Biomimetic tubular nanofiber mesh and platelet rich plasma-mediated delivery of BMP-7 for large bone defect regeneration

Cell Tissue Res. 2012 Mar;347(3):603-12. doi: 10.1007/s00441-011-1298-z. Epub 2012 Jan 26.

Abstract

There is a growing need for successful bone tissue engineering strategies and advanced biomaterials that mimic the structure and function of native tissues carry great promise. Successful bone repair approaches may include an osteoconductive scaffold, osteoinductive growth factors, cells with an osteogenic potential and capacity for graft vascularisation. To increase osteoinductivity of biomaterials, the local combination and delivery of growth factors has been developed. In the present study we investigated the osteogenic effects of calcium phosphate (CaP)-coated nanofiber mesh tube-mediated delivery of BMP-7 from a PRP matrix for the regeneration of critical sized segmental bone defects in a small animal model. Bilateral full-thickness diaphyseal segmental defects were created in twelve male Lewis rats and nanofiber mesh tubes were placed around the defect. Defects received either treatment with a CaP-coated nanofiber mesh tube (n = 6), an un-coated nanofiber mesh tube (n=6) a CaP-coated nanofiber mesh tube with PRP (n=6) or a CaP-coated nanofiber mesh tube in combination with 5 μg BMP-7 and PRP (n = 6). After 12 weeks, bone volume and biomechanical properties were evaluated using radiography, microCT, biomechanical testing and histology. The results demonstrated significantly higher biomechanical properties and bone volume for the BMP group compared to the control groups. These results were supported by the histological evaluations, where BMP group showed the highest rate of bone regeneration within the defect. In conclusion, BMP-7 delivery via PRP enhanced functional bone defect regeneration, and together these data support the use of BMP-7 in the treatment of critical sized defects.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Biomechanical Phenomena / drug effects
  • Biomimetic Materials / pharmacology*
  • Bone Morphogenetic Protein 7 / pharmacology*
  • Bone Regeneration / drug effects*
  • Bone and Bones / diagnostic imaging
  • Bone and Bones / drug effects
  • Bone and Bones / pathology*
  • Drug Delivery Systems / methods*
  • Imaging, Three-Dimensional
  • Male
  • Nanofibers / chemistry*
  • Nanofibers / ultrastructure
  • Osseointegration / drug effects
  • Platelet-Rich Plasma / metabolism*
  • Rats
  • Rats, Inbred Lew
  • Tissue Scaffolds / chemistry
  • Torque
  • X-Ray Microtomography

Substances

  • Bone Morphogenetic Protein 7