Consistent with the non-significant reduction of CD4+ T-cell populations that we observed at this stage of HIV infection (Fig. 1), there were no significant decreases in IFN-γ activation due to HIV co-infection with Mtb. As expected, several cytokines and chemokines were significantly increased in the lung microenvironment due to Mtb infection, including pro-inflammatory cytokines (IL-1-β, IL-6, and TNF-α) and chemokines (MCP-1, IP-10, Eotaxin 1, and GM-CSF) and IL-12, IFN-γ, and IL-4. This evidence concerns the gene IL4 and coinfection.