Current Status of Pig-to-NHP Xenotransplantation Research in Korea.

Background: Xenotransplantation has the potential to mitigate the shortage of transplantable organs in Korea. However, its clinical application is yet to be established. Preclinical studies using non-human primates (NHPs) are required, as these animal models may yield excellent results. Therefore, we aimed to investigate the progress in pig-to-NHP xenotransplantation research in Korea and identify alternative approaches for the clinical application of human xenotransplantation.

Methods: We investigated the use of transgenic pigs developed by Optipharm (8; QKO+CD39+CD55+CD46+TBM) and the National Institute of Animal Science (4; GTKO, CMAH, HO1, and CD47) for xenotransplantation in Korea. We further analyzed the outcomes of 100 pig-to-NHP xenotransplantation performed by our xenotransplantation research team since 2011. These included 42, 34, 3, and 21 kidney, heart, liver, and partial corneal transplants, respectively. In addition, the immunosuppressants used were anti-CD154, rituximab, anti-thymocyte globulin, rapamycin, and tacrolimus.

Results: The longest survival duration was 221, 217, and 1422 d for the kidney, heterotopic heart, and parietal corneal transplants, respectively. In contrast, the survival duration did not exceed 1 d in cases of liver transplantation. Furthermore, some immunosuppressants and anticoagulants exhibited the potential to improve clinical outcomes. These drugs have become clinically available and have functionally improved since their development.

Conclusions: Our findings indicate that the clinical application of xenografts in Korea depends on the development of multiple transgenic pigs and further development of immunosuppressants and anticoagulants.