Immunology MCQ Flashcards
1. Pt presents with right iliac fossa pain; diagnosed with pyogenic inflammation of the appendix. Mediator of Innate Immunity: A. IFN Type 1 B. MBL C. IgG D. CTLs E. Eosinophils
B. MBL
- Immunoglobulin isotope switching from IgM to IgA involves
A. Activated RAG
B. Pairing with alternate light chain
C. Peptide presentation by HLA class II
D. CD4+ T cell help
E. Formation of alternate variable domain
D. CD4+ T cell help
3. Metastatic carcinoma cells are MOST likely to become lodged in which regions of the lymph node? A. Subcapular sinus B. Follicles C. Paracortex D. High endothelial venules E. Medulla
A. Subcapular sinus
4. Increased capillary permeability as a result of complement activation is MOST likely due to A) depletion of C1 B) formation of anaphylatoxins C) formation of C3b D) formation of c5 convertase E) formation of membrane attack complex
B) formation of anaphylatoxins
- Which of the following are major antigens recognized by alloreactive T cells that mediate acute graft-versus-host rejection following haematopoietic stem cell transplantation?
A. ABO blood antigen
B. Rhesus antigens
C. Tissue specific antigens not expressed in thymus
D. T cell receptor
E. Human Leukocyte Antigen
E. Human Leukocyte Antigen
6. A novel strain of influenza H7N9 has emerged. Which immune cell provides rapid first line response? A. CD4+ T lymphocyte B. CD8+ T lymphocyte C. Natural Killer Cells D. Neutrophils E. Eosinophils
C. Natural Killer Cells
- Following an immunization with Hemophilus Influenzae conjugate vaccine, which of the following is MOST likely to protect the immunized patient against severe disease when exposed to H. Influenzae?
A. CD4+ T cells specific for capsule polysaccharides
B. CD8+ T cells specific for capsule polysaccharides
C. Complement c3
D. IgM antibodies specific for capsule polysaccharides
E. IgG antibodies specific for capsule polysaccharides
E. IgG antibodies specific for capsule polysaccharides (conjugate vaccines trigger IgG production for encapsulated bacteria)
- Prior to renal transplant, mix donor’s lymphocytes with recipient’s serum. What are you checking for?
A. Donor specific antibodies in recipient serum
B. Alloreactive T cells in recipient
C. Check for anti CMV antibodies in recipient serum
D. Check for anti HIV antibodies in recipient serum
E. Recipients specific T cells in donors lymphocytes
A. Donor specific antibodies in recipient serum
- Which of the following is the most likely mechanism of protection mediated by neutralising antibodies against viruses?
A. Destruction of viruses by antibody dependent cellular cytotoxicity
B. Interferes with entry of viruses into target cells
C. Complement activation via classical pathway
D. Stimulation of type 1 interferon production
E. Antigen dependent activation of CTLs
B. Interferes with entry of viruses into target cells
- Which of the following best explains why a pregnant woman with poorly controlled Graves’ disease might be at risk of giving birth to a child with symptoms of hyperthyroidism
A. Transplacental transfer of triiodothyronine to fetus
B. Transplacental transmission of TSH to fetus
C. Transplacental transmission of pathogenic antibodies to fetus
D. Transplacental trafficking of pathogenic cd4+ T cells into fetal circulation
E. Maternal CTLs are alloreactive against fetal thyroid antigens
C. Transplacental transmission of pathogenic antibodies to fetus
- What is the most likely action of IL-4
A. Activates complement pathway
B. Neutralise allergens
C. Triggers mast cells
D. Th2 cells proliferation and differentiation
E. Binding to self antigen
D. Th2 cells proliferation and differentiation
13. Which of the following does not describe asthma correctly: A. Irreversible obstruction of airways B. Air wall edema C. Shortness of breath D. Airway hypersensitivity E. Reversible obstruction of airways
A. Irreversible obstruction of airways
14. Which of the following are used to test for immunity against Mycobacterium TB? A. Skin prick test B. Red Blood Cell Haemagglutination test C. Mantoux test D. Allergen specific IgG E. T cell assays
C. Mantoux test
15. What causes viral clearance? A. B cell B. CD4 T cell C. Eosinophils D. Cytotoxic CD8 T cell E. NK cell
D. Cytotoxic CD8 T cell
16. Which of the following cells do NOT express MHC 1? A. T cell B. Dendritic cells C. RBC D. Macrophage E. Virus-infected cells
C. RBC
17. Affinity maturation occurs in A. Primary Follicle B. Secondary Follicle C. Parafollicular cortex D. Medullary E. Trabeculae
B. Secondary Follicle (in the germinal centre of secondary follicle. Primary follicle does not have germinal center)
18. What best describes IgE action? A. Activate complement B. Neutralize antigens C. Trigger mast cells D. Activate Th2 cells E. Bind to self-antigens
C. Trigger mast cells
- An individual with blood group B was transfused with group A blood for the first time. Which following reactions is the main mechanism for hemolysis?
