A tissue transplant is the surgical removal of donor tissue from one human and the implantation of the tissue in another human recipient. The tissue can be skin, corneas, cartilage, or even bones. Kidneys, liver, lungs, and the heart are other commonly transplanted tissues. Most donors are cadavers but some tissue, like the kidneys or a lobe of the liver, can come from a living donor. One cadaver donor can donate enough healthy tissue to transplant to nearly 50 people.
The tissue transplant can be necessary for a variety of medical conditions. A person with severe burns might need a skin graft to help the healing process. Someone with failing lungs may need a lung transplant. A heart transplant can be a lifesaver for someone with heart disease. People with impaired renal function on dialysis may no longer need dialysis after a kidney transplant.
Donor tissue will need to be tested to ensure that communicable diseases, such as human immunodeficiency virus (HIV), acquired immunodeficiency syndrome (AIDS), or hepatitis are not transmitted to the recipient. The donor’s medical background will be evaluated, as well as his physical condition at the time of donation. Not all people that fill out the organ donation cards will be eligible for tissue donation at the time of death.
Tissue transplant rejection is a possibility for the entirety of the time the tissue is implanted in the new body. The risk of transplant rejection is greatest after one week. This is because the immune system requires time for the T-cells to become active and for antibodies to be created against the new tissue. Any tissue or organ that quits functioning after a period of a few months is part of a process called chronic rejection.
All tissue transplants cause the immune system of the recipient to become activated against the new tissue. The implanted tissue is treated as a foreign invader and antibodies are formed to destroy it. People that have an organ or tissue transplant are required to take immune system repressing medications daily for life.
Treatment of tissue rejection usually begins with a high dose of corticosteroids. Some people need a combination of steroids and a calcineurin inhibitor to treat the transplant rejection. A bone marrow transplant to replace the entire immune system may remove the threat of transplant rejection if the bone marrow donor has the same tissue type as the tissue donor. If the tissue transplant rejection cannot be stopped, the organ will fail and the person may die as a result.