Metabolic changes in the recipient after successful liver xenotransplantation in the rat.

MOST hepatic functions are genetically determined and. after liver transplantation. the hepatic parenchyma retains its species specificity. Therefore. in the hamster-to-rat liver xenotransplantation mode!.' we assessed the phenotypic changes of the serum protein profile in the recipient. as well as the functional compatibility between the xenoproteins and the recipient environment. Upon serum protein electrophoresis from a normal rat. a xenotransplanted (OL TX) rat, and a hamster. it was evident that the protein profile of the OL TX rat was closer to the hamster than to the rat. In particular. the rat albumin migrated less than hamster albumin. and an OL TX rat at 180 days after transplantation clearly showed hamster albumin. Six days after transplantation OL TX rat serum samples contained albumin with mixed migration characteristics. Combining electrophoresis and immunofixation techniques we demonstrated the band of migration of complement in the area of the f32-globulins. The OL TX showed a complement band with the same characteristics of the hamster. confirming that in the transplanted rat the main source of complement was of hamster liver origin. By double immunodiffusion assay. using antibodies against rat IgG. it was demonstrated that the IgG in the transplanted rat remained recipient-type. To study the interaction between the hamster complement present in the OL TX serum and the rat IgG, we performed a hemolytic assay. In that test, the OL TX complement was able to lyse SRBC with rat antibodies. with the same efficiency as normal rat complement. Another possible functional interaction between donor and recipient proteins was studied on the OLTX bile. The IgA, that have recipient origin because it is produced by the lymphoid tissue. has to be transported into the bile