Acute and chronic wounds affect millions of people around the world, imposing a growing financial burden on patients and hospitals. Despite the application of current wound management strategies, the physiological healing process is disrupted in many cases, resulting in impaired wound healing. Therefore, more efficient and easy-to-use treatment modalities are needed. In this study, we demonstrate the benefit of in vivo printed, growth factor-eluting adhesive scaffolds for the treatment of full-thickness wounds in a porcine model. A custom-made handheld printer is implemented to finely print gelatin-methacryloyl (GelMA) hydrogel containing vascular endothelial growth factor (VEGF) into the wounds. In vitro and in vivo results show that the in situ GelMA crosslinking induces a strong scaffold adhesion and enables printing on curved surfaces of wet tissues, without the need for any sutures. The scaffold is further shown to offer a sustained release of VEGF, enhancing the migration of endothelial cells in vitro. Histological analyses demonstrate that the administration of the VEGF-eluting GelMA scaffolds that remain adherent to the wound bed significantly improves the quality of healing in porcine wounds. The introduced in vivo printing strategy for wound healing applications is translational and convenient to use in any place, such as an operating room, and does not require expensive bioprinters or imaging modalities.

急性和慢性伤口影响着全世界数百万人，给患者和医院带来了越来越大的经济负担。尽管应用了当前的伤口处理策略，但在许多情况下，生理愈合过程被破坏，导致伤口愈合受损。因此，需要更有效且易于使用的治疗方式。在这项研究中，我们展示了体内打印的生长因子洗脱粘合支架在猪模型中治疗全层伤口的益处。采用定制的手持式打印机将含有血管内皮生长因子（VEGF）的明胶甲基丙烯酰（GelMA）水凝胶精细地打印到伤口中。体外和体内结果表明，原位GelMA 交联可产生强大的支架粘附力，并能够在湿组织的弯曲表面上进行打印，无需任何缝合。该支架还被证明能够持续释放 VEGF，从而增强内皮细胞的体外迁移。组织学分析表明，施用仍粘附在伤口床上的 VEGF 洗脱 GelMA 支架可显着提高猪伤口的愈合质量。引入的用于伤口愈合应用的体内打印策略是可转化的并且方便在任何地方使用，例如手术室，并且不需要昂贵的生物打印机或成像模式。