Histologic response of porcine collagen-coated and uncoated polypropylene grafts in a rabbit vagina model

Objective: The purpose of this study was to determine whether the host tissue response in the rabbit vagina differs for 2 synthetic graft materials that are used in pelvic reconstructive surgery. Study Design: One strip of porcine collagen-coated or uncoated polypropylene mesh was implanted adjacent to a sham operative site into the posterior vagina of 10 New Zealand white rabbits and harvested 12 weeks later. Rabbits were assigned randomly to group 1 (coated; n = 5), group 2 (uncoated; n = 5), or group 3 (unoperated; n = 4). Full-thickness sagittal sections of posterior vaginal wall and rectum were scored for inflammation, neovascularization, and fibroblastic proliferation. Results: Erosion of grafts did not occur in any animal. Coated and uncoated meshes induced a mild inflammatory response with minimal fibrosis and good host tissue incorporation within the grafts. Few apoptotic and proliferating cells were seen for both graft types. Conclusion: Both coated and uncoated polypropylene meshes elicit a mild foreign body reaction and minimal fibrotic response without evidence of vaginal epithelial erosion.