Idiotypic network in myasthenia gravis demonstrated by human monoclonal B-cell lines

Human monoclonal anti-receptor and anti-idiotypic antibodies were obtained from Epstein-Barr virus-transformed lymphoblastoid cells of patients with myasthenia gravis. The majority of antibodies (85/117) were IgM, and all IgM antibodies had lambda light chains. A marked restriction to one recurrent idiotype was found, despite the additional presence of other idiotypes in the serum from all patients. The presence of idiotypes and anti-idiotypes in the same patient was verified by the demonstration of specific complex formation between an anti-receptor antibody and an anti-idiotypic antibody produced by two different clones. Studies of human monoclonal antibodies produced by lymphoblastoid cell lines provide important information about the B-cell repertoire in myasthenia gravis and demonstrate a basis for a functional antibody network in this disease.