Division of Allergology, Department of Rheumatology, Clinical Immunology and Allergology, Inselspital, University of Bern, Switzerland.
Allergy. 2012 Feb;67(2):280-5. doi: 10.1111/j.1398-9995.2011.02744.x. Epub 2011 Nov 10.
Patients with birch pollen allergy (major allergen: Bet v 1) have often an associated oral allergy syndrome (OAS) to apple, which contains the cross-reactive allergen Mal d 1. As successful birch pollen immunotherapy does not consistently improve apple related OAS symptoms, we evaluated whether regular apple consumption has an effect on OAS and immune parameters of Mal d 1 or Bet v 1 allergy.
A total of 40 patients with a clear history of birch pollen rhinoconjunctivitis and associated OAS to apple were included in an open, randomized, controlled clinical trial: 27 patients consumed daily defined amount of apple (1-128 g), doubling the amount every two to three weeks, while 13 patients remained untreated. Primary endpoint was the proportion of patients that achieved tolerance to at least 128 g of apple at the end of the study after 8 months. Exploratory endpoints were questionnaire about cross-reactive food and pollen allergy symptoms, conjunctival provocation test with birch pollen and Bet v 1, and in vitro tests (tIgE, sIgE, and IgG4 to Mal d 1 and Bet v 1; basophil activation test with both allergens).
Seventeen of 27 patients in active group and none of 13 patients in control group (P = 0.0001) could tolerate a whole apple after the intervention. However, differences in endpoints reflecting systemic immune reactivity did not reach statistical significance.
In patients with OAS to apple, tolerance can be safely induced with slowly, gradually increasing consumption of apple. However, the observation of a relapse after discounting of apple consumption and absence of immunologic changes suggest that induced tolerance is only transient.
桦树花粉过敏（主要过敏原：Bet v 1）的患者常伴有苹果的口腔过敏综合征（OAS），苹果中含有交叉反应过敏原 Mal d 1。由于成功的桦树花粉免疫疗法并不能持续改善与苹果相关的 OAS 症状，我们评估了定期食用苹果是否会对 Mal d 1 或 Bet v 1 过敏的 OAS 和免疫参数产生影响。
共有 40 名明确有桦树花粉性鼻炎和苹果相关 OAS 病史的患者纳入一项开放、随机、对照临床试验：27 名患者每天摄入一定量的苹果（1-128 g），每两到三周增加一倍，而 13 名患者未接受治疗。主要终点是在 8 个月后研究结束时至少有 128 g 苹果耐受的患者比例。探索性终点是关于交叉反应性食物和花粉过敏症状的问卷、桦树花粉和 Bet v 1 的结膜激发试验以及体外测试（Mal d 1 和 Bet v 1 的 tIgE、sIgE 和 IgG4；两种过敏原的嗜碱性粒细胞激活试验）。
在活跃组的 27 名患者中有 17 名，而对照组的 13 名患者中没有（P = 0.0001）在干预后可以耐受整个苹果。然而，反映系统免疫反应性的终点差异没有达到统计学意义。
在对苹果有 OAS 的患者中，可以安全地通过缓慢、逐渐增加苹果的摄入量来诱导耐受。然而，考虑到停止食用苹果后会复发以及免疫变化的缺失，提示诱导的耐受只是暂时的。
