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IMMUNOLOGY EXAM
Multiple Choice Questions - Choose the SINGLE BEST ANSWER
1. A large body of immunologic, epidemiologic, and genetic data indicate that tissue injury
in multiple sclerosis (MS) results from an abnormal immune response to one or more
myelin antigens. Susceptibility may be mediated by the HLA proteins related to the
known function of these molecules in the normal immune response. Regarding the
organization of HLA genes. which is TRUE:
A. The class II region consists of HLA-A, HLA-B, and HLA-C loci.
B. The class II region is subdivided into HLA-DP, HLA-DQ and HLA-DR.
C. The class III region encodes for HLA-C.
D. The class III region encodes for ß2-microglobulin.
E. All of the above are false.
2. Which of the following is likely to have undergone the greatest somatic mutation in the
variable region?
A. IgM
B. αßT cell receptor
C. γδT cell receptor
D. IgG
E. IgD
3. Tight regulation of the immune system occurs via multiple mechanisms. Which is NOT
one of these mechanisms?
A. Permanent inactivation of self-reactive cells via clonal anergy.
B. Suppression of self-reactive cells by T cells.
C Production of anti-idiotypic antibodies.
D. Release of inhibitory cytokines by macrophages.
E. Apoptosis of monocytes during their development.
4. The molecular location of the Ig and the T cell idiotope is:
A. in the hinge region.
B. in the transmembrane regions.
C. in the constant domain areas.
D. in the V region domain.
E. None of the above.
5. Regarding the structure of the MHC Class 1 molecule.
A. It contains three intracellular domains (αl, α2, α3).
B. It is 2 transmembrane polypeptides, each containing two extracellular domains
(α and ß).
C. The molecule is expressed at the cell surface in a non-covalent association with
an invariant polypeptide.
D. The complex with ß2-microglobulin appears as a five-domained molecule.
E. The peptide-binding site is shared by the two domains nearest to the cell
membrane.
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6. Which of the following properties are characteristic of antigen recognition by B cells?
A. Membrane-bound Ig binds antigen
B. Peptides. but not oligosaccharides can be bound
C. Soluble antigens are not bound
D. Internal linear peptides derived from antigen processing are required for
successful recognition.
E. All the above.
7. Atopic dermatitis (AD) is a chronic inflammatory skin disease in which T cells are
induced to secrete cytokines following the highly specific binding between the T cell
receptor (TCR) and the MHC/antigen peptide complex. Which of the following is
FALSE regarding MHC-specific T cell activation.
A. The TCR of CD4+ cells interacts with MHC Class II molecules and a peptide
antigen.
B. γδT cells require co-stimulation through binding of the CD-3 with the Fc receptor on
the antigen presenting cell.
C. Cytotoxic T lymphocytes can induce apoptosis of target cells through release of
perforins and granzymes.
D. Interaction of T helper lymphocytes with antigen presenting cells is strengthened
by adhesion molecules.
E. All of the above.
Matching: For each numbered Item (Column 1) choose the most appropriate answer (Column
2). Each answer may be used once, more than once or not at all.
8. Assay used for antigen measurement
using antibodies and an
enzyme-cojugated probe for antibody
9. Assay allowing multiple antigens to a.
be qualitatively identified all at once.
10. Assay that requires that the antigen
A be in particulate form.
A. Agglutination
B. Radioimmunoassay
C. Immunoelectrophoresis
D. Quantitative Precipitation
E. ELISA
11. A mouse was immunized wan human IgG anc a monoclonal antibody isolated
afterward was shown to react with dog IgG molecules. This is an example of:
A. van der Waal's forces
B. MHC redundancy
C. Pleomorphic variance
D. Cross reactivity
E. None of the above.
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12. Which of the following sets of compounds can be antigens?
A Proteins, Carbohydrates, Lipids, Nucleic Acids.
B. Nucleic Acids. Polysaccharides. Proteins, Lipids.
C. Nucleic Acids, Glycoproteins. Carbohydrates. Lipids.
D. Lipids, Nucleic Acids, Polysaccharides, Glycoproteins.
E. All of the above.
13. X-linked agammaglobulinaemia (XLA) is an inherited single gene disorder due to
mutations of an intracellular B cell tyrosine kinase. These patients frequently have a
deficiency in Natural Killer Cells. Regarding Natural Killer Cells, which of the following
is FALSE:
A. They have some surface markers in common with T cells.
B. They function similar to cytotoxic T lymphocytes.
C. They express CD3 and TCR.
D. They produce perforins.
E They kill via antibody-dependent cellular cytotoxic mechanisms (ADCC) via Fc
receptors.
