MAVS-/- MEF Cell Infection Assay

MAVS−/− MEF cells as described23 (link) were cultured in DMEM medium supplemented with FBS (fetal bovine serum; 10%, ExCell Bio, FSP500), penicillin (100 U ml⁻¹) and streptomycin (100 μg ml⁻¹). HEK 293T cells were as described23 (link) and were grown in DMEM medium supplemented with 10% calf serum and antibiotics. Recombinant virus VSV-ΔM51-GFP (ref. 42 (link)) was amplified in Vero cells18 (link) and used with a multiplicity of infection=1. For VSV infection, MAVS−/− MEF cells were seeded in 12-well plates at a density of 1 × 10⁵ cells per well. Before incubation with 0.5 ml VSV in DMEM medium MEF cells were washed once with PBS. One hour after incubation, equal volume of DMEM with 20% FBS and antibiotics was added to the cells. Twenty-four hours after infection, cells were harvested for following analysis. Sendai virus (Cantell strain) was from Charles River Laboratories and used at a concentration of 100 HA units ml⁻¹.