Long‐term maintenance of hepatocyte functional activity in co‐culture: Requirements for sinusoidal endothelial cells and dexamethasone

Sinusoidal cells isolated from adult rat liver have been established in primary culture and in cell line. The presence of factor VIII R:Ag and peroxidatic/phagocytosis activities were the criteria used to distinguish in freshly isolated cells the endothelial cells from the Kupffer cells and suggested the endothelial origin of the cell line. Using a co‐culture system, the effect of sinusoidal liver cells on hèpatocyte functional activity was characterized. A plateau in which the state of differentiation was stabilized could be generated for co‐cultured hepatocytes isolated from adult rat and a disappearance of the initial expression of α 1 ‐fetoprotein (AFP) and the increase and/or maintenance of albumin secretion were measured with co‐cultured hepatocytes isolated from suckling rat. The presence of dexamethasone was required for such beneficial effect. The hepatocyte‐stabilizing activity was also produced by a pulmonary endothelial cell line.