56 LABORATORY COURSE IN SERUM STUDY 



A type protocol of such an experiment is given below: 



LESSON VIII 

 BACTERICIDAL TEST IN VITRO STERN KORTE 



THE destruction of bacteria which takes place in the peri- 

 toneum of immune animals may also be demonstrated for certain 

 species of bacteria in the test tube. Small quantities of typhoid 

 bacilli, as shown in a previous experiment, are killed by exposure to 

 certain normal sera such as those of the rabbit and the guinea pig. 

 A more powerful action is observed in sera of animals immunized 

 to the typhoid bacillus, and, as in the case of red cells, the immune 

 body or sensitizer can be shown to be relatively thermostable in 

 that it will act after exposure to 56 C. for half an hour provided it 

 is reactivated by the addition of a small amount of normal serum. 



The bactericidal effect of immune serum shows more clearly 

 than most other antibody phenomena the presence of a prezone, 



1 The bacteria may be measured for such an experiment by standard loop- 

 fuls (one loop being equal to 2 milligrams), or by volume in emulsion with salt 

 solution. 



