TNF and coinfection: ,46 Along these lines, our data from the co-infection experiments using S. aureus and H1N1 showed that in the presence of bacteria, at least some pro-inflammatory cytokines (i.e., IL-1β, IL-6, and TNF-α) and type II interferon IFN-γ are elevated on the protein level by H1N1 in M2-MDMs by tendency.