Airways Disease, National Heart & Lung Institute, Imperial College London, and the Biomedical Research Unit, Royal Brompton & Harefield NHS Trust, London, United Kingdom.
Department of Computing & Data Science Institute, Imperial College London, London, United Kingdom; Janssen Research and Development, High Wycombe, United Kingdom.
J Allergy Clin Immunol. 2018 Feb;141(2):560-570. doi: 10.1016/j.jaci.2017.02.045. Epub 2017 May 18.
Sputum analysis in asthmatic patients is used to define airway inflammatory processes and might guide therapy.
We sought to determine differential gene and protein expression in sputum samples from patients with severe asthma (SA) compared with nonsmoking patients with mild/moderate asthma.
Induced sputum was obtained from nonsmoking patients with SA, smokers/ex-smokers with severe asthma, nonsmoking patients with mild/moderate asthma (MMAs), and healthy nonsmoking control subjects. Differential cell counts, microarray analysis of cell pellets, and SOMAscan analysis of sputum analytes were performed. CRID3 was used to inhibit the inflammasome in a mouse model of SA.
Eosinophilic and mixed neutrophilic/eosinophilic inflammation were more prevalent in patients with SA compared with MMAs. Forty-two genes probes were upregulated (>2-fold) in nonsmoking patients with severe asthma compared with MMAs, including IL-1 receptor (IL-1R) family and nucleotide-binding oligomerization domain, leucine-rich repeat and pyrin domain containing 3 (NRLP3) inflammasome members (false discovery rate < 0.05). The inflammasome proteins nucleotide-binding oligomerization domain, leucine rich repeat and pyrin domain containing 1 (NLRP1), NLRP3, and nucleotide-binding oligomerization domain (NOD)-like receptor C4 (NLRC4) were associated with neutrophilic asthma and with sputum IL-1β protein levels, whereas eosinophilic asthma was associated with an IL-13-induced T2 signature and IL-1 receptor-like 1 (IL1RL1) mRNA expression. These differences were sputum specific because no activation of NLRP3 or enrichment of IL-1R family genes in bronchial brushings or biopsy specimens in patients with SA was observed. Expression of NLRP3 and of the IL-1R family genes was validated in the Airway Disease Endotyping for Personalized Therapeutics cohort. Inflammasome inhibition using CRID3 prevented airway hyperresponsiveness and airway inflammation (both neutrophilia and eosinophilia) in a mouse model of severe allergic asthma.
IL1RL1 gene expression is associated with eosinophilic SA, whereas NLRP3 inflammasome expression is highest in patients with neutrophilic SA. T2-driven eosinophilic inflammation and neutrophil-associated inflammasome activation might represent interacting pathways in patients with SA.
对哮喘患者的痰分析用于定义气道炎症过程，并可能指导治疗。
我们旨在确定与非吸烟的轻度/中度哮喘患者相比，严重哮喘（SA）患者的痰样本中的差异基因和蛋白表达。
从非吸烟的 SA 患者、吸烟/戒烟的严重哮喘患者、非吸烟的轻度/中度哮喘患者（MMAs）和健康的非吸烟对照中获得诱导痰。进行差异细胞计数、细胞沉淀的微阵列分析和痰分析物的 SOMAscan 分析。使用 CRID3 抑制 SA 小鼠模型中的炎症小体。
与 MMAs 相比，SA 患者中嗜酸性粒细胞和混合嗜中性粒细胞/嗜酸性粒细胞炎症更为常见。与 MMAs 相比，42 个基因探针在非吸烟的严重哮喘患者中上调（>2 倍），包括白细胞介素-1 受体（IL-1R）家族和核苷酸结合寡聚化结构域，富含亮氨酸重复和吡喃结构域包含 3（NLRP3）炎症小体成员（假发现率<0.05）。炎症小体蛋白核苷酸结合寡聚化结构域，富含亮氨酸重复和吡喃结构域包含 1（NLRP1）、NLRP3 和核苷酸结合寡聚化结构域（NOD）样受体 C4（NLRC4）与嗜中性哮喘和痰中 IL-1β 蛋白水平相关，而嗜酸性哮喘与 IL-13 诱导的 T2 特征和白细胞介素-1 受体样 1（IL1RL1）mRNA 表达相关。这些差异是痰特异性的，因为在 SA 患者的支气管刷检或活检标本中没有观察到 NLRP3 的激活或 IL-1R 家族基因的富集。在气道疾病个体化治疗的表型分型队列中验证了 NLRP3 和 IL-1R 家族基因的表达。使用 CRID3 抑制炎症小体可预防严重过敏性哮喘小鼠模型中的气道高反应性和气道炎症（中性粒细胞增多和嗜酸性粒细胞增多）。
IL1RL1 基因表达与嗜酸性 SA 相关，而 NLRP3 炎症小体表达在嗜中性粒细胞 SA 患者中最高。T2 驱动的嗜酸性炎症和中性粒细胞相关炎症小体激活可能代表 SA 患者中相互作用的途径。
