84 IMMUNE SERA 



Diverging Views of Ehrlich and Bordet. Now if 



we recall the first experiments of Bordet and his 

 conclusions respecting the manner in which the 

 factors concerned a^.ted, we shall at once see how 

 Ehrlich and Bordet differ. Bordet assumes that 

 the substance sensibilatrice (the immune body) 

 acts as a kind of mordant on the red cells or bac- 

 teria, sensitizing these to the action of the alexin 

 (complement). That is to say, neither the cell nor 

 the immune body has alone any manifest affinity 

 for the alexin, but they form by their union a 

 complex which can absorb alexin, in other words 

 which has particular properties of adhesion. Accord- 

 ing to Bordet, then, there is no such thing as an 

 amboceptor, and no complementophile group. He 

 cites the experiments of Muir as showing that the 

 hypothesis of a complementophile group is untenable. 

 This author found that blood corpuscles which had 

 fixed the sensitizer (immune body) and had been 

 saturated with alexin could subsequently, by dif- 

 fusion, lose a certain amount of their sensitizer, 

 although they retain the alexin, and what is more 

 in this instance they lose as much sensitizer as 

 if they had not absorbed alexin. Consequently, 

 says Bordet, it is in no way through the media- 

 tion of the sensitizer that the alexin attaches 

 itself to the corpuscles; if this were the case the 

 removal of the sensitizer would necessarily imply 

 that of the alexin (complement), which, as we 



