BACKGROUND Flashcards
1
Q
WHO HAS J CHAIN
A
IgM
2
Q
Valence of IgM
A
10
3
Q
Serum half life of IgM
A
5 days
4
Q
Does IgM cross the placenta
A
NO
5
Q
activation of classical pathway of complement of IgM
A
Yes very efficient than IgG
6
Q
Clearance of red cells of IgM
A
INTRAVASCULAR
7
Q
Chemicals used to destroy
J-chain of pentameric IgM:
A
Beta-2-mercaptoethanol
(2-ME)
Dithiothreitol (DTT)
8
Q
IgA also has J-chain if
_________
A
dimeric or trimeric
9
Q
Nuisance antibody
A
IgM
10
Q
_____ cannot bind antibodies in the
blood vessels (only in tissue,
extravascular)
A
IgG
11
Q
Predominant Ab produced in
the secondary response
A
IgG
12
Q
Blood groupsof IgG
A
Rh, Duffy, Kidd,
Kell
13
Q
Most concentrated in serum (80%)
A
IgG
14
Q
Reacts at body temperature.
Capable of destroying
transfused antigen-positive
RBCs.
A
IgG
15
Q
When exposed again in the
secondary period = __________
inductive period (memory
T-cells were formed, which
knows what antibody will be
produced).
A
SHORTER IN SECONDARY
16
Q
is the highest antibody
production = high memory
cells.
E.g., Vaccination
A
Secondary antibody
17
Q
Most commonly encountered
naturally occurring Ab (ABO
system
A
IgM
18
Q
Blood groups of IgM:
A
ABO, Lewis, Ii, P,
and MNS
19
Q
React best at ambient
temperature
Cold loving
A
IgM
20
Q
6% in serum
A
IgM
21
Q
Produced in response to
commonly occurring antigens:
○ Intestinal flora and pollen
grains
A
IgM
22
Q
Can interfere with detecting IgG
by masking their reactivity.
Can exist in monomeric or
pentameric form with J chain
A
IgM
23
Q
If IgM is secreted it is in
A
PENTAMERIC
24
Q
Exist as monomer, dimer
or trimer joined by J chain.
A
IgA
25
30% of anti-A and anti-B
are IgA Abs
TRUE
26
13% in the serum
IgA
27
Major Ab found in body
secretions
○ ** We can blood
type using saliva
IgA
28
Normally found in
monomeric form in trace
amounts
Least common Ab in the
serum; less than 1%
(0/004%)
IgE
29
Least significant in blood
banking.
1% in the serum
Has a short half-life of 1-3
days/
IgD
30
May cause severe
anaphylaxis if transfused
in IgA-deficient patients.
○ If a person is IgA
deficient and they
had been transfused
with blood that has
IgA, they would
produce anti-IgA.
○ The blood to be
transfused should
not contain IgA
IgA
31
Can increase the effect of
IgG-induced RBC
hemolysis.
IgA
32
May cause urticaria if
transfused in patients with
severe allergic reactions.
○ Due to release of
histamines
IgE
33
Not able to cross the
placenta and activate
complement.
IgD
34
Antibodies derived from more than one
antibody-producing parent cell.
Produced in response to a single antigen with more than
one epitope.
More sensitive than monoclonal.
POLYCLONAL
35
Antibodies derived from a single ancestral
antibody-producing parent cell.
Preferred in testing: highly specific, well characterized,
and uniformly reactive.
Preferred antisera in the laboratory because it's more
specific.
MONOCLONAL
36
Also called isoagglutinins; are significant in blood typing.
Found in individuals without previous exposure to RBC
Ags from transfusion, injection or pregnancy.
Naturally occurring antibodies
WITHOUT PREVIOUS
37
Found in individuals with previous exposure to
transfusion, injection and pregnancy.
Immune antibodies
IgG
38
Requires AHG (Coomb’s) sera for detection.
■ Either direct or indirect.
