Lab Med Online.  2023 Oct;13(4):275-281. 10.47429/lmo.2023.13.4.275.

Overcoming Immunological Barriers in Xenotransplantation: A Historical Review of Previous Research and Future Directions

  • 1Department of Laboratory Medicine, Hallym University College of Medicine, Chuncheon, Korea


The shortage of human donor organs is a major concern in clinical transplantation. Xenotransplantation, the transplantation of animal organs into humans, is a procedure that aims to solve this problem. Unfortunately, this ambitious idea has a long, fascinating, but disappointing history. Among the many obstacles to xenotransplantation, immunological barriers and molecular incompatibility between species are the most challenging. Recent advances in gene editing techniques and the development of targeted immune suppressive agents have pushed xenotransplantation closer to clinical application. In 2022, the first patient that received porcine heart transplantation in the United States showed no sign of hyperacute rejection. Although the patient did not survive for a long time, this controversial clinical trial proved that previous research data have been crucial in improving the viability of porcine donor organs in clinical transplantations. Xenotransplantation has shown a slight progress in its clinical application. However, further progress necessitates extensive and challenging research, but is worth pursuing. This article covers previous scientific endeavors and future directions in xenotransplantation research.


Xenotransplantation; Pig; Genetic modifications; Nonhuman primates; Rejection


  • Fig. 1 Schematic illustration of hyperacute rejection (A) and delayed xenograft rejection (B).

  • Fig. 2 Strategies for porcine islet xenotransplantation.


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