STUDIES ON MMOLYSINS. 89 



formed through immunization, corresponding to the multiplicity of 

 the complements present in the serum, are exceedingly manifold. 



Especially significant, however, is the fact that the cells possess 

 a great number of different kinds of groups, which groups can lead 

 to the production of numerous different amboceptors (immune 

 bodies). 1 



Hence in immunzing an animal with cell material, the organism 

 is injected, not with a single uniform substance, but with a multitude 

 of the most varied receptors, each of which is more or less able to 

 produce an antibody. In our fourth communication we defined our 

 point of view on this basis as follows: 



"In view of our experiments on isolysins described in our third 

 communication the occurrence of different immune bodies in a 

 hsemolytic serum obtained by immunizing with red blood-cells is 

 not at all surprising. We have obtained a whole series of different 

 isolysins by injecting goats with goat-blood. At present they number 

 twelve. In the red blood-cells not merely a single group, but a large 

 number of different groups, must be considered, which, provided 

 there are fitting receptors, can produce a corresponding series of 

 immune bodies. All of these immune bodies, again, will be anchored 

 by the blood-cells employed in immunization. We may assume 

 that when an animal, species A, is immunized with blood-cells of 

 species B, a hsemolytic serum will be produced which contains a great 

 host of immune bodies. The immune bodies in their entirety are 

 anchored by the blood-cells of species A." 



Durham 2 has adopted the same view for the bacterioagglutinins. 

 He assumes a number of " components " (corresponding to our recep- 

 tors) in the body substance of the bacteria, which can cause the 

 production of a corresponding number of agglutinins. In this way 

 each agglutinin which acts on a certain species of bacteria represents 

 the sum of different kinds of single agglutinins, a view entirely 

 analogous to our assumption of a plurality of immune bodies. This 

 view permits Durham to offer a sufficient and natural explanation 

 of the varying degree of action of typhoid agglutinins on typhiod 

 bacilli of different origin, and of the extension of the agglutinating 

 action of specific sera to related species of bacteria. It would be 



1 Compare the thorough exposition by Ehrlich in Vol. VIII of Nothnagel's 

 Specielle Pathologie und Therapie, Holder, Vienna, 1901. 



1 Durham, Journ. of Experimental Medicine, New York, Vol. V, No. 4, 1901. 



