130 



THE LYSINS. 



Fia. 1. 



Demonstrating Ehrlioh's Theory. ^,eomp]einent ; f, intermediary Body ; O, receptor; D, 

 part of cell ; E^ toxophorouB group of toxin ; J^, haptophorous group. 



If there be no receptors the intermediary body cannot combine 

 with the corpuscle and consequently there is no hemolysis. Anti- 

 hemolysins are supposed to be formed in the body of the animal 

 treated with hemolytic serum in the same way that antitoxins are 

 formed in the bodies of animals immunized to the toxins. If a 

 hemolytic serum be injected into an animal in small but gradually 

 increased doses at intervals, immunity to such serum is obtained and 

 the serum of the animal thus immunized contains an anti-hemolysin. 

 When a small amount of the hemolytic serum is injected it is taken 

 up by the receptor in the blood cell, and provided that the amount 

 of the hemolytic serum injected is small, the blood corpuscle is not 

 destroyed ; and needing for the performance of its function the re- 

 ceptor which has combined with the hemolysin, it throws out other 

 receptors ; and as in the case of the production of antitoxin, a point 

 is reached when there is over-production of receptors and those not 

 needed by the cell and not taken up by the hemolysin are cast off in 

 the blood and constitute the anti-hemolysin. Ehrlich and Morgen- 

 roth prepared an anti-isolysin in the following manner : A small 

 goat (No. 10) whose blood corpuscles had been shown to be highly 

 susceptible to the serum of goat A was treated at intervals with this 

 serum and an anti-body obtained. When 0.4 c.c. of the serum of goat 

 No. 10 was added to one c.c. of a five per cent, dilution of the blood 

 of a goat which had been found susceptible to the serum of goat A, 

 no hemolysis occurred. However, when the blood corpuscles of goat 



