士鋒生物咨詢：大胡蜂毒素引起速發型過敏反應機制

翅目昆蟲的叮咬是引起速發型過敏反應的三大主要誘因之一。能引起速發型過敏反應的常見昆蟲有蜜蜂、胡蜂、牛虻、蚊子等。大胡蜂作為一種個體較大，毒素富含過敏原，常群起攻擊人的昆蟲，其危害尤為嚴重。大胡蜂叮咬后的常見癥狀有紅腫、灼痛、顫抖、支氣管收縮、甚至過敏性休克危及生命。胡蜂（vespids）種類多達24種，由于各種條件的限制，目前人們僅對其中一種胡蜂（Vespa crabro）毒素的過敏原進行了初步的研究。

為了進一步深入了解胡蜂毒素過敏原組成成分，中國昆明動物研究所賴仞研究員的團隊在對牛虻過敏原分離純化鑒定的經驗基礎之上，通過整合色譜層析和免疫雜交等技術發展了一套有效分離純化識別胡蜂毒素過敏原的方法。應用該方法，我們從大胡蜂（vespa magnifica）毒素中分離純化到兩種新的過敏原Vesp ma5和Vespa ma2，它們分別是25-KDa的抗原5蛋白和35-KDa的透明質酸酶（Hyaluronidase）。IgE immunoblot檢測顯示：Vesp ma5和Vespa ma2對蜂中毒過敏病人血清的IgE的陽性反應率為91.0%和93.9%，對牛虻過敏病人血清IgE陽性反應率也高達86.5%和91.8%。通過Elisa inhibition檢測顯示：Vesp ma5和Vespa ma2對蜂毒粗樣與蜂中毒過敏病人血清IgE結合的zui大抑制率分別為39.5%和39.4%，對牛虻唾液腺粗樣與牛虻過敏病人血清IgE結合的zui大抑制率分別為25.3%和23.8%。刺檢測顯示：Vesp ma5和Vespa ma2對蜂中毒過敏病人的陽性反應率分別為73%和80%。以上結果從不同方面證明了Vesp ma5和Vespa ma2為大胡蜂（vespa magnifica）毒素中兩類主要過敏原，同時也為胡蜂牛虻綜合征從另一角度提供了有力的證據。

Purification and Characterization of Two New Allergens from the Venom of Vespa magnifica

Su An1,2,5#, Lingling Chen4#, Ji-Fu Wei3#, Xuening Yang1,5#, Dongying Ma1, Xuemei Xu4, Xueqing Xu1, Shaoheng He3*, Jia Lu1*, Ren Lai1*

Due to poor diagnostic facilities and a lack of medical alertness, allergy to Vespa wasps may be underestimated. Few allergens have been identified from Vespa wasps. Possible native allergen proteins were purified from the wasp venoms （WV） （Vespa magnifica Smith） by gel filtration, ion exchange chromatography, respectively. Their sequences were determined by Edman degradation and cDNA cloning. Their allergenicities were assayed by enzyme-linked immunosorbent assay inhibition tests （ELISA-IT）, immunoblots, and skin prick tests （SPTs）. Their cross allergencities with Tab y 2 and Tab y 5 purified from the horsefly （Tabanus yao Macquart） were also determined. Two native allergens were identified from the WV, respectively. They are a 25-KDa antigen 5 protein （Ag5） （Vesp ma 5） and a 35-KDa hyaluronidase （Vesp ma 2）. They represented major allergens in Vespa magnifica by immunoblots and SPTs. ELISA inhibition of pooled sera IgE reactivity to both the WV and the horsefly salivary gland extracts （HSGE） using four purified allergens （Vesp ma 2, Vesp ma 5 and previously purified Tab y 2 and Tab y 5） was significant. Their cross allergenicities were confirmed by ELISA-IT, immunoblots, and SPTs. They represented the cross reactive allergens from wasp and horsefly and proved the so called wasp-horsefly syndrome.