BACTERICIDAL PROPERTIES OF BLOOD SERUM 153 



COMPLEMENT 



for ox blood (derived from different animals), they concluded that 

 these "amboceptor" must possess different "cytophile groups." 



That this conclusion of Ehrlich and Morgenroth is not correct 

 seems to follow the subsequent work of Bordet. 40 He demonstrated 

 that it is not necessary to inject animals with specific hemolytic sera 

 in order to obtain antilytic sera, but that the same object may be 

 attained by injecting animals with the normal serum of an un- 

 treated animal. Moreover, if an "antisensitizing" serum so pro- 

 duced was added to corpuscles which had al- 

 ready absorbed "amboceptor," it prevented the 

 subsequent union of these sensitized cells with 

 alexin or complement. From this it becomes 

 clear that, in the first place, the antisensitizer 

 or anti-amboceptor cannot be identical with the 

 cell receptors of the corpuscles, and, further, 

 that the inhibition of the hemolysis which such 

 an antisensitizer exerts, cannot be due to union 

 Avith the "cytophile" group. This both contra- 

 dicts the Ehrlich conception of the mechanism 

 of "anti-amboceptors" and invalidates his ar- 

 gument, in this instance, in favor of the plural- 

 ity of the amboceptors produced by the injec- 

 tion. 



Bordet's experiments were later confirmed 

 by Ehrlich and Sachs, 41 who admit the error 

 of the former "anticytophile" interpretation 

 of Ehrlich and Morgenroth's experiments, but 

 they still maintain that Bordet's experiments 

 do not disprove the conception of an "ambo- 

 ceptor" or "Zwischenkorper" of Ehrlich. They 

 claim that Bordet's results merely prove that 

 the anti-amboceptor or anti-sensitizer is "anticomplementophile" in- 

 stead of "anticytophile." 



The principles involved we will discuss in another place in con- 

 nection with Moreschi's analysis of the "anticomplements." How- 

 ever this may be, we may conclude that Ehrlich and Morgenroth's 

 differentiation of amboceptors or sensitizers by the cytophile group 

 is no longer valid. 



The studies of Bordet on the antisensitizers (anti-amboceptor) 

 had important results apart from their refutation of Ehrlich and 

 Morgenroth's opinion. In addition to showing that such antisensi- 

 tizer did not represent cell receptors identical with those that an- 

 chored the sensitizer (amboceptor) to the red blood cells, his experi- 

 ments revealed the fact that such an antisensitizer neutralizes un- 



40 Bordet. Ann. de I'Inst. Past., Vol. 18, 1904, p. 593. 



41 Ehrlich and Sachs. Berl klin. Woch., No. 19, 1905. 



flNriAVBOCEPTOR 



SCHEMATIC REPRESEN- 

 TATION OF EHRLICH 

 AND MORGENROTH 's 

 CONCEPTION OF THE 

 NEUTRALIZATION OF 

 A HEMOLYTIC 

 SERUM BY ANTILY- 

 SIN OR ANTIAMBO- 

 CEPTOR, REACTING 

 WITH THE CYTO- 

 PHILE GROUP. (Ehr- 

 lich and Morgenroth, 

 loc. cit.) 



This conception, as we 

 shall see, has be- 

 come untenable. 



