INTRODUCTION Many patients with end-stage liver diseases die before a donor liver becomes available (1). Even when liver grafts become available, patients with fulminant hepatic failure (FHF) have problems due to the high mortality rate when the neurologic damage is severe and advanced or when they also have a life-threatening infection (2). As a result, such patients require hepatic liver support. Moreover, since FHF due to certain liver diseases can be reversible, the patients with potentially reversible liver failure need temporary liver assistance in order for their liver function to recover. The development of a bioartificial liver (BAL) using Liver Assist Devices The International Journal of Artificial Organs / Vol. 22 / no. 7, 1999 / pp. 505-510 Efficacy of Nafamostat Mesilate for improving the performance of a bioartificial liver using porcine hepatocytes H. FUJIOKA, S. EGUCHI, N. SUGIYAMA, Y. KAWAZOE, Y. KAWASHITA, Y. KAMOHARA, T. AZUMA, J. FURUI, T. KANEMATSU Department of Surgery II, Nagasaki University School of Medicine, Nagasaki - Japan © by Wichtig Editore, 1999 0391-3988/505-06 $03.00/0 ABSTRACT: Our bioartificial liver (BAL) consists of porcine hepatocytes attached to beads and plasma perfused through the system. The function of our BAL lasts for approximately 7 hours. The objective of the present study was to investigate the efficacy of Nafamostat Mesilate (NM), a protease inhibitor and potent complement inhibitor, for improving the performance of the BAL. The experimental groups were divided as follows; the NM group (n=7) where the BAL had porcine hepatocytes with 3.8x10 -4 M, of NM, and the control group where the BAL had no NM. Plasma obtained from patients suffering from hepatic failure was perfused through the BAL for 10 hours. The viability of the porcine hepatocytes and the levels of alanine aminotransferase (ALT) in the human plasma were measured during perfusion. After the 10-hour perfusion, another human hepatic failure plasma was perfused for an additional 1 hour and then the function of the BAL was evaluated. After the 10-hour perfusion, the viability of the hepatocytes in the NM group was 51± 7 %, whereas that in the control group was rapidly reduced by 35 ± 5 %. Although the levels of ALT in the human plasma in both groups increased with the perfusion time, those in the NM group were significantly lower than those in the control group (p < 0.05). These results suggest that NM prevented damage to the porcine hepatocytes in human hepatic failure plasma as compared to the control group. In the human hepatic failure plasma before perfusion, the partial thrombin time (PT) and the plasma ammonia (NH 3 ) levels were 19.8 ± 12 % and 288 ± 102 μg/dl, respectively. Fischer’s ratios were 0.98 ± 0.39. Even after the 10- hour perfusion, the BAL in the NM group significantly improved the levels of PT (38 ± 10 %; p < 0.05), NH 3 (214 ± 34 μg/dl; p < 0.05) and Fischer’s ratios (1.4 ± 0.3; p < 0.05). On the other hand, the BAL in the control group did not show any improvement in those parameters. In conclusion, NM was found to help in maintaining the viability of porcine hepatocytes in human hepatic failure plasma, thereby allowing the porcine hepatocyte-based BAL to function much better. (Int J Artif Organs 1999; 22: 505-10) KEY WORDS: Human hepatic failure plasma, Bioartificial liver, Porcine hepatocyte Fujioka 9 29-07-1999 10:04 Pagina 505