- Immunosuppression
Immunosuppression involves an act that reduces the activation or
efficacy of theimmune system . Some portions of the immune system itself have immuno-suppressive effects on other parts of the immune system, and immunosuppression may occur as an adverse reaction to treatment of other conditions. Deliberately induced immunosuppression is generally done to prevent the body from rejecting anorgan transplant , treatinggraft-versus-host disease after abone marrow transplant , or for the treatment ofauto-immune disease s such asrheumatoid arthritis orCrohn's disease . This is typically done using drugs, but may involve surgery (splenectomy), plasmapharesis, or radiation.A person who is undergoing immunosuppression, or whose immune system is weak for other reasons (for example,
chemotherapy andHIV patients) is said to be "immunocompromised". When an organ is transplanted, the immune system of the recipient will most likely recognize it as foreign tissue and attack it. The destruction of the organ will, if untreated, end in the death of the recipient.In the past,
radiation therapy was used to decrease the strength of the immune system, but now immunosuppressant drugs are used to inhibit the reaction of the immune system. The downside is that with such a deactivated immune system, the body is very vulnerable toopportunistic infection s, even those usually considered harmless. Also, prolonged use of immunosuppressants increases the risk ofcancer .Cortisone was the first immunosuppressant identified, but its wide range of side effects limited its use. The more specificazathioprine was identified in 1959, but it was the discovery of cyclosporine in 1970 that allowed for significant expansion ofkidney transplantation to less well-matched donor-recipient pairs as well as broad application ofliver transplantation ,lung transplantation ,pancreas transplantation , andheart transplantation .Dr.
Joseph Murray ofHarvard Medical School and chief plastic surgeon atChildren's Hospital Boston from 1972-1985 was awarded theNobel Prize in Physiology or Medicine in 1990 for his work on immunosuppression. Dr. Murray and his team are credited with first successful human kidney transplant at Peter Bent Brigham Hospital, Boston on 23 December 1954.ee also
*
immunosuppressant substances
**Immunosuppressive drug
*Transplant rejection
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