Optimization of an Affordable and Efficient Skin Allograft Composite with Excellent Biomechanical and Biological Properties Suitable for the Regeneration of Deep Skin Wounds: A Preclinical Study

Deep skin wounds require grafting with a skin substitute for treatment. Despite many attempts in the development of an affordable and efficient skin substitute, the repair of deep skin wounds still remains challenging. In the current study, we present a 3D sponge composite made from human placenta (a disposable organ) and sodium alginate with exceptional properties for skin tissue engineering applications. Toward this goal, different proportions of alginate (Alg) and decellularized placenta scaffold (DPS) were composited and freeze-dried to generate a 3D sponge with the desired biomechanical and biological features. Comprehensive in vitro, in ovo, and in vivo characterizations were performed to assess the morphology, physical structure, mechanical behaviors, angiogenic potential, and wound healing properties of the composites. Through these analyses, the scaffold with optimal proportions of Alg (50%) and DPS (50%) was found to have superior properties. The optimized scaffold (Alg50/DPS50) was applied to the full-thickness wounds created in rats. Our data revealed that the addition of DPS to the Alg solution caused a significant improvement in the mechanical characteristics of the scaffold. Remarkably, the fabricated composite scaffold exhibited mechanical properties similar to those of native skin tissue. When implanted into the full-thickness wounds, the Alg50/DPS50 composite scaffold promoted angiogenesis, re-epithelialization, and granulation tissue formation, as compared to the group without a scaffold. Overall, our findings underscore the potential value of this hybrid scaffold for enhancing skin wound healing and suggest an Alg50/DPS50 composite for clinical investigations.