APPEARANCE OF SINUSOIDAL INCLUSION-CONTAINING ENDOTHELIAL-CELLS IN LIVER-DISEASE

Sinusoidal ''inclusion-containing endothelial cells'' were studied his topathologically and immunohistochemically in various liver diseases, and their clinical importance was investigated. A total of 498 needle liver biopsies were examined. Endothelial inclusions inside the cells were recognized as eosinophilic granules in hematoxylin-eosin-stained sections. Electron microscopy showed that these inclusions corresponde d to round cytoplasmic dense bodies with a single limiting membrane. T he contents of these bodies were generally homogeneous, but sometimes heterogeneous. The inclusions appeared to contain protein, but were re sistant to trypsin digestion, and immunohistochemistry failed to ident ify any immunoglobulins or hepatocyte-derived proteins. These endothel ial cells also contained an increased number of micropinocytotic vesic les when compared with ordinary cells. The inclusion-containing endoth elial cells appeared frequently in chronic hepatitis, but were relativ ely rare in other liver diseases, The incidence was higher in chronic aggressive hepatitis than in chronic persistent hepatitis or inactive cirrhosis. Although the density of these cells varied considerably eve n among patients with the same histological diagnosis and the phenotyp ical changes of these endothelial cells, assessed by monoclonal antibo dies, were not apparent, the serum gamma globulin level tended to incr ease in relation to the density of inclusion-containing endothelial ce lls and the correlation was significant in hepatitis C.