Abstract
The efficacy of protease and ethylenediaminetetraacetic acid, tetrasodium salt dihydrate (EDTA)-Tween 20 in unmasking bovine respiratory syncytial virus (BRSV) antigens in formalin-fixed lung tissue was compared using avidin-biotin immunoperoxidase procedure. Tissues were taken from experimentally infected lambs. BRSV antigen stained in both techniques. Treatment with EDTA-Tween 20 resulted in more intense staining of BRSV infected cells, more uniform cytoplasmic staining, less non-specific background, and superior cellular detail in comparison to protease digestion.