Inflammation is a protective response to invading microbes and tissue damage. Upon microbe clearance from the body or completion of wound healing, the inflammatory response must be dampened down.

One set of molecules known to play a role in resolving the inflammatory response is the E-series resolvins. While analyzing the blood of several individuals to investigate the pathway by which E-series resolvins are generated, Charles Serhan and colleagues, at Harvard Medical School, Boston, identified a new 18S E-series resolvin.

Importantly, the new resolvin reduced levels of pro-inflammatory molecules and cells in a mouse model of inflammation caused by the bacterium E. coli. Further, as the new resolvin could be generated from aspirin, the authors suggest that this molecule could contribute to the beneficial effects of aspirin.