A. Anti-A IgM bound to A antigen to trigger membrane attack complex.
B. Anti-A IgM bound to A antigen to trigger formation of anaphylatoxins
C. Anti-A IgM bound to A antigen to trigger opsonin deposition on RBC and to be phagocytosed
D. Anti-A IgG bound to A antigen to trigger formation of membrane attack complex
E. Anti-A IgG bound to A antigen to trigger formation of anaphylatoxins
F. CD8 T cells from the recipient attack the RBCs
G. CD8 T cells from the donor cause graft vs host reaction
H. NK cells from the recipient kill the RBCs
A. Recipient Anti-A IgM bind to A antigen on donor RBCs, activating complement pathway and resulting in a membrane attack complex that lyse the RBCs.
option C / Donor RBCs activate complement pathway, causing opsonisation and eventually phagocytosis –> doesn’t cause hemoLYSIS
20. Which of the following confers protection following administration of oral vaccine against rotavirus? A. Anti-rotavirus IgA B. Anti-rotavirus IgE C. Anti-rotavirus IgG D. Anti-rotavirus IgM E. Anti-rotavirus IgD
A. Anti-rotavirus IgA
21. CD4+ T helper cells are essential for the following B cell processes except: A. Affinity maturation B. Clonal expansion C. Somatic recombination D. Formation of plasma cells E. Formation of memory cells
21. CD4+ T helper cells are essential for the following B cell processes except: A. Affinity maturation B. Clonal expansion C. Somatic recombination D. Formation of plasma cells E. Formation of memory cells
22. Which of the following is NOT associated with allergenic asthma? A. Eosinophils B. Th2 CD4 T cells C. Mast cells D. Neutrophils E. IgE
D. Neutrophils
24. Which is the least likely to involve type 2 hypersensitivity? A. Haemolytic disease of the newborn B. Diabetes C. TB D. Goodpasture’s syndrome E. Graves’ disease
C. TB (TB is type IV)
- Thymic education of T cell precursors consists of the following except:
A. Affinity maturation
B. MHC restriction
C. Negative selection of T cells that recognize self-antigens expressed by the thymus
D. Negative selection of T cells that recognize self-antigens expressed by the liver
E. Formation of regulatory T cells
A. Affinity maturation
- A woman with myasthenia gravis gave birth to a full-term baby. The baby has signs of muscle weakness. Which of the following statements regarding neonatal myasthenia gravis is most probably correct?
A. Pathogenic Ig bind to the muscarinic receptors of the neuromuscular junction
B. Pathogenic Ig has a half-life of 3 weeks
C. CD4+ T cells in the neonate are able to aid in affinity maturation of pathogenic Ig in the neonate
D. An inherited defect in self-tolerance led to activation of pathogenic CD8+ T cells that attacked the motor end-plate
E. Pathogenic Ig belong to an isotype which forms pentamers with J-chain
B. Pathogenic Ig has a half-life of 3 weeks
A not ans: wiki says myasthenia gravis involves nicotinic receptors (the nicotinic receptors are the main ones, muscarinic ones in muscle are for regulation)
- The different specificities of the immunoglobulins produced in our body is:
A. Entirely inherited from our parents
B. Due to somatic recombination occurring in the V, D and J segments of the light chain
C. Determined by both the heavy and light chain
D. Due to somatic hypermutation and isotype switching
E. Due to genetic variation of the MHC allele
C. Determined by both the heavy and light chain
B not ans: light chain doesn’t hv D segments
29. What is associated with eosinophilia? A. Bacillus in gram negative stain B. Predominance of Th1 cells C. Mammillated eggs in stools D. Owl’s eye inclusions E. Lewy bodies in CSF
C. Mammillated eggs in stools (such as fertilized eggs of Ascaris, in ascariasis)
- Which of the statements below is FALSE?
A. Molecules >=2500kDa in weight are more antigenic than smaller molecules
B. Soluble proteins are more antigenic than particulate ones
C. Complex compounds are more antigenic than simple ones
D. Denatured proteins are more antigenic than those in their natural form
E. Antigens administered subcutaneously are more antigenic than those administered systemically
B. Soluble proteins are more antigenic than particulate ones (particulate proteins are more immunogenic)
E not ans: subcutaneous = higher epitope density
- Which one of the statements was the most true about hyperacute transplantation rejection?
