Unit 4 Flashcards
1
Q
Describe flow cytometry
A
-automated process that analyzes cells or beads in fluid suspensions for their light- scattering characteristics
-uses fluorochromes to identify cells by size, shape, and antigenic properties
- allows for rapid and accurate detection of cells found in small numbers
2
Q
What is immunophenotyping
A
Identifying their surface and cytoplasmic antigen expression
3
Q
What are fluorochcomes
A
Fluorescent molecule
4
Q
What do fluorochromes do?
A
-absorbs light across a spectrum of wavelengths and emits light of lower energy across a spectrum of longer wavelengths
5
Q
What is flow cytometry used to detect?
A
- leukemia
- lymphoma
- AIDS
- chronic granulomatous disease
- leukocyte adhesion deficiency
- fetal RBC
- F-cell identification in maternal blood
- identification of paroxysmal nocturnal hemoglobinuria
6
Q
What is flow cytometry used for?
A
- Enumerate hematopoietic stem cells
-detect human leukocyte antigen (HLA) antibodies in transplantation
-identify cells undergoing apoptosis
7
Q
What is a significant advantage of flow cytometry?
A
Because the flow rate of cells is so rapid, thousands of events can be analyzed in seconds, allowing for accurate detection of cells that are present in very small numbers
8
Q
What are the 4 parts of instrumentation of flow cytometry?
A
① fluidics
②laser light source
③optics and photodetectors
④ computer
9
Q
Describe fluidics of flow cytometry
A
- Allows for cell transport, one at a time
-each time a cell passes in front of a laser beam, light is scattered,and the interruption o laser signal is recorded
10
Q
Describe laser light source of flow cytometry
A
- For cell illumination and identification
-solid-state diode lasers are typically used
11
Q
Describe optics and photodetectors of flow cytometry
A
- Signal detection
12
Q
Describe computers of flow cytometry
A
- Data management
13
Q
What colors are lasers?
A
- Red
-blue
-violet
-ultraviolet (UV) - yellow-green
14
Q
What are the types of light scatter?
A
① forward scatter (FSC)
② side scatter (SSC)
15
Q
Describe forward scatter
A
-an indicator of size
16
Q
Describe side scatter
A
- indicative of granularity or the intracellular complexity of the cell
17
Q
What are the intrinsic parameters of the light sources of flow cytometry?
A
- forward scatter
- side scatter
*light scattering properties
18
Q
Describe extrinsic parameters in light source of flow cytometry
A
-require the addition of a fluorescent probe for their detection
19
Q
Describe principle of hydronomically focusing
In flow cytometry
A
- cells pass single file through the intersection of the laser light source
20
Q
What are the sample types common in flow cytometry?
A
- Whole blood
- bone marrow
- fluid aspirates
21
Q
What WBCs can be differentiated based solely on their intrinsic parameters?
A
- lymphocytes
- monocytes
- neutrophils
22
Q
What is flow cytometry steps?
A
① celli are processed into a suspension, and the cytometer draws up the cell suspension and injects the sample inside a carrier stream of isotonic saline (sheath fluid) to form a laminar flow
② The sample stream is constrained by the carrier stream and is thus hydrodynamically focused so that the cells pass in a single file through the intersection of the laser light source
③ each cell is interrogated by a light source that typically consists of one or more small air-cooled lasers
④ cells are labeled with a fluorochrome or Fluorescent molecules, that absorbs light across a
Spectrum of wavelengths and emits light of lower energy pattern of absorption (excitation) and emission
23
Q
What are common speciemens tested for
Flow cytometry?
A
Whole blood
Bone marrow
Fluid aspirates
24
Q
What is the additive in the tube that is used for whole blood collection?
A
EDTA
Heparin can also be used
25
What is required for a sample that has a lot of RBCs for flow cytometry?
Requires erythrocytes removal to allow for efficient analysis of WBC
26
Describe single-parameter histogram
- The y-axis consists of the number of events
- usually extrinsic parameters (fluorescent-labeled) antibody
- operator sets a marker to isolate the positive event!
-will calculate the percentage of positive events within the designated markers
27
Describe dual-parameter dot plot
- both parameters(axis) are chosen by operator
- the operator then draws a "gate" or isolates the population of interestfor further analysis
- gated cells are analyzed for fluorescence
- suppurated into four quadrants
28
Describe quadrant 1 of a dual parameter dot plot
X - axis → negative for Fluorescence
Y - axis → positive for Fluorescence
29
Describe quadrant 2 of dual parameter dot plot
X-axis → positive for fluorescence
Y- axis → positive for fluorescence
30
Describe quadrant 3 of dual-parameter dot plot
X-axis→ negative of fluorescence
Y-axis→ negative of fluorescence
31
Describe quadrant 4 of dual-parameter dot plot
X-axis → positive for Fluorescence
Y-axis→ negative for Fluorescence
32
What are some applications of flow cytometry?
① identifies particular markers for diagnosis and monitoring of leukemias and lymphomas
② enumerates peripheral blood. CD4+ T cells to classify stages of HIV disease and guide treatment
③ enumerates CD34+ cells in stem cells transplantation
④determines DNA content or ploidy status of tumor cells
⑤ helps diagnosis inherited diseases
33
What is the significance of the presence of CD5+?
Indication of mantle cell lymphoma (CLL)
34
How is the HIV stage classified)
Enumeration of peripheral blood CD4+ T cells by flow cytometry
35
What are the advantages of immunoassay automation?
- Reduces error
- is more accurate and precise
- requires fewer staff
- saves on controls, duplicates, dilutes, and repeats
- potential for better sample ID with use of bar coding
36
What are the two types of immunoassay analyzer?
- batch
- random-access analyzer
37
Describe batch analyzers
- Can examine multiple samples
- provide access to samples for formation of reaction mixture
- permits one type of analysis at a time
38
Describe random access analyzers
- Measure numerous analytes from multiple samples
- can perform different tests on any one sample
39
What are the tasks performed by automated analyzers?
- Introducing the sample
- adding reagents
- mixing reagents and sample
- incubating
- detecting reactions
- calculating
- reporting results
40
What does validation of immunoassay automation involve verification of?
