Review Cards - Immunology Flashcards
(548 cards)
1
Q
Proteins that increase due to infection, injury, trauma (e.g., C-reactive protein, alpha-1 antitrypsin, haptoglobin, fibrinogen, ceruloplasmin, alpha-1 acid glycoprotein, complement)
A
Acute phase reactants
2
Q
Antibody formed in response to antigen from individuals of same species
A
Alloantibody
3
Q
Foreign substance that can stimulate antibody production; most often a large, complex molecule (MW = >10,000), usually protein or polysaccharide
A
Antigen
4
Q
Immunoglobulin produced by plasma cells in response to an antigen
A
Antibody
5
Q
Antibody against self
A
Autoantibody
6
Q
Strength of bond between antigen & antibody
A
Avidity
7
Q
Cytokines that attract cells to a particular site; important in the inflammatory response
A
Chemokines
8
Q
Migration of cells toward chemokine
A
Chemotaxis
9
Q
Antigenic features of leukocytes
A
Clusters of differentiation (CD)
10
Q
Chemicals produced by activated immune cells that affect function of other cells; includes interferons, chemokines, tumor necrosis factors, transforming growth factors, colony stimulating factors, interleukins
A
Cytokines
11
Q
Determinant site on antigen
A
Epitope
12
Q
Low molecular weight substance that can bind to antibody once it’s formed, but is incapable of stimulating antibody production unless bound to a larger carrier molecule
A
Hapten
13
Q
Heightened state of immune responsiveness that can cause tissue damage in host
A
Hypersensitivity
14
Q
Resistance to infection
A
Immunity
15
Q
Any substance capable of inducing an immune response
A
Immunogen
16
Q
Antibody
A
Immunoglobulin
17
Q
Cellular & humoral mechanisms involved in reaction to injury or infection
A
Inflammation
18
Q
Cytokines with antiviral properties; also active against certain tumors & inflammatory processes
A
Interferons
19
Q
Cytokines produced by leukocytes that affect inflammatory response through increase in soluble factors or cells
A
Interleukins
20
Q
Molecule that binds to another molecule of complementary configuration; the substance being measured in an immunoassay
A
Ligand
21
Q
Enzyme found in tears & saliva that attacks cell walls of microorganisms
A
Lysozyme
22
Q
System of genes that control expression of MHC molecules found on all nucleated cells; originally referred to as human leukocyte antigens (HLA)
A
Major histocompatibility complex (MHC)
23
Q
Antibody derived from single B-cell clone, frequently used in clinical laboratory assays such as enzyme-linked immunosorbent assay (ELISA)
A
Monoclonal antibody
24
Q
Serum proteins that attach to a foreign substance & enhance phagocytosis; most often complement or antibody
A
Opsonin
25
Step-wise engulfment of cells or particulate matter by neutrophils & macrophages
Phagocytosis
26
Transformed B cells that secret antibody
Plasma cells
27
Antibody produced by many B-cell clones
Polyclonal antibody
28
Reduced ag/ab complexes due to antigen excess; can cause false negative in serological test for antibodies; repeat test in 1-2 weeks
Postzone
29
Reduced ag/ab complexes due to antibody excess; can cause false negative in serological tests for antibodies; dilute serum & retest
Prozone
30
Change of serological test from negative to positive due to development of detectable antibodies
Seroconversion
31
Small, flat bilobed organ found in thorax; site of T-lymphocyte development; one of two primary lymphoid organs (bone marrow is the other primary lymphoid organ)
Thymus
32
Means of expressing antibody concentration; reciprocal of highest dilution with positive reaction
Titer
33
Injection of immunogenic material to induce immunity
Vaccination
34
When the number of multivalent sites of antigen & antibody are approximately equal; results in optimal reactions
Zone of equivalence
35
Branches of the immune system - Cellular - definition
cell-mediated
36
Branches of the immune system - Cellular - defense against
-viruses
-fungi
-mycobacteria
-other intracellular pathogens
-tumor cells
37
Branches of the immune system - Cellular - cells involved
-T-cells
-macrophages
38
Branches of the immune system - Cellular - examples
-graft rejection
-hypersensitivity reactions
-elimination of tumor cells
39
Branches of the immune system - Humoral - definition
antibody mediated
40
Branches of the immune system - Humoral - defense against
bacteria (extracellular)
41
Branches of the immune system - Humoral - cells involved
-B cells
-plasma cells
42
Branches of the immune system - Humoral - examples
antibody production
43
Types of immunity - innate - explanation
defense mechanisms present at birth; not antigen specific
44
Types of immunity - innate - components
External defense system:
-intact skin
-mucous membranes
-cilia & mucus in RT
-stomach acid
-flushing of urine
-lactic acid in vagina
-lysozyme in tears & saliva
-normal flora
Internal defense system:
-neutrophils
-macrophages
-acute phase reactants
-complement
-chemokines
45
Types of immunity - innate - memory?
NO
46
Types of immunity - acquired or adaptive - explanation
defense mechanisms that are antigen specific
47
Types of immunity - acquired or adaptive - components
-T-cells
-B-cells
-plasma cells
-antibodies
-cytokines
48
Types of immunity - acquired or adaptive - memory?
YES
49
Adaptive immunity - naturally acquired active immunity - explanation
individual infected with microorganism produces antibodies
50
Adaptive immunity - naturally acquired active immunity - example
clinical or subclinical infection
51
Adaptive immunity - naturally acquired active immunity - specific?
yes
52
Adaptive immunity - naturally acquired active immunity - immediate?
no
53
Adaptive immunity - naturally acquired active immunity - long-term?
yes
54
Adaptive immunity - artificially acquired active immunity - explanation
individual exposed to antigen through vaccine develops immunity without having the infection
55
Adaptive immunity - artificially acquired active immunity - explanation
individual exposed to antigen through vaccine develops immunity without having the infection
56
Adaptive immunity - artificially acquired active immunity - example
-Diphtheria, tetanus, pertussis vaccine (DTap)
-measles, mumps, rubella vaccine (MMR)
-polio vaccine
-tetanus vaccine
-*Haemophilus influenzae* type b (Hib) vaccine
57
Adaptive immunity - artificially acquired active immunity - specific?
yes
58
Adaptive immunity - artificially acquired active immunity - immediate?
no
59
Adaptive immunity - artificially acquired active immunity - long-term?
yes
60
Adaptive immunity - naturally acquired passive immunity - explanation
individual protected by antibodies produced by another person
61
Adaptive immunity - naturally acquired passive immunity - example
maternal antibodies that cross the placenta and are present in breast milk
62
Adaptive immunity - naturally acquired passive immunity - specific?
yes
63
Adaptive immunity - naturally acquired passive immunity - immediate?
yes
64
Adaptive immunity - naturally acquired passive immunity - long-term?
no
65
Adaptive immunity - artificially acquired passive immunity - explanation
individual receives immune globulin containing antibodies produced by another person
66
Adaptive immunity - artificially acquired passive immunity - example
-Rh immune globulin
-convalescent plasma
-antitoxins
67
Adaptive immunity - artificially acquired passive immunity - specific?
yes
68
Adaptive immunity - artificially acquired passive immunity - immediate?
yes
69
Adaptive immunity - artificially acquired passive immunity - long-term?
no
70
Cells of the innate immune system - granulocytes - neutrophils - function
-phagocytosis
-inflammatory response
71
Cells of the innate immune system - granulocytes - neutrophils - respond to?
Chemotaxins
72
Cells of the innate immune system - granulocytes - neutrophils - granules contain?
Bactericidal enzymes
73
Cells of the innate immune system - granulocytes - eosinophils - function
-neutralization of basophil & mast cell products
-destruction of some helminths
-hypersensitivity reactions
74
Cells of the innate immune system - granulocytes - eosinophils - phagocytic ability?
Some
75
Cells of the innate immune system - granulocytes - basophils - function
Hypersensitivity reactions
76
Cells of the innate immune system - granulocytes - basophils - granules contain?
Histamine, heparin, eosinophil chemotactic factor A
77
Cells of the innate immune system - granulocytes - basophils - bind to what in an allergic reaction?
IgE
78
Cells of the innate immune system - granulocytes - basophils - when do granules release contents?
In presence of antigen
79
Cells of the innate immune system - mononuclears - monocytes - function
Phagocytosis
80
Cells of the innate immune system - Tissue cells - mast cells - function
Hypersensitivity reactions
81
Cells of the innate immune system - Tissue cells - mast cells - what type of cells?
Connective tissue cells
82
Cells of the innate immune system - Tissue cells - mast cells - similar to basophils
Yes, but they are larger and have more granules
83
Cells of the innate immune system - Tissue cells - mast cells - what do they bind to?
IgE
84
Cells of the innate immune system - mononuclears - monocytes - migration
Migrate to the tissues and become macrophages
85
Cells of the innate immune system - Tissue cells - mast cells - respond to?
Chemotaxins
86
Cells of the innate immune system - Tissue cells - macrophages - function
-phagocytosis
-elimination of bacteria, intracellular parasites, & tumor cells
-secretion of cell mediators
-antigen presentation
87
Cells of the innate immune system - Tissue cells - macrophages - activated by?
