Cocultures of porcine hepatocytes and Kupffer cells as an improved in vitro model for the study of hepatotoxic compounds

In this study primary hepatocyte cultures (HC cultures) and cocultures comp rised of hepatocytes and Kupffer cells (HC/KC cocultures) were compared to investigate the inflammatory response induced by lipopolysaccharide (LPS); In addition both culture types were compared to study the hepatotoxic effec ts of two frequently used drugs: tiamulin and chlorpromazine, The inflammatory response in both culture types was determined by measureme nt of tumour necrosis factor-alpha (TNF-alpha), interleukin 6 (IL-6) and ni tric oxide (NO), The drug-induced hepatotoxic effects were determined by me asuring production of intracellular reactive oxygen species (ROS) and cytot oxicity, Exposure of-both cultures to LPS resulted in a significantly increased prod uction of TNF-a, IL-6 and NO. However, the production of TNF-alpha, IL-6 an d NO was substantially increased in culture supernatant of cocultures, comp ared to single HC-cultures, Both tiamulin and chlorpromazine were potent inducers of intracellular ROS production at concentrations greater than or equal to 50 mu M. High ROS pro duction was paralleled by increased cytotoxicity as observed in both cultur e types. Incubation of cocultures with chlorpromazine resulted in a signifi cant increased ROS production as compared to HC cultures. In contrast, no s ignificant differences between HC-cultures and HC/KC cocultures were observ ed for tiamulin induced ROS production or cytotoxicity. The present study demonstrates that cocultures between Kupffer cells and he patocytes provide an excellent model for the study of hepatotoxic compounds which exert (part) of their toxic effects via the activation of Kupffer ce lls. Furthermore they offer a valuable tool to study increased susceptibili ty to intoxication from xenobiotic agents in case of a concurrent or pre-ex isting inflammation.