Most important MCQS Immunology Flashcards

1
Q

1- The major role of T cells includes which one of the following?

a) Recognition of epitopes presented with MHC on cells.
b) Complement fixation.
c) Phagocytosis.
d) Production of antibodies.

A

a) Recognition of epitopes presented with MHC on cells.

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2
Q

2-Megakaryocytes are minimally immunoresponsive; such cells are also known as:

a) B lymphocytes
b) T lymphocytes
c) Platelets
d) Interleukins

A

c) Platelets

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3
Q

3- A cell that kills the invading microorganisms by ADCC:

a) B lymphocytes
b) Natural killer cells
c) Cytotoxic T lymphocytes
d) T helper cells

A

b) Natural killer cells

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4
Q

4- Which one of the following is a primary lymphoid organ?

a) Thymus
b) Spleen
c) Lymph nodes
d) Tonsils

A

a) Thymus

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5
Q

5- All the following cells are antigen presenting cells EXCEPT

a) Langerhans cells
b) Dendritic cells
c) T helper-1
d) B lymphocytes

A

c) T helper-1

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6
Q

6-A cell that Does Not need MHC for antigen presentation

a) TH-1 cell
b) NK cell
c) TH-2 cell
d) Cytotoxic T lymphocyte

A

b) NK cell

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7
Q

7- CD28 molecule is found on

a) B lymphocytes
b) NK cells
c) T lymphocytes
d) Macrophages

A

c) T lymphocytes

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8
Q

8- Natural Killer cells:

a) Are important phagocytic cells
b) Are important APCs
c) Need antigen-specific MHC activation to kill abnormal cells
d) Are important in the late stages of viral infection
e) Have Fc receptors

A

c) Need antigen-specific MHC activation to kill abnormal cells

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9
Q

9-A molecule presents on all T cells and is responsible for signal transduction

a) CD1
b) CD3
c) TCR
d) CD2

A

b) CD3

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10
Q

10-The human macrophages

a) Differentiate in the thymus
b) Have IL-2 receptors
c) Have MHC antigens
d) Are activated by mitogens

A

c) Have MHC antigens

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11
Q

11- Cytotoxic T cells are involved in all of the following functions Except

a) Lysis of cells infected with viruses
b) Autoimmune diseases
c) Tumor destruction
d) Antigen presentation

A

d) Antigen presentation

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12
Q

12- T helper lymphocytes are important in augmentation of

a) Antibody production
b) Increased cytotoxicity of NK cells
c) Increase the function of macrophages
d) All of the above

A

d) All of the above

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13
Q

13- B lymphocytes differentiate into:

a) Macrophages
b) Mast cells
c) Plasma cells
d) NK cells

A

c) Plasma cells

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14
Q

14- NK cells are involved in:

a) Inflammation
b) Humoral immunity
c) Destruction of cancer cells
d) Immunotolerance

A

c) Destruction of cancer cells

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15
Q

15- CD4 and CD8 lymphocytes mature in:

a) Thymus
b) Lymph nodes
c) Thyroid gland
d) GALT system

A

a) Thymus

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16
Q

16- Antigen processing occurs in:

a) Macrophages
b) T cells
c) NK cells
d) Plasma cells

A

a) Macrophages

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17
Q

17- A molecule found on T cells and is responsible for recognition antigen

a) CD4
b) T cell receptor
c) C3
d) CD28

A

b) T cell receptor

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18
Q

18- Which of the following cytokines is secreted by T helper-1 lymphocytes?

a) IL-1
b) IL-4
c) IL-10
d) IFN-γ

A

d) IFN-γ

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19
Q

19- Which of the following cells has B7 on their surface?

a) T cells
b) Macrophages
c) NK cells
d) Mast cells

A

b) Macrophages

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20
Q

20- All of the following cells are involved in the non-specific immunity EXCEPT:

a) Neutrophils
b) Monocytes
c) B lymphocytes
d) NK cells

A

c) B lymphocytes

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21
Q

21- Myeloid lineage of the hematopoietic stem cells gives rise to all of the following cells EXCEPT:

a) Monocytes
b) T cells
c) Dendritic cells
d) Granulocytes

A

b) T cells

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22
Q

22- Which of the following surface molecules identifies B lymphocytes?

a) CD4
b) CD28
c) CD8
d) CD19

A

d) CD19

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23
Q

23- All the following describe the phagocytic cells EXCEPT:

a) They constitute the main cells of the adaptive immune response.
b) They include monocytes, macrophages, and neutrophils
c) They have CD14 as antigen binding site
d) They have MHC-II on their surfaces

A

a) They constitute the main cells of the adaptive immune response.

