Like Aerosol Inhalation Exposure for Cytotoxicity Assessment Using Platforms

Lung exposure to inhaled particulate matter (PM) is known to injure the airway epithelium via inflammation, a phenomenon linked to increased levels of global morbidity and mortality. To evaluate physiological outcomes following PM exposure and concurrently circumvent the use of animal experiments, approaches have typically relied on traditional assays with plates or well inserts. Yet, these manifest drawbacks including the inability to capture physiological inhalation conditions and aerosol deposition characteristics relative to human conditions. Here, we present a novel exposure platform that emulates the epithelium of human bronchial airways with critical cellular barrier functions at an air-liquid interface (ALI). As a proof-of-concept for lung cytotoxicity testing, we recapitulate a well-characterized cell apoptosis pathway, induced through exposure to 2 μm airborne particles coated with αVR1 antibody that leads to significant loss in cell viability across the recapitulated airway epithelium. Notably, our inhalation assays enable simultaneous aerosol exposure across multiple airway chips integrated within a larger bronchial airway tree model, under physiological respiratory airflow conditions. Our findings underscore like aerosol deposition outcomes where patterns depend on respiratory flows across the airway tree geometry and gravitational orientation, as corroborated by concurrent numerical simulations. Our not only highlight the prospect of realistic exposure assays in recapitulating characteristic local deposition outcomes, such platforms open opportunities toward advanced exposure assays for preclinical cytotoxicity and drug screening applications.