The antigenic characteristics and the significance of the adenine nucleotide translocator as a major autoantigen to antimitochondrial antibodies in dilated cardiomyopathy.

To obtain further knowledge of the antigen-antibody system, immunochemical characterization of the adenine nucleotide translocator was achieved by crossed immunoelectrophoresis, immunoreplica technique, radioimmunoassay, immunoabsorption studies, and nucleotide-transport measurements. Sera of 18 patients with proven congestive cardiomyopathy (CCM) were tested. On the adenine nucleotide translocator (ANT) from heart, kidney, and liver, organ-specific antigenic determinants were demonstrable, although a partial cross-reactivity existed. Conformation specificity was also confirmed by experimental studies. Of the patients studied, 17 of 18 with CCM showed a significant binding to the heart ANT, while no or a lower binding was seen on the kidney/liver ANT. In CCM, a correlation exists between the ejection fraction and the anti-ANT titer. These results give new evidence for autoimmunological events in MC and CCM and indicate a possible causal relationship between these two diseases.