Immune antibodies
39
IN VIVO
DAT
40
IN VITRO
IAT
41
Produced after exposure to non-self antigens.
ALLOANTIBODIES
NON SELF
42
Produced in response to self-antigens.
○ Usually because of an autoimmune disease.
Transfused px with undetectable alloAb may elicit
stronger immune response against previous Ags and
cause severe transfusion rxns.
Positive autocontrol or direct antiglobulin test (DAT
AUTOANTIBODIES
DAT
43
Attraction between two molecules
on the basis of opposite charge; a positively charged region of a
molecule is attracted to the
negatively charged region of
another molecule.
Ionic bodning
44
Antibody is usually positively
charged, while the RBC is
negatively charged they are joined by what
IONIC BONDING
45
Attraction of two negatively charged
groups (X-) for a H+ atom
Hydrogen bonding
46
Result from weak dipole forces
between hydrogen atoms bonded to
oxygen or nitrogen atoms.
Hydrogen bonding
47
Weak bonds formed as a result of
the exclusion of water from the
antigen-antibody complex.
Albumin extracts the water from the surface of the RBC, which makes it easier to agglutinate.
Hydrophobic bonding
48
Attraction between the electron
cloud (-) of one atom and the
protons (+) within the nucleus of
another atom
Van der waals
49
_________ of RBC (the layer that gives the
negative charge) is destroyed,
then there would be less
attraction for the antibody.
○ Enzymes destroy sialic acid
so that red cells won't repel
each other.
SIALIC ACID
50
Strength of the binding between a single antibody and an epitope of an antigen.
1 antigen: 1 antibody
AFFINITY
SINGLE
51
Overall strength of reaction between
several epitopes and antibodies;
depends on the affinity of the antibody,
valency, and non covalent attractive
forces.
AVIDITY
several
52
Is a measure of functional affinity of an
antiserum for the whole antigen
Avidity
53
Multiple antibodies to a single antigen.
Avidity
54
Number of epitopes per molecule of
antigen
Valency
55
Number of antigen-binding sites on an
antibody molecule or number of
antibody-binding sites on an antigen.
Valency
56
similar epitopes
Specific reaction
57
certain epitopes are
shared by another antigen
Cross reaction
58
no shared epitopes
No reaction
59
Defined as the lack of an immune
response or an active
immunosuppressive response.
Preventing D-negative mothers from developing anti-D antibodies after
delivering Rh-positive infants.
TOLERANCE
60
exposure to an
antigen during fetal life;
organisms derived from different
species.
Chimera
61
Host Factors: Properties of the Host That
Influence Immune Response
1. Nutritional status
2. Hormones
3. Genetics
4. Age
5. Race
6. Exercise level
7. Disease
8. Injury
62
severe protein deficiency; this
would severely affect the
antibody because it is made up of nutritional status.
Kwashiorkor and marasmus
63
Reverse blood typing can’t be
used in babies.
TRUE
64
has naturally occurring antibodies
ABO
65
has strongly immunogenic D antigen
Rh
66
only applicable to ABO and Rh type
Blood typing
67
Factors influencing antigen-antibody reactions include:
1. Intermolecular binding forces
2. Antibody properties
3. Host factors
4. Tolerance
68
Antigen-antibody reaction
Triggered by IgM or IgG and antigen
Has to have antigen antibody complex
Classical pathway
69
Only takes 1 IgM to activate
■ Due to pentameric structure
■ Due to more Fabs = higher valency (10)
■ Bigger and more complex = better efficacy
Classical pathway
70
Takes several IgG to activate (multiple, usually
6)
Classical pathway
71
Major outcome: _______
Has 9 proteins that will cascade
Once activated, it will cause _____
LYSIS
CLASSICAL PATHWAY
72
Membrane property of a
microorganism
To increase classical and MB
Lectin pathway [always on but in
the background only]
Alternative as it shortens the
pathway
Alternative pathway
73
Present in surface of most
pathogens
Mannose binding lectin pathway
74
In vitro RBC Ag-Ab reactions are detected by visible agglutination (hemagglutination) or
hemolysis
TRUE
IAT
75
indicator of antigen-antibody reaction in
Agglutination
76
Attachment of Ab to corresponding Ag on RBC membrane
Sensitization
77
Not visible in naked eye
Sensitized
78
Combination of antibody and a multivalent antigen to form crosslinks.