Contact with microorganisms or cytokines from T cells
88
Cells of the innate immune system - Tissue cells - dendritic cells - function
-phagocytosis
-presentation of antigens to T cells
89
Cells of the innate immune system - Tissue cells - dendritic cells - initiate?
Adaptive immune response
90
Cells of the innate immune system - Lymphocytes - Natural Killer (NK) cells - function
1st line of defense against tumor cells & cells infected with viruses
91
Cells of the innate immune system - Lymphocytes - Natural Killer (NK) cells - lymphocytes without?
T or B markers
92
Cells of the innate immune system - Lymphocytes - Natural Killer (NK) cells - surface antigens?
no unique surface antigens, but CD16+ and CD56+
93
Cells of the innate immune system - Lymphocytes - Natural Killer (NK) cells - bridge between?
innate and acquired immunity
94
Cells of the innate immune system - Lymphocytes - Natural Killer (NK) cells - specificity?
no
95
Cells of the innate immune system - Lymphocytes - Natural Killer (NK) cells - stimulated by?
cytokines
96
Cells of the innate immune system - Lymphocytes - Natural Killer (NK) cells - released?
early infection - provides time for T & B cells to be activated
97
Cells of the innate immune system - Lymphocytes - Natural Killer (NK) cells - % of lymphs?
<20%
98
Cells of the innate immune system - Lymphocytes - Natural Killer (NK) cells - key cell in what?
antibody-dependent cellular cytotoxicity (ADCC)
99
Cells of the acquired immune system - T-lymphocytes (T cells) - function
cell-mediated immunity
100
Cells of the acquired immune system - T-lymphocytes (T cells) - derived from?
cells in bone marrow
101
Cells of the acquired immune system - T-lymphocytes (T cells) - where do they develop T-cell-specific surface antigens?
thymus
102
Cells of the acquired immune system - T-lymphocytes (T cells) - % of lymphs?
60-80%
103
Cells of the acquired immune system - Helper T cells - function
-orchestrate cell-mediated immunity
-activate B cells, cytotoxic cells, & NK cells
104
Cells of the acquired immune system - Helper T cells - surface antigen
CD4+
105
Cells of the acquired immune system - Helper T cells - constitutes how much of peripheral T cells?
2/3
106
Cells of the acquired immune system - Helper T cells - normal CD4 concentration
1,000/uL
107
Cells of the acquired immune system - Helper T cells - CD4 concentration in AIDS
<200/uL
108
Cells of the acquired immune system - Cytotoxic T cells - function
-suppressor cells inhibit helper T cells
-cytotoxic cells kill other cells
109
Cells of the acquired immune system - Cytotoxic T cells - surface antigen
CD8+
110
Cells of the acquired immune system - Cytotoxic T cells - constitutes how much of peripheral T cells?
1/3
111
Cells of the acquired immune system - Cytotoxic T cells - normal CD4/CD8 ratio?
2:1
112
Cells of the acquired immune system - Cytotoxic T cells - CD4/CD8 ratio in AIDS?
<0.5:1
113
Cells of the acquired immune system - T regulatory cells - function
suppress immune response to self
114
Cells of the acquired immune system - T regulatory cells - surface antigens
CD4+ and CD25+
115
Cells of the acquired immune system - B lymphocytes (B cells) - function
after antigenic challenge, transform into blasts that give rise to plasma cells & memory cells
116
Cells of the acquired immune system - B lymphocytes (B cells) - develop where?
bone marrow
117
Cells of the acquired immune system - B lymphocytes (B cells) - mature cells have what on their surface?
immunoglobulins (IgM, IgD) that act as receptors for antigens
118
Cells of the acquired immune system - B lymphocytes (B cells) - constitute what percentage of lymphs in peripheral blood?
10-20%
119
Cells of the acquired immune system - plasma cells - function
antibody production
120
Cells of the acquired immune system - plasma cells - where are they located?
in peripheral lymphoid organs
121
Cells of the acquired immune system - plasma cells - do they divide?
no
122
Cells of the acquired immune system - memory cells - function
respond to antigens when encountered again with increased speed & intensity
123
Cells of the acquired immune system - memory cells - located?
in peripheral organs
124
Cells of the acquired immune system - memory cells - live span?
months to years
125
Cells of the acquired immune system - memory cells - what type of cells?
can be B or T cells
126
List the primary lymphoid organs.
-bone marrow
-thymus
127
List the secondary lymphoid organs.
-spleen
-lymph nodes
-tonsils
-appendix
-cutaneous-associated lymphoid tissue
-mucosal-associated lymphoid tissue (MALT), including Peyer patches in the lower ileum
128
Isolation & identification of lymphocytes - isolation
-density gradient centrifugation with separation media (e.g., Ficoll-Hypaque)
-layers from top to bottom:
--plasma
--mononuclear cells
--separation media
--RBCs
--granulocytes
129
Isolation & identification of lymphocytes - identification
-flow cytometry
-fluorescent-labeled monoclonal antibodies against specific surface antigens
-each antibody has different fluorescent tag
-light scattering measured as cells flow through laser beam
-common T-cell antigens tested: CD2, CD3, CD4, CD7, CD8
-common B-cell antigens tested: CD19, CD20, CD22, surface Ig
130
Immunoglobulin (Ig) structure - basic structure
2 heavy (H) chains + 2 light (L) chains held together by disulfide (S-S) bonds
131
Immunoglobulin (Ig) structure - heavy (H) chains
-determine Ig class (IgG, IgA, IgM, IgD, IgE)
-gamma, alpha, delta, mu, epsilon
132
Immunoglobulin (Ig) structure - light (L) chains
-kappa or lambda
-both found in all classes of Igs, but only 1 type per molecule
-free L chains = Bence Jones proteins
133
Immunoglobulin (Ig) structure - Fab fragment
-fragment antigen binding
-consists of 1 L chain & 1/2 H chain held together by S-S bonds
-2 per Ig
-each can bind antigen
134
Immunoglobulin (Ig) structure - Fc fragment
-fragment crystallizable
-carboxy-terminal halves of 2 H chains held together by S-S bonds
-site of antibody biological activity such as opsonization & complement fixation
135
Immunoglobulin (Ig) structure - Constant region
carboxy-terminal ends of H & L chains where amino acid sequence is same for all chains of that type
136
Immunoglobulin (Ig) structure - variable region
-amino-terminal ends of H & L chains where amino acid sequence varies
-also known as antigen-recognition unit
-responsible for Ig specificity
137
Immunoglobulin (Ig) structure - Hinge region
-flexible portion of H chain between 1st & 2nd constant regions
-allows molecule to bend so that 2 antigen-binding sites can operate independently
138
Immunoglobulin (Ig) structure - Joining chain
glycoprotein that links Ig monomers in IgM & secretory IgA
139
Immunoglobulins - IgG - form in serum
monomer
140
Immunoglobulins - IgG - molecular weight (daltons)
150,000
141
Immunoglobulins - IgG - H chain
gamma
142
Immunoglobulins - IgG - L chain
Kappa or lambda
143
Immunoglobulins - IgG - % of total Ig
70-75%
144
Immunoglobulins - IgG - % of total Ig
70-75%
145
Immunoglobulins - IgG - serum concentration (mg/dL)
800-1,600 mg/dL
146
Immunoglobulins - IgG - antigen binding sites
2
147
Immunoglobulins - IgG - complement fixation
yes
148
Immunoglobulins - IgM - form in serum
pentamer
149
Immunoglobulins - IgM - molecular weight (daltons)
900,000
150
Immunoglobulins - IgM - H chain
Mu
151
Immunoglobulins - IgM - L chain
kappa or lambda
152
Immunoglobulins - IgM - % of total Ig
10%
153
Immunoglobulins - IgM - serum concentration (mg/dL)
120-150 mg/dL
154
Immunoglobulins - IgM - antigen binding sites
10
155
Immunoglobulins - IgM - complement fixation
yes
156
Immunoglobulins - IgA - form in serum
monomer & dimer
157
Immunoglobulins - IgA - molecular weight (daltons)
160,000 or 400,000
158
Immunoglobulins - IgA - H chain
alpha
159
Immunoglobulins - IgA - L chain
kappa or lambda
160
Immunoglobulins - IgA - % of total Ig
10-15%
161
Immunoglobulins - IgA - serum concentration (mg/dL)
70-350 mg/dL
162
Immunoglobulins - IgA - antigen binding sites
2 or 4
163
Immunoglobulins - IgA - antigen binding sites
2 or 4
164
Immunoglobulins - IgA - complement fixation
no
165
Immunoglobulins - IgD - form in serum
monomer
166
Immunoglobulins - IgD - molecular weight (daltons)
180,000
167
Immunoglobulins - IgD - H chain
delta
168
Immunoglobulins - IgD - L chain
kappa or lambda
169
Immunoglobulins - IgD - % of total Ig
<1%
170
Immunoglobulins - IgD - serum concentration (mg/dL)
1-3 mg/dL
171
Immunoglobulins - IgD - antigen binding sites
2
172
Immunoglobulins - IgD - complement fixation
no
173
Immunoglobulins - IgE - form in serum
monomer
174
Immunoglobulins - IgE - molecular weight (daltons)
190,000
175
Immunoglobulins - IgE - H chain
epsilon
176
Immunoglobulins - IgE - L chain
kappa or lambda
177
Immunoglobulins - IgE - % of total Ig
0.002%
178
Immunoglobulins - IgE - serum concentration (mg/dL)
0.005 mg/dL
179
Immunoglobulins - IgE - antigen binding sites
2
180
Immunoglobulins - IgE - complement fixation
no
181
Immunoglobulins - IgG - crosses placenta?
