274 PROTEIN POISONS 



had but little or no effect on the temperature of the animal, 

 while small doses frequently repeated caused rapid eleva- 

 tion of temperature, and death within ten to twelve hours. 

 Here, again, small doses kill while larger ones are without 

 visible effect. The explanation is in our opinion the same 

 as that given for the bacterial suspensions. When 1 c.c. 

 of the egg-white dilution is injected into the ear vein of 

 the rabbit and diluted with all the blood in the animal 

 body, the molecular surface of the foreign protein is im- 

 mensely greater than when 10 c.c. of the egg-dilution is 

 injected. The egg-white has no poisonous action until it 

 is split up by ferments, and the rapidity and completeness 

 with which this is done is determined in part at least by 

 the extent of the molecular surface of the substrate. The 

 same thing is seen in the action of the precipitins. An 

 excess of the antigen prevents precipitation. We believe 

 the matter of molecular surface exposure to be of great 

 importance in the various phenomena of anaphylaxis. The 

 greater it is in the anaphylactogen the more potent is its 

 action both in sensitizing and on reinjection. 



Friedberger suggests that in the preparation of the 

 anaphylactic poison in vitro, excess of the anaphylactic 

 serum or prolonged time exposure may carry digestion 

 beyond the formation of the poison; itself being split up. 

 This is in accord with our findings as reported below. 



The formation of the anaphylactic poison from soluble 

 proteins in vitro was first done in our laboratory. 1 The 

 importance of this matter leads us to reproduce the experi- 

 mental part of our report: 



Our method of procedure is as follows: Experimentation 

 has so far been confined to guinea-pigs. The chest of the 

 etherized animal is opened and the blood is drawn from 

 the heart into sterilized tubes and thus the serum is obtained. 

 The animal dies from bleeding. The organs are rubbed 

 up in a conical glass with sand, stirred with 30 c.c. of physio- 

 logical salt solution, and allowed to stand for subsidence 



1 Zeitsch. f. Immunitatsforschung, xi, 673. 



