Interactions of polymeric and liposomal gene delivery systems with extracellular glycosaminoglycans: physicochemical and transfection studies

Abstract

Complexes of DNA with cationic lipids and cationic polymers are frequently used for gene transfer. Extracellular interactions of the complexes with anionic glycosaminoglycans (GAGs) may interfere with gene transfer. Interactions of GAGs with the carrier-DNA complexes were studied using tests for DNA relaxation (ethidium bromide intercalation), DNA release (electrophoresis), and transfection (pCMVbetaGal transfer into RAA smooth muscle cells). Several cationic lipid formulations (DOTAP, DOTAP/Chol, DOTAP/DOPE, DOTMA/DOPE, DOGS) and cationic polymers (fractured dendrimer, polyethylene imines 25 kDa and 800 kDa, polylysines 20 kDa and 200 kDa) were tested. Polycations condensed DNA more effectively than the monovalent lipids. Hyaluronic acid did not release or relax DNA in any complex, but it inhibited the transfection by some polyvalent systems (PEI, dendrimers, DOGS). Gene transfer by the other carriers was not affected by hyaluronic acid. Sulfated GAGs (heparan sulfate, chondroitin sulfates B and C) completely blocked transfection, except in the case of the liposomes with DOPE. Sulfated GAGs relaxed and released DNA from some complexes, but these events were not prerequisites for the inhibition of transfection. In conclusion, polyvalent delivery systems with endosomal buffering capacity (DOGS, PEI, dendrimer) were most sensitive to the inhibitory effects of GAGs on gene transfer, while fusogenic liposomes (with DOPE) were the most resistant systems.

Protective copolymers for nonviral gene vectors: synthesis, vector characterization and application in gene delivery

“…The excess positive charge of lipoplexes and polyplexes, which is required for full DNA compaction and nuclease resistance, implies strong interactions with solutes (eg blood proteins, 10 erythrocytes 2 ) and the extracellular matrix 11,12 under in vivo conditions. The mostly undesired consequences can be unintentional vector targeting, assembled vectors or their cationic component in order to confer the desired stability.…”

The role of tissue macrophages in the induction of proinflammatory cytokine production following intravenous injection of lipoplexes

“…After intravenous injection of lipoplex, plasmid DNA would be dissociated from the cationic liposomes in the blood circulation by the interaction with biological components, such as blood constituents and proteoglycans. 25,27,28 Free DNA dissociated from cationic liposomes is susceptible to degradation by nucleases in the blood and the degradation products are excreted into the urine via the kidney and distributed throughout the body. Kawabata et al 29 have demonstrated these processes after i.v.…”

Development of a novel gene delivery scaffold utilizing colloidal gold–polyethylenimine conjugates for DNA condensation

“…[1][2][3][4] Of these, a significant portion have relied upon the use of polyethylenimine (PEI) as a carrier base due to its established efficiency as a gene compaction and delivery reagent. 2,[5][6][7][8][9] PEI has the highest cationic charge density of any macromolecule and is thus conducive to DNA condensation.…”