CFTR and cystic fibrosis: In a subsequent study, we demonstrated that exposure of F508del CF HBE cultures to BALF from CF children enhanced CFTR activity (Figure 2A) and maturation (Figure 2B) resulting from treatment with the CFTR corrector VX-661 and the potentiator VX-770 [32], similar to the potentiating effect of SMM on CFTR rescue [58].