PROTEIN SENSITIZATION OR ANAPHYLAXIS 337 



Friedberger, Mita, and Kumagi 1 have prepared anaphyl- 

 atoxin by the action of the normal serum of the guinea-pig 

 on the crude toxins of tetanus and diphtheria, and the 

 venom of the cobra. They assume that the poison comes 

 from the cleavage of the toxins, an assumption which seems 

 to us wholly without warrant. Some years ago we precipi- 

 tated the crude toxins of tetanus and diphtheria with alcohol 

 and split up the precipitate with chemical agents by our 

 method, and obtained the protein poison, but we never 

 felt justified in even supposing that the poison came from 

 the toxins. Crude toxins and venoms are complex protein 

 substances, and because, the protein poison can be obtained 

 by the cleavage of these is far from proof that the poison 

 comes from the toxin constituent of such a mixture. Indeed, 

 one does not know that the active principle in these mixtures 

 is a protein. Until the toxins have been obtained in some- 

 thing like a pure state it is useless to speculate concerning 

 their split products. 



Bordet 2 has shown that anaphylatoxin can be obtained 

 by the action of the normal serum of the guinea-pig on agar, 

 and this has been confirmed by Nathan. 3 One-half gram of 

 agar is added to 100 c.c. of 0.85 per cent, salt solution and 

 sterilized by boiling. From 0.5 to 1 c.c. of this agar solution 

 is incubated with 5 c.c. of normal serum from the guinea- 

 pig at 37 for from one to twenty-four hours and then centri- 

 fuged. Many tubes may be employed and the supernatant 

 fluid from these mixed. From 3 to 5 c.c. of this fluid injected 

 intravenously into a guinea-pig of about 250 grams kills with 

 typical anaphylactic symptoms in from three to five minutes. 

 Even 0.1 c.c. of the agar solution furnishes enough poison 

 to kill. When the amount of agar solution employed is 

 greater than 1 c.c. or less than 0.1 the amount of poison 

 formed is, as a rule, not sufficient to kill, but may induce 

 anaphylactic symptoms of varying intensity. When the 



1 Zeitsch. f. Immunitatsforschung, 1913, xvii, 506. 



2 Compt. rend. Soc. biol., 1913, Ixxiv, No. 5. 



3 Zeitsch. f. Immunitatsforschung, 1913, xvii, 478. 

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