246 LECTURES ON IMMUNITY 



The experiments do not succeed if the passively immunised 

 animal is of the same species as that which has produced 

 the antitoxin. 



Probably the new antibody, the anti-antiricin, binds the 

 antiricin, just as ricin does, so that the antiricin becomes 

 divided between the ricin and the antibody ; and therefore 

 the ricin acts as if a less quantity of antiricin than that used 

 in the experiment had been employed. 



In the same manner it is possible by intravenous injec- 

 tion of a haemolysin (i.e. an antierythrocytic substance) to 

 produce corresponding antibodies. Thus, for instance, 

 after the injection of immune-body from the blood-serum 

 from a rabbit which had been actively immunised against 

 bovine erythrocytes into the veins of a guinea-pig, this 

 animal presented in its serum an anti-immune-body, specific 

 against the injected immune-body. Such experiments 

 were first carried out by Bordet, 1 who called the new 

 antibody " anti-sensibilisatrice." Nearly simultaneously 

 Ehrlich and Morgenroth 2 produced what they called 

 "anti-immune-bodies," and later on " anti-amboceptors." 

 Pfeiffer and Friedberger 3 prepared anti-immune-bodies 

 against cholera-serum from a goat, by injecting such 

 serum into the veins of a rabbit. 



Now, a compound haemolysin contains immune-body 

 and alexin and hasmolysin ; it may therefore seem possible 

 to obtain antibodies against these three different sub- 

 stances. To determine if the antibody be anti-immune- 



1 Bordet: Ann. de VInst. Pasteur, 14, 270 (1900). 



2 Ehrlich and Morgenroth: Berl. klin. Wochenschrift, No. 31 (1900); 

 Nos. 21 and 22 (1901). 



8 Pfeiffer and Friedberger : Berl. klin. Wochenschrift, No. I (1902). 



