ELISA SERUM PROFILE
Purpose: To quantitate serum antibody to a specific
Viral antigen is precoated onto a microtiter plate.
Serum is added to the coated wells. If antibody is present, it will
bind specifically to the viral antigen. Unbound material is removed by a washing
An anti-chicken antibody conjugated with horseradish peroxidase
enzyme is next added to the viral antigen-antibody complex. This reagent binds to any
chicken antibody that remains in the plate.
Finally, O-phenylenediamine.2HCL (OPD) and hydrogen peroxide
substrate is added to the wells of the plate. When antibody is present, the enzymatic
reaction which occurs results in a color change which can be read visually or by a
Color development and intensity can be directly related to the amount
of antibody in the original serum sample. Commercial kits are available for many of the
poultry diseases (e.g. NC, Br, AE, AI, MG, IBD, REO, and RE). Some laboratories have
automated systems and computers which analyze results and generate a graphic and numerical
quantitate antibody to specific viral avian pathogens.
1. The test has two parts:
Neutralization - The virus and the serum are mixed in a test tube and
incubated for a specified time period. If antibody to the specific virus being tested is
present, it will neutralize the virus.
Assay - The unneutralized virus is assayed in a cell culture system
or in embryonating chicken eggs. The amount of unneutralized virus depends on the amount
of antibody present in the test serum.
2. This is a well established diagnostic and research tool but
compared to the HI and ELISA tests is much more expensive and time consuming.