According to Dr. Starzl, recent research advances, particularly those related to drugs which interact with the immune system, have enabled his team to perform the operation. Combatting rejection , especially in a xenotransplant model, is the ultimate challenge faced by those engaged in transplantation research. FK506, a drug manufactured by Fujisawa Pharmaceutical Co., Ltd., of Japan and developed at Pitt to combat rejection, works to suppress the recipient's T-cells from attacking the donor organ. T-cells are one type of white blood cell important to the immune system. Cyclophosphamide, a Bristol-Myers Squibb drug developed to treat cancer, was shown to hold promise for transplant recipients by Dr. Starzl more than 20 years ago.
Antibodies help destroy the foreign substance.
Prednisone is a steroid hormone that affects those cells which help recognize and process antigens, while prostaglandin serves to subdue the chain reaction of events likely to occur in the immune system. Early rejection in xenotransplantation primarily involves the humoral response and can be rapid and uncontrollable if the recipient has natural antibodies to another species' antigens. Pitt researchers conducted laboratory studies which found no natural antibodies specific to baboon antigens in the human immune system. Another point in our favor is the liver itself. In humans, we have found the liver to be more resistant to humoral rejection than any other organs which are transplanted.