Immuno 1

Question 1

This image shows an antigen-presenting cell activating a CD4 Th cell. Identify (A-E), which all activate the Th cell.

A mutation in which receptor would result in Hyper-IgM?

Answer 1

(A) MHC II;

(B) T-cell receptor;

(C) CD4;

(D) B7 Cd80/86

(E) CD28

Question 2

Which complement fragments degranulate mast cells

Answer 2

C3a, C5a

Question 3

How is the classic pathway activated?

How is the alternative pathway of the complement system activated?

How is the lectin pathway of the complement system activated?

Answer 3

By IgG/IgM antigen-antibody complexes (GM makes classic cars)

Microbial surface molecules

Question 4

How is the membrane attack complex (MAC) is formed? What organisms does the MAC complex protect us from?

Answer 4

C5 is cleaved to c5a and c5b

C5b joins with C6-9

Question 5

How is the lectin pathway of the complement system activated?

Answer 5

Mannose or other sugars found on microbial surface

Question 6

What are the two primary opsonins

Answer 6

Opsonization and clearance of immune complex;

C3b binds bacteria

Opsonization and clearance of immune complex;

IgG

Question 7

A pt has hives, diaphoresis, & shortness of breath after eating peanuts. Which complement proteins are involved?

Answer 7

C3a, C4a, C5a—anaphylaxis

Question 8

How is C3 convertase different when converted from the classical vs the other 2 pathways

Answer 8

Classic–> C3b-BB

Other–>C4b2b

Question 9

What 2 components prevent complement activation on self cells?

Answer 9

Decay-accelerating factor (DAF, also known as CD55) & C1 esterase inhibitors