ISG15 and systemic lupus erythematosus: Since miR-155 has been shown to regulate type I IFN responses by targeting IFN signaling components, we hypothesized that the reduction in lupus manifestations could be due to effects in the IFN pathway and found a reduced expression of various IFN related genes (MX1, IP10, IRF7, ISG15, IFIT3, STAT1) in PIL-/- when compared to wild type PIL+/+ [46].