Analysis of binding curves in multivalent antigen-heterogeneous antibody response

The binding of antibodies to N-valent antigens can be utilized to gain information on the antibody affinity distribution, under the assumption, that the formation of each bond occurs as an independent event. The analysis of the most widely used plots of binding data (double reciprocal, Scatchard, Sips and the so-called “avidity” plot) leads to expressions which correlate asymptotical features of the binding curves to the antibody site concentration to the antigen valence and to the affinity moments <K−1>, <K> and <K2>. Only in the “avidity” plot is the shape of the curve independent of the valence of the antigen, depending merely on the antibody affinity distribution.