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24
Q

24- Macrophages perform all the following functions EXCEPT:

a) Engulf foreign material
b) Secrete cytokines
c) Form antibodies
d) Act as antigen presenting cells

A

c) Form antibodies

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25
Q

25- T lymphocytes:

a) Are not derived from bone marrow stem cells.
b) Produce antibodies.
c) Undergo maturation in the thymus.
d) Mature in lymph nodes

A

c) Undergo maturation in the thymus.

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26
Q

26- Th2 cells:

a) Are involved in antigen processing.
b) Are involved in co-stimulation.
c) Help B lymphocytes to respond to thymus dependent antigen.
d) Mucosal immunity.

A

c) Help B lymphocytes to respond to thymus dependent antigen.

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27
Q

27- Which of the following cell types is responsible for the Ag specificity of the immune response?

a) Neutrophils.
b) Lymphocytes.
c) Monocytes.
d) Basophils.

A

b) Lymphocytes.

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28
Q

28- A lymphocyte that Does Not have the CD4 or CD8 on its surface:

a) T cytotoxic cell
b) T helper cell
c) T suppressor cell
d) B cell

A

d) B cell

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29
Q

29- Cytotoxic T lymphocytes recognise foreign antigen:

a) In the context of class I MHC molecules.
b) In the context of class II MHC molecules.
c) In association with CD10.
d) In association with gamma heavy chain of IgG.

A

a) In the context of class I MHC molecules.

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30
Q

30- A monocyte in tissues is called:

a) Blood platelet
b) Mast cell
c) Macrophage
d) Natural killer cell.

A

c) Macrophage

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31
Q

31- Natural killer (NK) cells DO NOT:

a) Recognise and destroy certain tumor cells.
b) Lyse virus infected cells.
c) Require antibodies for their cytotoxic activity.
d) Display either T or B cell surface markers.

A

d) Display either T or B cell surface markers.

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32
Q

32- Which of the following cells DO NOT have Fc receptors for IgG?

a) Helper T cells
b) B lymphocytes
c) Neutrophils
d) Macrophages

A

a) Helper T cells

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33
Q

33- Which of the following tissues have over 60% B lymphocytes?

a) Peripheral blood
b) Spleen
c) Lymph nodes
d) Thymus

A

b) Spleen

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34
Q

34- The site of B cell development in mammals is:

a) The bone marrow
b) The bursa of Fabricus
c) The thymus
d) The lymph nodes
e) The spleen

A

a) The bone marrow

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35
Q

1- A substance that can evoke an immune response is termed a (an):

a) Immunogen
b) Hapten
c) Epitope
d) Adjuvant

A

a) Immunogen

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36
Q

2- A hapten:

a) Is usually a high molecular weight substance.
b) Acts as an antigen if coupled to a protein molecule.
c) Is capable of inducing immune response alone.
d) Determines specificity of an antigen.

A

b) Acts as an antigen if coupled to a protein molecule.

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37
Q

3- IgA is characterized by the following EXCEPT:

a) It provides immunity at mucosal surfaces.
b) It is a dimer in secretions.
b) It can cross the placental barrier.
d) It is found as a monomer in serum.

A

b) It is a dimer in secretions.

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38
Q

4- Which one of the following statements regarding super-antigens is true?

a) Staphylococcal toxic shock syndrome is an example of super-antigen associated disease.
b) Super-antigens are presented by antigen-presenting cells in identical manner to conventional antigens.
c) In humans, a super-antigen reacts with few numbers of T cells.
d) Superantigens activate large numbers of B cells.

A

a) Staphylococcal toxic shock syndrome is an example of super-antigen associated disease.

