Term
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Definition
| is the study of in vitro antigen/antibody reactions. Serology techniques are used to isolate and identify a specific antigen or antibody charachteristic of a disease, infection or condition. |
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Term
| To obtain a patient diagnosis (serology), one of the following is used. |
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Definition
- A known antibody to determine if a patients serum has a specific antigen
- A known antigen to determine if a patient has produced specific antibodies against an infectious agent.
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Term
| Serological tests detect the combination of __________ and ________. |
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Definition
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Term
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Definition
| Process by which insoluble antigens aggregate to form larger complexes when a specific antibody is present |
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Term
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Definition
| The formation of an insoluble complex composed of soluble antigen and soluble antibody to produce insoluble complexes that are visible. |
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Term
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Definition
| Zone at which optimal precipitation occurs. |
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Term
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Definition
| Compliment causes hemolysis through a complex process known as the complement cascade. Hemolysis is the lysis of RBCs. |
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Term
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Definition
| Substance used to visualize antigen/antibody reactions in the laboratory. |
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Term
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Definition
Concentration or strength of an antibody
Expressed as the highest dilution of the serum that produces agglutination. |
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Term
| All serology tests have what three main components? |
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Definition
An antibody
An antigen
An Indicator |
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Term
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Definition
| Have a wide range of applications in the clinical diagnosis of noninfectious immune disorders and infectious disease. Visible expression of the aggregation or clumping of antigens and antibodies, antigens or antibodies are absorbed onto the surface of particles known as carriers. |
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Term
| What are four types of carriers used in agglutination testing? |
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Definition
- Latex particles
- Colloidal charcoal
- RBCs
- Bacterial cells
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Term
| What are the two steps to agglutination? |
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Definition
Sensitization: Initial binding of antibody molecules to antigens.
Lattice Formation: Visible cross-linking reaction occurs (clumping). |
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Term
| What are the factors that affect agglutination? |
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Definition
Temperature (IgM 4-27C & IgG 30-37C)
Incubation time
pH
Antigen/Antibody ratio |
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Term
| What are 5 types of agglutination tests? |
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Definition
- Latex agglutination test
- Antistreptolysin O Antibody
- Flocculation Test
- Hemagglutination Methods
- Monospot
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Term
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Definition
| Antibody molecules are bound to latex beads. Normal values reveal no agglutination, if there is an antibody/antigen match agglutination will occur. |
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Term
| What is the clinical significance of the latex agglutination test? |
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Definition
C-reactive protein (C4)
IgG & IgM Rheumatoid Factors
Rubella antibody
Neutralization of toxins, protect against circulating bacteria and viruses. |
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Term
Anti-Streptolysin O Antibody test
or ASO Antibody test |
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Definition
| The test that measures antibodies against strptolysin O, a substance produced by Group A Streptococcus Bacteria. This type of bacteria causes infections such as Strep throat, Scarlet Fever, Skin infections such as impetigo and cellulitis. Latex agglutination test in which latex particles are coated with streptolysin O antigen. |
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Term
| Disease manifestations & clinical correlations of ASO antibody test. |
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Definition
| Elevated titer suggests presence of group A streptococcal infection. Streptococcal skin infections can produce low ASO titers. Low titers can exist in healthy persons due to frequency of strep infections. |
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Term
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Definition
| Test for antibody detection based on interaction of soluble antigen with antibody. Results in the formation of a precipitate of fine particles. Particles are macroscopically or microscopically visible. |
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Term
| Flocculation test - clinical significance |
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Definition
Syphilis VDRL
Syphilis RPR |
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Term
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Definition
| Agglutination involving RBCs |
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Term
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Definition
| Detects antibodies to erythrocyte antigens. Antigens can be natural (direct) or bound to RBC (passive). |
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Term
| Hemagglutination Methods - Clinical Significance |
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Definition
ABO blood group typing antibodies
Rh antigens
Hepatitis B and C
HIV I and II |
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Term
| Grading Agglutination Reactions |
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Definition
Negative - No aggregates
Mixed Field - Few isolated aggregates, mostly free floating cells, supernatant appears red.
Weak (+/-) - Tiny aggregates that are barely visible macroscopically, many free RBCs, turbid and reddish supernatant.
