Kuby Immunology Exam 5 Ch's 15-20

Annexin-V staining of cells identifies:

a failure of membrane integrity. broken ends of chromosomes produced during DNA fragmentation. necrotic but not apoptotic cells. both apoptotic and necrotic cells. a breakdown of membrane asymmetry.<-Correct!

Autoimmune diseases:

a. involve a failure of central tolerance. b. involve a failure of peripheral tolerance. c. lead to tissue destruction. d. Both A and B. e. All of the above. <-Correct!

The tolerogenic response:

a. is not antigen specific. b. leads to apoptosis but not anergy. c. results in cells becoming non-responsive. <-Correct! d. depends of the presentation context. e. affects T cells only.

Central tolerance:

a. is the first step of tolerance mechanisms. b. affects both T cells and B cells. c. deletes cells that are autoreactive. d. occurs in the bone marrow and thymus. e. All of the above. <- Correct!

Metastasis is NOT which of the following?

A property of benign tumors <-Correct! Invasion of new sites by tumor cells The production of secondary tumors A property of malignant tumors Extremely dangerous

Confocal microscopy improves on immunofluorescence in that it:

A. increases the resolution of the image. B. allows construction of three-dimensional images.<-Correct! C. allows detection of multiple molecules. D. is the only technique that allows use of living cells. E. None of the above.

Immunotoxins work by:

A. inducing apoptosis in the target cells. B. recruiting complement to kill the target cells. C. delivering chemicals specifically to the target cells.<-Correct! D. recruiting NK cells. E. None of the above.

Alpha-feto protein (AFP) is:

A. normally expressed by embryos. B. normal for pregnant women. C. expressed aberrantly by some cancers. D. Both A and C. E. All of the above. <-Correct!

Tumor-suppressor genes are NOT:

A. normally regulating cell growth. B. called anti-oncogenes. C. causes of cancer when they become inactive. D. causes of cancer when they become activated. <-Correct! E. Both A and C.

A key role for natural killer cells in controlling cancer is NOT supported by the:

A. observation that NK-deficient mice have higher than normal rates of sarcoma development. B. observation that NK cells can kill cancer cells in vitro. C. observation that many tumors down-regulate MHC genes, including NK receptors. D. observation that cellular stress up-regulates many NK receptors. <-Correct! E. All of these support the role.

Intracellular staining is a major advance in cell sorting that:

A. requires permeabilization of the cell membrane. B. allows detection of molecules inside the cell instead of simply at the cell surface. C. allows sub-cellular localization of molecules. D. Both A and B. <-Correct! E. All of the above.

Graft rejection consists of:

A. sensitization, when T cells are stimulated, and effector, when they attack the graft. <- Correct! B. sensitization, when B cells are stimulated, and effector, when they attack the graft. C. recognition, when T cells are stimulated, and effector, when they attack the graft. D. recognition, when B cells are stimulated, and effector, when they attack the graft. E. None of the above.

In flow cytometry, in addition to fluorescent markers, forward (FSC) and side (SSC) scatter are measured, and:

A. side scatter is a reflection of the size of the cell. B. forward scatter is a measure of the amount of DNA in the cell. C. side scatter is a measure of the amount of DNA in the cell. D. forward scatter is a reflection of the internal complexity of the cell. E. None of the above. <Correct Answer

Tumor-specific antigens:

A. trigger T-cell killing of the tumor. B. can be difficult to identify. C. are strongly selected against by the immune system. D. Both A and B. E. All of the above. <-Correct!

Modern-day vaccines try to elicit an immune response from:

memory B cells. cytotoxic T cells. hematopoietic stem cells. innate immune cells. naïve B cells and TH cells. <-Correct!

Responses of the immune system that can promote cancer include all of the following EXCEPT:

chronic inflammation. inhibition of Th1 responses. myeloid-derived suppressor cells (MDSCs). CTL activation. <-Correct! All of these promote cancer.

In chromium release assays, or more recently in CFSE release assays, cells that die release the marker if they:

die by apoptosis only. die by necrosis only. die by either apoptosis or necrosis.<-Correct! divide before dying. replicate DNA before dying.

Tolerance is promoted by all of the following circumstances EXCEPT:

high doses of antigen. persistent antigen. oral introduction of antigen. presence of adjuvant. <-Correct! low levels of costimulation.

The use of inbred lines of mice:

reduces genetic heterogeneity. reduces experimental variables. increases similarity between individuals. leads to syngeneic animals. All of the above.<-Correct!

