n. CONCERNING ILEMOLYSINS. 1 

 SECOXD COMMUNICATION. 



By Professor Dr. P. EHRLICH and Dr. J. MORGENROTH. 



IN a previous paper 2 we demonstrated the relations existing 

 between the red blood-cells to be dissolved and the two components of 

 a specific haemolysin produced by immunization. It will be remem- 

 bered that we termed the two components of the specific serum 

 immune body and addiment. We were able to show that the immune 

 body combines with the erythrocytes of the species whose blood 

 was injected, since it has a specific affinity for these cells. We showed 

 further that the addiment, the unstable (labile) ferment-like body 

 which effects the solution of the blood-cells, is tied to these cells 

 indirectly by means of the immune body. 



Proof was thus afforded that, in conformity with the require- 

 ments of the side-chain theory, the immune body possesses one 

 haptophore group by means of which it combines with the erythrocytes 

 of the corresponding blood, and a second haptophore group with less 

 affinity by which it combines with the addiment and transfers the 

 action of the latter to the blood-cells. 



At that time we availed ourselves of the serum of a goat which 

 had been treated for some time with subcutaneous injections of a 

 sheep serum rich in blood corpuscles. Corresponding to this treat- 

 ment, the serum of the goat possessed a moderate degree of solvent 

 action on sheep blood-cells. 



In order to continue these studies it seemed essential to make 

 use of a serum derived from an animal treated for some time with 

 full blood, a serum that would accordingly possess a higher degree 

 of activity. For this purpose we began the immunization (Nov. 12 



1 Reprinted from Berl. klin. Wochenschr. 1899, No. 22. 



2 See pages 1-10 of this volume. 



11 