Yes
182
Immunoglobulins - IgG - role(s)
-defense against bacteria & viruses
-neutralizes toxins
-opsonin
-passive immunity in newborns
183
Immunoglobulins - IgG - precipitation/agglutination
more efficient at precipitation than agglutination
184
Which immunoglobulin is the main Ig produced during memory (recall) response to antigens?
IgG
185
Immunoglobulins - IgM - crosses placenta?
no
186
Immunoglobulins - IgM - role(s)
-neutralizes toxins
-opsonin
187
Immunoglobulins - IgM - more efficient at what than IgG?
agglutination
188
Immunoglobulins - IgM - destroyed by?
sulfhydryl compounds
189
Which immunoglobulin is the first Ig produced in the immune response?
IgM
190
Which immunoglobulin is the only Ig produced by newborns?
IgM
191
Which immunoglobulin is the only Ig produced by newborns?
IgM
192
Which immunoglobulin is the most efficient Ig at initiating the complement cascade?
IgM
193
Immunoglobulins - IgA - crosses placenta?
no
194
Immunoglobulins - IgA - role(s)
-1st line of defense
-patrols mucosal surfaces
-prevents adherence of bacteria and neutralizes toxins
195
Immunoglobulins - IgA - located?
-tears
-sweat
-respiratory mucosa
-GI mucosa
-breast milk
196
Immunoglobulins - IgD - crosses placenta?
no
197
Immunoglobulins - IgD - role(s)
may play a role in B-cell maturation
198
Immunoglobulins - IgD - on surface of what cells?
B cells
199
Immunoglobulins - IgE - crosses placenta?
no
200
Immunoglobulins - IgE - role(s)
-role in allergic reactions
-binds to basophils & mast cells
-when 2 adjacent molecules on mast cells bind antigens, degranulation of cell with release of histamine & heparin
201
Immunoglobulins - IgE - type of hypersensitivity reaction
Type I immediate hypersensitivity reaction
202
Complement - definition
-group of >30 proteins involved in phagocytosis & clearance of foreign antigen
-most are inactive enzyme precursors that are converted to active enzymes in precise order (cascade)
203
Complement - functions
-inflammation
-opsonization
-chemotaxis
-cell lysis
204
Complement - classical pathway
-triggered by ag/ab reaction
-IgM is most efficient activator
-single molecule attached to 2 adjacent antigens can initiate cascade
-IgG1, 2, & 3 can activate complement but at least 2 molecules required
-recognition unit: C1 (first to bind)
-activation unit: C4, C2, C3
-membrane attack complex: C5, C6, C7, C8, C9 (cell lysis)
205
Complement - alternative pathway
-antibody dependent
-activated by bacteria, fungi, viruses, tumor cells, some parasites
206
Complement - lectin pathway
-antibody independent
-initiated by mannose-binding lectin (MBL)
-nonspecific recognition of sugars on microorganisms
-important defense mechanism in infancy
207
Complement - present in highest concentration in plasma
C3 (key component of all 3 pathways)
208
Complement - deficiencies
-increased susceptibility to infection
-accumulation of immune complexes, which can lead to glomerulonephritis
209
Complement - ions required
calcium and magnesium
210
Complement - inactivation
56*C for 30 minutes
211
Hypersensitivity reactions - Type I: Anaphylactic - key reactant(s)
IgE
212
Hypersensitivity reactions - Type I: Anaphylactic - mechanism
release of mediators from eosinophils, mast cells, & basophils
213
Hypersensitivity reactions - Type I: Anaphylactic - onset of symptoms
immediate
214
Hypersensitivity reactions - anaphylaxis - type of hypersensitivity reaction?
Type I: Anaphylactic
215
Hypersensitivity reactions - hay fever - type of hypersensitivity reaction?
Type I: Anaphylactic
216
Hypersensitivity reactions - asthma - type of hypersensitivity reaction?
Type I: Anaphylactic
217
Hypersensitivity reactions - food allergies - type of hypersensitivity reaction?
Type I: Anaphylactic
218
Hypersensitivity reactions - transfusion reactions - type of hypersensitivity reaction?
Type II: Cytotoxic
219
Hypersensitivity reactions - HDN - type of hypersensitivity reaction?
Type II: Cytotoxic
220
Hypersensitivity reactions - autoimmune hemolytic anemia - type of hypersensitivity reaction?
Type II: Cytotoxic
221
Hypersensitivity reactions - Arthus reaction - type of hypersensitivity reaction?
Type III: Immune complex
222
Hypersensitivity reactions - serum sickness - type of hypersensitivity reaction?
Type III: Immune complex
223
Hypersensitivity reactions - SLE - type of hypersensitivity reaction?
Type III: Immune complex
224
Hypersensitivity reactions - rheumatoid arthritis (RA) - type of hypersensitivity reaction?
Type III: Immune complex
225
Hypersensitivity reactions - contact dermatitis - type of hypersensitivity reaction?
Type IV: Cell dependent
226
Hypersensitivity reactions - hypersensitivity pneumonitis - type of hypersensitivity reaction?
Type IV: Cell dependent
227
Hypersensitivity reactions - tuberculin skin test - type of hypersensitivity reaction?
Type IV: Cell dependent
228
Hypersensitivity reactions - Type II: Cytotoxic - key reactant(s)
IgG, IgM, complement, cellular antigens
229
Hypersensitivity reactions - Type II: Cytotoxic - mechanism
cytolysis due to antibody & complement
230
Hypersensitivity reactions - Type II: Cytotoxic - onset of symptoms
immediate
231
Hypersensitivity reactions - Type II: Immune Complex - key reactant(s)
IgG, IgM, complement, soluble antigen
232
Hypersensitivity reactions - Type III: Immune Complex - key reactant(s)
IgG, IgM, complement, soluble antigen
233
Hypersensitivity reactions - Type III: Immune Complex - mechanism
deposits of antigen-antibody complexes in tissues
234
Hypersensitivity reactions - Type III: Immune Complex - onset of symptoms
immediate
235
Hypersensitivity reactions - Type IV: T-Cell Dependent - key reactant(s)
T cells, antigen-presenting cells (APCs)
236
Hypersensitivity reactions - Type IV: T-Cell Dependent - mechanism
release of cytokines
237
Hypersensitivity reactions - Type IV: T-Cell Dependent - onset of symptoms
delayed - sensitization after 1st contact with antigen, symptoms upon reexposure
238
Agglutination methods - direct agglutination - principle
-naturally occurring antigens on particles (e.g., bacterial antigens)
-particles agglutinate in the presence of corresponding antibody
239
Agglutination methods - direct agglutination - application
-Widal test for typhoid fever
-Salmonella O & H antigens used to detect antibodies in patient serum
-test used in developing countries
240
Agglutination methods - hemagglutination - principle
antigen-antibody reactions that results in clumping of RBCs
241
Agglutination methods - hemagglutination - application
ABO typing
242
Agglutination methods - passive (indirect) agglutination - principle
-soluble antigens bound to particles, e.g., latex
-particles agglutinate in presence of corresponding antibody
243
Agglutination methods - passive (indirect) agglutination - application
antibody to Group A *Streptococcus* (GAS) or antibody to rotavirus or cytomegalovirus (CMV)
244
Agglutination methods - reverse passive agglutination - principle
-antibody attached to carrier particles
-particles agglutinate in presence of corresponding antigen
245
Agglutination methods - reverse passive agglutination - application
-kits available for rapid ID of bacteria such as Group B *Streptococcus* (GBS), *Staphylococcus aureus*, and *Cryptococcus neoformans*
246
Agglutination methods - agglutination inhibition - principle
-competition between particulate antigen (reagent) & soluble antigen (in specimen) for sites on reagent antibody
-lack of agglutination is a positive results
247
Agglutination methods - agglutination inhibition - application
-detection of illicit drugs
-controls are crucial to confirm lack of agglutination
248
Agglutination methods - hemagglutination inhibition - principle
-detects antibodies to certain viruses that agglutinate RBCs
-in presence of antibody, virus is neutralized & hemagglutination doesn't occur
249
Agglutination methods - hemagglutination inhibition - application
-Rubella & other viruses
-controls are crucial to confirm lack of hemagglutination
250
Precipitation methods - precipitation - principle
-soluble antigen combines with soluble antibody to produce visible complexes
-less sensitive than agglutination
251
Precipitation methods - Ouchterlony double diffusion - principle
antigens & antibodies diffuse from wells in gel & form precipitin lines where they meet
252
Precipitation methods - Ouchterlony double diffusion - application
fungal antigens
253
Precipitation methods - Radial immunodiffusion (RID) - principle
-antigen diffuses out of well in gel containing antibody
-precipitin ring forms
-diameter proportionate to concentration of antigen
254
Precipitation methods - Radial immunodiffusion (RID) - application
largely replaced by more sensitive methods such as nephelometry and enzyme-linked immunoassays
255
Precipitation methods - Immunofixation electrophoresis (IFE) - principle
-proteins separated by electrophoresis
-antiserum places directly in gel
-antigen-antibody complexes precipitate
256
Precipitation methods - Immunofixation electrophoresis (IFE) - application
-identification of Igs in monoclonal gammopathies
-Bence Jones proteins
-also useful for detection of antigen present in serum, urine, or CSF at low concentrations
257
Precipitation methods - Nephelometry - principle
-light scattering by antigen-antibody complexes
-amount of light scattered is proportional to concentration
258
Precipitation methods - Nephelometry - application
-Igs
-complement
-C-reactive protein (CRP)
-haptoglobin
-ceruloplasmin
259
substance being measured in immunoassay; can be antigen or antibody
ligand
260
immunoassay in which patient antigen & labeled reagent antigen compete for binding sites on reagent antibody
competitive
261
immunoassay that doesn't involve competition for binding sites; more sensitive than competitive assays
noncompetitive
262
immunoassay with separation step to remove from bound analyte; more sensitive than homogeneous assays
heterogeneous
263
immunoassay that doesn't require separation step; easier to automate
homogeneous
264
any immunoassay that uses an enzyme as a label; a substrate is added to measure enzyme activity
EIA
265
1st type of EIA developed; competitive; enzyme-labeled reagent is part of initial ag-ab reaction; all reactants added at same time; 1 incubation & 1 wash
Direct EIA
266
noncompetitive EIA; enzyme-labeled reagent isn't involved in initial ag-ab reaction; 2 incubations & 2 washes; more sensitive than direct assays; also known as ELISA
Indirect EIA
267
reagent ag or ab bound to support medium, e.g., polystyrene test tubes, microtiter plates, cellulose membranes, glass beads
solid phase
268
EIA formats - EIA - description
heterogeneous, competitive, direct
269
EIA formats - EIA - principle
-enzyme-labeled ligand & unlabeled patient ligand compete for binding sites on antibody attached to solid phase
-free labeled ligand removed by washing
-substrate added
-color inversely proportional to concentration of ligand in specimen
270
EIA formats - EIA - used to measure?
