Abstract 1143: Novel Glycopolymers for Nuclear Delivery of Transcription Factor Decoys in the Heart
Introduction: Nuclear factor-kappaB (NF-κB) is a key player in many pathological states including infarct development after cardiac ischemia-reperfusion (I/R). Increased cell survival after cardiac I/R has been achieved through blockade of NF-κB activation by oligonucleotide (ODN) decoys. The goal of this work was to demonstrate efficient delivery of ODN decoys using novel polyglycoamidoamine (PGAA) glycopolymers that combine low cytotoxicity with high transfection efficiency.
Methods: Transfection of NF-κB ODN decoys using PGAA polymer was done in vitro using H9C2 cells. Fluorescently labeled ODN/PGAA was delivered in vivo by intraventricular or pericardial injection. Transfection efficiency and distribution was evaluated by fluorescence microscopy.
Results: We show that the PGAA/ODN (IC50 = 2.8 μg DNA) achieves blockade of NF-κB activation at 7-fold lower dosage relative to ODN decoy alone (IC50 = 20 μg DNA). In H9C2 cells, the nuclear transfection efficiency was 80%. Delivery of the ODN/PGAA to the heart in vivo was most efficient by pericardial injection resulting in nearly transmural transfection of the myocardium. The delivered polyplex achieved physiological effect without exhibiting toxicity.
Conclusions: This work demonstrates use of PGAA polymers to deliver ODN decoys to cells both in vitro and in vivo. These polymers act through formation of nanoscale “polyplexes” with ODN decoys and enhance cellular uptake via endocytosis. These novel glycopolymers offer an approach for delivery of DNA that complements traditional genetically engineered mice and may be appropriate for translational development of therapeutic DNA delivery technologies.