The research reveals a particular immune cell is released by fat cells when an organism faces systemic stress.

For several decades a link between stress and inflammatory disease has been clear, with many chronic diseases obviously triggered into flare-ups by acute periods of stress. However, underlying this clear observation has been an unexplained paradox; hormones released by the body in the face of stress, such as cortisol and adrenaline, confer distinctly immunosuppressive effects, yet stress somehow still seems to stimulate inflammation.

"In the clinic, we have all seen super-stressful events that make inflammatory disease worse, and that never made sense to us," explains corresponding author on the study, Andrew Wang.

The new study stemmed from a novel laboratory observation. Taking blood samples from mice is an inherently stressful procedure and the researchers noticed this correlated with an increase in interleukin-6 (IL-6) levels. Increased IL-6 levels have previously been implicated in autoimmune conditions and acute stress, but exactly how it is released has not been studied.