ABSTRACT
In this chapter, the authors suggest that the SSS sequence is the molecular basis of the anti-PGLl epibody. They show that the anti-PGLl antibodies reacted specifically with the Glo light chains, but neither with the heavy chain of Glo nor with the light chains of pooled human IgG. The component has epibody properties and reacts with the RF Glo, non-RF Dau, and human IgG, but not with the non-RF Ch paraprotein. However, since cl47 reacts with various RFs that have quite different light chain variable regions, "conformational mimicry" may also contribute to its epibody activity. The experiments also indicate that there are three components in the anti-PGLl antiserum: conventional anti-Id that react with Glo light chains only, and whose antibody reactivity is completely inhibited by PGL1. Epibodies that react with both Glo light chain and IgG, and whose antibody reactivity is inhibitable by PGL1; and anti-IgG antibodies that react with IgG only, and whose binding is not inhibited by PGL1.
