Production of anti-idiotypic antibodies as potential immunoreagents for the serological diagnosis of bovine cysticercosis.

Although serological assays have been developed for cysticercosis, difficulties remain in isolating antigens from cross-reacting components and in obtaining reliable sources of parasite material for purification. The object of this study was to demonstrate the feasibility of using anti-idiotypic antibodies as alternative immunoreagents for the serological diagnosis of bovine cysticercosis. A fraction of Taenia hydatigena cyst fluid (ThFAS) had previously been used as a diagnostic antigen for Taenia saginata cysticercosis. Rabbits and mice were inoculated with ThFAS to produce either polyclonal or monoclonal antibodies (idiotypes), respectively. Idiotypes were purified by preparative protein A column, then inoculated into other rabbits to produce anti-idiotypes. The presence of anti-idiotypes in hyperimmune serum was demonstrated by competitive inhibition ELISA. Then anti-idiotypes were purified and used as coating antigen in a plate ELISA; results were compared to those using ThFAS as coating antigen. Anti-idiotypes yielded results comparable to those obtained with the native antigen and thus can be used as synthetic antigens for diagnostic purposes.