The mechanism and role of autologous peritoneum transplantation to enterocystoplasty in porcine model

Abstract

Objective: To explore the pathological mechanism and role of autologous peritoneum transplantation onenterocystoplasty in porcine model. Methods: Randomly, four experimental female swine were chosen, and each of their body weight was 28-33 kg. By intravenous anesthesia, the transplantation of autologous peritoneum for bladder reconstruction operation was carried out (to transplant the peritoneum onto an ileum segment of which the mucosa and submucosa had been removed. These flaps were used to mend and augment the bladder by suturing the edge of detective bladders). After removal of ureteral catheters and balloon catheter at day 5 respectively, their voiding behaviors were monitored, and respectively 2 swine were euthanized at week 3/6 for routine pathology, immunohistochemistry, and electron microscopic examinations. Results: Four swine underwent reconstruction, but none died for complications such as peritonitis, ileus and urinary fistula. The length of ileum was 35 cm, and the area of peritoneum was 15 cm×10 cm. Voiding behaviorsof the swine were normal, with clear urine after removal of their catheters. At autopsy, reconstructed bladders were healthy. Pathological examination showed the neobladder had been covered by continuous urothelium while the peritoneum disappeared without ileal mucosa regrowth or residual. Scanning electron microscope showed that the transitional cells of neobladder of swine were complete and orderly, and urothelium around suture border was continuous withoutmalposition. Conclusions: In porcine model, autologous peritoneal transplantation witnessed no immune rejection response for itself, which was replaced by crawling transitional epithelium around anastomosis, rather than by metaplasia.