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University of Guelph

Department of Molecular and Cellular Biology MICR3230: Final Examination, Fall Semester, 2013

December 5, 2013; 14:30 – 16:30 Seating Arrangements:

Location Last Name ROZH 102 SHI-ZZZ ROZH 104 AAA-SHA

Examiners: Drs. Bonnie A. Mallard and Azad K. Kaushik

Name:

Instructions: 1. Please write your name and ID No., exactly as on class list, on top of each page and the computer score sheet. Submit both the examination booklet (Total Pages: 15) Scantron. 2. Answer all 90 questions (One mark for each question) by choosing 3. For multiple choice questions, choose one most appropriate or best answer. 4. Mark each of your choice of answer(s) both on the examination question sheet and appropriate spot on the test-scoring sheet. 5. You are not allowed to leave the examination hall before half time or during last 15 minutes. 6. You are not allowed to use programmable calculators, wallet/purses, cell phones, palm pilots, blackberries etc. or any other such aid. 7. Please show your student ID card upon asking. 8. Please bring any matter of concern, including suspected case of academic misconduct on the part of invigilators, to the attention of either Dr. A. Kaushik or Dr. B. Mallard. 9. Please ask the instructors only genuine and fair questions. 10. Do not forget to sign the attendance card and the signature sheet.

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Section I

1. The following is a multiple choice question, select the best answer. Based on the diagram below which of the statements is true:

A) This cell is from a human antigen-presenting cell and displays 3 MHC class I alleles and 8 MHC class II alleles.

B) This cell is from a mouse antigen-presenting cell and displays 3 MHC class I alleles and 8 MHC class II alleles.

C) This cell is from a mouse antigen-presenting cell and displays 6 MHC class I alleles and 8 MHC class II alleles.

D) This cell is from a mouse antigen-presenting cell and displays 2 parental MHC haplotypes.

E) Two of the above are correct. F) None of the above are correct.

2. Answer the following as either true (A) or false (B). 1. Class I MHC molecules associate in a complementary way with the constant regions of CD4 differentiation antigens. ______ 2. Tolerance is specific unresponsiveness to an antigen. ______ 3. T-cells in nude mice do not undergo thymic clonal deletion. ______ 4. Cytokines are small molecular weight proteins that are important in regulating the immune response and they are considered non-antigen specific. _______ 5. Superantigens can cause a cytokine storm because they activate many T-cell clones. _______ 3. Match these statements with the most appropriate answers listed below. Each letter may be used once, more than once, or not at all. A) Interferon alpha and beta. _____ B) DiGeorge Syndrome. _____

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C) Down regulation of MHC. _____ D) HIV-AIDS. _____ E) NK cells. ______ 1. Antiviral activity. 2. Viral escape. 3. Cytotoxicity. 4. CD4+ T-cells. 5. Thymic aplasia.

4. The following peptides (shown using the amino acid letter codes) were eluded from HLA-A and HLA- DR molecules:

1. H3N-V-G-P-Q-K-N-E-N-L-COO 2. H3N-R-R-I-K-K-V-I-K-F-P-L-W-S-K-R-S-R-R-COO 3. H3N-S-G-R-K-A-I-A-N-L-COO 4. H3N-S-Y-F-P-E-I-T-H-V-COO 5. H3N-R-R-I-K-E-I-V-K-K-S-L-F-V-V-G-G-V-P-E-R-E-L-G-COO Which of the following statements are likely true concerning these peptides? A) Peptides 1, 3, and 4 were eluted from HLA-A. B) Peptides 2 and 5 were eluted from HLA-A. C) Peptides 2 and 5 were eluted from HLA-DR. D) Peptides 1 and 3 were more likely eluted from the same allele than peptides 1 and 4. E) A, C, and D answers are correct.

5. Consider the following problem and select the most appropriate answers. This question will require some real thinking: see figure 10-8 in the text book for help if you get stuck but not until you’ve thought about it carefully first! You have a CD8+ CTL clone from an H-2b mouse that has a T-cell receptor specific for an antigen, known as H-Y antigen, that only occurs in males. You clone the alpha/beta T-cell receptor genes from this T-cell and use them to prepare transgenic mice with the H-2b or H-2d haplotype. For each transgenic mouse listed in the table below indicate whether the mouse would (A) or would not (B) have immature double-positive and mature CD8+ thymocytes bearing the transgenic T-cell receptor.

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Transgenic Mouse

Immature double positive thymocytes

Mature CD8+ thymocytes

H-2b female

H-2b male

H-2d female

H-2d male

Section II Question. Provide the most appropriate one response, by encircling the corresponding letter, for the following statements. (1) Activation of complement is a property of which antibody region:

A: Variable B: Fab C: antigen-combining site D: Constant E: Hinge

(2) A plasma cell secretes:

A: Antibody of identical specificity to that on the surface of the parent B cell B: Antibody of two antigen specificities C: The antigen it recognizes D: Many different types of antibody E: Lysozyme

(3) The secondary, but not the primary, immune response is based on: A: Memory B: The bonus effect of multivalency C: Complement activation D: Mast cell degranulation E: Enhanced phagocytosis by macrophages

(4) The main Ig in the seromucous secretions defending the external body surfaces is:

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

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Answer questions 5 based on the following diagram of an organ of the immune system:

5. The above lymphoid organ is important in:

A: haematopoesis B: antigen filtration in tissues C: monocyte production D: none of the above E: all of the above

Questions 6-7: Choose or match the best answer from choices a to e

6. IgE a. Mast cell b. Macrophage c. T cell d. NK cell e. Neutrophil

7. ADCC a. TcR b. NK cell c. Macrophage d. Neutrophil e. TH2