Multifunctional CPP Polymer System for Tumor-Targeted pDNA and siRNA Delivery

  • Christian Dohmen
  • Ernst Wagner
Part of the Methods in Molecular Biology book series (MIMB, volume 683)


Cell-penetrating peptides (CPPs) are a very interesting class of molecules to be introduced in gene and siRNA vectors. They can be used to overcome one of the biggest hurdles in gene and siRNA delivery in vitro and in vivo, the transfer across cell membranes. This chapter describes protocols for the synthesis and biological evaluation of a polylysine-based polymer. In this carrier system, melittin is used as CPP with a high activity to disrupt membranes. pH-Labile masking is applied to render the lytic activity specific for intracellular acidic endolysosomal organelles.

Key words

Endosomal release Nonviral vector Plasmid DNA Polymer Polyplex RNA interference siRNA 



The described work was supported by DFG SFB486, Excellence Cluster “Nanosystems Initiative Munich (NIM)” and the EC project GIANT.


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Copyright information

© Springer Science+Business Media, LLC 2011

Authors and Affiliations

  • Christian Dohmen
    • 1
  • Ernst Wagner
    • 2
  1. 1.Department of Pharmacy, Pharmaceutical Biotechnology, Centre for Drug ResearchLudwig-Maximilians-UniversitätMunichGermany
  2. 2.Chair, Pharmaceutical Biotechnology Department of Pharmacy, Centre for Drug ResearchLudwig-Maximilians-UniversitätMunichGermany

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