Crosstalk between airway epithelial cells from healthy and wheezing children and leukocytes in respiratory syncytial virus infection

Abstract

Early childhood wheeze manifests in almost a third of young children and is often associated with the development of asthma later in life. Its ontogeny and pathology as well as the determinants that decide its resolution or progression to asthma throughout childhood remain uncertain. Building on previously established associations between early life viral infections and the development of wheeze and asthma, we sought to explore the mechanisms underlying asthma ontogeny. We hypothesized that differences in the airway epithelial cells from healthy and wheezing children induce differential responses in leukocytes when exposed to pathogens such as Respiratory Syncytial Virus (RSV).

To explore this hypothesis, we developed a co-culture model encompassing well-differentiated primary nasal airway epithelial cells (WD-PNECs) from healthy and wheezing children and peripheral blood mononuclear cells (PBMCs) from healthy adult donors. Following early optimization experiments we characterised the crosstalk between WD-PNECs and PBMCs during RSV infection. The activation of CD4- and CD8- and γδ T-cells, NK cells and monocytes following co-culture with mock- or RSV-infected WD-PNECs was determined based on their expression of the activation marker CD69. RSV growth kinetics in WD-PNECs, epithelial integrity and cytokine secretion from both WD-PNECs and PBMCs were also analysed to characterise the effects of co-culture. Gene expression patterns of prominent antiviral proteins (ISG15, IRF9, Mx1 and RSAD2) and junctional proteins (CLDN1, CLDN4, CDH1 and CTNNB1) were analysed to set the results obtained for virus growth and epithelial integrity during co-culture into perspective. Results obtained from healthy and wheezing WD-PNECs were contrasted to identify functional differences in the antiviral response of airway epithelial cells from healthy and wheezing children. 

 In summary, this work characterises a co-culture model of WD-PNECs and PBMCs and discusses its unique potential as a platform for further investigations of the crosstalk profiles that underpin lung pathologies such as RSV-infection and childhood wheeze. 

Thesis is embargoed until 31 July 2026.

Date of Award	Jul 2024
Original language	English
Awarding Institution	Queen's University Belfast
Sponsors	Northern Ireland Department for the Economy & Wellcome Trust Breathing Together consortium
Supervisor	Michael Shields (Supervisor) & Ultan Power (Supervisor)