The air, especially in cities, is chock-full of particulate matter, and a group from the Chinese Academy of Sciences has investigated how the smallest of these particles affects the proteomes of lung cells.
As they report in The Journal of Applied Toxicology, the researchers led by Heqing Shen collected air samples from the roof of their building and exposed lung epithelial cells to water-soluble particulate matter with an aerodynamic diameter of less than 2.5 µm. They then characterized the proteomes of those cells using two-dimensional difference gel electrophoresis coupled with matrix-assisted laser desorption/ionization time-of-flight tandem mass spectrometry along with western blots and RT-PCR analysis.
From this, they found that 27 proteins had altered expression in the lung cells — 12 were upregulated while 15 were downregulated. The altered proteins tended to be involved in oxidative stress, metabolic disturbance, and cytoskeleton disorganization, among others.
"The results … highlight[ed] that the toxic mechanisms of PM2.5 are in fact complex and diverse," the researchers note.
Spectroscopy Now's Steve Down adds that "[a]s well as shedding light on the way that cells react when contaminated with PM2.5, the results could be used to find a set of biomarkers which signal that someone has been subjected to exposure to PM2.5 particles."