small relatively pure antigens, e.g., insulin, estrogen
271
EIA formats - ELISA - description
heterogeneous, noncompetitive, indirect
272
EIA formats - ELISA - principle
-antigen attached to solid phase
-antibody in specimen attaches
-unbound antibody removed by washing
-enzyme-labeled antiglobulin added
-attaches to antibody on solid phase
-substrate added
-color directly proportional to antibody concentration
-more sensitive than competitive EIA
-one of the most common immunoassays
273
EIA formats - ELISA - used to detect?
antibodies to viruses, e.g., HIV, hepatitis A (HAV), HCV, EBV
274
EIA formats - Sandwich ELISA or capture assay - description
heterogeneous, noncompetitive, indirect
275
EIA formats - Sandwich ELISA or capture assay - principle
-antibody attached to solid phase
-antigen in specimen attaches
-enzyme-labeled antibody added, attaches to different determinant
-enzymatic activity directly proportional to amount of antigen in sample
276
EIA formats - Sandwich ELISA or capture assay - antigen must have?
multiple determinants
277
EIA formats - Sandwich ELISA or capture assay - used to measure?
-hormones
-proteins
-detect tumor markers
-viruses
-parasites
-fungi
278
EIA formats - Sandwich ELISA or capture assay - high concentration of antigen can cause?
Hook effect - too much antigen for binding sites so undiluted sample has lower absorbance than dilutions
279
EIA formats - Rapid ELISA (lateral flow) - description
membrane based
280
EIA formats - Rapid ELISA (lateral flow) - principle
-reagent antigen or antibody bound to membrane in single use cassette
-sample added
-presence of ag-ab complex indicated by colored reaction
281
EIA formats - Rapid ELISA (lateral flow) - examples
pregnancy tests, cardiac troponin, SARS-CoV 2
-usually qualitative and designed primarily for POCT or at home testing
282
EIA formats - Enzyme-multiplied immunoassay technique (EMIT) - description
homogeneous
283
EIA formats - Enzyme-multiplied immunoassay technique (EMIT) - principle
-antigen in specimens & enzyme-labeled antigen compete for binding sites on reagent antibody
-when enzyme-labeled antigen binds, enzyme activity inhibited
-enzyme activity is directly proportional to concentration of antigen in specimen
284
EIA formats - Enzyme-multiplied immunoassay technique (EMIT) - used for?
determination of low molecular weight analytes not readily measured by other methods, e.g., drugs and some hormones
-automated
285
Fluorescent immunoassays (FIA) - direct fluorescent antibody (DFA) staining - principle
-specimen on glass slide overlaid with fluorescein-labeled antibody
-if corresponding antigen is present, labeled antibody binds
-fluorescence observed with fluorescent microscope
286
Fluorescent immunoassays (FIA) - direct fluorescent antibody (DFA) staining - detects?
antigen
287
Fluorescent immunoassays (FIA) - direct fluorescent antibody (DFA) staining - fluorescent labels
Fluorescein isothiocyanate or rhodamine B isothiocyanate
288
Fluorescent immunoassays (FIA) - direct fluorescent antibody (DFA) staining - examples of analytes
bacteria, viral antigen
289
Fluorescent immunoassays (FIA) - indirect fluorescent antibody (IFA) staining - principle
-reagent antigen on glass slide overlaid with patient serum
-if corresponding antibody is present in serum, attached to the antigen
-when fluorescein-labeled antihuman globulin is added, attaches to antibody
-fluorescence observed with fluorescent microscope
290
Fluorescent immunoassays (FIA) - indirect fluorescent antibody (IFA) staining - detects?
antibodies in serum
"Sandwich technique"
291
Fluorescent immunoassays (FIA) - indirect fluorescent antibody (IFA) staining - examples of analytes
-antinuclear antibody (ANA)
-fluorescent treponemal antibody (FTA)
292
Fluorescent immunoassays (FIA) - fluorescence polarization immunoassay (FPIA) - principle
-labeled antigen competes with antigen in specimen for sites on reagent antibody
-free labeled antigen rotates rapidly, emits little polarized light
-bound labeled antigen rotates more slowly, emits more polarized light
-amount of polarized light is inversely proportional to concentration of antigen in specimen
293
Fluorescent immunoassays (FIA) - fluorescence polarization immunoassay (FPIA):
-competitive or noncompetitive?
-heterogeneous or homogenerous?
-competitive
-homogeneous
294
Fluorescent immunoassays (FIA) - fluorescence polarization immunoassay (FPIA) - examples of analytes
therapeutic drugs, hormones
295
Comparison of labeled immunoassays - EIA - labels
-alkaline phosphatase
-horseradish peroxidase
-Alpha-D-galactosidase
-glucose-6-phosphate dehydrogenase
296
Comparison of labeled immunoassays - EIA - detection
enzymes react with substrate to produce color change
297
Comparison of labeled immunoassays - EIA - type(s) of assays available
-mostly noncompetitive now
-heterogenous or homogeneous
298
Comparison of labeled immunoassays - EIA - advantages
-sensitivity
-specificity
-no health hazard or disposal problems
-reagents with long shelf life
-can be automated
299
Comparison of labeled immunoassays - EIA - disadvantages
-natural inhibitors in some specimens
-cross reactivity of some substances
300
Comparison of labeled immunoassays - EIA - use
common
301
Comparison of labeled immunoassays - FIA - labels
-fluorescein
-rhodamine
302
Comparison of labeled immunoassays - FIA - detection
fluorochromes absorb energy from light source, convert to longer wavelength (lower energy)
303
Comparison of labeled immunoassays - FIA - type(s) of assays available
-usually competitive
-heterogeneous & homogeneous
304
Comparison of labeled immunoassays - FIA - advantages
-sensitivity
-specificity
-no health hazard or disposal problems
-reagent with long shelf life
-automated
305
Comparison of labeled immunoassays - FIA - disadvantages
-autofluorescence from organic substances in serum
-nonspecific binding to substances in serum
-expensive, dedicated instrumentation
306
Comparison of labeled immunoassays - FIA - use
common
307
Comparison of labeled immunoassays - Chemiluminescent Immunoassay (CIA) - labels
-luminol
-acridinium esters
-ruthenium derivatives
-nitrophenyl oxalates
308
Comparison of labeled immunoassays - Chemiluminescent Immunoassay (CIA) - detection
chemiluminescent molecules produce light from chemical reaction
309
Comparison of labeled immunoassays - Chemiluminescent Immunoassay (CIA) - type(s) of assays available
-competitive & noncompetitive
-heterogeneous & homogeneous
310
Comparison of labeled immunoassays - Chemiluminescent Immunoassay (CIA) - advantages
-sensitivity
-specificity
-no health hazard or disposal problems
-reagent with long shelf life
-automated
311
Comparison of labeled immunoassays - Chemiluminescent Immunoassay (CIA) - disadvantages
quenching of light emission by some biological materials
312
Comparison of labeled immunoassays - Chemiluminescent Immunoassay (CIA) - use
common
313
Nontreponemal tests for syphilis - VDRL - method
flocculation
314
Nontreponemal tests for syphilis - VDRL - detects
reagin
(antibody against cardiolipin that is in serum of patients with syphilis)
315
Nontreponemal tests for syphilis - VDRL - antigen
cardiolipin
316
Nontreponemal tests for syphilis - VDRL - positive reaction
microscopic clumps
317
Nontreponemal tests for syphilis - VDRL - specimen(s)
-inactivated serum
-CSF
318
Nontreponemal tests for syphilis - VDRL - reactivity during disease
-Primary stage: may be negative
-Secondary or early late stages: titers usually peak
-more rapid decline with treatment
-becomes non-reactive in 1-2 years following successful treatment
319
Nontreponemal tests for syphilis - VDRL - false positives
Biologic false positives:
--infectious mono (IM)
--infectious hepatitis
--malaria
--leprosy
--lupus erythematosus
--RA
--advanced age
--pregnancy
Reactive in other treponemal infections such as yaws & pinta.
