[Repairing rabbit orbital defects with human BMP-2 gene modified bone marrow stromal cells and coral].
OBJECTIVE
To investigate the efficacy of tissue-engineered bone (human BMP-2 genetic modified BMSC combined with coral) in healing the segmental orbital defect in rabbits.


METHODS
Rabbit BMSC were isolated and cultured in vitro, and cells of passage 2 were infected with adenovirus-mediated transfection of human BMP-2 gene (150 pfu/cell). After infection, the expression of BMP-2 was determined by RT-PCR and Western blot analysis, and cell proliferation and osteogenic differentiation were observed by flow cytometry, ALP and Alizarin red staining. A 12 mm bone defect in the infraorbital rim was induced by surgery in both orbits of 24 New Zealand white rabbits. The defects were repaired with modified tissue-engineered bone constructed with coral plus BMP-2 transfected BMSC (Group A, n = 12), constructed by coral plus non-transfected BMSC (Group B, n = 12) and grafts of coral alone (Group C, n = 12), with untreated group (Group D, n = 12) served as control. The osteogenesis of bone defect was monitored by gross observation, micro-CT measurement, histological and histomorphologic analysis at 4, 8, and 16 weeks after the implantation.


RESULTS
After transfection, the BMP-2 expression was confirmed by RT-PCR and western blot, and the osteogenesis activity of BMSC could be obviously enhanced. The 12 mm segmental defect of rabbit orbit couldn't heal alone. Gross observation and micro-CT demonstrated well the bony-union in experimental group, with higher bone mineral density and more bone volume than other control groups (F = ll.46, F = 7180.97; P < 0.05).


CONCLUSIONS
This study demonstrated that the rabbit orbital defect could be successfully repaired by tissue-engineered bone constructed with human BMP-2 gene modified BMSC and coral.
Fan
Xian-Qun
XQ
Department of Ophthalmology, Ninth People's Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai 200011, China. fanxq@sh163.net
Xiao
Cai-Wen
CW
Zhou
Hui-Fang
HF
Bi
Xiao-Ping
XP
Shi
Wo-Dong
WD
D000818:Animals; D001854:Bone Marrow Cells / Q000166:cytology; D055396:Bone Morphogenetic Protein 2 / Q000235:genetics*; D001861:Bone Regeneration; D018786:Bone Substitutes; D005822:Genetic Vectors; D059630:Mesenchymal Stem Cells / Q000166:cytology; D009915:Orbit / Q000293:injuries*; D011817:Rabbits; D023822:Tissue Engineering / Q000379:methods*; D014162:Transfection
C525718:BMP2 protein, human; D055396:Bone Morphogenetic Protein 2; D018786:Bone Substitutes