Purification, identification and characterization of the major allergen from Linnaeus / 中国免疫学杂志

ABSTRACT

Objective:To purify and characterize the major antigenic components of sand swimming crab,and provide theoretical evidences for the research of standardization of allergenic vaccine.Methods:The crude extract of Linnaeus was prepared using classical method, and electrophoresis of SDS-PAGE was used to separate the proteins of each group. The allergen proteins of 26 crab were identified using Western blot. To distinguish between the primary allergen proteins and secondary allergen proteins, FPLC(Gel Chromatography and ion exchange chromatography) was used to filtrate and identify the allergen protein.Results:SDS-PAGE analysis revealed that sand swimming crab proteins were composed of at lease 9 discrete protein bands, which molecular weight ranging from 13 000 to 90 000. Major bands were of 20 900, 24 200, 27 100, 29 200, 33 700, 38 900, 48 700, 74 700, 89 100 respectively. Western blot assay indicated that the crude extract reacted with sera obtained from 26 crab allergenic subjects and contained 5 allergen bands altogether, and the bands of 74 400 and 48 700 were the major allergenic components. The positive rates of the two major allergen proteins were both 100%, indicating the allergenic components maintained the immunocompetence after yielding from chromatography.Conclusion:The 74 400 and 48 700 bands are the major allergens of sand swimming crab. The major allergen proteins can be purified by chromatography.