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39
Q

5- Superantigens:

a) Are processed inside antigen presenting cells.
b) Lead to development of memory T cells.
c) Stimulate an acquired immune response.
d) Lead to release of huge amount of non-beneficial cytokines.

A

d) Lead to release of huge amount of non-beneficial cytokines.

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40
Q

6- The following fragments are seen when IgG is split by papain:

a) Two monovalent fractions with antibody activity (Fab).
b) Two fractions devoid of antibody activity.
c) Fab fragments that contain the variable (V) domains of heavy chain but not the light chain.
d) Fab fragments that contain the variable (V) domains of the light chain not the heavy chain.

A

a) Two monovalent fractions with antibody activity (Fab).

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41
Q

7- The portion of the antibody molecule that bind antigenic epitopes is :

a) Termed the determinant.
b) Composed of variable and constant regions of Ig heavy and Ig light chains.
c) Composed of the variable regions of Ig heavy and Ig light chains.
d) The Fc fragment.
e) Two Ig light chains.

A

c) Composed of the variable regions of Ig heavy and Ig light chains.

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42
Q

8- The monoclonal antibody is characterized by the following EXCEPT:

a) Highly specific.
b) Produced by different clones of B cells.
c) Can be artificially produced.
d) Can be used in diagnosis.
e) Can be used in therapy.

A

b) Produced by different clones of B cells.

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43
Q

9- Which of the following statements is NOT TRUE about haptens?

a) Haptens elicit immune response.
b) Nickel is an example.
c) Haptens react with specific antibodies.
d) Haptens bind to tissue proteins.

A

a) Haptens elicit immune response.

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44
Q

10- Which one of the following best describes immunoglobulin structure?

a) There is little flexibility in the hinge region between Fc and Fab portion.
b) IgM is monomeric structure.
c) The amino acid sequence variation of the heavy chain is different from that of the light chain.
d) J chain is present in all Ig classes

A

c) The amino acid sequence variation of the heavy chain is different from that of the light chain.

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45
Q

11- Which of the following is the immunoglobulin that is found in acute infection and is present as a monomer on B cells but a pentamer in serum?

a) IgG
b) IgA
c) IgD
d) IgM

A

d) IgM

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46
Q

12- The part of the immunoglobulin that recognizes the antigen is called:

a) The Fab region
b) The hinge region
c) The Fc region
d) The secretory piece

A

a) The Fab region

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47
Q

13- All the following describe T-dependent antigen EXCEPT:

a) Simple structure
b) Stimulate all classes of antibodies
c) Stimulate T & B lymphocytes
d) Stimulate memory cells

A

a) Simple structure

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48
Q

4- Which one of the following properties DOES NOT describe the Immunogen?

a) Foreign
b) Reacts with MHC
c) Of low molecular weight
d) Complex structure

A

c) Of low molecular weight

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49
Q

15- IgA antibody is the first line of defense against infections at the mucous membrane. Which of the following statements is NOT TRUE for IgA?

a) IgA is not found in saliva, thus detection of IgA in saliva has no diagnostic value
b) Ig A is present in colostrum
c) IgA has two subclasses
d) IgA gives protection to intestine

A

a) IgA is not found in saliva, thus detection of IgA in saliva has no diagnostic value

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50
Q

16- Which immunoglobulin has no known function but is present on the surface of B cells and acts as antigen receptor

a) IgG
b) IgD
c) IgM
d) IgE

A

b) IgD

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51
Q

17- A good clinical example of the cross reaction phenomenon is:

a) Rheumatoid arthritis
b) Gastroenteritis
c) Acute rheumatic fever
d) Puerperal sepsis

A

c) Acute rheumatic fever

52
Q

18- Which immunoglobulin mediates immediate hypersensitivity & is involved in parasitic Infections

a) IgA
b) IgE
c) IgM
d) IgD

A

b) IgE

53
Q

19- A type of antigen that is highly toxic and binds to outside of the MHC and TCR

a) Alloantigen
b) Heterophile antigen
c) Superantigen
d) Isoantigen

A

c) Superantigen

54
Q

20- The predominant antibody of a secondary immune response is:

a) IgG
b) IgD
c) IgM
d) IgE

A

a) IgG

55
Q

21- The antibody that is composed of pentamer:

a) IgG
b) IgD
c) IgM
d) IgE

A

c) IgM

56
Q

22- The antibody that crosses the placenta and gives protection to the baby

a) IgG
b) IgD
c) IgM
d) IgE

A

a) IgG

57
Q

23- The chemical nature of T-dependent antigens is:

a) Polysaccharides
b) Proteins
c) Nucleic acids
d) Lipids

A

b) Proteins

58
Q

24- All the following describe T-independent antigen EXCEPT:

a) Simulates B lymphocytes without help of T cells
b) Stimulates all classes of antibody
c) Does not stimulate memory cells
d) Polysaccharide in nature