14. In the quantitative precipitation assay:
A. Each tube contains the same amount of antibody and the antigen is varied.
B. Each tube contains the same amount of antigen and the antibody is diluted in a
serial fashion.
C. The assay is done in an agar-gel filled plate.
D. The assay is done using enzyme-substrate visualization.
E. It is specifically designed to detect different blood groups.
15. For enhancing phagocytosis, the LEAST efficient immunological component(s) bound
to the bacteria would be:
A. IgM antibody alone
B. IgM antibody + C3b
C. IgG antibody alone
D. IgG antibody + C3b
E. Mixture of IgM + IgG antibodies
16. B and T cell receptors share which of the following properties:
A. Their structure is identical.
B. The genes that encode them are the same.
C. The type of epitope to which they bind are the same.
D. They are made prior to antigen encounter.
E. All of the above.
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17. The Advisory Committee on Immunization Practices recently recommended that
college freshmen receive the polysaccharide conjugate meningococcal vaccine. Most
students have not received this previously. Which of the following is indicative of a
primary immune response?
A. Generation of Memory B cells.
B. Release of high IgE levels in serum.
C Affinity maturation of B cells for antigen.
D. Short lag times for responses.
E. All of the above.
18. In the process of antigen presentation, CD4+ T cells recognize:
A. Endogenous peptides associated with MHC class I molecules.
B. Exogenous peptides associated with MHC class I molecules.
C. Endogenous peptides associated with MHC class II molecules.
D. Exogenous peptides associated with MHC class II molecules.
E. Exogenous peptides associated with ß2-microglobulin.
19. Which property of the different classes of antibodies is most closely related to their
serum concentrations in normal patients?
A. Ability of an Ig to cross the placenta
B. Half life of the Ig class
C. Percentage of the molecular weight of each class that is polysaccharide
D. Ability of the antibody class to fix complement
E. Molecular weight of each class of Ig
20. The major properties of the acquired immune system include:
A. Specificity, memory, adaptiveness, and discrimination between self and non-self.
B. An ability produce complement components.
C. Presenting non-processed antigens to lymphocytes.
D. Secreting immunoglobulins specific for autoantigens.
E. Producing interferon-α and interferon-ß.
21. In patients with thrombotic thrombocytopenic purpura, cytotoxic antibodies mediate
hemolytic anemia. This is an example of which type of hypersensitive reaction?
A. Type I.
B. Type II.
C. Type Ill.
D. Type IV.
22. Unconjugated. free haptens:
A. are classed as immunogens.
B. are classed as antigens.
C. are classed as both immunogens and antigens.
D. are classed as neither immunogens nor antigens.
E. None of the above
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23. Complement factor H is a potent inhibitor of alternative pathway complement activation,
and its deficiency has been linked to membranoproliferative glomerulonephritis and
idiopathic (non-diarrhea-associated) hemolytic uremic syndrome. One possible
mechanism involves complement factor C5. Active fragments of C5 can lead to all the
following EXCEPT:
A. Vasodilation.
B. Contraction of smooth muscle.
C. Attachment of lymphocytes to macrophages.
D. Chemoattractant for eosinophils
E. Chemoattractant for neutrophils.
24. A lymphoma that produces terminal deoxynucleotidyl transferase (TdT) is most likely
derived from:
A. A mature B cell.
B. An immature B cell.
C. Ag IgG producing plasma cell.
D. A macrophage.
E. A mature T cell.
25. Synthesis of Class I and Class II molecules occurs in the:
A. nucleus.
B. mitochondria.
C. Golgi apparatus.
D. rough endoplasmic reticulum.
E. phagosome.
26. In the technique of nephelometry:
A. Antigen is first coated on plastic wells
B. It is a standard qualitative immune measurement technique.
C. It is done in an agar-gel filled plate
D Measures red blood cell aggregation electrophoretically
E. Finely suspended precipitates are measured by light scattering.
27. You took a sabbatical from med school and visited in Santa Catarina state, Brazil for 6
months. During your visit you contracted bancroftian filariasis (Wuchereria bancrofti),
an infection that will not resolve. The microfilariae contribute to pathology through
blockage of lymphatic vessels. The role of these lymphatic vessels involve all EXCEPT:
