Genetically Modified Pig Raises Hope for Organ Transplants

Korean scientists have created a genetically modified pig whose organs can be used for transplanting into human patients. The cloned piglet was born by a surrogate mother on April 3 and remains healthy at a lab at the National Institution of Animal Science in Suwon, Gyeonggi Province.The researchers have predicted the mass production of these hybrid pigs capable of producing humanized organs and organ parts, including pancreatic islets of Langerhans, heart valves and entire hearts. But they have yet to prove the organs can be transplanted into human patients without risk to life. The piglet is part of the ``mini-pig'' species that grow up to just around 80 kilograms. The study was part of a comprehensive project financed by the Ministry of Education, Science and Technology to develop new technologies for drug development and genetically modified organs for use in human transplants. The piglet was born after trial and error tests for the past six years with a budget of $3.38 million.Scientists worldwide have gone all-out to create organ farms in animals, which they believe could help solve one of medicine's fastest growing problems ― the shortage of organs for transplant surgeries. However, creating animal organs that are compatible with the human immune system has proved to be a difficult challenge. Although drugs can stop the body from rejecting a human transplant, the immune system won't accept animal organs for an extended period of time. This is because that the antibodies in human blood are directed to attack alpha 1, 3-galactose, or ``alpha gal,'' which is found in the tissues of all non-primate mammals. The transplanted animal organs often fail to survive for less than a few hours. The Korean researchers were to produce a ``GAL-knockout'' pig, which is genetically removed of alpha gal that triggers the immune rejections. They first removed one of the two genes (a1, 3-Galactosyltransferase) from a somatic cell of a mini-pig and then inserted the cell to an egg removed of its nucleus to create a clone. The produced piglet could eventually be used to breed genetically modified pigs born without alpha gal, which may have a better chance of producing compatible human organs, the scientists said.Lee Kyung-kwang, the leader of the team, died on March 1. Other members include Seoul National University's Jeong Jun-ho, Dankook University's Shim Ho-sup, Konkuk University's Kim Jin-hoi, Animal Science Institute's Park Su-bong and Chonnam National University's Kang Man-jong. A number of breakthroughs have been reported on the research for GAL-knockout pigs. In 2005, a Harvard University team transplanted the heart of a one to a baboon, and the animal lived on for another six months. It could be argued that the track record for xeno-transplantation ― using animal organs to replace human ones ― has been disastrous. In 1984, a newborn baby, called by the media as ``Baby Fae,'' received a baboon heart in California, but managed to live for just 20 days. In 1999, Jeff Getty, an American AIDS patient, received bone marrow from a baboon. Doctors had hopes that the immune cells in the baboon's marrow would replace those Getty had lost to AIDS, as baboon cells are naturally resistant to HIV. However, the cells functioned for only a brief time and Getty died 11 years later from heart failure. In 1999, a 35-year-old American HIV patient received a baboon liver, but died just two months after the transplantation after contracting a virus that is known to only affect the animal