328 METHODS OF IDENTIFICATION AND STUDY 



3. Wash with three changes of normal saline (vide 

 also page 388). 



4. Transfer the washed cells to a sterile capsule by 

 means of a sterile pipette. Add 5 c.c. of normal saline 

 and mix thoroughly. 



5. Take up the mixture of cells and saline in the all- 

 glass syringe and inject into the peritoneal cavity of the 

 rabbit. 



6. Seven days later inject intraperitoneally the 

 washed cells from 5 c.c. human blood mixed with 5 c.c. 

 normal saline. 



7. Seven days later inject the washed cells from 10 

 c.c. human blood mixed with 5 c.c. normal saline. 



8. After a further interval of seven days repeat the 

 injection of washed cells from 10 c.c. human blood 

 mixed with 5 c.c. normal saline. 



NOTE. Better results are obtained if the second and subsequent 

 injections are made intravenously, even when smaller quantities 

 of washed red cells are employed. If, however, the intravenous 

 route is selected exceeding great care must be exercised to avoid 

 the introduction of air into the vein an accident which is fol- 

 lowed, within a few minutes, by the death of the rabbit from 

 pulmonary embolism. 



9. Allow five days to elapse, then collect a prelimi- 

 nary sample of blood, say about 2 c.c., from the rabbit's 

 ear. Allow it to clot, separate off the serum and trans- 

 fer to a sterile test-tube. Place the test-tube in a 

 water-bath at 56 C. for fifteen minutes (to inactivate) 

 and test the serum quantitatively for haemolytic prop- 

 erties in the following manner: 



THE TITRATION OF HAEMOLYTIC SERUM. 



Apparatus Required, 

 Electrical centrifuge. 

 Sterile centrifuge tubes. 

 Water-bath regulated at 56 C. 

 Sterilised pipettes 10 c.c. graduated in tenths. 

 Sterilised pipettes i c.c. graduated in tenths. 



