FIGURE 1.

Azithromycin (AZ) has no synergistic/antagonist effect on ion channels upon combination with elexacaftor/tezacaftor/ivacaftor (ETI) in homozygous (F508del/F508del) cystic fibrosis (CF) human bronchial epithelial (HBE) cells at 24 h. a) Representative traces of equivalent current (I_eq) over time. CF HBE primary cells grown at the air–liquid interface were pre-treated basolaterally for 24 h with vehicle control (VC) dimethylsulfoxide (0.08%; v/v), AZ (10 µg·mL⁻¹), ETI (elexacaftor/tezacaftor/lumacaftor; 3/18/1 µM) and ETI+AZ in combination. Changes in I_eq were measured using the Multi Trans-Epithelial Current Clamp-24 system after the apical addition of amiloride (10 µM), forskolin (20 µM), CFTR_inh172 (20 µM) and uridine-5′-triphosphate (UTP) (100 µM). Quantified b) amiloride-sensitive I_eq; c) forskolin-induced I_eq; d) CFTR_inh172-sensitive I_eq and e) UTP-induced I_eq (µA·cm⁻²) are shown. Amil: amiloride; FSK: forskolin; I_eq: . Data are presented as mean±sem. Statistical analyses were performed using a Kruskal–Wallis statistical test with Dunn's multiple comparisons post hoc test. *: p-value≤0.05; **: p≤0.01; ***: p≤0.001. n=6 (three filters each from two donors).