Mucosal Immunology

Question 1

job of mucosal immune system

Answer 1

recognize what is a threat and what is not

Question 2

Why do mucosal surfaces need to be thin and loose?

Answer 2

exchange food, exchange air, sensory activities

Question 3

2 compartments of mucosal surface

Answer 3

structured inductive sites and diffuse effector sites

Question 4

structured inductive sites

Answer 4

peyer’s patches, isolated lymphoid follicles, lymph nodes, tonsils, etc.

Question 5

diffuse effector sites

Answer 5

lamina propria and intraepithelial lymphocytes

Question 6

germinal centers

Answer 6

structures in B cell zone (follicles) where mature B cells are activated, proliferate, and differentiate

Question 7

germinal centers produce _

Answer 7

long-lived Ab secreting plasma cells and memory B cells, which can provide protection against reinfection

Question 8

When do germinal centers develop?

Answer 8

during T-cell dependent antibody responses

Question 9

B cells undergo _ in germinal centers

Answer 9

somatic recombination

Question 10

IgA class switch occurs in _

Answer 10

NALT (nasal)

Question 11

IgA

Answer 11

most abundant isotype; first line of defense

Question 12

serum IgA

Answer 12

downregulates phagocytic ability of PMN leukocytes and pro-inflammatory responses

Question 13

GALT includes _

Answer 13

cryptopatches, ILFs, and peyer’s patches

Question 14

goblet cells

Answer 14

secrete mucus, antimicrobial proteins, and cytokines; can deliver substances to lamina propria

Question 15

intestinal goblet cells secrete _

Answer 15

MUC2

Question 16

respiratory goblet cells secrete _

Answer 16

MUC5

Question 17

resident T cells

Answer 17

non-recirculating; act as memory and can proliferate/secrete cytokines upon stimulation

Question 18

intraepithelial lymphocytes (IELs)

Answer 18

specialized CD8+ T-lymphocytes

Question 19

lamina propria

Answer 19

thin layer of CT that forms part of mucosal surfaces; contains immune cells, blood vessels, lymphatics

Question 20

cryptopatches

Answer 20

beneath the crypts at base of intestinal villi and contain no B/T cells; contain myeloid and ILC3 cells

Question 21

isolated lymphoid follicles

Answer 21

single B cell follicle that often contains a germinal center and a network of fibroblastic stromal cells; critical in establishing an environment for microbial colonization and immune tolerance

Question 22

where are ILFs located?

Answer 22

under M cells

Question 23

peyer’s patches

Answer 23

have numerous B cell follicles with germinal centers, interfollicular regions with T cells zones and DCs

Question 24

lyso-DCs

Answer 24

in peyer’s patches

Question 25

M cells

Answer 25

associated with Peyer’s patches and are important for transcytosis of antigen; mucosal immune surveillance

Question 26

What enhances transcytosis?

Answer 26

IgA

Question 27

paneth cells

Answer 27

epithelial cells containing a high number of eosinophilic granules and help modulate immune homeostasis