"Look over there!" Nanoparticles reduce inflammation by distracting the immune system
It's a classic movie trope, someone distracts the guards while our hero sneaks past. A team of researchers at the University of Michigan has deployed the same tactic to reduce inflammation in the body, by using nanoparticles that distract immune cells from negatively inflaming an injury site.
As with many scientific discoveries, this finding came entirely by accident. The team's original research focus was to develop new ways of targeted drug delivery using nanoparticles. But as the experiments progressed they discovered immune cells, called neutrophils, appearing and stopping the plastic nanoparticles from reaching the desired targets.
"The 'oh my God' of horror about our particle turned into an excitement over these particles doing something to cells that had not previously been explored," says Omolola Eniola-Adefeso, leader of the research. "These cool interactions between cells and particles got in the way of either one being able to do what they wanted to do."
Neutrophils are like the first-responders of the immune system. These cells are incredibly abundant and when not functioning correctly can cause excessive inflammation, exacerbating diseases such as sepsis and hardening of the arteries.
"Neutrophils are the first line of defense," says Eniola-Adefeso. "They are the most active and the most optimized to mount an inflammatory response. They're the underdogs of white blood cells, and we're seeing that maybe we need to pay more attention to them."
Setting up a new experiment the team observed the effect of injecting these nanoparticles into mice with acute lung injury. The results showed that the nanoparticles reduced congregation of the inflammation-causing neutrophils at the injury site by nearly 50 percent. The particles were then identified as being diverted to the liver, which removes them from circulation.
As well as offering a new investigative pathway for treating inflammatory diseases stemming from excessive neutrophil activity, this research also offers data that will help enhance future nanoparticle drug delivery systems.
The research was published in the journal Nano Letters.
Source: University of Michigan