Rouabhia M, Piché M, Corriveau MN, et al. - Researchers conducted the study for analyzing the impact of e-cigarettes on nasal epithelial cell and tissue behaviours. Human primary nasal epithelial cells and engineered 3D nasal mucosa tissues have been exposed or not to either e-cigarette aerosol or standard cigarette smoke. Then cell viability and lactate dehydrogenase activity were evaluated. Tissues exposed to e-cigarette aerosol showed structural deregulation, with more large-sized cells, fewer Ki67-positive cells, and a lower rate of proliferation compared with non-exposed tissues. Cytokine measurements exhibited high levels of IL-6, IL-8, TNFα, and MCP-1, showing that e-cigarettes activated pro-inflammatory cytokine responses. E-cigarette aerosol had adverse effects on nasal epithelial cells and nasal engineered mucosa tissue. Such results suggest that e-cigarettes can be a danger to nasal tissues and can impair the innate immune function of nasal epithelial cells.