Neutrophils (red) arrest plastic nanoparticles (green) from the bloodstream and deliver them to the liver of a live mouse for disposal. Image credit: Catherine Fromen, Cell Adhesion & Drug Delivery Lab
Researchers at the University of Michigan have shown that nanoparticles can distract neutrophils from causing inflammation, which could be helpful in treating inflammatory diseases. The immune cells carry the nanoparticles to the liver instead of causing inflammation at injury sites.
Excessive inflammation is a component of many diseases, from atherosclerosis to sepsis. In a recent study, scientists have found that an intravenous injection of nanoparticles could distract neutrophils from causing inflammation at injury sites, suggesting that nanoparticles could be useful as an anti-inflammatory treatment.
Neutrophils (red) bind to the plastic nanoparticles (green) inside a live mouse blood vessel vessel. Image credit: Catherine Fromen, Cell Adhesion & Drug Delivery Lab
“Neutrophils are the first line of defense. They are the most active and the most optimized to mount an inflammatory response,” said Omolola Eniola-Adefeso, a researcher involved in the study. “They’re the underdogs of white blood cells, and we’re seeing that maybe we need to pay more attention to them.”
Using microfluidic chips, the research team observed that neutrophils will preferentially chase and interact with nanoparticles, as a foreign body that needs to be removed, rather than stick around at an injury site and create inflammation.
The team injected the nanoparticles into the bloodstream of mice with an acute lung injury, the excessive inflammation from which can lead to a life-threatening accumulation of fluid. They found that the nanoparticles reduced the number of neutrophils at the injury site by half or more, returning the cell concentrations in the blood to those of uninjured mice.
The neutrophils carried the particles to the liver, where they were removed from the bloodstream. The team plans to examine the phenomenon further and see if the nanoparticles can redirect the immune system in other inflammatory conditions. If so, nanoparticle technologies could be a viable treatment method for a variety of inflammatory diseases.
See a neutrophil try to grab a nanoparticle in the following video:
Study in ACS Nano: Neutrophil–Particle Interactions in Blood Circulation Drive Particle Clearance and Alter Neutrophil Responses in Acute Inflammation…