13 - Hypersensitivity and Autoimmunity

Question 1

Goodpasture syndrome, type of reaction and antigen. Tissues involved.

Answer 1

• type IV collagen basement membrane
• type II hypersensibility
• kidney and lung

Question 2

No complement nor antibodies participating in hypersensibility reaction. What type is? Diseases exception because autoantibodies are used as clinical markers no as pathogenesis?

Answer 2

Type IV - delayed type hypersensitivity

Hashimoto thyroiditis, rheumatoid arthritis

Question 3

Tuberculin test is what type of hypersensitivity

Answer 3

Type IV hypersensitivity - cell mediated

Question 4

What type of response is generated against poison ivy? What would you use to treat them if you could use a citokine?

Answer 4

Type IV - delayed-type hypersensitivity response - cell mediated
IL-10 ▶️ (-) TH1 response

Question 5

What conditions may occur if an Antigen is added to pre-existing antibody and immune complexes are filtered out the circulation in the small vasculature. Type of response?

Answer 5

Arthus reaction and serum sickness ▶️ precipitation of those complexes in small vasculature ▶️ (+) complement ▶️ tissue damage
Type III hypersensitivity reaction

Question 6

Type of response of passive cutaneous anaphylaxis. Clinical use.

Answer 6

Type I hypersensitivity reaction

Diagnostic technic ▶️ passive transfer of serum

Question 7

Why does the type III hypersensitivity reaction tend to be systemic?

Answer 7

Immune complexes overwhelm the mononuclear phagocyte system to clean them

Question 8

Election test to perform in a newborn from HIV-infected mother

Answer 8

• PCR for HIV DNA
• Viral culture

*because IgG against virus from mother is transported across the placenta, therefore you will not able to know the right source of that IgG - it would produce a false positive ELISA and WB until 1 year old infant.