What is the primary use of cyclosporin in medical treatment?

Cyclsporine is primarily utilized to prevent transplant rejection by suppressing the immune system. It is an immunosuppressant that inhibits the activity of T-lymphocytes, which play a crucial role in the body’s rejection response to foreign tissues, such as transplanted organs. This is particularly important for patients who have undergone organ transplantation, as their bodies can recognize the new organ as a threat and initiate an immune response against it. By using cyclosporine, the risk of organ rejection is reduced, helping to ensure that transplanted organs can function properly in the recipient's body.

The use of cyclosporine in preventing transplant rejection is well-established and supported by extensive clinical research. This differentiates it from the other options, which do not align with the primary purpose of cyclosporine. While it may have some ancillary uses in various contexts, its main application remains in transplant medicine.