Pigs' Hearts Beat for a Year in Baboons' Abdomens

By -- Robert PreidtAugust 20, 2014

Pigs' hearts transplanted into baboons survived for more than a year, which is twice as long as previously achieved, researchers report.

The work is part of efforts to find ways to use animal organs to shorten transplant waiting lists.

In this study, scientists transplanted hearts from genetically engineered piglets into baboons' abdomens. The genetic engineering and new methods of suppressing the baboons' immune system response are what enabled the hearts to survive for more than a year.

The genetic manipulation involved removing genes that trigger attack by the human immune system, and inserting genes that are more compatible, according to the study published recently in The Journal of Thoracic and Cardiovascular Surgery.

The next step is to replace the baboons' hearts with the genetically engineered pigs' hearts to find out if the transplanted hearts can keep the baboons alive.

About 3,000 people in the United States are on the waiting list for a heart transplant, but only 2,000 donor hearts become available each year, according to background information in a journal news release. Transplantation using animal organs (xenotransplantation) is seen as a possible way to save the lives of people on transplant waiting lists.

"Until we learn to grow organs via tissue engineering, which is unlikely in the near future, xenotransplantation seems to be a valid approach to supplement human organ availability. Despite many setbacks over the years, recent genetic and immunologic advancements have helped revitalized progress in the xenotransplantation field," lead investigator Dr. Muhammad Mohiuddin, of the Cardiothoracic Surgery Research Program at the U.S. National Heart, Lung, and Blood Institute, said in the news release.

Pigs are being studied because their anatomy is compatible with humans and they are a widely available source of organs, among other reasons. However, animal research does not always pan out in humans.