Fractionation and Characterization of Allergens Extracted from Eggs of Schistosoma japonicum

Abstract

Allergenic components were partially purified from the crude extract of eggs of Schistosoma japonicum by gel filtration on Sephadex G-200 and ion-exchange chromatography on DEAE-Sephadex A-50. Allergenic activity was assayed by the Prausnitz-KÜstner type skin test with infected mouse sera and radioallergosorbent test with human sera. 5. japonicum egg allergens (JEAL) showed single and three allergenic peaks, by isoelectrofocusing (pI =4.8) and polyacrylamide gel electrophoresis, respectively. The molecular weights of JEAL were calibrated 30,000–200,000 by gel filtration. JEAL were adsorbed on the affinity columns of concanavalin A, Lentil lectin and partially wheat germ lectin. JEAL lost their allergenic activity by 0.1 M periodate oxidation; however, they were resistant to heating (100°C, 60 min), urea and guanidine. We suppose that the carbohydrate of JEAL is important to the allergenic determinant.