[Transplantation of allogeneic hepatocytes without immunosuppression: long term survival]

Hepatocyte transplantation could be an alternative to whole liver transplantation. Allogeneic hepatocytes are rejected if transplanted without immunosuppression. The aim of this study was to transplant allogeneic hepatocytes in the peritoneum and to protect them from rejection by encapsulation in a new semi-permeable membrane.

Rats hepatocytes were encapsulated in hydrogel-based hollow fibers, obtained from AN69 polymer, before being transplanted into the peritoneum of rats. Outcome of allogeneic hepatocytes encapsulated in hollow fibers was compared to that of free allogeneic hepatocytes. Cell viability was assessed by erythrosine exclusion, morphology by electronic microscopy and function by albumin release.

Up to 90 days, viability of allogenic hepatocytes in hollow fibers was above 80%. The morphology remained normal at electronic microscopy. Albumin release was 16.5 +/- 0.3 (day 15), 14.2 +/- 2.0 (day 30), 8.8 +/- 0.1 (day 60) and 11.4 +/- 0.3 micrograms/24 h/10(6) hepatocytes (day 90). Free hepatocytes did not survive at day 15.

Viability and function of encapsulated allogeneic hepatocytes were maintained up to 90 days after transplantation, without immunosuppression.