Deck 12: Effector Responses: Cell- and Antibody-Mediated Immunity

Question 1

What is the effector molecule of humoral immunity?

A)Antibodies
B)Cytotoxic T cells
C)Dendritic cells
D)Helper T cells
E)Plasma cells

Answer 1

A

Question 2

The role of cell-mediated immunity is

A)to find cells infected with intracellular pathogens.
B)to find and eliminate cells infected with intracellular pathogens.
C)to present antigens to T_H cells.
D)to produce memory B cells.
E)to secrete antibodies.

Answer 2

B

Question 3

Cell-mediated immunity includes

A)antibodies.
B)plasma cells.
C)T_C cells.
D)both antibodies and T_C cells.
E)both plasma cells and T_C cells.

Answer 3

E

Question 4

Examples of cytotoxic effector cells include all of the following EXCEPT

A)basophils.
B)eosinophils.
C)macrophages.
D)NK cells.
E)T_C cells.

Question 5

NK T cells (NKTs) express

A)CD4.
B)CD8.
C)CD12.
D)CD33.
E)both CD4 and CD8.

Question 6

_____ describes the action of antibodies whereby antibodies bind to a pathogen and prevent the pathogen from interacting with cell receptors.

A)Antibody-dependent cell-mediated cytotoxicity
B)Antigen presentation
C)Complement fixation
D)Neutralization
E)Opsonization

Question 7

_____ describes the recruitment of phagocytic cells by the Fab portion of an antibody.

A)Antibody-dependent cell-mediated cytotoxicity
B)Antigen presentation
C)Complement fixation
D)Neutralization
E)Opsonization

Question 8

Lysis of a pathogen by MAC formation is an example of

A)antibody-dependent cell-mediated cytotoxicity.
B)antigen presentation.
C)complement fixation.
D)neutralization.
E)opsonization.

Question 9

Virally infected host cells are tagged with antigen-antibody complexes.These complexes recruit NK cells that trigger apoptosis in the infected host cell.This is an example of

A)antibody-dependent cell-mediated cytotoxicity.
B)antigen presentation.
C)complement fixation.
D)neutralization.
E)opsonization.

Question 10

Which class of antibodies is good at fixing complement?

A)IgA
B)IgD
C)IgE
D)IgG
E)IgM

Question 11

IgA is typically found as a dimer in high levels of secretions such as milk, tears, and saliva.What is the primary function of IgA in secretions?

A)To alert plasma cells of an invading pathogen
B)To neutralize toxins and pathogens
C)To secrete nonspecific enzymes such as lysozyme
D)To stimulate the growth of normal microbiota (normal flora) species
E)To trigger apoptosis in infected mucosal cells

Question 12

Monoclonal antibodies may be used to treat cancer in all of the following ways EXCEPT

A)directly binding of monoclonal antibodies may trigger apoptosis or antibody-dependent cell-mediated cytotoxicity.
B)monoclonal antibodies compete with growth factors to bind receptors on tumor cells.
C)monoclonal antibodies may prevent the formation of new blood vessels to tumors.
D)monoclonal antibodies may recruit T_H cells to a developing tumor.
E)monoclonal antibodies may serve as a vector to target tumor cells for toxin mediated therapy.

Question 13

Fc-receptor molecules tend to have short cytoplasmic tails.How does this influence signaling events within the Fc-receptor cell?

A)The Fc-receptor is adjacent to secondary messengers (e.g., MAP kinase) that translocate into the nucleus to affect transcription.
B)The Fc-receptor is dependent upon a coreceptor (e.g., ITAM or ITIM) that will trigger signaling events within the cell.
C)The Fc-receptor is not directly involved in a signaling event.
D)The Fc-receptor serves only to enhance or dampen a signaling event.
E)The Fc-receptor translocates into the cytoplasm where it will bind to secondary messengers.

Question 14

Which Fc-receptor is responsible for triggering the release of histamine, proteases, and other inflammatory signals from IgE?

A)Fc ? receptor
B)Fc ? receptor
C)Fc ? receptor
D)Neonatal Fc-receptor
E)Polymeric immunoglobulin receptor (pIgR)

Question 15

Why is IgM the class of antibody able to form large polymers?

A)IgM is the strongest binding antibody class.
B)IgM is considered the most important type of antibody.
C)IgM has low affinity and benefits from having a large number of binding sites.
D)IgM is used exclusively against parasites.
E)IgM requires form polymers traveling through the body.

Question 16

Which type of antibody is MOST effective against the largest variety of pathogens?

A)IgM
B)IgG
C)IgA
D)IgE
E)IgD

Question 17

Cell-mediated effector cells include

A)CTLs and NKT cells.
B)Plasma cells and dendritic cells.
C)T_C cells and NK cells.
D)T_C cells, NKT cells, and NK cells.
E)T_C cells and memory T_H cells.

Question 18

The Fas ligand (FasL) represents a key signaling pathway among cell-mediated effector cells.What is the function of the Fas-FasL signaling pathway?

