Portelli Michael A, Ketelaar Maria E, Bates Stewart, Csomor Eszter, Shaw Dominick, Emsley Jonas, Brightling Christopher, Hall Ian, Affleck Karen, Edwards Matthew, Nawijn Martijn C, Koppelman Gerard H, Van Oosterhout Antoon J, Sayers Ian
Centre for Respiratory Research, National Institute for Health Research Nottingham Biomedical Research Centre, School of Medicine, Biodiscovery Institute, University of Nottingham, Nottingham, UK.
Groningen Research Institute for Asthma and COPD, Department of Pediatric Pulmonology and Pediatric Allergology, Beatrix Children's Hospital, University of Groningen, University Medical Center Groningen, Groningen, The Netherlands.
Clin Exp Allergy. 2024 Dec;54(12):984-995. doi: 10.1111/cea.14562. Epub 2024 Sep 20.
The interleukin-33/interleukin-1 receptor-like-1 (IL-33/IL1RL1) signalling pathway is implicated in asthma pathogenesis, with IL1RL1 nonsynonymous genetic polymorphisms associated with disease risk. We aimed to determine these variants' effect on IL1RL1 signalling induced by different IL33 isoforms thought to be elevated in the asthmatic airway.
In a project funded by GSK plc, which has developed an IL-33 receptor inhibitor for asthma treatment, human embryonic kidney 293 (HEK293) cells expressing secreted embryonic alkaline phosphatase (SEAP) driven by a nuclear factor kappa-beta (NF-κB) promoter, were transiently transfected with IL1RL1, containing one of four extracellular and Toll/interleukin 1 receptor (TIR) domain haplotypes. Cells were stimulated with seven different splice and proteolytic-generated IL-33 isoforms (0.001-50 ng/mL) for 24 h. Supernatant SEAP activity and interleukin-8 (IL-8) levels were determined. Primary human bronchial epithelial cells (HBECs) representing different genotype carriers were stimulated with IL-33 (50 ng/mL) and induced IL-8 mRNA expression measured.
HEK293 cells carrying both asthma extracellular and TIR domain IL1RL1 risk haplotypes presented maximal IL33-driven signalling, with minimal signalling after IL-33 activation in other protective haplotypes. All IL-33 isoforms activated IL1RL1 but with differing magnitudes. Proteolytically cleaved IL33 and IL33 had the greatest effect and the IL33, and Exon 3,4 deletion isoform exhibited the lowest. The effect of extracellular and TIR domain genetic variants on receptor signalling was replicated in primary HBECs. Maximal IL1RL1 signalling was observed in cells carrying both extracellular and TIR signalling domain risk haplotypes.
Overall, our study suggests asthma patients carrying the extracellular and TIR domain risk haplotype and have a lung microenvironment that promotes elevated levels of cleaved IL33, particularly where IL33 and IL33 may be more amenable to IL33/IL1RL1 targeting.
白细胞介素-33/白细胞介素-1受体样1（IL-33/IL1RL1）信号通路与哮喘发病机制有关，IL1RL1非同义基因多态性与疾病风险相关。我们旨在确定这些变异对不同IL33亚型诱导的IL1RL1信号传导的影响，这些亚型在哮喘气道中被认为会升高。
在葛兰素史克公司资助的一个项目中（该公司已开发出一种用于哮喘治疗的IL-33受体抑制剂），将由核因子κB（NF-κB）启动子驱动表达分泌型胚胎碱性磷酸酶（SEAP）的人胚肾293（HEK293）细胞，用包含四种细胞外和Toll/白细胞介素1受体（TIR）结构域单倍型之一的IL1RL1进行瞬时转染。用七种不同的剪接和蛋白水解产生的IL-33亚型（0.001 - 50 ng/mL）刺激细胞24小时。测定上清液中的SEAP活性和白细胞介素-8（IL-8）水平。用IL-33（50 ng/mL）刺激代表不同基因型携带者的原代人支气管上皮细胞（HBECs），并测定诱导的IL-8 mRNA表达。
携带哮喘细胞外和TIR结构域IL1RL1风险单倍型的HEK293细胞呈现出最大的IL33驱动信号，而在其他保护性单倍型中，IL-33激活后的信号最小。所有IL-33亚型均激活IL1RL1，但程度不同。蛋白水解切割的IL33和IL33的作用最大，而IL33和外显子3、4缺失亚型的作用最低。细胞外和TIR结构域基因变异对受体信号传导的影响在原代HBECs中得到了验证。在同时携带细胞外和TIR信号结构域风险单倍型的细胞中观察到最大的IL1RL1信号。
总体而言，我们的研究表明，携带细胞外和TIR结构域风险单倍型的哮喘患者具有促进切割型IL33水平升高的肺微环境，特别是在IL33和IL33可能更适合进行IL33/IL1RL1靶向治疗的情况下。
