Download 1999 examination

Microbiology 532
Immunology Examination
October 14, 1999
All questions have equal point value.
Multiple Choice (choose the best answer)
1.
When one is describing “passive” immunity, one is referring to:
a.
b.
c.
d.
e.
2.
In order for a cell to communicate with another cell using a soluble “factor” as the “message,” the
second cell must possess:
a.
b.
c.
d.
e.
3.
the epitope specificity of the antibody.
Fc binding
complement receptors
cytokines
none of the above.
Martian immunoglobulin molecules follow the same rules of proportions that are found in human
immunoglobulins. If you were told that Martian light chains had a molecular weight of 50,000
kDa, what would you expect the molecular weight of a single heavy chain to be?
a.
b.
c.
d.
e.
6.
two heavy chains and four light chains
ten heavy chains and ten light chains
two light chains and two heavy chains.
two kappa chains and two lambda chains
none of the above.
The variable regions of the light and heavy chains of the immunoglobulin molecule define:
a.
b.
c.
d.
e.
5.
a receptor for the message.
a Walkman radio
an Fc receptor
a complement receptor
none of the above.
The prototype structure of the immunoglobulin molecule is composed of:
a.
b.
c.
d.
e.
4.
transfer of immune cells from one individual to another.
immunization with a vaccine.
a bone marrow transplant.
transfer of preformed soluble immune components (immunoglobulins).
none of the above.
100,000 kDa
50,000 kDa
25,000 kDa
200,000 kDa
none of the above.
The J-chain is an important polypeptide found in:
a.
b.
c.
IgG
IgD
IgE
Microbiology 532
d.
e.
Immunology Examination
polymeric immunoglobulins
none of the above.
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Microbiology 532
7.
Fc-binding of the IgE immunoglobulin is associated with the:
a.
b.
c.
d.
e.
8.
to function as an antigen receptor on B-lymphocytes.
to mediate ADCC.
to mediate NK activity.
to activate the complement cascade.
none of the above.
Affinity is primarily a function of:
a.
b.
c.
d.
e.
10.
Fab fragment
extra constant region of the -chain.
Fd
ICAM
none of the above.
The primary role of IgD antibody is:
a.
b.
c.
d.
e.
9.
Immunology Examination
how much you like someone.
multiple antigen binding sites.
Fc receptors on Mast cells.
the quality of the epitope fit in the antigen binding site.
none of the above.
Avidity is primarily a function of:
a.
b.
c.
d.
e.
the interaction between a single epitope and a single Fab fragment.
the strength of binding to Fc receptors.
the interactions between the cell adherence molecules and neutrophils.
multiple simultaneous interactions between antibodies and epitopes.
none of the above.
True/False (Please use “a” for true and “b” for false on your answer sheet)
11.
High avidity antibody is less effective at neutralizing toxins.
12.
Cross-reaction is the result of antigen binding sites aging and losing their epitope specificity.
13.
An ELISA assay is very sensitive due to its ability to detect complement activation following
antibody-antigen interactions.
14.
Rings form in the radial immunodiffusion assay because antigen-antibody complexes precipitate at
the leading edge of the diffusing antigen, where the antigen concentration is maximum.
15.
Latex bead agglutination may occur with IgM antibodies and soluble antigens if the antigens are
first attached to latex beads.
16.
The complement system is considered to be an amplification system because a single antigenantibody reaction may result in the generation of considerable complement activity,
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Microbiology 532
Immunology Examination
17.
Complement may only be activated when a specific antigen-antibody reaction occurs.
19.
The clonal selection theory proposed that, prior to encounter with antigen, there exists a large
number of B cells pre-committed to specific epitopes.
20.
CD antigens are antigens on the surface of cells that represent, the type of cell, stage of differentiation or its function.
Multiple Choice (choose the best answer)
21.
The MHC-encoded Class 1 and Class 2 antigen receptors are located on:
a.
b.
c.
d.
e.
22.
T cells are not usually stimulated by antigen in the absence of the antigen presenting cell because:
a.
b.
c.
d.
e.
23.
antigen receptors comprised of IgM or IgD antibodies.
remote sensing.
complement receptors.
a homing mechanism.
none of the above.
Plasma cells are:
a.
b.
c.
d.
e.
26.
is usually not a macrophage or monocyte.
is usually a T cell.
produces cytokines which influence the T cell while it is presented antigen.
produces ICAMs which are critical for diapedesis.
none of the above.
B cells recognize antigen using:
a.
b.
c.
d.
e.
25.
antigen peptides must be presented to the T cell while bound to the MHC encoded receptor
on the antigen presenting cell.
most T cells in the circulation need thymic hormones secreted by the antigen presenting cell
to mature to a plasma cell.
Phagocytosis by T cells must be stimulated by antigen presenting cells.
all of the above.
none of the above.
The antigen presenting cell
a.
b.
c.
d.
e.
24.
T cells
B cells
megakaryocytes
antigen presenting cells.
none of the above.
B cells that have been triggered by antigen to mature to antibody-producing cells.
T cells that have migrated to germinal centers of the body.
Cells that make plasma.
circulating B cells.
none of the above.
Cytokines are:
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Microbiology 532
a.
b.
c.
d.
e.
Immunology Examination
vascular addressins.
a form of ICAM.
a type of FACS analysis.
soluble “messages” having no antigen specificity produced by cells to communicate with
other cells.
none of the above.
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27.
Adjuvants are often required during immunization to:
a.
b.
c.
d.
e.
