Detoxification of and the Immunity Production to Ricin by Sodium Ricinoleate.

Abstract

The works of Larson 1 and his co-workers on sodium ricinoleate suggested the possibility of its use with other toxins such as those of plants and animals. Ricin was chosen first because the author, during the studies on the chemical basis of its toxicity, found that certain chemical and physical treatments could not only detoxify the toxin, but would produce an immunity to ricin in the animals when so treated. 2

The ricin was prepared by the method of Osborne, Mendel and Harris. 3 A fresh aqueous solution was made for each experiment. It was clear and light yellow in color when concentrated.

The sodium ricinoleate was kindly furnished by Professor Larson. A 10 per cent stock solution was made in distilled water in a pyrex flask. It was light yellow in color.

These two solutions were mixed in such proportions as to make about 3 per cent of sodium ricinoleate in final volume. When the solution of ricin, containing 2,000 lethal doses for a rabbit in 5 to 10 cubic centimeters, was mixed with the sodium ricinoleate, it immediately became milky and opaque.

The mixed solutions were allowed to stand for one hour and then were injected into rabbits subcutaneously. The doses of the toxin employed varied over a rather wide range. The typical results obtained are given in the following table.

An inspection of the table makes it obvious that it is possible to inject a large number of lethal doses of ricin, if mixed with sodium ricinoleate, without killing the animal. The animals injected with 400 or more lethal doses of the treated rich always showed an ulcer at the site of the injection. The minimum dose that will cause an ulcer has not been determined.