LATTICE
79
Visible to the naked eye
Lattice
80
Factors that influence agglutination reactions:
Factors that influence agglutination reactions:
A. Centrifugation
B. Ag-Ab Ratio
C. pH
D. Temperature
E. Ig Type
F. Enhancement Media
G. Ionic Strength
81
Some antibodies are very poor in causing agglutination and stops at
sensitization phase
False negative
82
easier to agglutinate
IgM
83
sensitization only ⟶ does not
proceed to lattice formation ⟶ add
IgG ; AHG (Antihuman Globulin)
84
In IgG, there is _____
distance from RBCs
14 nm
85
In IgM, there is ____
distance from RBCs
35 nm
86
■ Attaches the 2 RBCs = lattice formation
■ Acts as a bridge molecule between RBCs
AHG (anti-human globulin)
87
Enhances
agglutination reactions
Decreases reaction
time by increasing the
gravitational forces on
the reactants to
bringing reactants
closer together
Allows RBCs to
compact
A. CENTRIFUGATION
88
excess (Post-Ag)
Postzone reaction
89
excess (Pro-Ab)
Prozone reaction
90
ideal reactive conditions
necessary for
agglutination reactions to
occur
Zone of equivalence
91
ratio
(most preferred)
1:1 or 2:1
92
(antisera:red cell
suspension)
Forward- 1:1
93
(serum:known
cells)
Reverse- 2:1
94
Difference in negative
charge between the inner
and outer surfaces of the
cloud
RBCs are surrounded by
negative ions when they are
suspended in isotonic saline
ZETA POTENTIAL
DISTANCE
95
Higher zeta potential =
more difficult to
agglutinate cells
TRUE
96
Faster agglutination =
decrease zeta
potential by using _____
PROTEIN MEDIA
97
Decreases ZP by increasing
dielectric constant or adding
more cations
Albumin, PEG, polybrene,
polyvinylpyrrolidone (PVP),
protamine
PROTEIN MEDIA
98
Colloidal substances
utilized to enhance
agglutination reactions
Protein media
99
Low salt media: ________
0.2% NaCl
100
Decreases uptake of
antibody
Increases binding of
antibody to antigen
Used in STAT requests
Also known as the _____
LOW IONIC STRENGTH SOLUTION (LISS)
RAPID ANTIBIDY MEDIYM
101
Decrease the ionic strength
of a reaction medium,
reduces the ZP and allows
Abs to react more efficiently
with RBC membrane Ags
May result in false-positive
reactions and require testing
to be repeated with albumin
Low Ionic strength solution
102
Cleaves sialic acid from RBC
membrane → negative
charges and ZP
Proteolytic enzymes
103
isolated from fig
plants
FICIN
104
papaya
Papain
105
pig stomach
Trypsin
106
pineapple
Bromelin
107
human /
porcine stomach
Pepsin
108
human /
porcine stomach
Pepsin
109
Enhancedby proteolytic enzymes:
Rh, Kidd, P1,
Lewis, and I Ags
110
Depressed by proteolytic enzymes
MNSs, Duffy, ags
111
Determine if RBCs are
coated with Ab and/or
complement
○ Small IgG antibodies
can sensitize but rarely
cause agglutination.
○ Cannot overcome zeta
potential
AHG
112
digests area
below hinge region
= producing 2
fragments (Fab2,
pepsin)
Pepsin
113
digests
above hinge region
= producing 3
fragments (2 Fab,
Fc)
Papain
114
Distance between cells caused by charged
ions
Zeta potential
115
pH
7.0
