344 



STUDIES IN IMMUNITY 



TABLE VIII 



Controls: 

 G. p. corpus- 

 cles, 5% sus- 

 pension in 



0.85% NaCl. Hemolysis. 



1 c c S. dog 50-51 .0.5 c.c. Alex, guinea-pig 0.5 c.c. complete 10 mins. 

 1 c.c. S dog 56. 0.5 c.c. Alex, guinea-pig 0.5 c.c. complete 10 mins. 



In these experiments we again see the disadvantage of employing 

 a 5 per cent suspension owing to the inhibiting action of the great 

 excess of salt solution on a weak alexin (series I and II, III and 

 IV, etc.). Heating dog serum to 51 degrees merely weakens the 

 toxic and combining activity of the dog alexin; 56 C does not 

 wholly destroy either the toxic or the combining activities of the 

 alexin, but destroys one as much as the other. The normal immune 

 body apparently suffers no impairment by heating to 56 degrees 

 (Controls). 



CONCLUSIONS. 



1. Suspensions of blood corpuscles for hemolytic experiments 

 of 5 per cent are disadvantageous unless the excess of normal saline 

 solution be removed, as alexic power is often entirely inhibited by 

 the great excess of fluid. 



2. Heating to 55 degrees for one-half hour does not affect the 

 power of ox or rabbit corpuscles, even when hemolysis is produced, 

 to absorb suitable immune bodies or alexins. 



3. A given immune serum, active against rabbit corpuscles, 

 contains a simple immune body as regards affinity for various 

 alexins. 



4. So-called " complementoids " (to judge from the test example) 

 are simply " complements " (alexins) in which both the combining 

 power and the hemolytic power are weakened. 