1+ - A few small aggregates just visible macroscopically
2+ - Medium sized aggregates
3+ - Several Large aggregates
4+ - One solid aggregate |
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Term
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Definition
| The formation of an insoluble complex composed of soluble antigen and soluble antibody to produce insoluble complexes that are visible. Not widely used in a general laboratory setting. |
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Term
| Double immunodiffusion test |
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Definition
| Also called ouchterlony double diffusion technique, used to determine relatedness between antigens. Antigen and antibody specific to each other will for an immune complex that will precipitate as a visible line in a gel. |
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Term
| Double Immunodiffusion Test - Interperetation |
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Definition
Identity - Smooth arc
Non-Identity - lines cross each other
Partial Identity - Spur |
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Term
| Clinical significance of Double Immunodiffusion Test Method |
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Definition
- Identification of fungal antigens
- Detection of antibodies to extractable nuclear antigens
- RA
- SLE
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Term
| Immuno-electrophoresis (IEP) |
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Definition
| Method combines diffusion with electrophoresis to speed up and sharpen results. As diffusion takes place distinct precipitin bands are formed. |
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Term
| Countercurrent Immuno-electrophoresis |
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Definition
| An electrical current is added to help antigens and antibodies move toward each other more quickly than simple diffusion. Agarose gels are used and the pH is chosen so that antibodies are positively charged and antigens are negatively charged. When a zone of equivalence is reached the antigen-antibody complex for a visible precipitin line |
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Term
| Clinical applications of Electroimmunodiffusion Methods |
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Definition
Antinuclear ribonucleoprotein
Radioimmunoprecipitation |
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Term
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Definition
| Antigens are electrophoresed in an antibody containing gel, precipitin bands are formed resembling a rocket, height of the rocket is proportional to the antigen concentration. |
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Term
| Immunofixation Electrophoresis |
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Definition
| A two stage procedure using agarose gel protein electophoresis followed by immunoprecipitation. Monospecific antisera are applied to five of the electrophoresis patterns. A protein fixative solution is applied to the sixth pattern to produce a complete reference pattern. If antigen present, antigen-antibody forms a precipitate. |
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Term
| Clinical applications of Immunofixation Electrophoresis. |
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Definition
| Used primarily for identification of monoclonal immunoglobulins. |
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Term
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Definition
| A reagent (antigen or antibody) that is tagged with some component that allows detection or visualization. |
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Term
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Definition
| are designed for antigens and antibodies that may be small in size or present in very low concentration.. Their presence is determined indirectly using a labeled reactant to detect whether or not specific binding has taken place. |
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Term
| List 5 Labeling Techniques |
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Definition
Radioimmunoassay (RIA)
Chemiluminescence
Enzyme Immunoassays (EIA)
Immunofluorescent Techniques
Antinuclear Antibody (ANA) |
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Term
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Definition
| Relies on the principle of competitive binding. The analyte being detected competes with a radiolabeled analyte fora limited number of binding sites on a high-affinity antibody. |
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Term
| Radio-immunoassay (RIA) - Clinical Applications |
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Definition
Hepatitis A IgM antibody
Hepatitis A antigen |
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Term
| Immuno-radiometric Assay (IRMA) |
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Definition
| Same method as RIA but uses two monoclonal antibodies of high affinity. |
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Term
| What are the advantages of IRMA? |
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Definition
| Faster reaction rate, increased sensitivity. |
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Term
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Definition
| defined as the luminescence in which the light emission is caused by the products of a specific chemical reaction. Has supplanted most RIA in the clinical laboratory. |
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Term
| Advantages of Chemiluminescence |
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Definition
| Excellent sensitivity and dynamic range, does not require sample radiation, nonselective excitation and source instability are eliminated. |
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Term
| What are the two types of Chemiluminescence? |
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Definition
Competitive Immunoassay
Sandwich Immunoassay |
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Term
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Definition
| A fixed amount of labeled antigen competes with unlabeled antigen (patient sample) for a limited number of antibody-binding sites. |
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Term
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Definition
| Sample antigen binds to an antibody fixed onto a solid phase. A second antibody labeled with chemiluminescent label binds to the antigen-antibody complex on the solid phase. |
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Term
| Quality control for chemiluminescence. |
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Definition
| Control sera should be used |
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Term
| What are the clinical applications of Chemiluminescence? |
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Definition
Hepatitis A IgM antibody
Hepatitis A antigen |
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Term
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Definition
| are naturally occuring molecules that catalyze certain biochemical reactions. React with suitable substrates to produce breakdown products that may be chromogenic, flurogenic, or luminescent. |
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Term
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Definition
Alkaline Phosphatase
Horseradish Peroxidase
Beta-galactosidase |
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Term
| Enzyme Immunoassays (EIA) |
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Definition
| A plastic bead or plastic plate is coated with antigen. The antigen reacts with antibody in the patient serum. Most commonly used enzymes are peroxidase and alkaline phosphatase. |
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Term
| Immunoflouorescent Techniques |
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Definition
| flourescent molecules are used as labels, techniques include direct and indirect immunoflourescent assay. |
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Term
| Direct Immunofluorescent Assay |
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Definition
Best suited for antigen detection
Antibody conjugated with a fluorescent tag is added directly to unknown antigen that is fied to a miroscope slide. After incubation, wash, the slide is read using a fluorescence microscope, visualized as bright apple green. |
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Term
| Indirect Immunofluorescent Assay |
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Definition
Used for both antigen and antibody identification.
Patient's serum is diluted and placed on the slide to cover the antigen source.... conjugated marker for human antibody will bind to the antibody already bound to the antigen on the slide and will serve as a marker for the antibody when viewed under a fluorescent microscope. |
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Term
| Clinical applications of Direct Immunofluorescence |
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Definition
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Term
| Clinical significance of Indirect Immunofluorescence |
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Definition
| The serological method most widely used to detect diverse antibodies. ANAs are frequently assayed using this method. |
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Term
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Definition
| Indirect Immunofluorescence is the preferred method for initial screening. Antigen substrate from tissue containing nuclei is fixed to a slide. Most common tissues used are mouse liver or kidney, or cell-cultured fibroblasts grown on slides. If antibody present in patients's serum it will attach to nuclei in the substrate. |
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Term
| Clinical correlation of ANA screening test. |
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Definition
| The presence of ANA antibodies can indicate various systemic autoimmune connective tissue disorders (hallmark of patients with SLE) |
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Term
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Definition
| Test has two components. Indicator system; Sheep RBCs, anti-sheep antibody, and complement from guinea pig serum. And known antigen and patient serum. |
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Term
| In the compliment fixation test, hemolysis of indicator sheep cells indicates what? |
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Definition
| a lack of antibody (negative complement fixation test) A positive Complement Fixation test will be demonstrated by the lack of hemolysis because the patient serum does contain a complement fixing antibody. |
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Term
| Clinical applications of the Complement Fixation test. |
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Definition
Rubella virus
Varicella-zoster virus
Herpes simplex infection |
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