Gene expression analysis of nasal mucosa in birch pollen allergic and non-allergic individuals upon nasal provocation with birch pollen

Birch pollen is a significant cause of allergic rhinitis, yet the mechanisms of sensitization is to be understood completely. Here, we investigate the changes in gene expression of birch pollen allergic and non-allergic individuals that occur as a result of nasal provocation with birch pollen. This study was conducted specifically outside the birch pollen season to ensure that the results obtained are due to the nasal provocation alone and not to the exposure to birch pollen in the environment. 11 birch pollen allergic and 12 birch pollen non-allergic individuals participated in the study. All participants made two visits where they were subjected to nasal provocation with saline solution at visit 1 (baseline) and birch pollen solution at visit 2. At visit 1, nasal scrapings were collected 15 minutes following nasal provocation. The participants were randomized into four groups according to the time point of sample collection (15, 30, 60 or 120 minutes) following nasal provocation at visit 2. Nasal scrapings were collected at the respective time points. Total RNA was isolated from the nasal scrapings, Sequencing libraries from total RNA were prepared at the Core Facility Genomics, Medical University of Vienna, using the QuantSeq FWD protocol (Lexogen) and the pooled libraries were sequenced on a NextSeq500 instrument (Illumina) in 1x75bp single-end sequencing mode.

桦树花粉是引发变应性鼻炎（allergic rhinitis）的重要诱因之一，但其致敏机制尚未完全阐明。本研究针对桦树花粉致敏者与非致敏者，探究其在接受桦树花粉鼻腔激发试验（nasal provocation）后发生的基因表达变化。本研究特意选择在非桦树花粉季开展，以确保所得结果仅源于鼻腔激发试验，而非受环境中桦树花粉暴露的影响。本研究共纳入11名桦树花粉致敏者与12名非致敏者。所有受试者均参与两次访视：第一次访视（基线期）接受生理盐水鼻腔激发，第二次访视则接受桦树花粉溶液鼻腔激发。在第一次访视中，受试者于鼻腔激发后15分钟采集鼻腔刮取物（nasal scrapings）。受试者根据第二次访视鼻腔激发后的样本采集时间点（15、30、60或120分钟）被随机分为四组，并于对应时间点采集鼻腔刮取物。从鼻腔刮取物中分离总RNA（total RNA）；随后由维也纳医科大学基因组学核心设施（Core Facility Genomics, Medical University of Vienna）采用Lexogen公司的QuantSeq FWD建库方案构建总RNA测序文库（sequencing libraries）；最后将混合文库置于Illumina NextSeq500测序仪上，以1x75bp单端测序（single-end sequencing）模式完成测序。