van Odijk J, Peterson C G B, Ahlstedt S, Bengtsson U, Borres M P, Hulthén L, Magnusson J, Hansson T
Department of Clinical Nutrition, Faculty of Medicine, Sahlgrenska Academy at Goteborg University, Gothenburg, Sweden.
Int Arch Allergy Immunol. 2006;140(4):334-41. doi: 10.1159/000093769. Epub 2006 Jun 2.
Objective assessment of inflammatory reactions in the gastrointestinal tract could be useful in the diagnosis of food hypersensitivity. The aim of the present study was to investigate the involvement of eosinophils and mast cells in the inflammatory response of patients with food hypersensitivity before and after food challenges.
Eleven patients (4 with IgE-mediated allergy and 7 without) with food hypersensitivity and positive double-blind, placebo-controlled food challenge were subjected to food challenge in a single-blinded fashion. Four subjects with no known food hypersensitivity were recruited as controls. Placebo was given after a 1-week washout period followed by an active dose. Stool, urinary and serum samples were collected and symptoms were recorded in a diary. Fecal samples were analyzed for eosinophil protein X (F-EPX) and tryptase; urinary samples for EPX (U-EPX) and leukotriene E4 (U-LTE4) and serum samples were analyzed for eotaxin and food-specific IgE antibodies.
Patients with IgE-mediated food allergy had increased levels of F-EPX compared to controls and tended to have lower serum levels of eotaxin compared to non-allergic patients and controls. U-LTE4 was significantly higher in allergic patients compared to non-allergic patients after challenge. Moreover, F-EPX correlated to U-LTE4 (p = 0.011). Reported symptoms, abdominal pain, distension, flatulence and nausea were similar in the allergic and non-allergic patients.
The results strongly indicate that eosinophils are activated in the gastrointestinal tract of food-allergic patients but not in patients with non-allergic food hypersensitivity. Due to the inconsistent pattern of symptoms after placebo and active food challenge, it was not possible to relate the levels of inflammation markers to the recorded symptoms.
胃肠道炎症反应的客观评估可能有助于食物过敏的诊断。本研究的目的是调查嗜酸性粒细胞和肥大细胞在食物激发前后食物过敏患者炎症反应中的作用。
11例食物过敏且双盲、安慰剂对照食物激发试验阳性的患者（4例为IgE介导的过敏，7例非IgE介导的过敏），采用单盲方式进行食物激发试验。招募4例无已知食物过敏的受试者作为对照。经过1周的洗脱期后给予安慰剂，随后给予活性剂量。收集粪便、尿液和血清样本，并通过日记记录症状。分析粪便样本中的嗜酸性粒细胞蛋白X（F-EPX）和类胰蛋白酶；尿液样本中的EPX（U-EPX）和白三烯E4（U-LTE4）；血清样本中的嗜酸性粒细胞趋化因子和食物特异性IgE抗体。
与对照组相比，IgE介导的食物过敏患者的F-EPX水平升高，与非过敏患者和对照组相比，其血清嗜酸性粒细胞趋化因子水平往往较低。激发试验后，过敏患者的U-LTE4显著高于非过敏患者。此外，F-EPX与U-LTE4相关（p = 0.011）。过敏患者和非过敏患者报告的症状，如腹痛、腹胀、肠胃胀气和恶心相似。
结果强烈表明，食物过敏患者胃肠道中的嗜酸性粒细胞被激活，而非过敏性食物过敏患者则未被激活。由于安慰剂和活性食物激发试验后症状模式不一致，因此无法将炎症标志物水平与记录的症状联系起来。
