Exam Questions

Why does the GI tract represent a unique challenge for our immune system?

(a) It needs to mount antigen responses but also be tolerant against food

(b) It has a large surface area

(c) It has other functions besides mounting immune responses (e.g. nutrient absorption)

(d) It needs to protect from pathogens but also be in symbiosis with the microbiota

(e) The gut epithelium renews itself every few days

(f) All of the above

Which of the following are not gut associated lymphoid tissues?

(a) Mesenteric lymph nodes

(b) The Peyer’s patches

(c) Lamina propria

(d) Isolated lymphoid follicles

(e) Epithelium

(f) Crypts

What are some of the main immunological differences between the intraepithelial (IE) and lamina propria (LP) compartments of the gut?

(a) The IE is an effector site, whereas the LP is an inductive site

(b) The IE contains only specialized lymphocytes with site-specific functional properties

(c) The IE belongs to the mucosa, whereas the LP is in the sub-mucosa

(d) The numerous epithelial cells of the IE compartment make it an important innate immune site

(e) Only the stromal cells in the IE compartment are immunologically active

(f) The LP contains numerous and diverse immune cell types unlike the IE compartment

Which of the following are major functions of migratory cDC1 in the intestine?

(a) Priming of intestinal Th17 responses

(b) Priming of intestinal Th1 responses

(c) Migration from the epithelium to the lamina propria to present antigen

(d) Cross presentation of epithelial derived antigen to CD8+ T cells

(e) Help B cells produce IgA in the isolated lymphoid follicles

(f) Migration to the mesenteric lymph node to prime Th2 responses

After a gut infection recently primed T cells know to go the gut because:

(a) DCs will present antigen in the draining mesenteric lymph nodes

(b) DCs will take antigen from lumen and present to lamina propria T cells

(c) During priming in mesenteric lymph nodes DCs will give gut homing signals to T cells

(d) T cells primed in the Peyer’s patches cross through M cells and end up in the lamina propria

(e) When primed in GALT they will express CCR9 and α4b7

(f) They are specific for the microbiota