Scanning electron microscopy of the hepatocyte cytoskeleton in human liver tissue

Portions of eight human livers taken by wedge biopsy or needle biopsy were extracted with 0.5% Triton X-100 and then studied by scanning electron microscopy and immunoelectron microscopy. The wedge-biopsy specimens were perfused with the detergent solution. Needle-biopsy specimens were quickly frozen and cracked and then the cracked tissue was immersed in the detergent solution. The three-dimensional filament network of hepatocytes was visualized. A dense network which consisted of intermediate filaments and microfilaments was observed within the cytoplasm of hepatocytes. These filaments were better preserved in the needle biopsies which were quick-frozen and cracked before extraction than in the wedge biopsies. Variation in the amount of the cytoskeletal filaments was less prominent in the hepatocytes treated by rapid freezing. It is concluded that freeze-cracking is the most favorable method for the study of cytoskeletal pathology in various liver diseases in man.