Epidermal cells help coordinate leukocyte migration during inflammation through fatty acid-fueled matrix metalloproteinase production

In addition to satisfying the metabolic demands of cells, mitochondrial metabolism helps regulate immune cell function. To date, such cell-intrinsic metabolic-immunologic cross-talk has only been described operating in cells of the immune system. Here we show that epidermal cells utilize fatty acid -oxidation to fuel their contribution to the immune response during cutaneous inflammation. By live imaging metabolic and immunological processes within intact zebrafish embryos during cutaneous inflammation, we uncover a mechanism where elevated -oxidation-fueled mitochondria-derived reactive oxygen species within epidermal cells helps guide matrix metalloproteinase-driven leukocyte recruitment. This mechanism requires the activity of a zebrafish homolog of the mammalian mitochondrial enzyme, Immunoresponsive gene 1. This study describes the first example of metabolic reprogramming operating within a non-immune cell type to help control its contribution to the immune response. Targeting of this metabolic-immunologic interface within keratinocytes may prove useful in treating inflammatory dermatoses.

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Hall CJ, Boyle RH, Sun X, Wicker SM, Misa JP, Krissansen GW, Print CG, Crosier KE, Crosier PS