Electrophoretic fractionation of soluble antigenic proteins from the seed ofRicinus communis (castor bean)

Abstract

A water‐soluble, heat‐stable protein component of castor seed meal was subjected to paper‐strip electrophoresis in buffers of different chemical composition, pH values, and ionic strengths. It was shown that phosphate buffer at pH 7.4 to 8.0 and an ionic strength of approximately 0.05 gave a sharp resolution of castor seed proteins into bands which would bind bromophenol blue. Spies' Allergen CB‐1A was shown to be resolved into six or more components at pH 8.0. Each major component band was found to be antigenic by passive cutaneous anaphylaxis in guinea pigs that were sensitized with rabbit antiserum to the crude castor seed protein preparation. Five bands were shown to be allergenic to humans. The results appear to support earlier observations (1,2,10) that castor bean seed allergenicity to humans may be caused by more than one antigen in Spies' Allergen CB‐1A and possibly by other antigens present in the seed but either absent from, or greatly reduced in concentration in, allergen CB‐1A. The water‐soluble component of Altschul's active castor seed lipase was resolved into eight component bands, two of which did not appear in the electrophotograms of the heat‐processed preparation CB‐1A S.R.I.

Evidence That the Castor Bean Allergens Are the Albumin Storage Proteins in the Protein Bodies of Castor Bean

“…Potent allergens of protein nature in the castor bean have been studied decades ago by Spies and coworkers (7-1 1; see reviews 1,8) and more recently by other investigators (2,4,5). These castor bean allergens, studied intensively by Spies' group, are a group of microheterogeneous proteins of low mol wt with closely similar chemical properties.…”

Castor Bean Allergy as Cross-Reactive Hypersensitivity to the Spurges (Euphorbiaceae): Absence of Reaction to Chlorogenic Acid in Primary Allergy to Castor Beans

“…Two monkeys that were challenged by direct skin-prick test with a 1 % concentration of chlorogenic acid gave no reactions in any of the sites sensitized by sera from the 26 castor bean-sensitive patients first studied (13). These monkeys then were challenged with a 5% solution of the solids extracted from green coffee, and again there were no reactions.…”

“…Four of them were employees of an American castor bean as Cross-Reactive Hypersensitivity to the Spurges 227 processing factory and were known to be primarily allergic to castor bean pomace (10). The other 29 individuals were townspeople of Marseille, France, and allergy patients of Pa n z a n i. Reaginic sera were available from 26 other French patients who had been subjects of previous studies (13) and none of whom had received hyposensiti zation treatments for castor bean (or coffee) allergy. The 26 sera had all been tested several times by the passive allergy transfer test of L a y t o n and shown to be reaginic to castor bean seed (12).…”

“…Castor bean protein was prepared by repeated alcoholic preci pitation from the hot water extract of defatted castor bean flour as previously described (13). The resulting partially purified seed pro tein, designated as "CB-WU", was non-toxic, non-irritating, and completely water-soluble.…”

Systemic Allergic Shock Induced in Monkeys Passively Sensitized by Intravenous Injection of Human Allergy Sera

“…Evans Blue dye in isotonic saline at a dosage of 1.5 ml per kilogram of body weight. Each monkey then was tested by scratch-or skinprick test (5) with a commercial extract of mixed spring grass pol lens, and then with dilute extract of ricin-frce castor bean seed protein CB-WU prepared by our method (6). After conducting and reading the skin-scratch tests we then gave the monkey an iv.…”