Brainscape's Knowledge GenomeTM

Browse over 1 million classes created by top students, professors, publishers, and experts.


See full index

IMMUNOLOGY & SEROLOGY (TopnotcherQT) > ANTIBODIES > Flashcards

ANTIBODIES Flashcards

memorization

1
Q

Specific glycoproteins referred to as immunoglobulins; produced in response to antigenic stimulation

A

Antibodies

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

Enumerate functions of immunoglobulins:

A
  1. Neutralize toxic substances
  2. Facilitate phagocytosis through opsonization
  3. Kill microbes
  4. Combine with Ag on cell surfaces and thereby cause destruction of cells
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

This type of bond connects a heavy chain to heavy chain and heavy chain to light chain.

A

Disulfide bonds

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

A light chain-to-light chain connection is seen in:

A

Bence Jones Protein

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

The hinge region is located between ______ and _________.

A

Constant Heavy chain 1 (CH1) and Constant Heavy chain 2 (CH2)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

This immunoglobulin region allows the Ig to take on different shapes:

A

Hinge region

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

High _______ content gives the Immunoglobulin flexibility

A

Proline

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

How many domains do IgM and IgE have?

A

5 domains

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

How many domains do IgG, IgA, and IgD have?

A

4 domains

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

Light chain antiboy molecules:

A

Kappa
Lambda

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

Heavy chain antibody isotypes:

A

Mu (IgM)
Gamma (IgG)
Alpha (IgA)
Delta (IgD)
Epsilon (IgE)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

The first approximately 110 amino acids at the amino-terminal end constitute the _______ domain:

A

Variable domain

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

Valence in immunoglobulins refers to:

A

number of binding sites

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

Monomer immunoglobulin has ____ binding sites:

A

2 binding sites

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

Dimer immunoglobulins has ____ binding sites:

A

4 binding sites

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

Pentameric IgM has ____ binding sites:

A

10 binding sites

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

Which of the following is a characteristic of variable domains of immunoglobulins?

a. They occur on both the H and L chains.
b. They represent the complement-binding site.
c. They are at the carbox-terminal ends of the molecules
d. They are found only on H chains

A

a. They occur on both the H and L chains

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

All of the following are true of IgM except that it

a. can cross the placenta
b. fixes complement
c. has a J chain
d. is a primary response antibody.

A

a. can cross the placeta

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

How does the structure of IgE differ from that of IgG?

a. IgG has a secretory component and IgE does not.
b. IgE has one more constant region than IgG
c. IgG has more antigen-binding sites than IgE
d. igG has more light chains than IgE

A

b. IgE has one or more constant region than IgG

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

How many antigen-binding sites does a typical IgM molecule have?

a. 2
b. 4
c. 6
d. 10

A

d. 10

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
21
Q

Bence Jones Proteins are identical to which of the following?

a. H chains
b. L chains
c. IgM molecules
d. IgG molecules

A

b. L chains

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
22
Q

A Fab fragment consists of

a. two H chains
b. two L chains
c. one L chain and one-half of an H chain
d. one L chain and an entire H chain

A

c. one L chain and one-half of an H chain

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
23
Q

Which antibody best protects mucosal surfaces?

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

A

a. IgA

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
24
Q

Which of the following pairs represents two different immunoglobulin allotypes?

a. IgM and IgG
b. IgM1 and IgM2
c. Anti-human IgM and anti-human IgG
d. IgG1m3 and IgG1m17

A

d. IgG1m3 and IgG1m17

  • IgM and IgG (option a) are different classes of immunoglobulins, not allotypes.
  • IgM1 and IgM2 (option b) are subclasses, not allotypes.
  • Anti-human IgM and anti-human IgG (option c) are antibodies against different immunoglobulins, not allotypes.
  • IgG1m3 and IgG1m17 (option d) represent different allotypes of the IgG1 subclass, varying in their genetic markers (m3 and m17).
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
25
Q

