Cyclo-DfKRG peptide modulates in vitro and in vivo behavior of human osteoprogenitor cells on titanium alloys

Acta Biomater. 2009 Nov;5(9):3581-92. doi: 10.1016/j.actbio.2009.05.018. Epub 2009 May 23.

Abstract

The first aim of the present study was to investigate the capacity of a cyclo-DfKRG-coated hydroxyapatite-titanium alloy (Ti-HA-RGD) to activate in vitro human osteoprogenitor cells adhesion and differentiation. The second purpose was to examine in vivo the role of a autologous cell seeding on cyclo-DfKRG-functionalized materials to provide bone repair after implantation in femoral condyle of rabbits. Our in vitro results have demonstrated that both titanium alloy functionalized with hydroxyapatite (Ti-HA-RGD and Ti-HA) contributed to higher cell adhesion than titanium alloy alone respectively 85 and 55% vs 15% compared to tissue culture polystyrene after one hour of cell seeding. As for differentiation, after 3 days of culture, Ti-HA presented the highest increase of ALP mRNA of all surfaces studied. Ti-HA-RGD showed an intermediate value about half as high as Ti-HA. Moreover after 3 days, both Ti-HA and Ti-HA-RGD surfaces showed the highest increase of cbfa1 mRNA expression. Two weeks following implantation, in vivo findings revealed that percentage of lacunae contact observed with pre-cellularized Ti-HA-RGD samples remains significantly lower than with Ti-HA group (10.5+/-9.6 % vs 33.7+/-11.5 %, P<0.03). Meanwhile, RGD peptide coating had no significant additional effect on the bone implant contact and area. Moreover, histomorphometry analysis revealed that implantation of pre-cellularized RGD coated materials with ROP cells increased significantly peri-implant fibrous area (24+/-11.6% vs 3+/-1.7% for Ti-HA-RGD, P<0.02). RGD coatings demonstrated osteoblastic adhesion, differentiation and in vivo bone regeneration at most equivalent to HA coatings.

Publication types

  • Evaluation Study
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Alloys
  • Animals
  • Cell Adhesion / physiology
  • Cell Differentiation / physiology
  • Cells, Cultured
  • Coated Materials, Biocompatible / chemistry
  • Coated Materials, Biocompatible / metabolism
  • Humans
  • Materials Testing
  • Osteoblasts / cytology
  • Osteoblasts / physiology*
  • Peptides, Cyclic / chemistry
  • Peptides, Cyclic / metabolism*
  • Rabbits
  • Random Allocation
  • Stem Cells / cytology
  • Stem Cells / physiology*
  • Surface Properties
  • Titanium

Substances

  • Alloys
  • Coated Materials, Biocompatible
  • Peptides, Cyclic
  • cyclo-DfKRG
  • Titanium