Mucosal Immunity 2

Question 1

What is the main site for oral tolerance induction?

Answer 1

Mesenteric lymph nodes

Question 2

Oral tolerance?

Answer 2

Avoidance of an immune response to food

Question 3

Inferior rectal nodes drain into?

Answer 3

Inguinal nodes

Question 4

What is route of B cells and T cells into mesenteric lymph nodes?

Answer 4

They will be arriving via high endothelial venules from peyers pathches via MLN to thoracic duct

Question 5

Damage to liver can cause?

Answer 5

Leakage of LPS causing low grade fever, bypass through splenic vein

Question 6

Intraepithelial lymphocytes are located?

Answer 6

In basolateral portion of the epithelium

Question 7

What are features of intraepithelial lymphocytes?

Answer 7

Irregular shape, long extensions in close contact with neighbouring epithelial cells.
Mixed with eosinophils which can make up to 12% in intraepithelial cell preparations

Question 8

Tissue resident memory T cells?

Answer 8

TCR alpha beta CD8 alpha beta
TCR alpha beta CD8 alpha alpha
TCR alpha beta CD4

Question 9

What binds to stress receptors on the damaged gut epithelial cells MIC-A MIC-B?

Answer 9

NKG2D- Tcells that carry NK cell receptors

CD8 alpha alpha

And kill by apoptosis

Question 10

What do intraepithelial CD8 T cells produce?

Answer 10

IFN gamma and are important in killing infected epithelial cells

Question 11

Bacteria in the gut lumen induce?

Answer 11

IL-17 producing T helper cells

Question 12

What do IL 17 and 22 do?

Answer 12

Interact with receptors on epithelial cells to regulate production of mucins or defensins.

Question 13

Classic Th17 cells produce?

Answer 13

Il 17 and IFN gamma and are cytotoxic, may kill endothelial cells

Question 14

T regs are produced in response to?

Answer 14

Presence of retinoids acid and TGF B, produced by dendritic cells

Question 15

Treg’s produce?

Answer 15

Il 10, helpful in tolerance

Question 16

Immune exclusion?

Answer 16

Immune system labels antigens so they don’t cause an immune response, done by IgA

Question 17

IgA is?

Answer 17

Dimeric coupled by J chain

Question 18

What enables trans-endothelial transport of dimeric IgA and igM?

Answer 18

Poly-ig receptor

Question 19

Why do TLRs on basolateral surface not trigger inflammation?

Answer 19

Better to tighten junctions than cause inflammation

Question 20

Homing?

Answer 20

T cells and B cells have to return to the effector sites adjoining the induction sites where they are primed.

Question 21

Homing happens through?

Answer 21

Imprinted on cells by regulation of the gut associated lymphoid tissues, receptors on venules

Adhesion molecules on lymphocytes and receptor molecules on endothelial cells

Question 22

Dendritic cells are induced to express?

Answer 22

Retinaldehyde dehydrogenase, which converts vitamin A to retinoic acid.

Question 23

What does retinoic acid do?

Answer 23

Upregulation of adhesion molecules on lymphocytes in mesenteric lymph nodes or PP

So they express CCR9 and a4/B7 the ligand for CCl25

Question 24

Where is all the lymph collected?

Answer 24

Cisterna chyli

Question 25

Which are immune cells in liver sinuses, important in maintaining food tolerance?

Answer 25

Kuppfer cells

Question 26

Intraepithelial lymphocytes include?

Answer 26

Tissue resident memory T cells

Innate like and innate lymphocytes:
Mucosa associated invariant T cells 
NK T cells
Gamma delta T cells
NK cells

Question 27

Where are dendritic cells?

Answer 27

Lamina propria

Question 28

Poly Ig receptor binds to?

Answer 28

J chain