The structure of a typical immunoglobulin consists of which of the following?

a. 2L and 2H chains
b. 4L and 2H chains
c. 4L and 4H chains
d. 2L and 4H chains

A

a. 2L and 2H chains

A typical immunoglobulin (antibody) has:
2 Heavy Chains (H)
2 Light Chains (L)

This structure is often represented as: H2L2

  • Heavy chains (H): 2 identical chains, each consisting of:
    • 1 variable region (VH)
    • 3-4 constant regions (CH1, CH2, CH3)
  • Light chains (L): 2 identical chains, each consisting of:
    • 1 variable region (VL)
    • 1 constant region (CL)
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
26
Q

Which of the following are L chains of antibody molecules?

a. Kappa
b. Gamma
c. Mu
d. Alpha

A

a. Kappa

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
27
Q

If the result of serum protein electrophoresis show a significant decrease in the gamma band, which of the following is a likely possibility?

a. Normal response to active infection
b. Multiple Myeloma
c. Immunodeficiency disorder
d. Monoclonal gammopathy

A

c. Immunodeficiency disorder

  • Normal response to active infection (a): Typically, gamma globulins increase in response to infection.
  • Multiple Myeloma (b): Characterized by an increase (M-protein spike) in the gamma band, not a decrease.
  • Immunodeficiency disorder (c): Conditions like hypogammaglobulinemia, agammaglobulinemia, or combined immunodeficiency lead to decreased immunoglobulin production.
  • Monoclonal gammopathy (d): Typically presents with an increase (M-protein spike) in the gamma band.
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
28
Q

The subclasses of IgG differ mainly in

a. the type of L chain
b. the arrangement of disulfide bonds
c. the ability to act as opsonins
d. molecular weight

A

b. the arrangement of disulfide bonds

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
29
Q

Which best describes the role of the secretory component for IgA?

a. A transport mechanism across endothelial cells
b. A means of joining two IgA monomers together
c. An aid to trapping antigens
d. Enhancement of complement fixation by the classical pathway

A

a. A transport mechanism across endothelial cells

The secretory component (SC) plays a crucial role in the transport of IgA antibodies across endothelial cells, facilitating their secretion into mucosal surfaces, such as:
1. Respiratory tract
2. Gastrointestinal tract
3. Genitourinary tract

The SC:
1. Binds to IgA molecules
2. Forms secretory IgA (sIgA)
3. Transports sIgA across endothelial cells via transcytosis
4. Protects IgA from proteolytic degradation

This ensures IgA antibodies reach mucosal surfaces, providing immune protection against pathogens.

b. J-chain, not SC, joins IgA monomers.
c. IgA’s trapping antigens is a function of its antibody activity, not SC.
d. SC doesn’t enhance complement fixation; IgA activates the alternative complement pathway.

Note: IgA’s primary function is mucosal immunity, not complement activation.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
30
Q

Which represents the main function of IgD?

a. Protection of the mucous membranes
b. Removal of antigens by complement fixation
c. Enhancing proliferation of B cells
d. Destruction of parasitic worms

A

c. Enhancing proliferation of B cells
IgD’s main function:
1. Expressed on mature B cells’ surface
2. Acts as a receptor for antigen recognition
3. Activates B cells upon antigen binding
4. Enhances B cell proliferation and differentiation

IgD:
1. Plays a key role in the initiation of immune responses
2. Involved in antigen presentation and processing
3. Collaborates with IgM in early immune responses

The other options are incorrect:

a. IgA protects mucous membranes.
b. IgG and IgM are primarily involved in complement fixation.
d. IgE, not IgD, is associated with parasitic worm destruction.

Note: IgD’s exact function is still debated, but its role in B cell activation and proliferation is well-established.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
31
Q

Which antibody is best at agglutination and complement fixation?

