Abstract

Available corrector drugs are unable to effectively rescue the folding defects of CFTR-ΔF508 (or CFTR-F508del), the most common disease-causing mutation of the cystic fibrosis transmembrane conductance regulator, a plasma membrane (PM) anion channel, and thus to substantially ameliorate clinical phenotypes of cystic fibrosis (CF). To overcome the corrector efficacy ceiling, here we show that compounds targeting distinct structural defects of CFTR can synergistically rescue mutant expression and function at the PM. High-throughput cell-based screens and mechanistic analysis identified three small-molecule series that target defects at nucleotide-binding domain (NBD1), NBD2 and their membrane-spanning domain (MSD) interfaces. Although individually these compounds marginally improve ΔF508-CFTR folding efficiency, function and stability, their combinations lead to ~50–100% of wild-type-level correction in immortalized and primary human airway epithelia and in mouse nasal epithelia. Likewise, corrector combinations were effective against rare missense mutations in various CFTR domains, probably acting via structural allostery, suggesting a mechanistic framework for their broad application.

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The datasets generated during and/or analyzed during the current study are available from the corresponding author on reasonable request.

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Acknowledgements

The authors are grateful to the individuals who volunteered to participate in this study. We thank D. C. Gruenert for the parental CFBE41o- cell line; W. E. Finkbeiner for supplying HBE cells, J. Riordan and the Cystic Fibrosis Foundation for the 660 antibody, P. Thomas for providing vectors encoding some of the CFTR2 mutants and members of the Cystic Fibrosis Folding Consortium for advice. This work was supported by Vaincre La Mucoviscidose to A.E. and I.S.-G., the Canadian Institutes of Health Research (MOP-142221 to G.L.L. and PJT-153095 to G.V., E.M., and G.L.L.), National Institute of Diabetes & Digestive & Kidney Diseases (5R01DK075302 to G.L.L.) and the Cystic Fibrosis Foundation Therapeutics to G.L.L. as well as Cystic Fibrosis Canada to G.L.L. We acknowledge the Canada Foundation for Innovation for infrastructure support: Bruker UltrafleXtreme MALDI-TOF/TOF system (grant no. 32616, awarded to G. Multhaup and G.L.L.); BIACORE T200 SPR system (grant no. 228340 awarded to G. Multhaup). R.G.A. is a recipient of the Fonds de Recherche du Québec Santé (FRQS) Doctoral Training Scholarship. G.L.L. is a Canada Research Chair.

Author information

Affiliations

  1. Department of Physiology, McGill University, Montréal, Quebec, Canada

    • Guido Veit
    • , Haijin Xu
    • , Radu G. Avramescu
    • , Miklos Bagdany
    • , Lenore K. Beitel
    • , Ariel Roldan
    •  & Gergely L. Lukacs
  2. Institut Necker-Enfants Malades (INEM)–INSERM U1151, Paris, France

    • Elise Dreano
    • , Aleksander Edelman
    •  & Isabelle Sermet-Gaudelus
  3. SPR-MS Facility, McGill University, Montréal, Quebec, Canada

    • Mark A. Hancock
  4. Genomic Institute of the Novartis Research Foundation, San Diego, CA, USA

    • Cecilia Lay
    • , Wei Li
    • , Katelin Morin
    • , Sandra Gao
    • , Puiying A. Mak
    • , Edward Ainscow
    • , Anthony P. Orth
    • , Peter McNamara
    •  & William G. Barnes
  5. Department of Otolaryngology - Head and Neck Surgery, McGill University, Montréal, Quebec, Canada

    • Saul Frenkiel
  6. Adult Cystic Fibrosis Clinic, Montreal Chest Institute, McGill University, Montréal, Quebec, Canada

    • Elias Matouk
  7. Department of Biochemistry, McGill University, Montréal, Quebec, Canada

    • Gergely L. Lukacs
  8. Groupe de Recherche Axé sur la Structure des Protéines (GRASP), McGill University, Montréal, Quebec, Canada

    • Gergely L. Lukacs

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Contributions

The overall design of the study was by G.V., W.G.B. and G.L.L.; G.V., H.X., E.D., R.G.A., M.B., L.K.B., C.L., W.L., K.M., S.G., P.A.M., and E.A. performed experiments and analyzed the results; A.R. cloned and purified the avi-tagged NBD1 variants; M.A.H. performed the SPR studies; S.F. and E.M. collected the patient samples for HNE isolation; A.E. and I.S.-G. designed and directed the mouse studies; A.P.O., P.M. and W.G.B. designed and directed the HTS. The manuscript was primarily written by G.V. and G.L.L. with input from all authors.

Competing interests

C.L., W.L., K.M., S.G., P.A.M., F.J.K., E.A., A.J.O., P.M. and W.G.B. are employees of the Genomics Institute of the Novartis Research Foundation. I.S.-G. has been principal investigator in Vertex initiated clinical trials, received a Vertex Pharmaceuticals Innovation Award and served as a scientific advisory board member for Vertex Pharmaceuticals. G.L.L. is a member of the Scientific Advisory Board of Proteostasis Therapeutics Inc. All other authors declare no competing financial or non-financial interests.

Corresponding authors

Correspondence to Guido Veit or Gergely L. Lukacs.

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https://doi.org/10.1038/s41591-018-0200-x