SCIENTIFIC PROCEEDINGS. 



Abstracts of the Communications. 

 Thirtieth meeting. 



College of Physicians and Surgeons, Columbia University. 

 October 21, igo8. President Lee in the chair. 



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Studies on the chemistry of anaphylaxis. 



By H. GIDEON WELLS. 



\Frojn the Pathological Laboratory of tlie University of Chicago.'^ 

 Egg albumin, freed from the other proteins of egg white by 

 repeated crystallization, produces typically the anaphylaxis re- 

 action. It sensitizes in doses as small as one twenty-millionth of 

 a gram, fatally in doses of one millionth of a gram. The mini- 

 mum lethal dose for sensitized pigs is about one half a milligram 

 by intraperitoneal injection, and about one tenth to one twentieth 

 of a milligram when injected into the circulation. The unpurified 

 proteins of egg white are much less active, the minimum sensitiz- 

 ing dose being about one hundred times greater and the minimum 

 lethal dose being five times greater than with purified egg albumin. 

 This suggests that inhibiting substances are possibly present in 

 crude egg white. 



The minuteness of the minimum sensitizing and intoxicating 

 do.se of pure protein seems to indicate conclusively that both the 

 sensitizing and the intoxicating agent are one and the same kind 

 of protein molecule, or else two different constituents of the same 

 molecule. 



Gelatin seems to be devoid of the power of participating in the 

 anaphylaxis reaction, either with itself or with other proteins. 

 This may be due to its poverty in aromatic radicals ; it probably 

 is not due to the heating that is necessary for the conversion of 

 collagen into gelatin. Addition of tyrosin to gelatin (without 



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