title: An ectopic study of apatite-coated silk fibroin scaffolds seeded with AdBMP-2-modified canine bMSCs.
abstract: The present study was undertaken to evaluate ectopic new bone formation effects of apatite-coated silk fibroin scaffolds (mSS) seeded with adenovirus-mediated bone morphogenic protein-2 gene (AdBMP-2) transduced canine bone marrow stromal cells (bMSCs) in nude mice. In this study, bMSCs  derived from canine were cultured and transduced with AdBMP-2 adenovirus-mediated enhanced green fluorescent protein gene (AdEGFP) in vitro. Osteogenic differentiation of bMSCs was determined by alkaline phosphatase (ALP) activity analysis, and the transcript levels for BMP-2, osteopontin  (OPN), osteocalcin (OCN) and bone sialoprotein (BSP) genes via real-time quantitative PCR (RT-qPCR) analysis. The ectopic bone formation effects of mSS seeded with AdBMP-2-modified bMSCs were evaluated through histological and histomorphological analysis 4, 8 and 12 weeks post-operation  in nude mice. ALP activity was statistically increased in the AdBMP-2 group, when compared with control groups. The mRNA expression of BMP-2, OPN, OCN and BSP was also statistically up-regulated 6 and 9 days after AdBMP-2 transduction. Significantly higher bone volume was achieved in AdBMP-2-transduced  bMSCs/mSS constructs than that of AdEGFP-transduced bMSCs/mSS or bMSCs/mSS groups at 4, 8 and 12 weeks (P < 0.01). These results demonstrated that mSS seeded with AdBMP-2-transduced canine bMSCs can promote ectopic new bone formation and maturation in nude mice, suggesting the potential  of this silk-scaffold-based tissue-engineered bone for further bone regeneration studies in canine models.
authors.affiliation: Department of Prosthodontics, College of Stomatology, Ninth People's Hospital, School of Medicine, Shanghai Jiao Tong University, Shanghai Key Laboratory of Stomatology, Shanghai 200011, P. R. China.
authors.forename: Kaige
authors.initials: K
authors.lastname: Lü
authors.forename: Ling
authors.initials: L
authors.lastname: Xu
authors.forename: Lunguo
authors.initials: L
authors.lastname: Xia
authors.forename: Yilin
authors.initials: Y
authors.lastname: Zhang
authors.forename: Xiuli
authors.initials: X
authors.lastname: Zhang
authors.forename: David L
authors.initials: DL
authors.lastname: Kaplan
authors.forename: Xinquan
authors.initials: X
authors.lastname: Jiang
authors.forename: Fuqiang
authors.initials: F
authors.lastname: Zhang
mesh_terms: D000256:Adenoviridae / Q000235:genetics; D000469:Alkaline Phosphatase / Q000378:metabolism; D000818:Animals; D001031:Apatites / Q000737:chemistry*; D015415:Biomarkers / Q000378:metabolism; D001854:Bone Marrow Cells / Q000166:cytology; D055396:Bone Morphogenetic Protein 2 / Q000235:genetics*; D001861:Bone Regeneration / Q000187:drug effects; D002448:Cell Adhesion / Q000187:drug effects; D020099:Coated Materials, Biocompatible / Q000737:chemistry / Q000494:pharmacology*; D004285:Dogs; D005349:Fibroins / Q000737:chemistry*; D005786:Gene Expression Regulation / Q000187:drug effects; D008297:Male; D051379:Mice; D010012:Osteogenesis / Q000187:drug effects*; D017154:Stromal Cells / Q000166:cytology / Q000187:drug effects* / Q000378:metabolism; D054457:Tissue Scaffolds / Q000737:chemistry*; D014161:Transduction, Genetic
chemical_list: D001031:Apatites; D015415:Biomarkers; D055396:Bone Morphogenetic Protein 2; D020099:Coated Materials, Biocompatible; D005349:Fibroins; D000469:Alkaline Phosphatase