Identification of different measles virus-specific antibodies in the serum and cerebrospinal fluid from patients with subacute sclerosing pancencephalitis and multiple sclerosis.

Matched serum and cerebrospinal fluid (CSF) samples from eight cases of subacute sclerosing panencephalitis (SSPE) and 15 cases of multiple sclerosis (MS) were characterized in neutralization, hemolysis-inhibition (HLI), hemagglutination-inhibition (HI) with Tween 80-ether-treated antigen, complement-fixation (CF), and immunodiffusion tests. CF tests were carried out with crude virus material, purified nucleocapsids, and small particle hemagglutinin as antigens. A certain diversity in the relative content of antibodies against different virus products in various sera was found. There was a high degree of correlation between titers of neutralizing and HLI antibodies, but a less strict correlation between titers of HLI and HI antibodies. Serum samples from two cases of MS and one case of SSPE contained high titers of HLI and neutralizing antibodies in the presence of only low titers of HI antibodies demonstrable with Tween 80-ether-treated antigen. The major fraction of antibodies detected in CF and immunodiffusion tests reacted with nucleocapsids. There was a tendency of nucleocapsid CF antibody titers, as compared to neutralization and HLI antibody titers, to be higher in samples from patients with SSPE than from cases of MS. No significant differences were found between antibody titers recorded in neutralization, HLI, and HI tests carried out with two different measles virus strains, Edmonston and a strain (LEC) derived from a case of SSPE. Comparison of antibodies against measles virus products and, as a reference, against a group-specific vertex capsomer antigen of adenovirus in matched serum and CSF samples revealed a production of measles virus-specific antibodies within the central nervous system of all cases of SSPE and 8 out of 15 cases of MS.