320
Nontreponemal tests for syphilis - VDRL - reactives should be confirmed by?
treponemal test
321
Nontreponemal tests for syphilis - VDRL - replaced by?
RPR for serum
322
Nontreponemal tests for syphilis - VDRL - CSF
diagnosis of neurosyphilis
323
Nontreponemal tests for syphilis - RPR - method
flocculation
324
Nontreponemal tests for syphilis - RPR - detects
reagin
325
Nontreponemal tests for syphilis - RPR - antigen
cardiolipin with charcoal
326
Nontreponemal tests for syphilis - RPR - positive reaction
macroscopic agglutination
327
Nontreponemal tests for syphilis - RPR - specimen(s)
-serum (inactivation not required)
-plasma
328
Nontreponemal tests for syphilis - RPR - reactivity during disease
-Primary stage: may be negative
-Secondary or early late stages: titers usually peak
-more rapid decline with treatment
-becomes non-reactive in 1-2 years following successful treatment
329
Nontreponemal tests for syphilis - RPR - reactives should be confirmed by?
treponemal test
330
Treponemal tests for syphilis - Fluorescent treponemal antibody absorption (FTA-ABS) - detects
antibody to *T. pallidum*
331
Treponemal tests for syphilis - Fluorescent treponemal antibody absorption (FTA-ABS) - reagent(s)
-sorbent (nonpathologic treponemes - Reiter strain)
-slides with Nichols strain of *T. pallidum*
-fluorescein-labeled antihuman globulin
332
Treponemal tests for syphilis - Fluorescent treponemal antibody absorption (FTA-ABS) - positive reaction
fluorescence
333
Treponemal tests for syphilis - Fluorescent treponemal antibody absorption (FTA-ABS) - specimen(s)
-serum
-CSF
334
Treponemal tests for syphilis - Fluorescent treponemal antibody absorption (FTA-ABS) - reactivity during disease
-usually positive before non-treponemal tests
-some false negatives in primary syphilis
-usually positive for life
335
Treponemal tests for syphilis - *Treponema pallidum* particle agglutination (TP-PA) - detects
antibody to *T. pallidum*
336
Treponemal tests for syphilis - *Treponema pallidum* particle agglutination (TP-PA) - reagent(s)
colored gelatin particles coated with treponemal antigen
337
Treponemal tests for syphilis - *Treponema pallidum* particle agglutination (TP-PA) - positive reaction
-agglutination of sensitized gel particles
-smooth mat over surface of well
338
Treponemal tests for syphilis - *Treponema pallidum* particle agglutination (TP-PA) - specimen(s)
serum
339
Treponemal tests for syphilis - *Treponema pallidum* particle agglutination (TP-PA) - reactivity during disease
-not as sensitive in primary syphilis as FTA
-sensitivity close to 100% in secondary syphilis
-usually positive in late stages
340
Treponemal tests for syphilis - Antibody capture enzyme-linked immunosorbent assay (ELISA) - detects
antibody to *T. pallidum*
341
Treponemal tests for syphilis - Antibody capture enzyme-linked immunosorbent assay (ELISA) - reagent(s)
enzyme-labeled treponemal antigen
342
Treponemal tests for syphilis - Antibody capture enzyme-linked immunosorbent assay (ELISA) - positive reaction
color development following addition of substrate
343
Treponemal tests for syphilis - Antibody capture enzyme-linked immunosorbent assay (ELISA) - specimen(s)
serum
344
Treponemal tests for syphilis - Antibody capture enzyme-linked immunosorbent assay (ELISA) - reactivity during disease
high sensitivity
345
Treponemal tests for syphilis - Antibody capture enzyme-linked immunosorbent assay (ELISA) - false positives
-fewer than nontreponemal tests
-reactive with other treponemal diseases (e.g., yaws, pinta)
346
Treponemal tests for syphilis - Antibody capture enzyme-linked immunosorbent assay (ELISA) - used for?
screening & confirmation of reactive nontreponemal tests
347
Treponemal tests for syphilis - Antibody capture enzyme-linked immunosorbent assay (ELISA) - used for screening
reactives should be confirmed with nontreponemal test (reverse sequence screening), followed by TP-PA or FTA-ABS if nontreponemal test is nonreactive
348
Treponemal tests for syphilis - Antibody capture enzyme-linked immunosorbent assay (ELISA) - Dx of congenital syphilis
IgM capture assay
349
Treponemal tests for syphilis - Fluorescent treponemal antibody absorption (FTA-ABS) - false positives
-fewer than nontreponemal tests
-reactive with other treponemal diseases, e.g., yaws, pinta
350
Treponemal tests for syphilis - Fluorescent treponemal antibody absorption (FTA-ABS) - what does absorbent remove?
non-specific antibodies
351
Treponemal tests for syphilis - Fluorescent treponemal antibody absorption (FTA-ABS) - used to confirm?
reactive nontreponemal tests
352
Treponemal tests for syphilis - Fluorescent treponemal antibody absorption (FTA-ABS) - not good for?
treatment monitoring
353
Treponemal tests for syphilis - *Treponema pallidum* particle agglutination (TP-PA) - false positives
fewer than nontreponemal tests
354
Treponemal tests for syphilis - *Treponema pallidum* particle agglutination (TP-PA) - used to confirm?
reactive nontreponemal tests
355
Treponemal tests for syphilis - *Treponema pallidum* particle agglutination (TP-PA) - positive result
a smooth mat will form in the base of the well of a microtitre plate, indicating a positive result
356
Treponemal tests for syphilis - *Treponema pallidum* particle agglutination (TP-PA) - not good for?
treatment monitoring
357
Interpretation of syphilis test results:
RPR: reactive
FTA: reactive
Positive for syphilis
358
Interpretation of syphilis test results:
RPR: reactive
FTA: non-reactive
Negative for syphilis
359
Interpretation of syphilis test results:
ELISA: reactive
RPR: reactive
Positive for syphilis
360
Interpretation of syphilis test results:
ELISA: reactive
RPR: non-reactive
FTA-ABS: reactive
late, latent, or previous syphilis
361
Serological tests for other bacterial infections - Anti-streptolysin O (ASO) - diagnosis
Sequelae of GAS infection: rheumatic fever, poststreptococcal glomerulonephritis
362
Serological tests for other bacterial infections - Anti-streptolysin O (ASO) - common method(s)
nephelometry
363
Serological tests for other bacterial infections - Anti-streptolysin O (ASO) - antigen used?
recombinant streptolysin antigen
364
Serological tests for other bacterial infections - Anti-streptolysin O (ASO) - positive result
if antibody present, antigen-antibody complexes form, & increased light scatter
365
Serological tests for other bacterial infections - Anti-DNase B - diagnosis
Sequelae of GAS infections: rheumatic fever, glomerulonephritis following skin infection, i.e., impetigo
366
Serological tests for other bacterial infections - Anti-DNase B - common method(s)
EIA, nephelometry
367
Serological tests for other bacterial infections - Anti-DNase B - advantages
-highly specific
-may be positive when ASO is negative
368
Serological tests for other bacterial infections - Streptozyme - diagnosis
Sequelae of GAS infection
369
Serological tests for other bacterial infections - Streptozyme - common method(s)
slide agglutination
370
Serological tests for other bacterial infections - Streptozyme - principle
uses sheep RBCs coated with several streptococcal antigens
371
Serological tests for other bacterial infections - Streptozyme - disadvantages
-more false positives & false negatives
Should be used in conjunction with ASO & anti-DNase
-serial titers should be performed
372
Serological tests for other bacterial infections - *Helicobacter pylori* antibody - diagnosis
gastric & duodenal ulcers caused by *H. pylori*
373
Serological tests for other bacterial infections - *Helicobacter pylori* antibody - common method(s)
-method of choice: ELISA
-rapid tests, PCR available
374
Serological tests for other bacterial infections - *Helicobacter pylori* antibody - detect what Ig?
