June 3, 1918 



Destruction of Tetanus Antitoxin 



491 



any of the previous investigators mentioned on page 473; it probably 

 was not looked for. 



The figures in Table II for mixture B, experiment 5, are shown graphi- 

 cally in figure i . From such data, if none other were available, the 

 conclusion would be justified that the antibodies were separate from the 

 proteins, so far as one may be almost totally destroyed without any 

 detectable difference in the other. 



Mixture c — This mixture contained serum and trypsin. The origi- 

 nal object was to make certain that the trypsin was immunologically 

 neutral under the experimental conditions. The mixture was faintly 

 amphoteric to litmus-paper strips. In the experiment 3 mixture it was 

 faintly acid. The digestion in mixture C was as rapid as in mixture D, 

 which contained 0.5 per cent of sodium carbonate and trypsin. In 18 

 days, in mixture C, 80 per cent of the coagulable protein was digested 

 past the coagulable 



1^ 



e /7 76 



Fig. 2. — The destruction of tetanus antitoxin ( X ) by tryps in 



in solution amphoteric to litmus strips; the digestion of coagulable 



protein past the coagulable stage ( O ); the liberation of free 



amino nitrogen ( 1 ). Mixture C, experiments 4-5.1. 



stage and 57 per cent 

 of the total amino 

 nitrogen was liberated. 

 During this same time, 

 82 per cent of the anti- 

 toxin units were de- 

 stroyed. The experi- 

 mental data are 

 graphically repre- 

 sented in figure 2. 

 Because the rate of 

 protein splitting is 

 practically the same as 

 the rate of antitoxin 

 destruction in such a 

 mixture, the supposition that the antitoxin and the protein are identical 

 substances would be a reasonable one were it not for the fact that the 

 data vath mixture B show that the antitoxin may be destroyed with- 

 out protein splitting. 



Mixture d. — The results were practically the same as with mixture C. 



Mixture E. — This contained trypsin and sodium carbonate in the 

 same quantities as mixture D, but no tetanus serum. Instead anthrax 

 serum was used; in other B mixtures normal horse serum was used. 

 This mixture obviously contained no tetanus antitoxic units, and was 

 used for the purpose of ascertaining with certainty that the tetanus 

 toxin was not destroyed by the largest amounts of trypsin and sodium 

 carbonate in doses of other mixtures. (See page 484.) The highest 

 final concentration of sodium carbonate in the toxin-antitoxin mixture 

 injected was 0.008 per cent. 



