Studies on Anaphylaxis with the Products of Peptic Digestion of Proteins. II.

Abstract

In the experiments reported previously 1 material was used for the peptic digestion consisting mainly of egg albumin but also containing egg globulin. Since it was thought that possibly the latter was responsible for the effects observed, experiments were made with preparations of egg globulin. The results were in agreement with the former experiments in that the animals sensitized with the peptic digestion products were more sensitive to these than to unchanged globulin and vice versa. This result was especially pronounced in one batch of guinea pigs, the lethal intravenous dose for the animals sensitized with the digestion product being 1 cc. of a 1-2% solution of the digested material∗ and about 1 cc. of a 0.2% solution of globulin, while the respective values for the animals sensitized with globulin were about 4% and 0.0125%. In another batch of animals this difference was still definite but less considerable. But, after precipitating a 5% solution of the digestion product with an equal volume of 10% trichloracetic acid and precipitating the supernatant fluid with alcohol the resulting substance was much more toxic for the guinea pigs sensitized with the digested material (lethal dose 0.5%) than for those sensitized with globulin (lethal dose 4% or more). Similar results were obtained by sensitizing with digested heat-coagulated egg globulin. These animals were killed by an i. v. injection of 1 cc. of 0.25% to 0.125% of the digestion product after fractionation with trichloracetic acid and by 1 cc. of a 0.1% solution of unchanged globulin.

In some cases, but irregularly, the animals sensitized with peptic products succumbed to injections of 1% ovomucoid. This substance, however, can hardly be essential for the results reported since digested products of heat-coagulated globulin were more active in producing shock than those of non-coagulated globulin in animals sensitized with digestion products of the latter preparation, and also on account of the results of experiments with guinea pigs sensitized with ovomucoid itself.