300 INFECTION AND IMMUNITY 



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

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

 thus shown that the specificity of the hemolysins extends even within 

 the limits of species, and is, to a certain extent, an individual property. 



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

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

 has, so far, been unsuccessful. 



Ehrlich and Morgenroth, in the course of these experiments, 

 furthermore 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 Morgen- 

 roth that the failure of autolysin production may be due to a lack 

 of suitable receptors in the animal for its own cells. 



The clinical significance of the presence of isolysins and possibly 

 of autolysins in human beings is too evident to require much dis- 

 cussion. A practical and extremely interesting result which these 

 investigations have yielded is that of Donath and Landsteiner, 57 

 who discovered an autolysin in the blood serum of patients suffering 

 from paroxysmal hemoglobinuria. In these cases the sensitizing 

 substance or amboceptor appeared to be absorbed by the red blood 

 cells only at low temperatures 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 paroxysmal hemoglobinuria. 



Isoagglutinins and blood typing in human beings are discussed 

 in a subsequent section. 



57 Donath und Landsteiner, Munch, med. Woeh., xxxvi, 1904. 