- accuracy
- precision
- analytic sensitivity
- analytic specificity
- determination of interfering substances, reportable range, reference intervals
41
What is accuracy?
Tests ability to measure what it claims to measure
42
What is precision?
Ability to consistently reproduce a result on repeated testing of the same sample
43
What is analytic sensitivity?
The lowest measurable amount of an analyte
44
What is analytic specificity?
An assays ability to generate a negative result when the analyze is not present
45
What is a reportable range?
The range of values that will generate a positive result for the specimens assayed by the test procedure
46
What is reference interval?
Range of values found in healthy individuals
47
What is the single most important requirement for samples to be analyzed on a flow cytometer?
Cells must be in a single-call suspension
48
It an analyzer consistently indicates a positive test when the analyte in question is not present, this represents a problem with what?
Specificity
49
The various signals generated by cells intersecting with a flow cytometry laser are captured by what?
Photomultiplier tubes
50
If an analyzer gets different results each time the same sample is tested, what type of problem dues this represent?
Precision
51
What is flow cytometry most commonly used method?
Immunophenotyping of lymphoid and myloid
52
Describe hypersensitivity
- Exaggerated immune response to a typically harmless antigen
- results in tissue injury and disease
- 4 types
53
Describe the immediate reaction of hypersensitivity
- develop minutes to hours after antigen exposure
- type I,II, and III
54
Describe the delay reaction of hypersensitivity
- develop 24 to 48 hours after antigen exposure
-type IV
55
Describe type I hypersensitivity,
- cell bound antibodies react with antigen to release physiologically active substances
- complement is not involved
- known as "allergies"
56
Describe type II hypersensitivity
- Free antibody reacts with antigen associated with cell surfaces
- complement plays major role in producing tissue damage
57
Describe type III hypersensitivity
- Antibody reacts with soluble antigen to form complexes that precipitate in tissues
- complement plays major role in producing tissue damage
58
Describe type IV hypersensitivity
- not seen until 24-48 hours
- differs from the other three because sensitized T cells rather than antibody are responsible for symptoms
- complement not involved
59
What is another name for type I hypersensitivity?
Anaphylactic hypersensitivity
60
What is another name for type II hypersensitivity?
Antibody-mediated cytotoxic hypersensitivity
61
What is another name for type III hypersensitivity?
Complex-mediated hypersensitivity
62
What is another name for type IV hypersensitivity?
Cell-mediated hypersensitivity
63
What are the key components of type I hypersensitivity?
- IgE
- mast cells
- basophils
- eosinophils
64
Describe the sensitization phase of hypersensitivity
- APCs process allergens and present them to Th cells
- Th2 cells induce production of allergen-specific IgE
- IgE binds to FceRI receptors on most cells and basophils
65
Describe the activation phase of hypersensitivity I
- Allergen cross-links adjacent cell-bound IgEs
- mast cells and basophils degranulate
- chemical mediators are released and bind to target organs
- allergy symptoms produced
66
What are the type I preformed/primary mediators?
- Histamine
- heparin
- eosinophil chemomatic factor of anaphylaxis (ECF-A)
- neutrophil chemotactic factor
- proteases
67
What are the type I newly formed mediators?
- Platelet activating factor (PAF)
- prostaglandin (PG) D2
- Leukotrienes (LT) → B2, C4, D4 and E4
- cytokines
68
What are some common allergens?
- Pollen ''
- mold spores
- animal danders
- dust mites
- insect venom
- certain foods
- certain dogs
- latex
69
What are the clinical manifestations of type I?
- Rhinitis (hay fever)
- allergic asthma
- food allergies
- urticaria (hives) → wheal and flare
- eczema
-systemic anaphylaxis → potentially fatal
70
What are treatments for type I?
- Avoid allergens '
- drug therapy → antihistamines, bronchodilators, most cell stabilizers, corticosteroids epinephrine
- monoclonal anti-lgE antibody
- allergy immunotherapy (AIT)→administer gradually, increasing doses of allergen
71
What are the in vivo skin tests of type I?
-percutaneous or intradermal
72
Describe process of percutaneous and intradermal of type I
① apply a panel of allergens to separate sites on the skin
② wait 15 to 20 minutes
* positive test = wheal and flare at the site of application
73
Describe allergen specific IgE testing of type I?
- RAST (radioallergosorbent test) was the first type of test to be used for specific IgE
-enzyme methods are now used to detect IgEt specific allergen in patient serum
-safer than skin testing
74
What are the in vitro tests of type I?
- Allergen-specific IgE testing
- total IgE
75
Describe the total IgE test of type I
-RIST (radioimmunosorbent test) was first type of test method for total IgE
-enzymes are now use to detect total concentration of IgE in patient serum
76
What are allergens?
Antigens that trigger type I
77
What is passive cutaneous anaphylaxis?
Redness and swelling at site that was injected with serum (from patient who is allergic to allergen) and later exposed to allergen
78
What is atopy?
- refers to an inherited tendency to develop classic allergic responses to naturally occurring inhaled or ingested allergens
79
How long does it take for type I to occur?
30-60 minutes
80
What regulates IgE production ?
Th2 cells
81
What is predominant in people with allergies? What does this cause to be produce?
-Th2
- IL-4 and IL-13
82
What are IL-4 and IL-13 responsible for?
- Final differentiation that occurs in B cells, initiating the transcription of the genes that codes for the epsilon heavy chain of immunoglobulin molecules belonging to the IgE
83
Describe allergic rhinitis
- Most common form of atopy
- hay fever
84
What are symptoms of Hay Feveri?
- paroxysmal sneering
- rhinorrhea (runny nose)
- nasal congestion
- itchy eyes and nose
85
What is angioedema?
Skin reactions that occur deeper in the skin
86
What can hives and hay fever be treated with?
Decongestants and antihistamines
87
What is used to treat severe asthma?
Anti-lgE monoclonal antibodies
88
Describe allergy immunotherapy (AIT)
- Goal is to induce immune tolerance to a specific allergen by administering gradually increasing doses of the allergen over time
89
How is the allergic reaction scored?
