Anti-CD30 (Ber-H2) epitope requires structural elements as shown by mass spectroscopy and dual-site associated kinetics.

Abstract

The Ber-H2 mouse monoclonal antibody has been in use for thirty-five years for detecting the CD-30 biomarker in a variety of lymphomas. Despite the wide use of this clone, we have not been successful in applying synthetic peptides derived from the published epitope sequence and affinity data towards the development of a new Ber-H2-based in-vitro diagnostic reagent (IVDR) assay. We found that synthetic peptides based on the published epitope sequence do not function to inhibit antibody-binding activity, thus indicating that the sequence is not the full epitope recognized by Ber-H2. In this report, we used mass spectroscopic analysis of proteolysed CD30 fragments capable of binding Ber-H2 to identify additional regions within the epitope that participate in binding. Using surface plasmon resonance binding kinetic analyses and immuno-histochemical peptide-inhibition assays, we also demonstrate that the epitope sequence as originally reported is missing two key elements necessary for binding the Ber-H2 antibody. This article is protected by copyright. All rights reserved.