BACTERIOPHAGOUS ANTISERUM 131 



d. The products resulting from the activity of the bacterio- 

 phage, which we have grouped under the name of "lysins," and 

 which remain in the medium after the lytic process is completed. 



Does the bacteriophage attack the bacterium by means of a 

 single diastase or through a combination of diastases? At this 

 time it is impossible to say, and indeed, it would not materially 

 affect the question with which we are concerned. 



There is still another category of substances present in the 

 culture. We have seen that the bacteria do not remain passive 

 to the action of the bacteriophage, and that this defense is ac- 

 companied by the production of an anti-diastase an anti-lysin 

 which is likewise to be found in the medium. This should, then, 

 stimulate the formation of anti-anti-lysins. These have not 

 been investigated, and it is only sugested that they may possibly 

 be present in the serum of immunized animals. 



As an example of an antibacteriophagous serum we will take 

 the antibacteriophage-Shiga serum. This is particularly interest- 

 ing because of the potent endotoxin of the dysentery bacillus. 



A rabbit is injected with four doses of a culture of the anti- 

 dysentery bacteriophage 2 that is to say, of a lysed culture of B. 

 dysenteriae Shiga, amounting to two, four, six, and eight cubic 

 centimeters, with an interval of six days between each injection. 

 The rabbit is bled fifteen days after the last injection. Theoreti- 

 cally, the serum of this rabbit ought to contain the following anti- 

 bodies: 



a. Antibodies to the bacteria: Amboceptor and agglutinin. 



b. Antibody to the bacterial toxin: Antitoxin. 



c. Antibodies to the bacteriophagous ultramicrobe : Ambo- 

 ceptor and agglutinin. 



d. Antibody to the lytic diastase of the bacteriophage: Anti- 

 lysin. 



Let us see if the antibodies present in such a serum actually 

 correspond with those which theoretically should exist. 



2 As we will see in regard to barbone of the buffalo, the serum of an animal 

 which has received a single and minimal injection of a bacteriophage culture 

 does not present the antibacteriophagous property, or, at least, if it exists, 

 it is not detectable. 



