Novel in-vitro model to study first responses of airway epithelial cells to allergen and pro-inflammatory stimuli at birth

Abstract

BackgroundThe airway epithelium is increasingly being implicated in the pathogenesis of asthma. Although believed to be important, little is known about how the neonatal airway epithelial cell (AEC) phenotype impacts on respiratory disease in later life. The aim of this study was to establish a methodology for culturing neonatal nasal AEC and to describe AEC response in vitro. MethodsAECs were sampled from healthy, unsedated infants during the first week of life by brushing both nostrils with an interdental brush. Sampled AECs were used for cytospin preparation or grown to confluence before subculture. Cultured cells were characterised morphologically and by immunocytochemistry. Interleukin-8 concentrations were measured in supernatants from monolayers at rest and after exposure to concentration ranges of interleukin 1β and tumour necrosis factor α or house dust mite extract. FindingsPrimary cultures were successfully established in 109 (92%) of 117 neonates sampled, with 93 (80%) successfully cultured to confluence at third passage. The epithelial lineage of the cells was confirmed by morphological analysis and immunocytochemistry. Constitutive interleukin-8 secretion was observed and was upregulated by both stimuli in a dose dependent manner. InterpretationWe describe a safe, minimally invasive method of culturing AECs from neonates suitable for functional cell analysis and amenable to large population based studies. This novel technique offers a unique opportunity to study naive AECs not yet exposed to the modifying effects of environmental pollutants and viral pathogens and may prove useful in elucidating the early origins of asthma. FundingChief Scientist Office of the Scottish Government.