CYTOLYSIXS, BACTERIOLYSINS, AXD HEMOLYSINS 159 



amboceptor is made up of two haptophore groups, one uniting 

 with the specific cell, and called the cytophilous haptophore, the 

 other uniting with the complement, and called the complement- 

 ophilous haptophore. The injection of a serum containing ambo- 

 ceptors into a different species of animal has been claimed to cause 

 the production of anti-amboceptors. That these anti-amboceptors 

 are formed was held because, by adding the serum produced by 

 immunization with amboceptors to a solution of the amboceptors, 

 the solution will be found to have lost all cytolytic power when the 

 complement is added. The fact that the amboceptor has the two 

 haptophore groups would make it seem probable that two kinds of 

 anti-amboceptors may be formed, one of which unites with the 

 complementophilous, the other with the cytophUous, haptophore. 

 That such are actually present may be demonstrated by carefully 

 planned experiments. Add the anti-amboceptor solution to the 

 solution of amboceptor, then add the specific cell antigen, wash the 

 cells repeatedly with physiological salt solution by means of centri- 

 fugation, and add the complement. No cytolysis will take place, 

 but, on the addition of fresh amboceptor, cytolysis will occur. 

 It is evident that, in the first instance, the amboceptor has been 

 prevented from uniting with the cell by the cytophilous anti- 

 amboceptor. The anti-amboceptor for the complementophilous 

 haptophore may be demonstrated by adding amboceptor to the 

 antigenic cell; to a portion add anti-amboceptor. To each por- 

 tion then add complement, and it will be found that no cytolysis 

 occurs when anti-amboceptor has been used, while it does occur in 

 the other tube. The anti-amboceptor in this case has prevented 

 the complement from attaching itself to the amboceptor, and 

 consequently prevented cytolysis. Some doubt has been thrown 

 upon the sufficiency of the above explanation, for it has been shown 

 that the anti-amboceptor for goat anticholera serum will inhibit 

 likewise the action of the goat typhoid serum. 



Structure of the Complement. The complement is believed to 

 consist of two groups a haptophore, which unites with the ambo- 

 ceptor, and an active or lytic group, the zymophore. Careful 

 heating of complement is found to destroy the zymophore without 

 injuring the haptophore. Such a changed complement is called a 

 complementoid. It has been claimed that immunization of one 



