248 INFECTION AND IMMUNITY 



causing hemolysis of the red blood cells of the particiilar goat whose 

 blood had been used for injection. It did not, however, possess the 

 power of producing hemolysis in the blood of all goats, nor did it pro- 

 duce hemolysis with the red corpuscles of its own blood. It is thus 

 shown that the specijB.city of the hemolysins extends even within the 

 limits of species, and is, to a certain extent at least, an individual 

 property. 



The production of autolysins, that is, of substances in the blood serupi 

 which will produce hemolysis of the individual's own corpuscles, has, 

 so far, been unsuccessful. 



Ehrlich and Morgenroth, in the course of these experiments, further- 

 more succeeded in showing that the injection of isolysins into animals 

 produced antiisolysins, and that these again were strictly specific. 



The almost universal failure of autolysin production has found no 

 satisfactory explanation. It is supposed by Ehrlich and Morgenroth 

 that autolysins may be formed, but are probably speedily neutralized 

 by the production of antiautolysins. 



The clinical significance of the presence of isolysins and possibly of 

 autolysins in human beings, is too evident to require much discussion. 

 A practical and extremely interesting result which these investigations 

 have yielded is that of Donath and Landsteiner,^ who discovered an 

 autolysin in the blood serum of patients suffering from paroxysmal 

 hemoglobinuria. In these cases the sensitizing substance or ambo- 

 ceptor appeared to be absorbed by the red blood cells only at low tem- 

 peratures—probably in the capillaries during exposure to the cold, and 

 hemolysis subsequently resulted in the blood stream by the action 

 of complement. These observations have been confirmed by other 

 writers, but the phenomenon is surely not present in all cases of paroxys- 

 mal hemoglobinuria. The writers have had occasion to examine care- 

 fully several clinically typical cases with negative results. 



» Donath vmd Landsteiner, Munch, med. Woch., xxxvi, 1904, 



