Decreased binding to proteins and cells of polymeric gene delivery vectors surface modified with a multivalent hydrophilic polymer and retargeting through attachment of transferrin

Philip R. Dash, Martin L. Read, Kerry D. Fisher, Kenneth A. Howard, Margreet Wolfert, David Oupicky, Vladimir Subr, Jiri Strohalm, Karel Ulbrich, Leonard W. Seymour

Research output: Contribution to journalArticle

162 Scopus citations

Abstract

Binding of serum proteins to polyelectrolyte gene delivery complexes is thought to be an important factor limiting bloodstream circulation and restricting access to target tissues. Protein binding can also inhibit transfection activity in vitro. In this study a multivalent reactive hydrophilic polymer has been used to inhibit protein binding. This polymer is based on poly-[N-(2-hydroxypropyl)methacrylamide] (pHPMA) bearing pendent oligopeptide (Gly-Phe-Leu-Gly) side chains terminated in reactive 4- nitrophenoxy groups (8.6 mol%). The polymer reacts with the primary amino groups of poly(L-lysine) (pLL) and produces a hydrophilic coating on the surface of pLL-DNA complexes (as measured by fluorescamine). The resulting pHPMA-coated complexes show a decreased surface charge (from +14 mV for pLL·DNA complexes to -25 mV for pHPMA-modified complexes) as measured by ζ potential analysis. The pHPMA-coated complexes also show a slightly increased average diameter (approximately 90 nm compared with 60 nm for pLL·DNA complexes) as viewed by atomic force and transmission electron microscopy and around 100 nm as viewed by photon correlation spectroscopy. They are completely resistant to protein interaction, as determined by turbidometry and SDS-polyacrylamide gel electrophoresis analysis of complexes isolated from plasma, and show significantly decreased nonspecific uptake into cells in vitro. Spare reactive ester groups can be used to conjugate targeting ligands (e.g. transferrin) on to the surface of the complex to provide a means of tissue-specific targeting and transfection. The properties of these complexes therefore make them promising candidates for targeted gene delivery, both in vitro and potentially in vivo.

Original languageEnglish (US)
Pages (from-to)3793-3802
Number of pages10
JournalJournal of Biological Chemistry
Volume275
Issue number6
DOIs
StatePublished - Feb 11 2000

ASJC Scopus subject areas

  • Biochemistry
  • Molecular Biology
  • Cell Biology

Fingerprint Dive into the research topics of 'Decreased binding to proteins and cells of polymeric gene delivery vectors surface modified with a multivalent hydrophilic polymer and retargeting through attachment of transferrin'. Together they form a unique fingerprint.

  • Cite this