48 INFECTION AND RESISTANCE 



stance to which he ascribes the toxin-binding properties. Overton 

 and Bang 65 found, furthermore, that cholesterin and lecithin inhibit 

 the action of cobra venom, a poison which is in so many ways similar 

 to those produced by bacteria. Taking into consideration all avail- 

 able evidence, we are forced to admit that the lipoids seem to play an 

 important role in determining the selective action of the nervous sys- 

 tem by the bacterial poisons. It may not, of course, be an influence 

 depending merely upon the solubility of the harmful substances in 

 the lipoids themselves. For, as Bang expresses it, "the lipoids pos- 

 sess to a high degree the property of altering by their presence the 

 solubilities of other bodies/' and it is quite possible that in the tis- 

 sues they are present as lipoid-protein combinations. Their action 

 in determining the solubility of toxins in a given cell may therefore 

 be a purely indirect one. 



It is of some interest in this connection to recall the experiments 

 of De Waele, 66 which bring out another clear analogy between alka- 

 loids and bacterial poisons in their relation to lecithin. He found 

 that the addition of small quantities of lecithin increases the activity 

 of both toxins and alkaloids in the animal body, whereas larger 

 amounts inhibit both. 



65 See Ivar Bang, "Biochemie der Lipoide," Bergmann, Wiesbaden, 1911. 



66 De Waele. Zeitschr. f. Immunit., Vol. 3, 1909, p. 504. 



