These tools will no longer be maintained as of December 31, 2024. Archived website can be found here. PubMed4Hh GitHub repository can be found here. Contact NLM Customer Service if you have questions.


Pubmed for Handhelds

PUBMED FOR HANDHELDS

Search MEDLINE/PubMed

  • Title: Cryoconserved shielded and EGF receptor targeted DNA polyplexes: cellular mechanisms.
    Author: von Gersdorff K, Ogris M, Wagner E.
    Journal: Eur J Pharm Biopharm; 2005 Jul; 60(2):279-85. PubMed ID: 15939238.
    Abstract:
    Recently, cryoconservable polyethylene glycol (PEG)-shielded and epidermal growth factor receptor (EGFR)-targeted polyplexes (EGF+ polyplexes) were engineered in our laboratory for tumor-directed transfer and expression of DNA. Here, we further analyzed specificity and kinetics of EGFR-mediated cellular uptake of these polyplexes. Similar to our previous results, EGF+ polyplexes significantly enhanced the transfection efficiency as compared to polyplexes without EGF (EGF- polyplexes) in HUH-7 hepatoma cells and Renca-EGFR renal carcinoma cells. EGF+ polyplexes rapidly associated with the cells within 30 min of exposure, and binding of EGF+ polyplexes to the cells after 4 h was significantly higher than that of EGF- polyplexes. In the presence of free EGF, both cell association and transfection efficiency of EGF+ polyplexes were markedly reduced indicating that these effects were primarily mediated via ligand receptor interaction. Fluorescence microscopy revealed that the cell-associated EGF+ polyplexes aggregated to micrometer sized clusters, resembling typical clustering of receptors upon ligand binding. In conclusion, EGFR-targeting enhances transfection efficiency due to accelerated and increased cell association followed by aggregation of the bound EGF+ polyplexes.
    [Abstract] [Full Text] [Related] [New Search]