Morphologic studies of hepatocytes entrapped in hollow fibers of a bioartificial liver

A bioartificial liver cartridge was prepared by inoculating porcine hepatoc ytes into the inner space of hollow fibers of a hemodialyzer. The hepatocyt es formed rod shaped cell aggregates during in vitro perfusion culture with in 1 day. Morphologic examination was carried out on the aggregates by opti cal and electron microscopy. Each hepatocyte was in direct contact with adj acent cells and a bile canaliculus-like structure was occasionally seen bet ween hepatocytes. High magnification observation showed that the canaliculu s was separated from the remainder of the intercellular space by a tight ju nction. These facts suggest that the hepatocytes formed functionally associ ated cell aggregates with a compact morphology not unlike hepatocyte sphero ids. These structures were well maintained for 7 days in culture, and then the amorphous area in the aggregates and the nonviable cell number increase d with lengthening culture period. The bioartificial liver maintained the a bility to metabolize lidocaine, ammonia, and galactose for 7 days and then deteriorated with time.