Isolation and electrophoretic study on Mallory bodies from the livers of alcoholic cirrhosis.

Mallory bodies (MBs) were isolated from the livers of eight alcoholic patients. The method consisted of homogenization, velocity sedimentation in 60 per cent sucrose solution and two-phase polymer centrifugation using a polyethylene glycol-dextran system. MBs were isolated in large quantity and high purity (more than 95 per cent in some cases). Isolated MBs maintained the characteristic filamentous structures. They were solubilized in 6 M guanidine hydrochloride in 10 per cent or 1 per cent acetic acid by sonication or in 1 per cent sodium dodecyl sulfate with 5 per cent 2-mercaptoethanol and 8 M urea. The solubilized MB protein produced three peaks on Sephadex G-100 chromatography and at least five intense protein bands on sodium dodecyl sulfate polyacrylamide gel electrophoresis. The fractions from control livers contained several bands which were identical with the major components of isolated MB protein. These findings suggest that MBs are not homogeneous protein, but that they are probably complexes of various proteins, and that some components of MBs are present in normal hepatocytes. The exact nature of MBs has yet to be established.