Würtzen P A, van Neerven R J, Arnved J, Ipsen H, Sparholt S H
ALK ABELLO Group, Hørsholm, Denmark.
J Allergy Clin Immunol. 1998 Feb;101(2 Pt 1):241-9. doi: 10.1016/S0091-6749(98)70389-6.
Pollinosis, caused by grasses of the Poaceae family, is a problem worldwide. The relative importance of grass groups 1 and 5 major allergens is well established. However, not much is known about the recognition of these allergens by T cells and whether this T-cell reactivity correlates with skin reactivity and serum IgE levels.
The aim of this study was to characterize the cross-reactive, grass allergen-specific T-cell responses from patients allergic to grass and nonatopic individuals and to investigate whether these responses correlate with grass-specific IgE and skin reactivity.
Skin prick test wheal areas and grass-specific serum IgE levels were determined in all patients (n = 21) and nonallergic control donors (n = 20). Peripheral blood mononuclear cells were isolated and stimulated with grass allergen extracts (Phleum pratense, Poa pratensis, Lolium perenne) and immunoaffinity-purified group 5 allergens, and the production of type 1 and type 2 cytokines was determined in the patient group.
Donors allergic to grass showed increased T-cell-proliferative responses to grass allergens compared with nonatopic control subjects. We find it interesting that the magnitude of the patients' T-cell responses could not be correlated with the individual skin prick test areas and specific serum IgE levels, and several patients with allergies to grass had group 5-specific T-cell responses in the absence of group 5-specific IgE. The absence of a correlation between T-cell proliferation and IgE levels or skin prick test results may in part be explained by the finding that patients predominantly produced IL-5 in response to Phl p 5, the major allergen, and predominantly IFN-gamma in response to Phl p extract. In general, all donors responded equally well to all three grasses. Additional experiments with Phl p 5-specific T-cell lines indicated that the equal proliferation of peripheral blood mononuclear cells to all three species is the direct result of cross-reactivity.
Grass allergen-specific T-cell responses are highly cross-reactive, and patients with allergies exhibit higher responses than nonallergic donors, suggesting that T cells are involved in the allergic reaction to grass group 5 allergens. However, group 5-specific T-cell responses are also found in donors without group 5-specific IgE, and the patients' grass-specific T-cell responses and cytokine production do not correlate to skin reactivity or to concentrations of grass-specific IgE.
由禾本科草类引起的花粉症是一个全球性问题。第1组和第5组草类主要过敏原的相对重要性已得到充分证实。然而，关于T细胞对这些过敏原的识别以及这种T细胞反应性是否与皮肤反应性和血清IgE水平相关，目前所知甚少。
本研究的目的是表征对草类过敏患者和非特应性个体的交叉反应性、草类过敏原特异性T细胞反应，并研究这些反应是否与草类特异性IgE和皮肤反应性相关。
测定所有患者（n = 21）和非过敏对照供体（n = 20）的皮肤点刺试验风团面积和草类特异性血清IgE水平。分离外周血单个核细胞，用草类过敏原提取物（早熟禾、草地早熟禾、多年生黑麦草）和免疫亲和纯化的第5组过敏原进行刺激，并在患者组中测定1型和2型细胞因子的产生。
与非特应性对照受试者相比，对草类过敏的供体对草类过敏原的T细胞增殖反应增强。我们发现有趣的是，患者的T细胞反应强度与个体皮肤点刺试验面积和特异性血清IgE水平无关，并且一些对草类过敏的患者在没有第5组特异性IgE的情况下有第5组特异性T细胞反应。T细胞增殖与IgE水平或皮肤点刺试验结果之间缺乏相关性，部分原因可能是发现患者对主要过敏原Phl p 5主要产生IL-5，而对Phl p提取物主要产生IFN-γ。一般来说，所有供体对所有三种草的反应都同样良好。对Phl p 5特异性T细胞系的进一步实验表明，外周血单个核细胞对所有三种草的同等增殖是交叉反应的直接结果。
草类过敏原特异性T细胞反应具有高度交叉反应性，过敏患者的反应高于非过敏供体，这表明T细胞参与了对草类第5组过敏原的过敏反应。然而，在没有第5组特异性IgE的供体中也发现了第5组特异性T细胞反应，并且患者对草类的特异性T细胞反应和细胞因子产生与皮肤反应性或草类特异性IgE浓度无关。
