Magnetic Nanoparticle and Magnetic Field Assisted siRNA Delivery In Vitro

  • Olga Mykhaylyk
  • Yolanda Sanchez-Antequera
  • Dialechti Vlaskou
  • Maria Belen Cerda
  • Mehrdad Bokharaei
  • Edelburga Hammerschmid
  • Martina Anton
  • Christian Plank
Protocol
Part of the Methods in Molecular Biology book series (MIMB, volume 1218)

Abstract

This chapter describes how to design and conduct experiments to deliver siRNA to adherent cell cultures in vitro by magnetic force-assisted transfection using self-assembled complexes of small interfering RNA (siRNA) and cationic lipids or polymers that are associated with magnetic nanoparticles (MNPs). These magnetic complexes are targeted to the cell surface by the application of a gradient magnetic field. A further development of the magnetic drug-targeting concept is combining it with an ultrasound-triggered delivery using magnetic microbubbles as a carrier for gene or drug delivery. For this purpose, selected MNPs, phospholipids, and siRNAs are assembled in the presence of perfluorocarbon gas into flexible formulations of magnetic lipospheres (microbubbles). Methods are described how to accomplish the synthesis of magnetic nanoparticles for magnetofection and how to test the association of siRNA with the magnetic components of the transfection vector. A simple method is described to evaluate magnetic responsiveness of the magnetic siRNA transfection complexes and estimate the complex loading with magnetic nanoparticles. Procedures are provided for the preparation of magnetic lipoplexes and polyplexes of siRNA as well as magnetic microbubbles for magnetofection and downregulation of the target gene expression analysis with account for the toxicity determined using an MTT-based respiration activity test. A modification of the magnetic transfection triplexes with INF-7, fusogenic peptide, is described resulting in reporter gene silencing improvement in HeLa, Caco-2, and ARPE-19 cells. The methods described can also be useful for screening vector compositions and novel magnetic nanoparticle preparations for optimized siRNA transfection by magnetofection in any cell type.

Key words

siRNA delivery in vitro Magnetic nanoparticles Magnetic transfection vectors Microbubble Sonoporation 

Notes

Acknowledgments

We gratefully acknowledge the support from the German Research Foundation through the DFG Research Unit FOR917 (Project PL 281/3-1), from the German Federal Ministry of Education and Research through grants ZIM-KOOP “STEP-MAG,” Nanobiotechnology grants 13N8186 and 13N8538, and from the Excellence Cluster “Nanosystems Initiative Munich.” The authors would like to thank Dr. Bob Scholte for transduction of the H441 cells with eGFP and luciferase using lentiviral vectors and Dr. Christian Bergemann (chemicell GmbH, Berlin) for providing MNPs for the preparation of the MAALs. This work was supported by the European Union through the FP6-LIFESCIHEALTH Project “Improved precision of nucleic acid based therapy of cystic fibrosis” under contract no. 005213.

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Copyright information

© Springer Science+Business Media New York 2015

Authors and Affiliations

  • Olga Mykhaylyk
    • 1
  • Yolanda Sanchez-Antequera
    • 1
  • Dialechti Vlaskou
    • 1
  • Maria Belen Cerda
    • 2
  • Mehrdad Bokharaei
    • 3
  • Edelburga Hammerschmid
    • 1
  • Martina Anton
    • 1
  • Christian Plank
    • 4
  1. 1.Institute of Experimental OncologyKlinikum rechts der Isar der Technischen Universität MünchenMunichGermany
  2. 2.National Atomic Energy CommissionBuenos AiresArgentina
  3. 3.Faculty of Pharmaceutical SciencesThe University of British ColumbiaVancouverCanada
  4. 4.Institute of Experimental OncologyKlinikum rechts der Isar der Technischen Universität MünchenMunichGermany

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