Turkey Ovarian Tissue Transplantation: Effects of Surgical Technique on Graft Attachment and Immunological Status of the Grafts 6 Days Post-surgery

Abstract

Background: Biobanked poultry ovaries can be revived via transplantation, into a recipient female, which upon maturity will produce donor-derived progeny. Previously, a large portion of these recipients also produced recipient-derived progeny, making them gonadal chimeras. These were potentially created when portions of the recipient’s ovary were inadvertently left behind. Completely removing the recipient ovary would solve this problem, however, leaving a portion of the recipient’s ovary may have inadvertently increased the transplant attachment rate by providing a damaged area for the transplant to attach too. To test this hypothesis in the turkey, we removed various portions (33% to 100%) of recipient ovarian tissue and determined the transplant attachment rate. Furthermore, the use of the abdominal air sac membrane as an additional anchoring point was tested. Finally, the immunological status of the grafts was evaluated by analyzing the presences of CD3 and MUM-1 (T and B cell markers), 6 days post-surgery.Results: The overall attachment rate of transplants was 91% (32/35), while the average size of the transplants was 4.2 ± 0.6 mm2. There was no difference (P > 0.05) in the attachment rates, or transplant size between groups with varying amounts of recipent tissue removed, or by using the abdominal air sac membrane as an anchor. However, all transplants were infiltrated by large numbers of T and B cells. This was shown by a high (P ≤ 0.001) percentage of CD3-positive immunostained cytoplasmic area (49.78 ± 3.90%) in transplants compared to remnant recipient tissue (0.30 ± 0.10%), as well as a high (P ≤ 0.001) percentage of MUM-1-positive immunostained nuclear area (9.85 ± 1.95%) in transplants over remnant recipient tissues (0.39 ± 0.12%).Conclusions: This study showed that neither the portion of the recipient ovary left behind nor the use of the abdominal air sac membrane affected the rate of attachment or the amount of donor tissue that attached. Thus, we recommend removing the entire recipient ovary to prevent gonadal chimeras. The high levels of lymphocytes within the grafts indicate possible tissue rejection, which could be overcome via immunosuppression with or without histocompatibility matching between donors and recipients.