NATURE OF HEMOLYSINS 385 



power of "lysing" or breaking up red blood-corpuscles, or so altering their 

 envelop as to allow the hemoglobin to escape. 



Nomenclature. Normal hemolysins are those found in normal se- 

 rums; specific or immune hemolysins are those produced as the result of 

 the injection of blood-corpuscles from an animal of a different species. 

 Heterolysins are the hemolysins formed by immunization with corpuscles 

 of a different species (the immune hemolysins). Isolysins are hemoly- 

 sins for the corpuscles of animals of the same species. Autolysins are 

 hemolysins that act upon the corpuscles of the same animal and are quite 

 rare. It should be remarked that isolysin and autolysin are not strictly 

 synonymous terms, as the former does not act upon the corpuscles of the 

 animal producing the hemolysin, but may hemolyze the corpuscles of 

 other animals of the same species. For example, Ehrlich has shown that 

 the serum of a goat that had received several injections of blood from 

 other goats, although actively hemolytic for the corpuscles of goats 1, 2, 

 4, 5, 6, 9, and less so for goats 3 and 8, was not able to hemolyze those of 

 goat 7 or of itself at all. This immunity of the corpuscles of an animal 

 to its own isolysin was subsequently shown to be due to a complete 

 absence of suitable receptors in its corpuscles. Therefore in cases in 

 which a large internal hemorrhage occurs and the blood is absorbed an 

 autohemolysin is not produced, or produced only in small amounts, and 

 likely to be followed by the formation of an anti-autolysin which 

 regulates the process of blood destruction within physiologic limits. 

 Although little is known concerning the processes of normal blood destruc- 

 tion, as in the disposal of old erythrocytes, it is possible that an auto- 

 hemolysin is being produced, and that its activity is held within normal 

 limits by an anti-autolysin. A disturbance of this physiologic equilib- 

 rium may then be the basis of certain types of primary anemia character- 

 ized by excessive blood destruction. 



Nature of Hemolysins. According to the side-chain theory, he- 

 molysins are amboceptors or antibodies of the third order, requiring the 

 action of a complement before hemolysis can be produced (Fig. 105). 

 Bordet showed that two substances were concerned in the phenomenon 

 of serum hemolysis, although his views on the mechanism of the process 

 differ from those advanced by Ehrlich and Morgenroth. 



Ehrlich argued that the hemolytic amboceptor or hemolysin must 

 be an antibody to the receptors of the red blood-corpuscles used in the 

 process of immunization, and if this is true, it ought to unite with the 

 corpuscles. Taking the serum of a goat that had been injected with and 

 was hemolytic for the erythrocytes of a sheep, he destroyed the comple- 

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