IL-1 and IL-23, which may be derived in part from keratinocytes, were required for the induction of IL-17A following S. aureus infection of mechanically injured skin, consistent with the important role of these 2 cytokines in the induction of IL-17A in inflammation, infections, and wound healing (16, 18, 19, 34). The gene discussed is IL17A; the disease is infection.