Signal amplification methods are widely used in immunohistochemistry (IHC) for detection of rare epitopes and low abundance antigens. While many of these techniques such as the avidin-biotin complex (ABC) method improve staining, they frequently require additional steps and result in higher background staining. Blocking endogenous biotin, a requirement of using ABC reagents, may not sufficiently remove residual activity in frozen tissue sections and tissues high in biotin including the liver and kidney.