IgG
375
Serological tests for other bacterial infections - *Helicobacter pylori* antibody - successful treatment
25% decrease in titer
376
Serological tests for other bacterial infections - *Helicobacter pylori* antibody - antibody lifespan
years
377
Serological tests for other bacterial infections - *Helicobacter pylori* antibody - positive rapid tests should be confirmed by?
ELISA
378
Serological tests for other bacterial infections - *Mycoplasma pneumoniae* antibody - diagnosis
primary atypical pneumonia (PAP)
379
Serological tests for other bacterial infections - *Mycoplasma pneumoniae* antibody - common method(s)
-most common: EIA
-also agglutination, IFA
-molecular methods available
380
Serological tests for other bacterial infections - *Mycoplasma pneumoniae* antibody - antibodies tested?
IgM & IgG antibodies
381
Serological tests for other bacterial infections - Rickettsial antibody - diagnosis
-typhus
-rocky mountain spotted fever
-other rickettsial infections
382
Serological tests for other bacterial infections - Rickettsial antibody - common method(s)
-Gold standard: IFA, micro-IFA
-PCR available
383
Serological tests for infectious mononucleosis (IM) - heterophile antibodies - specificity
-non-specific antibodies that agglutinate horse, sheep, & bovine RBCs
-heterophile antibodies are antibodies that react with similar antigens from different species
384
Serological tests for infectious mononucleosis (IM) - heterophile antibodies - occurrence
-90% of patients develop in 1st month of illness
-can persist for 1 year
-negative in 10% of adults & up to 50% of children with IM
-if symptomatic & heterophile negative, test for EBV-specific antibodies
385
Serological tests for infectious mononucleosis (IM) - heterophile antibodies - tests
-rapid latex agglutination
-solid-phase immunoassay
-antigen is purified bovine RBC extract
-screening tests
386
Serological tests for infectious mononucleosis (IM) - EBV-specific antibodies - specificity
-specific antibodies against EBV antigens present in different phases of infection:
--early: early antigen (EA)
--late: viral capsid antigen (VCA)
--latent: EBV nuclear antigen (EBNA)
387
Serological tests for infectious mononucleosis (IM) - EBV-specific antibodies - occurrence
-anti-VCA IgM: appears at onset of symptoms, disappears in 3 months
-anti-VCA IgG: appears at onset of symptoms, persists for life
-anti-EBNA: present during convalescence
Acute infection:
-anti-VCA IgM,
-anti-VCA IgG
-anti-EA
Past infection:
-anti-EBNA
-anti-VCA IgG
-negative anti-VCA IgM
388
Serological tests for infectious mononucleosis (IM) - EBV-specific antibodies - tests
-IFA - gold standard but time consuming & harder to interpret
-ELISA
-CIA
-molecular tests can be used for immunocompromised patients who don't produce antibodies
389
Hepatitis tests - Hepatitis A - Total anti-HAV - significance
past infection & immunity
390
Hepatitis tests - Hepatitis A - IgM anti-HAV - significance
acute infection
391
Hepatitis tests - Hepatitis A - HAV RNA - significance
current infection
392
Hepatitis tests - Hepatitis A - HAV RNA - used to detect?
HAV in food and water
393
Hepatitis tests - Hepatitis B - Hepatitis B surface antigen (HBsAg) - significance
acute or chronic infection, infectivity
394
Hepatitis tests - Hepatitis B - Hepatitis B surface antigen (HBsAg) - confirmation of positive
repeat testing and another assay such as hepatitis B DNA PCR
395
What is the first serological marker to appear during early acute infection of Hepatitis B?
Hepatitis B surface antigen (HBsAg)
396
Hepatitis tests - Hepatitis B - Hepatitis B e antigen (HBeAg) - significance
acute or chronic infection
397
Hepatitis tests - Hepatitis B - Hepatitis B e antigen (HBeAg) - indicative of?
high degree of infectivity
398
Hepatitis tests - Hepatitis B - Total anti-Hepatitis B core (HBc) - significance
current or past infection or carrier
399
Hepatitis tests - Hepatitis B - Total anti-Hepatitis B core (HBc) - prominent immunoglobulin
IgG, which persists for life
400
Hepatitis tests - Hepatitis B - IgM anti-HBc - significance
current or recent infection
401
Hepatitis tests - Hepatitis B - IgM anti-HBc - useful for detecting?
HBV infection when HBsAg is no longer detectable ("window period")
402
What is the first antibody to appear in hepatitis B?
IgM anti-HBc
403
What tests are used to screen blood donors for hepatitis B?
HBsAG and IgM anti-HBc
404
Hepatitis tests - Hepatitis B - Anti-HBe - significance
recovery, reduced infectivity
405
Hepatitis tests - Hepatitis B - Anti-HBs - significance
recovery & immunity
406
What antibody develops following immunization for hepatitis B?
Anti-HBs
407
Hepatitis tests - Hepatitis B - Hepatitis B virus (HBV) DNA - significance
current infection
408
What is detectable 21 days before HBsAg in hepatitis B?
Hepatitis B virus (HBV) DNA
409
Hepatitis tests - Hepatitis C - Anti-HCVh - significance
acute, chronic, or previous infection
410
Hepatitis tests - Hepatitis C - HCV RNA - significance
current infection
411
Hepatitis tests - Hepatitis C - HCV RNA - used for?
-viral load testing
-blood/organ donor screening
-HCV genotyping to determine optimal treatment
412
Hepatitis tests - Hepatitis D - Hepatitis D (HDV) (delta hepatitis) - IgM anti-HDV - significance
acute or chronic infection
413
Hepatitis tests - Hepatitis D - Hepatitis D (HDV) (delta hepatitis) - IgM anti-HDV - a defective virus that can only occur in the presence of?
HBV
414
Hepatitis tests - Hepatitis D - Hepatitis D (HDV) (delta hepatitis) - IgG anti-HDV - significance
recovery or chronic infection
415
Hepatitis tests - Hepatitis D - Hepatitis D (HDV) (delta hepatitis) - HDV RNA - significance
current infection
416
Hepatitis tests - Hepatitis D - Hepatitis D (HDV) (delta hepatitis) - HDV RNA - marker of?
viral replication
417
Hepatitis tests - Hepatitis D - Hepatitis D (HDV) (delta hepatitis) - HDV RNA - used to?
monitor therapy
418
Hepatitis tests - Hepatitis E - tests
tests are not currently approved by the FDA for use in the US
419
Hepatitis serological profiles - Acute Hepatitis A
IgM anti-HAV +
420
Hepatitis serological profiles - Recovery from Hepatitis A
Total anti-HAV +
421
Hepatitis serological profiles - Acute Hepatitis B
HBsAg +
Total anti-HBc +
IgM anti-HBc +
Anti-HBs -
422
Hepatitis serological profiles - Recovery from Hepatitis B
HBs Ag -
Total anti-HBc +
Anti-HBs +
423
Hepatitis serological profiles - Chronic Hepatitis B/Carrier
HBsAg +
Total anti-HBc +
IgM anti-HBc -
Anti-HBs -
424
Hepatitis serological profiles - Hepatitis B immunization
HBsAg -
Anti-HBc -
Anti-HBs +
425
Appearance of HIV markers - Viral RNA
detectable within days of infection
426
Appearance of HIV markers - p24 ag
-core coat for nucleic acids
-detectable in 2-3 weeks
-becomes undetectable as antibodies develop, then detectable again in late stages as immune system fails & virus replicates
427
Appearance of HIV markers - IgM ab
-usually detectable in 2-8 weeks
-transient
-peaks in about 1-2 weeks
-undetectable about 1-2 weeks later
428
Appearance of HIV markers - IgG ab
-detectable shortly after IgM
-gradual increase in titer over several months
-long lasting
429
HIV screening tests - ELISA/CLIA - 1st generation - detect
IgG ab to HIV-1
430
HIV screening tests - ELISA/CLIA - 1st generation - window period
6-12 weeks
431
HIV screening tests - ELISA/CLIA - 2nd generation - detect
IgG ab to HIV-1/2
432
HIV screening tests - ELISA/CLIA - 2nd generation - window period
6-12 weeks
433
HIV screening tests - ELISA/CLIA - 3rd generation - detect
IgG & IgM ab to HIV-1/2
434
HIV screening tests - ELISA/CLIA - 3rd generation - window period
3-4 weeks
435
HIV screening tests - ELISA/CLIA - 4th generation - detect
IgG & IgM ab to HIV-1/2 and pg24 ag
436
HIV screening tests - ELISA/CLIA - 4th generation - window period
2 weeks
437
HIV screening tests - ELISA/CLIA - 5th generation - detect
-IgG & IgM ab to HIV but differentiates HIV-1 from HIV-2
-also detects p24 ag
438
HIV screening tests - ELISA/CLIA - acute infection
P24 ag without HIV ab
439
HIV screening tests - ELISA/CLIA - establish infection
P24 ag & HIV ab
440
HIV screening tests - rapid tests - detects
IgG & IgM ab to HIV
441
HIV screening tests - rapid tests - window period
4-12 weeks
442
HIV screening tests - rapid tests - assays
immunochromatographic
443
HIV screening tests - rapid tests - samples
whole blood, serum, oral fluid
444
HIV screening tests - Nucleic acid amplification testing (NAAT) - detects
HIV RNA
445
HIV screening tests - Nucleic acid amplification testing (NAAT) - window period
5 days
446
List the causes of false positives with HIV-antibody ELISA testing.
