ANTI-ALPHA-TUBULIN AND BETA-TUBULIN IGM ANTIBODIES IN DYSIMMUNE NEUROPATHIES

An increased frequency of serum IgM antibodies to beta-tubulin has bee n found by ELISA in patients with chronic inflammatory demyelinating p olyneuropathy (CIDP) and the Guillain-Barne syndrome (GBS). We used an immunoblot technique to compare the frequency, titer and specificity of anti-tubulin IgM antibodies in 207 patients with different neuropat hies, 109 with other neurological disease (OND) and 110 non-neurologic al controls. High titers of serum anti-tubulin IgM antibodies (> 1:160 0) were present in 2 patients with CIDP(10.5%), 1 with multifocal moto r neuropathy (MMN) (11%), 1 with GBS (1.8%), two with IgM monoclonal g ammopathy, one with (1.3%) and one without neuropathy (2.1%), and in t wo with OND (1.8%). Even if the relative binding to alpha- and beta-tu bulin differed among positive patients, in all IgM bound to both tubul in subunits. All positive patients had a similarly intense IgM reactiv ity with tubulin by ELISA that showed high anti-tubulin IgM in 4 addit ional CIDP patients (total positive by ELISA 30%) and in 7 of 23 norma l subjects (30%). Even if high anti-tubulin IgM were slightly more fre quent by immunoblot in chronic dysimmune neuropathies than in other di seases, possibly reflecting a secondary response to neural damage duri ng an ongoing immune response, their relatively low frequency in these diseases does not seem to justify their measurement for diagnostic ap plication.