604 PATHOGENIC MICROORGANISMS 



in isolated cases reported by Uhlenhuth and Mulzer. Chemotherapy 

 has had results analogous to those obtained in man."^ 



Attempts at passive immunization have been entirely without 

 success. 



The occurrence of a Wassermann reaction was formerly supposed to 

 indicate the existence of specific syphilitic antibodies in the serum of 

 patients. Our more recent information regarding this reaction seems to 

 show that it depends upon the presence in the serum of syphilitic 

 patients of substances produced indirectly because of the presence of 

 sjrphilitic infection. It may be a relative increase of globuUns or, as 

 Schmidt has suggested, a change in the physical state of the globulins 

 or other substances present in the serum. At any rate it has been found 

 that the fixation of complement in the Wassermann reaction does not 

 depend upon the occurrence of a specific antigen-antibody reaction. 

 In the first place the antigens most commonly used, and successfully 

 so, in the Wassermann reactions, are non-specific lipoidal extracts of 

 normal organs. This alone would show that the specific spirochsetal 

 substance has no relation to the reaction. Again it has been demon- 

 strated that extracts of cultures of the Spirochseta pallida as well as ex- 

 tractions from the testes of syphilitic rabbits do not furnish an antigen 

 suitable for the Wassermann reaction. This has followed especially 

 from the work of Noguchi,^ of Craig and Nichols,^ and of others. This 

 forms a corollary to the other experiments previously mentioned and 

 shows that, whatever the Wassermann reaction may be (and space does 

 not permit us to review the theories, especially since none are definitely 

 proven), it is not a specific complement fixation in the sense of Bordet 

 and Gengou. It must be admitted, therefore, that our knowledge of 

 syphilis immunity is in its infancy and that we know very little about 

 the systemic reactions which follow infection with the Spirochseta 

 pallida. 



The fact that the syphihtic virus does not pass through a filter has 

 been demonstrated by Klingmiiller and Baermann,* who inoculated 

 themselves with filtrates from syphilitic material. 



' Fori Prowozefc, "Handbuch der pathogenen Protozoen," i, 1912, Leipzig, Bartsch. 



'' Noguchi, Jour. Am. Med. Assoc, 1912. 



' Craig and Nichols, Jour. Exp. Med., xvi, 1912. 



* Klingmuller und Baermann, Deut. med. Woch., 1904. 



