USP18 and myeloid sarcoma: Since type 1 interferons (IFN) are known to induce IL10 and CD274 (32), we next examined gene expression of the type 1 IFN-induced response genes MX1 and USP18. No difference in the expression levels of these two genes between the pregnant MS patients and untreated patients were observed, suggesting that IL10 and PDL1 expression were not induced by endogenous type 1 IFN (Figures 2D, E).