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Immune System and Transplant Anti-Rejection Drugs

The word "immune" derives from the Latin word for protection. Your immune system serves a protector against attacks by foreign substances known as antigens. An antigen is any substance that causes an immune response, such as bacteria or viruses. The purpose of your immune system is to help preserve your health; however, it cannot differentiate between a harmful substance and a transplanted organ. Thus, a transplanted organ is recognized as a foreign substance that should be defeated.

Due to this medical fact, your transplant surgeon has prescribed you certain medications to suppress your immune system and control its response to the transplanted organ. These drugs are called immunosuppressants (anti-rejection drugs), and they include: imuran (azathioprine), cellcept (myophenolate mofetil) prednisone (Deltasone, Kedral, Medrol, Orasone, Prelone, Sterapred DS), cyclosporine (Neoral), prograf (a brand of FK506) and rapamune (sirolimus). A basic understanding of your immune system will help you understand why these drugs play a crucial role in the success of your transplant.

Lymphocytes are the primary defenders of your immune system. They are the white blood cells and the only cells in your immune system with the ability to recognize antigens (any substance that induces an immune response). The cells of the immune system work together to resist or overcome infections in your body. There are different kinds of lymphocytes: B-Lymphocytes react to antigens in solution, such as the blood; T-Lymphocytes react to infected cells, or foreign cells such as a transplanted organ.

The cells of the immune system are produced in the bone marrow and then travel to different parts of the body to mature. The resulting inactive T and B Lymphocytes then relocate in the lymph nodes, spleen and tissues where they remain inactive until they recognize a specific antigen.

© Copyright April 2004 - Latino Organization for Liver Awareness / Revised on March 2009