Immunocytochemical detection of peroxisomal beta-oxidation enzymes in cryostat and paraffin sections of human post mortem liver.

The immunocytochemical visualization of the peroxisomal beta-oxidation enzymes was investigated in three human post mortem liver samples. Acyl-CoA oxidase, bifunctional protein and 3-oxoacyl-CoA thiolase remained immunocytochemically detectable 30, 55 and 72 h after death. Peroxisomes in the parenchymal cells were clearly visualized for light microscopy (paraffin and cryostat sections), using protein A-gold in combination with silver enhancement. In two samples catalase activity became very weak, but catalase antigenicity was well preserved. The findings prove the diagnostic value of post mortem samples, even after extreme conditions of tissue conservation. The technique of immunocytochemical staining for the peroxisomal beta-oxidation enzymes on unmounted cryostat sections has not been reported previously. This method allows a quick diagnosis of biopsies from patients suspected of peroxisomal disorders.