On January 10 this year, a team of surgeons at the University of Maryland School of Medicine in the United States successfully transplanted the heart of a genetically modified pig into a 57-year-old male terminally ill patient, which was the world's first heart xenograft.
Three days after the operation, the patient was still in good condition. This is the first time that a genetically modified pig heart can function like a human heart without immediate rejection.
However, the terminally ill patient who received the heart of a genetically modified pig died two months after surgery.
On March 9, local time, The Maryland Hospital announced that 57-year-old David Bennett had died on March 8. The exact cause of death has not yet been determined, but doctors say his condition has deteriorated for several days.
David Bennett (third from left)
Bennett's son, David Jr, praised the hospital's attempts to save his father's life through surgery and said his family hoped the operation would help solve the problem of a shortage of transplanted organs.
Bennett with son David Jr
Six weeks before the groundbreaking surgery, Bennett had been hospitalized with a life-threatening arrhythmia and was attached to extracorporeal membrane oxygenation (ECMO) to sustain life. In addition to not being eligible for organ transplants, he was considered ineligible to use an artificial heart pump due to arrhythmias.
Bennett once said: "Either die or have a transplant." I want to live. I knew it was a gamble, but it was also my last resort. ”
Organs from transgenic pigs have been the focus of xenotransplantation studies, in part due to physiological similarities between pigs, humans and non-human primates.
In donor pigs, three genes associated with human rapid antibody-mediated porcine organ rejection were knocked out, and six human genes responsible for immune reception were inserted into the genome. Finally, to prevent overgrowth of the pig's heart tissue, an extra gene in the pig's body is knocked out. In total, a total of 10 specific gene edits were performed in donor pigs.
For decades, scientists have dreamed that xenotransplantation could one day be achieved, using animal organs to solve the shortage of organs available for human transplantation. According to U.S. federal data, about 110,000 Americans are currently waiting for organ transplants, and more than 6,000 patients die each year before waiting for their organs.
Xenotransplantation promises to save thousands of lives.
At the end of last year, the Langone Medical Center of New York University in the United States conducted two special experiments, and successfully transplanted the kidneys derived from pigs into the human body for the first time, and there was no rejection reaction within three days.