3D air-liquid interface culture of Cystic Fibrosis bronchial epithelia, macrophages and P. aeruginosa to assess host-pathogen interaction and drug efficacy

Abstract

To establish a predictive human infected in vitro system for Cystic fibrosis (CF) lung infection, we set-up a P. aeruginosa-infected model at the air-liquid interface (ALI), constituted by the human cystic fibrosis bronchial epithelial cells (CFBE41o-) in the apical side of a transwell and human macrophages (THP-1) in the basolateral side. Planktonic P. aeruginosa infection of CFBE41o- cells led to an earlier biofilm formation after 6 hours. Macrophages migrated towards the infection side, on the apical compartment already after 3 hours of infection, and were able to internalize the bacteria. Upon tobramycin treatment, the bacterial killing was higher on an abiotic surface (plastic plates) than on cell surface, which suggests an overestimation of the drug efficacy in cell-free assays. Perspectively, this model can be used to further investigate the immune system. Here, we present the characterization of a neutrophil-like cell, HL-60, and its potential to be a platform to use neutrophils as delivery methods of internalized nanoparticle therapy. Aiming for therapy, we assessed the potential of quaternary ammonium surfactant-liposomes to inhibit bacterial adherence. That was the first step to develop a particle to simultaneously inhibit adhesion and provide encapsulation of antibiotic drugs as combination drug delivery.