Characterization of the nicotinic acetylcholine receptor antibodies after an unexpected increase of antibody titer in thymoma associated myasthenia gravis patients

Published:August 10, 2022DOI:


      • Anti-nAChR autoAbs titer increased in sera of two TMG patients with stable symptoms.
      • The titer's increase correlated with an increase of non-anti-α1 autoAbs.
      • Immunotherapy modification when non-anti-α1 autoAbs increase might not be needed.


      Two thymoma-associated myasthenia gravis patients with chronic well-controlled disease but an unexpected increase in anti-nAChR autoantibodies titer are reported. The specificity of anti-nAChR autoantibodies directed against extracellular parts of the receptor was studied in order to investigate the discrepancy between clinical and immunological status. Analysis of the anti-nAChR autoantibodies recognizing the extracellular parts of the nAChR revealed that when the concentration of anti-nAChR autoantibodies titer increased both patients had non-anti-α1 autoantibodies. Since the clinical profile of both patients remained unchanged, the increase of non-anti-α1 autoantibodies did not affect the 2 patients’ disease progression. Thus, immunotherapy modification due to an increase of anti-nAChR autoantibodies titer could be erroneous and potentially harmful.


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