Exam 4: Mucosal surfaces & Immun. memory/vaccination

Question 1

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

Answer 1

the integrin a4b7 on effector lymphocytes homing to mucosal tissues

Question 2

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

Answer 2

IL-5

Question 3

Secretory IgA is best described as _____.

Answer 3

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

Question 4

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

Answer 4

appendix

Question 5

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

Answer 5

TGF-b

Question 6

Laboratory animals reared in gnotobiotic conditions _____.

Answer 6

lack normal gut microbiota

Question 7

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

Answer 7

aEb7

Question 8

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

Answer 8

preferential cleavage of IgA2 over IgA1.

Question 9

“Unlike secreted mucins, membrane mucins _____.”

Answer 9

are not cross-linked by disulfide bonds

Question 10

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

Answer 10

dendritic cells

Question 11

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

Answer 11

secrete enzymes required for protein degradation

Question 12

Intracytoplasmic bacteria in enterocytes of the gastrointestinal tract are detected by

Answer 12

NOD proteins

Question 13

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

Answer 13

complement fixation

Question 14

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

Answer 14

MAdCAM-1

Question 15

_____ 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.

Answer 15

IgM.

Question 16

All of the following are examples of adjuvants, except _____.

Answer 16

RhoGAM

Question 17

Inactivated virus vaccines are made of virus particles that are not able to replicate because they have been chemically or physically treated (for example by heat) in a way that inactivates the nucleic acid. Examples are Salk polio vaccine, rabies vaccine, and influenza vaccine.

Answer 17

True

Question 18

Which of the following molecules is not elevated on the surface of memory B cells compared with naive B cells?

Answer 18

CD45RA

Question 19

Reasons complicating the development of vaccines to combat chronic diseases include all below, except_____.

Answer 19

low mutation rates in the pathogen

Question 20

RhoGAM vaccine is administered to pregnant RhD(-) women so as to _____.

Answer 20

inhibit a primary immune response to RhD antigen and prevent hemolytic anemia of the newborn

Question 21

By which process are fetal erythrocytes destroyed in hemolytic anemia of the newborn?

Answer 21

clearance of antibody-coated erythrocytes by macrophages in the fetal spleen

Question 22

Variolation and vaccination are both procedures used to confer immunological protection against the smallpox virus, variola. They both use live virus and stimulate humoral and cell-mediated immune responses against the smallpox virus. Variolation, a method used for only a short period in the 18th and 19th centuries because of the risk of developing smallpox, used dried pustules derived from humans exhibiting relatively mild symptoms of smallpox infection. Vaccination, a safer alternative causing only mild infection, used dried pustules from cows infected with cowpox

Answer 22

True

Question 23

There is no link between vaccines and autism (or Autism spectrum disorder (ASD)). Some people have had concerns that ASD might be linked to the vaccines children receive, but studies have shown that there is no link between receiving vaccines and developing ASD. In 2011, an Institute of Medicine (IOM) reportÊon eight vaccines given to children and adults found that with rare exceptions, these vaccines are very safe

Answer 23

True

Question 24

. _____ vaccines are the most effective at evoking memory responses against a virus in an immunized host.

Answer 24

Live-attenuated

Question 25

Conjugate vaccines are made by covalently coupling antigenic polysaccharide found in bacterial capsules to a carrier protein (often a toxoid). This converts the otherwise T-independent bacterial polysaccharide antigen into a T-dependent antigen. T cells respond to an epitope on the protein carrier, whereas B cells respond to epitopes on the polysaccharide portion of the conjugate. This ensures that T-cell help is provided to B cells making anti-capsule antibodies. Examples include vaccines against Neisseria meningitidis, Haemophilus influenzae and Streptococcus pneumoniae.

Answer 25

True

Question 26

The measles virus is a relatively invariant pathogen that has little, if any, antigenic change. Antibodies made by memory B cells will be just as effective in a recall response as those made in a primary challenge. In fact, antibodies made in secondary immune responses by memory B cells will be more effective because of isotype switching and somatic hypermutation. In contrast, the influenza virus is highly mutable; as a result, new strains emerge each year bearing new epitopes that have not previously stimulated a primary response. Memory response and the suppression of naive B cells restrict antibody production to only those epitopes shared by the infecting strain and the original strain. Over time, the influenza virus will express only a limited number of epitopes that are able to activate memory B cells, and the new epitopes will lack the capacity to stimulate naive B cells

Answer 26

True

Question 27

Vaccine ingredients do not cause autism [or Autism spectrum disorder (ASD)]. One vaccine ingredient that has been studied specifically isÊthimerosal, a mercury-based preservative used to prevent contamination of multidose vials of vaccines. Research shows that thimerosal does not cause ASD. In fact, a 2004 scientific reviewÊby the Institute of Medicine (IOM) concluded that ""the evidence favors rejection of a causal relationship between thimerosal-containing vaccines and autism."" Since 2003, there have beenÊnine CDC-funded or conducted studiesÊthat have found no link between thimerosal-containing vaccines and ASD, as well as no link between the measles, mumps, and rubella (MMR) vaccine and ASD in children

Answer 27

True

Question 28

_____ accounts for the production of different isoforms of the CD45 protein observed in naive, effector, and memory T cells.

