Successful clinical liver transplantation should make it possible to more incisively explore certain aspects of hepatic function in man. In the present study this has been done by examining the haptoglobin (Hp) and group specific component (Gc) of the alpha 2 globulin serum fraction of 4 infant recipients of orthotopic liver homografts and their donors. The results establish that both protein moieties are manufactured exclusively by the liver. They also provide evidence that liver homografts retain the metabolic specificity of the donor after transfer to a new host.The previous reports of Smithies on Hp (1,2) and of Hirschfeld on Gc (3,4) provided the basis for the experimental approach. They showed that 3 kinds of both Hp and Gc were identifiable in the human population, that the type present in any individual was subject to genetic control, and that the phenotypic expression could be identified with electrophoretic techniques.
Materials and MethodsThe 4 liver recipients were females, aged 13-21 months at the time of transplantation. The first patient had a hepatoma; the other 3 had congenital biliary atresia. The cadaveric donors were 2 males and 2 females, aged 14-20 months. Three of the 4 children are still alive, now 180, 136, and 56 days after operation; the fourth died 61 days posttransplantation. A more general account of these cases is published elsewhere (5).Serum samples were taken from both the donors and recipients prior to transplantation; in Case 1, the parents' sera were also analyzed in order to confirm the Hp genotype. Postoperatively, recipient samples were obtained at variable intervals. The serum Hp genotypes were determined by electrophoresis in a vertical starch gel 1 (6). The wells were charged with a solution consisting of 15 parts of undiluted serum and one part of 10% human hemoglobin solution. The initial current was 6 mA. A constant voltage of 120 was maintained for 24 hours. The gel was removed from the supporting tray and divided horizontally into slices 2-3 mm thick. The gel slice was stained in 0.1% o-tolidine in 1% acetic acid and a few drops of 30% H 2 O 2 were added.The determination of serum Gc genotypes was made by Hirschfeld's modification (7) of the microimmunoelectrophoresis 2 technique of Scheidegger (8). Commercial horse anti-Gc antiserum and rabbit anti-Gc antiserum were used 3 . Electrophoresis was at 220 volts for 2.5 hours with a discontinuous buffer system (pH 8.6, μ = 0.05 in agar 4 on plate and pH 8.6, μ =
NIH-PA Author ManuscriptNIH-PA Author Manuscript NIH-PA Author Manuscript 0.1 in buffer tank). Agar plates charged with antiserum were incubated in a humid chamber at 37°C for 24 hours and stained with amido black.
ResultsThe Hp type of both the donors and recipients was 2-2 in Cases 1 and 4. In Case 1, the same type was present after transplantation in samples obtained on post-operative days 10, 52, and 102. Patient 4 was studied 6, 12, 40, and 58 hours posttransplantation and after 4 and 6 days. During the first 12 hours, there was a 2-1 Hp type mixed with t...