New nanoparticle enhances bypass grafts.

• Position: Coronary Arteries

A nanopartide delivery system that significantly may improve the success rate of coronary artery bypass grafts has been developed by a team of surgeons and biomedical engineers, reports Science Translational Medicine.

Currently, nearly half of all saphenous vein grafts (a superficial leg vein used to bypass blocked coronary arteries) fail within 18 months because of inflammation and Intlmal hyperplasia, Inward growth of cells in the vessel's Inner lining that can block blood flow to the heart. This process Is driven by signaling pathway Involving the protein MK2. A highly specific, cell-penetrating peptide-based MK2 inhibitor Is in clinical trials In Europe, but Its effectiveness is limited because it gets trapped In endosomes and lysosomes in the cell, where it is degraded.

Surgeon Colleen Brophy, biomedical engineer Craig Duvall, and their colleagues developed electrostatically complexed nanoparticles that can deliver the peptide inhibitor to vascular cells efficiently while avoiding en dosomal and lysosomal degradation.

"It's a one-time delivery to the tissue during transplant, so It's safe and limits the patient's exposure to...