Autoimmunity Flashcards
What is autoimmunity?
A condition in which an humoral or cell mediated immune response is created against components of the body’s own tissues.
A misdirected immune response- body atacks itself.
What is needed to induce an autoimmune response?
A genetic predisposition to the autoimmune disease.
An immune trigger- not really well known. Can cause problems for treatments. Better treatment given if you can determine what is going on. Treatment can dampen down the immune response.
An autoantigen- this is the parts of self tissues that are attacked.
What conditions are evidence for loss of self tolerance?
Primary immunodeficiency.
APECED- autoimmune polyendocrinopathy, candidiasis and ectodermal dystrophy. Autosomal recessive. AIRE autoimmune regulator, can’t remove autoimmune T cell in the thymus- failure of negative selection. Present with adrenal autoimmunity.
IPEX- Immune dysregulation, polyendocrinopathy, X linked disease. FoxP3- failure to educate regulatory T cells.
What is the genetic basis of autoimmunity?
Genetic predisposition:
-Increased incidence in monozygotic twins.
Identification of disease-associated genes by breeding and genomic appraoches.
Multiple genes are associated with autoimmunity, not a single mutation.
MHC genes have a major genetic association to autoimmunity. Disease alleles may be found in healthy people.
Non MHC genes:
Many loci have been identified. Mutations in complement genes predispose to lupus.
What is the genetic basis of autoimmunity?
Genetic predisposition:
-Increased incidence in monozygotic twins.
Identification of disease-associated genes by breeding and genomic appraoches.
Multiple genes are associated with autoimmunity, not a single mutation.
MHC genes have a major genetic association to autoimmunity. Disease alleles may be found in healthy people. This is the strongest genetic factor for susceptibility.
Non MHC genes:
Many loci have been identified. Mutations in complement genes predispose to lupus.
What is the main environmental factor that can trigger autoimmune diseases?
Infectious organisms. Although diet and chemicals may play a part also.
