The effect of dye “blockade” on anaphylaxis and antibody formation in the guinea pig.

Abstract

The experiments reported here are a continuation of the work of Gay and Clark, 1 on the effect of endothelial blockade in antibody production.

In the present work guinea pigs were saturated with trypan blue (daily 1 cc. injections of a 1 per cent solution of the dye in distilled water). After ten injections the animals received sheep cells, according to the method of Lewis and Loomis. 2 The trypan blue injections were then continued until the first bleeding. The results are shown in the following table. Each group represents eight to ten animals.

In practically every case the pigs treated with trypan blue produced less hemolysin than did the controls. These figures indicate a gradual rise in the titre in the trypan blue animals, but in four cases the blood consistently contained no hemolysin, even after the twenty-second day.

These results are in (complete agreement with those published by Gay and Clark.

Experiments were next tried to see what relation trypan blue blockade bore to anaphylaxis. Sensitized guinea pigs were given several injections of trypan blue. On reinjection of antigen all responded vigorously. Normal animals, injected with trypan blue for a period of ten days, sensitized with egg white and then further treated with trypan blue for two weeks, responded anaphylactically on reinjection of antigen. Thus it is clear that endothelial blockade, at least in guinea pigs, neither acts as an antisensitizer, nor as a desensitizer.

There appears, then, to be a different mechanism involved in the production of anaphylactic sensitization and the formation of antisheep hemolysin in guinea pigs.