A 3D-Bioprinted, Cell-Guiding Hydrogel Patch Promotes Functional Repair of Abdominal Incisions via Anisotropic ECM...

Incisional hernias result from disorganized, mechanically weak scar tissue following abdominal surgery. Current surgical meshes are suboptimal and fail to guide functional regeneration, creating a critical need for new therapeutic approaches. This study introduces an architecture-guided regenerative repair strategy that enhances abdominal incision repair. We developed a Hydrogel-based Architecture-guided Regenerative Patch (HARP) featuring 3D-bioprinted, parallel-aligned filaments that are oriented perpendicular to the incision to provide architectural guidance. The HARP was fabricated from a novel gelatin/dialdehyde cellulose bioink loaded with fibroblasts and TGF-β1 and evaluated in vitro and in a rat abdominal incision model. In vivo, the HARP accelerated healing and yielded a twofold increase in mechanical strength over controls. This resulted from the guided deposition of a dense, anisotropic, type I collagen-rich matrix that resembled native tissue. Our findings support a role for architectural guidance in functional abdominal wall repair, providing a proof of concept for a regenerative repair strategy with the potential to reduce incisional hernia risk.