GC and viral infectious disease: Despite of our findings of an IFN-GC synergy, the disruptive role of GC in IFN signaling is thought to interfere with IFN therapy in treating viral infections.40 We would attribute the strong synergy between IFN and GC despite of their functional conflicts partly to the use of inhaled IFN instead of intravenous or subcutaneous delivery methods in this cohort.