[Laurell electroimmunodiffusion. Concerns and limits of various technics for the study of immunoaffinity...

Monodimensional and bidimensional electroimmunodifusion techniques were applied to the study of immunochromatography eluates. They were obtained with human sera as samples, and rabbit anti human sera alpha1AGP antibodies coupled to CNBr Sepharose 4B packed in a chromatography column. By monodimensional electroimmunodiffusion alpha1AGP could be quantitated. By tandem bidimensional immunoelectrophoresis the eluate purity could be shown, as well as its identity to alpha1AGP. Besides, this last technique was used to the critical study of elution conditions, and to put forward the influence of some parameters (such as pH ionic strength) on alpha1AGP denaturation and its transformation into a protein which is still antigenic but has lost a part of its electrophoretic mobility at pH 8.6. This phenomenon could explain the alpha1AGP loss observed after column elution. The precautions in the interpretation, the interest and the sensitiveness of the electroimmunodiffusion techniques are exposed.