Question 1 (1 point)
Choose the idem least likely to contribute to immunoglobulin diversity
a. Random combinations of V,D,J gene segments
b. Removal or addition of nucleotides at V-Jor V-D-J junctions
c. Two different light chains
d. recombinations betweem light and heavy chain gene segments
e. Antibody reactive site made up of two different chains
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Question 2 (1 point)
CD 40 Ligand is expressed by which of the following?
a. B cells
b. dendritic cells
c. resting T cells
d. Activated T cells
e. all leucocytes
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Question 3 (1 point)
Choose the one which DOES NOT BELONG: Class I MHC antigens have the following
properties:
a. they are presenting antigens to cytotoxic T cells
b. they are products of the major histocompatibility complex
c. they are found on all nucleated cells
d. they are found only on B cells, macrophages and activated T-cells
e. they are codominantly expressed
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Question 4 (1 point)
Cytokines always act:
a. by binding to specific receptors
b. in an autocrine fashion
c. at long range
d. antagonistically with other cytokines
e. synergistically with other cytokines
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Question 5 (1 point)
Cytotoxic T cells are effector cells of cell mediated immunity. They recognize antigens of
a pathogen, expressed on the surface of the host cells, in association with class I MHC
antigens. They are important in combating which of the following agents?
a. bacteria
b. viruses
c. allergens
d. toxins
e. lymphokines
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Question 6 (1 point)
Choose the incorrect statement regarding either B or T cell recognition of Antigen
a. Both B and T cells use membrane bound receptors to bind antigen
b. Both B cells and T cells see antigen in context of MHC molecules
c. T cells recognize peptide fragments
d. B cells can recognize a wide variety of antigens
e. B cell antigen recognition is much less regulated than T cells
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Question 7 (1 point)
Maturing dendritic cells that migrate to a lymph node from peripheral tissues end
up mainly in:
a. Follicles
b. High endothelial venules
c. The medullary sinus
d. T cell zones
e. Efferent arterioles
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Question 8 (1 point)
MHC Polymorphorism:
a. restricts binding of CD4 but not CD8 cells
b. is present primarily in the peptide-binding regions of MHC proteins
c. is the result of random association of many alpha and beta genes
d. restricts the ability of B cells to bind antigens
e. results in expression of dozens of MHC alleles on each antigen presenting cells
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Question 9 (1 point)
A child who suffers from a persistent viral infection is found to have a deficiency in
lymphocyte production and very few T and B cells. Other bone marrow-derived
cells are produced in normal numbers, and MHC molecule expression on cells
appears normal. Transfusion of mature T cells from an unrelated donor who had
recovered from a previous infection by the same virus would not be expected to help
the child clear his infection. Which one of the following is a reasonable explanation
for why this therapeutic approach would fail?
a. Viral infections are cleared by antibodies, not T cells.
b. The patient's own immune system would destroy the transfused T cells before
they could respond to the viral infection.
c. T cells recognize peptides, not viral particles.
d. Donor T cell viral antigen recognition is restricted by MHC molecules not
expressed in the patient.
e. In responding to the previous infection, the donor would have used up all his T
cells specific for that virus.
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Question 10 (1 point)
The role of macrophages during an antibody response is to:
a. make antibody
b. lyse virally infested target cells
c. process antigen and "present" it
d. activate the complement cascade
e. help the generation of natural killer cells
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Question 11 (1 point)
Which one of the following statements about T cell tolerance to self proteins is
accurate?
a. Self proteins are not presented by the class I pathway because only microbial
proteins, and not self proteins, are ubiquinated in the cytosol.
b. Peptides derived from self proteins are not presented by the class I or class II
pathways because MHC molecules are expressed only in response to infections.
c. Self proteins are not presented by the class II pathway because endosomal acidic
proteases digest microbial proteins but not eukaryotic proteins.
d. Self peptide/self MHC complexes are formed and displayed by antigen-presenting
cells in both class I and class II MHC pathways, but T cells that recognize these
complexes usually are not present or are functionally inactive.
e. Peptides derived from self proteins are not displayed by MHC molecules because
they usually are displaced by the more abundant microbial peptides.
