Inflammation-induced loss of CFTR-expressing airway ionocytes in non-eosinophilic asthma

Ling Chen; Gabriela A Hoefel; Prabuddha S Pathinayake; Andrew Reid; Amber L Pillar; Coady Kelly; HuiYing Tan; Ayesha Ali; Richard Y Kim; Philip M Hansbro; Steven L Brody; Paul S Foster; Jay C Horvat; Carlos Riveros; Nikhil Awatade; Peter A B Wark; Gerard E Kaiko

doi:10.1111/resp.14833

Inflammation-induced loss of CFTR-expressing airway ionocytes in non-eosinophilic asthma

Respirology. 2024 Oct 2. doi: 10.1111/resp.14833. Online ahead of print.

Authors

Ling Chen^{1

2}, Gabriela A Hoefel^{1

2}, Prabuddha S Pathinayake^{2

3}, Andrew Reid^{2

3}, Amber L Pillar^{1

2}, Coady Kelly^{1

2}, HuiYing Tan^{1

2}, Ayesha Ali^{1

2}, Richard Y Kim^{1

2

4}, Philip M Hansbro^{1

5}, Steven L Brody⁶, Paul S Foster^{1

2}, Jay C Horvat^{1

2}, Carlos Riveros², Nikhil Awatade^{2

3}, Peter A B Wark^{2

3

7

8}, Gerard E Kaiko^{1

2}

Affiliations

¹ School of Biomedical Sciences and Pharmacy, University of Newcastle, Newcastle, New South Wales, Australia.
² Immune Health Program, Hunter Medical Research Institute, New Lambton Heights, New South Wales, Australia.
³ School of Medicine and Public Health, University of Newcastle, Newcastle, New South Wales, Australia.
⁴ School of Life Sciences, University of Technology Sydney, Sydney, New South Wales, Australia.
⁵ Centre for Inflammation, Centenary Institute and University of Technology Sydney, Faculty of Science, School of Life Sciences, Sydney, New South Wales, Australia.
⁶ Department of Medicine, Washington University School of Medicine in St Louis, St Louis, Missouri, USA.
⁷ Department of Respiratory and Sleep Medicine, John Hunter Hospital, New Lambton, New South Wales, Australia.
⁸ Department of Respiratory Medicine, Alfred Health, Melbourne, Victoria, Australia.

PMID: 39358991
DOI: 10.1111/resp.14833

Abstract

Background and objective: Severe asthma is a heterogeneous disease with subtype classification according to dominant airway infiltrates, including eosinophilic (Type 2 high), or non-eosinophilic asthma. Non-eosinophilic asthma is further divided into paucigranulocytic or neutrophilic asthma characterized by elevated neutrophils, and mixed Type 1 and Type 17 cytokines in the airways. Severe non-eosinophilic asthma has few effective treatments and many patients do not qualify for biologic therapies. The cystic fibrosis transmembrane conductance regulator (CFTR) is dysregulated in multiple respiratory diseases including cystic fibrosis and chronic obstructive pulmonary disease and has proven a valuable therapeutic target. We hypothesized that the CFTR may also play a role in non-eosinophilic asthma.

Methods: Patient-derived human bronchial epithelial cells (hBECs) were isolated and differentiated at the air-liquid interface. Single cell RNA-sequencing (scRNAseq) was used to identify epithelial cell subtypes and transcriptional activity. Ion transport was investigated with Ussing chambers and immunofluorescent quantification of ionocyte abundance in human airway epithelial cells and murine models of asthma.

Results: We identified that hBECs from patients with non-eosinophilic asthma had reduced CFTR function, and did not differentiate into CFTR-expressing ionocytes compared to those from eosinophilic asthma or healthy donors. Similarly, ionocytes were also diminished in the airways of a murine model of neutrophilic-dominant but not eosinophilic asthma. Treatment of hBECs from healthy donors with a neutrophilic asthma-like inflammatory cytokine mixture led to a reduction in ionocytes.

Conclusion: Inflammation-induced loss of CFTR-expressing ionocytes in airway cells from non-eosinophilic asthma may represent a key feature of disease pathogenesis and a novel drug target.

Keywords: CFTR; airway epithelium; ionocytes; mucous; neutrophils; severe asthma; single cell RNA‐sequencing.

Abstract

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