28.
mediate death in target cells.
buy a round of beer at the bowling alley.
stimulate immune responses of antigens in privileged sites.
recognize antigen peptides presented by MHC encoded receptors.
none of the above.
The lag phase of the primary response is:
a.
b.
c.
d.
e.
30.
to deaden the pain of the injection.
to enhance the immunogenicity of weak antigens.
suppress excess macrophage activity.
suppress excess T cell responsiveness.
none of the above.
Induction of apoptosis is a method by which cytotoxic T cells
a.
b.
c.
d.
e.
29.
Immunology Examination
short due to the presence of T cell effector cells.
short due to the earlier anamnestic response.
of the same duration as the booster response lag phase.
long, due to the time it takes to select and expand cell populations that recognize a specific
antigen.
none of the above.
The lag phase of the anamnestic response is:
a.
b.
c.
d.
e.
very long, due to the large number of memory cells in the circulation.
very short due to the lack of antigen presenting cells.
very short when dendritic cells are absent.
very short, due to the presence of memory cells.
none of the above.
True/False (Please use “a” for true and “b” for false on your answer sheet)
31.
Affinity maturation is the result of antibodies adapting to a specific epitope once they are
synthesized.
32.
The innate mechanisms of host immunity do not play a role in the defense of the body unless the
specific immune response fails.
33.
The ability of a microorganism to establish an infection is generally a function of its possession of
a receptor for a specific substance on a host cell.
34.
Opsonization enhances the ability of phagocytic cells to engulf bacteria because it stimulates
chemotaxis.
35.
Fc and complement receptors on phagocytic cells bind opsonized bacteria and pull them into
phagocytic vacuoles.
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Immunology Examination
36.
Atopic individuals are people who tend to make excessive amounts of IgA antibodies.
37.
Mast cell degranulation occurs as a result of cross-linkage to IgE Fc receptors on Mast cells.
39.
The genetic factors associated with atopy insure that you will develop the same allergies as your
parents.
40.
Desensitization injections are thought to stimulate suppressor cell activity and reduce IgE synthesis
in atopic patients.
Multiple Choice (choose the best answer)
41.
The target of the complement activity is determined by:
a.
b.
c.
d.
e.
42.
Complement damage is generally highly localized due to:
a.
b.
c.
d.
e.
43.
they present antigen to plasma cells.
they are capable of mediating ADCC.
neutrophil chemotactic activity is generated upon complement activation.
neutrophil diapedesis is difficult in the presence of chemotactic factors.
none of the above
Serum from an Rh positive patient agglutinates red blood cells from a patient who is AB and Rh
positive. What blood type is the first patient?
a.
b.
c.
d.
e.
45.
very short half-lives of the activated complement components.
very low concentrations of the unactivated complement components in serum.
the inability to activate the system in the presence of IgG antibodies.
the natural affinity of complement for antigen presenting cells.
none of the above
Neutrophils are the primary cellular infiltrate in an antibody-mediated hypersensitivity because:
a.
b.
c.
d.
e.
44.
Fc receptors.
vascular addressins.
the cytokine concentrations in the vicinity of the primary lymphoid organs.
the specific antibody-antigen reaction and the location of immune complex formation.
none of the above.
It can’t be determined from the information provided.
Type A
Type B
Type O
Type AB
Hemolytic disease of the newborn (Rh incompatibility) is the result of:
a.
b.
c.
d.
an Rh negative mother conceiving an Rh positive child.
ABO incompatibility.
an Rh positive mother conceiving an Rh negative child.
an Rh negative mother conceiving an Rh negative child.
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e.
46.
d.
e.
c.
d.
e.
the microorganism shares antigens with the host.
the microorganism encounters the innate host defense mechanisms.
the microorganism invades a primary lymphoid organ.
the microorganisms activates the alternate complement pathway.
none of the above
Antigens in immunologically privileged sites:
a.
b.
c.
d.
e.
50.
These substances bind to MHC-encoded receptors and trigger cytokine production.
The low molecular weight substances react with tissues, forming a hapten-carrier complex,
and take advantage of the higher molecular weight of the tissue and serum proteins to become immunogenic.
These substances coalesce into large complexes and directly trigger plasma cells.
The substances trigger the complement cascade and cause neutrophils to accumulate and to
serve as antigen presenting cells.
none of the above.
Autoimmunity may occur following an infection when:
a.
b.
c.
d.
e.
49.
Free antigen is rapidly filtered out of the body by the kidneys.
Antigen presenting cells rapidly bind all of the antigen in their MHC-encoded receptors
Free antigen causes the activation of the complement system and the protease activity of one
of the complement components degrades free antigen.
The free antigen is being bound in immune complexes.
none of the above
Contact dermatitis generally occurs against substances that are considered to have a molecular
weight too small to induce an immune response. How do these substance induce an immune response?
a.
b.
48.
none of the above
During serum sickness, the concentration of free antigen in the serum drops rapidly at the onset of
serum sickness symptoms. Why?
a.
b.
c.
47.
Immunology Examination
are given special honors due to their outstanding achievements.
are highly immunogenic.
tend to be processed more efficiently by NK cells.
do not generally trigger immune responses.
none of the above
Innate host defense mechanisms are critical to the protection of the body because:
a.
b.
c.
d.
e.
they utilize pre-committed T cells that have already been induced by other immune responses.
they are the last line of defense of the body after the immune system fails.
they are highly specific for the invading pathogens.
they provide immediate, continuous protection without the need for a specific immune response.
none of the above
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