Aggressin-like Action of Anaphylatoxin. 75 



the emulsion to remain in the incubator for 6 hours. At the end 

 of this time centrifugation for one to two hours at high speed was 

 used to throw down the bacteria. 



Although the supernatant fluid after such centrifugation was 

 clear, nevertheless it appeared in many cases that not all the 

 bacteria were thrown down. Intraperitoneal injection of the 

 anaphylatoxin occasionally resulted in the rapid death of the 

 guinea-pigs with extensive proliferation of typhoid bacilli in the 

 peritoneal exudate and presence of the organisms in the heart's 

 blood . 



Since the lethal dose of the typhoid culture employed varied 

 between 1/10 and 1/50 of an agar slant (for guinea-pigs of about 

 200 grammes on intraperitoneal injection) and since the amounts 

 of bacteria injected with 2 to 3 c.c. of an apparently clear anaphyla- 

 toxin could not have been anything like as much as the smallest 

 lethal dose, special experiments were carried out to determine this 

 point. An example of such experiments is the following: 



Experiment 2, 9, 14. 

 Anaphylatoxin prepared in the ordinary way, — centrifugalized for over one hour 

 until supernatant fluid appears absolutely clear. Cultivation experiments from this 

 fluid show, however, that it is not absolutely sterile, — a few colonies resulting from 

 a planting of several loopfuls. 



Experiment 



Dose Intraperitoneal injection 



Typhoid 

 Control culture 



No. 1 



1/10 



+ , 



3 c.c. 



salt solution 





death in 52 hrs. 



2 



1/20 



+ 



3 c.c. 



salt solution 





death in 18 hrs. 



3 



1 /SO 



+ 



3 c.c. 



salt solution 





remains alive 



Experim 



ent 













I 



1/100 



+ 



3 c.c. 



anaphylatoxin 





death in 22 hrs. 



2 



1/100 



+ 



3 c.c. 



anaphylatoxin 





death in 18 hrs. 



3 



1/200 



+ 



3 c.c. 



anaphylatoxin 





death in 18 hrs. 



4 



1/200 



+ 



3 c.c. 



anaphylatoxin 





death in 35 hrs. 



5 



1/200 



+ 



3 c.c. 



anaphylatoxin 





death in 35 hrs. 



6 



1/300 



+ 



3 c.c. 



anaphylatoxin 





remains alive 



A number of similar experiments were made in all of which it 

 was found that 1/200 to 1/300 of a typhoid culture combined 

 with 2 to 3 c.c. of anaphylatoxin would bring about the rapid 

 death of a guinea-pig by typhoid infection within a short time, 

 when 1/50 of a culture alone, and in some cases as much as 1/20 

 and 1/10 of a culture alone, did not kill. 3 c.c. of anaphylatoxin 



