116 Chapter V 



Ehrlich and Morgenroth have satisfied themselves that their anti- 

 haemotoxin exerts no influence, either upon the red corpuscles or 

 upon the fixative, and is only capable of preventing the action of the 

 cytase. They introduced red corpuscles of the rabbit into a mixture 

 of goat's serum, heated to 56 C. and thus only retaining its fixative, 

 and anticytase serum. The fluid bathing the red corpuscles was then 

 removed by centrifugalisation and the corpuscles were mixed with 

 normal haemolytic horse's serum. Solution of the red corpuscles 

 took place at once as the anticytase had been completely removed 

 during centrifugalisation, being combined with neither the red 

 corpuscles nor the fixative. 



These investigators have obtained various anticytases by injecting 

 serum of various species of animals into other mammals. They ob- 

 served, however, that injections of the serum of an allied species did 

 not bring about the formation of anticytases. Thus the injection of 

 goat's serum into sheep, or of that of sheep into goats, never produced 

 anticytase serum. 



In addition to antihaemotoxic serums several other analogous 

 [124] anticytotoxic serums have now been obtained. Thus Delezenne has 

 prepared serums which prevent the action of neurotoxin and of the 

 cell poison which destroys the liver cells. We 1 have been able to 

 obtain a rabbit's serum which prevents the spermatozoa of this rodent 

 being rendered motionless by the specific spermotoxin of the guinea- 

 pig. More recently Metalnikoff 2 , working in my laboratory, has 

 prepared another antispermotoxic serum which prevents the specific 

 spermotoxiu of the rabbit from arresting the movement of the 

 guinea-pig's spermatozoa. 



As the history of these antispermotoxins presents certain interest- 

 ing general features we may with advantage, perhaps, dwell on some 

 of their characters. The two antispermotoxins mentioned above are 

 distinguished by certain peculiarities. When Metalnikoff set to work 

 to inject rabbit's spermotoxin into guinea-pigs, he thought that he had 

 an easy task before him and that after a few injections the guinea- 

 pig's serum would become antispermotoxic. This, however, was not 

 the case. The serum from these animals when mixed, with spermotoxic 

 serum was powerless to prevent the immobilisation of the spermatozoa 

 of the guinea-pig. It was only when he heated the serum of his treated 

 guinea-pigs to 56 C. that the antispermotoxic power appeared with 



1 Ann: de Vlnst. Pasteur, Paris, 1900, t. xiv, p. 5. 



2 Ibid., p. 583. 