A

b) Stimulates all classes of antibody

59
Q

25- Which one of the following statements about rheumatic fever is true?

a) It is a complication of beta-haemolytic streptococcal infection.
b) It only affects the elderly.
c) It complicates 3% of acute sore throats.
d) It shows no evidence of genetic susceptibility.

A

a) It is a complication of beta-haemolytic streptococcal infection.

60
Q

26- The antigen that is responsible for the Cross reaction phenomenon is called:

a) Heterophile antigen
b) Superantigen
c) T-dependent antigen
d) Immunogen

A

a) Heterophile antigen

61
Q

27- Which of the following functions of antibody is due to the Fab region:

a) Killing the microbe by ADCC
b) Activation of complement system
c) Recognition and binding of antigens
d) Cross placenta

A

c) Recognition and binding of antigens

62
Q

28- The Ig that has the highest concentration in serum is:

a) IgG
b) IgD
c) IgM
d) IgE

A

a) IgG

63
Q

29- Monoclonal antibodies are produced by fusion of which of the following cell types with myeloma cells to form a hybridoma:

a) Monocytes
b) Plasma cells
c) Liver cells
d) None of these

A

b) Plasma cells

64
Q

30- The antigen binding site of an IgM is formed primarily by:

a) The constant regions of heavy and light chains.
b) The variable regions of heavy and light chains.
c) The variable regions of heavy chains.
d) The variable regions of light chains.

A

b) The variable regions of heavy and light chains.

65
Q

31- The sites on the antigen which elicit immune responses and react with antibodies:

a) Agglutinogens
b) Precipitinogens
c) Antigenic determinants
d) Agglutinins

A

c) Antigenic determinants

66
Q

32- The Paul Bunnell antigen is present in:

a) Beef heart
b) Proteus antigen
c) Human erythrocytes
d) Horse red blood cells

A

d) Horse red blood cells

67
Q

33- When two proteins contain the same antigenic determinant site:

a) A cross reaction occurs
b) a homologous serum can be prepared
c) A heterologous serum can be prepared
d) Preparation of monoclonal antibodies

A

a) A cross reaction occurs

68
Q

34- Some bacterial exotoxins are:

a) Involved in co-stimulation
b) Superantigens
c) Destroyed by NK cells
d) Involved in the action of TH-1

A

b) Superantigens

69
Q

35- The antigen which is involved in the diagnosis of syphilis is obtained from:

a) Beef heart
b) Guinea pig serum
c) Proteus
d) Sheep red blood cells

A

a) Beef heart

70
Q

36- Antibodies to what antigen is the basic cause of rheumatic fever:

a) Cardiolipin antigen
b) Forssmann antigen
c) Paul Bunnell antigen
d) Membrane antigen of streptococcus

A

d) Membrane antigen of streptococcus

71
Q

37- The antibody that reacts with a small soluble antigen:

a) Agglutinin
b) Heterophile
c) Precipitin
d) Agglutinogen

A

c) Precipitin

72
Q

38- The antigen for the Weil-Felix reaction is obtained from:

a) Proteus
b) Cardiolipin
c) Horse red blood cells
d) Streptococci antigen

A

a) Proteus

73
Q

39- An antigen determinant (epitope) refers to:

a) The variable region of the Ig molecule that has specificity for a given antigen
b) The Fc portion of the Ig molecule that binds to the Fc receptor
c) The part of the antigen that is recognized by antibody.
d) Part of the constant region of an Ig molecule that binds complement.

A

c) The part of the antigen that is recognized by antibody.