-based on presence or absence of erythema
-diameter of the wheal
90
What has largely replaced RIST?
- Noncompetive solid-phase immunoassays
- nephelometry assays
91
When is total serum IgE testing most beneficial?
In evaluating patients with other conditions in which IgE levels may be elevated
92
What are the key components of type II?
- IgG and IgM directed against cell surface antigen
- complement
93
What effects can type II have on antibodies?
- Cell destruction
- inhibition of cell function
- increase in cell function
94
What can cause cell damage for type II?
- Activation of classical pathway of complement and cell lysis
- opsinozation and phagocytosis of the cell
- antibody
- antibody-dependent cell-mediated cytotoxicity (ADCC)
95
What are clinical examples of type II?
- transfusion reactions
- hemolytic disease of the newborn (HDN)
- autoimmune hemolytic anemia
- anti-GBM disease
- hashimotos disease
96
How long dues it take type II to occur?
A few hours after exposare antigen
97
What is a isohemagglutinin?
When anti-a and anti-B antibodies are naturally occurring antibodies which are probably triggered by contact with similar antigenic determinants
98
What happens when sensitized mast cells and basophils become activated?
Release chemicals that induce symptoms
99
Describe mast cells of the sensitization phase of type I?
-have abundant cytoplasmic granules that store numerous preformed inflammatory mediators
100
Describe binding of IgE to mast cells or basophils
- increase half life from 2-3 days to 10 days atleast
Once IgE binds, functions as an antigen receptor on mast cells and basophils
101
What are the effector calls of type I?
Mast cells
102
Describe hemolytic disease of the newborn (HDN)
-pregnant woman produces antibodies to Rh antigens (usually RhD) on fetal RBCs
- IgG cross placenta and and destroy fetal RBCs
103
Describe autoimmune hemolytic anemia
- type II reaction
- directed against self-antigens because this disease forms antibodies to their own RBCs
-2 kinds of antibodies → warm reactive antibodies and cold agglutinins
104
What are the symptoms of autoimmune hemolytic anemia?
- Malaise '
- lightheadedness
- weakness
- unexplained fever
- pallor
- mild jaundice
105
What temperature does warm reactive antibodies react at?
37°C
106
What temperature does cold agglutinins react to?
Below 30°C
107
Describe the warm autoimmune hemolytic anemia
- account for more than 70% of autoimmune anemias
- characterized by formation of IgG antibody
108
Describe cold agglutinins
- autoantibodies that cause RBCs to clump together at cold temperatures
- below 37°C
- belong to IgM class
109
What are the harmful effects of cold agglutinins that are active in vitro up to temperatures of 30°C or more?
- Blocking of small vessels on exposure to cold
- RBC agglutination
- production of hemolytic anemia
110
Describe chronic cold agglutinin syndrome
- Usually has a gradual onset and chronic course
- usually seen in elderly
-agglutinins usually contain monoclonal kappa light chains
- condition may also be due to presence of lymphoma in some individuals
111
Describe postinfection cold agglutinin syndrome
- Commonly follows infection with mycoplasma pneumoniae or infectious mononucleosis
112
What is found in those affected with cold agglutinin syndrome?
- high titer of cold agglutinins
- large amounts of C3d resulting in a positive direct antiglobulintest
113
What are high-titer monoclonal cold agglutinins associated with?
- B-cell CLL
- B cell lymphoma s
- Hodgkin disease
- Waldenstrom macroglobulinemia
- SLE
- cold agglutinin syndrome
114
Describe paroxysmal cold hemoglobinuria
- Can cause autoimmune hemolytic anemia
- occurs after certain infections (measels, mumps, chickenpox, and infections mononucleosis)
- agglutinate at cold temperatures
- activates complement at 37°c to produce intermittent hemolysis.
115
Describe mycoplasma pneumoniae
- Cold agglutinins found in approximately 55% of patients
- cold agglutinius appear around week 2 or 3 after onset
-reoccurring respiratory infections
116
What are the symptoms of mycoplasma pneumoniae?
- increasing pallor
- jaundice
- enlarged spleen (splenomegaly)
- hemoglobinogluria
- if hemolytic anemia occurs, proceeds at alarming rate and may be fatal
117
Describe infectious mononucleosis
- 50% of patients with disease have anti-i present
- antibody normally detectable in vitro up to a temperature of about 25°C
118
Describe direct antiglobulin test (DAT)
- detects RBCs coated with complement components or IgG antibody in vivo
- patient RBCs are incubated with a poly-specific anti human Ig directed against IgG and C’
- if positive (agglutination), the test is repeated with mono-specific anti-IgG, anti-C3b, and anti-C3d
119
Describe indirect antiglobulin test (IAT)
- Coombs test
- test patient serum for antibodies to RBC antigens
- positive test → agglutination
120
Describe the process of indirect antiglobuun test
① incubate reagent RBCs with patient serum at 37°C, wash to remove excess
② add anti-human globulin
121
What is DAT used to detect?
- Transfusion reactions
- HDFN
- autoimmune hemolytic anemia
- drug induced hemolytic anemia
- detects in vivo binding
122
What is IAT used for?
- Cross matching of blood to prevent a transfusion reaction
- determine the presence of a particular antibody in patient plasma
- type patient RBCs for specific blood group antigens
- detects in vitro binding
123
Describe type III hypersensitivity
- keys components are IgG and IgM directed against a soluble antigen
- small antigen-antibody complexes precipitate out and deposit in tissues
- C’ binds → vasodilation and vasopermeability increase
- macrophages and neutrophils migrate to affected areas and release lysosomal enzymes, resulting in tissue damage
124
How long does type III take to occur!
A few hours after exposure
125
Describe Arthus reaction
- Skin reaction caused by type III hypersensitivity
- localized inflammation characterized by redness and edema
- peaks at 3 to 8 hours
126
Describe serum sickness
- Generalized type III hypersensitivity reaction
- caused by passive immunization of humans with animal serum
- produces antibodies against the foreign animal proteins in patients
- causes immune complexes to form and deposit in tissues
127
What are the symptoms of Serum sickness?
