Department of Pediatrics, University of Texas Medical Branch, 301 University Blvd., Galveston, TX, 77555-0366, USA.
Isis Clinical Research, LLC, 6836 Austin Center Blvd., Ste 180, Austin, TX, 78731, USA.
Mol Immunol. 2019 Jul;111:83-86. doi: 10.1016/j.molimm.2019.04.007. Epub 2019 May 6.
Mountain cedar pollen is recognized as a major cause of seasonal hypersensitivity in the US. We describe here that a subgroup of these patients also suffer from pollen food allergy syndrome (PFAS).
We performed this study to determine the frequency of PFAS among patients with mountain cedar hypersensitivity.
We performed mail-out/telephone surveys of 800 mountain cedar-sensitive patients in Austin, TX. The subjects for this survey were selected by telephone screening, and skin and serologic testing. We performed immunoblot inhibition assay and mass spectrometry (MS) to identify the allergens that cause PFAS.
Of the 28 patients with suspected food allergies, 15 had clinical manifestations of PFAS. Eleven of them had positive skin tests to tomato, six to banana, and one to apple. The subjects with PFAS have stronger cutaneous and in vitro reactivity to cedar pollen. The intensities of the tomato and banana reactivity were correlated with the cedar reactivity. The results of the ImmunoCAP inhibition experiments demonstrated a strong cross-reactivity between IgE antibodies to cedar pollen and fruits. This suggested that their primary sensitization was to cedar pollen, since absorption with cedar pollen extract strongly inhibited reactivity to each of the fruits, while the absorption with tomato extract did not significantly inhibit IgE binding to cedar extract. We determined that polygalacturonase 2 A (PG2 A) in tomato is the cause of PFAS.
This is the first report of a PFAS in patients with mountain cedar pollinosis. Sensitivity to tomato, banana, and apple should be considered in cedar-sensitive patients.
山艾树花粉被认为是美国季节性过敏的主要原因。我们在此描述，这些患者中的一个亚组还患有花粉食物过敏综合征（PFAS）。
我们进行这项研究是为了确定山艾树过敏患者中 PFAS 的频率。
我们对德克萨斯州奥斯汀的 800 名山艾树敏感患者进行了邮件/电话调查。通过电话筛选、皮肤和血清学测试选择了这些调查的对象。我们进行了免疫印迹抑制试验和质谱（MS）分析，以确定引起 PFAS 的过敏原。
在 28 名疑似食物过敏的患者中，有 15 名出现了 PFAS 的临床症状。其中 11 人对番茄呈阳性皮肤试验，6 人对香蕉呈阳性，1 人对苹果呈阳性。有 PFAS 的患者对山艾花粉的皮肤和体外反应性更强。番茄和香蕉反应性的强度与山艾花粉反应性相关。免疫 CAP 抑制实验的结果表明，山艾花粉和水果的 IgE 抗体之间存在强烈的交叉反应性。这表明他们的主要致敏原是山艾花粉，因为山艾花粉提取物的吸收强烈抑制了对每种水果的反应，而番茄提取物的吸收并没有显著抑制 IgE 与山艾提取物的结合。我们确定番茄中的多聚半乳糖醛酸酶 2A（PG2A）是引起 PFAS 的原因。
这是山艾树花粉过敏患者中首次报告 PFAS。山艾树敏感患者应考虑对番茄、香蕉和苹果敏感。
