In this study, we showed that Nef reduced lung-capillary permeability, down-regulated the production of cytokines (IL-1β, IL-6, TNF-α, and IL-10) and inhibited the activation of the NF-κB signaling pathway in mice with lipopolysaccharide (LPS)-induced ARDS. This evidence concerns the gene NFKB1 and acute respiratory distress syndrome.