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.
Cyclosporine prevents a person’s immune system from attacking a transplanted organ as if it were a dangerous invader. The drug blocks production of a type of white blood cells called T-helper cells that recognize and attack foreign invaders. T-helper cells identify transplanted tissues as foreign and attack them. This attack causes the body to reject the transplant. In addition to its use before and after transplant operations, cyclosporine helps treat certain diseases in which T-helper cells attack a person’s own tissues.
Patients may take cyclosporine orally in capsules or as a liquid. The drug also may be injected into the bloodstream. Cyclosporine may produce a number of side effects. The most serious of these effects include high blood pressure, reduced kidney function, liver damage, and abnormal growth of hair. To reduce its toxic effects, cyclosporine is often given in combination with several other drugs.
