CHAPTER VIII 



PEACTICAL APPLICATIONS OF THE COMPLEMENT- 

 FIXATION METHOD 



THE WASSERMANN REACTION 



THE principle of specific alexin fixation has been practically 

 utilized in the diagnosis of disease and in the forensic determination 

 of the nature of spots of blood or other protein material. 



Soon after Bordet and Gengou's experiments Wassermann and 

 Bruck 1 showed that bacterial extracts could be successfully substi- 

 tuted for whole bacteria in these reactions. Citron, 2 too, made sim- 

 ilar observations, and, indeed, we now know that the use of bacterial 

 extracts is more suitable for these experiments than are emulsions 

 of whole bacteria, since, as we have mentioned above, bacterial emul- 

 sions may often fix small amounts of complement of themselves 

 (without specific sensitization), thereby confusing the results of the 

 reaction. 



On the basis of their experience with bacterial extracts Wasser- 

 mann and Bruck 3 then determined that complement fixation could 

 be carried out in tuberculosis when the various tuberculin prepara- 

 tions were used as antigen. 4 These investigations fell into the period 

 during which active research upon the Spirochoeta pallida in syphilis 

 was going on, and it occurred to Wassermann that the technique of 

 complement or alexin fixation might be utilized in the diagnosis of 

 syphilis. Together with Neisser and Bruck 5 he subjected this idea 

 to experimental test. The publication of their first results appeared 

 in 1906. They used in their experiments the syphilitic monkeys 

 which were being observed in Neisser's clinic. Their method con- 

 sisted in mixing inactivated serum from syphilis-inoculated monkeys 

 with organ extracts, serum, etc., of syphilitic human beings, and 



1 Wassermann and Bruck. M ed. Klinik, Vol. 55, 1905. 



2 Citron. Centralbl. f. Bakt., Vol. 41, 1906. 



3 Wassermann and Bruck. Deut. med. Woch., No. 12, 1906. 



4 Complement fixation in tuberculosis is not yet on a practical or reliable 

 basis. Recent claims of Besredka (Ann. Past., 1913) for his new antigen 

 promise a successful technique, but no extensive confirmation has followed up 

 to the present time. 



6 Wassermann, A. Neisser, and Bruck. Deut. med. Woch., No. 19, 1906. 



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