Immunotherapy designed to target B-cell lymphoma with a monoclonal antibody is easier to administer than other immunotherapies because:

the lymphoma is more prone to apoptosis. an anti-idiotypic monoclonal antibody won't target bystander cells. <-Correct! the lymphoma is able to conduct class switching. the lymphoma is localized to specific organs. All of the above.

Isografts are NOT usually rejected because:

they are between genetically identical individuals. they are MHC matched. they do not trigger an immune response. they are syngeneic. All of the above. <-Correct!

The use of tumor-specific T cells re-introduced to patients requires all of the following EXCEPT:

tumor-specific cells being isolated. tumor-specific cells being activated in order to overcome tumor-induced anergy. the patient being lymphodepleted to facilitate re-introduction. tumor-specific cells being depleted of autoreactive clones.<-Correct! All of these steps are required.

Manipulation of costimulatory signals has potential to treat tumors because:

tumors that do not provide costimulation induce anergy instead. it is relatively easy to isolate and introduce genes to tumor cells. modified tumors with increased costimulatory activity can be reintroduced to patients. blockage of CTLA-4 on tumors will increase T-cell activation. Correct! All of the above.

Insulin-dependent diabetes:

usually shows juvenile onset. <-Correct! is more common in men that in women. interferes with fat metabolism. seems to be triggered by antibodies. None of the above.

Oncogenes:

were originally discovered in viruses. have been found to be normal parts of cellular function. often regulate cell growth. are mutated or disregulated in cancer. All of the above. <-Correct!

Because T cells are essential in graft rejection, nude mice, which lack a thymus:

will reject grafts the same as wild-type mice. will reject grafts more vigorously than wild-type mice. will not reject grafts since they lack T cells. <-Correct! will not reject grafts since they lack B cells. will not reject grafts because of peripheral tolerance.

What is herd immunity?

A. A global vaccination day established by the World Health Organization to ensure every person on the planet is vaccinated against a particular pathogen. The last herd immunity day was in the early 1980s with smallpox. B. A vaccination program started by progressive nations to prevent the spread of prion diseases such as Mad Cow (BSE). C. Herd immunity refers to a special vaccination method whereby immunocompromised individuals are given vaccines made only of antibodies. D. Receiving all government recommended vaccines in one day. This produces the strongest immune response possible but frequently leaves the person being vaccine experience malaise (generally feeling bad) and feverish. E. Vaccinating the majority of a population to protect immunocompromised individuals from a particular pathogen. <-Correct!

The theory that the immune system actively monitors and eliminates cancer cells is supported by the observation that:

A. AIDS patients have higher rates of some types of cancer than other populations. B. transplant patients on immunosuppressive therapy have higher rates of some types of cancer than other populations. C. patients who are deficient in adenosine deaminase and on immunosuppressive therapy have higher rates of some types of cancer than other populations. D. Both A and B. <-Correct! E. All of the above.

Carcinogens are NOT:

A. Agents that induce DNA mutations. B. agents that induce transformation. C. energy such as ionizing radiation. D. viruses such as Epstein-Barr virus. <-Correct! E. chemicals such as formaldehyde.

Sleeping sickness and Chagas's disease are caused by members of the genus Trypanosoma, protozoans that reside in the bloodstream. What is the principle way trypanosomes evade the immune response?

A. Antagonistic cytokines are produce by the trypanosome. B. Periodic changes in the surface antigen (VSG) of trypanosomes ensures that at least some cells will survive antibody mediate attacks. <-Correct! C. Trypanosomes are human pathogens and thus immune to human immune responses. D. Trypanosomes invade the brain and red blood cells so that immune effector cells such as macrophages and dendritic cells cannot phagocytize trypanosomes. E. Vaccines are readily available to people in trypanosome infested areas.

How do Plasmodium cells avoid immune clearance?

A. Antagonistic cytokines are produced by the Plasmodium cells. B. Periodic changes in the surface antigen (VSG) of Plasmodium ensures that at least some cells will survive antibody mediate attacks. C. Plasmodium cells show multi-drug resistance. D. Plasmodium invades red blood cells so that immune-effector cells such as macrophages and dendritic cells cannot phagocytize Plasmodium cells.<-Correct! E. TNF-α is produced in large amounts by Plasmodium, thus overwhelming the immune response and creating a cytokine storm.

Which of the following is an example of a passive immunization?

A. Antibodies against rabies given to someone who was bitten by a potentially rabid dog <-Correct! B. Heat-killed flu antigen grown in chicken eggs C. Live viral antigen given on a sugar cube to protect against polio D. Both A and B. E. Both B and C.

