Immunology Class Exams

Spring 2010 WHITE VERSION Exam I Choose one answer for each question. Each question is worth 2.5 points (100 points total) 1) To switch from IgM to IgG, a B cells needs to change: A) the constant region of their heavy chain B) the constant region of their light chain C) their hypervariable region D) two of the above 2) Where are Hassal's Corpuscles located? A) in an area where isotype switching occurs B) in an area containing high levels of CXCL10 C) in primary lymphoid organs D) in the periarteriolar lympoid sheath E) two of the above are correct 3) What does NOT occur during septic shock? A) decrease in blood sugar levels B) an increase in blood clots C) an increase in neutrophils D) constriction (decrease in diameter) of the blood vessels 4) What occurs when a patient reaches the zone of equivalence? A) they have a high level of small immune complexes B) they have contracted a chronic infection C) they have antigen/antibody complexes that can be easily phagocytosed D) they have more IgE than any other isotype 5) If M cells transport antibodies, what type of antibodies would you expect them to transport considering their location? A) the antibody that forms dimers when it is secreted B) the antibody that causes allergies C) the antibody that binds to Fc receptors on macropahges D) the antibody that forms pentamers when it is secreted 6) Which of the following is NOT a leukocyte? A) dendritic cell B) T cell C) monocyte D) they are all leukocytes 7) Which of the following do you NOT want to act as a tolergen? A) a protein in onions B) a protein in the pancreas C) the flagella on E.coli D) a protein in the central nervous system 8) What is the difference between MHC I and MHC II? A) only one (either MHC I or MHC II) is expressed by dendritic cells B) only one (either MHC I or MHC II) is up regulated by TGF-b treatment C) only one (either MHC I or MHC II) is able to present small peptides D) none of the above are correct 1 9) To increase the affinity between an MHC molecule and a peptide, what would need to be changed? A) the b-pleated sheets on the MHC molecule B) the anchor residues on the peptide C) the non-anchor residues on the peptide D) A and B E) A and C 10) What did Edward Jenner demonstrate using James Phipps? A) the adaptive immune response B) memory NK cells C) the acute phase response D) passive immunization 11) What is the function of Langerhans cells? A) to transport antigens across the blood-brain barrier B) to transport antigens to Peyer's Patches C) to capture antigens in the alveoli D) to capture antigens in the skin 12) How are complement proteins similar to IgM? A) both complement proteins and IgM bind to opsin receptors on phagocytic cells B) both complement proteins and IgM bind to the surface of bacteria C) both complement proteins and IgM function as acute phase proteins D) both complement proteins and IgM activate NK cells 13) What do neutrophils need to extravasate? A) hydrogen peroxide B) CCR7 C) integrins D) L-selectin 14) How would you now if a patient bit by a snake was treated with passive immunization? A) the patient would have a very fast antibody response (1-2 days) to snake venom if they were bitten several years later B) the patient would have immune complexes in their blood C) the patient would have horse B cells in their blood D) more than one of the above is correct 15) A patient's haplotype includes the following gene: HLA-DRA 15 25. What do we know about this gene? A) The gene encodes a polypeptide chain that is "recognized" or binds to antibody #25 (not antibody #15) used for testing B) The gene encodes a polypeptide chain that binds directly to antigen peptides C) The gene encodes the alpha chain of a MHC I molecule D) more than one of the above are correct. 16) Which of the following properties is similar for macrophages and neutrophils? A) ability to phagocytose B) contribution to pus C) lifespan D) two of the above E) all of the above 2 17) What do we know about the HLA-B gene? A) the HLA-B gene encodes a non-polymorphic polypeptide that pairs with a non-polymorphic polypeptide B) the HLA-B gene encodes a polymorphic polypeptide that pairs with an a chain C) the HLA-B gene encodes a polymorphic polypeptide that pairs with a non-polymorphic polypeptide D) the HLA-B gene encodes a non-polymorphic polypeptide that pairs with an a chain 18) How do antigens and lymphocytes circulate through the lymph nodes? A) both antigens and lymphocytes enter the lymph nodes in efferent lymphatic vessels and leave the lymph nodes through afferent lymphatic vessels B) both antigens and lymphocytes enter through the blood vessels and leave though the lymphatic vessels C) lymphocytes enter through the blood vessels and leave through the lymphatic vessels while antigens enter and leave using lymphatic vessels D) both antigens and lymphocytes enter the lymph nodes in afferent lymphatic vessels and leave the lymph nodes through efferent lymphatic vessels 19) One of the light chain is the k light chain. What describes the correct order in which each of the following proteins are produced during B hematopoiesis? A) m, then d and finally k B) m, then k and finally d C) k, then m, then d D) k, then d, then m 20) Why are high endothelial venules (HEV) so important? A) without HEVs, the follicles in lymph nodes would be extremely small or possibly absent B) without HEVs, there would be no response to blood-borne antigens C) without HEVs, lymphocytes can not enter the blood circulation D) more than one of the above 21) Cells with high levels of CCR7 are located in the paracortex of the lymph nodes and cells with high levels of CXCR5 are located in the red pulp. A) True B) False 22) B cells differentiate into plasma cells in the secondary lymphoid tissues. A) True B) False 23) MHC molecules are more polymorphic than any of the other antigen receptors. A) True B) False 24) Lymph nodes are swollen in patients with infections due to the massive proliferation of macrophages in the lymph nodes. A) True B) False 25) The smooth muscles around blood vessels in inflamed tissues are more relaxed than the smooth muscles around blood vessels in non-inflamed tissues. A) True B) False 26) During affinity maturation mutations are made in the DNA encoding the epitope. A) True B) False 3 27) To determine if a group of B cells are activated, all you need is to watch them under a light microscope. A) True B) False 28) The HLA-A gene encodes a polymorphic a chain that pairs with a non-polymorphic polypeptide chain. A) True B) False 29) The thoracic duct is needed for red blood cells to enter the lymphatic vessels. A) True B) False 30) Activated helper T cells secrete cytokines that directly affect cells in both the myeloid and lymphoid lineage. A) True B) False 31) TLR4 activates phagocytosis after it binds to an opsin. A) True B) False 32) The polypeptide encoded by the maternal allele of the HLA-DQA gene can pair with the polypeptide encoded by the paternal allele of the HLA-DQB gene, but the polypeptide encoded by the maternal allele of the HLA-DQA gene can not pair with the polypeptide encoded by the maternal allele of the HLA-DPB gene. A) True B) False 33) An Fab fragment has more effector functions than an F(ab')2 fragment. A) True B) False 34) Macrophage activation can be measured similarly to B cell activation in that both involve several hours of cell division and a change in their antigen receptors. A) True B) False 35) Based on the brief introduction to regulatory T cells, one would expect regulatory T cells to secrete more TGF–b than TNF-a. A) True B) False 36) Mice that lack IL-7 are unable to produce lymphocytes but they are able to produce myeloid cells. A) True B) False 37) The respiratory burst occurs when phagocyte oxidase is activated. A) True B) False 38) TLR4 binds to lipopolysaccharide (LPS) and is located on the endosome membrane. A) True B) False 39) In general, pentameric IgM has a weaker avidity for monovalent antigens than monomeric IgG. A) True B) False 40) Mice that lack b2 microglobulin are unable to activate helper T cells. A) True B) False 4