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Biol. 456/556, Immunology
Thursday, February 8, 2018
EXAM A
First Exam, Spring Semester 2018
Please pick the BEST answer from the list of potential answers and use the scantron to record your choice.
MAKE SURE YOU HAVE FILLED IN YOUR NetID AND BANNER ID NUMBER ON THE SCANTRON
1. When Mosier demonstrated that plastic adherent cells were needed to generate an immune response in vitro
he was discovering what?
A. Macrophages can phagocytose antigens.
B. Both B cells and T cells are needed to generate an immune response in vitro.
C. Macrophages also produce antibodies.
D. Macrophages are needed to present antigens to lymphocytes.
2. Henry Claman exposed mice to ionizing radiation (X-rays) so that they could no longer make their own
antibody response. However, transferring spleen cells alone reconstituted the ability to make an antibody
response against specific antigen. What conclusions were drawn from this result?
A. The spleen is the mouse equivalent of the avian Bursa of Fabricius.
B. The spleen functions like second thymus in mice.
C. The spleen contains all the cell types necessary for an antibody response.
D. The spleen is resistant to radiation.
3. Which of the following mechanisms does a B cell use to convert from synthesizing cell surface associated
antibody and producing the secreted form?
A. Mutations added by terminal deoxynucleotidyl transferase.
B. Alternative mRNA splicing.
C. Changing which light chain is used by switching from kappa to lambda.
D. Cleaving the protein from the surface using a protease.
4. Which of the following support that antibody producing cells are a type of lymphocyte?
A. Normal healthy people have antibodies that bind red blood cells from some other people.
B. Antibody activity is associated with the gamma-globulin fraction of serum proteins.
C. Bence-Jones proteins are found in the serum of patients with thymomas.
D. None of the above.
5. Edward Jenner experimented with deliberately giving people cowpox and then testing them to see if they
were immune to smallpox. He was successful in showing that cowpox would induce immunity to smallpox.
Which of the following best explains his success?
A. The pathogen that causes cowpox must be similar enough to the one that causes smallpox that
immunity to one induces immunity to the other.
B. Cowpox and smallpox are the exact same disease.
C. Being infected with cowpox prevents exposure to smallpox.
D. Dairy farmers are a dime-a-dozen, so who cares if you lose a few to smallpox.
6. The recombination activating gene (RAG) enzymes are responsible for which of the following properties of
V(D)J recombination?
A. Recognizing the recombination signal sequenes.
B. Enforcing the 12/23 rule.
C. Forming hairpins at the end of the coding DNA breaks.
D. All of the above.
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Biol. 456/556, Immunology
Tuesday February 8, 2018
EXAM A
First Exam, Spring Semester 2018
7. By demonstrating that immunity could be transferred from an immune animal to a non-immune animal
using serum, von Behring and Kitasato were demonstrating which of the following?
A. Immunity can only be transferred with cells.
B. Immunity can be transferred with non-cellular, soluble factors.
C. Converting blood to serum makes it immune.
D. Serum contains antigens to immunize animals with.
8. Which of the following causes a B cell to be aware that it has encountered the antigen it is specific for?
A. Macrophages presenting the antigen to the B cell.
B. VpreB signals the presence of successfully produced heavy chains on the cell surface.
C. The antigen binds more than one cell surface antibody and cross-links them.
D. All of the above.
9. Which best describes the contribution of the enzyme Terminal deoxynucleotidyl transferase (Tdt) to
antibody diversity?
A. Tdt introduces mutations into the CDR1 and CDR2 regions of heavy and light chain variable
regions.
B. Tdt randomly adds nucleotides the DNA ends that form the junctions encoding CDR3.
C. Tdt cuts the DNA at the recombination signal sequences.
D. Tdt kills off the cells that are by chance anti-self by enzymatically destroying the cells’
chromosomes.
10. How does Burnet’s clonal selection theory differ from Paul Ehrlich’s first attempt to explain the nature of
antibody production with his side chain theory? Which of the following is different between the two
theories?
A. Each antibody-producing cell has only a single antigen specificity.
B. Antigens select which antibody will be made.
C. Antibodies are displayed on the surface of the antibody-producing cell.
D. Each antibody molecule has its own antigen specificity.
11. When immunizing an animal with a hapten such as dinitrophenol (DNP) it is typically attached to a carrier
molecule such as bovine serum albumin (BSA). Based on what you now know about B cell biology, what
purpose is the carrier serving?
