L22: Clinical Autoimmunity Flashcards
What is autoimmunity
The failure of self tolerance
What are the general features of the failure of self tolerance
B cell and T cell reactivity to self antigens
Frequent autoantibodies produced
What are the 2 types of tolerance
Central
Peripheral
What does the central T cell tolerance occur
In the thymus
Where does B cell central tolerance occur
Bone marrow
What occurs in central tolerance for t cels
Positive selection in the cortex
Negative selection in the medulla
What occurs in the peripheral tolerance for T cell
Ignorance
Anergy
Cell deaths
Suppression
How is B cell peripheral cell tolerance occur
Lack of T cell help
When can we get a loss of ignorance in T cell tolerance
Sympathetic ophthalmia
How does sympathetic ophthalmia lead to loss of ignorance
You get a penetrating injury and a immune response occurs and areas that are usually ignored via ignorance become known in the immune system
How do we get anergy and cell death occuring
When a dendritic cell presents a self antigen to a T cell if if recognises the self antigen the cell will undergo anergy and death
How do we get a loss of anergy and cell death
When the T cell recognises the self antigen on the dendritic cell and becomes activated
How do we get a loss of suppression in T cell peripheral tolerance
Due to loss of t reg function
When there is a loss of T cell tolerance what happens to the B cells
They produce autoantibodies
How do autoantibodies cause disease
Complement dependent lysis Opsonisation Immune complex Receptor blockade Receptor stimulation
What is hashimoto disease
When autoantibodies bind to TSH receptor, thyroid peroxidase and thyroglobulin to block the action of TSH and decrease thyroid hormone production
What are the symptoms of hashimoto disease
Weight gain Constipation Hair thinning Neck swelling Hoarse voice Fatigue
What is Graves’ disease
Autoantibodies stimulate the thyroid by binding to TSH receptors and acting like TSH
What are the symptoms of Graves’ disease
Weight loss Heart beat Diarrhoea Anxiety Eye prominence
What is goodpastures syndrome
Specific antibodies to the capillary basements membrane to the glomerulus and lung alveoli
What are the symptoms of goodpastures syndrome
Fatigue Increasing pallor Blood urine Peripheral oedema Oliguria
Name a systemic autoimmune disease
Rheumatoid arthritis
What are the symptoms of RA
Very stiff hands
Joints in hands, wrist and knees symmetrically swollen
If the RA is systemic disease what other parts of the body can it go onto affect
Nodules
Eye inflammation
Lungs: fibrosis
Vasculitis: blood vessel inflammation
What is autoimmune disease often associated with
Genetic predisposition
