胶原-壳聚糖真皮支架原位诱导修复猪全层皮肤缺损的研究

Study on repair of full-thickness skin defect with collagen-chitosan dermal stent in pigs

目的观察胶原-壳聚糖真皮支架移植于猪皮肤缺损创面后支架的血管化及血管化支架上皮肤移植的成活情况。方法将双层人工皮肤支架移植于10只猪全层皮肤缺损创面，在植入后1、2、3周对真皮支架血管化、创面、血管化支架上皮肤移植愈合情况进行观察；同时用免疫组织化学方法，对CD34阳性信号（新生血管数目）进行检测。结果支架植入后1周支架内可见细胞浸润和少量新生微血管形成；植入后2周，垂直于创面的新生微血管明显增多；植入后3周，大部分支架被血管化。CD34阳性信号在支架植入后3周比植入后2周明显增多，植入后2周比植入后1周明显增多。在支架植入后1、2、3周创面植中厚皮，植皮2周后皮片存活率分别为10％、70％和100％。在支架植入后1周和2周创面植表皮，1周和2周后移植表皮存活良好。结论胶原-壳聚糖真皮支架可以诱导血管长入，明显促进创面愈合。在支架上移植表皮，可较好修复创面，在皮肤移植中有良好的应用前景。

Objective To investigate angiogenesis of collagen-chitosan porous scaffold, and to study survive of skin grafts on the scaffold after bilayer dermal equivalent （BDE） was transplanted on wounds with full thickness skin defects. Methods The full thickness skin defects were made on 10 Bama miniature pigs and the BDE composed of collagen-chitosan porous scaffold and silicone membrane was transplanted on wound. Angiogenesis in dermal equivalent, wound healing, and healing and survive of skin grafts on dermal equivalent were observed in 1, 2, and 3 weeks after the BDE transplantation. At the same time, CD34 positive signals （neo-forming micro-vessels ） were detected by immunohistochemical staining. Results Inflammatory cells and fibroblasts infiltrated into dermal equivalent and a few new micro-vessels had been formed in 1 week after the BDE transplantation; neo-forming micro-vessels perpendicular to wound bed had increased significantly in 2 weeks after the BDE transplantation; neo-forming micro-vessels could be observed in almost all dermal equivalents in 3 weeks after the BDE transplantation. CD34 positive signals （neoforming micro-vessels） in 3 weeks after the BDE transplantation was much more than those in 2 weeks after the BDE transplantation, and CD34 positive signals in 2 weeks after the BDE transplantation was much more than those in 1 week after the BDE transplantation. Survival rate of intermediate split thickness skin graft were 10%, 70% and 100% respectively after the skin grafts had been grafted for 2 weeks on surface of the scaffold which had been transplanted for 1, 2 and 3 weeks. Epidermis which had been grafted on surface of the scaffold for 1 or 2 weeks could perfectly survive after BDE had been transplanted for 1 or 2 weeks. Conclusions Collagen-chitosan porous scaffold plays a very important role in wound healing of full thickness skin defect and can induce fibroblast infiltration and new micro-vessel formation. Epidermis grafted on surface of collagen-chitosan porous scaffold can perfectly repair wounds, and it has brilliant applied prospects in repairing skin defect.