A. The carrier is oposonizing the hapten.
B. The carrier provides the epitopes that cross-react with DNP.
C. The carrier acts as a platform for multiple haptens to cross-link the surface antibody on B cells.
D. The hapten is too small of an epitope for antibodies to bind without the carrier.
12. Combinatorial diversity in antibodies refers to which of the following?
A. The possible combinations of V, D, and J segments in the heavy chain.
B. The use of both maternal and paternal alleles when synthesizing antibody.
C. The possible combinations of different heavy and light chains.
D. The variation in the junctions between V(D)J segments.
13. Which of the following contributes to the clonal nature of B cells?
A. Unique combinations of V, D and J segments during B cell development.
B. Unique nucleotide combinations in the V, D, J junctions.
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Biol. 456/556, Immunology
Tuesday February 8, 2018
EXAM A
First Exam, Spring Semester 2018
C. Allelic exclusion of the antibody genes.
D. All of the above.
14. In the junctions between the recombined V and J segments encoding a light chain variable domain, there are
nucleotides that are formed when DNA hairpins structures are opened or resolved. These nucleotides are
referred to as which of the following type?
A. H nucleotides.
B. N nucleotides.
C. P nucleotides.
D. T nucleotides.
15. If you set up a Mishell-Dutton style culture with bone marrow cells alone and exposed them to antigen,
would you expect to be able to detect antibody production in these cultures?
A. Yes.
B. No.
16. What does the Jerne plaque assay quantify?
A. Quantity of antibody in serum.
B. Ratio of 19S to 7S antibody.
C. Number of antibody secreting cells.
D. Binding affinity of antibody.
17. Which of the following statements is FALSE?
A. B cells determine their antigen specificity prior to encountering the antigen.
B. B cells determine their antigen specificity after encountering the antigen.
18. True or False? Consistent with Burnet’s clonal selection theory, a single B cells should be able to only use
both maternal and paternal heavy chain genes simultaneously.
A. True.
B. False.
19. If the antibody heavy chain locus contained 100 different germ-line V segments, 5 different germ-line D
segments, and 2 different germ-line J segments, how many different antibody specificities could be
produced by combinatorial diversity?
A. 100.
B. 107.
C. 1000.
D. Not enough information.
20. By demonstrating that a population of immature B cells, or pro-B cells, contains more anti-self reactive B
cells than do mature B cells, Michel Nussenzweig was proving which aspect of Burnet's clonal selection
theory?
A. B cells start out being specific for more than one antigen.
B. Each B cell randomly generates it's own unique specificity.
C. Anti-self B cells are being eliminated early in their development.
D. Newborn animals have autoimmune diseases.
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Biol. 456/556, Immunology
Tuesday February 8, 2018
EXAM A
First Exam, Spring Semester 2018
21. Which of the following statements is NOT a part of Burnet’s clonal selection theory?
A. A single antibody-producing cell is capable of making antibodies of only a single antigen specificity.
B. Antibody producing cells use their antibody as a cell surface receptor to detect antigen.
C. Antibody producing cells that are specific for self-antigens never exist at any time during
development.
D. Antibody producing cells proliferate.
22. If an F(ab) fragment derived from a 7S antibody were further reduced to break disulfide bonds, what
polypeptides fragments would be generated?
A. Intact Fc chains alone.
B. Intact light chains and partial heavy chains.
C. Partial heavy chains alone.
D. Partial light chains alone.
23. Which of the following is NOT part of Paul Erhlich’s side chain theory of antibody production?
A. A single cell can only make antibodies of a single specificity throughout its life.
B. The antibodies are displayed on the surface of antibody producing cells.
C. Antibodies with different specificities are present on the surface of a single antibody producing cell.
D. Interaction of antigen determines which antibody a cell will secrete as a soluble molecule.
24. Which of the following is the best definition of a hapten?
A. Haptens are any epitope on an antigen.
B. Hapten is another name for the complementarity determining region.
C. Haptens are large molecules that contain multiple epitopes.
D. Haptens are molecules that cannot stimulate an antibody response alone but can be a binding site for
antibodies.
25. Framework region 2 of the variable domain of an immunoglobulin heavy chain protein is encoded by what
part of the light chain gene?
