Serology Flashcards
Test that involves antigen antibody reaction
Serologic test
Main defense against extracellular organisms
Humoral immunity
Used to detect unknown antigen using known antibody
Forward or direct
Example of forward test
Red cell forward blood typing
Used to detect known antigen using unknown antibody
Backward/indirect or reverse
Physical inactivation of serum
Heat serum at 56C for 30mins
Reinactivation of serum
Heat at 56C for 10mins
Chemical inactivation of Serum
Add choline chloride
Immunologic reaction wherein the combinations of antigen and antibody is not visible
Primary
Immunologic reaction wherein Ab-Ag reaction is visible
Secondary
Immunologically in vivo. Biologic reaction is detectable
Tertiary
Type of antigen involve in precipitation reaction
Soluble antigen
Where optimum precipitation occurs
Zone of equivalence
The number of antigen and antibody is equal
Zone of equivalence
Hypothesis made by Marrack that is based on the assumptions that each antibody molecule must have at least two binding sites, and antigen must be multivalent
Lattice hypothesis
Many free antibody remains in the solution
Prozone
Excess antigen
Postzone
How to prevent prozone and postzone
Proper dilution
Measure of the cloudiness of the solution
Turbidimetry
Measures the light intensity due to reflection, absorption or scatter
Turbidimetry
Measures light that passes through using spectrophotometer
Turbidimetry
Measures the light that is scattered at a particular angle from the incident beam as it passes through a suspension
Nephelometry
Measures scattered light
Nephelometry
Helps to stabilize the diffusion process and allow visualization of the precipitin band
Agar and agarose
No electrical current is used
Passive immunodiffusion
The rate of diffusion is affected by the size of the particles, the temperature, the gel viscosity and the amount of hydration
Passive immunodiffusion
Preferred to agar
Agarose
Antibody was incorporated in a test tube
Oudin test
Single diffusion, single dimension
End result of Oudin test
Precipitin line
Single diffusion, double dimension modification of Oudin test
Radial immunodiffusion
Antibody is uniformly distributed to the support gel, and antigen is applied to a well cut into the gel
Radial immunodiffusion
End result of RID
Precipitin ring
In this technique antigen is allowed to diffuse in completion, and when equivalence is reached, there is no further change in the ring diameter
Mancini or end point method
Measurements are taken before the point of equivalence
Fahey and McKelvey or kinetic method
Square of diameter is directly proportional to antigen concentration
End point method
The diameter is proportional to the log of concentration
Kinetic method
Both antigen and antibody diffuse independently through a semi solid medium in two dimensions
Ouchterlony double diffusion
Smooth arc
Serological identity
Spur
Partial identity
Crossed lines
No identity
Separates molecules according to differences in their electric charges when they are placed in an electric field
Electrophoresis
Combination of RID and electrophoresis
Rocket immunoelectrophoresis
Laurel method
One dimension electroimmunodiffusion
For the identification of monoclonal antibodies
Immunoelectrophoresis
Double diffusion technique with electrophoresis
Immunoelectrophoresis
More sensitive than immunoelectrophoresis
Immunofixation
By grabar and williams
Immunoelectrophoresis
By alper and johnson
Immunofixation
In a precipitation reaction how can the ideal antibody be characterized
High affinity and avidity
Type of antigen used in agglutination reaction
Particulate antigen
Antibody that causes agglutination
Agglutinin
Biggest immunoglobulin
IgM
Non-agglutinating antibody
IgG
Initial combination of antigen and antibody
Sensitization
Formation of large aggregates
Lattice formation
Decreases the buffer’s ionic strength
Low ionic strength saline
Neutralizes the surface charge and allows red cell to approach each other closely
5-30% albumin
What makes red cell negative charge
Sialic acid
Reduces the water hydration around cells
Dextran
Polyethylene glycol
Grade for one solid clump
4+
Questionable grade
1+
Antigen are found naturally occurring on particles
Direct agglutination
Test for typhoid fever
Widal test
Test for typhus fever
Weil felix
What causes typus fever
Rickettsia
Test for Mycoplasma pneumoniae infection
Cold agglutinin
Test for serotypes of salmonella
Kauffman and White
Hemagglutination
ABO blood group
Antigen are not normally found on their surfaces. Artificially attached to a carrier
Passive agglutination
Passive agglutination detects
Antibody
Antibody is attached to a carrier
Reverse passive agglutination
Reverse passive detects
Antigen
Used bacteria as the inert particle to whic antibody is attached
Coagglutination
Based on competition of particulate and soluble antigen for a limited antibody binding sites
Agglutination inhibition
Detects nonagglutinating antibody
Antiglobulin mediated antibody
Detect in vivo sensitization
Direct antiglobulin test
No incubation needed
DAT
In vitro sensitization
Indirect antiglobulin test
Incubation temperature for IAT
37C
Reaction wherein antigen activity is stopped by its specific antibody
Neutralization
A primary immunologic reaction
Labeled immunoassay
