Induction of IFNλ by <i>S. aureus</i> USA300 inhibits bacterial clearance.

<p>(A) qRT-PCR analysis of IFNλ mRNA in BMDCs stimulated with heat killed USA300, µ ± SD. (B) ELISA analysis of IFNλ in BAL of WT mice following 4 and 18 hours of infection with USA300. (C) Numbers (CFU) of USA300 recovered from BAL of WT and IL-28R^−/− mice following 4 and 18 hours of infection. (D) Numbers (CFU) of USA300 recovered from lung tissue of WT and IL-28R^−/− mice following 4 and 18 hours of infection. (E) Trichrome stained lungs from WT and IL-28R^−/− mice following and 18 hour USA300 infection (original magnification 100x, insert 400x). (F) Numbers of dendritic cells (DC), macrophages (MAC), and neutrophils in BAL of WT and IL-28R^−/− in unstimulated (NS) mice or following 4 or 18 hours of infection. (G) Numbers of dendritic cells (DC), macrophages (MAC), and neutrophils in lung tissue of WT and IL-28R^−/− in unstimulated (NS) mice or following 4 or 18 hours of infection. Data are representative of at least 2 independent experiments.