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INTRODUCTION TO IMMUNOCHEMICAL SPECIFICITY 



for the antibodies of an antiserum will be different for the different 

 antibodies ; combination of antigen or hapten will be firmer with some 

 than with others. Heterogeneity of antibody is responsible, for ex- 

 ample, for the fact that the relation between r/c and r, where r is the 

 average number of hapten molecules bound per antibody molecule 

 and c is the concentration of free hapten, is not a linear one (see Fig. 

 10-5). It was suggested by Pauling, Pressman, and Grossberg 

 (1944) that the standard free energy of combination of the various 

 antibody molecules may follow the distribution of the normal error 

 function (Gaussian distribution) (see Fig. 2-4). This suggestion has 

 been worked out in detail by Karush (Karush and Sonenberg, 

 1949; Karush, 1956). 



If Kq is the average binding constant and a a measure of the 



Fig. 10-5. Binding results at 25 °C. and 7.1 °C, for the reaction between D-Ip 

 hapten and purified anti-D-Ip antibody (Karush, 1957, 1958). The points are 

 experimental and the curves theoretical. 



