definition : any structural or functional damage produced by the action of immunologically competent...
TRANSCRIPT
![Page 1: DEFINITION : Any structural or functional damage produced by the action of immunologically competent cells or antibodies against the normal cells is known](https://reader036.vdocuments.us/reader036/viewer/2022062804/5697bf831a28abf838c861d8/html5/thumbnails/1.jpg)
AUTOIMMUNITY
![Page 2: DEFINITION : Any structural or functional damage produced by the action of immunologically competent cells or antibodies against the normal cells is known](https://reader036.vdocuments.us/reader036/viewer/2022062804/5697bf831a28abf838c861d8/html5/thumbnails/2.jpg)
• DEFINITION:Any structural or functional
damage produced by the action of immunologically competent cells or antibodies against the normal cells is known as autoimmunity
![Page 3: DEFINITION : Any structural or functional damage produced by the action of immunologically competent cells or antibodies against the normal cells is known](https://reader036.vdocuments.us/reader036/viewer/2022062804/5697bf831a28abf838c861d8/html5/thumbnails/3.jpg)
CONTRADICTION IN TERMINOLOGY
Autoimmunity literally means ‘protection against self’ but it actually means ‘injury to self’
The term ‘autoallergy’ has been suggested but the term autoimmunity has wide usage.
![Page 4: DEFINITION : Any structural or functional damage produced by the action of immunologically competent cells or antibodies against the normal cells is known](https://reader036.vdocuments.us/reader036/viewer/2022062804/5697bf831a28abf838c861d8/html5/thumbnails/4.jpg)
HISTORY• Metalnikoff(1900) observed
sperm immobilising antibodies against the sperms of their own in guinea pig. This was the earlist example of autoimmunity.
• Donath and landsteiner(1904) identified circulating autoantibodies in paroxysmal cold hemoglobinuria. This was the first description of autoimmune disease in human beings
![Page 5: DEFINITION : Any structural or functional damage produced by the action of immunologically competent cells or antibodies against the normal cells is known](https://reader036.vdocuments.us/reader036/viewer/2022062804/5697bf831a28abf838c861d8/html5/thumbnails/5.jpg)
• Even though autoantibodies are harmful to body, some autoantibodies like anti-idiotypic antibody are essential for normal functioning of immune system.
![Page 6: DEFINITION : Any structural or functional damage produced by the action of immunologically competent cells or antibodies against the normal cells is known](https://reader036.vdocuments.us/reader036/viewer/2022062804/5697bf831a28abf838c861d8/html5/thumbnails/6.jpg)
Autoimmunity can be explained in experimental animals by injection of self antigens along with complete Freund’s adjuvant.
![Page 7: DEFINITION : Any structural or functional damage produced by the action of immunologically competent cells or antibodies against the normal cells is known](https://reader036.vdocuments.us/reader036/viewer/2022062804/5697bf831a28abf838c861d8/html5/thumbnails/7.jpg)
Diseases of autoimmune origin exhibit following features:
• An elevated level of immunoglobulins
• Demonstrable autoantibodies• Deposition of immunoglobulins
or their derivatives at sites of election such as renal glomeruli
• Accumulation of lymphocytes and plasma cells at sites of lesion
• Benefit from corticosteroid or immuno suppresive therapy.
![Page 8: DEFINITION : Any structural or functional damage produced by the action of immunologically competent cells or antibodies against the normal cells is known](https://reader036.vdocuments.us/reader036/viewer/2022062804/5697bf831a28abf838c861d8/html5/thumbnails/8.jpg)
• Occurrence of more than one type of autoimmune lesion in an individual
• A genetic predisposition towards autoimmunity
• Higher incidence among females
• Chronicity, usually non reversible
![Page 9: DEFINITION : Any structural or functional damage produced by the action of immunologically competent cells or antibodies against the normal cells is known](https://reader036.vdocuments.us/reader036/viewer/2022062804/5697bf831a28abf838c861d8/html5/thumbnails/9.jpg)
• However, mere presence of autoantibodies during course of disease does not prove their causative role.
