An American woman received a heart pump and a genetically modified pig kidney with thymus
US surgeons fitted the patient with a ventricular assist device and transplanted a pig kidney with an edited genome. She became the second living patient with such an organ, and the first to receive it for severe heart failure. This is stated in a press release of the clinic of New York University, where the operations took place.
Experiments with the organs of genetically modified pigs are designed to help solve the problem of the shortage of donor organs. Modifications are made to their genome to reduce the likelihood of an immune reaction of transplant rejection and inactivate viruses embedded in pig DNA. In preclinical trials, the heart and kidney of such animals worked in monkeys for several years. Humans were transplanted with GM pig skin. The GM pig heart was given to one living patient (he lived about two months) and two with brain death. The first two GM kidneys were also transplanted into patients with brain death (one organ was simply connected to the blood vessels but left outside the body, the other was transplanted completely). In March 2024, doctors at Massachusetts General Hospital transplanted such an organ for the first time for therapeutic purposes, it took root and worked, the 62-year-old patient no longer needed dialysis and was discharged in a few weeks in satisfactory condition.
New Jersey resident Lisa Pisano, 54, suffered from both severe heart and kidney failure and suffered a non-fatal cardiac arrest. Due to her severe general condition and circulatory failure, she could not be placed on a waiting list for a donor kidney, and because she was on hemodialysis, she could not be fitted with a ventricular assist device (LVAD), a pump that takes over some of the functions of the left ventricle of the heart and helps pump blood through the great circle of the circulation. According to doctors' estimates, the patient's condition was close to terminal.Specialists from NYU Langone Medical Centre proposed the experimental treatment to the patient and, after securing her consent, obtained emergency approval from the US Food and Drug Administration (FDA) to carry it out. On 4 April, cardiac surgeons led by Nader Moazami placed the woman's LVAD. Eight days later, when the circulatory failure was compensated, a team of transplant surgeons led by Robert Montgomery, director of the New York University Transplant Institute, transplanted a genetically modified pig kidney and thymus tissue, the latter designed to adapt the patient's immune system to an animal organ; it was placed under the kidney capsule.
The experimental GM kidney with thymus tissue ("xenograft") under the working name UThymoKidney was created by United Therapeutics. It contains a single modification - a knockout of the gene responsible for the synthesis of the non-human immunogenic sugar galactose-alpha-1,3-galactose (alpha-gal). By comparison, eGenesis' EGEN-2784 GM kidney, which the Massachusetts patient received, contains 69 modifications but no thymus gland tissue.
Pisano thus became the second recipient of a porcine GM kidney (and the first to receive one in combination with a thymus), the first woman to undergo such an intervention, and the first patient to receive a transplant (of any kind) after LVAD placement. The organ started to produce urine immediately after transplantation, no signs of rejection were observed. Now the patient's condition is stable, she is taking standard immunosuppressive drugs and is trying to take her first steps with a walker. Montgomery regards the progress of her recovery as good, but is cautious about making long-term predictions.
While some researchers are creating genetically modified pig organs for xenotransplantation, others are trying to grow real human kidneys in pigs.