A. Recipient’s serum mixed with donor’s lymphocytes
B. Antibodies will activate an antibody-mediated cellular cytotoxicity by activating macrophages
C. The antibodies will activate the complement system by activating mannose binding lectin
D. Injection of thymic-inhibiting antibodies will diminish the rejection
E. Rejection occurs within minutes of transplantation
E. Rejection occurs within minutes of transplantation
B. Antibodies will activate an antibody-mediated cellular cytotoxicity by activating macrophages (MAY be an answer, online search reveals that macrophages can do ADCC though can’t confirm if this is a major mechanism of hyperacute rejection!)
33. Allergic rhinitis is not associated with the following? A. Mast cell degranulation B. IgE cross linking on effector cells C. Histamine binding on H2 D. Blood vessel dilation E. IL-4 secreted by C4+ T cell
C. Histamine binding on H2 (H1 Receptor rather than H2)
34. The process of immature T cells with some ability to recognise antigens in context of self HLA occurs in the: A. Fetal liver B. Thymus C. Lymph node D. Spleen E. Kidney F. Bone marrow
B. Thymus
note: negative selection of T cells also occurs in thymus
35. What is a feature of dendritic cell (APC) maturation? A. Upregulation of phagocytosis B. Downregulation of MHC-1 molecules C. Upregulation of B7 molecules D. Downregulation of cytokines secretion E. Chemotaxis to site of infection
C. Upregulation of B7 molecules
- Which of the following statements about microbe specific antibody levels is most likely to be true?
A. A two fold rise in microbe specific Ab levels between acute and convalescent levels is indicative of an infection
B. The lymphocyte proliferation assay is useful for detecting the presence of an infection
C. IgM levels are indicative of exposure to the microbe antigen in the distant past
D. The ELISA test makes use of anti-human antibody against microbe specific antibody to amplify the signal
E. A four-fold rise in microbe specific Ab levels is to be expected between samples taken at 3 and 4 weeks after infection begins
D. The ELISA test makes use of anti-human antibody against microbe specific antibody to amplify the signal
- Which of the following happens in chronic granulomatous disease?
A. Failure of neutrophil to kill pathogens
B. Failure of chemotaxis
C. Cell-mediated immunity defects
D. Humoral immunity defects
E. Failure of opsonisation
A. Failure of neutrophil to kill pathogens (CGD is a hereditary disease, in which neutrophils and macrophages have difficulty forming the reactive oxygen compounds (most importantly, the superoxide radical) used to kill certain ingested pathogens)
- All of the following are likely to be caused by type II hypersensitivity except:
A. Antibodies to platelets resulting in autoimmune thrombocytopenic purpura
B. Haemolytic disease of the newborn
C. Injection of antigens resulting in Arthus reaction
D. Antibodies to Ach receptor resulting in myasthenia gravis
E. Antibodies to islet cell antigens resulting in diabetes
C. Injection of antigens resulting in Arthus reaction (Typical of most mechanisms of the type III hypersensitivity, Arthus manifests as local vasculitis due to deposition of IgG-based immune complexes in dermal blood vessels)
- Which of the following is least likely to activate the complement system?
A. IgG to antigen
B. IgM to antigen
C. C reactive protein to pneumococcus
D. Mannose binding lectin binding to bacterial mannose
E. Spontaneous cleavage of C3 complement
C is ans
A. IgG to antigen (classical pathway)
B. IgM to antigen (classical pathway)
C. C reactive protein to pneumococcus
D. Mannose binding lectin binding to bacterial mannose (lectin pathway)
E. Spontaneous cleavage of C3 complement (alternative pathway)
40. What is the pattern recognition receptor for bacterial LPS? A. TLR3 B. TLR4 C. TLR7 D. Fc gamma 1 E. Complement receptor 1
B. TLR4
- Which of the following statements is likely to be false for the structure of IgG?
A. It is composed of two identical light and two identical heavy chains
B. Both the light and heavy chain form part of the antigen binding component
C. Both the light and heavy chains form part of the component that binds to complement C1qrs
D. Both heavy chains are joined by intermolecular disulphide bonds
E. Each heavy chain is stabilized by intramolecular disulphide bonds
C. Both the light and heavy chains form part of the component that binds to complement C1qrs (only Fc component of heavy chain binds to complement)
42. What type of immunoglobulin does the neonatal Fc receptor bind and transport across the placenta? A. IgA B. IgE C. IgG D. IgD E. IgM
C. IgG
43. The following molecules are expressed by cytotoxic T lymphocytes when they encounter cognate antigen on target cells and contribute to cell mediated immunity, except: A. Perforin B. Granzyme C. FAS D. IFN-alpha E. TRAIL
D. IFN-alpha (typically anti-viral, from monocytes and fibroblasts. not sure, but it could be a trick because we think of TNF-alpha and IFN-gamma but NOT IFN-alpha when looking at cytotoxic T cells)
C not ans: FAS (Fas-induced apoptosis and the perforin pathway are the two main mechanisms by which cytotoxic T lymphocytes induce cell death in cells expressing foreign antigens.)
