110 



APPLIED IMMUNOLOGY 



mixed by inversion, the tubes are placed in the incu- 

 bator for one hour at 37° C After this time, if the 

 amboceptor is sufficiently powerful for practical use, 

 the corpuscles in the tubes containing 1-500, 1-1000, 

 1-1500, and 1-2000 dilutions of rabbit's serum should 

 be completely hasmolyzed. Those in the tubes con- 

 taining higher dilutions generally show partial hsemol- 

 ysis. The following table illustrates the titration of 

 haemolytic amboceptor: 



Amboceptor 



dilution 



1-500 



1-1000 



1-1500 



1-2000 



1-3000 



1 1-4000 

 1 1-5000 



Comple- 

 ment 



0.1 

 0.1 

 0.1 

 0.1 

 0.1 



0.1 

 0.1 



Result 



Complete hsemolysis 

 Complete liEemolysis 

 Complete haemolysis 

 Complete hsemolysis 

 Almost complete 



hsemolysis 

 Partial hsemolysis 

 Partial hsemolysis 



If the 1-2000 tube does not show complete haemol- 

 ysis, the rabbit must be given another injection of 

 sheep's corpuscles in order to raise the hsemolytic 

 power of the serum. If the serum is found to be of 

 sufficient hsemolytic strength, the rabbit should be 

 etherized and bled to death from the carotid artery 

 ' without delay, as the serum in the living animal will 

 lose its hsemolytic power after a time. The rabbit's 

 blood is collected in Petri dishes, and set aside on ice 

 imtil the clear serum separates. This is drawn oif 



