Abstract
The concept of replacing failing organs or tissues with healthy ones is as old as civilization itself, but it was not until 1954 that the first successful human kidney transplant was performed. Since then, improved surgical techniques and organ preservation, greater understanding of immunologic barriers, and the development of newer and more potent immunosuppressives have combined to make human organ transplantation relatively routine. Key to the success of transplantation is tacrolimus, originally known as FR000506. The compound, which suppresses interleukin-2 production associated with T-cell activation, inhibits differentiation and proliferation of cytotoxic T cells. Today, it is recognized worldwide as the cornerstone of immunosuppressant therapy.