Improvement of the effect of hepatocyte isograft in the Gunn rat by cotransplantation of islets of Langerhans

Purpose: Hepatocyte transplantation (HcTX) has been investigated for many y ears as an alternative therapy to orthotopic liver transplantation to treat hepatic congenital enzymatic deficiency disease. The animal model most use d is the Gunn rat, which presents a hyperbilirubinemia caused by the lack o f uridine-diphosphate-glucuronyl-transferase. Some investigators have clear ly described a hepatotrophic effect mediated by islets of Langerhans (IL) w hen transplanted with hepatocytes (Hc). In this study, the functional effec t of cotransplanted IL on hepatocytes (co-HcTX) in Gunn rats in an isograft model is assessed. Methods: Two groups are compared: group 1 (n = 6), HcTX to group 2 (n = 6), co-HcTX. Cells isolated by enzymatic digestion are transplanted directly i nto the splenic parenchyma. Blood samples are taken regularly until day 100 to measure the unconjugated bilirubin (UB). Histological examination of th e spleen is performed at the end of the experiment. Results: Both groups show a significant decrease of the UB: group 1, 47%; g roup 2, 65%. The decrease is statistically more pronounced with co-HcTX. Th e histological analysis shows a trophic effect of the IL on the grafted hep atocytes in the co-HcTX group. Conclusions: The HcTX and the co-HcTX correct partially the hyperbilirubine mia of the Gunn rat. A functional assessment has been performed to evaluate the effect of cotransplanted IL on HcTX. J Pediatr Surg 34:321-324. Copyri ght (C) 1999 by W.B. Saunders Company.