异种无细胞真皮基质与薄自体皮复合移植后细胞外基质的变化

Changes of extracellular matrix after transplantation of porcine acellular dermal matrix with thin skin autografts

目的观察异种无细胞真皮基质与薄自体皮复合移植后细胞外基质的动态变化。方法以SD大鼠为动物模型,在其背部造成4 cm×5 cm的全层皮肤缺损。大鼠分为薄自体皮移植组和猪无细胞真皮基质+薄自体皮移植组,分别于移植后1,2,3,4,8,12,16周取标本,检测羟脯氨酸含量、Ⅰ/Ⅲ型前胶原mRNA的表达、透明质酸含量及纤维连接蛋白的变化。结果猪无细胞真皮基质与薄自体皮复合移植后,各时相点羟脯氨酸含量、Ⅰ型前胶原mRNA的表达均低于薄自体皮移植组(P<0.05);Ⅲ型前胶原mRNA的表达与薄自体皮移植组差异无统计学意义(P>0.05);透明质酸含量高于薄自体皮移植组(P<0.05);而纤维连接蛋白的表达在早期高于薄自体皮移植组,后期则低于薄自体皮移植组(P<0.05)。结论猪无细胞真皮基质与薄自体皮复合移植后能够减少胶原合成和Ⅰ型前胶原mRNA的表达,增加皮肤中透明质酸含量,从而减轻瘢痕增生。纤维连接蛋白早期表达增高有利于创面愈合及基底膜的重塑,而后期表达降低有助于减轻瘢痕增生。

Objective To investigate the influence of porcine acellular dermal matrix on extracellular matrix formation after being transplanted onto full-thickness skin defects of SD rats. Methods Full-thickness skin defects （4 cm × 5 cm） were created on the dorsa of SD rats that were divided into two groups, ie, Group A （ implanted with thin skin autografts） and Group B （ implanted with porcine acellular dermal matrix and covered with thin skin autografts）. Skin biopsies were performed at 1,2, 3,4, 8, 12, and 16 weeks after grafting to detect the contents of hyaluronic acid, hydroxyproline, fibronectin and mRNA expressions of procollagens Ⅰ and Ⅲ . Results The content of hydroxyproline in Group B was less thanthat in Group A （P 〈 0.05）. The mRNA expression of procollagen Ⅰ in Group B was less than that in Group A （ P 〈 0. 05）. There was no statistical difference upon the mRNA expression of procollagen Ⅲ in both groups（ P 〉0.05 ）. Content of hyaluronic acid in Group B was higher than that in Group A （P 〈 0.05 ）. The expression of fibronectin in group B was higher than that of group A at the early phase of wound healing but less than that of group A at the late phase（ P 〈0.05 ）. Conclusion Transplantation of porcine acellular dermal matrix with thin skin autografts can decrease the synthesis of collagen and the mRNA expression of procollagen Ⅰ , increase the content of hyaluronic acid, and may alleviate the proliferation of the scar. The high expression of fibronectin at the early phase may facilitate the wound healing and basilar membrane remodeling. Low expression of fibronectin at the late phase may alleviate the proliferation of the scar.