Abstract:

BACKGROUND: A variety of dermal substitutes with effective clinical results have now been developed by foreign researchers. But the price is very expensive, so it’s important to develop economical dermal substitutes with high quality.
OBJECTIVE: To observe the histological changes in the dermal substitutes made of China oak silk fibroin after grafting, and to compare with polyvinyl alcohol (PVA) sponge.
METHODS: A full-thickness skin defect at the size of 20 mm × 20 mm was made in the back of clean male SD rats, the skin was cur off into split-thick skin, which were randomized into two groups. Composite transplant of silk fibroin, as a new dermal surrogate, and autologous epidermis was grafted to repair wounds in the experimental group. Composite transplant of polyvinylalcohol sponge, as a new dermal surrogate, and autologous epidermis was grafted to repair wounds in the control group. The tissue biopsies were harvested at 5, 10, 15, 25 post grafting days. The gross appearance and histological changes of the grafts and surrounding tissue were observed. Relative quantitative analysis of transforming growth factor-β1 and proliferating cell nuclear antigen were detected by immunohistochemical method.
RESULTS AND CONCLUSION: The composite skin grafts grew and survived well in the silk fibroin group, while most of the transplants in the sponge group were necrotic and scabbed, even dropped. Immunohistochemical assay showed that the levels of transforming growth factor-β1 and proliferating cell nuclear antigen expression were dramatically higher in silk fibroin group than those in the sponge group during 5 to 25 post grafting days. The revascularization of tissue engineered dermal substitutes made of silk fibroin could begin shortly after grafting, the biocompatibility of silk fibroin is fantastic and it can facilitate the healing of skin wounds.