Magnetic Capture of Autologous Mesenchymal Stem Cells Promotes the Rapid Endothelialization of Peripheral Venous Stents in Rabbits.

Abstract

The rapid development of an endothelium over venous stents is associated with improved clinical outcomes. In this study, we investigate an approach to rapidly endothelialize venous stents using magnetic cell capture. Autologous mesenchymal stem cells were generated from rabbit adipose tissue and labeled with superparamagnetic iron oxide nanoparticles. Non-magnetic control and magnetic stents were deployed in the opposite external iliac veins of rabbits. The cells were delivered into the stent lumens in the presence of external magnets. Magnetic cell capture and retention, rate of endothelization, and stenosis were evaluated histologically. We found that the cells were capable of being magnetically captured by and adhering to the magnetic stents. Their magnetic capture facilitated the development of an endothelium over the magnetic stents within 3 days. In contrast, no magnetic cell capture was observed on the control stents, and the control stents were completely bare after 3 days. We found no significant difference in stenosis between the control and magnetic stents after 30 days. In conclusion, we demonstrated that autologous adipose derived mesenchymal stem cells labeled with superparamagnetic iron oxide nanoparticles are capable of being magnetically captured to the surface of magnetic stents, improving the rate of endothelialization in a rabbit iliac vein model. STATEMENT OF SIGNIFICANCE: Venous stents are deployed to mechanically open and restore blood flow through diseased, narrowed veins. Bare metal initially contacts blood, which may provoke thrombosis and neointimal hyperplasia leading to restenosis. Current drug‑eluting stents curb smooth muscle proliferation but delay endothelial healing, while antibody‑coated endothelial progenitor cell‑capturing stents accelerate healing but require permanent, expensive bioactive coatings. We studied autologous mesenchymal stem cells tagged with superparamagnetic iron‑oxide nanoparticles, magnetically drawn onto ferromagnetic stents by an external field. In a rabbit iliac vein model, this one‑time magnetic seeding significantly increased the rate of endothelialization on magnetic stents compared to non‑magnetic controls. This approach offers a mechanically simple, coating‑free route to improve venous stenting outcomes.