title: Reconstruct large osteochondral defects of the knee with hIGF-1 gene enhanced Mosaicplasty.
abstract: OBJECTIVE
  To investigate a compound technique including gene therapy, injectable tissue engineering and Mosaicplasty to reconstruct large osteochondral defect.
  
  
  METHODS
  Plasmid vector containing hIGF-1 cDNA was created and transfected into BMSCs in vitro with FuGene6. After gene expression determination, cells were mixed with calcium alginate gel. Osteochondral defects were created on the femoral condyle of goats in a diameter of 6mm. Osteochondral plugs were harvested from the intertrochlea groove and pressed into the recipient sites in a mosaic mode. Gene modified BMSCs-scaffold complex was applied to fill the residual defects. Control groups were also set up. At 4 and 16 weeks, specimens were investigated in gross and under microscopy, electromicroscopy and MRI detection.
  
  
  RESULTS
  hIGF-I gene was expressed effectively with the peak concentration at 34.75 ng/ml. Subchondral bone and cartilage were integrated well in gene enhanced Mosaicplasty group. The reconstructed tissue filled up the gaps between columns, which appeared better than other groups. The regenerated cartilage was integrated with neighbor tightly in regular arrange. Extracellular matrix distributed evenly and deeply stained by alcian blue. Quantitative histologic assessments showed higher score in gene enhanced Mosaicplasty group. Glycosaminoglycan assay revealed no difference between groups involving Mosaicplasty. MRI analysis demonstrated the healing process between the subchondral bone other than control groups.
  
  
  CONCLUSIONS
  hIGF-I gene enhanced tissue engineering can modify the outcome of Mosaicplasty to reconstruct large osteochondral defects in weight-bearing region.
authors.affiliation: Department of Pharmacy, the Affiliated Hospital, School of Medicine, Qingdao University, Qingdao 266003, China.
authors.forename: Ping
authors.initials: P
authors.lastname: Leng
authors.forename: Chang-rong
authors.initials: CR
authors.lastname: Ding
authors.forename: Hai-ning
authors.initials: HN
authors.lastname: Zhang
authors.forename: Ying-zhen
authors.initials: YZ
authors.lastname: Wang
mesh_terms: D000464:Alginates; D000818:Animals; D002358:Cartilage, Articular / Q000473:pathology / Q000601:surgery*; D018076:DNA, Complementary; D005269:Femur / Q000473:pathology / Q000601:surgery; D015316:Genetic Therapy; D020723:Glucuronic Acid; D006041:Goats; D006603:Hexuronic Acids; D007334:Insulin-Like Growth Factor I / Q000627:therapeutic use*; D007719:Knee Joint / Q000473:pathology / Q000601:surgery*; D008297:Male; D033581:Stem Cell Transplantation; D023822:Tissue Engineering
chemical_list: D000464:Alginates; D018076:DNA, Complementary; D006603:Hexuronic Acids; D007334:Insulin-Like Growth Factor I; D020723:Glucuronic Acid