Antibodies against human neuroblastoma cells in the sera of patients with myasthenia gravis.

The autoimmune nature of acquired myasthenia gravis is well documented. Although anti-acetylcholine receptor antibodies are pathognomonic for this disease, their significance in the immunopathogenesis of myasthenia gravis may differ among patients. The presence of antibodies against human neuroblastoma cells in myasthenic sera was studied using the 125I-labelled protein-A radioimmunoassay and indirect immunofluorescence. For comparison sera of patients with other neurological diseases were examined. Significant levels of antibodies against neuroblastoma cells were found in the sera of over 60% of myasthenia gravis patients and in some patients of the other disease groups, but mainly in lower titers. Our findings suggests a more generalized neuroimmunological abnormality in some myasthenia gravis patients.