A)Activation of the Fas-FasL signaling pathway triggers apoptosis.
B)Binding of Fas to FasL induces phagocytosis by dendritic cells.
C)Expression of Fas occurs only on naïve B cells.
D)FAS-FASL binding recruits T_H cells.
E)TNF- ? is released by NKT cells triggering histamine release in infected target cells.

Question 19

At what location are naïve T_C cells activated to become CTLs?

A)Blood stream
B)Bone marrow
C)Lymph node
D)Site of infection
E)Thymus

Question 20

CTLs mediate a powerful and lethal immune response to infected host cells.Which of the following steps is NOT involved with CTL activation and function?

A)Antigen presented with MHC class I is recognized by CTLs.
B)APC presentation occurs to both T_C and T_H cells.
C)Fas-FasL signaling pathway is activated, triggering apoptosis.
D)Histamine is released from cytoplasmic granules, recruiting macrophages to the site of infection.
E)Perforin and granzymes are released, triggering apoptosis of infected cell.

Question 21

Precursor CTLs are characterized by each of the following EXCEPT

A)they do not divide.
B)they do not express high affinity for CD25.
C)they express CD4.
D)they lack cytotoxic activity.
E)they produce low amounts of IL-2.

Question 22

Which of the following statements about NK T cells is TRUE?

A)Activated NKT cells can act as both a T_H and a T_C cell.
B)CD4 is expressed by all NKT cells.
C)NKT cells rely on p53 expression to cause apoptosis in an infected host cell.
D)NKT cells express most of the T cell lineage characteristics.
E)The TCR on NKT cells recognizes antigens presented with MHC class I and class II molecules.

Question 23

Licensing on an NK cells refers to

A)activation of an NK cell by MHC class II displayed peptide antigen.
B)expression of IFN- ? and TNF- ? by NK cells
C)production of memory cells.
D)suppressing the activity of a self-recognizing NK cell.
E)testing an NK cell to ensure that it will not target healthy host cells.

Question 24

In a recent experiment, NK cells were collect from an MCMV infected mouse and placed into a healthy mouse.Upon exposure to the MCMV virus, the healthy mouse quickly mounted an immune response.How could these results BEST be interpreted?

A)MCMV virus failed to infect the healthy mouse.
B)NK cells show memory and are quickly able to recognize MCMV infected cells in the healthy mouse.
C)Plasma cells were transferred along with NK cells and produced antibodies that target MCMV virus particles.
D)T_C cells were transferred along with the NK cells and have been targeting MCMV virus particles.
E)T_H cells were transferred to the healthy mouse instead of NK cells and have stimulated B cells to activate.

Question 25

How many subpopulations of T_C cells are there?

A)One: T_C
B)Two: T_C1 and T_C2
C)Three: T_C1, T_C2, and T_C3
D)Five: T_CA, T_CD, T_CE, T_CG, and T_CM
E)It varies depending on the type of infection that is found.

Question 26

MHC tetramers

A)are a novel way to detect and follow specific T-cell populations within an organism.
B)are found only in mice though a parallel system in humans is under current investigation.
C)describe high-functioning T_C cells found in autoimmune response.
D)represent novel immunotherapy for patients with Crohn's disease.
E)use fluorescent staining to bind to MHC class I molecules on dendritic cells.

Question 27

A new pathogenic bacterium has been discovered - it is an intracellular parasite and can prevent MHC molecules from being properly made in infected cells.Which of the following cell types would be MOST effective at fighting this pathogen?

A)CTL
B)NK cell
C)B cell
D)Dendritic cell
E)Basophil

Question 28

Which of the following effector function components would have the GREATEST impact on a patient's cells if the cells were not functioning properly during a viral infection?

A)Perforin
B)Granzyme B
C)Fas
D)MHC I
E)FcR

Question 29

Which molecule can induce the GREATEST variety of effector functions?

A)MHC I
B)MHC II
C)TCR
D)Bound antibody
E)NCRs

Question 30

Which two classes of antibodies are BEST at agglutinating pathogens? Explain.

Question 31

Compared to other effector functions, why is there such diversity in antibody FcR interactions?

Question 32

Why were early monoclonal antibodies poor therapeutics? Support your answer by providing two ways that these antibodies were modified to make them more suitable for human use.

Question 33

What three steps must occur before a CTL is ready to kill target cells? Explain why these steps must occur.

Question 34

What are the two means by which activated CTLs kill target cells? Explain the significance of both events.

Question 35

What two properties of NK cells make them innate-like in their function? What two properties are more closely aligned with the adaptive immune system? Explain.

Question 36

Why are NK cells such an important component of the immune system?

Question 37

Identify the components of an NKT cell that are NK-like and those that are T-cell-like.Which components are like neither? Explain.

Question 38

Compare and contrast the ways in which antibodies and T cells interact with their cognate antigen.Explain how this benefits the host.

Question 39

The use of CAR therapy has been a major breakthrough in cancer treatment.CAR stands for "Chimeric Antigen Receptor," and it is a combination of the antigen-binding domain of an antibody and the intracellular domain of the TCR.What advantage might this construct have over endogenous cellular machinery?