Cyclosporine, sy kloh SPAWR een, is a drug that fights rejection of transplanted body tissues and organs. The drug is widely used in operations in which the heart, liver, pancreas, bone marrow, a kidney, or a lung of one person is transferred to another person. It is produced from cultures of the fungus Tolypocladium inflatum. Jean Borel, a Swiss immunologist, discovered the medicinal properties of cyclosporine in 1972. Cyclosporine was first used in transplant operations in 1981. Its use has reduced the number of complications and deaths resulting from transplants.