title: A novel BMP2-coprecipitated, layer-by-layer assembled biomimetic calcium phosphate particle: a biodegradable and highly efficient osteoinducer.
abstract: OBJECTIVE
  To repair large-size bone defects, most bone-defect-filling materials in clinic need to obtain osteoinductivity either by mixing them with particulate autologous bone or adsorbing bone morphogenetic protein 2 (BMP2). However, both approaches encounter various limitations. In this study, we hypothesized that our novel particles of biomimetic BMP2-coprecipitated calcium phosphate (BMP2-cop.BioCaP) could serve as an independent and biodegradable osteoinducer to induce bone formation efficiently for these bone-defect-filling materials, for example, deproteinized bovine bone (DBB).
  
  
  METHODS
  We alternately layer-by-layer assembled amorphous and crystalline CaP triply to enable a "bamboo-like" growth of the particles. We functionalized BioCaP by coprecipitating BMP2 into the most outer layer of BioCaP. We monitored the degradation, osteoinductivity, and foreign-body reaction of either BMP2-cop.BioCaP or its combination with DBB in an ectopic site in rats.
  
  
  RESULTS
  After 5 weeks, the BMP2-cop.BioCaP significantly induced new bone formation not only alone but also when mixed with DBB. Its osteoinductive efficiency was 10-fold higher than the adsorbed BMP2. Furthermore, BMP2-cop.BioCaP also reduced significantly the host foreign-body reaction to DBB in comparison with the adsorbed BMP2. After a 5-week implantation, more than 90% of BMP2-cop.BioCaP degraded.
  
  
  CONCLUSIONS
  These findings indicate a promising clinical potential for BMP2-cop.BioCaP in the repair of large-size bone defects.
authors: Department of Oral Implantology and Prosthetic Dentistry, Academic Centre for Dentistry Amsterdam (ACTA), Research Institute MOVE, VU University, University of Amsterdam, Amsterdam, The Netherlands; School of Stomatology/Dental Clinic, Zhejiang Chinese Medical University, Hangzhou, China.
authors: Yuanna
authors: Y
authors: Zheng
authors: Gang
authors: G
authors: Wu
authors: Tie
authors: T
authors: Liu
authors: Yi
authors: Y
authors: Liu
authors: Daniel
authors: D
authors: Wismeijer
authors: Yuelian
authors: Y
authors: Liu
mesh_terms: D000818:Animals; D032701:Biomimetics; D055396:Bone Morphogenetic Protein 2 / Q000008:administration & dosage*; D002130:Calcium Phosphates / Q000737:chemistry*; D008297:Male; D010012:Osteogenesis; D051381:Rats; D017208:Rats, Wistar
chemical_list: D055396:Bone Morphogenetic Protein 2; D002130:Calcium Phosphates; C020243:calcium phosphate
keywords: biomimetic; bone morphogenetic protein; bone regeneration; calcium phosphate; layer-by-layer; osteoinducer