404 THE BACTERIOPHAGE AND ITS BEHAVIOR 



When we immunize a rabbit with a suspenson of the bacteriophage, 

 along with the protobes we inject of necessity the materials resulting 

 from the dissolution of the bacterial bodies and also any toxins and 

 like substances that may be present. We should, therefore, necessarily 

 obtain a serum which at the same time will have antibacteriophagic, 

 antibacterial, and antitoxic properties. We have seen that this is 

 certainly true as regards the first two of these properties. In order to 

 demonstrate whether antitoxic principles are also present, carry out 

 the following experiment.^-^ 



Give a mouse, by subcutaneous injection, a lethal dose of a dysen- 

 tery toxin prepared by the method of Rowland, as modified by NicoUe,* 

 and at the same time, 0.5 cc. of the antiserum for the Shiga-bacterio- 

 phage. Give a second mouse the same quantity of toxin and 0.5 cc. 

 of an anti-Shiga serum. Give a third mouse a lethal dose of the toxin 

 only. Subsequent events shows that the first mouse dies in about 

 30 hours after the injection; the second mouse Hves indefinitely; and 

 the third dies 4 days after the injection. 



From this it is perfectly obvious that the antiserum for the Shiga- 

 bacteriophage is not antitoxic, indeed, on the contrary it seems to be 

 definitely sensitizing. Let us consider this singular phenomenon 

 somewhat further. 



Four mice receive subcutaneously a dose of dysentery toxin equal 

 to one-tenth of the lethal dose. The first mouse is held as a control 

 without further treatment. Two other mice receive in addition to 

 the toxin 0.2 cc. of the antiserum for the Shiga-bacteriophage, and the 

 last of the toxin-injected mice gets 0.1 cc. of the antiserum. The 

 results: The first remains perfectly well indefinitely, the two which 

 received the 0.2 cc. of dose of antiserum die after 40 hours, and the 

 last mouse dies after 54 hours. 



Here the results are even more clear-cut than in the previous ex- 

 periment; the Shiga-bacteriophage antiserum sensitizes the animals 

 to the action of the toxin. The results are the more striking when we 

 consider that whatever the number of lethal doses of the Nicolle Shiga 

 toxin injected into a mouse, death never occurs before the fourth day. 

 Here, when the antibacteriophagic serum is injected with the toxin, 

 even when added to a dose of toxin far below the normal minimal 

 lethal dose, death takes place within 48 hours. 



* The bacterial bodies are ground with anhydrous sodium sulfate, the powder 

 so obtained is dried in the air, and dissolved in water at the time of injection. 

 The turbid fluid thus obtained is centrifuged, and the clear supernatant portion 

 is used for the injection. 



