Pastorello E A, Farioli L, Pravettoni V, Ortolani C, Ispano M, Monza M, Baroglio C, Scibola E, Ansaloni R, Incorvaia C, Conti A
Allergy Center, III Department of General Medicine, Ospedale Maggiore IRCCS, Milan, Italy.
J Allergy Clin Immunol. 1999 Mar;103(3 Pt 1):520-6. doi: 10.1016/s0091-6749(99)70480-x.
Allergy to fresh fruits and vegetables is mostly observed in subjects with pollinosis, especially from birch, because of cross-reacting allergens in vegetable foods and pollens. However, allergic reactions to fruits, specifically Rosaceae fruits, have been reported in subjects without pollinosis.
This study evaluated the pattern of IgE reactivity, identifying the allergen responsible in 2 groups of patients with oral allergy syndrome to peach with or without birch pollinosis.
The allergenic components of peach were detected by SDS-PAGE and immunoblotting. The major peach allergen was purified by HPLC with a cation-exchange column followed by gel filtration chromatography. Its IgE-binding capacity and its homology with the protein of the crude extract were demonstrated by immunoblotting inhibition techniques. To better characterize this allergen, periodic acid-Schiff stain and isoelectrofocusing were used. The amino acid sequencing was done with a gas-phase sequencer.
SDS-PAGE and immunoblotting of the 15 patients allergic to peach, 8 without and 7 with birch pollinosis, showed that they all recognized a protein with a molecular weight of 9 kd. This was the only allergen recognized by patients not sensitized to pollen, whereas the birch pollen-sensitive patients had IgE binding to other allergenic proteins at higher molecular weights. The purified 9-kd protein retained its IgE-binding capacity, was negative to periodic acid-Schiff stain, and had an isoelectric point value of greater than 9. A search in the Swiss Prot Bank showed this was a lipid transfer protein, belonging to a group of molecules involved in the defensive system of plants.
The major allergen of peach is a 9-kd protein belonging to the group of lipid transfer proteins. This is the only allergen recognized by patients allergic to peach but not sensitized to birch pollen.
对新鲜水果和蔬菜的过敏大多见于花粉症患者，尤其是桦树花粉症患者，这是因为植物性食物和花粉中存在交叉反应性过敏原。然而，在无花粉症的患者中也有对水果，特别是蔷薇科水果过敏反应的报道。
本研究评估了两组对桃子有或无桦树花粉症的口腔过敏综合征患者的IgE反应模式，确定了相关过敏原。
通过SDS-PAGE和免疫印迹法检测桃子的过敏原成分。用阳离子交换柱HPLC随后进行凝胶过滤色谱法纯化主要的桃子过敏原。通过免疫印迹抑制技术证明其IgE结合能力及其与粗提物蛋白质的同源性。为更好地表征该过敏原，使用了过碘酸-希夫染色和等电聚焦。用气相测序仪进行氨基酸测序。
对15例对桃子过敏的患者（8例无桦树花粉症，7例有桦树花粉症）进行SDS-PAGE和免疫印迹分析，结果显示他们均识别出一种分子量为9kd的蛋白质。这是未对花粉致敏患者唯一识别的过敏原，而对桦树花粉敏感的患者IgE与其他分子量更高的过敏原蛋白结合。纯化的9kd蛋白保留了其IgE结合能力，过碘酸-希夫染色呈阴性，等电点值大于9。在瑞士蛋白质数据库中搜索显示这是一种脂质转移蛋白，属于参与植物防御系统的一组分子。
桃子的主要过敏原是一种属于脂质转移蛋白组的9kd蛋白质。这是对桃子过敏但未对桦树花粉致敏患者唯一识别的过敏原。
