Inhibiting scar formation in vitro and in vivo by adenovirus-mediated mutant Smad4: a preliminary report.
The best characterized signalling pathway employed by transforming growth factor-beta (TGF-β) is the Smad pathway. We focused on Smad4, because it is essential for the activation of Smad-dependent target genes. We aimed to explore the possibility of inhibiting scar formation after wounding by blocking TGF-β signalling by means of a gene therapy approach using adenovirus-mediated expression of mutant Smad4. The coding sequence of the dominant-negative mutant Smad4ΔM4, which has a deletion in the linker region of Δ275-322, was introduced by homologous recombination into an adenovirus vector to generate the recombinant vector Ad-ΔM4, which encoded Smad4ΔM4. Mouse fibroblast NIH 3T3 cells were transfected with Ad-ΔM4 and cell proliferation, collagen protein production, and the expression of collagen type I and type III mRNA were evaluated in vitro using a cell proliferation test, western blot analysis, and RT-PCR, respectively. Cell proliferation and the expression of collagen type I and type III mRNA and protein were all inhibited by the transfection of Ad-ΔM4. In vivo, Ad-ΔM4 was applied externally to wounds on rats, and histological examination and quantification of the scars were performed to evaluate the curative effect. The transfection of Ad-ΔM4 successfully inhibited scar formation in rat wounds. In conclusion, Ad-ΔM4 can block the TGF-β signalling of mouse wound cells effectively. In addition, gene therapy with Ad-ΔM4 can effectively inhibit wound scarring in rats and may potentially be applied to clinical treatment of scars.
Department of Plastic Surgery, First Affiliated Hospital, College of Medicine, Zhejiang University, Hangzhou, Zhejiang Province, China.
Wei-Qiang
WQ
Tan
Zheng-Jun
ZJ
Gao
Jing-Hong
JH
Xu
Hang-Ping
HP
Yao
D000256:Adenoviridae / Q000235:genetics*; D000818:Animals; D049109:Cell Proliferation; D002921:Cicatrix / Q000473:pathology / Q000503:physiopathology / Q000517:prevention & control*; D024042:Collagen Type I / Q000378:metabolism; D024061:Collagen Type III / Q000378:metabolism; D005347:Fibroblasts / Q000473:pathology; D015316:Genetic Therapy / Q000379:methods*; D066298:In Vitro Techniques; D051379:Mice; D023421:Models, Animal; D009154:Mutation / Q000235:genetics*; D041681:NIH 3T3 Cells; D012333:RNA, Messenger / Q000378:metabolism; D051381:Rats; D017207:Rats, Sprague-Dawley; D015398:Signal Transduction / Q000502:physiology; D051901:Smad4 Protein / Q000235:genetics* / Q000502:physiology; D014162:Transfection; D016212:Transforming Growth Factor beta / Q000037:antagonists & inhibitors / Q000502:physiology; D014945:Wound Healing / Q000502:physiology*
D024042:Collagen Type I; D024061:Collagen Type III; D012333:RNA, Messenger; D051901:Smad4 Protein; C490810:Smad4 protein, mouse; C490811:Smad4 protein, rat; D016212:Transforming Growth Factor beta