A. The junction of the V and J segments.
B. The D segments.
C. The J segment.
D. The V segment.
26. Which of the following best defines the difference between a precipitation reaction and an agglutination
reaction using serum from an immune mouse?
A. Agglutination reactions are the cross-linking of haptens, whereas precipitation reactions cross-link
cellular antigens.
B. Agglutination reactions are the cross-linking of cellular or non-soluble antigens, whereas
precipitation reactions cross-link soluble antigens.
C. Agglutination reactions are with antibodies, precipitation reactions occur in non-immune serum.
D. None of the above.
27. Which of the following is the best definition of allelic exclusion of the immunoglobulin genes?
A. Using both immunoglobulin heavy and light chain genes.
B. Using only the maternal or the paternal immunoglobulin heavy and light chain loci in one B cell.
C. Using both the maternal and the paternal immunoglobulin heavy and light chain loci in one B cell.
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Biol. 456/556, Immunology
Tuesday February 8, 2018
EXAM A
First Exam, Spring Semester 2018
D. B cells are haploid not diploid like germ cells.
28. Almroth Wright found that serum from an immune animal enhanced the rate of macrophage phagocytosis of
bacteria relative to serum from a non-immune animal. What can you conclude from his observations?
A. Factors in the serum of immune animals facilitate phagocytosis by macrophages.
B. Phagocytosis cannot take place in the absence of immune serum.
C. Allowing blood to clot and convert to serum alters its composition and allows phagocytosis to occur.
D. Macrophages are not influenced by the immune status of the host animal.
29. Two serum samples are tested in an agglutination reaction to determine their equivalence point. Both
samples agglutinate the antigen however sample #1 requires less antigen to reach its equivalence point than
does sample #2. How would you interpret this observation?
A. Sample #1 contains antibodies of lower binding affinity than sample #2.
B. Sample #2 contains a higher concentration of antibodies than sample #1.
C. Sample #1 is from a patient who is non-immune to the antigen.
D. Sample #1 contains a higher concentration of antibodies than sample #2.
30. Hematopoietic stem cells have which of the following properties?
A. They are self-renewing.
B. They may differentiate into myeloid cells.
C. They may differentiate into lymphoid cells.
D. All of the above.
31. Which of the following support the idea that self-tolerance in the immune system is learned and not
genetically pre-determined?
A. Exposing fetal animals to a foreign antigen induces tolerance to that antigen.
B. Removal of the thymus early in development impairs the ability to reject skin grafts later.
C. Juvenile animals respond to all antigens at birth, but lose this ability when mature.
D. Children with thymomas develop autoimmune disease.
32. Antibody activity can be found in which fraction of serum proteins?
A. The 19S fraction.
B. The α globulin fraction.
C. The heavy chain fraction.
D. All of the above.
33. During development, if a B cell fails to rearrange either of its two Ig heavy chain loci correctly and produce
a functional antibody heavy chain protein, which of the following will never be present on the surface of the
B cell?
A. Antibody heavy chains.
B. VpreB.
C. Antibody light chains.
D. All of the above.
34. Recombinatorial diversity in antibodies refers to which of the following?
A. The possible combinations of V, D, and J segments in the heavy chain.
B. The use of both maternal and paternal alleles when synthesizing antibody.
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Biol. 456/556, Immunology
Tuesday February 8, 2018
EXAM A
First Exam, Spring Semester 2018
C. The possible combinations of different heavy and light chains.
D. The variation in the junctions between V(D)J segments.
35. Treating 7S immunoglobulin to break disulfide bonds gives rise to which of the following?
A. F(ab’)2 and smaller fragments.
B. F(ab) and F(c) fragments.
C. Intact heavy and light chains.
D. 19S immunoglobulin.
36. Attenuated strains of pathogenic organisms are best defined as?
A. A different species of organism that normally doesn't cause disease.
B. A related species of organism that is unable to stimulate cross-protective immunity.
C. Pathogens that are viruses but not bacteria.
D. A pathogen that has lost the ability to cause disease but can still stimulate immunity.
37. Landsteiner found that serum from normal, healthy people agglutinated red blood cells from some, but not
all, other humans? What can be concluded from his observations?
A. All humans have had a blood transfusion at some point in their life.
B. Humans are not tolerant to their own red blood cells.
C. Normal, healthy people produce antibodies that bind to epitopes on some red blood cells.
D. Eating lamb sometimes results in people being immune to sheep red blood cells.
38. A mouse is injected with keyhole limpet hemocyanin (KLH) as an antigen. Serum from this mouse is
collected and tested for antibodies by immunoprecipitation. Which of the following antigens should NOT
be precipitated by this serum?
