862 EXPERIMENTAL INFECTION AND IMMUNITY 



EXERCISE 49. BACTERIOLYSIS 

 EXPERIMENT 101. PFEIFFER BACTERIOLYTIC TEST 



1. Secure 1 c.c. of serum from a rabbit which has been immunized with typhoid 

 bacilli. By working with cholera and a highly potent serum better results are secured, 

 but as there is probably more danger connected with the handling of cholera cultures, 

 typhoid may be substituted with fairly good results. Inactivate by heating to 56 

 C. for half an hour. 



2. Prepare a twenty-four-hour-old agar culture of a suitable strain of Bacillus 

 typhosus. 



3. Prepare a 1 : 100 dilution of the immune serum and place 3 c.c. in a small test- 

 tube. Add three loopfuls of culture and emulsify thoroughly. Inject a guinea-pig 

 intraperitoneally with 2 c.c. of the emulsion. 



4. At intervals of ten, twenty, forty, and sixty minutes withdraw small amounts 

 of exudate and study bacteriolysis; prepare hanging-drop preparations which may be 

 compared with a similar control on the culture; prepare smears of the culture and 

 peritoneal exudate and stain with carbol-thionin or carbolfuchsin. 



5. If desirable, the bacteriolytic titer of the serum may be determined after the 

 method given in the text. 



(a) Describe the phenomenon of bacteriolysis. 



(b) Are bacteriolysis and hemolysis similar processes? Give the 

 source of complement in this reaction. 



(c) Discuss the specificity of bacteriolytic reactions. 



(d) Discuss the practical value of the bacteriolytic test in the diag- 

 nosis of a microorganism. 



EXERCISE 50. BACTERIOLYSIS 



EXPERIMENT 102. MICROSCOPIC METHOD OF MEASURING THE BAC- 

 TERIOLYTIC POWER OF THE BLOOD 



This method may be employed for a rapid estimation of the bac- 

 teriolysin produced in the blood in response to an inoculation of typhoid 

 vaccine. 



1. Secure a small quantity of the patient's serum by collecting blood aseptically 

 in a Wright capsule. About 1 c.c. of serum will be sufficient. Secure a control 

 serum, preferably a "pooled serum," in the same manner. Prepare dilutions of the 

 patient's serum in the following manner: Place a series of six small test-tubes (sterile) 

 in a rack; add 1 c.c. sterile broth to each tube; into the first tube place 1 c.c. of the 

 fresh serum from the patient (1 : 2 dilution) ; mix well and transfer 1 c.c. to the second 

 tube; mix and transfer 1 c.c. to the third, and so on to the last tube, when 1 c.c. is 

 discarded. 



2. Secure a twenty-four-hour culture of typhoid bacilli in neutral bouillon. 



3. Take a simple capillary pipet with a long stem, plugged with cotton and steril- 

 ized, and make a mark about 3 cm. from the end. Draw up the highest dilution of 

 &erum to the pencil mark, then a bubble of air, and finally an equal volume of culture. 

 Thoroughly mix by carefully aspirating and driving out the contents on a hollow 



