TOXINS AND ANTITOXINS 269 



received wounds which may, if left untreated, give 

 rise to lockjaw. Tetanus antiserum has been used 

 on an unprecedented scale in the present war and 

 has saved the lives of innumerable soldiers. 



The study of the mode of action of antitoxin 

 upon toxin in the test-tube and in the animal body 

 has been fraught with difficulties because modern 

 chemistry is still incapable of explaining the com- 

 plex composition of the substances which act upon 

 each other. There have been various attempts to 

 explain the phenomena involved, and the explana- 

 tion which has perhaps afforded the best working 

 hypothesis and certainly most stimulated research 

 is that of Ehrlich. According to this author the 

 antitoxins are the products of the living cells of 

 the body which have reacted to the stimulus of a 

 corresponding toxin. A toxin is only capable of 

 producing disease in individuals whose body cells 

 contain substances capable of entering into chemi- 

 cal combination with the particular toxin. The 

 toxin upon entering the body is taken up by these 

 substances (called receptors) ; the cells react and 

 produce receptors in excess so that they are thrown 

 off into the blood stream, rendering the serum anti- 

 toxic. The receptors in the blood prevent the 

 toxin from reaching the susceptible cells. Or, as 

 Behring expresses it, the substance in the cell 

 which makes it susceptible to the effects of toxin 

 is the causative factor in recovery. 



Apart from the antitoxins the body is capable 



