Allogeneic abdominal non-vascularized rectus fascia transplantation without immunosuppression equals syngeneic transplantation in a rabbit model at short-term follow-up

Transpl Immunol. 2024 Dec:87:102138. doi: 10.1016/j.trim.2024.102138. Epub 2024 Oct 21.

Abstract

Complex abdominal wall repair remains a major surgical challenge. In transplant patients, non-vascularized rectus fascia (NVRF) is successfully used to bridge the defect. To extrapolate this to non-transplant patients, we developed a rabbit model of NVRF-transplantation without immunosuppression comparing syngeneic versus allogeneic transplants. Short-term outcome (4 weeks) was evaluated macroscopically (ingrowth, seroma/hematoma, herniation, and infection), histologically at the graft interface and center (inflammation, neovascularization, and collagen deposition) and by mechanical testing. In both groups a similar macroscopic ingrowth of the NVRF was observed. In the syn-group, one seroma and one hematoma was seen. Two small herniations were detected at the suture line in the allo-group. No surgical site infections were observed. Histologically, graft neovascularization was observed in all animals. Infiltration of T-lymphocytes was seen at the graft interface in both groups, but more in the allo-group (p < 0.0001). Deposition of collagen was not different between groups. Macrophages were present in both groups around sutures and in the center more abundantly in the allo-group (p = 0.0001). Graft stiffness and strength were similar for both groups. With this model, we showed that allogeneic transplantation without immunosuppression results in favorable short-term inflammatory and mechanical outcomes. Long-term experiments are needed to further evaluate the effect on graft integration and hernia development.

Keywords: Abdominal wall; Hernia; Neovascularization - integration; Non-vascularized rectus fascia transplantation; Rabbit model.

MeSH terms

  • Abdominal Wall / pathology
  • Abdominal Wall / surgery
  • Animals
  • Collagen
  • Fascia / transplantation
  • Follow-Up Studies
  • Humans
  • Immunosuppression Therapy
  • Macrophages / immunology
  • Male
  • Rabbits
  • Rectus Abdominis / transplantation
  • T-Lymphocytes / immunology
  • Transplantation, Homologous*
  • Transplantation, Isogeneic

Substances

  • Collagen