Idiotypy of measles virus nucleocapsid-specific IgGkappa antibody in serum and cerebrospinal fluid in subacute sclerosing panencephalitis.

A gel-precipitating anti-idiotypic antiserum was prepared in a rabbit by immunization with measles virus-specific IgG isolated from the serum of a patient with subacute sclerosing pancencephalitis (SSPE). The idiotypic determinant was associated with an electrophoretically restricted and cathodally migrating IgGkappa protein in serum and cerebrospinal fluid (CSF) with antibody activity to measles nucleocapsids. The anti-idiotypic antiserum did not precipitate with other oligoclonal populations of measles-specific IgG in the patients serum or CSF, nor with serum or CSF from 4 other patients with SSPE and 10 patients with multiple sclerosis.