Enhancing vaginal reconstruction through 3D bioprinted scaffolds using a novel vECM-GelMA-SF bioink

Abstract Overcoming the low cell survival rates and insufficient neovascularization associated with tissue engineering of the vagina is crucial for advancing the vaginal reconstruction. In this research, we have developed a unique bioink composed of porcine vaginal extracellular matrix (vECM), gelatin methacrylamide (GelMA), and silk fibroin (SF) to facilitate the bioprinting of a vaginal scaffold. The vECM-GelMA-SF bioink effectively replicates the in vivo microenvironment, supporting the in vitro cultivation of 3D bioprinted vaginal scaffolds. It promotes stem cell viability and enhances neovascularization by harnessing the mechanical properties of GelMA/SF and the tissue specificity of vECM. In vivo orthotopic studies have demonstrated that the use of 3D bioprinted vaginal scaffolds significantly improves the functionality of reconstructed vaginas, promoting angiogenesis, rapid epithelialization, muscle regeneration, glycogen secretion, and nerve repair. The reconstructed vaginal tissues in the 3D cell-loaded scaffold group closely resemble natural vaginal tissues. Differential proteomics analysis has provided insights into the genetic functions and biological pathways involved in vaginal reconstruction. Our study successfully optimized the composition of the vECM-GelMA-SF bioink, achieving a balance between biocompatibility and printability. This bioink is suitable for constructing 3D bioprinted vaginal scaffolds of various dimensions, transplantable in situ in animal models with different degrees of vaginal absence. The bioink may find applications in clinical settings, improving the overall effectiveness and safety of in vivo vaginal reconstruction procedures.