Send to

Choose Destination
Small. 2017 Jul;13(27). doi: 10.1002/smll.201700072. Epub 2017 May 22.

A Poly(Propyleneimine) Dendrimer-Based Polyplex-System for Single-Chain Antibody-Mediated Targeted Delivery and Cellular Uptake of SiRNA.

Author information

Department of Neurosurgery, Section Experimental Neurosurgery and Tumor Immunology, University Hospital Carl Gustav Carus, TU Dresden, Fetscherstraße 74, 01307, Dresden, Germany.
Leibniz Institute of Polymer Research Dresden, Hohe Straße 6, 01069, Dresden, Germany.
German Cancer Consortium (DKTK), Partner Site Dresden German Cancer Research Center (DKFZ) Heidelberg, German and National Center for Tumor Diseases (NCT), 01307, Dresden, Germany.
Rudolf-Boehm-Institute for Pharmacology and Toxicology, Clinical Pharmacology, University Medicine Leipzig, Härtelstraße 16-18, 04107, Leipzig, Germany.


Therapeutics based on small interfering RNAs (siRNAs) offer a great potential to treat so far incurable diseases or metastatic cancer. However, the broad application of siRNAs using various nonviral carrier systems is hampered by unspecific toxic side effects, poor pharmacokinetics due to unwanted delivery of siRNA-loaded nanoparticles into nontarget organs, or rapid renal excretion. In order to overcome these obstacles, several targeting strategies using chemically linked antibodies and ligands have emerged. This study reports a new modular polyplex carrier system for targeted delivery of siRNA, which is based on transfection-disabled maltose-modified poly(propyleneimine)-dendrimers (mal-PPI) bioconjugated to single chain fragment variables (scFvs). To achieve targeted delivery into tumor cells expressing the epidermal growth factor receptor variant III (EGFRvIII), monobiotinylated anti-EGFRvIII scFv fused to a Propionibacterium shermanii transcarboxylase-derived biotinylation acceptor (P-BAP) is bioconjugated to mal-PPI through a novel coupling strategy solely based on biotin-neutravidin bridging. In contrast to polyplexes containing an unspecific control scFv-P-BAP, the generated EGFRvIII-specific polyplexes are able to exclusively deliver siRNA to tumor cells and tumors by receptor-mediated endocytosis. These results suggest that receptor-mediated uptake of otherwise noninternalized mal-PPI-based polyplexes is a promising avenue to improve siRNA therapy of cancer, and introduce a novel strategy for modular bioconjugation of protein ligands to nanoparticles.


poly(propyleneimine); polyplexes; siRNA; single chain antibodies; targeted delivery


Supplemental Content

Full text links

Icon for Wiley
Loading ...
Support Center