Chapter 10 Flashcards

1
Q

Because the mucosae _____, this tissue is predisposed to infection.

a. constitute thin, permeable barriers
b. secrete a continuous layer of mucus
c. generate enzymes and proteoglycans
d. are associated with secretory IgA production
e. are not connected to the lymphatics

A

constitute thin, permeable barriers

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2
Q

Identify which of the following is not a property of secreted mucins.

a. contain glycosylated cysteine residues
b. contain many repetitive sequence motifs
c. constitute a viscous matrix stabilized by disulfide bonds
d. bind to positively charged effector molecules
e. encoded by seven genes in humans
f. expressed in different mucosal tissues

A

contain glycosylated cysteine residues

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3
Q

Unlike secreted mucins, membrane mucins _____.

a. do not trap and kill nearby microorganisms
b. are not cross-linked by disulfide bonds
c. do not possess repetitive domains
d. are not glycosylated
e. are encoded by only one gene in humans

A

are not cross-linked by disulfide bonds

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4
Q

Commensal microorganisms in the gastrointestinal tract facilitate all of the following except _____.

a. compete with pathogenic variants for nutrients and space
b. convert toxic substances to benign derivatives
c. degrade plant fibers to make their nutrients available
d. secrete enzymes required for protein degradation
e. synthesize essential metabolites
f. induce the development of gut-associated lymphoid tissue

A

secrete enzymes required for protein degradation

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5
Q

The large population of microbes that contribute to the gut microbiota and have an important role in food processing are called _____.

a. lamina propria
b. Peyer’s patches
c. microfold cells
d. commensal microorganisms
e. opportunists

A

commensal microorganisms

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6
Q

All of the following are part of Waldeyer’s ring except _____.

a. appendix
b. palatine tonsils
c. lingual tonsils
d. adenoids

A

appendix

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7
Q

Which of the following pairs is mismatched? (Select all that apply.)

a. appendix: large intestine
b. mesenteric lymph nodes: urogenital tract
c. effector compartment: induction of adaptive immune responses
d. adenoids: base of nose
e. villi: small intestine
f. Peyer’s patches: afferent lymphatics

A

b. mesenteric lymph nodes: urogenital tract
c. effector compartment: induction of adaptive immune responses
f. Peyer’s patches: afferent lymphatics

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8
Q

At which anatomical location are Peyer’s patches?

a. stomach
b. small intestine
c. cecum
d. large intestine
e. Waldeyer’s ring

A

small intestine

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9
Q

Laboratory animals reared in gnotobiotic conditions _____.

a. are fed probiotics to disrupt the composition of their microflora
b. lack normal gut microbiota
c. develop appendicitis
d. have larger secondary lymphoid tissues than do control animals
e. have elevated levels of SIgA in the gut lumen

A

lack normal gut microbiota

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10
Q

_____ microorganisms are microbes that colonize mucosal surfaces but under normal circumstances do not cause disease.

a. Opportunistic
b. Commensal
c. Parasitic
d. Mesenteric
e. Pathogenic

A

Commensal

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11
Q

_____ makes up the membranes of connective tissue that help to anchor the gastrointestinal tract and hold it in place.

a. The mesentery
b. Peyer’s patches
c. The lamina propria
d. The subepithelial dome
e. Waldeyer’s ring

A

The mesentery

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12
Q

Waldeyer’s ring includes which of the following? (Select all that apply.)

a. Peyer’s patches
b. lingual tonsils
c. adenoids
d. mesenteric lymph nodes
e. palatine tonsils

A

b. lingual tonsils
c. adenoids
e. palatine tonsils

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13
Q

Which of the following describe M cells in the gut? (Select all that apply.)

a. They derive their name from mucus cells.
b. They are located in the dome of a Peyer’s patch.
c. They deliver antigens and pathogens from the lymphoid tissue to the luminal side of the gut mucosa by transcytosis.
d. They are protected from digestive enzymes by a thick glycocalyx and a layer of mucus.
e. They do not directly participate in antigen processing or presentation

A

b. They are located in the dome of a Peyer’s patch.

e. They do not directly participate in antigen processing or presentation

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14
Q

Mucosae of a healthy intestinal tract _____. (Select all that apply.)

a. have a large number of activated T and B cells
b. harbor T cells bearing a very wide diversity of antigen specificities
c. contain intraepithelial lymphocytes
d. have large numbers of resident neutrophils
e. are populated with both α:β and γ:δ effector T cells

A

a. have a large number of activated T and B cells
c. contain intraepithelial lymphocytes
e. are populated with both α:β and γ:δ effector T cells

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15
Q

Which of the following migrates from non-mucosal tissue to draining lymph nodes to facilitate the induction of adaptive immune responses?

a. dendritic cells
b. macrophages
c. NK cells
d. neutrophils
e. commensal microorganisms

A

dendritic cells

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16
Q

_____ assists in the differentiation of blood-derived monocytes into intestinal macrophages.

a. TGF-β
b. B7
c. IL-12
d. CXCL8
e. CD14

A

TGF-β

17
Q

All of the following are expressed by intestinal epithelial cells except _____.

a. NOD receptors
b. FcαR
c. TLRs
d. MHC class II
e. NFκB

A

FcαR

18
Q

M cells, unlike dendritic cells, _____.

a. do not secrete digestive enzymes into the lumen of the gut
b. are not associated with Peyer’s patches
c. do not facilitate the transport of microbes from the gut lumen to the GALT
d. do not process and present their antigen to naive T cells

A

do not process and present their antigen to naive T cells

19
Q

The significance of MAdCAM-1 on the endothelium of blood vessels is that it binds to _____.

