LSAB is technically similar to standard ABC method.
The first layer is unlabeled primary antibody.
The second layer is biotinylated secondary antibody.
The third layer is Enzyme-Streptavidin conjugates (HRP-Streptavidin or AP-Streptavidin) to replace the complex of avidin-biotin peroxidase.
The enzyme is then visualized by application of the substrate chromogen solutions to produce different colorimetric end products.
The third layer can also be Fluorescent dye-Streptavidin such as FITC-Streptavidin if fluorescence labeling is preferred.
The peroxidase is then developed by the DAB or other substrate to produce different colorimetric end products