Correcting multiple defects of mutant CFTR with small molecule compounds has been the goal of an increasing number of recent
Cystic Fibrosis (CF) drug discovery programmes. However, the mechanism of action (MoA) by which these molecules restore mutant
CFTR is still poorly understood, in particular of CFTR correctors, i.e., compounds rescuing to the cells surface the most prevalent
mutant in CF patients - F508del-CFTR. However, there is increasing evidence that to fully restore the multiple defects associated with
F508del-CFTR, different small molecules with distinct corrective properties may be required.
Towards this goal, a better insight into MoA of correctors is needed and several constraints should be addressed. The methodological approaches
to achieve this include: 1) testing the combined effect of compounds with that of other (non-pharmacological) rescuing strategies
(e.g., revertants or low temperature); 2) assessing effects in multiple cellular models (non-epithelial vs epithelial, non-human vs human,
immortalized vs primary cultures, polarized vs non polarized, cells vs tissues); 3) assessing compound effects on isolated CFTR
domains (e.g., compound binding by surface plasmon resonance, assessing effects on domain folding and aggregation); and finally 4) assessing
compounds specificity in rescuing different CFTR mutants and other mutant proteins.
These topics are reviewed and discussed here so as to provide a state-of-the art review on how to combine multiple ways of rescuing mutant
CFTR to the ultimate benefit of CF patients.