Study Set Content:
Kell blood group antigen has about
3500 to 6000 sites/RBC
an important physiochemical effect that influences antibody uptake by cell surface antigens.
Steric Hindrance
dissimilar antibodies with approximately the same binding constant are directed against antigenic determinants located close to each other will compete for space in reaching their specific receptor sites.
Steric Hindrance
occur whenever there is a conformational change in the relationship of an antigenic receptor site to the outside surface
Steric Hindrance
Optimum pH
6.5 to 7.5
high electrolyte concentrations act to neutralize what?
net negative charge of particles
antibodies that are cold-reacting
IgM
Thermal range of IgM
4°C to 22°C or [39° F to 72° F]
antibodies that are warm reacting
IgG
Optimum Temperature of reaction of IgG
37° C (98.6° F)
In laboratory testing, incubation times range from how many minutes
15 to 60 minutes
Store equipment and reagent in clean, dust-free environment, and handle with care.
Use negative quality control (QC) steps.
contaminated equipment
Causes of False-Positive Agglutination Test Reactions
Contaminated Equipment, Autoagglutination, Delay in reading slide reactions resulting in drying out of mixture, Overcentrifugation
Causes of False-Negative Agglutination Test Reactions
Inadequate washing of RBCs in AHG testing, Failure to add AHG reagent, Contaminated reagents, improper incubation, Delay in reading slide reactions, Undercentrifugation, Delay in reading slides, Prozone Phenomenon
Types of Agglutination Reaction
- Direct Agglutination
- Passive Agglutination
- Reverse Passive Agglutination
- Coagglutination
- Agglutination Inhibition
- Antiglobulin-mediated Agglutination (DAT & IAT)
Antigens are found naturally on the surface of the particle
Direct Agglutination
was naturally adsorbed to the surface of polystyrene latex particles
IgG
a rapid screening test used to help determine the possibility of typhoid fever
Widal Test
for serotyping Salmonella spp. based on surface Ags:
Kauffman-White Scheme
Somatic Antigen
O Ag
