Immune System - Autoimmune Diseases

What does autoimmunity mean?

Failure of the immune system to recognize "self" -> body attacks itself

How are autoimmune diseases classified?

Systemic and organ-specific

What are examples of systemic autoimmune diseases?

SLE and RA

What are examples of organ-specific autoimmune diseases?

Type 1 diabetes mellitus and myasthenia gravis

What are systemic autoimmune diseases?

General defect in immune regulation, excessive activity of T and B cells, broad immune response involving many organs and tissues

What are the causes of SLE (Systemic Lupus Erythematosus)?

Antibodies against self-antigens (DNA, platelets, cell surface proteins, or IgG), anti-nuclear antibodies (ANA), antibodies against RBCs, immune complex deposition in organs, and kidney damage

What are the treatments for SLE?

Pain relievers and non-specific immunosuppressants; immunotherapy -> Belimumab (Benlysta) -> is an IgG1-lambda monoclonal antibody which reduces activity of B-cell mediated immunity

What are the causes of RA (Rheumatoid Arthritis)?

The innate and adaptive immune systems attack the synovial membrane that surrounds our joints

What are the treatments for RA?

Anti CD20 B-cell inhibitor - Rituximab (Rituxan)

T-cell activation inhibitor - Abatacept (Orencia)

IL-6 receptor block - Tocilzumab (Acetemra)’

IL-1 receptor antagonist - Anakinra (Kineret)

TNF-alpha inhibitors - Adalimumab (Humira) + Certolizumab pegol (Cimzia)

What happens in Type 1 DM (Insulin-dependent Diabetes Mellitus)?

In the pancreas, beta cells produce insulin however, the immune system is attacked and destroys these beta cells leading to no insulin and high blood glucose

What is the treatment for Type 1 DM?

Supply insulin

What happens in Myasthenia Gravis?

Auto-antibodies go against acetylcholine receptors which prevents acetylcholine from binding to its receptors and activates complement, destroying the receptors -> progressive weakening of skeletal muscles

What is the treatment for Myasthenia Gravis?

Cholinesterase inhibitors, corticosteroids, immunosuppressants