Andersson Kerstin, Lidholm Jonas
Pharmacia Diagnostics AB, Uppsala, Sweden.
Int Arch Allergy Immunol. 2003 Feb;130(2):87-107. doi: 10.1159/000069013.
Grass pollens are one of the most important airborne allergen sources worldwide. About 20 species from five subfamilies are considered to be the most frequent causes of grass pollen allergy, and the allergenic relationships among them closely follow their phylogenetic relationships. The allergic immune response to pollen of several grass species has been studied extensively over more than three decades. Eleven groups of allergens have been identified and described, in most cases from more than one species. The allergens range from 6 to 60 kD in apparent molecular weight and display a variety of physicochemical properties and structures. The most complete set of allergens has so far been isolated and cloned from Phleum pratense (timothy grass) pollen. Based on the prevalence of IgE antibody recognition among grass pollen-sensitized individuals, several allergens qualify as major, but members of two groups, groups 1 and 5, have been shown to dominate the immune response to grass pollen extract. Isoform variation has been detected in members of several of the allergen groups, which in some cases can be linked to observed genetic differences. N-linked glycosylation occurs in members of at least three groups. Carbohydrate- reactive IgE antibodies have been attributed to grass pollen sensitization and found to cross-react with glycan structures from other allergen sources, particularly vegetable foods. Another cause of extensive cross-reactivity are the group 12 allergens (profilins), which belong to a family of proteins highly conserved throughout the plant kingdom and present in all tissues. Members of eight allergen groups have been cloned and expressed as recombinant proteins capable of specific IgE binding. This development now allows diagnostic dissection of the immune response to grass pollen with potential benefits for specific immunotherapy.
草花粉是全球最重要的空气传播过敏原来源之一。来自五个亚科的约20个物种被认为是草花粉过敏最常见的病因，它们之间的过敏原关系与其系统发育关系密切相关。在三十多年的时间里，对几种草类花粉的过敏免疫反应进行了广泛研究。已鉴定并描述了11组过敏原，大多数情况下来自多个物种。这些过敏原的表观分子量在6至60 kDa之间，具有多种物理化学性质和结构。迄今为止，已从梯牧草花粉中分离并克隆出最完整的一组过敏原。根据草花粉致敏个体中IgE抗体识别的普遍性，几种过敏原被认定为主要过敏原，但第1组和第5组中的成员已被证明在对草花粉提取物的免疫反应中占主导地位。在几个过敏原组的成员中检测到了同工型变异，在某些情况下，这可能与观察到的基因差异有关。至少三组的成员发生了N-糖基化。碳水化合物反应性IgE抗体与草花粉致敏有关，并被发现与其他过敏原来源（特别是植物性食物）的聚糖结构发生交叉反应。广泛交叉反应的另一个原因是第12组过敏原（肌动蛋白结合蛋白），它们属于在整个植物界高度保守且存在于所有组织中的一类蛋白质。八个过敏原组的成员已被克隆并表达为能够特异性结合IgE的重组蛋白。这一进展现在使得能够对草花粉的免疫反应进行诊断剖析，对特异性免疫疗法可能有益。
