586 ANAPHYLAXIS 



kills the animals, death being preceded by all the symptoms of acute 

 anaphylactic intoxication. This toxic moiety has been obtained by 

 this method from the most diverse proteins, and seems to be the same for 

 all, the specificity residing in the non-toxic attached group. This and 

 other observations led Vaughan and his collaborators to formulate the 

 hypothesis that the non-toxic and specific intramolecular group of a 

 protein serves to stimulate the body-cells to produce specific proteolytic 

 enzymes, and that upon the injection of a second dose of the same 

 protein, these enzymes at once disintegrate it, setting free the toxic 

 group that produces the lesions and symptoms of acute anaphylactic 

 intoxication. This protein cleavage in vivo is entirely analogous to 

 the cleavage process occurring in vitro with the alcoholic sodium hydroxid 

 solution, and the poison in both instances is regarded as the same. 



2. Mention has previously been made of the protein poison obtained 

 by' Friedmann by digesting ox corpuscles with immune and normal 

 rabbit serum, and by Weichardt as the result of the digestion of placental 

 protein with immune rabbit serum. In 1910 Friedberger, 1 by digesting 

 a serum precipitate with normal guinea-pig serum, obtained a similar 

 toxic substance; by means of ferments he secured a protein cleavage 

 poison that, when injected into normal guinea-pigs, produced the 

 symptoms of acute anaphylaxis, the process being entirely analogous to 

 that obtained by Vaughan and Wheeler by protein splitting with alcoholic 

 sodium hydroxid solution. Subsequent studies by Friedberger and his 

 collaborators 2 showed that similar protein poisons could be obtained by 

 digesting microorganisms, as, e. g., Bacillus prodigiosus, Bacillus typho- 

 sus, and Bacillus tuberculosis, with normal guinea-pig serum. Fried- 

 berger and Nathan 3 obtained the poison by digesting normal horse serum 

 with fresh guinea-pig serum; Bordet, 4 by digesting agar with fresh 

 serum; Dold and Aoki, 5 by digesting meningococci, streptococci, 

 pneumococci, gonococci, and various other microorganisms with fresh 

 normal gunea-pig serum. As was expected, cleavage could be facili- 

 tated and hastened by using immune serum specific for any particular 

 bacterial or other protein. 



These results indicate that fresh normal guinea-pig serum contains a 

 normal thermolabile non-specific proteolytic ferment capable of split- 

 ting some, through probably not all, proteins, a view advanced by 



1 Zeitschr. f. Immunitatsf., 1910, 4, 636. 



2 Zeitschr. f. Immunitatsf,, 1911, 9, 369. 

 . 3 Zeitschr. f. Immunitatsf., 1911, 9, 567. 



4 Compt. rend de Soc. de Biol., 1913, Ixxiv, No. 5. 

 6 Zeitschr. f. Immunitatsf., 1912, 12, 200. 



