Autoimmunity

Question 1

PTPN-22

Answer 1

1 single gene mutation in autoimmunity

encodes protein tyrosine phosphatase

mut –> fails to control tyr kinase activity –> excess lymphocyte activity

DM, RA

Question 2

NOD-2

Answer 2

NOD-like receptor, cytoplasmic sensor of microbes in intest epithel (pattern recognition receptors, PAMP/DAMP)

mut –> ineffective sensing –> chronic inflam

Crohn’s

Question 3

epitope spreading

Answer 3

autoimmune disease persists and evolves following infection

disease maintained b/c there is continual activation of new autoreactive T cells recognizing sequestered/cryptic self Ag

Question 4

Pattern & location of ANA in nucleus (SLE)

Answer 4

1. homogenous/diffuse -> chromatin, histones
2. rim/periph -> ds DNA
3. speckled (common, not specific) -> non-DNA nuclear targets
4. nucleolar (few discrete spots) -> RNA

Question 5

cardiolipin

Answer 5

cow heart extract used in syphilis screening

beta2 glycoprotein (antiphospholipid Ab) bind to it

lupus pts may show false + b/c of interference w/ antiphospho. Ab

Question 6

CREST

Answer 6

in limited scleroderma
Calcinosis (subQ calcification)
Raynaud's
Esophageal dysmotility
Sclerodactyly
Telangiectasias

Question 7

ANCA (anti-neutrophil cytoplasmic Ab)

Answer 7

heater group of auto-Ab against enzymes mainly found in 1* granules of neutrophils and in lysosomes of monocytes and in endothelial cells

Question 8

5 main functional classes of cytokines

Answer 8

1. mediate innate immunity
2. regulate lymphocytes
3. activate inflam cells
4. affecting leukocytes mvmt (chemokines)
5. stimulate hematopoiesis