Figure 6.

Other classes of potentiators have widely varying effects on CFTR2 mutant expression. (A) PM densities of CFTR2 mutants expressed in CFBE cells after 24 h treatment with potentiators from the CFFT panel that downregulate F508del expression (22), with and without VX-809 (3 μM). Potentiators were used at the following concentrations: P2, P3—3 µM; P8—20 µM; P1, P4, P7–30 µM, P6–100 µM. The PM densities were normalized for cell viability and are expressed as % of DMSO control (dotted line). (B) Cell surface expression of CFBE cells expressing a subset of CFTR2 mutants performed after 24 h incubation with P5, P10, P12, A04 or H02 (10 μM), five potentiators that do not downregulate F508del-CFTR (42). The dotted line represents the expression in DMSO treated cells. (C) Immunoblots of CFBE cells expressing the indicated CFTR mutants after incubation for 24 h with P12, A04 or H02 (10 μM), with and without VX-809 (3 μM). CFTR was detected with anti-HA antibody, Na⁺/K⁺ ATPase served as loading control. The empty arrowheads show the mature, complex glycosylated CFTR protein (C-band), and the filled arrowhead show the immature, core glycosylated protein (B-band). All experiments are n = 3; error bars are SEM.