Unexpected interactions of nanoparticles with endothelial and epithelial cells

Nanoparticles regardless as subjects of nanotoxicity or nanomedicine studies will inevitably interact with endothelial and epithelial cells. In the case of nanomedicine, while these cells are usually not the intended target, nanoparticles introduced via circulation would interact with them before even beginning to act on the target cells or tissues. It is therefore important to understand the effects of these nanoparticles on these cells. Similarly, for nanomaterials that are exposed to skin or via inhalation or ingestion, the cell types would be epithelial in nature. Using generic and commonly found non-decorated nanomaterials like TiO₂, silica, silver, hydroxyapatite nanoparticles, we discovered interesting new effects and solved their mechanisms. We discovered that nanoparticles can cause endothelial leakiness (NanoEL) in vitro and in vivo by finding its way into the spaces (adherens junctions) between endothelial cells, disrupts the homophillic interactions of VE-Cadherin and trigger the signaling pathway that leads to micron sized gaps between endothelial cells. We also discovered that nanoparticles can inhibit epithelial cell migration by targeting and disrupting microtubules. This increases focal adhesion at the interface of surfaces and transmit to increased cell traction.