|What is WesternBlot?|
Whereas ELISA measures antibody to whole virus and gives a "positive," "negative" or indeterminate test result, western blotting is a more specific test. It allows one to visualize antibodies directed against each viral or bacterial protein. For this reason, WesternBlot is a confirmatory test for a positive ELISA tests.
For example, for specific HIV diagnostic test, HIV infected cells are lysed, subjected to SDS-PAGE (sodium dodecyl sulphate polyacrilamid gel electrophoresis) and blotted onto a membrane as described above. The membrane was blocked, cut into strips and incubated with the serum samples from each patient as indicated.
Below you can see an example of a Western Blot and how to interpret it.
Viral Proteins (HIV) and Band Pattern Interpretation
Viral Proteins - HIV, like any other virus, is composed of a number of different proteins. The Western Blot positive control lane contains proteins from patient sera as well as HIV proteins. HIV positivity can therefore only be confirmed by the presence of the following types of proteins:
Band Pattern Interpretation
In 1987 the Centre for Disease Control along with several other organizations established criteria for serologic interpretation of HIV WesternBlot tests. The criteria are listed below:
You can see also Helicobacter Pylori Westernblot Interpretation