Anti-idiotypic antibodies as immunogens: idiotype-based vaccines

Numerous studies have documented that antibodies may regulate the immune system and form the basis of vaccines, namely anti-idiotype vaccines. Antibodies carry individual idiotype antigenic determinants against which antibodies can be formed. When the anti-idiotype recognizes the same site that recognizes the primary antigen, a mirror image or combining site antibody may be generated. Other anti-idiotypes which recognize non-combining antigenic determinants have also been used. The evidence is reviewed for the existence of a broad range of anti-idiotypes and details are given of how an anti-idiotype vaccine based on the hepatitis B surface antigen has protected against virus challenge in the most relevant animal model system, namely the chimpanzee. Furthermore, the definition of the CD4 molecule as the conserved binding site for all known human and similar immunodeficiency viruses, (in marked contradiction to their varied neutralizing properties) has led to the raising of anti-idiotypes in mice based on the CD4 receptor which have the capacity to neutralize a broad range of isolates.