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
