HYDRATED AUTOCLAVE PRETREATMENT ENHANCEMENT OF PRION PROTEIN IMMUNOREACTIVITY IN FORMALIN-FIXED BOVINE SPONGIFORM ENCEPHALOPATHY-AFFECTED BRAIN

The efficacy of three pretreatment techniques for the detection of pri on protein (PrP) in formalin-fixed, paraffin-embedded bovine spongifor m encephalopathy (BSE) - affected brain tissue were compared using aut omated image analysis. The most abundant immunostaining was in the for m of particulate expression observed in sections pretreated with hydra ted autoclaving for 30 min. Considerably less immunostaining occurred in sections pretreated with formic acid and no specific particulate im munostaining was detected in sections pretreated with hydrolytic autoc laving. Hydrated autoclaving pretreatment of sections prior to PrP imm unolabelling gives visualisation of widespread sites of abnormal PrP d eposition in the brain, allowing detailed study of the form and distri bution of the protein in routinely fixed bovine central nervous system affected with BSE.