Which of the following is TRUE regarding propidium iodide and cell cycle analysis?

A. Apoptotic cells will have more DNA than normal G1 content. B. S-phase cells will have the same DNA content as G1 cells. C. G2 cells will have more DNA than normal G1 cells.<-Correct! D. M cells will have the same DNA content as normal G1 cells. E. All of the above.

By which mechanisms can bacterial pathogens evade a host immune response?

A. Avoiding phagocytosis by the production of a capsule B. Escape of the phagolysosome within phagocytic cells C. Neutralization of digestive enzymes found within phagocytic cells D. Both A and B. E. All of the above. <-Correct!

Re-emerging infectious diseases prevent a major problem worldwide. What actions can be taken to prevent the spread of re-emerging infectious diseases such as whooping cough (Bordetella pertussis)?

A. Create new antibiotics, antifungals, and antivirals to treat existing stains of pathogen and limit development of multi-drug resistances. B. Ensure proper precautions during travel, especially for airborne pathogens. C. Maintain rigorous vaccination programs for all healthy individuals. D. Provide herd immunity during outbreaks. E. All of the above are good preventative actions. <-Correct!

The major distinction between FACS and MACS is that:

A. MACS is not as precise as FACS. B. MACS does not use a fluorescent marker.<-Correct! C. MACS can be used with living cells. D. MACS can be used for intracellular staining. E. All of the above.

Anaphylatoxins stimulate a localized inflammatory response, which includes mast-cell degranulation, vasodilation, and recruitment of lymphocytes and phagocytic cells. What is the purpose of this localized immune response?

A. Mast cells contain histamine, which triggers vasodilation, which will increase blood flow to an infected area so that higher numbers of white blood cells will be recruited. B. Serum proteins contain specific and nonspecific immune effector molecules to bind up and neutralize the invading pathogen and any toxins. C. Vasodilation locally increases the temperature of an infected area so that bacterial proteins become denatured. D. Vasodilation increases tenderness at the site of infection and causes edema (swelling) to that the host is careful not to overuse or tax the infected area. E. All of the above. <-Correct!

Variability in the immune response to cancer leads to observations that:

A. NK cells and dendritic cells can control cancer cells directly. B. NK cells and dendritic cells can activate a helper T-cell response to control cancer. C. NK cells and dendritic cells can activate a cytotoxic T-cell response to control cancer.<-Correct! D. Th17 cells can activate a response to control cancer. E. All of the above.

Immunohistochemistry and immunocytochemistry differ from each other in that:

A. immunocytochemistry analyzes tissue sections. B. immunohistochemistry analyzes individual cells. C. immunohistochemistry uses electron-gold microscopy. D. Immunocytochemistry analyzes individual cells.<-Correct! E. None of the above.

Viruses, like many good pathogens, have adapted to survive in their hosts. Which of the following scenarios would be MOST favorable to viral transmission and long term survival of the viral species?

A. Virus X enters a host cell, produces many progeny viruses (virions), and lyses the host cell. B. Virus X enters the host cell and merges viral DNA with the host DNA so that the virus is copied into all progeny host cells. C. Virus X enters the host cells, merges viral DNA with the host DNA until the host cell is stressed, and then begins to produce many virions eventually lysing the host cell. D. Virus X enters the host cell and consistently makes virions at a low level so that all host cell functions are not disrupted. <- Correct! E. Virus X enters the host cell, makes many progeny virions, and releases virions through exocytosis so that each virion is wrapped in the host cell plasma membrane. The host cell will eventually die or be targeted by the immune system for apoptosis.

Carboxyfluorescein succinimidyl ester (CFSE) can be used to track cell division because:

A. after pulsing the cells with it, dividing cells will incorporate more into their DNA. B. after pulsing cells with it, dividing cells will incorporate more into their proteins. C. its intensity is cut in half, approximately, when DNA replicates. D. its intensity is cut in half, approximately, when the cell divides. <-Correct! E. None of the above.

Immunofluorescence-based imaging:

A. allows fine-scale visualization of subcellular localization. B. has been enhanced by the availability of multiple dyes. C. has been simplified by genetic engineering to tag GFP onto target proteins. D. can take advantage of molecules that do not need antibodies to bind targets. E. All of the above. <-Correct!

T cells can recognize tumor antigens from each of the following classes, EXCEPT for:

A. antigens encoded by genes exclusively expressed by tumors (e.g., viral genes). B. antigens encoded by variant forms of normal genes that are altered by mutation. C. antigens that are expressed at lower than normal levels.<-Correct! D. antigens normally expressed only at certain stages of development. E. antigens that are overexpressed in particular tumors.

