Artificial liver support in the third millennium

Analogous to the artificial kidney there is a need for an effective and safe liver support system to bridge patients with hepatic failure to liver transplantation or own liver regeneration. An over-view is given of the biological and non-biological systems used in clinical practice in the past and at present. The conclusion is drawn that only the biological systems might have the potential to prolong life significantly in patients with acute liver failure. The systems with this potential are summarised. Both in Europe and the USA good bioreactors are available. Most of them are based on porcine hepatocytes, which have immunological and zoonotic drawbacks. What is missing is the well differentiated human hepatocyte in sufficient amounts. Successful development of this cell will be the crown on bioartificial liver research in the third millenium.