62-year-old dies two months after a pig kidney transplant

After a team of surgeons at Massachusetts General Hospital (MGH) successfully transplanted a pig's kidney into a living human for the first time, the 62-year-old patient died almost two months after the procedure. The MGH had previously reported that he was recovering well from the four-hour operation under the direction of Tatsuya Kawai and Nahel Elias. However, the death had nothing to do with the transplant, the medical team assured in a statement from the MGH.

For the cross-species transplantation (xenotransplantation), a pig kidney genetically modified with the CRISPR/Cas9 gene scissors was used from the biotech company eGenesis, with whom the MGH has been working for five years, according to the MGH. In total, the company made a "record number of 69 genetic modifications" to the miniature pig bred for organ harvesting to reduce the recipient's immune response.

The genetic modifications made by the company are intended, among other things, to reduce the risk of viral infection in the recipient, according to a report published in Nature. In the past, two men who had received pig hearts had died. In one case, according to the scientists, an infection of the heart was the cause of death, not the transplant itself.

Transplant approved due to lack of alternatives

The patient was considered as a recipient because he had developed terminal renal failure due to diabetes and high blood pressure, according to the Nature article. A kidney received from a human donor six years ago had failed about a year ago. The US Food and Drug Administration (FDA) had therefore approved the transplantation as "compassionate use" due to the emergency – a special regulation for life-threatening cases without alternative treatment options.

Xenotransplantations with other pig organs

According to its own information, eGenesis is in talks with the FDA to research pig kidneys, livers and hearts for pediatric use in clinical trials.

Others are also researching xenotransplants with pig organs. A few days ago, Chinese researchers transplanted a pig liver into a brain-dead human and, according to Nature, kept it functional for ten days; eGenesis succeeded in doing the same for two days in a similar experiment. The operation was carried out at the Xijing Hospital of the Air Force Medical University in Xi'an, China, to test the potential of genetically modified pig organs for future transplants.

As in the case described above, the pig liver was removed from a genetically modified minipig and connected to the blood vessels of the 50-year-old, clinically dead recipient. The Chinese researchers are planning to use the procedure on another clinically dead patient soon.

(mack)