304 INFECTION AND IMMUNITY 



Lieb and Dwyer * has been able to show that action of the salt pre- 

 vents spasm of the smooth muscles and need not necessarily be inter- 

 preted as indicating an inhibition of complement action. 



An important development of Friedberger's work has been the dem- 

 onstration that when sensitized antigen, either in the form of precipitate 

 or of bacteria, is subjected in vitro to the action of alexin or complement, 

 toxic substances (anaphylatoxins) are formed, which injected into 

 guinea-pigs produce symptoms entirely analogous to anaphylactic 

 shock. This has led to a recognition of the great importance of 

 Vaughan's earlier work in pointing to the possibility of anaphylactic 

 shock being the result of poisons formed by the split products of pro- 

 teins. Whether or not these anaphylatoxins are actually produced in 

 the circulation of animals in the process of anaphylactic shock cannot 

 be definitely asserted at present. It seems rather unlikely that they 

 are produced in the circulation to any extent during shock produced 

 by the dissolved proteins such as foreign serum or egg albumin. It is 

 not' impossible that they may be formed in the course of cell anaphylaxis 

 and that they may play a considerable part in the toxemia accompanying 

 infectious disease. In fact, their universal production from practically 

 all known bacteria, and the experiments of Vaughan 2 which have shown 

 that similar poisons produced from proteins can lead to typical tempera- 

 ture reactions in animals if carefully and systematically injected, has 

 cast a certain amount of doubt upon the existence of true endotoxins 

 and has suggested to many workers the possibility that the toxemia 

 produced with such bacteria as typhoid bacillus and others may be 

 largely a protein split product intoxication or a sort of prolonged ana- 

 phylactic poisoning. 



It seems unquestionable that this altered state of reaction capacity 

 to specific antigens which v. Pirquet has called allergic, and which we 

 speak of broadly as anaphylaxis, underlies many conditions observed 

 in the human being. Most important among these is the frequently 

 observed serum disease which occurs after the injection of horse serum 

 and other sera in the form of antitoxins in the human being. It may 

 also confirm the pathological basis of such conditions as asthma and 

 hay fever, food idiosyncrasies, and in a localized way it is probably 

 the basis of such skin reactions as the tuberculin, luetin, and mallein 

 reaction. 



1 Zinsser, Lieb, and Dwyer, Proc. Soc. Exper. Biol. and Med., Vol. XII, No. 8. 

 May 19, 1915. 



2 Vaiighan, Protein Split Products, etc., Lea and Febiger, 1913. 



