Editing Immunosuppression (section)

==Deliberately induced==
{{further|Immunosuppressive drug}}
[[File:Azathioprine3Dan.gif|thumb|120 px|left|Azathioprine]]
[[File:SEM blood cells.jpg|thumb|White blood cells (and red blood cells)]]
Administration of [[immunosuppressive drug|immunosuppressive medications]] or immunosuppressants is the main method for deliberately inducing immunosuppression; in optimal circumstances, immunosuppressive drugs primarily target hyperactive components of the immune system.<ref>{{Cite journal|last=Wiseman|first=Alexander C.|date=2016-02-05|title=Immunosuppressive Medications|journal=Clinical Journal of the American Society of Nephrology|volume=11|issue=2|pages=332–343|doi=10.2215/CJN.08570814|issn=1555-9041|pmc=4741049|pmid=26170177}}</ref> People in remission from cancer who require immunosuppression are not more likely to experience a recurrence.<ref>{{cite journal|last1=Shelton|first1=Edward|last2=Laharie|first2=David|last3=Scott|first3=Frank I.|last4=Mamtani|first4=Ronac|last5=Lewis|first5=James D.|last6=Colombel|first6=Jean-Frederic|last7=Ananthakrishnan|first7=Ashwin N.|title=Cancer Recurrence Following Immune-Suppressive Therapies in Patients With Immune-Mediated Diseases: A Systematic Review and Meta-analysis|journal=Gastroenterology|date=July 2016|volume=151|issue=1|pages=97–109.e4|doi=10.1053/j.gastro.2016.03.037|pmid=27039969|pmc=4925196}}</ref> Throughout its history, [[radiation therapy]] has been used to decrease the strength of the immune system.<ref>{{Cite book|url=https://books.google.com/books?id=w5bBCwAAQBAJ&q=radiation+therapy+decreases+strength+of+immune+system&pg=PA28|title=Mosby's Guide to Nursing Diagnosis - E-Book|last1=Ladwig|first1=Gail B.|last2=Ackley|first2=Betty J.|last3=Makic|first3=Mary Beth Flynn|date=2016-03-15|publisher=Elsevier Health Sciences|page=28|isbn=9780323390279|language=en}}</ref>  Dr. Joseph Murray of Brigham and Women's Hospital was given the [[Nobel Prize in Physiology or Medicine]] in 1990 for work on immunosuppression.<ref>{{Cite web|url=https://www.nobelprize.org/nobel_prizes/medicine/laureates/1990/murray-facts.html|title=Joseph E. Murray - Facts|website=www.nobelprize.org|access-date=2017-05-12}}</ref>

Immunosuppressive drugs have the potential to cause [[immunodeficiency]], which can increase susceptibility to [[opportunistic infection]] and decrease [[cancer immunosurveillance]].<ref>{{Cite web|url=https://www.cancer.gov/about-cancer/causes-prevention/risk/immunosuppression|title=Immunosuppression|website=National Cancer Institute|language=en|access-date=2017-07-13|date=2015-04-29}}</ref> Immunosuppressants may be prescribed when a normal immune response is undesirable, such as in [[autoimmune diseases]].<ref>{{Cite journal|last=Chandrashekara|first=S.|date=2012|title=The treatment strategies of autoimmune disease may need a different approach from conventional protocol: A review|journal=Indian Journal of Pharmacology|volume=44|issue=6|pages=665–671|doi=10.4103/0253-7613.103235|issn=0253-7613|pmc=3523489|pmid=23248391 |doi-access=free }}</ref>

Steroids were the first class of immunosuppressant drugs identified, though side-effects of early compounds limited their use. The more specific{{Vague|date=March 2021}} [[azathioprine]] was identified in 1960, but it was the discovery of [[ciclosporin]] in 1980 (together with azathioprine) that allowed significant expansion of [[organ transplantation|transplantation]] to less well-matched donor-recipient pairs as well as broad application to  [[lung transplantation]], [[pancreas transplantation]], and [[heart transplantation]].<ref name=emed1/> After an [[organ transplantation]], the body will nearly always reject the new organ(s) due to differences in [[human leukocyte antigen]] between the donor and recipient. As a result, the immune system detects the new tissue as "foreign", and attempts to remove it by attacking it with  [[leukocytes|white blood cells]], resulting in the death of the donated tissue. Immunosuppressants are administered in order to help prevent rejection; however, the body becomes more vulnerable to infections and malignancy during the course of such treatment.<ref>{{Cite web|url=https://medlineplus.gov/ency/article/000815.htm|title=Transplant rejection: MedlinePlus Medical Encyclopedia|website=medlineplus.gov|language=en|access-date=2017-07-14}}</ref><ref>{{Cite journal|date=2017-03-09|title=Immunology of Transplant Rejection: Overview, History, Types of Grafts|url=http://emedicine.medscape.com/article/432209-overview#a7}}</ref><ref>{{Cite journal|last1=Charles A Janeway|first1=Jr|last2=Travers|first2=Paul|last3=Walport|first3=Mark|last4=Shlomchik|first4=Mark J.|date=2001|title=Responses to alloantigens and transplant rejection|publisher=Garland Science |url=https://www.ncbi.nlm.nih.gov/books/NBK27163/|language=en}}</ref>