- headache
- fever
- nausea
- joint pain
- rashes
- lymphadenopathy
128
What are other conditions (besides Arthus and serum sickness) associated with type III?
- SLE
- RA
- reactions to bee sting
- Drug reactions (penicillin)
-sequelae to infection (post streptococcal glomerulonephiritis)
129
What are the laboratory tests of type III?
- Testing ANAs
- fluorescent staining of tissue sections to detect deposited immune complexes
- testing for rheumatoid factor (anti-IgG)
- testing complement levels
130
When are complement levels decreased in serum?
- During periods of nigh disease activity
131
When do symptoms of a type IV reaction peak?
48-72 hours after exposure
132
What methods detect antinuclear antibodies in SLE and RA?
- indirect immunofluorescence
- ELISA
- fluorescent microsphere multiplex immunoassay
133
What methods can detect RF?
- Latex agglutination
- nephelometry
- other immunoassays
134
Describe Type IV hypersensitivity
- Th1 and macrophages are involved
- APCs present antigen to naive T helper cells, which differentiate into Th1 cells
- Th1 cells release cytokines that attract and activate macrophages
- macrophages induce inflammation
- cytotoxic t lymphocytes are recruited and destroyed target cells
135
What are triggers of type IV ?
- Mycobacterium tuberculosis '
- myobacterium leprae
- pneumocystis carinil
- leishmania species
- herpes simplexvirus
(intracellular pathogens)
- contact dermatitis
- hypersensitivity pneumonitis
136
Describe hypersensitivity pneumonitis
- Allergic diseases of lungs
- caused by inhalation of bacterial and fungal spores
- primarily mediated by sensitized T cells that respond to inhaled allergens
-
137
What are some examples of hypersensitivity pneumonitis
- Farmers lung disease
- birds breeders lung disease
- humidifier lung disease
138
Describe contact dermatitis
- Low-molecular weight compounds contact the skin and act as haptens to sensitive Th1 cells
139
What are triggers of contact dermatitis?
- Poison ivy '
- poison oak
- Nickle salts
- cosmetics
- hair dyes
- latex
140
What are the symptoms of contact dermatitis?
- Skin eruptions
- erythema -
- Swelling
- papules
141
What are granoulomas?
- Cluster of cells produced by chronic persistence of antigen
- can function to wall off the organism in contained area, preventing spread.
142
What are the skin tests for type IV?
- Patch test
- skin testing for immunodeficiency (inject common antigens intradermally)
- mantoux method
143
Describe the patch test
- Antigen applied to skin surface
- test for contact dermatitis
- positive test → redness with papules or blisters
144
Describe mantoux method
- Antigen injected intradermally
- test for tuberculosis exposure (PPD) or T cell function)
- positive test→ induration
145
What are types of interferon gamma release assays
- Quantiferon TB gold plus assay
- T- spot-TB test
146
Describe interferon gramma release assays (IGRA)
- Measures production of IFN- gamma by patient T cells stimulated with MTB antigens
147
Describe T-SPOT-TB test
- Patient mononuclear cells are incubated with MTB antigens and tested for IFN- gamma by ELISPOT
148
What is the gold standard testing for contact dermatitis?
Patch test
149
What could a positive result in DAT show?
- Presence of IgG on RBCs
- presence of C3b or C3d on RBCs
- A transfusion reaction caused by preformed antibody
150
What is the best test to perform if an allergy to ryegrass is expected:
Skin prick test
151
What is the immune phenomenon associated with the Arthus reaction?
Deposition of immune complexes in blood vessels
152
What conclusion should be drawn about a patient whose total IgE level was determined to be 150 IU/mL?
Antigen- specific testing should be done
153
What is the difference between type I and type II?
Type II involves cellular antigens
154
A young woman developed red, itchy papules on her wrist 2 days after wearing a new bracelet. What is this reaction caused by?
An inflammatory response induced by cytokines released from Th1
155
What are reactions to latex caused by?
- type I
- type IV
- skin irritation
156
How is the cold agglutinin titer determined?
- Patient serum should be seperated from whole blood at 37°C and tested at 4°C
157
What is the principle of the tuberculin test
- PPD is injected into the forearm and stimulates a delayed type hypersensitivity response mediated by T cells.in patients with prior exposure causes induration at the injection site within 48-72 hours
158
Describe auto immune diseases
- humoral and cell-mediated immune responses directed toward self-antigens
- cause tissue or organ damage
- systemic or organ-specific
.due to loss of self tolerance
159
What is self tolerance
Ability of the immune system to accept self-antigens and not initiate an immune response against them
160
Describe mechanisms of central and peripheral tolerance
- during maturation process of T cells, the great majority of undifferentiated lymphocytes that are processed through the thymus do not survive
- The process is not totally effective, however, as normal individuals do possess self-reactive lymphocytes
161
What does autoimmunity result from?
- Complex interactions between genetic and environmental factors
- inheritance of certain genes can make some individuals more susceptible
- hormones can influence autoimmunity (women are three times as likely to acquire an autoimmune disease)
- tissue injury
- microbial infections
- environmental factor that can alter gene expression
162
What are microbial infections that can trigger autoimmunity?
- Molecular Mimicry
- epitope spreading
- superantigens
163
Why does molecular mimicry trigger autoimmunity?
Bacteria or viruses possess antigens that are like a self antigen
164
Why does epitope spreading trigger autoimmunity?
-immune response to a microbe expands to activate immune response to other antigens, including self antigens
165
Why do superantigens trigger autoimmunity?
Can activate numerous clones of T cells, or through certain viruses, which can cause polyclonal B cells activation
166
What are systemic diseases of autoimmunity?
- SLE, RA, and other SARDs, GPA
167
What are organ specific diseases of autoimmunity?
- Autoimmune thyroid disease
- type I diabetes
- celiac disease
- autoimmune liver diseases
- multiple sclerosis
- myasthenia gravis
- anti-glomerular basement membrane disease
168
Describe immunologic tolerance
A state or immune unresponsiveness that is directed against a specific antigen
169
Describe central tolerance
Occurs in central or primary lymphoid organs, thymus, and bone marrow
170
What is anergy?
