Impact of Locally Administered Carboxydextran-Coated Super-Paramagnetic Iron Nanoparticles on Cellular Immune Function.

Abstract

Interstitially-administered iron oxide particles are currently used for inter-operative localization of sentinel lymph nodes (SLNs) in cancer staging. Several studies have described concerns regarding the cellular accumulation of iron oxide nanoparticles relating them to phenotype and function deregulation of macrophages, impairing their ability to mount an appropriate immune response once an insult is present. This study aimed to address what phenotypic and functional changes occur during lymphatic transit and accumulation of these particles. Data shows that 60 nm carboxydextran-coated iron nanoparticles use a non-cellular mechanism to reach the draining LN and that their accumulation in macrophages induces transient phenotypic and functional changes. Nevertheless, macrophages recover their baseline levels of response within 7 days, and are still able to mount an appropriate response to bacterially-induced inflammation.