title: Identification of siRNA delivery enhancers by a chemical library screen.
abstract: Most delivery systems for small interfering RNA therapeutics depend on endocytosis and release from endo-lysosomal compartments. One approach to improve delivery is to identify small molecules enhancing these steps. It is unclear to what extent such enhancers can be universally applied to different delivery systems and cell types. Here, we performed a compound library screen on two well-established siRNA delivery systems, lipid nanoparticles and cholesterol conjugated-siRNAs. We identified fifty-one enhancers improving gene silencing 2-5 fold. Strikingly, most enhancers displayed specificity for one delivery system only. By a combination of quantitative fluorescence and electron microscopy we found that the enhancers substantially differed in their mechanism of action, increasing either endocytic uptake or release of siRNAs from endosomes. Furthermore, they acted either on the delivery system itself or the cell, by modulating the endocytic system via distinct mechanisms. Interestingly, several compounds displayed activity on different cell types. As proof of principle, we showed that one compound enhanced siRNA delivery in primary endothelial cells in vitro and in the endocardium in the mouse heart. This study suggests that a pharmacological approach can improve the delivery of siRNAs in a system-specific fashion, by exploiting distinct mechanisms and acting upon multiple cell types.
authors.affiliation: Max Planck Institute of Molecular Cell Biology and Genetics, Pfotenhauerstrasse 108 01307, Dresden, Germany INSERM U1065, Centre Méditerranéen de Médecine Moléculaire C3M, Nice, France; Université de Nice Sophia-Antipolis, Nice, France.
authors.forename: Jerome
authors.initials: J
authors.lastname: Gilleron
authors.affiliation: Max Planck Institute of Molecular Cell Biology and Genetics, Pfotenhauerstrasse 108 01307, Dresden, Germany.
authors.forename: Prasath
authors.initials: P
authors.lastname: Paramasivam
authors.affiliation: Max Planck Institute of Molecular Cell Biology and Genetics, Pfotenhauerstrasse 108 01307, Dresden, Germany.
authors.forename: Anja
authors.initials: A
authors.lastname: Zeigerer
authors.affiliation: Alnylam Pharmaceuticals, Cambridge, MA, USA.
authors.forename: William
authors.initials: W
authors.lastname: Querbes
authors.affiliation: Max Planck Institute of Molecular Cell Biology and Genetics, Pfotenhauerstrasse 108 01307, Dresden, Germany.
authors.forename: Giovanni
authors.initials: G
authors.lastname: Marsico
authors.affiliation: Max Planck Institute of Molecular Cell Biology and Genetics, Pfotenhauerstrasse 108 01307, Dresden, Germany.
authors.forename: Cordula
authors.initials: C
authors.lastname: Andree
authors.affiliation: Max Planck Institute of Molecular Cell Biology and Genetics, Pfotenhauerstrasse 108 01307, Dresden, Germany.
authors.forename: Sarah
authors.initials: S
authors.lastname: Seifert
authors.affiliation: Max Planck Institute of Molecular Cell Biology and Genetics, Pfotenhauerstrasse 108 01307, Dresden, Germany.
authors.forename: Pablo
authors.initials: P
authors.lastname: Amaya
authors.affiliation: Max Planck Institute of Molecular Cell Biology and Genetics, Pfotenhauerstrasse 108 01307, Dresden, Germany.
authors.forename: Martin
authors.initials: M
authors.lastname: Stöter
authors.affiliation: Lomonosov Moscow State University, Chemistry Department, Leninskie Gory, 1/3, Moscow 119991, Russia Skolkovo Institute of Science and Technology, 100 Novaya str., Skolkovo, Odinsovsky district, Moscow 143025, Russia.
authors.forename: Victor
authors.initials: V
authors.lastname: Koteliansky
authors.affiliation: Department of Chemical Biology, Max-Planck-Institute of Molecular Physiology, Otto-Hahn-Strasse 11, 44227 Dortmund, Germany Chemical Biology, Faculty of Chemistry and Chemical Biology, TU Dortmund, Otto-Hahn-Strasse 6, 44221 Dortmund, Germany.
authors.forename: Herbert
authors.initials: H
authors.lastname: Waldmann
authors.affiliation: Alnylam Pharmaceuticals, Cambridge, MA, USA.
authors.forename: Kevin
authors.initials: K
authors.lastname: Fitzgerald
authors.affiliation: Max Planck Institute of Molecular Cell Biology and Genetics, Pfotenhauerstrasse 108 01307, Dresden, Germany.
authors.forename: Yannis
authors.initials: Y
authors.lastname: Kalaidzidis
authors.affiliation: Alnylam Pharmaceuticals, Cambridge, MA, USA.
authors.forename: Akin
authors.initials: A
authors.lastname: Akinc
authors.affiliation: Alnylam Pharmaceuticals, Cambridge, MA, USA.
authors.forename: Martin A
authors.initials: MA
authors.lastname: Maier
authors.affiliation: Alnylam Pharmaceuticals, Cambridge, MA, USA.
authors.forename: Muthiah
authors.initials: M
authors.lastname: Manoharan
authors.affiliation: Max Planck Institute of Molecular Cell Biology and Genetics, Pfotenhauerstrasse 108 01307, Dresden, Germany.
authors.forename: Marc
authors.initials: M
authors.lastname: Bickle
authors.affiliation: Max Planck Institute of Molecular Cell Biology and Genetics, Pfotenhauerstrasse 108 01307, Dresden, Germany Zerial@MPI-CBG.de.
authors.forename: Marino
authors.initials: M
authors.lastname: Zerial
mesh_terms: D000818:Animals; D002478:Cells, Cultured; D002784:Cholesterol; D011992:Endosomes / Q000378:metabolism; D042783:Endothelial Cells / Q000378:metabolism; D005347:Fibroblasts / Q000378:metabolism; D006367:HeLa Cells; D022781:Hepatocytes / Q000378:metabolism; D006801:Humans; D008055:Lipids; D051379:Mice; D053758:Nanoparticles; D034622:RNA Interference; D034741:RNA, Small Interfering / Q000008:administration & dosage* / Q000378:metabolism; D054852:Small Molecule Libraries
chemical_list: D008055:Lipids; D034741:RNA, Small Interfering; D054852:Small Molecule Libraries; D002784:Cholesterol