Deleterious impact ofPseudomonas aeruginosaon cystic fibrosis transmembrane conductance regulator function and rescue in airway epithelial cells

Abstract

The epithelial response to bacterial airway infection, a common feature of lung diseases such as chronic obstructive pulmonary disease and cystic fibrosis, has been extensively studied. However, its impact on cystic fibrosis transmembrane conductance regulator (CFTR) channel function is not clearly defined. Our aims were, therefore, to evaluate the effect of Pseudomonas aeruginosa on CFTR function and expression in non-cystic fibrosis airway epithelial cells, and to investigate its impact on ΔF508-CFTR rescue by the VRT-325 corrector in cystic fibrosis cells.CFTR expression/maturation was evaluated by immunoblotting and its function by short-circuit current measurements.A 24-h exposure to P. aeruginosa diffusible material (PsaDM) reduced CFTR currents as well as total and membrane protein expression of the wildtype (wt) CFTR protein in CFBE-wt cells. In CFBE-ΔF508 cells, PsaDM severely reduced CFTR maturation and current rescue induced by VRT-325. We also confirmed a deleterious impact of PsaDM on wt-CFTR currents in non-cystic fibrosis primary airway cells as well as on the rescue of ΔF508-CFTR function induced by VRT-325 in primary cystic fibrosis cells.These findings show that CFTR function could be impaired in non-cystic fibrosis patients infected by P. aeruginosa. Our data also suggest that CFTR corrector efficiency may be affected by infectious components, which should be taken into account in screening assays of correctors. @ERSpublications Exposure of airway epithelial cell to P. aeruginosa impairs CFTR function, expression and rescue by correctors http://ow.ly/IleTw

Quorum‐sensing inhibition abrogates the deleterious impact of Pseudomonas aeruginosa on airway epithelial repair

“…Non‐CF primary hAECs were isolated from nasal tissues that were obtained from patients without lung pathology who underwent nasal surgery at Centre Hospitalier de l'Universitéal (CHUM; Montréde Montréal, QC, Canada). CF hAECs were collected from patients with CF after nasal surgery at CHUM and Sainte‐Justine hospitals (Montréal, QC, Canada), and bronchial tissues were collected from patients with CF who underwent lung transplantation (25, 29, 30), according to approved ethical protocols (Comitéd'éthique de la recherche du CHUM; CE 08.063 and HD 04.025) and with patients providing written informed consent. After recovery, tissues were rinsed and incubated for 18 h at 4°C with MEM (Thermo Fisher Scientific Life Sciences, Waltham, MA, USA) that was supplemented with 7.5% NaHCO 3 (Sigma‐Aldrich, St. Louis, MO, USA), 2 mM L‐glutamine (Thermo Fisher Scientific Life Sciences), 10 mM HEPES (Thermo Fisher Scientific Life Sciences), 0.05 mg/ml gentamycin (Sandoz, Boucherville, QC, Canada), 100 U/ml penicillin‐streptomycin, 0.25 mg/ml fungizone (Thermo Fisher Scientific Life Sciences), 0.1% protease (Sigma‐Aldrich), and 10 mg/ml DNAse (Sigma‐Aldrich).…”

Anti-Infectives Restore ORKAMBI® Rescue of F508del-CFTR Function in Human Bronchial Epithelial Cells Infected with Clinical Strains of P. aeruginosa

“…This broad loss in CFTR function, even in ORKAMBI ® -rescued F508del-CFTR cells, implies that a similar response to bacteria is responsible for the loss in CFTR function. It has previously been shown that expression of mature CFTR to the apical membrane decreases upon infection with P. aeruginosa bacteria [16][17][18], even in cells that were pre-treated with CFTR correctors (VX-809 or VRT-325) [17,18]. Further, Bomberger et al, have shown that outer membrane vesicles secreted from P. aeruginosa increase the degradation of apical CFTR by redirecting recycled CFTR from endosomes to lysosomes [38,39].…”

“…Low efficacy and high patient-to-patient variation in ORKAMBI ® response might feasibly be attributed, in part, to differences in types of microbial infections across patients and even within a single patient over time [14,15]. P. aeruginosa (lab strain PAO1) exposure has been shown to reduce corrector-mediated rescue (VX-809 or VRT-325) of CFTR in human bronchial epithelial cells (HBE) [16][17][18] and stimulate the expression of the pro-inflammatory cytokines, IL-6 and IL-8 [18,19]. On the other hand, 4,6,4 -trimethylangelicin (TMA), which is a dual-acting compound (CFTR corrector and potentiator), has been shown to exert its action by interacting directly with the CFTR protein, and reducing P. aeruginosa-dependent IL-8 secretion [20][21][22][23][24].…”

Global reprogramming of virulence and antibiotic resistance inPseudomonas aeruginosaby a single nucleotide polymorphism in the elongation factor-encoding gene,fusA1

“…In CF, defective mucociliary clearance causes an accumulation of a thick mucus plugs within the airways. Such oxygen-limited environments provide the perfect niche for P. aeruginosa to thrive (Ratjen et al, 2003;Trinh et al, 2015).…”