SEROLOGY INTRO, PRECIPITATION & AGGLUTINATION REACTIONS, LABELED IMMUNOASSAY Flashcards
Complement are inactivated by
Heating to 56 deg C for 30 mins - physical (VDRL-SYPH)
Choline chloride - chemical (RPR)
When more ___ hours has elapsed since inactivation, a specimen can be rein activated by heating it to ______ for ____
4 hours ; 56 deg C ; 10 mins
Serologic test that detects unknown antigen in specimen by using known or commercial anti-sera
Direct
Short storage of serum
2 deg C and & 8 deg c for up to 72 hours
Immunologic reaction ; Combination of a antigen-antibody ; non visible reaction
Primary
Immunologic reaction ; demonstrates antigen-antibody reaction
Secondary
Immunologic reaction ; immunologically in vivo ; biological reaction is detectable
Tertiary
First note by Kraus in 1897
Precipitation reaction
Involves combining SOLUBLE ANTIGEN with SOLUBLE ANTIBODY to produce INSOLUBLE COMPLEXES that are visible
Precipitation reaction
Optimum precipitation occurs in the
Zone of equivalence
Antibody excess occurs in the ____
Prozone
Antigen excess occurs in the ____
Post zone
Measures the reduction in light intensity caused by reflection, absorption, scatter
Turbidimetry
Measures light that is scattered in particular angle ; the amount of light scattered is an INDEX of the solution concentration
Nephelometry
No electrical current ; rate of diffusion is affected by the size of the particles, temperature, the gel viscosity, and the amount of hydration ; longer turn around time
Passive immunodiffusion
Single diffusion, single dimension
Single diffusion, double dimension
Double diffusion, double dimension
These are all examples of?
Passive immunodiffusion
Aka Oudin test ; end product precipitin line ; semi quantitative
Single diffusion, single dimension
Aka radial immunodiffusion ; precipitin ring end product ; quantitative: diameter is directly proportional to concentration ; ab is uniformly distributed in the support gel and antigen is applied to a well cut into the gel
Single diffusion, double dimension
Aka kinetic diffusion ; 19 hours ; diameter is proportional to log of the concentration
Father and Mckelvey method
Aka endpoint diffusion ; square of diameter is proportional to the concentration
Mancini method
Both antigen and antibody diffuse independently through a semisolid medium in two dimension, horizontally and vertically
Double diffusion, double dimension
In Double diffusion, double dimension, antibody hat is ____ is placed in the central well and different antigens are placed in the surrounding wells to determine if the antigens share identical epitopes
Multiseptic
Double diffusion, double dimension pattern : serological identity or the presence of a common epitope
Pattern 1 - arc pattern
Double diffusion, double dimension pattern : compared antigens share no common epitopes
Pattern 2 - crossed lines
Double diffusion, double dimension pattern : partial identity
Pattern 3 - spur formation
A technique that separates molecules using electrical current
Electrophoresis
A _____ is forced through gel, causing antigen, antibody, or both to migrate
Direct current
As diffusion takes place in electrophoresis, distinct _______ are formed
Precipitin bands
Radial immunodiffusion + electrophoresis
Rocket electrophoresis
In rocket electrophoresis, the total distance of antigen migration and precipitation is directly proportional to ______
Laurell technique
Double diffusion + electrophoresis
Immunoelectrophoresis
In immunoelectrophoresis, a _______ is then cut in the gel parallel to the line of separation ; useful procedures for the identification of _______
Trough ; monoclonal proteins
Immunoprecipitation + electrophoresis
Immunofixation electrophoresis
In immunofixation electrophoresis, _____ is applied directly to the gel’s surface rather than placed in a trough
Antiserum
Immunofixation electrophoresis is used to identify and characterize ______
Serum or urine proteins
Bands exhibited by hypogammaglobulinemia
Faintly staining bands
Bands exhibited by polyclonal hypergammaglobulinemias
Darkly staining bands in the gamma region
Bands exhibited by monoclonal antibody
Dark and narrow bands in specific lane
First demonstrated by Gruber and Durham in 1896
Agglutination reactions
A process by which PARTICULATE ANTIGENS such as cells aggregate to form larger complexes when a specific antibody is present
Agglutination reactions
Antibodies that cause agglutination
Agglutinins
Initial antigen-antibody formation
Sensitization
Clumping after centrifugation
Lattice formation
Antigens are found naturally on the surface of the particles
Direct agglutination
Blood typing
Kauffman and white serotyping
Widely test
Weil Felix test
Cold agglutinin test
These are all examples of tests with what type of agglutination reaction??
