title: Human adipose derived stem cells reduce callus volume upon BMP-2 administration in bone regeneration.
abstract: BACKGROUND
  The demand for new therapeutic approaches to treat bone defects and fractures is increasing in trauma surgery and orthopaedics because the number of patients with degenerative diseases is continuously growing. "Tissue Engineering" offers promising new technologies that combine the three components - cells, growth factors and matrix. Efforts are targeted at improving and accelerating recovery, especially for long bone fractures, and reducing the risk of delayed bone healing or pseudoarthrosis. Adult human adipose-derived stem cells (ASC) can differentiate into osteoblasts in an osteogenic surrounding. Bone morphogenetic protein-2 (BMP-2) accelerates and initiates this differentiation. Fibrin, a matrix that promotes wound healing, is a promising carrier for ASCs and BMP-2.
  
  
  METHODS
  In this study, a 2mm transcortical drill hole in the femur of male rats served as a small non-critical size defect model for fracture simulation. In vivo bone healing was investigated upon administration of the growth factor BMP-2 embedded with ASCs in a locally applied fibrin matrix. Groups with the components alone were also investigated. After 2 and 4 weeks, μCT and histology were performed to determine the bone and callus volume.
  
  
  CONCLUSIONS
  After only a short period of time (2 and 4 weeks), this animal model discloses comparative information about the osteogenetic potential and bone regeneration with little effort (no osteosynthesis necessary). The most significant result found in this model is that the combination of ASCs and BMP-2 in a fibrin matrix significantly reduces callus formation after 2 weeks compared to BMP-2 alone. BMP-2 alone significantly increased callus formation. ASCs embedded alone in the fibrin matrix did not lead to increased bone regeneration.
  
  
  CONCLUSIONS
  Transplantation of ASC modulated the callus induction by BMP-2 to a normal volume.
authors: Ludwig Boltzmann Institute for Experimental and Clinical Traumatology, AUVA Research Center, Austrian Cluster for Tissue Regeneration, Donaueschingenstrasse 13, Vienna, Austria. claudia.keibl@trauma.lbg.ac.at
authors: Claudia
authors: C
authors: Keibl
authors: Alexander
authors: A
authors: Fügl
authors: Gerald
authors: G
authors: Zanoni
authors: Stefan
authors: S
authors: Tangl
authors: Susanne
authors: S
authors: Wolbank
authors: Heinz
authors: H
authors: Redl
authors: Martijn
authors: M
authors: van Griensven
mesh_terms: D000273:Adipose Tissue / Q000166:cytology*; D000818:Animals; D055396:Bone Morphogenetic Protein 2 / Q000008:administration & dosage*; D001861:Bone Regeneration / Q000502:physiology*; D002146:Bony Callus / Q000473:pathology*; D002478:Cells, Cultured; D005269:Femur / Q000293:injuries; D005337:Fibrin / Q000008:administration & dosage; D017102:Fracture Healing / Q000502:physiology*; D008297:Male; D051381:Rats; D017207:Rats, Sprague-Dawley; D033581:Stem Cell Transplantation / Q000379:methods; D013234:Stem Cells / Q000502:physiology*
chemical_list: D055396:Bone Morphogenetic Protein 2; D005337:Fibrin