Anti-neuronal nicotinic receptor antibodies in MG patients with thymoma

We tested 24 MG patients with thymoma (11 invasive) for the presence of anti-neuronal nicotinic receptor subtype antibodies and found that none had antibodies against the ?7-containing subtype, and only one (with invasive thymoma) had antibodies directed against the ?3-containing subtype. In this patient, the anti-?3 antibodies recognized the extracellular part of the ?3 subunit. They developed later than the anti-?1 muscle antibodies, with their titer increasing during the illness, while that of the anti-?1 muscle antibody decreased. Our data suggest that there is no correlation between the presence of anti-?3 antibodies and thymoma. © 2001 Elsevier Science B.V.