78 ANTIBODIES, IMMUNITY, WASSERMANN SERUM TEST 



hemolysins has been called amboceptor, which means, literally trans- 

 lated, "double catcher," or "double taker." 



Deviation of Complement. To a solution containing a hemolytic 

 amboceptor and a complement, something may be added which will 

 unite with the complement, and the solution will then loose its 

 property of dissolving blood corpuscles (to produce hemolysis). The 

 complement has united to something else, and can no longer unite 

 with the amboceptor, a complete hemolytic system cannot be formed, 

 and, therefore, hemolysis cannot take place. In other words, comple- 

 ment deviation prevents hemolysis. 



Complement deviation can be brought about by several means; 

 for instance, by the use of anticomplements or by the presence of 

 an antigen uniting with its antibody. These two, when united, 

 generally form a combination which will anchor to itself the com- 

 plement and so prevent hemolysis. Complement deviation has been 

 here explained somewhat at length, because it has become a most 

 important method in practical serum diagnosis. The principle was 

 discovered by Bordet and Gengou. They found that if an antigen 

 be permitted to unite with its specific immune body or immune 

 amboceptor, something is formed by the union which will attract to 

 itself the complement of a hemolysin, so that the latter can no longer 

 bring about a solution of the red blood corpuscles. This peculiar 

 occurrence or phenomenon may be used to detect antibodies. Sup- 

 pose the presence of certain antibodies is suspected in the blood 

 serum of a person or animal they can be detected in the following 

 manner: Add to the blood serum the antigen of the suspected 

 antibodies and a hemolytic complement. Later, add the hemolytic 

 amboceptor and some red blood corpuscles. If solution of the latter 

 occurs the complement is not deviated, because the suspected anti- 

 body is not present, and could not unite with the antigen, and could 

 not, therefore, produce complement deviation. If, however, there is 

 no hemolysis of the red blood corpuscles it clearly shows that the 

 suspected antibody is present. It has united with its antigen and 

 they in their union have attracted the complement, which is no longer 

 present in the free state; hence, the hemolytic chain, composed of 

 red blood corpuscles, hemolytic amboceptor, and hemolytic comple- 

 ment, cannot be formed and hemolysis cannot occur. 



The Wassermann Test. Syphilis in man is often very difficult to 

 diagnosticate, and it is still more difficult to determine whether the 

 disease has been cured or whether it is still going on in a latent form. 

 The phenomenon of complement deviation under properly arranged 

 tests has, however, furnished a means of an almost absolutely infal- 

 lible diagnosis. Since the same principle may be applied to diseases 

 of domestic animals, and, perhaps, particularly to dourine or horse 

 syphilis, also very difficult to diagnosticate, it is important to know in 

 detail the steps of the serum diagnosis of syphilis, which has assumed 

 such great importance in human medical practice. The author has 



