106 Establishing a Physiologically Relevant in Vitro Airway Model to Assess the Impacts of Environmental Exposures, Like Smoking, on Covid-19 Susceptibility.

Abstract Air-liquid interface (ALI) cultures are commonly used for 3D modelling of the human airways and to examine effects direct exposure airborne toxicants. We explored suitability epithelial cell lines (RPMI 2560, HBEC-3KT, CALU-3 A549) primary cells (nasal, bronchiolar small airways) grown at ALI as a physiologically relevant model whether environmental exposures can increase susceptibility SARS-COV-2 infection. Cultures were kept up 28 days allow differentiation. Trans-epithelial electrical resistance (TEER) was measured weekly. Cells harvested 0, 7, 14, 21 days, transcriptional markers basal, ciliated mucus-producing together with viral entry genes (ACE2, TMPRSS2 Furin) other interest, assessed by reverse-transcription quantitative PCR. Each line yielded differentiated models, upregulation mucus producing from day 7. In contrast cells, immortalised did not produce cilia but, produced. TEER values increased time, expected, but therefore formation tight junctions differed between models. Similarly, expression marked differences across different This study will be select most appropriate investigating effect such smoking vaping on