Preliminary outcomes and transcriptomic analysis of xenogeneic human-derived acellular dermal matrix patches for complex ureteral stricture reconstruction in a porcine model.

Background: Complex upper and middle ureteral strictures, particularly segmental defects longer than 2 cm, are difficult to repair with tension-free end-to-end anastomosis and often require autologous grafts. This pilot study evaluated human-derived acellular dermal matrix (ADM-H) as a xenogeneic scaffold for ureteral reconstruction in a porcine model. Methods: Three female Bama miniature pigs underwent unilateral thulium laser-induced ureteral stricture modeling. Because the exact length of the obliterated stenotic segment produced by laser cauterization was not fully controllable, a standardized 2-cm transection criterion was used during reconstruction. The stenotic segment was resected and replaced with a rolled ADM-H tubular scaffold over a double-J stent. Imaging, ureteroscopy, gross examination, histology, and RNA sequencing were performed at day 45. Results: All animals completed the observation period. At day 45, ADM-H-reconstructed segments showed early luminal patency on antegrade urography and ureteroscopy, with continuous urothelial coverage, organized collagen deposition, neovascularization, and early smooth muscle remodeling. Transcriptomic analysis showed enrichment of pathways related to epithelial repair, cell adhesion, and extracellular matrix remodeling. Conclusions: These preliminary findings support the technical feasibility of ADM-H ureteroplasty as a potential substitute for autologous grafts in segmental ureteral reconstruction. Because this study included only three animals, a short stent-free follow-up interval, no active surgical control group, and limited functional testing, longer-term controlled studies are required before efficacy can be established.