Bence-Jones Proteins and Light Chains of Immunoglobulins

Abstract

Abstract The evaluation of numerous anti-κ chain antisera through immunochemical studies of κ light chains for which complete or partial sequence data were available has resulted in the localization of three distinct regions in the variant half of the light chain which are associated with specific antigenic sites. The residue at position 9 appears to be associated with an antigenic site which, in general, may be termed a group-related antigenic site. The residues at positions 45 and 94 through 96 are associated with two distinct antigenic sites which are recognized specifically by numerous antisera and are responsible for certain intergroup similarities and intragroup differences among κ chains. Many of the antisera readily distinguish among proteins which have been structurally assigned to the same subgroup. The localization of distinct regions which markedly influence the nature of the antigenicity of the light chain molecule provides a molecular basis for the observed heterogeneity among κ chains and contributes to the knowledge of the tertiary structure of the polypeptide chain.