Fabrication and in vivo evaluation of an osteoblast-conditioned nano-hydroxyapatite/gelatin composite scaffold for bone tissue regeneration

J Biomed Mater Res A. 2016 Aug;104(8):2001-10. doi: 10.1002/jbm.a.35731. Epub 2016 Apr 19.

Abstract

In this study, the effects of osteoblast-conditioning on mechanical behavior, biocompatibility, biodegradation and osteoinductive properties of a nano-hydroxyapatite/gelatin (HA/GEL) nanocomposite scaffold was investigated. The scaffold was fabricated using the layer solvent casting combined with the freeze-drying and lamination techniques. The scaffolds were conditioned by culture of osteoblasts on their surface and their elimination by a repeated freeze-thawing process. The potential of the osteoblast-conditioned HA/GEL (HA/GEL/OC) scaffold to support cell adhesion and growth and its cytotoxicity was assessed in vitro using rat mesenchymal stem cells. For in vivo studies, the HA/GEL/OC nanocomposite was implanted in the critical size bone defect created on rat calvarium and studied after 7, 30 and 90 days. The results showed that mechanical and in vitro biological properties of the scaffold were not affected by the process of conditioning. However, in vivo studies demonstrated that osteoblast-conditioning enhanced biocompatibility and osteoinductivity and of the nanocomposite scaffold. The osteoblast conditioning also accelerated collagen content during the bone healing. In the experimental group that received the HA/GEL/OC and MSCs, the newly formed bone occupied almost the entire defect (93.4 ± 3.3%) within 3 months. In conclusion, this study indicates that osteoblast-conditioning is a viable strategy for the development of bone tissue engineering scaffolds. © 2016 Wiley Periodicals, Inc. J Biomed Mater Res Part A: 104A: 2001-2010, 2016.

Keywords: bone replacement materials; bone substitutes; tissue engineering.

MeSH terms

  • Animals
  • Bone Regeneration / drug effects*
  • Bone and Bones / drug effects
  • Bone and Bones / pathology
  • Cell Adhesion / drug effects
  • Cell Death / drug effects
  • Cell Line
  • Cell Survival / drug effects
  • Collagen / metabolism
  • Durapatite / pharmacology*
  • Flow Cytometry
  • Freezing
  • Gelatin / pharmacology*
  • Humans
  • L-Lactate Dehydrogenase / metabolism
  • Male
  • Mesenchymal Stem Cells / cytology
  • Mesenchymal Stem Cells / drug effects
  • Nanocomposites / chemistry*
  • Nanocomposites / ultrastructure
  • Osteoblasts / cytology*
  • Osteogenesis / drug effects
  • Rats, Sprague-Dawley
  • Staining and Labeling
  • Tissue Scaffolds / chemistry*

Substances

  • Gelatin
  • Collagen
  • Durapatite
  • L-Lactate Dehydrogenase