11: Autoimmune Disease Flashcards
Autoimmune disease
Immune reaction directed against a self-Ag that is responsible for a pathological condition
Central and peripheral tolerance
Central: learned prior to release from generative lymphoid organs
Peripheral: ongoing regulation in peripheral tissues
T cell vs B cell receptor editing
T cells in thymus: if they cross react with self Ag -> apoptosis
B cells in bone marrow: if they cross react with self Ag -> receptor editing or apoptosis
Two mechanisms of peripheral tolerance
Treg cell suppression + anergy
Anergy in T cells
T cells have inhibitory receptors CTLA and PD-1 that inhibit immune interactions
Conditions associated with molecular mimicry and epitope spreading
Molecular mimicry: rheumatic heart disease
Epitope spreading: oral lichen planus
Findings of oral lichen planus
Keratosis and blistering in mouth
Three diseases that show ANA (anti-nuclear Abs)
lupus (all three discussed), sjogren’s, systemic sclerosis
describe the utility of ANA
Its a nonspecific test, so its presence can prompt more specific testing, and its absence can help rule out certain conditions
Specific testing for lupus, sjogren’s, and systemic sclerosis
Lupus: anti DS DSA
Sjogren’s: anti Ro/SS-A, anti-La/SS-B
Systemic sclerosis: anti DNA topoisomerase
Common sense takeaways from the six types of lupus nephritis
Minimal first, sclerosing (end-stage) is last
Libman-Sacks endocarditis
Verrucous (warty) valve depositions of fibrin, can embolize
L-E cell and what pts they can be seen in
A neutrophil/macrophage that ingests the nucleus of a damaged cell, can be seen in body fluids of pts with lupus
Test to evaluate dryness of eyes in Sjogren’s
Schirmer’s test
