On January 21, according to foreign media reports, after David Bennett became the first patient to receive transgenic pig heart transplantation in the world, American doctors announced the successful transplantation of two pig kidneys into a brain dead human body, marking another "important step" in the life-saving xenotransplantation technology using animal organs. Jim Parsons, 57, from Huntsville, Alabama, died of head injury in cross-country cycling in September 2021. With the support of his family, researchers at the University of Alabama at Birmingham performed a groundbreaking transplant for Parsons only four days later. Parsons' own kidney was removed while the blood was still circulating, and then he was transplanted with two organs taken from transgenic pigs. The transplanted pig kidney can filter blood and produce urine. More importantly, there is no rejection. After transplantation, both organs survived for three days. The results show that xenotransplantation may help solve the global organ shortage crisis. Because pig hearts are similar to human organs in function and physiological structure, they are used as models for the development of new therapies. The first peer-reviewed study by doctors at the University of Alabama at Birmingham for Parsons' successful pig kidney transplantation was published in the American Journal of transplantation on Thursday. Director of the Institute of comprehensive surgical transplantation at the University of Alabama Birmingham Professor Jayme Locke, chief surgeon of the study, said: "This is a time to change the rules of the game in the history of medicine and an important milestone in the field of xenotransplantation. Xenotransplantation can be said to be the best solution to the crisis of organ shortage. We have closed the key knowledge gap and obtained the safety and feasibility data needed to start clinical trials in living people with end-stage renal failure. This study provides The knowledge that animal models cannot produce has brought us one step closer to the future of organ supply to meet the huge demand. " It is reported that Parsons is keen on riding cross-country bicycles, but an accident occurred while cycling in the woods on September 26 last year, resulting in his brain death and underwent transplantation on September 30. "Maintaining blood circulation is first to support transplanted organs, and then for our research," Professor Locke said Parsons is a registered organ donor for the Alabama organ procurement organization legacy of hope. He was eager to help others after his death, but his organs were not suitable for donation. His family allowed the University of Alabama Birmingham to continue to use the ventilator during the study to maintain Parsons' normal physical function. Paris' ex-wife Julie O'Hara said: "Parsons will want to save as many people as possible with his death. If he knows that doing so may save thousands of people, he will do so without hesitation. Our dream is that no one else will die for their kidneys. We know Parsons will be very proud because his death may bring more hope for others." Parsons' transplanted pig kidneys are taken from donated pigs raised in pathogen-free, surgical grade facilities, and then stored, transported and processed for implantation, just like human kidneys. Before surgery, Parsons and donor animals underwent cross matching tests to determine whether the transgenic organs matched well with their tissues. Cross matching is performed for each human kidney transplant. However, this tissue matching test between pigs and humans was developed by the University of Alabama at Birmingham, marking the first verification of prospective cross matching between the two species. The pig kidney is placed in the precise anatomical position used by the human donor kidney, connected with the renal artery, renal vein and ureter that transports urine from the kidney to the bladder. Parsons also received standard immunosuppressive therapy, in other words, to reduce the activity of the human immune system. When asked about the effect of transplantation in healthy patients compared with patients with brain death, Professor Locke said that there would be no difference in the process, but the results would be different. "The state of brain death is very bad and it is difficult to assess renal function (such as urine output and creatinine clearance), which is not surprising, because even in human to human transplantation, the kidneys of brain dead donors usually delay transplantation function, which means that these kidneys usually do not urinate for a week and take several weeks to clear creatinine," she said According to the surgical team, their process proves the long-term feasibility of such transplantation and how such transplantation may work in the real world. Professor Locke said: "This human preclinical model is a method to evaluate the safety and feasibility of pig to non-human primate models without risk to living people. Our research shows that the main obstacles to human xenotransplantation have been overcome, and new knowledge is needed to optimize human xenotransplantation results, so as to make progress for the establishment of new preclinical human models Further research has laid the foundation. " Transplanting pig organs into humans is expected to increase the number of organs available for transplantation and prevent a large number of patient deaths caused by organ shortage every year. According to statistics, at present, more than 800000 Americans suffer from renal failure. Because there are few available organs, most people have never been on the waiting list for transplantation. (Xinhua News Agency)