a. the integrin α4β7 on effector lymphocytes homing to mucosal tissues
b. B cells destined to become intraepithelial lymphocytes
c. dendritic cells, and causes the upregulation of antigen processing and presentation
d. the chemokine CCL25, which is secreted by gut epithelia
e. intestinal helminths, and mediates killing of these parasites

A

the integrin α4β7 on effector lymphocytes homing to mucosal tissues

20
Q

In addition to M cells, _____ can capture pathogens directly from the lumen of the gut.

a. intraepithelial lymphocytes
b. plasma cells
c. Paneth cells
d. dendritic cells
e. macrophages

A

dendritic cells

21
Q

Which of the following is not associated with the process by which B cells produce secretory IgA in breast milk?

a. J chain
b. MAdCAM-1
c. αE:β7
d. poly-Ig receptor
e. CCR9
f. transcytosis

A

αE:β7

22
Q

Intracytoplasmic bacteria in enterocytes of the gastrointestinal tract are detected by _____.

a. poly-Ig receptor
b. major basic protein
c. MIC-A and MIC-B
d. NOD proteins
e. receptors for phosphoantigens

A

NOD proteins

23
Q

Secretory IgA binds to pathogens in all of the following locations except the _____.

a. endosomes of an M cell
b. lamina propria
c. lumen of the gut
d. blood
e. Peyer’s patches

A

blood

24
Q

What is the function of the TNF-family cytokine APRIL made by epithelial cells of the colon?

a. elevates rate of M-cell proliferation
b. degrades IgA1
c. mediates isotype switching from IgM to IgA2
d. binds to J chain of dimeric IgA
e. upregulates MAdCAM-1 production

A

mediates isotype switching from IgM to IgA2

25
Q

All of the following soluble factors enhance isotype switching from IgM to IgA in B cells except _____.

a. retinoic acid
b. IL-9
c. TGF-β
d. IL-4
e. IL-10
f. B-cell activating factor (BAFF)
g. APRIL

A

IL-9

26
Q

Which of the following is not an activity associated with secretory IgA and secretory IgM in mucosal secretions?

a. toxin neutralization
b. complement fixation
c. binds to mucin through disulfide bonds
d. restricts commensal microorganisms to gut lumen
e. limits population size of commensal microorganisms

A

complement fixation

27
Q

IgA proteases produced by Streptococcus pneumoniae mediate all of the following effects except _____.

a. separation of Fab and Fc regions
b. interference with FcαR-mediated endocytosis
c. enhanced adherence of Fab-coated bacteria to mucosal epithelium
d. preferential cleavage of IgA2 over IgA1

A

preferential cleavage of IgA2 over IgA1

28
Q

_____ compensates for the absence of secretory IgA in selective IgA deficiency because it can be secreted by mucosal tissues using the same receptor needed for transcytosis.

a. Monomeric IgA
b. IgD
c. IgE
d. IgG
e. IgM

A

IgM

29
Q

The cytokine influencing eosinophil development and function during helminth infections is _____.

a. IL-3
b. IL-9
c. IL-19
d. IL-10
e. IL-5

A

IL-5

30
Q

_____ is the vascular addressin found on endothelial cells of intestinal mucosa that binds to integrins of gut-homing effector lymphocytes.

a. CCL25
b. C-cadherin
c. NOD1
d. MAdCAM-1
e. CCR9

A

MAdCAM-1

31
Q

The dominant immunoglobulin synthesized at mucosal surfaces is _____.

a. IgA
b. IgD
c. IgE
d. IgG
e. IgM

A

IgA

32
Q

If a B cell has been activated by antigen in the mucosa of the respiratory tract, then _____. (Select all that apply.)

a. lactating mothers will provide antigen-specific natural IgA in breast milk
b. secretory IgA will be synthesized in the lamina propria of all mucosae
c. it does not enter the bloodstream but instead remains in the mucosa and differentiates into an effector B cell
d. it will recirculate through all mucosal tissues, including respiratory and gastrointestinal mucosae
e. monomeric IgA is secreted into the lamina propria

A

a. lactating mothers will provide antigen-specific natural IgA in breast milk
b. secretory IgA will be synthesized in the lamina propria of all mucosae
d. it will recirculate through all mucosal tissues, including respiratory and gastrointestinal mucosae

33
Q

In which of the following tissues is IgA2 produced at approximately twice the level of IgA1?

a. spleen
b. mammary glands
c. large intestine
d. gastric mucosa
e. upper small intestine

A

large intestine

34
Q

Secretory IgA is best described as _____.

a. a non-inflammatory immunoglobulin that restricts the passage of antigens across mucosal surfaces
b. a complement-activating immunoglobulin that causes destruction of invasive microflora through the membrane-attack complex
c. an opsonizing antibody that facilitates uptake by M cells through Fc receptors
d. an inflammatory immunoglobulin that stimulates the chemotaxis of neutrophils into mucosal surfaces
e. a monomeric IgA that neutralizes antigen effectively at mucosal surfaces

A

a non-inflammatory immunoglobulin that restricts the passage of antigens across mucosal surfaces

35
Q

Secretory IgA and _____ can bind to the poly-Ig receptor and be transported into the lumen of the gut or across other mucosal surfaces.

a. IgG
b. IgE
c. IgD
d. monomeric IgM
e. pentameric IgM

A

pentameric IgM

36
Q

Which of the following types of immune response are most beneficial in clearing helminth infections in the intestinal tract? (Select all that apply.)

a. production of IgG2 antibodies
b. production of IgE antibodies
c. complement fixation
d. eosinophil activation
e. antibody-dependent cell-mediated cytotoxicity
f. IFN-γ-induced production of mucus
g. TH1-derived cytokines

A

b. production of IgE antibodies
d. eosinophil activation
e. antibody-dependent cell-mediated cytotoxicity