Absence of the normal immune response to a particular antigen or allergen
171
Describe peripheral tolerance
Lymphocytes that recognize self-antigens in the secondary lymphoid organs are rendered incapable of reacting with those antigens
172
What are the classifications of autoimmune diseases?
① systemic
② organ specific
173
What are the a groups of systemic diseases?
- Systemic autoimmune rheumatic diseases (SARDs)
- anti-neutrophil cytoplasmic antibodies ( ANCAs)
174
Describe SARDs
-involve inflammation of the joints and their associated structures
175
Describe ANCAs
Characterized by inflammation of the blood vessel
176
Describe systemic lupus erythematosus (SLE)
- Chronic systemic inflammatory disease that affects multiple organ systems
- pathology caused by type III, tissue damage occurs at the sites in the body where immune complexes have deposited
- develop numerous autoantibodies
177
What happens when immune complexes form within a patient with SLE?
Trigger
- complement activation
- chemotaxis of neutrophils
- inflammation
178
What autoantibodies develop in patients with SLE?
- dsDNA and other nuclear components
- lymphocytes
- RBCs
- platelets
179
What are symptoms of SLE?
- Fatigue
- malaise
- weight loss
- Joint involvement (most frequently reported-90%)
- skin rashes (80%)
- renal involvement (50%)
- neurological symptoms
- anemia, leukopenia, thrombocytopenia
180
Describe the skin rash that occurs on patients with SLE
- A classic butterfly rash across the nose and cheeks
-this is where lupus comes from, meaning wolf-like
181
What was the first clue in the mystery of lupus?
Discovery of LE cell
182
Who discovered LE cells?
Malcolm Hargraves (1948)
183
Describe the LE cell
- It is a neutrophil that have engulfed the antibody- coated nucleus of another neutrophil, mainly in vitro
184
What was the second discovery of SLE?
- It is associated with more than 25 autoantibodies
- this reflects a generalized dysregulation of the immune system in SLE
185
What are the laboratory tests to diagnose SLE?
- CBC
- urinalysis
- CRP/ESR (elevated during flare-ups)
- complement quantitation (C3 levels can be decreased during inflammation)
- ANAs
186
What test is typically done first if SLE is suspected?
- Screening test for antinuclear antibodies (ANAs)
187
What treatment is recommended for all SLE patients?
Anti-malarial drug→hydroxychloroquine
188
What is the most common cause of death In lupus?
Renal failure and infection
189
Describe ANAs
- Directed against antigens in cell nuclei
- present in move than 95% of lupus patients
- heterogenous group of antibodies '
- includes:
-anti-dsDNA (lupus specific)
-anti-ssDNA
-anti-histones and nucleosomes
-antibodies to centromere or nuclear components
-anti-ENA (anti-sm, anti-RNP, anti-ss-A, and anti-ss-B)
190
What antibody (ANA) is most specific for SLE?
- dsDNA
- especially found in combination with low levels of complement component C3
191
What anti-histories are detected in almost all patients with drug-induced lupus?
H2A and H2B
192
What is a nucleolus?
Prominent structure within the nucleus where transcription and processing of ribosomal RNA and assembly of ribosomes takes place
193
What are methods usedto detect ANAs in patient serum?
- Indirect immunofluorescence (IIF)
- ELISA
- microsphere multiplex immunoassay (MIA)
- immunodiffusion
194
What is the dsDNA immune fluorescent pattern?
Homogenous on IIF
195
What is the immunofluorescent pattern of anti-histones?
Homogenous in IIF assay
196
What is the immunofluorescent pattern of nucleosome antibodies?
Homogenous in IIF assay
197
What are the immunofluorescent patterns of anti-sm and anti-RNP?
Coarse speckled
198
What testing is most widely used to detect ANAs?
Fluorescent antinuclear antibody
199
What is the FANA test principle?
① incubate patient serum with hep-2 cells fixed onto microscope side
② wash and incubate with fluorescein- labeled anti-human IgG
③ wash and view under-fluorescent microscope
200
Describe immunofluorence using crithidia luciliae
- An IIF using C. Luciliae as substrate
- contains circular organelle called a kinetoplast (rich in dsDNA)
- used to detect antibodies to dsDNA antibody titers
201
Describe ENA Ouchterlony test
- Immunodiffusion test detects antibodies to specific ENA
- patient serum in outer wells react with ENA antigens in center well
- in this example, patient A has antibody to Sm
- anti-sm is diagnostic for SLE
- positive reactions indicated by immunoprecipitation lines of serologicalidentity
- not as sensitive
- long turnaround times
202
Describe ELISA testing of SLE
- Has come into wider use for detection of: anti-dsDNA, antihistone antibodies, anti-ss A, and anti-ss-B
- quantitative
- less subjective
203
Describe phospholipid antibodies found in SLE patients
- Heterogenous group of antibodies that bird to phospholipids
- Found in about 60% of lupus patients
- associated with deep vein and arterial thrombosis
- increased risk of reoccurring pregnancy loss
- can cause false positive results in nontreponemal tests for syphilis
204
What is an example of a phospholipid antibody?
The lupus anticoagulant → produces prolonged APTT and PT
205
What are the three main applications of IIF?
① as initial test to determine the presence or absence of ANAs in patients with SARDs, aiding in diagnosis
② to provide guidance in selection of follow-up tests based on the immunofluorescence patterns obtained
③ to determine ANA titer because moderate to high titers have been better correlated with disease
206
Why are HEp-2 cells used in IIF?
-they have large nuclei with high antigen expression, allowing for high sensitivity and facilitating visualization of results
207
What are the 4 major nuclear pattern groups?
① homogenous
② speckled
③ centromere
④ nucleolar
208
Describe homogenous nuclear pattern
- Characterized by uniform staining of entire nucleus in interphase cells and of condensed chromosomal region in metaphase cells
- associated with dsDNA, histones, and nucleosomes
209
When is homogenous nuclear patterns presents?
