Department of Chemical and Biological Engineering, Chalmers University of Technology, Kemivägen 10, Gothenburg, Sweden.
BMC Pulm Med. 2014 Jul 4;14:110. doi: 10.1186/1471-2466-14-110.
Improvements in asthma diagnosis and management require deeper understanding of the heterogeneity of the complex airway inflammation. We hypothesise that differences in the two major inflammatory phenotypes of asthma; eosinophilic and neutrophilic asthma, will be reflected in the lung protein expression profile of murine asthma models and can be delineated using proteomics of bronchoalveolar lavage (BAL).
BAL from mice challenged with ovalbumin (OVA/OVA) alone (standard model of asthma, here considered eosinophilic) or OVA in combination with endotoxin (OVA/LPS, model of neutrophilic asthma) was analysed using liquid chromatography coupled to high resolution mass spectrometry, and compared with steroid-treated animals and healthy controls. In addition, conventional inflammatory markers were analysed using multiplexed ELISA (Bio-Plex™ assay). Multivariate statistics was performed on integrative proteomic fingerprints using principal component analysis. Proteomic data were complemented with lung mechanics and BAL cell counts.
Several of the analysed proteins displayed significant differences between the controls and either or both of the two models reflecting eosinophilic and neutrophilic asthma. Most of the proteins found with mass spectrometry analysis displayed a considerable increase in neutrophilic asthma compared with the other groups. Conversely, the larger number of the inflammatory markers analysed with Bio-Plex™ analysis were found to be increased in the eosinophilic model. In addition, major inflammation markers were correlated to peripheral airway closure, while commonly used asthma biomarkers only reflect central inflammation.
Our data suggest that the commercial markers we are currently relying on to diagnose asthma subtypes are not giving us comprehensive or specific enough information. The analysed protein profiles allowed to discriminate the two models and may add useful information for characterization of different asthma phenotypes.
哮喘诊断和管理的改进需要更深入地了解复杂气道炎症的异质性。我们假设哮喘的两种主要炎症表型；嗜酸性粒细胞性和中性粒细胞性哮喘，将反映在哮喘小鼠模型的肺蛋白表达谱中，并可以通过支气管肺泡灌洗（BAL）的蛋白质组学来描绘。
用卵清蛋白（OVA/OVA）单独（哮喘的标准模型，在此被认为是嗜酸性粒细胞性）或 OVA 与内毒素（OVA/LPS，中性粒细胞性哮喘模型）联合攻击的小鼠的 BAL 进行分析，使用液相色谱法与高分辨率质谱法结合，并与接受类固醇治疗的动物和健康对照进行比较。此外，还使用多重 ELISA（Bio-Plex 测定法）分析了常规炎症标志物。使用主成分分析对整合蛋白质组指纹进行了多变量统计分析。蛋白质组数据补充了肺力学和 BAL 细胞计数。
几种分析的蛋白质在对照与两种模型之间的任何一种或两种模型之间显示出显著差异，反映了嗜酸性粒细胞性和中性粒细胞性哮喘。与其他组相比，通过质谱分析发现的大多数蛋白质在中性粒细胞性哮喘中显示出相当大的增加。相反，用 Bio-Plex 分析分析的较大数量的炎症标志物在嗜酸性粒细胞性模型中被发现增加。此外，主要炎症标志物与外周气道闭合相关，而常用的哮喘生物标志物仅反映中央炎症。
我们的数据表明，我们目前依赖于诊断哮喘亚型的商业标志物并没有为我们提供全面或足够具体的信息。分析的蛋白质谱允许区分两种模型，并可能为不同的哮喘表型特征提供有用的信息。
