[Experimental study of core binding factor a1 gene-modified rabbit skin fibroblasts enhance bone defect repair].
OBJECTIVE
To investigate bone defect healing by true bone ceramic complex carrying core binding factor a1 (Cbfa1) gene modified rabbit skin fibroblasts.


METHODS
Transfect rabbit skin fibroblasts (RSF) with both eukaryotic expression vector pSG5 which could express Cbfa1 gene and pSG5. After being cultured for 48 h, the transfected RSF were seeded into true bone ceramic (TBC) of 2 cm in length and 4 mm in diameter to construct pSG5-Cbfa1/RSF/TBC complex and pSG5/RSF/TBC complex. Forty-eight bone defect model rabbits were randomized into four groups, each has 6 rabbits (12 radius), due to different treatment. group I: with pSG5-Cbfa1/RSF/TBC complex, group II: with pSG5/RSF/TBC complex, group III: with TBC, Group IV: empty control. After being seeded and cultured for about 24 h the complexes were implanted into 2 cm long bone defects in the middle of bilateral radius of rabbits. The radius were inspected by X-ray and then the specimens were collected at the end of the fourth and twelfth weeks after operation. Then, the specimens were decalcified and histologically investigated with Hematoxylin eosin staining and Masson staining methods. Newly synthesized trabecular bone was inspected by image analysis system and the strength of bone defect area treated with graft-implantation was tested with biomechanical method-three point bending test.


RESULTS
In group I, trabecular bone was actively synthesized to generate a great amount of trabecular bone and osteon. Preliminary union and bone defect healing were completed with good biomechanical characteristics. There were no newly synthesized trabecular in the other three groups, and bone defect healing were not discovered. The amount of newly synthesized trabecular bone and the results of biomechanical testing differed significantly between group I and the other three (P < 0.01). The efficacy of group I was significantly better than that of the other three groups.


CONCLUSIONS
True bone ceramic complex composed with Cbfa1 gene modified rabbit skin fibroblasts can effectively heal bone defect in rabbits.
Xiao
De-chang
DC
Shanghai Institute of Traumatology and Orthopaedics, Orthopaedic Department of Ruijin Hospital, Shanghai Traffic University, Shanghai 200025, China.
Deng
Lian-fu
LF
Yang
Qing-ming
QM
Tan
Yan-bin
YB
Lü
Xue-min
XM
Zhang
Wei
W
Feng
Wei
W
He
Ya-feng
YF
Liang
Jing
J
Zhu
Ya-ping
YP
Qi
Jin
J
Zhou
Qi
Q
Wang
Jun
J
D000818:Animals; D001861:Bone Regeneration; D018786:Bone Substitutes; D016025:Bone Transplantation; D002478:Cells, Cultured; D050659:Core Binding Factor Alpha 1 Subunit / Q000235:genetics*; D004195:Disease Models, Animal; D005347:Fibroblasts / Q000166:cytology / Q000378:metabolism*; D010957:Plasmids / Q000235:genetics; D011817:Rabbits; D011884:Radius / Q000293:injuries / Q000503:physiopathology / Q000601:surgery*; D011897:Random Allocation; D012867:Skin / Q000166:cytology; D023822:Tissue Engineering / Q000379:methods; D014162:Transfection
D018786:Bone Substitutes; D050659:Core Binding Factor Alpha 1 Subunit