Found in patients with:
- SLE
- drug induced lupus
- chronic autoimmune hepatitis (AIH)
- juvenile idiopathic arthritis
210
Describe the speckled nuclear pattern
- Characterized by discrete fluorescent specks throughout the nuclei of interphase cells
- 3 groups: dense fine, tiny/fine, and large/course
211
What are fine or coarse speckles associated with?
- Antibodies to ENAs '
-SLE
-Sjogren’s syndrome
-SSc
- other SARDs
212
What are the dense fine speckles associated with?
- Antibodies to the DFS70/LEDGF antigen
- correlated with absence of a SARD upon confirmatory test
213
Describe the centromere nuclear pattern
- Numerous discrete speckles are seen in nuclei of interphase cells and the chromatin of dividing cells
- 46 speckles, represents each chromosome
- found mainly in patients with CREST syndrome
214
Describe the nucleolar nuclear pattern
- Prominent staining of the nucleoli within nuclei of interphase cells is seen in this pattern
- seen in patients with SSc but also can be present in other SARDs
215
Describe rheumatoid arthritis (RA)
- Chronic arthritis of the peripheral joints that can progress to joint deformity and disability
- 25% of patients have osteoporosis
- some patients also develop:
-subcutaneous nodules
-pericarditis
-interstitial lung disease
-vasculitis
216
Describe pathology of RA
- Inflammation destroys the bone and cartilage
- TNF-alpha plays key role in the process
- overly active osteoclasts absorb the bone
- autoantibodies combine with antigens to form immune complexes
217
Describe treatments for RA
- NSAIDS
- disease-modifying anti-rheumatic drugs (DMARDs)
- biological agent that target TNF-alpha
218
What are some laboratory tests for RA?
- Rheumatoid factor
- anti-CCP
- ANAs
- ESRs, CRP, and C’
219
Describe rheumatoid factor
-autoantibody (usually IgM) that reacts with Fc portion of IgG
-found in approximately 80% of patients with RA, not specific for RA
220
Describe anti-CCP
- autoantibody directed against cyclic citrullinated peptide (containing modified Arginine)
- highly specific RA
- best for early detection of RA
221
What is pannus?
A sheet of inflammatory granulation tissue that grows into the joint space and invades the cartilage
222
What are the cytokines found in synovial fluid that contribute to inflammation?
- IL-1
- IL-6
- IL-17
- TNF-alpha→ key role in stimulating cytokine production and facilitate transport of WBC to affected area
223
What is the gold standard for ANA testing?
IIF
224
What are the symptoms of rheumatoid arthritis?
-malaise ''
- fatigue
- fever
- weight loss
- transient joint pain in hands and feet
- muscle spasm
- limitation of movement
225
What autoimmune disease is characterized by dry mouth and eyes?
Sjögren’s syndrome
226
What is the most common cause of death in RA?
Cardiovascular disease
227
What are the criteria for identification of RA?
- number and Type of joints involved
- duration of symptoms
- serology results for RF and anti-CCP
- serum level of the acute phase reactant
- CRP
-ESR
228
What are the components of RF?
Patients with RA and specific HLA-DRB1 alleles or PTPN22 gene polymorphism
229
What are other systemic autoimmune rheumatic diseases (SARDs)?
- Sjorgren syndrome
- Systemic sclerosis (SSc)
- mixed connective tissue disease
- inflammatory myopathies
230
Describe sjogren syndrome
- Dry eyes and mouth
- ss-A and ss-B antibodies
- characterized by chronic inflammation of the exocrine glands, most notably → the ocular and salivary gland
- have primary (solo) and secondary (other diseases) categories
231
Describe systemic sclerosis (SSc)
- Fibrosis and vasculitis affecting skin, joints, other organs
- includes CREST syndrome and many ANAs
232
What are the symptoms of systemic sclerosis?
- tightening and hardening of skin
- musculoskeletal pain
- raynaud's phenomenon
- heartburn
233
Describe mixed connective tissue disease
- Overlap of limited cutaneous SSc and other SARDs; anti-u1-RNP
234
Describe inflammatory myopathies
- Polymyositis and dermatomyostis
- progressive muscle weakness; many ANAs
- characterized by chronic inflammation of the skeletal muscles and progressive muscle weakness
235
Describe granulomatosis with polyangitis
- Wegners granulomatosis
- rare autoimmune disease involving inflammation of small-to-medium sized blood vessels and respiratory tract
- progresses to more systemic disease involving other organs (kidneys, joints, skin)
- most patients have antibodies to neutrophil cytoplasmic antigens such as proteinase 3
- neutrophil activation results in damage to vascular endothelium and Th1 response
236
What are symptoms of granulomatosis with polyangitis? (GPA)
- Fever
- malaise
- joint pain
- anorexia
- weight loss
- persistent runny nose
- rhinitis
- sinusitis
- oral or nasal ulcers
- gingivitis
- hearing loss
- collapsed nose bridge
- renal involvement
- pain and arthritis of large joints
- skin lesions
237
What alleles are associated with GPA?
- HLA-DRB1*0401 (Caucasian)
- HLA-DRB1*0901 (Asian and African American)
- HLA-DRB*1501 (Asian and African American)
238
What is the treatment for GPA?
- combo of glucocorticoid drugs and cyclophosphamide ( severe forms)
- monoclonal antibody rituximab
-immune suppressive therapy
239
Describe anti-neutrophil cytoplasmic antibodies (ANCA)
- Produced against proteins in neutrophil granules
- strongly associated with syndromes involving vascular inflammation
- detected by IIF on ethanol-fixed leukocytes
- ELISA and chemo luminescent assays are also available
240
Describe ANCA detected by IIF on ethanol fixed leukocytes procedure
① patient serum incubated with microscope slide containing ethanol- fixed leukocytes
② wash and add FITC- labeled anti-lgG conjugate
③ Wash and view fluorescence in neutrophils under fluorescent microscope
241
What are the 3 syndromes involving vascular inflammation associated with ANCAs?
- GPA
-microscopic polyangitis (MPA)
- eosinophilic granulomatosis with polyangitis ( EGPA)
242
What are the two patterns that can be observed with ANCAs?
