When a patient is suffering from a clogged artery, there’s a go-to procedure: performing an angioplasty to open up the vessel and placing a tube, called a stent, inside to keep it open. Modern stents even offer the ability to release drugs to prevent future closures.
But there are downsides to these drug-eluting stents. While the medication stops the overgrowth of smooth muscle cells that cause re-narrowing—a process called neointimal hyperplasia (IH)—it also poisons the endothelial cells that form the inner wall of the blood vessel. And the presence of a physical object increases the risk of blood clots.
Shaoqin “Sarah” Gong, a Vilas Distinguished Professor of biomedical engineering and Wisconsin Institute for Discovery investigator at the University of Wisconsin-Madison, and her collaborators, Dr. K. Craig Kent and Professor Lian-Wang Guo of The Ohio State University College of Medicine, believe they’ve found a better strategy for maintaining open blood vessels in the wake of surgeries such as angioplasties or bypasses.
The collaborative team recently received a $2.4 million grant from the National Institutes of Health to develop a new, stent-free approach using nanoparticles to deliver a drug.
The four-year grant builds upon promising preliminary studies in which the Ohio State researchers identified potential drug targets and Gong, an expert in nanomedicine, devised a delivery method by engineering biomimetic nanoclusters to carry a drug to the appropriate location. The group details that preliminary work in a paper published in the September 2018 issue of Biomaterials.
By inhibiting the targeted pathways, the researchers believe they can suppress smooth muscle cell proliferation while also protecting the endothelial cells and allowing them to re-grow after surgery.
To safely deliver a drug to do that, they’ll rely on Gong’s drug-loaded nanoclusters, which are coated with a biomembrane, such as a platelet.
After doctors inject the nanoparticle through an IV, its biomembrane coating would act as a guide to take the particle to the targeted location, says Gong.
“You want to deliver your drug more specifically to the injured vasculature,” she says, explaining the advantage of this biomimetic approach (mimicking a biological mechanism).
The interdisciplinary team of investigators believes once the novel approach is fully developed, it could benefit millions of patients with various cardiovascular diseases.
At UW-Madison, Gong is also a member of the UW Carbone Cancer Center, the McPherson Eye Research Institute and the UW Institute for Clinical and Translational Research, and an affiliate of the Department of Chemistry and the Department of Materials Science and Engineering. She also earned a Kellett Mid-Career Award from UW-Madison in March 2018.
Author: Tom Ziemer