Grote Monika, Swoboda Ines, Valenta Rudolf, Reichelt Rudolf
Institute of Medical Physics and Biophysics, University of Munster, Munster, Germany.
Int Arch Allergy Immunol. 2005 Apr;136(4):303-10. doi: 10.1159/000083975. Epub 2005 Feb 17.
Polygalacturonases were recently identified as important grass pollen allergens and designated group 13 allergens. The objective of the present study was to investigate the presence of group 13 grass pollen allergens in different grass species, their release and ultrastructural location in dry and hydrated grass pollen.
Nitrocellulose-blotted allergen extracts from 12 wild and cultivated grass genera were probed with a rabbit antiserum raised against purified recombinant timothy grass pollen allergen, Phl p 13. The release kinetics of Phl p 13 from timothy grass pollen hydrated for 0.5 min to 3 h were analyzed by immunoblotting. Phl p 13 was localized in dry and hydrated grass pollen grains by immunogold field emission scanning and transmission electron microscopy.
Group 13 allergens were detected in all 12 wild and cultivated grass genera representing the major subfamilies of the Poaceae. Ultrastructurally, the allergen was located in the wall and in the cytoplasm of timothy grass pollen grains. In the cytoplasm, Phl p 13 was associated with polysaccharide particles and as yet undescribed stacks of microtubule-like structures. After hydration in rain water, pollen grains expel cytoplasmic particles of respirable size containing Phl p 13, which becomes detectable in aqueous supernatants already after 0.5 min.
Group 13 allergens represent one set of marker allergens which specifically occur in pollen of the major grass subfamilies and are rapidly released in association with respirable particles after pollen hydration. They may be considered as environmental markers for grass pollen exposure and group 13-specific IgE antibodies as immunological markers for genuine grass pollen sensitization.
多聚半乳糖醛酸酶最近被鉴定为重要的禾本科花粉过敏原，并被指定为第13组过敏原。本研究的目的是调查不同禾本科植物中第13组禾本科花粉过敏原的存在情况，以及它们在干燥和水合禾本科花粉中的释放情况和超微结构定位。
用针对纯化的重组梯牧草花粉过敏原Phl p 13产生的兔抗血清，检测12个野生和栽培禾本科属的硝酸纤维素印迹过敏原提取物。通过免疫印迹分析Phl p 13从水合0.5分钟至3小时的梯牧草花粉中的释放动力学。通过免疫金场发射扫描和透射电子显微镜，将Phl p 13定位在干燥和水合的禾本科花粉粒中。
在代表禾本科主要亚科的所有12个野生和栽培禾本科属中均检测到第13组过敏原。在超微结构上，该过敏原位于梯牧草花粉粒的壁和细胞质中。在细胞质中，Phl p 13与多糖颗粒以及尚未描述的微管样结构堆叠相关。在雨水中水合后，花粉粒排出含有Phl p 13的可吸入大小的细胞质颗粒，在0.5分钟后即可在水性上清液中检测到。
第13组过敏原代表一组特异性存在于主要禾本科亚科花粉中的标记过敏原，花粉水合后与可吸入颗粒一起迅速释放。它们可被视为禾本科花粉暴露的环境标志物，而第13组特异性IgE抗体可作为真正的禾本科花粉致敏的免疫标志物。
