throughout the collagen matrix of the microsphere. Diameters of the reconstituted collagen fibers ranged from 30 to 90 nm, and exhibited a regular banding pattern with cross-striation of 50-60 nm under transmission electron microscope, suggesting that the reconstitution of collagen was not hindered by the hydroxyapatite particulates. When osteoblast cells isolated from newborn rat calvaria were seeded and cultured on the microspheres, the cell density increased from 2x10(4) to 3.2x10(4)cells/cm(2) in 8 days. Von Kossa staining exhibited spotty accumulation of mineral deposits on microspheres indicating matrix mineralization of the cultured cells. Analyses by electron microscopy and confocal microscopy showed that the osteoblast cells spread and attached to the microsphere via focal adhesion, while F-actin and DNA staining demonstrated the presence of stress fibers; moreover, mitotic cells could be observed. Together, these results indicate that osteoblast cells are capable of proliferating, differentiating and mineralizing in the matrix of the microspheres, and suggest that the microspheric composite is a potential grafting material for future clinical applications.
authors: Institute of Biomedical Engineering, National Yang-Ming University, 112, Taipei, Taiwan
authors: Ta-Jen
authors: TJ
authors: Wu
authors: Hsiu-Hsuan
authors: HH
authors: Huang
authors: Cheng-Wen
authors: CW
authors: Lan
authors: Chi-Hung
authors: CH
authors: Lin
authors: Fu-Yin
authors: FY
authors: Hsu
authors: Yng-Jiin
authors: YJ
authors: Wang
mesh_terms: D000818:Animals; D000831:Animals, Newborn; D018786:Bone Substitutes / Q000138:chemical synthesis / Q000737:chemistry*; D002113:Calcification, Physiologic / Q000502:physiology; D002448:Cell Adhesion / Q000502:physiology; D002454:Cell Differentiation / Q000502:physiology; D002455:Cell Division / Q000502:physiology; D002470:Cell Survival / Q000502:physiology; D002478:Cells, Cultured; D003094:Collagen / Q000737:chemistry*; D017886:Durapatite / Q000737:chemistry*; D008422:Materials Testing; D008863:Microspheres; D043942:Nanotubes / Q000737:chemistry* / Q000648:ultrastructure*; D010006:Osteoblasts / Q000166:cytology / Q000502:physiology* / Q000648:ultrastructure*; D010316:Particle Size; D051381:Rats; D017207:Rats, Sprague-Dawley; D023822:Tissue Engineering / Q000379:methods*
chemical_list: D018786:Bone Substitutes; D003094:Collagen; D017886:Durapatite