壳多糖基质网架复层组织工程皮肤的移植研究

GRAFTING RESEARCH OF TISSUE ENGINEERED ARTIFICIAL RAT SKIN EQUIVALENT ON FULL-THICKNESS WOUNDS

目的 探讨组织工程皮肤动物移植实验的效果。 方法 应用以壳多糖为基质网架构建的组织工程化复层人工皮肤 ,对裸鼠大面积 (直径 2 0 mm)全层皮肤缺损模型进行移植修复。 2 4只 8周龄裸鼠分为组织工程皮肤移植 (AS)组、壳多糖膜覆盖物 (CH)组及对照组 ,术后进行大体观察 ,并在 3、7、14和 2 1天应用组织学、红外热像扫描分析等手段对修复组织进行动态监测。 结果 AS组在移植第 3天 ,组织工程皮肤与自体皮肤能够很好地融合 ,有少量毛细血管长入移植物 ,皮肤移植物颜色与自体皮肤颜色接近 ;随着时间的延长 ,移植物中毛细血管的数量逐渐增多 ,表皮层清晰可见基底层、棘细胞层、颗粒层和角质层 ,角化征象加强 ,有角化物脱落 ;真皮层细胞数量增多 ,网架逐渐降解 ,分泌的细胞外基质成分增多 ;第 14天 ,创面基本愈合 ,修复区皮肤颜色与正常皮肤颜色非常接近 ,瘢痕小 ,无需进行二次植皮。CH组至移植第 14天 ,结痂未完全脱落 ,创面未愈合 ,颜色较 AS组深 ;第 2 1天创面愈合 ,遗留较大瘢痕 ,与正常皮肤区分明显 ,而对照组的结痂脱落 ,创面大而深 ,颜色深红。 结论 以壳多糖为基质网架构建的组织工程化皮肤具有良好的组织相容性 ,可应用于皮肤缺损的移植修复。

Objective To study the grafting effect of tissue engineered artificial rat skin equivalent on full thickness wounds. Methods Full thickness wounds(Φ20mm) were made on the backs of twenty four nude mice which be divided in artificial skin(AS) group, chitosan membrane(CH) group and control group. All wounds were covered with AS, CH and petrolatum gauze , respectively. The wounds were observed daily by infrared ray scanning and histological examination on the 3rd , 7th, 14th, and 21st days. Results The wounds in AS group healed better than those in CH group and control group. The artificial skin achieved a good adherence to wound and there were some crescent regenerative blood vessel appeared in the AS group on the 3rd day of grafting. Then, the epidermal cells in artificial skin proliferated and differentiated to form a new epidermis consisting of stratum basal, stratum spinosum, stratum granulosum, stratum corneum almost like the natural skin. Dermis of the skin consisted of crescent fibroblasts and extracellular matrix secreted by fibroblasts; the chitosan lattice was degraded and replaced by the extracellular matrix. On the 14th day of grafting, the wounds healed. The color of artificial skin grafted was very similar to the natural skin and the formed scar was very small. Conclusion A kind of new reconstructive tissue engineering artificial skin has good histocompatibility and can be transplanted into the full thickness wounds.