Figure 7
Primary HBE cells revealed that glafenine, compound 49 and MF63 are potent correctors of class 2 CFTR mutations. (A) FMP assay (FMP) that monitors membrane depolarization induced by forskolin + genistein when cells are pretreated for 24 h with glafenine, its derivative, compound 49 and MF63 (all at 10 μM) and separately with VX-809 (1 µM) and Trikafta, performed in Fischer rat thyroid (FRT) expressing a selection of class 2 CFTR mutations (F508del-, G85E, and N1303K), (n = 3). (B) G85E-CFTR functional expression in well-differentiated primary human bronchial epithelial (HBE) cells determined from the increase in short-circuit current stimulated by acute addition of forskolin + VX-770 (ΔIsc), (NB It should be noted that the cells of this patient were heterozygotic in which one allele expressed G85E-CFTR and the other expressed the class 1 type mutation 621-1GT-CFTR). Representative Isc responses of primary HBE cells expressing G85E-CFTR to sequential addition of 10 µM forskolin, 100 nM VX-770, and 10 µM CFTRinh-172 after 24 h preincubation with 0.1% dimethyl sulfoxide (vehicle), glafenine (10 µM) or VX-809 (1 μM), compound 49 (10 μM) and MF63 (10 μM), and Trikafta (N = 3). (C) Graphical representation of the Ussing chamber experiment outlined in (B). (D) Class 1 type 621-1GT-CFTR functional expression in well-differentiated primary human bronchial epithelial (HBE) cells determined from the increase in short-circuit current stimulated by acute addition of forskolin + genistein (ΔIsc). Representative Isc responses of primary HBE cells expressing 621-1GT-CFTR to sequential addition of 10 µM forskolin, 50 µM genistein, and 10 µM CFTRinh-172 after 24 h preincubation with 0.1% dimethylsulfoxide (vehicle), VX-809 (1 μM), glafenine, compound 49, and MF63 (all at 10 µM), (n = 3). Data in A and D are presented as the means ± SEM, n = 4, *p < 0.05, **p < 0.01 and ***p < 0.001.
