Subtypes of antimitochondrial antibodies in primary biliary cirrhosis before and after orthotopic liver transplantation

Abstract

Antimitochondrial antibodies are markers for primary biliary cirrhosis and probably reflect a specific defect in immunoregulation underlying this disease. Antimitochondrial antibodies and their primary biliary cirrhosis-specific subtypes were tested before and up to 6 years after orthotopic liver transplantation. Sera from 31 consecutive patients were tested, 15 patients had primary biliary cirrhosis and 16 non-primary biliary cirrhosis. Antimitochondrial antibodies were investigated under code by immunofluorescence, and primary biliary cirrhosis-specific subtypes were determined by radioimmunoassay (anti-p62, anti-p48) and complement fixation test (anti-M2, anti-M4, anti-M8). Before orthotopic liver transplantation, antimitochondrial antibodies were detected by immunofluorescence in 13 of 15 patients with primary biliary cirrhosis. Of these patients, 12 were positive for anti-p62 and 8 for anti-p48. Ten patients were positive for anti-M2, 4 patients for anti-M4 and 7 patients for anti-M8. Two primary biliary cirrhosis patients and all non-primary biliary cirrhosis patients were negative with all tests. One month after orthotopic liver transplantation, antimitochondrial antibodies titers declined or became negative by antimitochondrial antibodies immunofluorescence, 3 patients became negative by radioimmunoassay for anti-p62 and 1 for anti-p48. With complement fixation test, 4 patients became negative for anti-M2, 2 for anti-M4 and 4 for anti-M8. Antimitochondrial antibody titer reduction observed 1 month after orthotopic liver transplantation remained unchanged in most sera during the following years. A rise was observed in two patients after 4 and 5 years. We conclude that antimitochondrial antibodies titers detected by immunofluorescence and their primary biliary cirrhosis-specific subtypes decline after orthotopic liver transplantation or become negative. Subtypes after orthotopic liver transplantation are the same as before. Antimitochondrial antibody titer height does not influence long-term results. A recurrence of primary biliary cirrhosis was not observed in our primary biliary cirrhosis patients after orthotopic liver transplantation. Disappearance of antimitochondrial antibodies may be either due to prednisolone treatment or to a cure of the disease by orthotopic liver transplantation.