144 



HAEMOLYSIS EHRLICH'S RESEARCHES 



following way that such actually occurred : He worked with the 

 serum of a goat which had been injected with and was haemolytic for 

 the red blood-corpuscles of a sheep. He heated this immune serum 

 to 56 C. to destroy complement, and added some sheep's cor- 

 puscles ; the mixture was then centrifugalized, the supernatant fluid 

 then pipetted off, and replaced by normal saline solution. The red 

 corpuscles were to all appearance unaltered, but it was now found 



FIG. 27. HEATED IMMUNE SERUM ADDED TO RED BLOOD - CORPUSCLES, 

 WHICH ARE APPARENTLY UNALTERED, BUT ARE IN REALITY "SENSITIZED." 



FIG. 28. EFFECT OF ADDITION OF FRESH NORMAL SERUM TO SENSITIZED 



CORPUSCLES. 



Complement is now linked up to the corpuscles, and haemolysis takes place 

 when they are incubated at 37 C. 



that if a small amount of normal goat serum were added and the 

 mixture incubated, haemolysis occurred. It was evident, therefore, 

 that the corpuscles underwent some change in virtue of their stay 

 in the heated immune serum, though no alteration was obvious. 



In a further experiment he showed that the change consisted in 

 the abstraction of the amboceptor from the fluid. This appeared 

 from the fact that if the supernatant fluid from the last experi- 

 ment were pipetted off, fresh normal goat's serum added (to supply 

 complement), and the mixture tested with sheep's corpuscles, no 



