THEORIES RELATING TO ANAPHYLAXIS 101 



We know, on the other hand, that rabbit's serum 

 thus prepared contains a precipitin in the presence 

 of horse serum. 



Now, Doerr and Russ have stated, without the 

 sHghtest reservation, that experiment with the ana- 

 phylactic antibody (sensibihsin) and the precipitating 

 antibody only forms one out of many experiments 

 that shew the existence of an entire parallelism 

 between these two substances.^ In another contri- 

 bution^ these workers have demonstrated that the 

 anaphylactic antigen (or sensibiligen) content of any 

 serum goes hand in hand with its precipitogen con- 

 tent. They have seen, moreover, that the anaphy- 

 lactic antibody appears and disappears in the serum 

 at exactly the same time as the precipitating anti- 

 body. 



In other words, in the opinion of Doerr and Russ, 

 these substances are incapable of dissociation in 

 serum. 



There are authors, however, who have thrown 

 doubt on the identity of these substances, and have 

 shewn that certain sera are capable of producing a 

 condition of anaphylaxis without exhibiting pre- 

 cipitation. 



Doerr and Moldovan^ made a vigorous reply to this 

 objection, remarking that the assumed lack of 

 parallelism only shewed defective technique on the 

 part of those who found these differences. Satis- 

 factory technique consisted, in the opinion of these 

 authors, in adding variable quantities of antiserum 

 to a fixed quantity of antigen. There were cases, 

 they said, in which the precipitate passed unnoticed 

 because it was redissolved in the excess of antigen. 

 But if only this technique were complied with to the 



1 Zeitschr. f. Immunitdtsf., I. Orig., iii., p. 706, 1909. 



2 Centralbl. f. Baki., I. Orig., lix., p. 73, 1911. 



3 Zeitschr. f. Immunitdtsf., I. Orig., v., p. i6i, 1910. 