- cytoplasmic (c-ANCA)
- pernicular (p- ANCA)
243
Describe c-ANCA pattern
- primarily caused by PR3-ANCA and appears as a diffuse, granular staining in cytoplasm of neutrophils
244
Describe p-ANCA pattern
-fluorescence surrounds the lobes of the nucleus, blending them together so that individual lobes cannot be distinguished
245
What is the autoantigen of c-ANCA?
PR3 antigen
246
What disease is associated with c-ANCA?
- GPA
247
What is the autoantigen of p-ANCA?
Positively charged antigens, including myeloperoxidase (MPO)
248
What are diseases associated with p-ANCA?
- MPA
- EGPA
249
What test should be run if the initial IIF test results are positive for ANCA?
Confirmed by PR3- and MPO-specific immanoassays
250
What diseases can ANCA be detected in?
- SARDs, such as SLE and RA '
- autoimmune gastrointestinal disease
- liver disease
- HIV
- hepatitis C
-malignancy
251
Describe autoimmune thyroid diseases (AITDs)
- thyroid hormone synthesis is carefully regulated by endocrine feedback loop
- autoantibodies produced in AITDs can lead to decreased or increased production of thyroid hormones
252
What diseases are AITDs?
- Hashimotos thyroiditis
- graves disease
253
What is the target tissue of graves disease and hashimotos disease?
Thyroid grand
254
Describe hashimotos thyroïditis
- immune destruction of the thyroid gland produces hypothyroidism
- lab results:
-normal or high TSH
-low free T4
-anti-TPO
- anti-Tg
255
What are hashímotos thyroiditis symptoms?
- fatigue
- dry skin
- weight gain
- brittle hair
-formation of goiter
256
What is hypothyroidism?
Decreased thyroid function
257
What are symptoms of hypothyroidism?
-dry skin
- decreased sweating
- puffy face with edematous eyelids
- pallor with a yellow tinge
- weight gain
- fatigue
- brittle hair
258
Describe Graves’ disease
- AITD characterized by hyperthyroidism
- TRAbs produced
- low TSH and high FT4; antibodies to TPO and Tg may be produced
259
What are autoantibodies of Hashimoto’s thyroiditis?
- Anti-thyroglobulin
- anti-thyroid peroxides
260
What are the autoantibodies of Graves’ disease?
-thyroid-stimulating hormone receptor antibodies (TRAbs)
-anti-thyroglobulin
- anti-thyroid peroxides (TPO)
261
What is hyperthyroidism?
- State of excess thyroid function
- associated with Graves’ disease
262
What are symptoms of Graves’ disease?
- nervousness
- insomnia
- depression
- weight loss
- heat intolerance
- sweating
- rapid heartbeat
- palpitations
- breathlessness
- fatigue
- cardiac dysrhythmias
- bulging eyes
- restlessness
- lower leg edema
263
What are treatments for hashimotos thyroïditis?
-daily oral thyroid hormone replacement therapy, levothyroxine (T4)
264
What are the treatments for Graves’ disease?
- Radio active iodine
265
What are most commonly used to detect thyroid antibodies?
- Sensitive ELISA
- chemiluminescent immunoassays
266
What is the best indicator for hashimotos thyroiditis?
Antibodies to TPO
267
What is highly indicative of Graves’ disease?
TRAbs
268
What are the two types of tests for TRAbs?
- Binding assay
- bioassay
269
Describe binding assays for TRAbs
- Automated solid-phase ELISA
- chemoluminescent immunoassays
- labeled TRAbs reagent competes with the patient antibody for TSH receptor bound to solid phase
- unable to distinguish between TSI and TRAbs
270
Describe bioassay for TRAbs
- Require tissue culture
- difficult to perform
- specifically measure the function of TSI
271
Describe type I diabetes mellitus (T1D)
- Endocrine disorder characterized by hyperglycemia
- type I destruction of beta cells in pancreas results in insulin deficiency
- genetic susceptibility to the disease
272
What are the long term effects of type I diabetes mellitus?
- Cardiovascular disease
- kidney dysfunction
- nerve damage
- blindness
- infections
273
What would the results look like for a patient with type I diabetes mellitus?
- increased glucose blood level
- elevated HbA1c
- autoantibodies to GAD and IA-2, ICA
274
What is hyperglycemia?
A high level of glucose in the blood
275
What are the four types of diabetes?
-type I
- type II
- gestational
- for other reasons (neonatal, Pancreatitis)
276
What is the treatment for type I diabetes mellitus
- lifelong insulin injections to control glucose levels
277
What genes are usually carried by patients with type I diabetes mellitus?
- HLA-DR3
- DR4
- increased risk if both are present
278
What leads to fibrosis and destruction of most beta cells in patients with type I diabetes mellitus?
- Progressive inflammation of the islets of langerhans in pancreas
279
What are the four criteria that is used to diagnose type I diabetes mellitus?
*only one is required
① fasting glucose greater than 126 mg/dL on more than one occasion
② a random plasma glucose level of 200 mg/dL or more with classic symptoms of diabetes
③oral glucose tolerance test of 200 mg/dL or more in a 2-hour samplewith a 75 g glucose load
④ a hemoglobin A1c value (HbA1c) greater than 6.5%
280
Describe celiac disease
- Affects small intestine and other organs
- triggered by gluten
281
What are the symptoms of celiac disease?
- Diarrhea
- abdominal pain
- bloating
282
What is the treatment for celiacs disease?
Gluten-free diet
283
In celiacs disease, autoantibodies form in HLA-DQ2 or HLA-DQ8 positive people to what?
- gliadin (component of gluten)
- tissue transglutaminase (IgA is screening test of choice)
-endomysium (EMA)
284
What environmental factors are believed to play a role in development of celiac disease?
- gluten administered at 4 months or younger in absence of breast feeding
-rotavirus infection
-overgrowth of pathogenic bacteria in the gut
285
What is the diagnosis of celiac disease based in?