-heat inactivation of serum
-repeated freezing/thawing of serum
-autoantibodies
-multiple pregnancies
-liver disease
-administration of Ig
-administration of certain vaccines
-some malignancies
447
List the causes of false negatives with HIV-antibody ELISA testing.
-blood drawn before seroconversion (window period)
-hypogammaglobulinemia
-immunosuppressive therapy
-strain of HIV not detected by assay
-technical errors
448
HIV supplemental tests - Western blot (WB) - detects
antibody to HIV
449
HIV supplemental tests - Western blot (WB) - positive
Report positive if at least 2 of the following 3 bands are present:
-p24
-gp41
-gp1220/160
450
HIV supplemental tests - Western blot (WB) - negative
NAAT required following negative or indeterminant results
451
HIV supplemental tests - Western blot (WB) - disadvantages
-time-consuming
-difficult to interpret
452
HIV supplemental tests - NAAT - detects
HIV RNA
453
HIV supplemental tests - NAAT - useful when?
serology results are inconclusive
454
Tests to stage and monitor HIV - CD4 T-cell count
-HIV infects CD4 cells
-Number declines as disease progresses
-<200/uL defines stage 3 infection
-also used to monitor therapy
-perform every 3-6 months
-flow cytometry is gold standard
455
Tests to stage and monitor HIV - HIV-1 viral load assays: PCR (RT-PCR and qPCR); branched chain DNA assay (bDNA)
-quantitative methods to determine plasma HIV RNA
-used to predict disease progression, determine when to start antiretroviral therapy, & monitor response to therapy
-qPCR most frequently performed
-bDNA assays are used in labs with high testing volumes
-test 2-8 weeks after start of therapy & then every 3-4 months
-same assay should be used in order to assess changes
456
Screening tests for Systemic Lupus Erythematosus (SLE) - Antinuclear antibody (ANA) - method
-indirect immunofluorescence (IIF)
-substrate is human epithelial cell line (Hep-2)
-high sensitivity (95-100%) but low specificity
-dilutions tested to eliminate low titer reaction in normal population
-cutoff dilution to report positive usually >=1:80
-endpoint titer may be reported
-generally higher in SLE
457
Screening tests for Systemic Lupus Erythematosus (SLE) - Antinuclear antibody (ANA) - detects?
auto-antibodies to nuclear antigen - staining patterns reported
458
Screening tests for Systemic Lupus Erythematosus (SLE) - Antinuclear antibody (ANA) - disadvantages
-labor intensive
-subjective
459
Screening tests for Systemic Lupus Erythematosus (SLE) - Complement (C3) EIA - method
EIA
460
Screening tests for Systemic Lupus Erythematosus (SLE) - Complement (C3) EIA - C3
C3 is turned over rapidly in SLE patients, especially during flare-ups, will see a decrease in serum C3 levels
461
Screening tests for Systemic Lupus Erythematosus (SLE) - urinalysis - method
dipstick
462
Screening tests for Systemic Lupus Erythematosus (SLE) - urinalysis - looking for?
RBCs and protein to screen for kidney damage causes by Ag-autoAb complexes
463
Tests for specific antinuclear antibodies (ANA) - Anti-dsDNA - sensitivity for SLE
low
464
Tests for specific antinuclear antibodies (ANA) - Anti-dsDNA - specificity for SLE
high
(uncommon in other diseases or normal individuals)
465
What antibody is the most specific antibody for SLE?
Anti-dsDNA
466
Tests for specific antinuclear antibodies (ANA) - Anti-dsDNA - titers
correlate with disease activity
467
Tests for specific antinuclear antibodies (ANA) - Anti-dsDNA - IIF patterns
peripheral or homogeneous fluorescent pattern
468
Tests for specific antinuclear antibodies (ANA) - Anti-Sm - sensitivity for SLE
low
469
Tests for specific antinuclear antibodies (ANA) - Anti-Sm - specificity for SLE
high
470
Tests for specific antinuclear antibodies (ANA) - Anti-Sm - IIF pattern
coarsely speckled pattern
471
Tests for specific antinuclear antibodies (ANA) - Anti-Sm - test methods
EIA, immunodiffusion, IIF
472
Tests for specific antinuclear antibodies (ANA) - Anti-dsDNA - test methods
EIA, IIF
473
Tests for specific antinuclear antibodies (ANA) - Antihistone, anti-DNP, anti-SS-A/R0, anti-SS-B/La, anti-nRNP - sensitivity
low
474
Tests for specific antinuclear antibodies (ANA) - Antihistone, anti-DNP, anti-SS-A/R0, anti-SS-B/La, anti-nRNP - specificity for SLE
low
475
Tests for specific antinuclear antibodies (ANA) - Antihistone, anti-DNP, anti-SS-A/R0, anti-SS-B/La, anti-nRNP - diagnosis
-generally not useful for Dx of SLE
-used to Dx other connective tissue diseases (Sjogren syndrome)
476
Tests for specific antinuclear antibodies (ANA) - Antihistone, anti-DNP, anti-SS-A/R0, anti-SS-B/La, anti-nRNP - method
IIF, EIA, immunodiffusion
477
Tests for specific antinuclear antibodies (ANA) - Extractable nuclear antigen (ENA) - sensitivity for SLE
low
478
Tests for specific antinuclear antibodies (ANA) - Extractable nuclear antigen (ENA) - specificity for SLE
anti-Sm is specific for SLE
479
Tests for specific antinuclear antibodies (ANA) - Extractable nuclear antigen (ENA) - method
immunodiffusion (Ouchterlony double diffusion) test panel that typically tests for antibodies to Smith (Sm), SS-A/R0, SS-B/La, Ribonucleoprotein (RNP)
-precipitin lines of identity/nonidentity
-new method: multiplex bead assay - immunoassay using specific antigen-coated beads & flow cytometry to detect multiple (currently 6-13) ANAs simultaneously
480
Serological tests for Rheumatoid Arthritis (RA) - Rheumatoid factor (RF) - common method(s)
agglutination, ELISA, nephelometry
481
Serological tests for Rheumatoid Arthritis (RA) - Rheumatoid factor (RF) - autoantibody
autoantibody (usually IgM) against IgG
482
Serological tests for Rheumatoid Arthritis (RA) - Rheumatoid factor (RF) - specificity
low
483
Serological tests for Rheumatoid Arthritis (RA) - Rheumatoid factor (RF) - agglutination tests
only detect IgM RF
484
Serological tests for Rheumatoid Arthritis (RA) - Rheumatoid factor (RF) - ELISA & nephelometry
detect IgM, IgA, & IgG classes of RF
485
Serological tests for Rheumatoid Arthritis (RA) - Rheumatoid factor (RF) - positive in what percentage of patients with RA?
70-80%
486
Serological tests for Rheumatoid Arthritis (RA) - Anti-cyclic citrullinated peptide antibody (Anti-CCP) - common method(s)
ELISA
487
Serological tests for Rheumatoid Arthritis (RA) - Anti-cyclic citrullinated peptide antibody (Anti-CCP) - specificity
more specific for RA than RF
488
Autoimmune diseases - Systemic Lupus Erythematosus (SLE) - target cells and tissues
Multiple: kidneys, joints, skin, brain, heart, lungs
489
Autoimmune diseases - Systemic Lupus Erythematosus (SLE) - laboratory findings
-autoantibodies to dsDNA and other nuclear components
-also see decreased serum C3
-increased CRP & ESR
-RBCs/protein in ruine
490
Autoimmune diseases - Systemic Lupus Erythematosus (SLE) - abnormal CBC values
-decreased HGB & HCT
-low WBC and platelet count
491
Autoimmune diseases - Rheumatoid Arthritis (RA) - target cells and tissues
joints, bone, and other connective tissue
492
Autoimmune diseases - Rheumatoid Arthritis (RA) - laboratory findings
-anti-CCP most diagnostic
-rheumatoid factor
-positive ANA titer
-elevated CRP, ESR
-decreased C3
used to monitor treatment
493
Autoimmune diseases - Wegener Granulomatosis - target cells and tissues
upper respiratory system, lungs, and blood vessels
494
Autoimmune diseases - Wegener Granulomatosis - laboratory findings
-positive antineutrophil cytoplasmic antibody (ANCAs)
-glomerulonephritis
495
Autoimmune diseases - Wegener Granulomatosis - severity
rare but severe due to chronic activation of neutrophils, T cells, and B cells
496
Autoimmune diseases - Scleroderma - target cells and tissues
skin and blood vessels - fibrosis can occur in vessels of most organs
497
Autoimmune diseases - Scleroderma - laboratory findings
-Scl-70 autoantibodies
-speckled/nucleolar ANA pattern
-Raynaud's phenomenon common
498
Autoimmune diseases - Sjogren Syndrome - target cells and tissues
lacrimal and salivary glands
499
Autoimmune diseases - Sjogren Syndrome - laboratory findings
autoantibodies toward RNA complexed with cellular proteins (SS-A/Ro and SS-B/La)
500
Autoimmune diseases - Sjogren Syndrome - can occur with what other diseases?