A. TNP-KLH.
B. DNP-BSA.
C. KLH alone.
D. DNP-KLH.
39. Junctional diversity in antibody genes refers to which of the following?
A. The possible combinations of V, D, and J segments in the heavy chain.
B. The use of both maternal and paternal alleles when synthesizing antibody.
C. The possible combinations of different heavy and light chains.
D. The variation in the junctions between V(D)J segments.
40. The surrogate light chains on the cell surface of a developing B cell signal which of the following to occur?
A. Rearrange a D segment to a J segment at the heavy chain locus.
B. Rearrange a V segment to a D segment at the heavy chain locus.
C. Rearrange a V segment to a J segment at the light chain locus.
D. Rearrange a V segment to a C segment at the heavy chain locus.
41. Newborn goats born to non-immune mothers but nursed by immune mothers were found to have some
immunity. What is the conclusion you can draw from this observation?
A. Immune mothers transfer antigen to offspring when nursing to stimulate antibody production in the
young.
B. Immune mothers can transfer antibodies to their offspring through the milk.
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Biol. 456/556, Immunology
Tuesday February 8, 2018
EXAM A
First Exam, Spring Semester 2018
C. Non-immune mothers can still transfer specific antibody to offspring across the placenta.
D. Non-immune mothers transfer specific antibody to offspring across the placenta.
42. Which of the following results demonstrates that a Fab fragment can bind antigen?
A. It causes the antigen to agglutinate.
B. It can be removed from solution by antigen.
C. It can result in opsonization of the antigen.
D. It can be crystallized.
43. Bence-Jones proteins provided what critical piece of information to our understanding of antibody
structure?
A. Being homogenous their primary protein structure could be determined.
B. They demonstrated that antibodies protect the urinary tract.
C. They were diagnostic for patients with a thymoma.
D. They could agglutinate antigen by themselves.
44. If the antibody heavy chain locus contained 100 different germ-line V segments, 5 different germ-line D
segments, and 2 different germ-line J segments, how many different heavy chain variable regions could be
produced from one allele by recombinational diversity?
A. 100.
B. 107.
C. 1000.
D. Not enough information.
45. What happens to a B cell that fails to correctly recombine its heavy chain locus on its first try?
A. It tries to recombine the other allele of the heavy chain locus.
B. It dies immediately.
C. It tries to recombine its light chains first.
D. It goes to the thymus and becomes a T cell instead.
46. In 1960, Nossel and Lederberg demonstrated that a single isolated antibody producing cell capable of
preventing Salmonella adelaide from swimming could not do the same to Salmonella typhi. What aspect of
immunological theory did their experiment support?
A. The clonal nature of B cells.
B. The need for antigen presentation.
C. The need for self-tolerance.
D. The importance of vaccination.
47. The formation of the germinal center in the lymph node during an immune response is consistent with
which step of Burnet’s clonal selection theory?
A. Positive Selection.
B. Negative Selection.
C. Random generation of individual B cell specificities.
D. Elimination of B cells that are anti-self.
48. Based on Burnet’s clonal selection theory, why are IgG responses greater upon second exposure to an
antigen than the first exposure?
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Biol. 456/556, Immunology
Tuesday February 8, 2018
EXAM A
First Exam, Spring Semester 2018
A.
B.
C.
D.
Anti-self antibody producing cells have been eliminated by negative selection.
Self-antigens expand the number of antibody producing cells.
IgG is a smaller antibody than IgM and can be made faster.
There has been an increase in the number and frequency of cells making specific antibodies.
49. The variation in the CDR3 of the Variable domain of an immunoglobulin heavy chain protein is encoded by
what part of the heavy chain gene?
A. The junction of the V, D and J segments.
B. The D segments alone.
C. The J segment alone.
D. The V segment alone.
50. In Burnet’s clonal selection theory, what is the purpose of positive selection?
A. Positive selection is the activation of mature B cells by foreign antigens.
B. Positive selection is the removal of B cells that are anti-self early in their development.
C. Positive selection is the removal of B cells that fail to correctly rearrange their V-D-J segments.
D. Positive selection is the clonal expansion of anti-self B cells.
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