64 POISONOUS PROTEINS 



as antitrypsin. So far as I know, Camus and 

 Gley were the first to show experimentally that 

 blood serum inhibits peptic and tryptic action. 

 These investigators observed that fibrin or co- 

 agulated egg-white placed in serum and treated 

 with active pepsin or trypsin remains intact. 

 More extended observations have shown that 

 many, if not all, kinds of proteolytic digestion, 

 are retarded, often wholly arrested, by the pres- 

 ence of blood serum. There is another inter- 

 esting fact in this connection. The injection of 

 proteolytic ferments into an animal, especially 

 repeated injections, increases the potency of the 

 blood serum in the inhibition of the action of 

 that ferment. Antibodies are formed and ac- 

 cumulate in the blood after repeated injections 

 of pepsin, trypsin, rennin, etc. The effect of 

 such injections is similar, probably closely re- 

 lated, to that which follows injections of toxins. 

 But little is known concerning these antibodies 

 in case of either the ferments or the toxin. 



Delezenne and Pozerski first showed that 

 chloroform removes from blood serum the anti- 

 proteolytic body. They found that blood serum 

 has no digestive action on gelatin under ordi- 

 nary conditions, but that blood serum which has 

 been extracted with chloroform promptly di- 

 gests gelatin. The researches of Jobling and 



