20 COLLECTED STUDIES IN IMMUNITY. 



(1) The isolated destruction of single lysins by means of thermic 

 and chemic influences. 



(2) The binding of the different lysins by means of corresponding 

 species of blood, thus making their elective removal possible. With 

 red blood-cells this procedure, to which we shall return in a sub- 

 sequent article, offers many technical difficulties. On the other 

 hand, with a different kind of specific constituent of the serum, 

 namely, the agglutinins, this method is easily applied, as can be seen 

 by the experiments of Bordet l made in connection with our first 

 experiments and carried out by the methods employed by us. 



(3) A separation of the lysins also seems possible through im- 

 munization, by means of which one is able to obtain antibodies 

 against the normal lysins. Thus Kossel, Camus, and Gley, by treat- 

 ing animals with the strongly globulicidal eel serum, have obtained 

 a serum which neutralizes the action of this eel serum, in other words, 

 one containing an antilysin. Evidently this reactively formed anti- 

 body thrusts itself into the hsemotropic group of the interbody and 

 thus deflects this from the erythrocyte. Our attempts, based on 

 these premises, to produce an isolated antibody for some of the 

 lysins have thus far been unsuccessful. Thus a serum derived 

 from rabbits after these had been treated with goat serum, protected 

 the rabbit erythrocytes against solution by goat serum. At the same 

 time, however, it protected the blood of guinea-pigs and rats against 

 the same influence, and even prevented the hffimolytic action of dog 

 serum on rabbit blood. From this fact we must conclude that 

 immunization with one serum produces a whole series of different 

 antilysins. Clearly this is to be explained by assuming that a serum 

 contains a great number of different complexes possessing haptophore 

 groups, of which many, whether they are toxic or not, are able to 

 excite the production of corresponding antibodies. 



This surprising multiplicity of substances, present in the blood, 

 which possess haptophore groups (hsemolysins, agglutinins, ferments, 

 antiferments) is very readily harmonized with Ehrlich's views. 

 According to his conception all these substances represent side- 

 chains of the protoplasm, which have been thrust off and have reached 

 the circulation. The physiological object of the side-chains is, as 

 Ehrlich stated in 1885, 2 to bind assimilable substances to the 

 protoplasm so that these may serve as nutriment for the latter. 



1 Inst. Pasteur, March 1899. 



2 Ehrlich, Sauerstoffbedurfniss des Organismus. Berlin, 1885. 