E not ans: TRAIL = TNF-related apoptosis-inducing ligand
44. The T helper cell has many accessory cell-surface molecules to help it undergo activation. The following are all involved, except: A. CD4 B. CD20 C. CD28 D. IL-2R E. LFA-1
B. CD20
- The following are associated with dendritic cell maturation except
A. Increased phagocytosis
B. Increased expression of cell surface CD 86
C. Increased expression of cell surface MHC class 1 peptide complex
D. Migration to regional lymph nodes via afferent lymph vessels
A. Increased phagocytosis
47. Clonal lymphoid malignancies derived from a progenitor tumor cell that has undergone VDJ recombination has the recombined gene as a tumour-specific marker. Which of the following assays is the most sensitive in detecting residual disease following therapy? A. Western blot B. ELISA C. PCR D. FISH E. Flow cytometry
C. PCR
All of the following are true with respect to IgM antibodies EXCEPT which one
A. they fix complement
B. they occur on the surface of lymphocytes
C. they predominate in the primary response to antigen
D. they are glycoproteins
E. they mediate allergic reaction
E. they mediate allergic reaction
One principal function of complement is to
A. inactivate perforins
B. mediate the release of histamine
C. Bind antibodies attached to cell surfaces and to lyse these cells
D. phagocytize antigens
E. cross link allergens
C. Bind antibodies attached to cell surfaces and to lyse these cells
One principal function of the Class I and Class II major histocompatibility complex S proteins is to
A. transduce the signal to the T-cell interior following antigen binding
B. mediate immunoglobulin class switching
C. present antigen for recognition by the T-cell antigen receptor
D. stimulate production of interleukins
E. bind complement
C. present antigen for recognition by the T-cell antigen receptor
The major role of the complement system is to work in conjunction with
A. antibodies to lyse cells via the C8 and C9 components
B. the major histocompatibility complex for cell recognition
C. antibodies to opsonize cells
D. the T-cell receptor for production of lymphokines
E. antibodies to lyse cells via the perforin molecules
A. antibodies to lyse cells via the C8 and C9 components
T-cell antigen receptors are distinguished from antibodies by which of the following
A. T-cell receptors are glycosylated
B. T-cell receptors must interact with antigen uniquely presented by other cells but not with free antigen
C. T-cell receptors bind various cytokines
D. T-cell receptors bind complement to lyse cells
E. T-cell receptors are mediators of allergic reactions
B. T-cell receptors must interact with antigen uniquely presented by other cells but not with free antigen
T-cell receptors or antibodies react with antigens
A. because both are made by lymphocytes
B. because of complementary of molecular fit of both with antigen
C. because both ‘have light chain and heavy chain polypeptides
D. cause histamine release
E. facilitate perforin release
B. because of complementary of molecular fit of both with antigen
All of the following are true of antigen EXCEPT which one of the following? A. They contain epitopes. B. They will react with antibodies. C. They contain antigenic determinants. D. They can elicit an immune response. E. They contain paratopes.
E. They contain paratopes.
All of the following are true with respect to IgE molecules, EXCEPT which one?
A. They are the principal immunoglobulin class involved in allergic reactions.
B. They are involved in mediating anti-parasitic immune responses.
C. They will cross the placenta and fix complement.
D. They can effect the release of histamine and other chemical mediators.
E. They are the least abundant immunoglobulin in the serum.
C. They will cross the placenta and fix complement.
Which of the following immunoglobulins is present normally in plasma at the highest concentration? A. IgG B. IgM C. IgA D. IgD E. IgE
A. IgG
All of the following are true about antibodies, EXCEPT which one?
A. They fix complement.
B. They occur on the surface of B-lymphocyte
C. They predominate the primary immune response to antigen.
D. They are glycoproteins.
E. They are molecule with a single, defined amino acid sequence.
E. They are molecule with a single, defined amino acid sequence.
The major immunoglobulin family to which a particular immunoglobulin belongs can be determined by sequential analysis of the 110 amino acids beginning from the A. Amino terminus of the light chain. B. Carboxy terminus of the light chain. C. Amino terminus of the heavy chain. D. Carboxy terminus of the heavy chain. E. None of the above
D. Carboxy terminus of the heavy chain.