Liver Sinusoidal Cells

Abstract

Sequestration and degradation of red blood cells (RBC) are believed to occur in part in the liver, but the magnitude and cellular localization of this process remain uncertain. This problem was studied in rats by investigating isolated parenehymal and sinusoidal cell populations of the liver. After digesting the perfused liver with pronase, hepatic sinusoidal cells were isolated free of RBC and debris. Of the isolated cells, 90 % were phagocytic, as judged by their uptake of colloidal ~gSAu or of aggregated albumin-lalI administered in vivo After administration of spherocytic (heat-treated) RBC, however, only about one quarter of the isolated cells were found to contain phagocytized RBC. This apparently distinct popula~ tion of RBC-phagocydzing cells is designated as '°erythrophagocytic (EP)" ceils. The EP cell population was further characterized functionally by its specific phagocytosis of coltoidaI carbon and of 99mtechnetium-sulfur colloid and histochemically by its peroxidase activity. The role of the EP population in the catabolism of RBC-hemoglobin was studied in isolated hepatic sinusoidal ceils by assay of microsomal heme oxygenase (MHO), which is the inducible enzyme system that converts heine to bilirubin. The MHO activity of individual sinusoidal isolates was related directly to their content of EP ceils

The origin, kinetics, and characteristics of the kupffer cells in the normal steady state

“…In cytocentrifuge preparations the Kupffer cells were morphologically heterogeneous in size and shape as other workers have noted (6,7,20,37). In Giemsa-stained preparations the cell size ranged from 7 × 7 to 15 × 14 gm; the cells had a distinct basophilic cytoplasm and the nucleus was eccentrically located and was usually oval or indented (Fig.…”

“…Our total yield of 2.3 x 107 nonparenchymal cells per g liver compares very favorably with those of other workers using similar methods who obtained in mice, rats, etc., yields varying from 0.58 to 2.2 x 107 nonparenchymal cells per g liver (18,20,23,28,31,41). The percentage of Kupffer cells in the cell suspension of our mice averaged 26.9%, giving a total of 0.91 x 107 Kupffer cells per liver, which is similar or a little lower than that obtained by others in normal rats by using the same method (18,20) or other methods (23).…”

“…Of all the various methods of preparing isolated Kupffer cells pronase digestion seems to give the best results in terms of structure and function and freedom from hepatocyte contamination (18,20,30,31).…”

“…Early attempts relied on magnetic and mechanical methods (26) which have now been superseded by enzymatic ones (23,(27)(28)(29)(30). A combination of pronase and DNAase, first used by Bissell et al (20) has been shown to give the best yield and to cause little damage to the Kupffer cells (18,30,31). This is the method used in the present study.…”

“…Cytochemically the Kupffer cell has been shown to possess a diffuse cytoplasmic esterase activity (17,18) while peroxidase activity is found in the rough endoplasmic reticulum and nuclear envelope but not in the granules (4,(18)(19)(20)(21).…”