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Question 12 (1 point)
The three major families of antigen-binding molecules in the adaptive immune
system are:
a. Toll-like receptors, MHC molecules, and antibodies
b. MHC molecules, integrins, and antibodies
c. Antibodies, T cell receptors, and selectins
d. Antibodies, T cell receptors, and MHC molecules
e. MHC molecules, antibodies, and Fc receptors
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Question 13 (1 point)
Which one of the following statements about peptide binding to MHC molecules is
true?
a. MHC molecules preferentially bind peptides derived from foreign (e.g.,
microbial) proteins and not peptides derived from self proteins.
b. Each type of MHC molecule and each allelic variant of each type have a narrow
specificity for a single peptide with a particular amino acid sequence.
c. The affinity of peptide binding to MHC molecules is higher, on average, after
chemokine stimulation of a cell.
d. An MHC molecule has only one peptide-binding site, which accommodates only
a single peptide at a time.
e. Peptide binding to class I MHC molecules involves noncovalent interactions,
whereas peptide binding to class II MHC molecules is covalent.
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Question 14 (1 point)
Failure of self-tolerance is the cause of which one of the following types of diseases?
a. Allograft rejection
b. Autoimmunity
c. Atopy
d. Anergy
e. Acne
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Question 15 (1 point)
A 29-year-old woman gives birth to an infant who is lethargic, jaundiced, and severely
anemic and has an enlarged liver and spleen. The mother is RhD negative and the father
is homozygous RhD positive. This is their second child.
a. Type I hypersensitivity
b. Type II hypersensitivity
c. Type III hypersensitivity
d. Type IV hypersensitivity
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Question 16 (1 point)
Which one of the following statements concerning autoimmune disease is true?
a. Autoimmunity manifests as organ-specific, not systemic, disease.
b. Infectious microorganisms are frequently present in autoimmune lesions.
c. Effector mechanisms in autoimmunity include circulating autoantibodies, immune
complexes, and autoreactive T lymphocytes.
d. Among the genes associated with autoimmunity, associations are particularly
prevalent with class I MHC genes.
e. Many autoimmune diseases show higher incidence in males than in females.
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Question 17 (1 point)
A 15-year-old girl experiences flushing pruritus, and urticaria, which began during
a class field trip to the local botanical gardens. She is restless and uncomfortable
and describes a sensation of "burning" and "pulling" in her skin. Which of the
following best characterizes her condition?
a. Macrophage activation of CD4+ T cells
b. CD8+ T cell-mediated cytolysis of keratinocytes in the skin
c. CD4+T cell-mediated delayed-type hypersensitivity to poison ivy
d. Complement activation by antibody-antigen immune complexes in the skin
e. Activation of IgE-coated mast cells leading to histamine release
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Question 18 (1 point)
Immediate hypersensitivity differs from delayed-type hypersensitivity in which one
of the following ways?
a. Immediate hypersensitivity is a CD4+ T cell-mediated disease.
b. Immediate hypersensitivity does not require previous exposure to an antigen.
c. Immediate hypersensitivity does not involve inflammation.
d. Immediate hypersensitivity is driven by cytokines such as interleukin (IL)-4, IL-5,
and IL-13.
e. Immediate hypersensitivity typically leads to granuloma formation.
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Question 19 (1 point)
Mast cell degradulation and Eosinophil activation are associated with
a. Th1 cells
b. Th2 cells
c. IgG
d. INF-gamma
e. macrophage activation
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Question 20 (1 point)
A 22-year-old man who recently emigrated from South Africa received a PPD skin
test for tuberculosis as part of the health screening requirements for a new job in a
hospital. Within 48 hours there was an erythematous, indurated lesion 15 mm in
diameter at the site on the forearm where the PPD was administered. A histologic
section of this type of reaction is shown in the figure above. Which type of
immunologic reaction has occurred at this site?
a. Immediate hypersensitivity
b. Anaphylaxis
c. Antibody-dependent cellular cytotoxicity (ADCC)
d. Autoimmune
e. Delayed-type hypersensitivity (DTH)
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