Comparisons of porcine hepatocyte spheroids and single hepatocytes in the non-woven fabric bioartificial liver module.

We previously developed a new bioreactor of the bioartificial liver composed of non-woven fabric. We have also experimented with hepatocyte spheroids, with the aim of improving the efficiency of this NWF bioreactor. In this study, we compared the efficiencies of NWF bioreactors employing hepatocyte spheroids versus single hepatocytes. Hepatocytes were isolated from a whole pig liver by Seglen's method. 1.0 x 10(10) single hepatocytes were immobilized in the NWF bioreactor. Another 1.0 x 10(10) hepatocytes were allowed to form spheroids by 24 hr suspension culture in a 4-L culture vessel, before being immobilized in the bioreactor. Hepatocyte spheroids were found to be functionally superior, on a per-cell basis, to single hepatocytes in the NWF bioreactor. However, the NWF bioreactor employing hepatocyte spheroids exhibited lower efficiency than thaT employing single hepatocytes, because the total number of the hepatocytes had decreased during the 24 hr suspension culture.