Yue Liu1, Ju Sheng1, Andrei Fokine1, Geng Meng1, Woong-Hee Shin1, Feng Long1, Richard J. Kuhn1, Daisuke Kihara1,2, Michael G. Rossmann1,*
Adipocytes have been suggested to be immunologically active, but their role in host defense is unclear. We observed rapid proliferation of preadipocytes and expansion of the dermal fat layer after infection of the skin by Staphylococcus aureus. Impaired adipogenesis resulted in increased infection as seen in Zfp423nur12 mice or in mice given inhibitors of peroxisome proliferator–activated receptor γ. This host defense function was mediated through the production of cathelicidin antimicrobial peptide from adipocytes because cathelicidin expression was decreased by inhibition of adipogenesis, and adipocytes from Camp−/− mice lost the capacity to inhibit bacterial growth. Together, these findings show that the production of an antimicrobial peptide by adipocytes is an important element for protection against S. aureus infection of the skin.