When has xenotransplantation worked?

Xenotransplantation, the transplantation of organs or tissues between different species, has seen limited success in experimental settings. Notably, in 2021, researchers successfully transplanted a genetically modified pig heart into a human patient in a groundbreaking surgery, marking a significant milestone in the field. Additionally, studies have shown promise with pig kidney transplants in non-human primates, demonstrating functionality for extended periods. However, widespread clinical application remains challenging due to immune rejection and ethical concerns.