The repairing of full-thickness skin deficiency and its biological mechanism using decellularized human amniotic membrane as the wound dressing

Human amniotic membrane (HAM) was a biocompatible scaffold with advantages of anti-inflammatory, low antigen, feasibility, tolerance and low cost. In our previous work, HAM was treated to be decellularized using surfactant, lipase and DNAase methods and the efficacy as an implantable biological mesh was verified after decellularization treatment. In this work, we used the previous protocol to decellularize the fresh HAM, and applied it to repair full-thickness skin defects with Sprague-Dawley rats as the test animals. The wound healing progress was followed in the duration of 8 months, and the biological repairing mechanism was explored. From the wound area alteration, white blood cell (WBC) measurements and H&E staining, dHAM was detected to promote the wound healing, comparing with the traditional clinic treatment. Immunohistochemical analyses of the bio-factors involved in the wound healing, vascular endothelial growth factor (VEGF), alpha-smooth muscle actin (α-SMA) and transforming growth factor beta-1 (TGF-β1), exhibited that dHAM enhanced VEGF and α-SMA secretion but reduced TGF-β1 expression at early stage, which alleviated the wound inflammation, promoted the tissue regeneration and relieved the scar formation.