• Autoantibody formation may be result of tissue injury and the antibody may help in promoting immune elimination of damaged cells or tissue elements.
• A typical example is lepromatous leprosy.
![Page 10: DEFINITION : Any structural or functional damage produced by the action of immunologically competent cells or antibodies against the normal cells is known](https://reader036.vdocuments.us/reader036/viewer/2022062804/5697bf831a28abf838c861d8/html5/thumbnails/10.jpg)
• The relative importance of humoral and cellular immunity in autoimmune disease is not known.
![Page 11: DEFINITION : Any structural or functional damage produced by the action of immunologically competent cells or antibodies against the normal cells is known](https://reader036.vdocuments.us/reader036/viewer/2022062804/5697bf831a28abf838c861d8/html5/thumbnails/11.jpg)
MECHANISMS OF
AUTOIMMUNITY
![Page 12: DEFINITION : Any structural or functional damage produced by the action of immunologically competent cells or antibodies against the normal cells is known](https://reader036.vdocuments.us/reader036/viewer/2022062804/5697bf831a28abf838c861d8/html5/thumbnails/12.jpg)
NEOANTIGENS
• PHYSICAL : irradiation, photosensitivity, cold allergy
• CHEMICAL : drugs, chemicals, metals etc.
• BIOLOGICAL : microorganisms - viruses, bacteria
• MUTATIONS
![Page 13: DEFINITION : Any structural or functional damage produced by the action of immunologically competent cells or antibodies against the normal cells is known](https://reader036.vdocuments.us/reader036/viewer/2022062804/5697bf831a28abf838c861d8/html5/thumbnails/13.jpg)
![Page 14: DEFINITION : Any structural or functional damage produced by the action of immunologically competent cells or antibodies against the normal cells is known](https://reader036.vdocuments.us/reader036/viewer/2022062804/5697bf831a28abf838c861d8/html5/thumbnails/14.jpg)
CROSS - REACTING ANTIGEN THEORY
![Page 15: DEFINITION : Any structural or functional damage produced by the action of immunologically competent cells or antibodies against the normal cells is known](https://reader036.vdocuments.us/reader036/viewer/2022062804/5697bf831a28abf838c861d8/html5/thumbnails/15.jpg)
MOLECULAR MIMICRY THEORY
• EX: Arithritogenic shigella flexneri – HLA-B27
Mycobacterium tuberculosis - joint memb
coxsackie B - Myocardium
![Page 16: DEFINITION : Any structural or functional damage produced by the action of immunologically competent cells or antibodies against the normal cells is known](https://reader036.vdocuments.us/reader036/viewer/2022062804/5697bf831a28abf838c861d8/html5/thumbnails/16.jpg)
POLYCLONAL B CELL ACTIVATION
![Page 17: DEFINITION : Any structural or functional damage produced by the action of immunologically competent cells or antibodies against the normal cells is known](https://reader036.vdocuments.us/reader036/viewer/2022062804/5697bf831a28abf838c861d8/html5/thumbnails/17.jpg)
BRAEKDOWN OF IMMUNOLOGICAL
HOMEOSTASIS
![Page 18: DEFINITION : Any structural or functional damage produced by the action of immunologically competent cells or antibodies against the normal cells is known](https://reader036.vdocuments.us/reader036/viewer/2022062804/5697bf831a28abf838c861d8/html5/thumbnails/18.jpg)
ENHANCED HELPER T CELLS AND DECREASED SUPPRESSOR T CELL FUNCTIONS
![Page 19: DEFINITION : Any structural or functional damage produced by the action of immunologically competent cells or antibodies against the normal cells is known](https://reader036.vdocuments.us/reader036/viewer/2022062804/5697bf831a28abf838c861d8/html5/thumbnails/19.jpg)
SEQUESTRATED ANTIGENS
![Page 20: DEFINITION : Any structural or functional damage produced by the action of immunologically competent cells or antibodies against the normal cells is known](https://reader036.vdocuments.us/reader036/viewer/2022062804/5697bf831a28abf838c861d8/html5/thumbnails/20.jpg)
DEFECTS IN IDIOTYPE - ANTI-IDIOTYPE
NETWORK