ELISPOT assays:

A. are modifications of Western blotting. B. are used to detect individual cells. C. involve the use of "capture" antibodies. D. Both B and C. <-Correct Answer E. All of the above.

Tumor-associated antigens:

A. are not normal cellular proteins. B. are viral proteins. C. have abnormal expression patterns. <-Correct! D. Both A and B. E. All of the above

Most tumor antigens:

A. are products of viruses. B. target the tumor for immune recognition. C. are not recognized as self antigens. D. are oncogene products. <-Correct! E. Both B and C.

Vaccines are MOST readily made against:

A. bacteria because their cell walls remain relatively unchanged from generation to generation. <-Correct! B. fungi because several species of fungi are commensals therefore priming the immune response to readily produce antibodies to the new vaccine. C. helminths because they are large organisms and make for easy targets. D. prions because they are new microbe so there is much research effort to stop prion related diseases. E. viruses, particularly RNA viruses, because their cell receptors are unchanging and bind human cell receptors.

The major difference between benign and malignant tumors is that:

A. benign tumors are capable of metastasis. B. malignant tumors do not invade surrounding tissue. C. benign tumors are not neoplasms. D. malignant tumors are capable of uncontrolled growth. <-Correct! E. All of the above.

Viruses such as Epstein-Barr virus, cytomegalovirus, and HIV are capable of suppressing the immune system by:

A. binding antibodies but avoiding an immune response. B. infecting lymphocytes or phagocytic cells. C. production of cytokine antagonists. D. wrapping progeny viral particles in the host-cell plasma membrane. E. Both B and C. <-Correct!

Design of an effective ELISA can be challenging because:

A. different detection systems have sensitivity that ranges over five orders of magnitude. B. the number of replicates required for any ELISA is quite high. C. the anticipated concentration of targets must be estimated in order to determine the sensitivity required of the assay.<-Correct! D. signal amplification by the assay conditions can impair interpretations. E. All of the above.

You might want to use MACS instead of FACS if you:

A. have a very small number of cells to sort. B. are working with cells that are especially fragile. C. are working with a very large number of cells.<-Correct! D. need a very high degree of accuracy. E. are using multiple antibodies.

Which of the following cell types is NOT typically associated with type IV hypersensitivity reactions?

B cells <-Correct! TH1 TH17 Langerhans cells None of the above are typically associated with type IV hypersensitivity reactions.

_______ is known as an endotoxin.

C3a Capsular proteins Flagellar proteins (H antigen) Lipid A of the LPS in gram-negative cells <-Correct! Peptidoglycan in gram-positive cells

Which of the following is recognized by the innate immune system and triggers an immune response that will produce antiviral cytokines and trigger effector molecules?

Complement IgA IL-2 PAMPs <-Correct! TNF-α

Polyclonal antibodies differ from monoclonal antibodies in all ways EXCEPT which of the following:

Correct! They generally have fewer cross-reactivities. They are generally better for immunoprecipitation. They generally have lower affinity. They can vary from preparation to preparation. They differ in all of these ways.

Identification of proteins that interact with a target molecule can be done by all but which of the following mechanisms?

Electorphoretic mobility shift assay (EMSA)<-Correct! Co-immunoprecipitation Western blot analysis Micro-sequencing Yeast two hybrid system

The immune system does NOT control cancer with which of the following mechanisms?

Elimination of transforming viruses Elimination of tumor inflammation Induction of apoptosis in cancer cells Induction of anergy in cancer cells <-Correct! It uses all of these mechanisms.

Which of the following cell-surface receptors is MOST closely linked to activating type I hypersensitivity reactions?

FcεRII FcγRIIB FcεRI <-Correct! LFA-1 None of the above

The effects of histamine in allergic reactions are primarily attributable to its binding which of the following histamine receptors?

H1 <-Correct! H2 H3 H4 None of the above

Influenza virus is an annual concern in the United States and worldwide. Each year, millions of people receive the flu vaccine to protect against the influenza virus. What two viral ligands does the flu vaccine produce immunity to?

Hemagglutinin and TNF-α Hemagglutinin and N-acetyl glucosamine N-acetyl glucosamine and Neuraminidase N-acetyl glucosamine and reverse transcriptase Neuraminidase and Hemagglutinin <-Correct!

Schistomiasis is a debilitating and potentially fatal disease caused by the helminthic parasite Schistosoma. Which antibody is specific for helminth response?

