2.1 Immuno

Question 0

IgA subtypes

Answer 0

IgA1: large, can bind multiple sites on pathogen
IgA2: small, resistant to proteolysis (only place more common is colon)

Question 1

Gut homing

Answer 1

Occurs in T cells
a4:b7 binds MAdCAM-1
CCR9 binds CCL25
aE:b7 binds E cadherin

Question 2

NOD protein

Answer 2

Like TLRs except they’re in cytoplasm, not in a vesicle

Both activate NFkB

Question 3

CD4 response to helminth

Answer 3

Th2 acts to expel parasite

• IL13 incr mucus and turnover
• IL5 activates eosinophils to make MBP which kill parasite
• IL4 activates B cell to produce IgE
• IL3&9 recruit mast cells

Th1 damages host

• activates macrophages (tissue damage)
• IFNgamma activates B cells to produce IgG to fix complement (won’t work)

Question 4

In infections, what 2 cellular molecules increase

Answer 4

Effector T cells

Antibodies

Question 5

Protective immunity is characterized by

Answer 5

Only having antibodies (prevents reinfection)

Question 6

Difference in immunoglobulins in primary vs secondary response

Answer 6

Primary: Ig GAME
Secondary: Ig GAE (no M!!)

Question 7

Central memory T cell vs Effector memory T cell

Answer 7

Central memory T cell has CCR7

Effector memory T cells don’t have CCR7 (instead have CCR3&5)

Question 8

Characteristic receptor of memory T cells

Answer 8

CD45RO

Question 9

Central memory T cells vs effector memory T cells in terms of L selectin

Answer 9

Central memory T cells are L selectin positive

Effector memory T cells are L selectin negative

Question 10

Where do central and effector memory T cells circulate?

Answer 10

Central: lymphoid organs
Effector: non lymphoid tissues

Question 11

Mechanism that prevents naive B cells from being activated in a secondary immune response

Also explain why this happens

Answer 11

IgG bound to Ag binds to naive B cell and sends an inhibitory signal

Don’t want to make low affinity IgM when you can make high affinity IgA,E,G from memory B cells

Question 12

Th2 secretes IL13 to

Answer 12

Increase mucous and turnover

Question 13

Th2 releases IL5 to

Answer 13

Activate eosinophils to produce MBP to kill parasite

Question 14

Th2 releases IL4 to

Answer 14

Cause B cells to release IgE

Question 15

Th2 releases IL3&9 to

Answer 15

Activate mast cells

Question 16

2 effects of Th1 in parasite infections

Answer 16

Activate macrophage (causes cell damage)

Activate B cells to produce IgG2a which fixes complement but doesn’t work against large parasite