昆蟲(chóng)刺蟄引起的過(guò)敏反應(yīng)是醫(yī)學(xué)上的一個(gè)重要的病癥，除了導(dǎo)致紅腫,、瘙癢等癥狀外,，全身性過(guò)敏反應(yīng)的發(fā)生甚至可能導(dǎo)致病人死亡。刺蟄的昆蟲(chóng)主要是昆蟲(chóng)綱膜翅目的成員,，包括胡蜂,、黃蜂等。但也有部分昆蟲(chóng)包括牛虻,、斑虻,、獵蝽等，會(huì)導(dǎo)致過(guò)敏性反應(yīng),。長(zhǎng)期以來(lái),，世界多個(gè)實(shí)驗(yàn)室都對(duì)牛虻和胡蜂導(dǎo)致的過(guò)敏反應(yīng)進(jìn)行了研究，并提出了胡蜂牛虻過(guò)敏交叉反應(yīng)綜合癥的存在,，但一直沒(méi)有找到直接的醫(yī)學(xué)證據(jù),。
近期，中國(guó)科學(xué)院昆明動(dòng)物研究所賴(lài)仞研究員領(lǐng)導(dǎo)的研究團(tuán)隊(duì)從牛虻唾液腺中分離和識(shí)別了兩個(gè)天然的過(guò)敏原分子Tab a 1和Tab a 2,，并收集了37例牛虻叮咬過(guò)敏病人的血清,，和3例胡蜂過(guò)敏病人的血清，檢測(cè)了這兩個(gè)分子與病人血清IgE的結(jié)合情況,。研究發(fā)現(xiàn),，Tab a 1和Tab a 2與病人血清IgE反應(yīng)呈現(xiàn)出80-90％的陽(yáng)性率，并且可以劑量依賴(lài)的方式競(jìng)爭(zhēng)性抑制病人血清IgE與牛虻唾液腺總蛋白的結(jié)合,。
這是世界上從牛虻唾液腺中首次鑒定出天然過(guò)敏原的首次報(bào)道,，該研究結(jié)果為胡蜂牛虻過(guò)敏綜合癥提供了直接的證據(jù)，對(duì)昆蟲(chóng)刺蟄過(guò)敏性反應(yīng)的診斷和治療具有重要的意義,。(生物谷Bioon.net)
生物谷推薦原文出處：
Allergy DOI:10.1111/j.1398-9995.2010.02435.x
Purification and characterization of two new allergens from the salivary glands of the horsefly, Tabanusyao
D. Ma 1,2*, Y. Li 1,2*, J. Dong 3*, S. An 2,4 , Y. Wang 1,2 , C. Liu 1,2 , X. Yang 1,2 , H. Yang 1,2 , X. Xu 1 , D. Lin 3 & R. Lai 1
1 Kunming Institute of Zoology, Chinese Academy of Sciences, Kunming, Yunnan, China ; 2 Graduate School of the Chinese Academy of Sciences, Beijing, China ; 3 School of Life Science and Technology, China Pharmaceutical University, Nanjing, China ; 4 School of Life Sciences, University of Science and Technology of China, Hefei, Anhui, China
Background: Horsefly bite can cause allergic reactions in humans. There is no information about allergenic horsefly proteins.
Objectives: The current work aims to purify and characterize IgE-binding proteins from horsefly salivary glands.
Methods: Two IgE-binding proteins, Tab a 1 and Tab a 2 with molecular weight of 26 and 35 kd, respectively, were purified and characterized from 60 000 pairs of horsefly salivary glands of Tabanus yao, respectively. Their primary sequences were determined by Edman degradation and cDNA cloning. Their allergenicity was examined using enzyme-linked immunosorbent assay (ELISA), ELISA inhibition tests, and immunoblots.
Results: Immunoblotting demonstrated IgE binding by 32 and 34 of 37 (86.5% and 91.8%) subjects' sera to Tab a 1 and Tab a 2, respectively. They were identified as an antigen 5-related (Ag 5) protein and hyaluronidase, respectively. ELISA inhibitions of serum IgE reactivity to the horsefly salivary gland extract (SGE) using purified Tab a 1 and Tab a 2 were significant (about 45%). In addition, these proteins showed some IgE-binding capacity to sera of subjects with wasp sting allergy.
Conclusions: We have first identified and characterized two IgE-binding proteins, Tab a 1, an Ag 5-like protein and Tab a 2, a hyaluronidase, from the horsefly salivary glands. They appear to be of importance for the allergic reactions induced by horsefly bite. These allergens are thus not only found in stinging but also found in hematophagous insects. These results also provided support for the presence of the so-called wasp-horsefly syndrome (WHS).