- clinical symptoms
- serological test findings
- duodenal biopsy
- presence of HLA-DQ2 or HLA-DQ8 haplotype
286
Describe autoimmune liver diseases
- Immune-mediated liver diseasesthat can lead to end-stage liverfailure if left untreated
- includes:
-autoimmune hepatitis (AIH)
-primary biliary cholangitis (PBC)
287
Describe autoimmune hepatitis
- hepatocytes targeted
- AIH-1- positive for SMA, ANAs
- AIH-2- positive for LKM-1 or LC-1 antibodies
- affects small interlobular bile ducts
288
What are symptoms of AIH?
-25% are asymptomatic
- fatigue
- nauseous
- weight loss
- abdominal pain
- itching
- maculopopular rashes
- jaundice
289
What alleles are associated with AIH-1?
HLA-DR-3 and HLA-DR4
290
What alleles are associated with AIH-2?
- HLA-DRB1 and HLA-DQB1
291
What would lab results look like of a patient with AIH?
- Elevated levels of the liver enzymes asparate aminotransferase (AST) and alanine aminotransferase (ALT)
-increase in serum bilirubin and alkaline phosphate
- IgG are high
292
What is necessary to confirm AIH?
Liver biopsy
293
What is the treatment for AIH?
- immunosuppressant treatment of prednisolone
- arathioprine to maintain remission
294
Describe PBC
- Destruction of intrahepatic bile ducts; cholestasis
- inflammation of portal vein in liver
- accumulation of scar tissue that can lead to cirrhosis and liver failure
- majority of patients produce mitochondrial Abs (AMAs)
295
What is the most common autoimmune liver disease?
PBC
296
What is cholestasis
A condition in whichthe flow of bile is slowed or blocked
297
What are the symptoms of PBC?
- Some can be asymptomatic
- fatigue
- itchy skin (pruritis)
- abdominal pain
- dry eyes
- dry mouth
- jaundice
- greasy stools
298
What is the standard initial therapy of PBC?
-ursodeoxycholic acid (UDCA) → bile acid that helps move bile through the liver
299
What are the 3 criteria of PBC diagnosing?
- AMAs present
- serum alkaline phosphates level elevated at least 1.5 times the upper limit of normal for 6 months
- liver biopsy showing nonsuppurative destruction cholangitis andinterlobular bile duct injury
* 2out of 3 needed
300
What methods are there to detect AMAs?
-IIF
- immunoblotting with mitochondrial preparations from mammal tissues
- ELISA
- fluorescent microbead immunoassay
301
Describe multiple sclerosis (MS)
- Involves inflammation and destruction of the central nervous system.
- most patients produce antibodies against myelin basic protein
- plaques form in while matter of the brain and spinal Cord, causing destruction of the myelin sheath of axons
302
What are the symptoms of multiple sclerosis?
- Visual disturbances
- weakness in limps
- dizziness
- sensory abnormalities ( pins and needles tingling)
- facial palsy
303
What would be the laboratory findings of a patient with multiple sclerosis?
-lesions on magnetic resonance imaging (MRI)
-increased immunoglobulins in spinal fluid and increased IgG index
-oligocional bands on protein electrophoresis of CSF
304
What gene is closely associated with inheritance of MS
DRB1*1501
305
What are environmental factors that have been associated with MS?
- Reduced exposure to sunlight
- vitamin D deficiency
- cigarette smoking
- infection with EBV after early childhood
306
What is the treatment of MS?
- Glucocorticoids
- disease modifying therapy
307
Describe myasthenia gravis
- Affects neuromuscular junction, resulting in weak skeletal muscles
- most patients have antibodies to acetylcholine receptors (ACHR) which block binding of ACH to receptor and transmission of nerve impulses that activate muscles
- heterogenous
308
What are symptoms of myasthenia Gravis?
- Drooping eyelids
- inability to retract corners of mouth
- Difficulty speaking, chewing,and swallowing
- inability to support think, neck or head
- respiratory muscle weakness
- associated with several HLA antigen abnormalities
309
What is the main contributor to pathogenosis of MG?
- Antibody to ACH receptors
- 80-85% patients have antibody
310
What other diseases are associated with presence of MG?
- SLE
- RA
- pernicious anemia
- thyroïditis
311
Describe laboratory testing for MG
- RIA is used to detect antibody, based on assays that block the binding of receptors by anti-ACH receptor (ACHR) antibody
- radio labeled snake venom called alpha-bungarotoxin is used to irreversibly bind to ACHRs
- precipitation of receptors caused by combination with antibody is then measured
- a quick immunostick ELISA has also been developed for testing
312
What is the treatment for MG?
- Anti-cholinsterase agents to prevent destruction of neurotransmitter Ah
-thymectomy
-high doses of glucocorticoid drugs
- immunosuppressive drugs
313
What is the gold standard for detecting binding AChRs?
Quantitative radioimmunoassay that have radio-labeledsnake venous
314
In MG, if the patient tests negative for AChRs, what should be tested for?
-MuSK antibodies
-this can be done by quantitative RIA
315
Describe anti-glomerular basement membrane disease
- formerly known as good pasture syndrome
- patients produce autoantibodies to basement membranes living the renal glomeruli and lung alveoli
- immune complexes bind to basement membranes, attract complement, and cause damage by type II hypersensitivity
- antibodies to GBM found in most patient s
316
Describe testing of anti-glomemlar basement membrane disease
- Detected by IIF on frozen kidney sections or ELISA for antibody to a 3-subunit
- tissue-bound anti-GBM detected by direct immunofluorence on kidney biopsy sections; produces a smooth, linear, ribbon-like fluorescence along the GBM
317
What are the symptoms of Anti-glomerular basement membrane disease?
-fatigue
- malaise
- edema
- hypertension
- Can progress to renal failure and respiratory problems ( cough, shortness of breathe, hemoptysis
318
What is the treatment for anti -GBM disease?
-high doses of corticosteroids
- immunos oppressive drugs
- plasmapheresis is performed
-
319
What allele has a strong association with anti-GBM disease?
HLA-DRB1-15
320
What detects GBM antibodies currently?
- ELISA
-fluorescent microbead immunoassay that uses recombinant alpha -3(IV) antigen substrates
- confirmation → western blot
