Overall, these data suggest that the reduced viral load in mAb-treated animals leads to a generally reduced anti-viral/type 1 IFN signal, whereas dexamethasone treatment downregulates specific genes in some cell types, such as the pro-inflammatory cytokines Tnfsf10 and Cxcl10 in neutrophils, thereby attenuating classic features of pneumonia in animals receiving dexamethasone. This evidence concerns the gene CXCL10 and susceptibility to pneumonia measurement.