Oligoclonal IgA bands in multiple sclerosis and subacute sclerosing panencephalitis.

CSF oligoclonal IgG bands are often found in MS or cerebral diseases in which there is chronic antigenic stimulation. Using agarose isoelectric focusing followed by immunoblotting, we found oligoclonal IgA bands in CSF from 16 of 20 randomly selected patients with MS, 7 of 7 with subacute sclerosing panencephalitis (SSPE), and 0 of 10 with noninflammatory neurologic or psychiatric disease. IgA bands did not correlate with the course or stage of MS. Serial samples from two patients with MS and one with SSPE demonstrated only minor changes in IgA banding pattern. One MS patient without oligoclonal IgG bands had oligoclonal IgA bands, indicating that the latter test may be helpful in the diagnosis of MS.