Media release

From: Springer Nature

Long-term observation of a pig-to-human kidney transplant

A detailed analysis of the immune response to a pig-to-human kidney transplant in a brain-dead patient over a period of two months is reported in two studies published in Nature this week. These results could contribute to a better understanding of the reasons for and markers of xenotransplant failure, with aims to improve patient outcomes in future studies.

Xenotransplantation (transplanting an organ from one species to another) has been presented as a potential solution to a shortage of available donors for patients with end-stage organ failure. The transplantation of genetically modified pig kidneys in conjunction with treatment to suppress the immune response has shown some promise. However, organ rejection is a common complication for all types of transplantation and is even less understood when using an organ from another species. The immune response that leads to the rejection is not completely understood, as studies mapping this process have previously been limited by short follow-up periods.

Robert Montgomery, Brendan Keating, and colleagues have developed a detailed map of the immune response over a relatively long-term period after transplanting a genetically modified pig kidney into a brain-dead patient. They find that the kidney was able to function in a life-sustaining capacity for 61 days before the experiment was ended, despite undergoing two rejection episodes during this period. These episodes were successfully treated with existing therapeutics and renal function remained stable. The authors were able to identify key pathways of immune cell mobilization in response to the transplant and have mapped the genomics associated with these pathways in a second paper.

These studies provide a detailed map of the human immune response to the xenotransplantation of a genetically modified pig kidney. Further work will be needed to apply these insights to promote long-term transplant success.