Studies on So-called Protective Ferments. 19 



14 (1078) 



Studies on so-called protective ferments VIII. On the mechanism 

 of anaphylaxis and antianaphylaxis. 



By J. Bronfenbrenner. 



[From the Research Laboratories of the Western Pennsylvania 

 Hospital, Pittsburgh, Pa.] 



As we have reported a little over a year ago, 1 the interaction be- 

 tween an immune serum and its corresponding substratum is fol- 

 lowed by a formation of toxic split products. We found that the 

 toxic material originated not from the substratum or antigen, but 

 from the serum itself. 2 These findings threw light on some of the 

 unsettled questions in the theory of anaphylaxis and antianaphy- 

 laxis. Experiments conducted with the view of correlating our 

 findings with the accepted views on this subject, suggested a 

 following hypothesis about the nature and mechanism of ana- 

 phylaxis. 



Blood serum contains normal proteolytic ferments which 

 require special conditions of the medium in order to exhibit their 

 activity. Normally the degree of concentration of colloids 

 in the serum offers an obstacle to the activity of these ferments. 

 In the experiments in vitro it is possible to change the degree of 

 concentration of colloids in the serum, thus diminishing its anti- 

 tryptic inhibiting power and setting free the ferments. 8 



This activation of normal serum can be accomplished by 

 mechanical adsorption, as in experiments of Plant, Peiper and 

 others, or by the dissolution of some of the serum colloids, as in 

 the experiments of Jobling. 4 In either case the degree of disper- 

 sion of remaining colloidal particles is increased and thus ferments 

 are allowed to act. 



1 Bronfenbrenner, Pennsylvania Slate Journal, 1914, October, p. 20. 



1 Bronfenbrenner, Proc. Soc. Exp. Biol, and Med., 1914, XII, p. 7-8; also 

 Journ. Exp. Med., 1915, Vol. XXI, No. 5, p. 480. 



* Bronfenbrenner, Journ. Exp. Med., 1915, XXI, No. 3, p. 221. 



4 Jobling and Peterson, Journ. Exp. Med., 1914, Vol. XIX, p. 239. Though the 

 authors find it necessary to remove the lipoid in order to activate the enzyme, our 

 own experiments show that the removal of lipoid is not necessary. Mere bubbling 

 of ether vapor through the serum accomplishes the activation. 