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

A

d. IgM

IgM:
1. Most effective at agglutination (clumping of particles/organisms)
2. Strongest activator of the classical complement pathway
3. Provides immediate protection against infections

Characteristics:
1. Large pentameric structure (5 Ig units)
2. High avidity (binding strength)
3. Efficient at neutralizing pathogens

32
Q

Which of the following can be attributed to the clonal hypothesis of antibody formation?

a. Plasma cells make generalized antibody
b. B cells are preprogrammed for specific antibody synthesis
c. Proteins can alter their shape to conform to antigen
d. Cell receptors break off and become circulating antibody

A

b. B cells are preprogrammed for specific antibody synthesis

The Clonal Selection Hypothesis (1957) by Sir Frank Macfarlane Burnet states:

  1. Each B cell is genetically pre-programmed to produce a unique antibody specificity.
  2. Antigen binding selects and activates specific B cells.
  3. Activated B cells proliferate and differentiate into plasma cells.
  4. Plasma cells produce large amounts of their specific antibody.

Key points:
- B cells are pre-committed to produce specific antibodies.
- Antigen exposure selects and expands specific B cell clones.
- Clonal expansion ensures specific immune responses.

a. Plasma cells produce specific antibodies, not generalized.
c. Proteins can change shape, but this isn’t directly related to clonal hypothesis.
d. Cell receptors don’t break off to become circulating antibodies; B cells differentiate into plasma cells to produce antibodies.

This fundamental concept in immunology explains how our immune system generates specific responses to diverse antigens.

33
Q

All of the following are true of IgE except that it

a. fails to fix complement
b. is heat stable
c. attaches to tissue mast cells
d. is found in the serum of allergic persons

A

b. is heat stable

IgE characteristics:
1. Fails to fix complement (correct)
2. Heat-labile (not stable), unlike other immunoglobulins
3. Attaches to tissue mast cells and basophils (correct)
4. Found in the serum of allergic persons (correct)

IgE’s heat lability means it:
1. Denatures easily at high temperatures
2. Loses activity when exposed to heat

IgE’s roles:
1. Mediates allergic reactions (Type I hypersensitivity)
2. Involved in parasitic infections and immune responses

Other immunoglobulins (IgG, IgM, IgA, IgD) are generally heat stable.

Note: IgE’s heat lability is an important distinction as it affects laboratory handling and storage procedures.

34
Q

Which best describes coding for immunoglobulin molecules?

a. All genes located on the same chromosome
b. L chain rearrangement occurs before H chain rearrangement
c. Four different regions are involved in coding of H chains
d. Lambda rearrangement occurs before kappa rearrangement

A

c. Four different regions are involved in coding of H chains

Immunoglobulin (Ig) molecule coding involves:
1. Variable (V) region: encodes antigen-binding site
2. Diversity (D) region: adds diversity to V region
3. Joining (J) region: joins V and D regions
4. Constant (C) region: determines Ig class (e.g., IgG, IgM)

These four regions encode the Heavy (H) chain. Light (L) chains have only V, J, and C regions.

Key points:
- H chain rearrangement occurs after L chain rearrangement (not option b)
- Ig genes are located on different chromosomes (not option a):
- Heavy chain genes: chromosome 14
- Kappa (κ) light chain genes: chromosome 2
- Lambda (λ) light chain genes: chromosome 22
- Kappa (κ) rearrangement usually occurs before lambda (λ) rearrangement (opposite of option d)

Immunoglobulin gene rearrangement and expression:
1. V(D)J recombination: generates unique antigen receptors
2. Somatic hypermutation: introduces mutations for affinity maturation
3. Class switch recombination: changes Ig class (e.g., IgM to IgG)

Understanding Ig molecule coding is crucial for appreciating immune diversity and function.

