CHAPTER XL 



SEROLOGICAL METHODS IN THE STUDY OF THE 



PROTOZOA 



By 



William H. Taliaferro 

 The University of Chicago 



introduction 



A. Limitation of the subject. Fundamentally, the science of 

 immunity in protozoan infections is concerned with the resistance 

 of the body to infection and disease. Following the general trend 

 of the development of the broader science, however, work with 

 the protozoa has, to a large extent, dealt with serological (test 

 tube) reactions because of their practical value. Although a great 

 deal of work has been carried out on the symptoms in the pro- 

 tozoan diseases, the production of toxin and toxin-antitoxin re- 

 actions, the hypersensitive states and anaphylaxis, cutaneous tests, 

 with especial reference to the detection of protozoan infections, 

 and the nature and artificial production of immunity, by far the 

 greatest amount of work has been focused on the serological 

 reactions. 



In the present review, therefore, attention will be limited to 

 the serological reactions — precipitation, agglutination, lysis, com- 

 plement fixation and certain miscellaneous reactions of the serum. 

 These will be considered from the standpoint of their use as test 

 tube reactions, and, where applicable, of the part they assume 

 in the defense of the body against infections with parasites. In 

 the latter case, their relation to the reproduction-inhibiting anti- 

 body, demonstrated in certain trypanosome infections, will be dis- 

 cussed. Since it would be impossible to review the mass of specific 

 investigations, attention will be particularly centered on tech- 

 nique and the more important investigations. For the general sub- 

 ject of immunology the reader is referred to the standard treatises 



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