DIF
Direct immunofluorescence assays: (DIF)
9labeled
antibody is added directly to tissue
9incubation
period
9washing step
to remove any unbound labeled antibody
9viewed using
a fluorescence microscope
9positive test
shows bright fluorescence at site of ag-ab complexes
9negative test
shows no fluorescence
9labeled ag-ab
complexes may also be detected by flow cytometry if specimen is fluid
