Methods The allergenic proteins, Dff F3 and Der f ⅲ ( well known allergen) from the whole culture extract of Dermatophagoides farinae were purified by chromatography and sedimentation techniques. Allergic activities of both proteins were identified by skin prick test and RAST. 方法应用层析介质及蛋白质沉淀技术从螨代谢分泌物中分离、纯化粉尘螨变应原DffF3及国际公认的变应原DerfⅢ,经临床检测和放射性变应原吸附实验(RAST)鉴定其变应原性。