Further Studies on the Reactions of Diphtheria Toxoid with its Antisera by the Crossing Paper Electrophoresis

The distribution of antibodies in the dipththeria antisera was studied by the twodimensional crossing electrophoresis. Beside the two antibodies which had been found previously in the γ-grobulin zone to form very flat and broad peaks in the crossing diagram of toxoid, two other antibodies in γ-grobulin, which react with antigens contained in the main fraction of the toxoid, were found by the crossing electrophoresis. They were previously mistaken as being contained in β-grobulin. Two purified commercial antisera, one consiisting mainly of β-grobulin, and the other mainly of γ-grobulin, were studied of their antibody compositions. The number of antibodies demonstrated in these preparations were not significantly different from that in crude antiserum. Yet, the relative concentrations of individual antibdies diffrered considerably. The fact that they possess biologically nearly equivalent activity suggests that the toxic activity of the diphtheria toxin may not be ascribed to a single, but not a number of substances.