Extended Data Figure 3 |. AmB treatment is sustained, ineffective on wild type, not due to increased CFTR activity, does not disturb membrane integrity, and is non-toxic.

The effect of AmB (2 μM) or FC-72 vehicle left on the surface of CuFi-1 (ΔF508/ΔF508) epithelia for (a) 7 (n = 6 biologically independent samples, p = 0.0004), (b) 14 (n = 9 biologically independent samples, p = 0.5138), or (c) 28 days (n = 6 biologically independent samples, p = 0.3421) on H14CO₃⁻ movement from the basolateral buffer to the ASL over 10 minutes post-radiolabel addition, as normalized to FC-72 vehicle addition. Changes in transepithelial current (It) after treatment with 10 μM forskolin/100 μM IBMX (FI) to activate CFTR and 1 μM CFTRinh-172 to inhibit CFTR in (d,g) NuLi (CFTR^+/+) epithelia, (e,h) CuFi-1 (ΔF508/ΔF508) epithelia, and (f,i) CuFi-1 epithelia treated with AmB (2 μM; 48 hours) (n = 6 biologically independent samples). In (g) to (i), a representative graph from 6 independent experiments repeated with similar results is shown. (j) Transepithelial electrical resistance (Rt) in CuFi-1 epithelia did not differ between treatment with vehicle or increasing doses of AmB over increasing time periods after a single treatment (n = 9 biologically independent samples). (k) Cytotoxicity as measured by detection of lactase dehydrogenase in CuFi-1 epithelia over increasing time periods after a single AmB or vehicle treatment, represented as percent of total cellular lysis by Triton X-100. AmB treatment did not cause increased cytotoxicity as compared to vehicle (n = 12 biologically independent samples). In (a) to (c), two-sided unpaired Student’s t test was used to assess statistical significance. In (a) to (f) and (j) to (k), graphs depict means ± SEM; NS, not significant; ***P ≤ 0.001 relative to vehicle control. In all panels, measurements were taken from biologically independent samples.