Deck 13: Mucosal Immunity and the Microbiome

Question 1

Which of the following is NOT a normal part of commensal microbiota?

A)Bacteria
B)Viruses
C)Nematodes
D)Fungi
E)Protozoa

Answer 1

E

Question 2

Which part of our body is the BEST example of a barrier organ?

A)Skin
B)Liver
C)Kidneys
D)Lungs
E)Spleen

Answer 2

A

Question 3

What mechanism is NOT used by epithelial cells to prevent the invasion of barrier tissues?

A)Secretion of antimicrobial peptides.
B)Phagocytosis of microbes.
C)Production of mucus layer.
D)Use of beating cilia.
E)All of the answers are correct.

Answer 3

B

Question 4

Peyer's patches and isolated lymphoid follicles are components of

A)mucus.
B)GALT.
C)germinal centers.
D)stomach lining.
E)bronchial passages.

Question 5

Which of the following is a tolerogenic cytokine?

A)TGF- ?
B)IL-1
C)IL-10
D)Both TGF- ? and IL-1
E)Both TGF- ? and IL-10

Question 6

MOST immune cells in the gut can be found in the

A)mucosa.
B)submucosa.
C)lamina propria.
D)villi.
E)crypts.

Question 7

What is the meaning of the gut epithelial cells being "polarized"?

A)They have distinct apical and basolateral sides.
B)They have many tight junctions.
C)They store positive and negative ions in vesicles.
D)They contain deposits of metals.
E)They diffract wavelengths of light.

Question 8

Which of the following statements is TRUE regarding microfold (M) cells and goblet cells?

A)Only M cells can transport antigens.
B)Only goblet cells can transport antigens.
C)Both M cells and goblet cells move antigens by transcytosis.
D)Neither M cells nor goblet cells move antigens by transcytosis.
E)None of the answers are correct.

Question 9

What would you expect to observe in a suburban Philadelphia patient who was unable to make IgE antibodies?

A)Recurrent norovirus infections
B)Problems with chronic gut inflammation
C)A lack of allergies and asthma
D)Rampant helminthic infection
E)Systemic typhoid fever

Question 10

Which of the following is NOT an antimicrobial molecule secreted into the intestinal lumen?

A)Defensins
B)AMPs
C)REG3 family proteins
D)Enterocyte
E)Lysozyme

Question 11

Retinoic acid is

A)a metabolite of vitamin
B)used to kill pathogens in the gut.
C)released to produce a tolerogenic response.
D)both a metabolite of vitamin A and used to kill pathogens in the gut.
E)both a metabolite of vitamin A and released to produce a tolerogenic response.

Question 12

Compared to the small intestine, the microbiome in the large intestine is

A)identical.
B)less diverse and larger.
C)less diverse and smaller.
D)more diverse and larger.
E)more diverse but equivalent in size.

Question 13

Both celiac disease and ulcerative colitis

A)can lead to tumors.
B)are caused by parasitic nematode infections.
C)are inflammatory diseases that occur in the gut.
D)are disorders of the small intestine.
E)are the result of an overproduction of IL-10.

Question 14

Which of the following is NOT a risk factor for inflammatory bowel disease?

A)NOD2 mutations.
B)Low tryptophan levels.
C)CARD9 mutations.
D)Increased levels of IL-23.
E)All of the answers are risk factors.

Question 15

Which of the following pathogens invades epithelial cells directly?

A)Trichinella
B)Salmonella typhimurium
C)Clostridium difficile
D)Lactobacillus
E)None of the answers directly invades epithelial cells.

Question 16

Which gut disease is MOST closely associated with antigen presentation?

A)IBD
B)IBS
C)Crohn's disease
D)Celiac disease
E)Ulcerative colitis

Question 17

Which of the following is ONLY found in the respiratory tract - and NOT the GI tract?

A)Lamina propria
B)Goblet cells
C)A mucocilliary layer
D)M cells
E)All of the answers are correct.

Question 18

Nasal-associated lymphoid tissue (NALT) MOST closely resembles

A)BALT
B)Peyer's patches
C)Goblet cells
D)Stem cells
E)Lamina propria

Question 19

Which of the following is NOT a response to H.influenza infection?

A)NK cells
B)Type I IFNs
C)TLR pathways
D)Mast cells
E)Alarmins

Question 20

When available, humans are able to receive an intranasal vaccine for which disease?

A)Influenza
B)Measles
C)Mumps
D)Chickenpox
E)Smallpox

Question 21

Which of the following is the name for specialized skin epithelial cells?

A)Enterocyte
B)Keratinocyte
C)Langerhans cell
D)Paneth cell
E)Goblet cell

Question 22

A Langerhans cell is a type of

A)T cell.
B)NK cell.
C)dendritic cell.
D)B cell.
E)epithelial cell.

Question 23

Which of the following diseases would be the BEST candidate for an intranasal vaccine?

A)Norovirus
B)Malaria
C)S.aureus
D)Leishmania
E)Parainfluenza

Question 24

Why is peripheral tolerance critical to barrier immunity?

A)Because it counters inappropriate activation.
B)Because overactivation can lead to chronic inflammation and disease.
C)Because microbes that colonize areas like the skin and intestines are not harmful.
D)Because it both counters inappropriate activation, and overactivation can lead to chronic inflammation and disease.
E)None of the answers explains why peripheral tolerance is critical to barrier immunity.

Question 25

You are an immunologist studying cytokine levels in the gut.Compared to a healthy control, the patient you are studying has the changes listed in the following table.Describe the clinical symptoms that could have contributed to this profile.

Question 26

Provide three benefits of the microbiome inside of our bodies.Explain their significance.

Question 27

There are antibodies present in the gut lumen, despite being produced in the lamina propria (on the other side of the epithelial layer).How is this possible? Explain.

Question 28

What is an enterocyte, and what function does it serve within the immune system? In your response, provide an example of one mechanism that prevents it from reacting to harmless commensal organisms.

Question 29

Which two antibody classes are MOST critical to the maintenance of gut immunity and appropriate tolerance? Explain their significance.

Question 30

What are the four different cell types that work together to maintain immune homeostasis in the gut? Explain the function of each cell type and identify a chronic disease that can develop when these cells are not working properly.

Question 31

Compare and contrast the barrier layers in both the gut and the lungs.

Question 32

When pathogenic microbes invade barrier tissues (such as the lungs or gut), which cytokines are released in response? Explain the effect the cytokines have on the immune response.

Question 33

Explain how parasitic worms and asthma are related, in terms of an immunological response.

Question 34

Provide two examples of commensal organisms providing protection against harmful pathogens.