title: Primary cultures of rat hepatocytes as a model system of canalicular development, biliary secretion, and intrahepatic cholestasis.  III. Properties of the biliary transport of immunoglobulin A revealed by immunofluorescence.
abstract: The present study was designed to investigate whether or not the vesicle-mediated, biliary transport of polymeric immunoglobulin A operates in primary cultures of rat hepatocytes. Using immunofluorescence techniques, immunoglobulin A of human or rat origin added to a time-dependent process around and within presumptive bile canaliculi. As a transitory event preceding this accumulation, an intensive particulate fluorescence was detected within the cytoplasm of the hepatocytes. Secretory component could be localized by a faint fluorescence in the cytoplasm and at the margin of bile canaliculi, where the fluorescence was accentuated concomitantly to the accumulation of immunoglobulin A. Translocation of immunoglobulin A could be blocked by an antiserum against secretory component, whereas colostral immunoglobulin A already containing secretory component was not transported. These findings suggest that the pathway for the biliary secretion of immunoglobulin A is active in cultured hepatocytes and provide evidence for the reconstruction of a functionally intact biliary polarity by these cells.
mesh_terms: D000818:Animals; D001648:Bile Canaliculi / Q000502:physiology*; D001653:Bile Ducts, Intrahepatic / Q000276:immunology* / Q000502:physiology*; D001692:Biological Transport; D002478:Cells, Cultured; D002780:Cholestasis, Intrahepatic / Q000276:immunology* / Q000503:physiopathology; D005455:Fluorescent Antibody Technique; D007070:Immunoglobulin A / Q000276:immunology*; D008099:Liver / Q000166:cytology / Q000502:physiology; D008297:Male; D051381:Rats; D011919:Rats, Inbred Strains
chemical_list: D007070:Immunoglobulin A