Off-the-Shelf Implant to Bridge a Urethral Defect: Multicenter 8-Year Journey From Bench to Bed

Area of Science:

• Biomaterials Engineering
• Regenerative Medicine
• Urology

Background:

• Current urethral reconstruction relies on autologous tissue grafts, which present surgical challenges.
• Cell-based therapies show promise but face high costs and logistical hurdles.

Purpose of the Study:

• To engineer an acellular mesh for urethral reconstruction as an alternative to autologous tissue grafts.
• To evaluate the efficacy of an engineered acellular mesh in animal models for urethral defect repair.

Main Methods:

• Acellular meshes were fabricated from liquid collagen using TissueSpan technology.
• In vitro, mechanical, and bench testing were performed by surgeons.
• The mesh was implanted in urethral defects in rabbits and dogs to assess performance and tissue integration.

Main Results:

• The engineered acellular mesh served as a physical conduit, maintaining urethral patency in animal models.
• The mesh demonstrated absorption within 1-3 months, with spontaneous urothelial coverage and smooth muscle cell migration.
• Successful repair was observed even in a 4 cm long urethral defect in dogs.

Conclusions:

• The acellular mesh shows potential as an off-the-shelf product for substitution urethroplasty.
• Its mechanical and material properties support tissue remodeling and surgical ease.
• Further large-scale clinical trials are necessary to confirm safety and efficacy.