On the Dialysability of Proteins.

Abstract

In several of his recent studies upon atopic hypersensitiveness (Idiosynkrasie), W. Jadassohn 1 , 2 has reported the fact that the excitants of the hypersitiveness (to celery, guinea pig serum and egg white) are dialysable. In the dialysate from egg white, the presence of protein could not be demonstrated with any of the chemical tests for protein. From these observations, this author draws the conclusion that the atopens in the materials mentioned are not proteins and not antigens. He considers them therefore as belonging in the group of the haptens (Landsteiner).

Jadassohn did not directly test any of the dialysates for the presence of antigen, and he seems therefore to base his conclusion that the dialysable atopens are not antigenic, upon the universally accepted assumption that the antigens are colloids and therefore not dialysable.

Jadassohn does not state in any of his reports, what kind of membrane he used in his experiments.

I have used both animal membrane (fish bladder), and the collodion sac, and with these I have been able easily to confirm Jadassohn's results with pseudoglobulin, albumin, and mucoid of egg white. Other materials were not used. Each sac was tested for leakage, under moderate pressure in a dark room, with hand lens.

The dialysates collected in distilled water were concentrated by fanning to about 1/500 volume and tested with 3 antisera, which were quite specific for the 3 proteins mentioned above. All 3 proteins could be identified in the concentrated dialysates. In 2 instances, the concentration of the dialysed substance was sufficient to permit the chemical demonstration of biuret.

In one experiment with ovo-mucoid, the dialysed solution (5-10%) was quantitatively compared with the concentrated dialysate, with the specific precipitation method, and the biuret test (colorimetric); with the former, the concentrated dialysate appeared about 1/8 as strong as the dialysed solution, and, with the latter, the ratio was 1-7.