Mucosal Immunity

Question 1

Does the epithelium have tight junction?

Answer 1

Yes

Question 2

What does MALT means

Answer 2

Mucosa associate lymphoid tissue

Question 3

Locally homed T and B cells recirculate where?

Answer 3

Where they first encountered antigen

Question 4

Weldeyer’s ring is an example of what site

Answer 4

Effector

Question 5

There are two types of lymphoid structures what are they (sample environmeny Peyer’s patches)

Answer 5

There are scattered lymphoid cells (sample environment) (intraepithelial cells) and also there are organised lymphoid tissues (like Peyer’s patches).

Question 6

What type of Ig is secreted in large amounts post antigen recognition?

Answer 6

IgA

Question 7

AMP function in mucosal immunity

Answer 7

AMP constantly binds and neutralises bacteria

Question 8

What regulates the mucosal immune system (type of immune cells (2))

Answer 8

DCs and Macrophages which are tolergenic

Question 9

What type of highly mobile epithelial cell constantly surveys the epithelium

Answer 9

Intestine epithelial cells (IEL)

Question 10

Epithelium is quickly self-renewing, stem cell differentiation can lead to:

Answer 10

• Enterocytes/colonocytes: absorptive functions, AMPs production
• Paneth cells: Antimicrobial peptide productions (AMPs)
• Goblet cells: mucus secretion
• Enteroendocrine cells: Neurohumoral secretion.

Question 11

Paneth cells produce what which forms pores

Answer 11

Alpha beta defensins

Question 12

Sebocytes produce what antimicrobial structure

Answer 12

Histones

Question 13

What is the dominant class of Ab on mucosal surfaces

Answer 13

IgA

Question 14

What IgA type is in lung

Answer 14

IgA1

Question 15

What class of IgA is in the colon

Answer 15

IgA2

Question 16

What is the major function of secreting IgA.
I_______ e_________

Answer 16

Immune exclusion

Question 17

IgA abosrbs through mucus layer thorugh interactions with what

Answer 17

Carbohydrate moieties

Question 18

What does IgA not activate, also what enzyme are they resistant to

Answer 18

complement classical pathway, don’t promote inflammation, protease resistant.

Question 19

What type of process is used to produce IgA

Answer 19

Class swithcing

Question 20

Gut IELs are recognised and lead to the elimination in what epithelial cells

Answer 20

Ones that express an abnormal phenotype resulting from stress or infection

Question 21

Inappropiate or excessive activation of IELs gives rise to what type of disease

Answer 21

Coeliac

Question 22

Innate lymphoid cells are the counterpart of what cell types

Answer 22

CD4+ cells

Question 23

Innate lymhoid cells come from a precursour that also diverts to T/B cells. Is this true or false

Answer 23

True

Question 24

What receptor don’t innate lymphoid cells have

Answer 24

TCR

Question 25

ILCs are poised to secrete what

Answer 25

poised to secrete cytokines that respond swiftly to pathogenic tissue damage

Question 26

In helminth infection what ILCs are produced and what do they produce, cause to cell and increase production of

Answer 26

Example is helminth infection is that ILC2s will produce cytokine IL-13, cell contraction, mucus production to heal the lining.

Question 27

Distinct populations of DCs sample the mucosal compartment. They generate what type of T cell and how do they home T/B cells

Answer 27

Anti-inflamatory, generate Tregs, imprint homing via retionic acid

Question 28

Gut homing lymphocytes is via what? And where is it present

Answer 28

MadCAM ;is on vasculature of all mucosa

Question 29

M cells constantly do what?

Answer 29

Survery the environment and pass onto DCs

Question 30

Host commebsal interactions are required for what vitamin or what type of acid

Answer 30

vitamin K, short chained fatty acids

Question 31

Antibiotic overuse leads to what infection

Answer 31

C. diff

Question 32

What can't you have an overt inflammatory response to? In gut

Answer 32

Commensals

Question 33

Commensals down regulate what pathways. How, in two ways?

Answer 33

Inflammatory, via MYD88. Constantly trigger PRRs, decreasing their senstivity PPAR-gamma induced in response to microbiota LPS diverys NF-kB from nucleus

Question 34

What cell type does Shigella invade through

Answer 34

M cells

Question 35

Toxins and other factors faciliate invasion by pathogens: Give three examples

Answer 35

Toxins and other factors facilitate invasion by pathogens. Shiga toxin inhibits translation. C. diff toxin A inactivates GTPase Rotavirus NSP4 disrupts tight junction.

Question 36

Th2 responses are to h___ infections, and may be triggered by T____ or IL____

Answer 36

Somehow trigger a type II response: trigger unknown, maybe TSLP or IL-33. Type II responses lead to expulsion and wound repair.

Question 37

Give three examples of aberrant mucosal immunity

Answer 37

Crohn’s (NOD2, Atg16L1) sustained microbial-induced inflammatory Coeliac HLA-DQ2 (binds gliadin) Disturbance in microbiome-antibiotics C. difficile infection