title: Implantation of canine umbilical cord blood-derived mesenchymal stem cells mixed with beta-tricalcium phosphate enhances osteogenesis in bone defect model dogs.
abstract: This study was performed to evaluate the osteogenic effect of allogenic canine umbilical cord blood-derived mesenchymal stem cells (UCB-MSCs) mixed with beta-tricalcium phosphate (beta-TCP) in orthotopic implantation. Seven hundred milligrams of beta-TCP mixed with 1 x 10(6) UCB-MSCs diluted with 0.5 ml of saline (group CM) and mixed with the same volume of saline as control (group C) were implanted into a 1.5 cm diaphyseal defect and wrapped with PLGC membrane in the radius of Beagle dogs. Radiographs of the antebrachium were made after surgery. The implants were harvested 12 weeks after implantation and specimens were stained with H&E, toluidine blue and Villanueva-Goldner stains for histological examination and histomorphometric analysis of new bone formation. Additionally, UCB-MSCs were applied to a dog with non-union fracture. Radiographically, continuity between implant and host bone was evident at only one of six interfaces in group C by 12 weeks, but in three of six interfaces in group CM. Radiolucency was found only near the bone end in group C at 12 weeks after implantation, but in the entire graft in group CM. Histologically, bone formation was observed around beta-TCP in longitudinal sections of implant in both groups. Histomorphometric analysis revealed significantly increased new bone formation in group CM at 12 weeks after implantation (p < 0.05). When applied to the non-union fracture, fracture healing was identified by 6 weeks after injection of UCB-MSCs. The present study indicates that a mixture of UCB-MSCs and beta-TCP is a promising osteogenic material for repairing bone defects.
authors.affiliation: Department of Veterinary Surgery, College of Veterinary Medicine, Seoul National University, Seoul 151-742, Korea.
authors.forename: Byung Jun
authors.initials: BJ
authors.lastname: Jang
authors.forename: Ye Eun
authors.initials: YE
authors.lastname: Byeon
authors.forename: Ji Hey
authors.initials: JH
authors.lastname: Lim
authors.forename: Hak Hyun
authors.initials: HH
authors.lastname: Ryu
authors.forename: Wan Hee
authors.initials: WH
authors.lastname: Kim
authors.forename: Yoshihisa
authors.initials: Y
authors.lastname: Koyama
authors.forename: Masanori
authors.initials: M
authors.lastname: Kikuchi
authors.forename: Kyung Sun
authors.initials: KS
authors.lastname: Kang
authors.forename: Oh Kyeong
authors.initials: OK
authors.lastname: Kweon
mesh_terms: D000818:Animals; D001672:Biocompatible Materials / Q000378:metabolism / Q000627:therapeutic use; D018786:Bone Substitutes / Q000627:therapeutic use*; D002130:Calcium Phosphates / Q000627:therapeutic use*; D004285:Dogs; D005312:Fetal Blood / Q000166:cytology*; D005592:Fracture Fixation / Q000379:methods / Q000662:veterinary; D059630:Mesenchymal Stem Cells / Q000502:physiology*; D010012:Osteogenesis / Q000502:physiology*; D023822:Tissue Engineering / Q000379:methods; D014945:Wound Healing / Q000502:physiology
chemical_list: D001672:Biocompatible Materials; D018786:Bone Substitutes; D002130:Calcium Phosphates; C485817:beta-tricalcium phosphate