Determination of the Antibody Activity of CSF Oligoclonal Bands by Immunoblotting

Abstract

The occurrence of oligoclonal bands in cerebrospinal fluid (CSF) from patients with chronic inflammatory disorders of the central nervous system (CNS) is well known. In infectious diseases, most of these bands are IgG antibodies directed against antigenic determinants of the causative agent. The identification of the antibody specificity of such oligoclonal IgG bands, which are synthesized intrathecally, is obviously clinically relevant. Recently, Dorries and Ter Meulen (1) described an immunoblot technique for the detection of virus-specific oligoclonal IgG in unconcentrated CSF. We also used the same technique based on an immunoaffinity transfer onto nitrocellulose sheets after isoelectric focusing of CSF proteins. In addition, we studied the occurrence of IgA oligoclonal bands and succeeded in reducing backgrounds by the use of soluble (and not insolubilized) infectious antigens and of a second biotinylated antiserum of hyperimmunized animals. CSF samples from patients with neurobrucellosis and herpetic encephalitis were especially studied.