Turkey ovarian tissue transplantation: effects of surgical technique on graft attachment and immunological status of the grafts, 6 days post-surgery

Authors: HALL, GEORGE - University Of Guelph; Long, Julie; SUSTA, L - University Of Guelph; WOOD, BENJAMIN - Hybrid Turkeys; BEDECARRATS, GREGOY - University Of Guelph

Submitted to: Cell and Tissue Banking
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 11/22/2021
Publication Date: 3/15/2022
Citation: Hall, G.B., Long, J.A., Susta, L., Wood, B.A., Bedecarrats, G.Y. 2022. Turkey ovarian tissue transplantation: effects of surgical technique on graft attachment and immunological status of the grafts, 6 days post-surgery. Cell and Tissue Banking. 101(3):101648. https://doi.org/10.1016/j.psj.2021.101648.
DOI: https://doi.org/10.1016/j.psj.2021.101648

Interpretive Summary: Biobanking of reproductive organs is one method of preserving the genetics of valuable animals and important genetic lines. In this process, ovaries from young donor birds can be frozen, stored at low temperatures for extended periods of time, thawed to body temperature, and surgically transplanted into new recipient birds. ARS scientists, in collaboration with scientists from the University of Guelph, have been developing and refining methods for biobanking ovarian tissue from turkeys. One challenge of applying this method to turkeys involves the surgical technique. In this paper, we confirmed that the recipient ovary can be completely removed, and that placement of the air sac membrane does not affect the rate of attachment of the transplanted ovary. This surgical procedure resulted in 91% of the donor ovaries attaching, and is an important step in developing biobanking methods for turkeys.

Technical Abstract: Background: Biobanked poultry ovarian tissue can be revived by transplanting it 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 behind 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 certain portions (33% to 100%) of recipient ovarian tissue and determined that 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 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 recipient 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.