74
Q

40- Haptens are different from antigens because:

a) Haptens can induce antibody responses by themselves.
b) Haptens induce only IgM responses whereas antigens induce both IgM & IgG
c) Haptens induce neutralizing antibody responses & antigens induce agglutinating antibody responses.
d) Haptens can only induce immune responses when they are conjugated to a carrier.

A

d) Haptens can only induce immune responses when they are conjugated to a carrier.

75
Q

1- Complement is a series of host proteins which provide protection from pathogens. Which one of the following describes complement:

a) Complement inhibit phagocytosis
b) Complement plays a minor role in inflammation
c) Complement is activated by IgG and IgM
d) Bacteria are agglutinated in presence of complement but do not lyse

A

c) Complement is activated by IgG and IgM

76
Q

2- C3b is:

a) Chemotactic
b) Anaphylatoxin
c) Opsonizes bacteria
d) The inactive form of C3

A

c) Opsonizes bacteria

77
Q

3- The classical pathway for complement activation is initiated by:

a) A foreign polysaccharide
b) C5 - C9
c) An antigen-antibody reaction
d) Factors released from phagocytes

A

c) An antigen-antibody reaction

78
Q

5- The presence of C5a results in:

a) Opsonization
b) Chemotaxis of phagocytes
c) Endotoxic shock
d) Activation of NK cells

A

b) Chemotaxis of phagocytes

79
Q

8- All the following complement components are required in the alternative pathway EXCEPT

a) C1, C2, C4
b) C5, C6, C7
c) C3
d) Properdin

A

a) C1, C2, C4

80
Q

10- C5a stimulates neutrophils to do all the following EXCEPT:

a) Migration
b) Adherence to endothelium of vessels
c) Trigger an oxidative burst
d) Release interleukin-1

A

d) Release interleukin-1

81
Q

11- The binding site for complement on the IgG molecule is

a) VL domain
b) CL domain
c) CH2 domain
d) VH domain

A

c) CH2 domain

82
Q

12- The complement system plays a key role in the host defense process. Which component is the most important in chemotaxis?

a) C1q
b) C6
c) C3b
d) C5a

A

d) C5a

83
Q

3- Factor I is a serum enzyme that shows which of the following activities

a) Enhance opsonization
b) Enhances immune adherence
c) Inactivates anaphylatoxin
d) Cleaves C3b

A

d) Cleaves C3b

84
Q

16- Defects in the complement system could result in:

a) Marked increase in bleeding time
b) Impaired elimination of microbial antigens and circulating immune complexes
c) Increased resistance to viral antigens
d) Failure to produce complement fixing antibody

A

b) Impaired elimination of microbial antigens and circulating immune complexe

85
Q

23- Immune complexes that contain C3b or C4b adhere to cells that possess:

a) Class I MHC antigens
b) Class II MHC antigens
c) Complement receptors
d) All of the above

A

c) Complement receptors

86
Q

24- Lysis of bacteria by specific Ab is accurately described as;

a) Requiring only late complement components (C5 – C9)
b) Seen most frequently with G +ve organisms containing thick capsules
c) Seen most frequently with bacilli than with cocci
d) Requiring both early and late complement components

A

d) Requiring both early and late complement components

87
Q

27- Alternative pathway of complement activation is triggered by:

a) Antigen antibody complex
b) Endotoxin and cobra venom
c) C1q
d) Proteins

A

b) Endotoxin and cobra venom

88
Q

2- What is the characteristic of the adaptive immune response and not of the innate response?

a) Physical barriers
b) Chemical barriers
c) Clonal expansion of the effector cells
d) Inflammatory mediators
e) Phagocytosis

A

c) Clonal expansion of the effector cells

89
Q

3- Which of the following statements about NK cells is true?

a) They lack granules in their cytoplasm
b) They lack Fc receptors in their membrane
c) They secrete interleukin (IL)-1
d) They kill malignant cells by inducing perforation in the target cell membrane.

A

d) They kill malignant cells by inducing perforation in the target cell membrane.

90
Q

4- Which statement about the primary immune response is NOT TRUE?

a) Requires two signals for activation T lymphocytes
b) Produces effector T cells
c) Produce memory T cells
d) Produces naïve T cells

A

d) Produces naïve T cells

91
Q

6- An important defense function of Tc cells in viral infection is to:

a) Lyse virus infected cells
b) Produce cytokines
c) Neutralize free virus particles
d) Block cell respiration
e) Lyse viral capsid.

