HEMOLYSINS 553 



propertv that had been demonstrated in the blood serum of 

 guinea pigs treated with rabbit's blood was shown to hold for 

 The sera of other species of animals treated with the blood 

 cells of a different species. Wassermann has formulated this 

 action as follows: "The serum of animals species A, after 

 these have been injected either subcutaneously, intraperito- 

 neally, or intravenously with erythrocytes of species B, 

 acquires an increased solvent action for erythrocytes of species 

 B, and onlv for this species. (There are a few exceptions to 

 this general rule). We call this hemolysis, and the substances 

 which affect the solution of the red cells, hemolysins or hemo- 

 toxins." 



Bordet has been able to show that the solvent power of the 

 specific hemolvsins depended on the combined action of two 

 constituents of the specific serum. Thus, when ^ the fresh 

 hemolvtic serum was heated for a half hour at 55° C. it lost 

 its power. If to this inactive serum a very small amount of 

 the serum of a normal guinea pig was added, the full hemo- 

 lytic power was restored to this inactive serum. In other 

 words, it had been reactivated by this addition. This experi- 

 ment showed that the hemolytic action of the specific hemolytic 

 .serum depends upon two substances (i) the one destroyed by 

 heating to 55° C. and which is contained in the serum of the 

 normal untreated animal as well as in the specific hemolytic 

 serum, and (2) a substance that is able to withstand heating 

 to 55° C. and which is contained in the specific serum only. 



The substance which is destroyed at 55° C. and which 

 exists in the blood of the untreated animal and in the specific 

 serum constitutes the substances designed by Buchner as 

 alexins. It is the .substance which is not destroyed by heatmg 

 to 55° C. .and which is brought about by the action of the 

 blood of one species upon another and is known as the immune 

 body, or as termed by Buchner substance seJisibilatrice. 



§448. Agglutinating power of hemolytic serum. It 

 has been found in the experiments by Bordet that another 

 propertv was increased in the hemolytic serum, namely, the 