Answer 28

Alternative splicing

Question 29

A 2013 CDC study added to the research showing that vaccines do not cause (or Autism spectrum disorder (ASD)). The study looked at the number of antigens (substances in vaccines that cause the body immune system to produce disease-fighting antibodies) from vaccines during the first two years of life. The results showed that the total amount of antigen from vaccines received was the same between children with ASD and those that did not have ASD.

Answer 29

True

Question 30

Tim Smith, aged 16 years, was hit by a car while riding his motorcycle. At the hospital he showed only minor abrasions and no bone fractures. He was discharged later that day. In the morning he experienced severe abdominal pain and returned to the hospital. Examination revealed tachycardia, low blood pressure, and a weak pulse. He received a blood transfusion without improvement. Laparoscopic surgery confirmed peritoneal hemorrhage due to a ruptured spleen. In addition to a splenectomy, which of the following treatments would be administered?

Answer 30

vaccination and regular boosters with capsular polysaccharides from pathogenic pneumococcal strains

Question 31

A newly identified antigen protein of Neisseria meningitidis called fHbp increases virulence by _____.

Answer 31

interfering with the alternative pathway of complement activation

Question 32

What would be the outcome if a naive B cell were to bind to pathogen coated with specific antibody made by an effector B cell in a primary immune response using FcgammaRIIB1, and simultaneously bind to the same pathogen using its B-cell receptor?

Answer 32

a negative signal leading to inhibition of the production of low-affinity IgM antibodies

Question 33

Effector memory cells enter _____, whereas central memory cells enter _____."

Answer 33

inflamed tissues; T-cell zones of secondary lymphoid tissues

Question 34

Combination vaccines consist of components that stimulate protective immunity against more than one pathogen. DTP (diphtheria, tetanus, pertussis) vaccine is an example.

Answer 34

True

Question 35

A conjugate vaccine is one that couples _____ to _____ so as to stimulate T-dependent antibody responses.

Answer 35

polysaccharide; a protein carrier

Question 36

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

Answer 36

NOD proteins

Question 37

Imagine a situation in which an individual who has a latent cytomegalovirus (CMV) infection receives a hematopoietic stem-cell transplant. Which of the following is likely to occur?

Answer 37

The transplant-derived naive T cells would be activated and give rise to memory T cells that would persist and control viral load

Question 38

Which of the following individuals would be most susceptible to fulminant meningococcal disease or septic shock when infected with Neisseria meningitidis?

Answer 38

homozygous for allotype R131 of IgG2

Question 39

The efficiency and specificity of adaptive immune defenses and immunological memory improve each time a particular pathogen is encountered because _____.

Answer 39

of affinity maturation

Question 40

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

Answer 40

FcgR

Question 41

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

Answer 41

pentameric IgM

Question 42

Which of the following statements regarding leprosy is false?

Answer 42

In lepromatous leprosy, the patient makes a TH2 response that clears the mycobacteria from the body.

Question 43

The reason that vaccines against influenza must be administered annually, unlike vaccines against measles, is _____.

Answer 43

influenza is an RNA virus with a higher mutation rate

Question 44

The measles virus is a relatively invariant pathogen that has little, if any, antigenic change. Antibodies made by memory B cells will be just as effective in a recall response as those made in a primary challenge. In fact, antibodies made in secondary immune responses by memory B cells will be more effective because of isotype switching and somatic hypermutation. In contrast, the influenza virus is highly mutable; as a result, new strains emerge each year bearing new epitopes that have not previously stimulated a primary response. Memory response and the suppression of naive B cells restrict antibody production to only those epitopes shared by the infecting strain and the original strain. Over time, the influenza virus will express only a limited number of epitopes that are able to activate memory B cells, and the new epitopes will lack the capacity to stimulate naive B cells.

Answer 44

True

Question 45

Inactivated virus vaccines are made of virus particles that are not able to replicate because they have been chemically or physically treated (for example by heat) in a way that inactivates the nucleic acid. Examples are Salk polio vaccine, rabies vaccine, and influenza vaccine.

Answer 45

True

Question 46

For IgG2 to be effective at stimulating uptake of IgG2-coated bacteria, _____.

Answer 46

an individual must express allotype H131 of FcgammaRIIA

Question 47

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

Answer 47

Commensal