SLE and RA
501
Autoimmune diseases - Graves' Disease - target cells and tissues
thyroid gland (commonly TSH receptors)
502
Autoimmune diseases - Graves' Disease - laboratory findings
-decreased TSH
-increased T4
-TSH receptor autoantibodies
-may see thyroglobulin & TPO autoantibodies
503
Autoimmune diseases - Graves' Disease - diagnostic in 99% of patients?
TSH receptor autoantibodies
504
Autoimmune diseases - Hashimoto Thyroiditis - target cells and tissues
thyroid gland (eipthelial cells)
505
Autoimmune diseases - Hashimoto Thyroiditis - laboratory findings
-increased TSH
-decreased T4
-TPO & thyroglobulin autoantibodies in most patients
506
Autoimmune diseases - Hashimoto Thyroiditis - diagnostic?
microsomal autoantibodies
507
Immunodeficiency diseases - Severe Combined Immunodeficiency (SCID) - immune component deficient
adaptive arm, IL-2 receptor mutation
508
Immunodeficiency diseases - Severe Combined Immunodeficiency (SCID) - laboratory findings
decreased and/or non-functional T cells and B cells
509
Immunodeficiency diseases - Severe Combined Immunodeficiency (SCID) - confirmation
genetic tests
510
Immunodeficiency diseases - Wiskott-Aldrich Syndrome - immune component deficient
cellular arm of immune system (mainly T cells but then B cells can't form antibodies)
511
Immunodeficiency diseases - Wiskott-Aldrich Syndrome - laboratory findings
-decreased platelet numbers and size
-decreased IgM (to ABO antigens, can be diagnostic)
-elevated serum alpha fetoprotein (AFP)
512
Immunodeficiency diseases - Wiskott-Aldrich Syndrome - patients often have?
severe eczema
513
Immunodeficiency diseases - DiGeorge Anomaly - immune component deficient
chromosome 22 mutation, defective thymus or lack of thymus
514
Immunodeficiency diseases - DiGeorge Anomaly - laboratory findings
partial or complete lack of T cells
515
Immunodeficiency diseases - Ataxia Telangiectasia (AT) - immune component deficient
chromosomal breaks occur, inhibiting VDJ rearrangement for T and B cells
516
Immunodeficiency diseases - Ataxia Telangiectasia (AT) - laboratory findings
-decreased circulating T cells
-decreased levels of IgA, IgE, and IgG2
-increased serum AFP
517
Immunodeficiency diseases - Ataxia Telangiectasia (AT) - physical manifestations
ataxia and capillary swelling/red blotches
518
Immunodeficiency diseases - X-linked Bruton Tyrosine Kinase Deficiency - immune component deficient
antibody immunodeficiency, lack of CD19+ cells and all subsequent cells (plasma and memory cells)
519
Immunodeficiency diseases - X-linked Bruton Tyrosine Kinase Deficiency - laboratory findings
-lack of CD19+ cells via flow cytometry
-decreased or lack of IgA, IgE, IgG, IgM
520
Immunodeficiency diseases - Selective IgA Deficiency - immune component deficient
IgA only is deficient
521
Immunodeficiency diseases - Selective IgA Deficiency - laboratory findings
lack of serum IgA
522
Immunodeficiency diseases - Selective IgA Deficiency - physical findings
recurrent respiratory and GI infections
523
Immunodeficiency diseases - Chediak Higashi Syndrome - immune component deficient
NK cells/neutrophils
524
Immunodeficiency diseases - Chediak Higashi Syndrome - laboratory findings
-differential shows leukocytes with enlarged granules
-increased acute phase proteins and cytokines
525
Immunodeficiency diseases - Chronic Granulomatous Disease - immune component deficient
neutrophil microbiocidal function
526
Immunodeficiency diseases - Chronic Granulomatous Disease - laboratory findings
DHR/flow cytometry (decreased fluorescence)
527
Immunodeficiency diseases - Chronic Granulomatous Disease - increased susceptibility to?
pyogenic infections
528
Immunodeficiency diseases - Leukocyte Adhesion Deficiency - immune component deficient
CD18 on phagocytic cells
529
Immunodeficiency diseases - Leukocyte Adhesion Deficiency - laboratory findings
decreased CD18 on dendritic cells (measured by flow cytometry)
530
Immunodeficiency diseases - Leukocyte Adhesion Deficiency - physical findings
-delayed wound healing
-chronic skin, intestinal, and respiratory tract infections
531
Interpretation of serological tests -
titer concentration
>=4-fold increase in titer from acute to convalescent specimen drawn 10-14 days later is diagnostic
532
Interpretation of serological tests - IgM ab
sign of recent infection
533
Interpretation of serological tests - IgG ab
sign of immunity
534
Interpretation of serological tests - IgG ab in newborn
is maternal antibody
535
How would you prepare a 5% suspension of human group O RBCs?
5% = 5 mL per 100 mL
Mix 5 mL of packed RBCs + 95 mL of buffer.
For a smaller amount: 0.5 mL of packed RBCs + 9.5 mL buffer
Any 1:20 dilution could be used (5:100 = 1:20)
536
How would you prepare 5 mL of a 1:10 dilution of serum?
(1/10) = (x/5)
10x = 5
x = 0.5 mL
0.5 mL diluted to 5 mL is a 1:10 dilution, so mix 0.5 mL serum + 4.5 mL of buffer
537
How would you prepare 10 mL of a 1:100 dilution from a 1:10 dilution?
A. Determine the dilution factor to make a 1:100 dilution from a 1:10 dilution:
1/10 x 1/x = 1/100
1/10x = 1/100
10x = 100
x = 10
A 1:10 dilution of a 1:10 dilution yields a 1:100 dilution (1/10 x1/10 = 1/100)
B. Determine how to make 10 mL of a 1:10 dilution:
1:10 dilution is 1 part + 9 parts
To make 10 mL, mix 1 mL of solution + 9 mL of buffer.
To make 10 mL of a 1:100 dilution from a 1:10 dilution, mix 1 mL of the 1:10 dilution + 9 mL of buffer
538
What is the dilution in tube 4 of a 2-fold serial dilution, if tube 1 is undiluted?
1 x 1/2 x 1/2 x 1/2 = 1/8
539
Which cell of the innate immune system has granules that contain bactericidal enzymes?
A. Dendritic cell
B. Neutrophil
C. T cell
D. Mast cell
B. Neutrophil
540
Which part of an antibody molecule is responsible for complement fixation and opsonization?
A. Fc fragment
B. Fab fragment
C. Light chain
D. Joining (J) chain
A. Fc fragment
541
Which hypersensitivity reaction is predominantly mediated by T cells?
A. Type I
B. Type II
C. Type III
D. Type IV
D. Type IV
542
From the following list, which test is most specific for RA?
A. Anti-dsDNA
B. Rheumatoid factor (RF)
C. Anticyclic citrullinated peptide (CCP)
D. Anti-SS-A/Ro
C. Anticyclic citrullinated peptide (CCP)
543
Which HIV marker is detectable within days of infection in patient serum?
A. Viral RNA
B. P24 antigen
C. IgM antibody
D. IgG antibody
A. Viral RNA
544
Which is the first antibody detected in serum after infection with hepatitis B?
A. Anti-HBe
B. Anti-HBc IgM
C. Anti-HBs
D. HBeAg
B. Anti-HBc IgM
545
In infectious mononucleosis, which of the following antibodies would be detected earliest during acute infection?
A. Anti-VCA IgM
B. Anti-EBNA
C. Heterophile antibodies
D. Anti-EA IgG
A. Anti-VCA IgM
546
Which of the following is a cause of a biological false-positive in the nontreponemal assays for syphilis?
A. Infectious mononucleosis
B. Rheumatoid arthritis
C. pregnancy
D. All of the above
D. All of the above
547
In which assay can a high concentration of antigen (analyte) cause hook effect?
A. EMIT
B. FPIA
C. Sandwich ELISA
D. TP-PA
C. Sandwich ELISA
548
Which type of immunoassay does NOT require a separation step?
A. Noncompetitive
B. Homogenous
C. Heterogenous
D. All of the above
B. Homogenous
