In bacterial and viral infections NOD2 through the activation of NF-κB, MAPK and caspase-1 pathways, lead to increase expression of proinflammatory cytokines, including IL-1β, tumor necrosis factor-alpha (TNFα), IL-6, IL-12p40, CC-chemokine ligand 2, IL-8, CXC-chemokine ligand 2 and various antimicrobial agents such as defensins. This evidence concerns the gene TNF and viral infectious disease.