Antigenicity of peptide 19-28 of toxin II from the scorpion Androctonus australis as measured by different solid-phase tests and characterization of specific antibodies purified by immunoaffinity on the peptide or the toxin.

The antigenicity of peptide 19-28, a model of one of the major antigenic regions of toxin II of the scorpion Androctonus australis Hector was tested in different solid phase radioimmunoassay systems. The type of the solid phase and the mode of binding the synthetic peptide to the phase had a considerable effect on the resulting antigenicity. Two subpopulations of anti-toxin II antibodies were purified by affinity chromatography, one on Sepharose-peptide 19-28, the other on sepharose-toxin. The native or chemically modified toxin bound in the same way to these subpopulations. Denatured toxin was only poorly recognized by these antibodies. This suggests that the antibodies purified on peptide 19-28 recognize the same conformation dependent antigenic surface as do total anti-toxin antibodies.