IL4 and infection: Monocytes were differentiated for 3 days (37 °C, 5% CO2) in MGM with or without 25 ng/ml recombinant human IL-4 (PeproTech) to generate partially matured MDMΦs, then infected with DENV2 strain 16681 (a gift from G. Screaton, Oxford, UK) diluted to a multiplicity of infection (MOI) of 1 in X–VIVO10 without supplements for 90 min, followed by treatment with no iminosugar, 100 μM NB-DNJ (solubilised in PBS, gift from Oxford GlycoSciences Ltd.), or 25 μM MON-DNJ (solubilised in acidified water, gift from United Therapeutics) for 2 days.