Type III Hypersensitivity

Question 1

“big picture” about T(III)HS

Answer 1

“immune complex diseases”

circulating abs bind to circulating ags, which deposit into vessels, leading to inflammation in the vessel walls

vasculitis

Question 2

“immune complexes”

Answer 2

circulating Abs + Ags –> immune complex

deposits in vascular membranes

Complement AND Fc mediated recruitment activation of leukocytes

Question 3

What kind of damage do we expect from immune complexes?

Answer 3

inflammation followed by ischemic damage to tissue

Question 4

What is the major activator in T(III)HS?

Answer 4

classical activation

Question 5

T(III)HS: nephritis, arthritis, vasculitis

Answer 5

Systemic lupus erythematosus

targets include DNA, nucleoproteins, others

Question 6

T(III)HS: vasculitis only

Answer 6

polyarteritis nodosa

targets include: microbial antigens (hep B virus surface antigens)

Question 7

T(III)HS: nephritis only

Answer 7

Post-streptococcal glomerulonephritis

streptococcal cell wall antigens

Question 8

T(III)HS: systemic vasculitis, nephritis, arthritis

Answer 8

Serum sickness

targets various protein antigens

Question 9

T(III)HS: cutaneous vasculitis

Answer 9

arthus reaction

various protein antigens

Question 10

Where are the immune complexes detected?

Answer 10

in the blood or in the tissues that are the sites of injury

Question 11

in all the disorders, injury is caused by

Answer 11

complement-mediated and Fc-mediated inflammation