Monoclonal Anti-Azobenzenearsonate Antibodies Expressing the Cross-reactive Idiotype: Immunochemical Studies Show that All Idiotypic Determinants Reside on a Single Molecule

Abstract

Cell lines that secreted antibodies to the hapten azobenzenearsonate (ABA) were established by hybridization of immune A/J [mouse] spleen cells to the non-secreting [mouse] myeloma NS-1 cells. Solid-phase radioimmunoassays (RIA) were developed for rapid screening of hybridoma supernatants to detect antibodies to ABA and to detect antibodies bearing the ABA cross-reactive idiotype (CRI). Hybrid clones secreting both CRI+ and CRI- anti-ABA antibodies were obtained. The supernatant from 1 clone (7-1-3) strongly inhibited binding of iodinated anti-idiotype serum in a competitive RIA. This clone expressing the CRI produced Ig of the IgG2a subclass. Solid-phase absorption of anti-idiotype serum followed by competitive radioimmunoassay analyses revealed that all the idiotypic determinants recognized by anti-idiotype serum reside on this monoclonal antibody.