Journal: npj Drug Discovery
Article Title: Triple potentiator combinations increase the functional correction of several CFTR gating mutants
doi: 10.1038/s44386-026-00061-6
Figure Lengend Snippet: A Representative traces (left) of the I sc of G551D-CFTR in gene-edited (ge) 16HBE cells activated with forskolin (Fsk, 20 μM) and potentiated with VX-770 (3 μM) followed by VX-445 (2 μM) and apigenin (50 µM) or in reverse order. At the end of the experiment, CFTR was inhibited with CFTR Inh -172 (20 μM). Measurements were performed in the presence of a basolateral-to-apical chloride gradient in the presence of 100 μM amiloride. Quantification of the I sc (right, n = 3) shows the contribution of Fsk, VX-770, VX-445, and apigenin to the maximal current, depending on the order of potentiator addition, expressed as a percentage of the forskolin-stimulated WT-CFTR current in 16HBE14o- cells. N.s. – not significant, * P < 0.05, ** P < 0.01, *** P < 0.001 by unpaired two-tailed t-test for the successive addition of potentiators. B Immunoblot (top panel) of parental 16HBE14o- or 16HBEge expressing endogenous WT- or G551D-CFTR, respectively. CFTR was visualized with 660 antibody, and anti–Na + /K + -ATPase antibody served as a loading control. The empty arrowheads indicate the mature, complex glycosylated CFTR (C-band), the filled arrowheads show the immature, core glycosylated protein (B-band). The relative abundance of the C-band was quantified by densitometry (lower panel, n = 4). C Representative traces (left) and quantification of the I sc (right) in HNE isolated from one patient homozygous for G551D-CFTR upon activation with forskolin (Fsk, 20 μM) and potentiation with VX-770 (3 μM), VX-445 (2 μM) and apigenin (50 μM) expressed as percentage of mean Fsk-induced WT-CFTR currents in HNE from 10 healthy donors. Measurements were performed as in panel A. N.s. – not significant, * P < 0.05, ** P < 0.01, *** P < 0.001 by unpaired two-tailed t-test for the successive addition of potentiators. D Inside-out patch clamp recording of G551D-CFTR in the presence of 2 mM ATP + 300 nM PKA (black), +50 nM Vx-770 (green), +1 µM VX-445 (blue), +1 µM apigenin (blue), and +50 µM P-dATP (orange, ’CCC’ (channel counting cocktail)). Membrane potential was -80 mV, scales of time and amplitude are shown, gray section illustrates channel closure upon simultaneous removal of ATP, PKA and compounds. E Calculated absolute values of P o for the four segments ( n = 7-8) obtained as described in Methods. * P < 0.05, ** P < 0.01 by one-way ANOVA followed by Tukey’s post-hoc test. F ) Effect of VX-770 (3 μM) or apigenin (50 μM) on the potency of VX-445 for the phosphorylated G551D-CFTR potentiation, measured by halide-sensitive YFP quenching assay in CFBE41o- cells ( n = 3). Values are expressed as a percentage of the response to 3 μM VX-770. G Effect of VX-770 (3 μM) or VX-445 (2 μM) on the potency of apigenin for the phosphorylated G551D-CFTR potentiation, determined by the YFP quenching assay in CFBE41o- cells ( n = 3). Data in ( A , B , E – G ) are means ± SEM of the indicated number of independent experiments. Data in ( C ) are means ± SD of three measurements.
Article Snippet: CFTR modulators VX-445, VX-770 and ABBV-974 (former GLPG1837), as well as forskolin and CFTR Inh -172, were purchased from MedChemExpress.
Techniques: Two Tailed Test, Western Blot, Expressing, Control, Isolation, Activation Assay, Patch Clamp, Membrane