The shortage of skin for grafting continues to be a major problem in the treatment of serious skin injuries. 3D bioprinting provides a new way to solve this problem. However, current 3D printed skin is less effective in treatment of large wounds because of severe shrinkage and scarring. In this study, bionically designed bilayer skin was fabricated using an extrusion-based bioprinter and a gelatin/sodium alginate/gelatin methacrylate hydrogel with excellent physical and biological properties. Full-thickness skin wounds were created in the back of nude mice and treated with bioprinted skin or hydrogel. Bioprinted skin accelerated wound healing, reduced wound contraction and scarring, and facilitated wound skin epithelialization compared with the bioprinted hydrogel or untreated wound. The skin from the wound was collected 28 days after grafting for histology and immunofluorescence analysis. The thickness of the dermis and epidermis of the bioprinted skin was similar to that of nude mice. Microvascular formation in the dermis and dense keratinocytes in the epidermis of the bioprinted skin were observed. This study provides a potential treatment strategy for reducing skin contraction and scar in large skin wounds.

用于移植的皮肤短缺仍然是治疗严重皮肤损伤的主要问题。3D 生物打印为解决这个问题提供了一种新方法。然而，由于严重的收缩和疤痕，目前的 3D 打印皮肤在治疗大伤口方面效果较差。在这项研究中，仿生设计的双层皮肤是使用基于挤出的生物打印机和具有优异物理和生物特性的明胶/海藻酸钠/明胶甲基丙烯酸酯水凝胶制造的。在裸鼠背部制作全层皮肤伤口，并用生物打印皮肤或水凝胶进行处理。与生物打印的水凝胶或未经处理的伤口相比，生物打印的皮肤加速了伤口愈合，减少了伤口收缩和疤痕，并促进了伤口皮肤上皮化。移植后 28 天收集伤口皮肤用于组织学和免疫荧光分析。生物打印皮肤的真皮和表皮厚度与裸鼠相似。观察到真皮中的微血管形成和生物打印皮肤的表皮中致密的角质形成细胞。这项研究为减少大面积皮肤伤口的皮肤收缩和疤痕提供了一种潜在的治疗策略。