High–titer selective serum anti–β–tubulin antibodies in chronic inflammatory demyelinating polyneuropathy

Although chronic inflammatory demyelinating polyneuropathy (CIDP) is presumed to be an autoimmune disorder, no neural antigen has been recognized as an immune target. We found that serum IgM from a patient with CIDP and an IgM paraprotein reacted with a 53-kd protein by Western blot analysis. Amino acid sequence analysis identified this protein as β-tubulin. We then studied sera from 70 CIDP patients, 35 Guillain-Barré syndrome (GBS) patients, and 483 disease (amyotrophic lateral sclerosis, Alzheimer's disease, multiple sclerosis, diabetes, and other polyneuropathies) and normal controls for selective high-titer anti-β-tubulin using ELISA methodology. Forty-two percent (30/70) of patients with CIDP had selective high titer IgM reactivity against β-tubulin; 23% (16/70) had selective high-titer IgG reactivity against β-tubulin. Overall, 57% of CIDP patients, 20% of GBS patients, and 2% of control patients had selective, high serum IgM or IgG anti-β-tubulin reactivity. Selective high-titer serum anti-β-tubulin antibodies occur in a majority of patients with CIDP but are rare in other chronic neuropathies or CNS disorders.