A perfusable decellularized plant-based air-liquid-interface-on-a-chip for investigating inorganic dust aerosol exposure

Dust exposure affects an estimated 330 million people worldwide and can penetrate deep into the respiratory tract, disrupting epithelial and endothelial barriers. However, current in vitro models do not recapitulate the perfusable airway-vascular interface required to investigate dust-induced barrier alterations. Bioinspired scaffolds from decellularized plants hold strong potential as new approach methodologies (NAMs), considering the need for physiologically relevant in vitro models with vascular networks. Herein, we developed a decellularized plant-based air-liquid interface (ALI)-on-a-chip to study inorganic dust aerosol exposure in human airway epithelial barrier. The decellularization method achieved ≥ 99% DNA removal and a hydrophilic interface, while preserving vascular network and cellulose-rich extracellular matrix. Subsequently, human umbilical vein endothelial cells and bronchial epithelial cells were seeded to the decellularized scaffold, positioned on a PDMS-based platform to reconstruct a perfusable ALI-on-a-chip. Nanoscale dust particles were administered to the epithelium. The dust particles resulted in a significant decrease in barrier integrity, where the TEER value of the epithelial barrier decreased from ~ 126.42 to ~ 56.11Ω*cm², with altered cell viabilities, and significant increases in pro-inflammatory cytokines such as TNF-α and IL-6. Our study reports the effects of inhaled dust aerosols on pulmonary barriers, along with offering a plant-based, biocompatible, and tissue-emulating air-liquid interface on-a-chip model. The developed model offers a versatile platform for studying toxicity of diverse particles and a preclinical evaluation of respiratory therapeutics.