940 EXPERIMENTAL INFECTION AND IMMUNITY 



EXERCISE 52. CYTOTOXINS 

 EXPERIMENT 105. ACTION OF NEPHROTOXIN 



1. Prepare an emulsion of dog kidney as described on page 74 and immunize 

 a rabbit. 



2. Inject a dog intravenously with 2 c.c. of rabbit immune serum per kilo of body 

 weight. 



3. Place the animal in a metabolism cage, collect all urine, and carefully examine 

 for albumin, casts, and hemoglobin; make quantitative albumin determinations. 



4. After three days autopsy and examine the kidneys and liver histologically. 



5. Heat the immune serum to 56 C. for thirty minutes and place increasing 

 amounts in a series of test-tubes as follows: 0.01, 0.05, 0.08, 0.1, and 0.2 c.c.; add 

 1 c.c. of fresh guinea-pig complement serum 1 : 20, and 1 c.c. of 2J^ per cent, suspension 

 of washed dog erythrocytes. Incubate for two hours. 



(a) Describe the changes occurring in the liver and kidneys. Give 

 the prevailing views regarding the mechanism of their production. 



(b) Are there any evidences of a hemolytic action of the serum in 

 vivo? In vitro? 



(c) How do you explain the presence o. f hemolysin in this immune 

 serum? 



(d) Discuss the specificity of cytotoxins in general. 



(e) How may a hemolysin be removed from a nephrocytotoxic 

 serum? 



(f ) Have the cytotoxins any practical value in the treatment of dis- 

 ease? 



EXERCISE 53. MIOST AGMIN REACTION 

 EXPERIMENT 106. TECHNIC OF THE MIOSTAGMIN REACTION 



1. Secure a portion of dry pulverized cancer tissue and prepare an antigen after 

 the technic described in the text. 



2. Titrate this antigen. 



3. Secure four specimens of serum: one from a known case of cancer; one from 

 a normal person, and two for diagnosis. 



4. Proceed with the reaction as described in the text. 



(a) Discuss the principles of this reaction. 



(b) Discuss the practical value of this reaction in the diagnosis of 

 cancer. 



EXERCISE 54. ANAPHYLAXIS 



For experiments in anaphylaxis sensitize a series of animals as follows : 

 (a) Give seven young guinea-pigs an intraperitoneal injection of 0.01 

 c.c. horse serum (1 c.c. of a 1 : 100 dilution). 



