BACTERICIDAL PROPERTIES OF BLOOD SERUM 151 



immunized with ox blood, the resulting antiserum is capable of pro- 

 ducing hemolysis not only of ox blood but of goat's blood as well, 

 though to a lesser degree. They conclude from this that the hemo- 

 lytic action of the serum must be referred to the presence of at least 

 two kinds of amboceptor, especially since repeated experiments with 

 different anti-ox-blood sera showed that there was no regularity in 

 the proportions of hemolysins for ox and goat blood, respectively. 

 This opinion they further fortify by showing that exposure of the 

 serum to ox blood deprives it of all its hemolysins, both those for 

 ox and those for goat's blood, whereas absorption with goat's blood 

 alone removes the specific goat's blood hemolysins only. They trans- 

 late their understanding of the conditions to graphic form by the 

 following diagram: 38 



If ox blood is in- _ 

 jected, a and ft receptors 

 being present, and ft 

 amboceptors are formed, 

 and ox blood can conse- 

 quently anchor both am- 

 boceptors. The presence 

 of ft receptors in goat's 

 blood also explains the 

 moderate hemolysis of 



OX 



GOtfT 



SCHEMATIC EEPRESENTATION OF EHRLICH AND 

 MORGENROTH'S CONCEPTION OF THE COMPLEX 

 STRUCTURE OF AN ANTIGEN. 

 (After Ehrlich and Morgenroth. Berl. Tdln. 

 Woch., Vol. 38, 1901.) 



this blood by the anti- 

 serum, but lacking the 

 receptors which, in this 

 case, represent the larger 

 proportion, these blood 

 cells cannot remove all 

 the amboceptor for ox 

 blood out of the serum. 

 The example given, of 



course, represents the simplest assumed case, and Ehrlich and Mor- 

 genroth believe that the same blood or bacterial cells may possess an 

 entire series of such receptors, some of them being dominant for the 

 given species, others being merely secondary or "partial," in varying 

 proportions. 



If we grant the fundamental premises of Ehrlich respecting the 

 "double receptor" or "amboceptor" nature of the specific antibody 

 and its mediation between antigen and complement by means of a 

 cytophile and a complementophile receptor, certain logical conse- 

 quences of this conception suggest themselves, which, in their many 

 ramifications, have been the subject of much investigation. And 

 although many phases of these researches are no longer commonly 

 accepted, some, indeed, being untenable in the light of more recent 

 38 Ehrlich. "Gesammelte Arbeiten," p. 147. 