35
Q

What is the purpose of HAT medium in the preparation of monoclonal antibody?

a. Fusion of the two cell types
b. Restricting the growth of myeloma cells
c. Restricting the growth of spleen cells
d. Restricting antibody production of the IgM class

A

b. Restricting the growth of myeloma cells

HAT (Hypoxanthine-Aminopterin-Thymidine) medium is used in monoclonal antibody production to:
1. Select for hybridoma cells (fusions of B cells and myeloma cells)
2. Inhibit the growth of unfused myeloma cells

HAT medium contains:
1. Aminopterin: blocks nucleotide synthesis
2. Hypoxanthine and thymidine: provide alternative pathways for nucleotide synthesis

Only hybridoma cells, having functional hypoxanthine-guanine phosphoribosyltransferase (HGPRT) enzyme from B cells, can survive in HAT medium.

HAT medium does not:
c. Restrict spleen cell growth (they die off naturally)
d. Restrict antibody production of the IgM class (HAT medium doesn’t affect antibody class)

Monoclonal antibody production steps:
1. Immunization and spleen cell isolation
2. Cell fusion with myeloma cells
3. HAT medium selection
4. Hybridoma screening and cloning
5. Antibody production and purification

HAT medium is crucial for selecting and expanding specific hybridoma cells, producing desired monoclonal antibodies.

36
Q

Papain digestion of an IgG molecule results in which of the following?

a. 2 Fab’ and 1 Fc’ fragment
b. F(ab’)2 and 1 Fc’ fragment
c. 2 Fab and 2 Fc fragments
d. 2 Fab and 1 Fc fragment

A

d. 2 Fab and 1 Fc fragment

Papain digestion of IgG:
1. Cleaves IgG at the hinge region
2. Produces:
- 2 Fab (Fragment Antigen-binding) fragments
- 1 Fc (Fragment crystallizable) fragment

Fab fragments:
- Retain antigen-binding activity
- Consist of VL, VH, CL, and CH1 domains

Fc fragment:
- Responsible for effector functions (e.g., complement activation)
- Consists of CH2 and CH3 domains

Papain digestion characteristics:
- Occurs at the hinge region’s susceptible sites
- Yields monovalent Fab fragments (bind single antigen epitope)

Other proteases:
- Pepsin: produces F(ab’)2 and pFc’ fragments
- Trypsin: produces Fab’ and Fc’ fragments (similar to papain)

37
Q

Which antibody provides protection to the growing fetus because it is able to cross the placenta?

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

A

a. IgG

38
Q

Which best characterizes the secondary response?

a. Equal amounts of IgM and IgG are produced
b. There is an increase in IgM only
c. There is a large increase in IgG but not IgM
d. The lag phase is the same as in the primary response

A

c. There is a large increase in IgG but not IgM

Secondary immune response characteristics:
1. Faster response (reduced lag phase)
2. Increased affinity and specificity
3. Dominance of IgG production (not equal IgM and IgG)
4. Memory B cells and plasma cells are involved

Key differences from primary response:
1. IgG predominates over IgM
2. Higher antibody titers and longer persistence
3. Improved antibody affinity and specificity
4. Memory cells facilitate rapid response

Primary vs. Secondary Response:

Primary:
- Initial exposure to antigen
- Slow response (lag phase)
- IgM dominates initially, then IgG

Secondary:
- Subsequent antigen exposure
- Rapid response (reduced lag phase)
- IgG dominates from the start

This distinction is crucial for understanding:
1. Immune memory and vaccination
2. Antibody-mediated immunity
3. Immunological recall responses

Note: The secondary response is more efficient and effective due to immune memory cells, leading to better protection against infections.

39
Q

Which immunoglobulin has the highest concentration?

