94 



COLLECTED STUDIES IN IMMUNITY. 



this case, so that later investigators (Buchner, Rehns, Bulloch) 

 have also employed this useful combination. In many cases, most 

 easily by means of intraperitoneal injections of the ox blood, a potent 

 hsemolysin is produced of which 0.005-0.0005 cc. suffices to dissolve 

 1 cc. of the 5% ox-blood mixture. Since the production of the 

 immune body is unaccompanied by any increase in complement (as 

 von Dungern showed in just this case) it is always necessary, in 

 order to bring the total amount of immune body into action, to 

 add extra complement. This is found in large amounts in the serum 

 of rabbits and especially in that of guinea-pigs. 



Now we have observed that the serum of these rabbits which had 

 been immunized with ox blood is able to dissolve not only the blood- 

 cells of oxen, but also those of goats. The following table shows a 

 comparison of the solvent action of several of these sera on the blood- 

 cells of oxen and of goats. Guinea-pig serum (0.1 or 0.15 cc.) was 

 used as complement since rabbit serum itself, in the doses required, 

 often exerted a haBmolytic action on the goat blood-cells. 



TABLE I. 



ACTION OF THE IMMUNE BODY OF THE RABBIT IMMUNIZED WITH Ox BLOOD, ON 

 Ox BLOOD, AND ON GOAT BLOOD. 



This table shows that the hsemolytic action of the immune body 

 is always less on goat blood than on ox blood, and that the ratio 

 of the solvent doses for the two species of blood is not constant but 

 varies within fairly wide limits, as can be seen from the last column. 