A. Drainage of microfilarial antigens into lymph nodes.
B. Processing of antigens for presentation to lymphocytes.
C. Delivery of mature lymphocytes to secondary lymphoid tissue.
D. Reduction in inflammatory exudate.
E. Circulation of helper and cytotoxic T lymphocytes.
28. The Class III genes of the MHC locus encode:
A. Interleukin-1ß and lymphophilin.
B. HLA-DQ.
C. ß2 microglobulin.
D. HLA-C.
E. Complement components.
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29. Myelodysplastic syndromes (MDS) are characterized by a haematopoetic insufficiency
that can lead to acute leukemia. A multistep pathogenesis caused by a clonal stem cell
defect affecting several differentiation pathways has been proposed for this disease.
Regarding stem cells all of the following cells are derived from myeloid progenitor cells
EXCEPT:
A. Eosinophils.
B. Mast cells.
C. Plasma Cells.
D. Neutrophils.
E. Dendritic Cells.
30. Which of the following properties are characteristic of antigen recognition by T cells?
A. Polysaccharide can be recognized.
B. Soluble antigens are recognized.
C. Conformational epitopes are recognized.
D. Antigen associated with an MHC molecule is recognized.
E. All the above.
31. Soluble immune complexes deposited on membranes surfaces may lead to complement
activation and inflammatory responses. Diseases such as systemic lupus erythematosus and
rheumatoid arthritis may result. This is an example of which type of hypersensitive reaction?
A. Type I.
B. Type II.
C. Type III.
D. Type IV.
32. Which component(s) of complement could be missing and still (cave the remainder of
the complement system capable of activation by the alternative pathway?
A. C1, C2. C3.
B. C1, C3, C4.
C. C2, C3, C4.
D. C1, C3, C4.
E. C1, C2, C4.
33. Which is a primary lymphoid organ?
A. Peyer's patch
A; Bone marrow
C. Lymph node
D. Red pulp of spleen
E. White pulp of spleen
34. In Wiskott-Aldrich Syndrome the deficiency in immune response is related to:
A. Lack of spleen
B. Reorganization of actin-binding cytoskeletal proteins
C. Mutation in the interleukin-2 gamma chain gene
D. Mutation in the HLA-A gene
E. Mutation in the HLA-DP gene
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35. Which of the following properties of the Fc region of human IgG can NOT be mediated
by other Ig classes?
A. Transplacental transfer
B. Complement fixation
C. Binding to mast cells
D. Secretion across epithelial layers
E. Binding J chain
36. The Reticuloendothelial System consists of all EXCEPT:
A. Kuppfer cells in the liver.
B. Dendritic cells in lymph nodes.
C. Langerhans cells in skin.
D. Glial cells in the central nervous system.
E. Aft Natural Killer cells in the lung.
37. The Ouchterlony method of immunodiffusion analysis:
A. Is very expensive to perform
B. Can directly compare the antigenic relatedness of two antigens.
C. Is a quantitative assay
D. Requires use of radioactive antibodies.
E. Measures only primary antigen; antibody interactions.
38. Which of the following functions are performed by immunoglobulin gene enhancers?
A. Stimulate immunoglobulin transcription after V gene rearrangement.
B. Stimulate immunoglobulin transcription before V gene rearrangement.
C. Enhance immunoglobulin binding to antigen.
D. Enhance somatic mutation.
E. None of the above.
39. Which is the earliest immunoglobulin protein component expressed on a B cell?
A. The IgG heavy chain
B. The 1gM heavy chain
C. The lambda light chain.
D. The kappa light chain.
E. The IgA heavy chain.
40. The American Academy of Pediatrics. Committee on Infectious Diseases, recently
issued a policy statement on the recommendations for the prevention of pneumococcal
infections. As with patients with other immune defects, patients with congenital asplenia
(defect of a missing spleen) may be given vaccines which contain all of the following
EXCEPT:
A. Pneumococcal cell wall preparations
B. Pneumococcal polysaccharide
C. Heptavalent pneumococcal polysaccharide-meningococcal outer membrane
protein complex
D. Protein conjugate-polysaccharide vaccines
E. Live. attenuated Streptococcus pneumoniae (pneumococcus).
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ANSWERS
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B
D
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D
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A
B
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B
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B
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C
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B
B
A
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B
A
B
E
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