Direct agglutination
Antigen is artificially attached to a particulate carrier (e.g.cells, latex, bentonite, colloid in, charcoal)
Passive agglutination
Agglutination reactions that detects antibodies to virus such as rotavirus, cytomegalovius, rubella, Varicella-zoster, HBV, HIV, HCV
PASSIVE AGGLUTINATION
In reverse passive agglutination, these are attached to particulate carries
Antibodies
In reverse passive agglutination, _______ of antibody are facing outward
Active sites
Reverse passive agglutination is used to detect ______
Microbial antigens
Uses antibodies bound to a particle to enhance the visibility of agglutination
Co-agglutination
Carrier in co-agglutination
Bacterium
Staphylococcus aureus with Protein A
Co-agglutination
Based on competition between particulate and soluble antigens for limited antibody combining sites
Agglutination-inhibition
An indication of a positive agglutination-inhibition reaction
Lack of agglutination
Involves haptens attached to carrier particles
Agglutination-inhibition
Specific type of precipitation that occurs over a narrow range of antigen concentration ; antigen consists of very fine particles that clump together in a positiver reaction
Flocculation
An example of test that uses flocculation
Non-treponemal tests (RPR & VDRL)
Antigenic activity is stopped by its specific antibody ; highly insensitive because they only rely on a high enough concentration of the unknown
Neutralization
Precipitation and agglutination are considered ______ because a marker label is not needed to detect the reaction
Unlabeled immunoassay
Designed for antigens and antibodies that may be small in size or present in very low concentrations
Labeled immunoassay
Used to detect whether or not specific binding has taken place
Labeled reactant
All reactants are mixed SIMULTANEOUSLY ; labelled antigen competes with unlabeled patient antigen for a limited number of antibody binding sites
Competetitve
labelled antigen competes with unlabeled patient antigen for a limited number of
antibody binding sites
CAPTURE ANTIBODY is first passively absorbed to as solid phase such as micro titer plates, nitrocellulose membrane or plastic beads ; excess antibody is present so that any patient antigen present can be captured
Noncompetitive
The amount of bound label is ________ proportional to the concentration of the labeled antigen
Inversely
NONCOMPETITIVE LABELED IMMUNOASSAY
_______ is the allowed to react with and be captured by the solid-phase antibody ; the amount of label measures is _____ proportional to the amount of patient antigen
Unknown patient antigen ; directly proportional
LABELED IMMUNOASAY
Require a step to physically separate free from bound analyte
Heterogenous
HETEROGENOUS LABELED IMMUNOASSAY
_______ is attached by physical adsorption; when specific binding takes place, complexes remain attached to the solid phase ; the sample is then ______ and the remaining activity is determined
Antigen/antibody ; thoroughly washed
LABELED IMMUNOASSAY
Do not need a SEPARATION STEP ; activity of the label attached to the antigen is diminished when binding of a antibody and antigen occurs ; Simpler to perform because there is NO WASHING STEP
Homogenous
Pioneered by Yalow and Berson in the late 1950s
Radioimmunoassay
_____ have nuclei that decay spontaneously, emitting matter and energy ; uses ________ as label
Radioactive elements ; radioactive substances
Gamma counter
Iodine-131 ; Iodine-125
Beta counter
Hydrogen-3 ; carbon-14
Most common radioactive label
Gamma counter - Iodine-125
Radioactivity is measured by a ________
Scintillation counter
Radioactive in the solid phase is ______ proportional to analyte concentration
Inversely
Antigen (sample) + antibody (reagent) + radioactive antigen ; most sensitive for drug assay, hormone
Competitive RIA
____ Antigen (Sample) + radioactive antibody ; Amount of radioactivity is ____ proportional to the concentration of analyte
Non-competitive RIA ; directly proportional
IRMA (immunoradiometric assay) is an example of what type of RIA
NON COMPETITIVE RIA
In 1941, he demonstrated that antibodies could be labelled with molecules that fluoresce (fluorescent immunoassay)
Albert Coons
Most common fluorescent immunoassay
Fluorescein isothiocyanate
ANTIBODY that is conjugated with a fluorescent tag is added directly to unknown ANTIGEN that is fixed to a microscope slide
Direct immunofluorescent
Patient is incubated with a KNOWN ANTIGEN attached to a solid phase such; washed and an ANTI-HUMAN containing a fluorescent tag is added
Indirect immunofluorescence
FTA-ABS and FANA are examples of what type of immunofluorescent
Indirect immunofluorescent
Based on the change in polarization of fluorescent light emitted from a labeled molecule when it is bound by antibody ; the degree of fluorescence polarization is ____ proportional to concentaration of the analyte
Fluorescence polarization immunoassay ; inversely proportional
______ is used to measure the amount of polarized light
Polarization analyzer
Disadvantage of fluorescence polarization immunoasay
Quenching = low fluorescence
Enzyme immunoassay
React with suitable substrates to produce breakdown products:
Chromogenic, fluorogenic, or luminscent
Enzyme-labeled antigen competes with unlabeled patient antigen for a limited number of binding sites on antibody molecules that are attached to a solid phase
Competitive EIA
Enzyme activity is _______ proportional to the concentration of the analyte
Inversely
Indirect immunoassay ; the amount of color, fluorescence, or luminescence detected ______ proportional to the amount of antibody in the specimen
Non competitive EIA ; directly
Microtiter plates
Nitrocellulose membranes
Magnetic
Latex plastic beads
These are used as a ____ in non competitive EIA
Solid-phase support
Non competitive EIA is used to measure ______ to infectious agents that are difficult to isolate in the lab and autoantibody testing
Antibody production
Rapid, simple to perform, adapt easily to automation (e.g. enzyme multiplied immunoassay technique — EMIT) ; for determination of hormones, therapeutic drugs, and drugs of abuse
Homogenous assay
Emission of light caused by a chemical reaction
Chemiluminescent immunoassay
Chemiluminescent immunoassay is measure in
Luminometer