Definition: Damage to host tissue caused by an immune response which cannot be directly attributed to
an infection process
Introduction
● Organ specific or systemic
● Approximately 40 [known] diseases, affects 5% of population
● Autoantibody generation (inappropriate TH2 response, humoral) or mononuclear cell invasion
(inappropriate TH1 response, cell mediated)
Proposed Mechanisms
● Cause of loss of self-tolerance is unknown. More research needed for identification of target self
antigens and why autoantibodies can also be found in healthy individuals
● Cryptic antigen response
○ Antigen causing autoimmune response is usually hidden until cell bursts/damaged etc.
● Sequestered antigen release
○ viral/physical damage causes cell to burst open and release contents → an
otherwise concealed peptide is exposed
● bacterial/viral mimicry & cross reaction
○ bacterial/viral antigen recognised by the immune system and creates antibodies. If
recognised antigen is very similar in shape to a self antigen then can cause an autoimmune
response
● Undiscovered pathogen causing immune
Cytoplasmic islet cell antibody (ICA)
response
● Abnormal immunoregulation
○ Fault with T cells
HUMORAL
Anti-insulin antibody prevents insulin
● Polyclonal activator production
○ Superantigens bind to non-matching
binding site
● Anti-idiopathic networks Anti-GAD antibody destroys any insulin
produced
○ Antibodies bind to one another to
activate one another. Over reaction?
TH1 cytokine profile
● Latent viral infection
○ If virus stays dormant in cell for too lo ,ng
it may change self antigen binding site(s) Mononuclear cell infiltration
CELLULAR
(macrophages) decrease of antibody
activity
Multifactorial Influences
● Interaction of many risk factors
● Specific interactions and environmental factors Tc and/or NK cells causes cell apoptosis
Genetic Predisposition
● Could link to many chromosomal loci → Specific targeting of B cells induction of cell
more susceptible or resistant? apoptosis
● MHC class I and II haplotypes inherited and can
determine relative risk
The benefits of buying summaries with Stuvia:
Guaranteed quality through customer reviews
Stuvia customers have reviewed more than 700,000 summaries. This how you know that you are buying the best documents.
Quick and easy check-out
You can quickly pay through credit card or Stuvia-credit for the summaries. There is no membership needed.
Focus on what matters
Your fellow students write the study notes themselves, which is why the documents are always reliable and up-to-date. This ensures you quickly get to the core!
Frequently asked questions
What do I get when I buy this document?
You get a PDF, available immediately after your purchase. The purchased document is accessible anytime, anywhere and indefinitely through your profile.
Satisfaction guarantee: how does it work?
Our satisfaction guarantee ensures that you always find a study document that suits you well. You fill out a form, and our customer service team takes care of the rest.
Who am I buying these notes from?
Stuvia is a marketplace, so you are not buying this document from us, but from seller kayrose. Stuvia facilitates payment to the seller.
Will I be stuck with a subscription?
No, you only buy these notes for $3.90. You're not tied to anything after your purchase.
