Use of a monoclonal antibody against Lafora bodies for the immunocytochemical study of ground-glass inclusions in hepatocytes due to cyanamide.

AIMS: Ground-glass inclusions (GGIs) in hepatocytes are known to be associated with cyanamide treatment in patients with alcohol dependency. The purpose of this study was to assess the reactivity of a monoclonal antibody (MAb) raised against polyglucosan and to detect early events in GGI formation. METHODS AND
RESULTS: Formalin-fixed paraffin-embedded liver tissues from four patients treated with cyanamide were used. Sections were stained with haematoxylin and eosin and periodic acid-Schiff with and without diastase digestion, and were immunohistochemically stained with the MAb. For electron microscopic study, routinely processed liver tissue from one patient was examined with conventional and immunoelectron microscopy with use of the MAb. All specimens from the four cyanamide-treated patients contained GGIs in the cytoplasm of hepatocytes, and these GGIs reacted intensely with the MAb. Fully developed GGIs contained various organelles, whereas early ones consisted primarily of glycogen granules and dilated smooth endoplasmic reticulum. In immunoelectron microscopic preparations, gold particles were located within GGIs, and the immunolabelled organelles appeared to be glycogen granules.
CONCLUSIONS: This novel MAb is useful for the detection of GGIs caused by cyanamide. Our results support the idea that GGI formation may result from specific abnormalities in glucose metabolism.