A

a) Lyse virus infected cells

92
Q

7- Development of Th1 cells is promoted by:

a) IL-12
b) IL-4
c) Large doses of antigen
d) a & c
e) b & c

A

d) a & c

93
Q

8- Development of Th2 cells is promoted by:

a) IL-4
b) Small doses of antigen
c) Both of the above
d) Neither of the above

A

c) Both of the above

94
Q

9- The primary role of Th-2 cells is to:

a) Function as T killer cells
b) Activate macrophages
c) Activate NK cells
d) Function as antigen presenting cells
e) Activate B cells

A

e) Activate B cells

95
Q

10- Activation of naïve mature B cells requires the following EXCEPT:

a) Surface antibody contact with antigen
b) T cell cytokine stimulation
c) B cell CD40 interaction with T cell CD40L
d) Expression of IgM and IgD
e) Antigen presentation to T cell via class I MHC.

A

e) Antigen presentation to T cell via class I MHC.

96
Q

12- Regarding the primary immune response:

a) There is a very short induction (lag) period.
b) Immunoglobulins produced are mainly of IgM class.
c) The induced antibody level is very high.
d) It is the first response of innate immunity.

A

b) Immunoglobulins produced are mainly of IgM class.

97
Q

16- Both cytotoxic T cells (CTLs) and natural killer cells (NK) kill tumor cells but they differ in that:

a) CTLs require MHC class I antigen for target cell recognition; NK cells do not.
b) CTLs require MHC class II antigen for target cell recognition; NK cells do not.
c) NK cells require MHC class I antigen for target cell recognition; CTLs do not.
d) CTLs do not have large azurophilic granules, NK cells have.

A

a) CTLs require MHC class I antigen for target cell recognition; NK cells do not.

98
Q

19- The following are non-specific soluble circulating defence factors that contribute to innate immunity EXCEPT:

a) Complement components.
b) Antibody.
c) Lysozyme.
d) Acute phase proteins.

A

b) Antibody.

99
Q

25- Monocytes/macrophages:

a) Have killing activity against bacteria in the extracellular compartment.
b) Require extracellular Mg++ for optimal killing.
c) Are not responsive to T cell cytokines.
d) Lack Fc receptors.

A

a) Have killing activity against bacteria in the extracellular compartment.

100
Q

26- Which of the following statements is true concerning NK cells?

a) They belong to T cell lineage.
b) They belong to B cell lineage.
c) They kill free bacteria.
d) They display cytotoxic effect on tumor cells.

A

d) They display cytotoxic effect on tumor cells.

101
Q

27- All of the following statements about macrophages are true EXCEPT:

a) They are activated by CD4+ T cells
b) They secrete IL1
c) LPS does not activate macrophages
d) They can exhibit MHC II proteins

A

c) LPS does not activate macrophages

102
Q

28- Cells which are considered the first line of defense:

a) Cytotoxic T lymphocytes
b) Th1
c) Th2
d) NK cells

A

d) NK cells

103
Q

35- A receptor on dendritic cell that recognises LPS is:

a) TLR
b) MHC-I
c) MHC-II
d) Fc receptor

A

a) TLR

104
Q

46- B cells can switch classes of antibodies (e.g. from IgM to IgG). Such switches involve change in:

a) Variable regions of H and L chains.
b) Constant regions of H chain.
c) Constant regions of L chain.
d) Constant and variable regions of H chain.

A

b) Constant regions of H chain.

105
Q

51- The secondary Humoral immune response is characterised by:

a) Longer lag phase.
b) Longer persistence of IgM synthesis.
c) Longer persistence of IgG synthesis.
d) Lower rate of IgG synthesis.

A

c) Longer persistence of IgG synthesis.

106
Q

53- Initiation of T cell proliferation during IR involves:

a) Antigen recognition.
b) Production of IL-1 by antigen presenting cell.
c) Release of IL-2 by T cells.
d) All of the above.

A

d) All of the above.

