Pathogenesis of Autoimmune Disease Flashcards
Define Rheumatoid Arthritis.
Chronic autoimmune (more than 6 weeks) disease characterised by pain, stiffness and symmetrical synovitis of synovial joints Chronic (more than 6 weeks) joint inflammation that can result in joint damage Site of inflammation is the synovium (synovial membrane) hence called synovitis
What is the site of inflammation in rheumatoid arthritis?
Synovium
What are the two main autoantibodies that are associated with rheumatoid arthritis?
Rheumatoid factor
Anti-cyclic citrullinated peptide antibody
Other than at joints, where else is synovium found?
synovial membrane around tendons (tenosynovium)
Define Ankylosing Spondylitis.
Chronic spinal inflammation that can result in fusion and deformity
What is the site of inflammation in ankylosing spondylitis?
Entheses – where a ligament or a tendon inserts into bone
What family of diseases is ankylosing spondylitis a part of?
Seronegative spondyloarthropathies
Which other diseases fall into this family of diseases?
Reiter’s syndrome and reactive arthritis
Psoriatic arthritis
Enteropathic synovitis
Define Systemic Lupus Erythematosus (SLE).
Chronic tissue inflammation in the presence of antibodies directed at self-antigens
NOTE: it is inflammation of sterile tissue
Lupus causes multi-site inflammation but state some sites that are particularly badly affected.
Joints, Skin and Kidneys
What are the two autoantibodies that are associated with lupus?
Anti-nuclear antibodies
Anti-double stranded DNA antibodies
What family of diseases is lupus a part of?
Connective tissue diseases
What other diseases are part of this family?
Systemic sclerosis (diffuse and localised)
Polymyositis/Dermatomyositis
Sjogren’s syndrome
Mixed connective tissue disease
What is Sjogren’s syndrome?
An autoimmune disease that targets the exocrine glands (e.g. lacrimal glands)
What are the MHC associations of rheumatoid arthritis, ankylosing spondylitis and SLE?
Rheumatoid arthritis – HLA-DR4 (MHC 2)
SLE –HLA-DR3 (MHC 2)
Ankylosing spondylitis – HLA-B27 (MHC 1)