A Korean biotech venture company has taken a giant step towards transplanting pig organs into humans without triggering any complication. A team of scientists at MGenbio, a Korean venture that specializes in developing xenotransplant therapeutic application technologies using pig organs, has succeeded in cloning the world’s first pig with human genes. The research was carried out in cooperation with the state-run National Livestock Research Institute.
Lead scientist Dr Park Kwang-Wook stated that his team had cloned the pig by taking a somatic cell from a pygmy pig used to grow transplant organs, injecting the human HLA-G gene into it and implanting the cell into the womb of a female pig. Five cloned pigs were born by Caesarean section, but only one survived. As the cloned pig has been genetically modified to contain the HLA-G gene, its organs would have a greater chance of being accepted if they are transplanted into humans.
Immune rejection is one of the chief challenges behind cloning research. The human immune system attacks transplanted organs because it considers them invaders, and the process has to be suppressed with expensive life-long immunosuppressive therapies, which can have serious side effects, such as infection, diabetes and cancer. Without medication to suppress the immune response, transplanted organs are rejected. But now, cells from the cloned pig will reduce the power of human antibodies to kill the invader by 60-70 per cent. The pig’s organs, including the pancreas cells that secrete insulin, could be more easily transplanted into humans without rejection as it has the human immunity gene.
In 2002, a British biotechnology company had claimed a breakthrough in the quest to create organs for transplant from pigs into humans. This latest breakthrough could help in the treatment of diabetes. However, additional research to manipulate three to five immunity genes besides HLA-G is needed to make transplanting organs from cloned pigs a realistic proposition.