A

IgG (70-75%)

40
Q

IgG half-life in serum (days)

A

23 (21-25)

41
Q

IgM half-life in serum (days)

A

6

42
Q

IgA half-life in serum (days)

A

5

43
Q

IgD half-life in serum (days)

A

1-3

44
Q

IgE half-life in serum (days)

A

2-3

45
Q

IgA in serum:
IgA in secretions:

A

IgA in serum: Monomer
IgA in secretions: Dimer

46
Q

Sedimentation coefficient of IgG:

A

7s

47
Q

Sedimentation coefficient of IgM:

A

19s

48
Q

Sedimentation coefficient of IgA:

A

7s

49
Q

Sedimentation coefficient of IgD:

A

7s

50
Q

Sedimentation coefficient of IgE:

A

8s

51
Q

Antibody produced in early immune response; opsonization; endotoxin neutralization; most primitive; also known as macroglobulin

A

IgM

52
Q

IgM antibody most often formed in response to __________ bacteria:

A

Gram-negative (-) bacteria

53
Q

What type of bond connects the H-H chain of a monomeric IgM?

A

Disulfide bond (S-S)

54
Q

Major immunoglobulin in normal serum that can cross the placenta (passive immunity of newborn)

A

IgG

55
Q

IgG subclass that is the most efficient in crossing the placenta:

A

IgG1

56
Q

IgG subclass that does not cross the placenta:

A

IgG2

57
Q

IgG subclass that is most efficient in complement fixation:

A

IgG3

58
Q

IgG subclass that does not fix complement:

A

IgG4

59
Q

Immunoglobulin that responds to carbohydrates antigens:

A

IgM

60
Q

Immunoglobulin that responds to protein antigens:

A

IgG

61
Q

How many disulfide bonds does IgG1 have?

A

2

62
Q

How many disulfide bonds does IgG2 have?

A

4

63
Q

How many disulfide bonds does IgG3 have?

A

15

64
Q

How many disulfide bonds does IgG4 have?

A

2

65
Q

Predominant immunoglobulin in secretions; present as dimer in secrations

A

IgA

66
Q

A cell membrane immunoglobulin found on the surface of B lymphocytes in association with IgM; serves as immunoregulation; helps in the differentiation and maturation of B cell into plasma cell

A

IgD

67
Q

Mediates some types of hypersensitivity reactions, allergies and anaphylaxis; is responsible for immunity to invading parasite; binds strongly to a receptor on mast cells and basophils with antigen, mediates the release of histamines and heparin from these cells

A

IgE

68
Q

IgE was originally called ______.

A

REAGIN

69
Q

Monoclonal antibodies was discovered by:

A

George Kohler and Cesar Milstein in 1975

70
Q

True or False

The myeloma cell line that is chosen is capable of producing antibody and is also deficient of the enzyme HGPRT (hypoxanthine guanine phosphoribosyl transferase) and thymidine kinase which are needed for DNA synthesis:

A

False

The myeloma cell line that is chosen is INCAPABLE OF PRODUCING AN antibody and is also deficient of the enzyme HGPRT (hypoxanthine guanine phosphoribosyl transferase) and thymidine kinase which are needed for DNA synthesis

71
Q

In hybridoma production, spleen cells are combined with myeloma cells in the presence of ____________ that fuses the cells, producing a hybridoma.

A

polyethylene glycol (PEG)

72
Q

In hybridoma production, fused myeloma cells die because the pathway that makes DNA from new nucleotides is inhibited by ____________:

A

aminopterin

72
Q

In hybridoma production, after fusion, cells are placed in culture using a selective medium containing _____________:

A

hypoxanthine, aminopterin, and thymidine (HAT)

73
Q

Clinical applications of monoclonal antibodies

In vitro diagnostics:

A
  1. Pregnancy testing (B-HCG)
  2. Detection of tumor antigens
  3. Measurement of hormones
74
Q

Clinical applications of monoclonal antibodies

Therapeutic agents:

A
  • Treatment for Rheumatoid arthritis and Crohn’s antigens
  • Metastatic breast CA
  • Non-Hodgkin’s Lymphoma
  • Colorectal, head and neck CA
  • Colorectal, non-small lung and breast cancers
  • For treatment of SARS-CoV2 (in some cases)
  • SARS-CoV2 neutralizing abs

IMMUNOLOGY & SEROLOGY (TopnotcherQT) (25 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2024 Bold Learning Solutions. Terms and Conditions