286 INFECTION AND IMMUNITY. 



due to the fact that in the aqueous extracts, a 

 large amount of protein is present with the lipoids 

 on which the antigenic action depends, and that 

 these lipoids become bound to the protein through 

 heating; further, they believe that these lipoid 

 substances may be extracted with water in syph- 

 ilitic liver because through degenerative processes 

 they become split off, while in normal organs they 

 must be split off by alcohol and heat. 



They conclude that the antigen is therefore of 

 non-specific lipoid nature and that it acts as 

 activating the complement binding property of 

 syphilitic serum. 



The nature of the substance in the serum of 

 syphilitics which in combination with antigen 

 inhibits complement action, is still unknown. 

 Noguchi has shown that it begins to show the 

 effects of heat at 45 C. At 56 C. it is somewhat 

 diminished in activity and at 62 C., its activity 

 is lost. It has been thought of as an antibody 

 because of its development with the development 

 of the disease and its disappearance with the cure 

 by specific treatment. 



As was stated in the beginning of the chapter, 

 the various materials used in complement devia- 

 tion may of themselves have anticomplementary 

 properties. In addition, it might be stated that 

 extracts of organs may also have a hemolytic 

 action. The importance of quantitative relations 

 and central experiments will therefore be appar- 

 ent. The Noguchi modification of Wassermann's 

 method has given satisfactory results in a large 

 number of cases. The preparation of materials 



