David Bennett Sr. who was the world’s first human recipient of genetically modified pig heart has died. According to the scientists of the Massachusetts Institute of Technology (MIT), he may have died of ‘a porcine virus’ present in the pig’s heart. The scientists said in their latest report quoting transplant specialists.
According to Dr. Muhammad Mohiuddin, who co-led the University of Maryland Medicine team, that performed the transplant on January 7 when Bennett was in a weak state, the virus called pig cytomegalovirus or CMV might have been one of several factors that contributed to his eventual demise. Bennett died two months after receiving the pig heart, which itself was a last-ditch effort to save his life.
According to the reports, the autopsy after Bennett’s death revealed that while the pig heart had been pumping well, scar tissue was building up in the organ, thickening it and preventing it from fully relaxing after pushing through the blood. Another examination highlighted the presence of pig cytomegalovirus, the porcine version of a very common human virus usually kept in check by the immune system. PCR analysis of tissue from Bennett’s heart showed some viral DNA, though researchers found no clear signs of infection, as per reports.
Mohiuddin also stated that the pig CMV clearly came from the transplant and was not something Bennett caught earlier, although the pig had been checked for the virus using all available testing methods. Moreover, no scientific evidence suggests a pig CMV infection could cause the thickening seen in Bennett’s heart, but it can’t entirely be ruled out.
“All these things were going on and all contributed to his up and down condition. Whether all of them contributed a little bit (to his death) or one contributed more than another, that’s the difficult part,” said Mohiuddin, whose team plans to publish its findings shortly in a scientific journal.
Mohiuddin also stated that understanding precisely what led to Bennett’s death will help the field avoid similar situations in the future.
Last year, doctors at the University of Maryland approached him with a never-before-tried option. They could replace his heart with one from a pig that had been gene-edited to make it less likely to be rejected by the human body. Bennett, 57, who had spent time in prison for stabbing a man in a barroom brawl in the 1980s, decided to take one more shot at life. The doctors revealed that the transplant procedure went well overall, but during the operation, his aorta, the body’s main artery, began to come apart. Surgeons had to quickly implant a graft and a stent to shore it up.
According to the scientists, the procedure might also have been a contributing factor to his eventual death. Meanwhile, animal-rights group People for the Ethical Treatment of Animals said the presence of the pig virus highlighted a long-term concern that using pig organs will transmit viruses to people.
“The public has little appetite for experimenters’ folly-prone, blind tinkering that wastes lives, time, and money, while potentially exposing the public to new viruses that mutate as they jump from species to species. Xenotransplantation should be relegated to the garbage heap of arrogant, speciesist vanity projects that harm more than they help,” PETA Senior Vice President Kathy Guillermo said in a statement. Mohiuddin also suggested that Bennett’s death did not discourage the field of xenotransplantation.