PITTSBURGH -- In a renewed effort to help relieve the dire shortage of human donor organs, surgeons from the University of Pittsburgh yesterday took a liver from a baboon and implanted it in a human patient.
The recipient was a man dying from hepatitis B, a virus that had destroyed his liver and made him ineligible to receive a donated human organ.
The operation, which began shortly before noon, continued last night.
The patient's name is not being released because of his desire for confidentiality.
On Friday, a committee that evaluates the ethics of human experiments at the university gave permission to a team headed by the liver transplant pioneer, Dr. Thomas E. Starzl, to perform up to four permanent baboon-liver transplants in humans.
It is the first time that a baboon liver is being given to a human, although other baboon organs have been transplanted to humans in at least 33 operations since 1905. So far, none has been successful.
The man signed a detailed consent form, approved by the ethics committee, that spelled out everything that could go wrong with the experimental operation.
In keeping with the committee's orders, the surgeons waited another 24 hours to give the patient a chance to pull out in case of second thoughts.
After agreeing to go ahead, he began taking the first of four drugs developed by the Pittsburgh team to prevent rejection of the baboon liver.
One of the drugs, known as FK-506, is new and may help this operation succeed where all other animal-to-human transplants have failed. Because the hepatitis B virus reinfects transplanted human livers, hospitals have excluded these patients from the long queue of would-be liver recipients, but the baboon liver is thought to be not susceptible to the virus.
Also, a baboon was chosen for the cross-species transplant because its liver is anatomically similar to the human organ.
If the new combination of drugs allows successful baboon liver transplants, surgeons would go on to try it for other organs so that baboons could be raised for a dependable, ready supply of organs for humans. The baboon is not an endangered species and can be bred safely and easily in captivity. The baboon sacrificed yesterday was born in the United States and raised at a site approved by the Food and Drug Administration.
Success would go a long way toward relieving the shortage of human organs for transplantation and would allow transplants to be done more on a scheduled elective instead of an emergency basis.
Each week, about three patients die here while waiting for a liver transplant and about 30 percent of all patients waiting for a human liver die before getting one, Dr. Starzl said. Many are under age 45.
"The only way out" is to give animal organs to humans, Dr. Starzl told the ethics committee before it approved his experiment.
The liver, "the organ for which there is the greatest present need, is the one with the greatest chance of success," he also said.
In the most recent animal-to-human transplant, an infant known as Baby Fae died 20 days after receiving a baboon's heart at Loma Linda Medical Center in California in 1984.
Baby Fae received cyclosporine, a standard anti-rejection drug that was not included in the combination of drugs being given to the man who received the baboon liver yesterday, and a steroid drug.
Dr. Starzl performed the world's first human liver transplant in 1963 and the first successful liver transplant in 1967, both at the University of Colorado in Denver.
Since then, more than 10,000 human liver transplants have been performed.