107
Q

54- Antigen receptors of B lymphocytes are:

a) MHC class I molecules.
b) MHC class II molecules.
c) MHC class III molecules.
d) Immunoglobulin molecules.

A

d) Immunoglobulin molecules.

108
Q

58- Extracellular bacteria are killed by:

a) Phagocytosis and complement
b) Apoptosis induced by cytotoxic T cells
c) C reactive protein
d) Histamine released by mast cells.

A

a) Phagocytosis and complement

109
Q

59- Memory B lymphocytes:

a) Will occasionally differentiate into plasma cells
b) Will occasionally differentiate into B lymphocytes
c) Cause the formation of stem cells.
d) Cause the formation of NK cells.

A

a) Will occasionally differentiate into plasma cells

110
Q

61- The main advantages of passive immunity over active immunity is that:

a) It can be administered orally.
b) It provides antibodies more rapidly.
c) Antibody persists for a longer period.
d) It contains primarily IgM.

A

b) It provides antibodies more rapidly.

111
Q

67- A cytokine which has a role in the switch to a Th2 response is:

a) IL-1
b) IL-12
c) IL-4
d) Gamma interferon

A

c) IL-4

112
Q

1- A cytokine which has a role in the switch to Th1:

a) IL-1
b) IL-12
c) IL-4
d) IL-7

A

b) IL-12

113
Q

2- Cytokine that causes stimulation of production of other IL-2 is:

a) Interleukin 1
b) Interleukin 4
c) Interleukin 8
d) Interleukin 10

A

a) Interleukin 1

114
Q

3- A cytokine which causes the macrophage to move to the site of immune reaction:

a) Mitogenic factor
b) Chemotactic factor
c) Inhibition factor
d) Static factor

A

b) Chemotactic factor

115
Q

4- IL-2:

a) Produced mainly by CD4 T cells
b) Produced by fibroblast
c) Produced by leukocytes in cell culture
d) Produced mainly by macrophages

A

a) Produced mainly by CD4 T cells

116
Q

5- IL-1:

a) Produced mainly by CD4 T cells
b) Produced by fibroblast
c) Produced by leukocytes in cell culture
d) Produced mainly by macrophages

A

d) Produced mainly by macrophages

117
Q

6- All the following statements are true concerning interferon-γ EXCEPT:

a) It is produced by T cells in the CMI response
b) It is a glycoprotein
c) It has a high molecular weight
d) It enhance the macrophage function

A

c) It has a high molecular weight

118
Q

7- A cytokine that is called growth factor for lymphocytes:

a) IL-2
b) IL-4
c) IL-6
d) IL-10

A

a) IL-2

119
Q

9- Redundancy of cytokines means:

a) Some cytokines act against each other
b) Cytokines act together to enhance each other
c) Different cytokines have the same activity
d) Some cytokines produce their effect on the neighboring cells

A

c) Different cytokines have the same activity

120
Q

10- All are true concerning cytokines EXCEPT:

a) They are peptides mediators
b) Produced by cells of immune system & affect many other cells
c) They are specific to antigens
d) They act at very low concentration

A

c) They are specific to antigens

121
Q

11- A Cytokine does NOT mediate or regulate the innate immune response:

a) IL-1
b) IL-10
c) IL-12
d) TNF

A

b) IL-10

122
Q

14- All are proinflammatory cytokines EXCEPT:

a) IL-1
b) IL-12
c) IL-2
d) TNF

A

c) IL-2

123
Q

16- All he following cytokines are produced by TH-2 & promote the humoral immunity EXCEPT:

a) IL-2
b) IL-4
c) IL-6
d) IL-5

A

a) IL-2

124
Q

17- A cytokine that promote the production of IgE:

a) IL-2
b) IL-4
c) TNF
d) IFN-γ

A

b) IL-4

125
Q

18- One statement is NOT true concerning IFN-α:

a) It inhibit viral replication
b) Increase expression of MHC-I
c) Inhibit cell proliferation
d) Promote humoral immunity

A

d) Promote humoral immunity

126
Q

19- A cytokine that promote viral eradication:

a) Type-I interferon
b) Tumor necrosis factor
c) Interleukin-4
d) Interferon-γ

A

a) Type-I interferon