IgA IgD IgE<-Correct! IgG IgM

Which maternal antigens are protective against diseases such as diphtheria, tetanus, streptococcal infections, and measles?

IgA and IgE IgA and IgG <-Correct! IgD and IgE IgG and IgM All classes of immunoglobulins

Leishmaniasis is a disease that can either be fatal to its host or will be cleared by the immune response of the host. Which pathway is responsible for clearing leishmaniasis?

Memory B cells Complement Plasma cells TC cells TH cells <-Correct!

Which of the following cell types are implicated in type I hypersensitivity reactions?

Neutrophils Mast cells/basophils <-Correct! T cells Monocytes None of the above

Which of the following is a potential cause of chronic inflammation?

Obesity Infectious agents Tissue damage Intestinal commensal microbiota components All of the above <-Correct!

Which of the following cell types are targets of the products of mast-cell degranulation, as well as the mediators produced by mast cells following degranulation?

Smooth muscle Nervous tissue Hematopoietic cells Epithelial cells All of the above <-Correct!

The tuberculin reaction is an example of which type of hypersensitivity?

Type I Type II Type III Type IV <-Correct! None of the above

Hypersensitivity reactions to penicillin have been identified that correspond to which of the above types of reactions?

Type I hypersensitivity Type II hypersensitivity Type III hypersensitivity Type IV hypersensitivity All of the above <-Correct!

The Arthus reaction is considered to be which of the following hypersensitivity types?

Type I hypersensitivity Type II hypersensitivity Type III hypersensitivity <-Correct Answer Type IV hypersensitivity All of the above

Formation of immune complexes between antibodies and soluble antigens is considered to be which type of hypersensitivity reaction?

Type I hypersensitivity Type II hypersensitivity Type III hypersensitivity <-Correct! Type IV hypersensitivity All of the above

Hypersensitivity reactions to cell surface antigens via IgG or IgM are classified as which type?

Type I hypersensitivity Type II hypersensitivity <-Correct! Type III hypersensitivity Type IV hypersensitivity All of the above

Which of the following types of hypersensitivity reactions includes the transfusion reaction?

Type I hypersensitivity Type II hypersensitivity <-Correct! Type III hypersensitivity Type IV hypersensitivity All of the above

Which of the following reactions features mast cell degranulation as one of its key features?

Type I hypersensitivity <-Correct! Type II hypersensitivity Type III hypersensitivity Type IV hypersensitivity All of the above

Which of the following types of hypersensitivity reactions is associated with IgE?

Type I hypersensitivity <-Correct! Type II hypersensitivity Type III hypersensitivity Type IV hypersensitivity All of the above

Which of the following BEST describes the difference(s) between types II and III hypersensitivity reactions?

a. Direct recognition of cell-surface antigens by antibodies in type II reactions versus deposition of improperly cleared antibody-antigen complexes in type III reactions <-Correct! b. Direct recognition of cell-surface antigens by antibodies in type III reactions versus deposition of improperly cleared antibody-antigen complexes in type II reactions c. Cross-linking of FcεRI by IgE-opsonized pathogens d. Cross-linking of FcγRIIB by IgG-opsonized pathogens e. None of the above

The transfusion reaction involves which of the following antigens that are antigenically identical to antigens on the surface of commensal bacteria?

a. Fc receptors on the surface of mast cells b. Complement receptors on the surface of APCs c. Carbohydrates on the surface of erythrocytes <-Correct! d. Fc receptors on the surface of cytotoxic cells e. None of the above

Which of the following is NOT an explanation for inefficient clearing of antibody-antigen complexes that could lead to type III hypersensitivity reactions?

a. High affinity for tissues of particular antigens b. Antigens that are prone to formation of lattices when bound by antibodies c. Highly charged antigens d. Compromised phagocytic system e. All of the above could explain inefficient clearing of antibody-antigen complexes. <-Correct!

Cytokine treatment of cancer has proven problematic because:

cytokines can show in vivo toxicity. dosages are very hard to control properly. cytokines can regulate the production of other cytokines. cytokines exert effects on a large number of target cells. All of the above.<-Correct!

Immunoediting does NOT:

lead to more aggressive tumors by natural selection. lead to elimination of tumor cells. consist of elimination, equilibrium, and escape. extend over a period of several to many years. Actually, it does all of these. <-Correct!

Acquired fungal immunity is supported by:

multiple antifungals and vaccines that are available. normal flora species that produce new antimicrobial compounds. plasma-cell and memory B-cell activation. TH1 and INF-ɣ production. <-Correct! TNF-α and TC production.