200 INFECTION AND RESISTANCE 



fortunately, however, it was soon found by a number of workers, 

 Marie and Levaditi, 9 Weygant, Kraus and Yolk, Landsteiner, 

 Miiller, and Potzl, 10 and others that antigens perfectly capable of fix- 

 ing complement in the presence of syphilitic serum could be pro- 

 duced from normal organs. 11 



Theoretically it must be admitted that we are very much in the 

 dark at present. The fact, now entirely unquestionable, that the 

 sera of syphilitic patients will give fixation with antigens derived 

 from extracts of normal organs, as well as from those of syphilitic 

 organs, seems to throw doubt upon the simple specific antigen-anti- 

 body conception at first held. 



In order to understand the questions involved in the theories of 

 the Wassermann reaction as at present conceived it will be necessary 

 to consider the types of antigen which are now employed. 



Wassermann' s original method of antigen preparation consisted 

 in using the liver or spleen of a congenitally syphilitic fetus. The 

 organs were finely divided and emulsified in 4 to 6 parts of normal 

 salt solution. This mixture was shaken for 24 hours, centrifugal- 

 ized, and the clear supernatant fluid used as antigen. Later the 

 specific organ substances were extracted by Porges and Meier 12 in 

 five times the volume of absolute alcohol for 24 hours. This alco- 

 holic extract was evaporated in vacuo and the residue taken up in 

 salt solution and shaken until an even suspension resulted. 



After it had been discovered that normal organ extracts could 

 serve as antigen as well as the extracts of syphilitic organs, Land- 

 steiner, Porges and Meier, and others, introduced antigens produced 

 by alcoholic extraction of normal organs of animals and of man. 

 Landsteiner introduced the alcoholic extract of normal guinea pig 

 organs, especially extracts of the heart and liver, and Weil and 

 Braun 13 made use of extracts of normal human organs. There are 

 various methods of preparing extracts for this purpose. We may 

 mention, to illustrate these methods, the one suggested, first, we be- 

 lieve, by ^oguchi, a procedure which is applicable to the extraction 

 of normal human organs (spleen), beef hearts, and guinea pig hearts. 

 The finely divided or triturated organ substance is shaken up with 

 five times its weight of absolute alcohol and allowed to stand in the 



9 Marie and Levaditi. Cited from Mclntosh and Fildes' "Syphilis." 

 Longmans & Co., 1911, p. 94. 



10 Landsteiner, Muller, and Potzl. Wien. kl Woch., Vol. 20, 1907. 



11 An extensive historical review of the development of the Wassermann 

 reaction is found in the book of Boas, "Die Wassermannsche Reaktion," 

 Karger, Berlin, 1911. Since these earlier publications have appeared the 

 literature of the Wassermann reaction has become very extensive. It is 

 enumerated more fully than we can afford space for here in the book of 

 Noguchi ("Serum Diagnosis of Syphilis") and that of Boas, mentioned above. 



12 Porges and Meier. Berl. kl. Woch., No. 15, 1908. 



13 Weil and Braun. Berl. kl. Woch., No. 49, 1907. 



