Immunohistochemistry Flashcards
what is immunohistochemistry
the localization of antigens in tissues sections through the use of labelled antibodies and through antigen-antibody complexes, these interactions can be visualised through fluorescent dye, enzymes or colloidal gold.
why is tissue preparation important
allows the protein in the tissues to be preserved
what are indirect methods
methods that involved a primary unlabelled antigen. secondary labelled antigen which forms a link to a tertiary enzyme conjugate complex
why is it important to block endogenous peroxidase activity and how is it done
endogenous peroxidase activity causes a problem in the diagnosis and is done by 0.3% hydrogen peroxide in methanol
why is a specific dilution important for optimisation for the primary antibody
because it can lead to a false positive staining
what does the negative control do
eliminates any case for a false positive
when using DAB what is the expected result
the colour of the cells expressing the antigen should be brown and their nuclei should be blue
when the tissue first gets fixated what do you do
boil in buffer in the microwave to break the tight bonds in the tissue for antigen retrieval
what happens if endogenous peroxidase is not blocked
it will react with dab and give a false postive
