Scientists from the University of Maryland reported a second case of transplantation of a genetically modified pig heart into a patient with end-stage heart failure. The transplanted heart had 10 genes edited to prevent graft rejection, heart tissue proliferation and improve engraftment.
Man, 58 years old, Lawrence Fawcett, with end-stage heart failure, became the second patient to successfully receive a genetically modified pig heart, scientists at the University of Maryland Medical Center reported. The operation took place on September 20.
The patient was denied a donor heart transplant due to previously diagnosed peripheral vascular disease and previous internal bleeding. Xenotransplantation in this case became the only available treatment method.
After surgery, the researchers were convinced that the transplanted genetically modified heart was functioning correctly. No signs of hyperacute immune rejection were detected. Doctors emphasized that the patient will be closely monitored over the next few weeks to watch for signs of transplant rejection and transmission of swine infection, although preliminary studies did not reveal viruses, bacteria or parasites in the recipient.
In the transplanted heart, three genes responsible for human rejection of pig organs were switched off, and six genes responsible for graft survival were inserted. In addition, a gene was turned off to prevent excess growth of pig heart tissue. A total of 10 genes were edited.
Scientists noted that about 110 thousand Americans are waiting for organ transplantation and more than 6 thousand patients die annually without waiting for it. Xenotransplantation could save the lives of thousands of people. However, in addition to the danger of transmission of unknown pathogens from animals to humans, xenotransplantation is more likely to cause an immune response that can lead to immediate organ rejection and possible death of the patient.
As MV previously wrote, the first genetically modified pig heart was transplanted in early 2022 David Bennett, who was admitted to the University of Maryland Medical Center due to life-threatening arrhythmia. The man died two months after the transplant. Death was due to extensive interstitial cardiac edema and myocyte necrosis. The exact cause of the incident has not been established.