When a pathogenic bacterium invades the skin, fat cells are enlisted to help to kill the microbe, finds a study in mice.

Richard Gallo at the University of California, San Diego, and his team studied fat cells beneath the skin of mice that had been infected with Staphylococcus aureus. They found that fat cells increased in size and number in the early stages of infection and near the infection site. They also observed an increased amount of an antimicrobial compound, cathelicidin, when precursor mouse and human fat cells that had not been exposed to the bacterium developed into mature cells. The microbe enhanced the production of this molecule, which in turn slowed its growth.

Mice that could not generate fat cells were more susceptible to S. aureus infection.

Science 347, 67–71 (2015)