It was an ordinary day. Reading in my latest "TIME" magazine about transplanting pig kidneys into humans. It was this past March 16 that a transplant-surgery team at Massachusetts General Hospital successfully transplanted a modified pig kidney into a human. The groundbreaking, four-hour surgery was the culmination of years of work transplanting kidneys from a specially bred group of pigs - genetically modified to more closely resemble those of humans - into primates. Encouraged by those results, the team of surgeons at Mass General Brigham was confident it was time to test the pig organ in the first human patient. That patient, a Mr. Richard Slayman, a manager at the Massachusetts department of transportation, had received a human kidney transplant five yers ago but as its often the case with kidney disease, the organ began to fail and he continued to need dialysis. His health progressively worsened to the point that he couldn't carry on like that, said Dr. Winfred Williams, Mr. Slayman's physician. Dr. Tatsuro Kawai, director of the hospital's Center for Clinical Transplant Tolerance, who had performed the operation previously, also performed the pig-kidney surgery. As more than a dozen people watched, Kawai carefully connected the pig kidney to Slayman's circulatory system. The size of the pig kidney was exactly the same as the human kidney and upon restoration of blood flow into the kidney, the kidney pinked up immediately and started to make urine. When they first saw the urine output, everyone in the operating room burst into applause. It was truly the most beautiful kidney they had ever seen. The kidney came from a special group of pigs bred to produce human-like kidneys. Biotech company eGenesis worked closely with the hospital to produce them, using genetic innovations developed over recent decades. The pigs' cells were treated with the gene-editing technology CRISPR, which allows scientists to make very precise genetic changes in cells. These cells were then used to create pig clones so the pigs would have identical and consistent genetic changes. Their kidneys were then transplanted first into primates, and finally into Slayman. All told, the pig kidneys contained 69 genetic changes: The scientists knocked out or eliminated three pig genes that trigger immediate rejection by the human immune system, added seven human genes to make the pig tissue appear more human to the immune cells, and inactivated viral genes in pig cells that could cause infections. They also used a unique cocktail of antibody treatments to further dampen the immune reaction to the transplanted kidney. Unbelievable!! The company is working on other pig organs as well. In January, eGenesis partnered with researchers at the University of Pennsylvania to transplant a genetically modified pig liver into a brain-dead patient. That work, along with Slayman's experience, is making a strong case for the role of pig organs for patients on waiting lists. More than 100,000 people are placed on the kidney-transplant waiting list in the USA each year; only 20,000 kidneys are available. More transplants may provide a better idea of how long the pig kidneys function and whether they can meaningfully extend the length and quality of a patients' life. For now, patients might benefit from receiving a pig kidney temporarily as they wait for a human one. Such bridging can be critical for patients like Slayman; while on dialysis, he experienced clotting issues and required dozens of surgeries to improve his circulation. Will the pig kidney be a solution or just a stop-gap while waiting on a human kidney? At least today there is a glimmer of hope that their may be a better and longer waiting period by use of a healthy pig kidney. Or...maybe, just maybe, the pig kidney might be the permanent answer for others. I guess, as the saying goes, only time will tell.
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