A study on Mallory bodies. Isolation, ultrastructure and preliminary biochemical characterization of Mallory bodies from livers of alcoholic cirrhosis and malignant hepatoma.

Mallory bodies (MBs) were isolated from the livers of 8 alcoholic patients and a malignant hepatoma occurring in a non-alcoholic patient. MBs were isolated in large quantity and high purity. The isolates were devoid of liver cell organelles except in the case of malignant hepatoma where dense and membranous material resembling nuclear substances and endoplasmic reticulum were found. The "nuclear" material had continuity with MBs. Electron microscopic examination suggested the presence of a dense body and very fine filaments within in situ and isolated MBs in addition to the tubular structure of so-called MB fibers. Amino acid analysis indicated that the major component of MBs is a protein which does not contain unusual amino acids or any particular amino acid in a large quantity to characterize this protein. The isolated fractions were solubilized in 6 M guaindine hydrochloride by sonication or in 1% sodium dodecyl sulfate (SDS) with 2 mercaptoethanol and 8 M urea. The solubilized MB protein produced 3 peaks by Sephadex G 100 chromatography and at least five intense protein bands by SDS polyacrylamide gel electrophoresis. Serum sample and the fractions from control livers contained several protein bands which were similar to the major components of isolated MB protein. These morphological and biochemical findings suggest that MBs are not homogeneous protein, but they are probably complexes of various proteins and that some components of MBs are present in normal hepatocytes.