398 THE BACTERIOPHAGE AND ITS BEHAVIOR 



process of bacteriophagy. The bacteriophage protobes utilize one 

 fraction of the bacterium for their development, and this part is neces- 

 sarily transformed since, as we have seen, bacteriophage substance differs 

 from bacterium substance, but apparently the rest is not modified 

 chemically, since its antigenic properties are the same after bacterio- 

 phagy as they were before. Otto and Winkler*^^ saturated an anti- 

 bacteriophagic serum with the homologous bacterium and found that 

 the antibacterial properties disappeared. Nevertheless, despite the 

 fact that the bacterial antibodies were absorbed, the antibacteriophagic 

 property persisted. From this they concluded that the bacteriophage 

 possesses an antigenic function of its own. 



Does the antibacteriophagic serum contain antibodies for the "prod- 

 ucts resulting from bacteriophagy"? It is impossible to say. 



As for the presence of antibodies for the physiological products 

 elaborated by the bacteria before they undergo dissolution, we will 

 shortly see what happens. 



8. THE ANTI-ANTIBACTERIOPHAGIC SERUM 



In connection with the bacteriophage, as with so many other im- 

 munological studies, we have the question of anti-antibodies receiving 

 attention. Fabry and van Beneden^^^ first prepared an antibacterio- 

 phagic serum in a rabbit by a series of injections of a bacteriophage 

 suspension, the serum being collected when the antibacteriophagic 

 property was sufficiently outspoken. They then immunized a dog 

 with this antiserum, first injecting the serum subcutaneously, later 

 intraperitoneally, in amounts of 1 to 2 cc. Two rabbits and three 

 guinea pigs were also injected with the same antiserum. After 5 

 injections, given at 4 day intervals, they allowed the animals to remain 

 without further treatment for a month, in order that the passively 

 transferred immunity might disappear. The animals were then bled. 



In the case of the rabbits and the guinea pigs they were unable to 

 find the sHghtest evidence of an anti-antibacteriophagic property. 

 With the dog serum, on the contrary, some interesting observations 

 were made. A mixture of equal parts of the antibacteriophagic serum 

 and of that of the dog immunized with this antiserum was incubated 

 for an hour at 37°C., and then allowed to stand over night at laboratory 

 temperature. With this incubated mixture of the two sera the follow- 

 ing tests were made. 



Each of 12 tubes, containing 10 cc. of bouillon, was seeded with a 

 drop of a culture of B. coli. To these implanted tubes, the various 



