As has been illustrated above, NK-92 cells in CSE- and PPD-coexposed group displayed increased proinflammatory cytokine production (IFN-α, IFN-β, IFN-gamma, and perforin), concurrent with decreased glycolytic flux and oxidative phosphorylation, which was in line with a previous study showing that GAPDH expression (glycolytic enzyme) inversely correlated with IFN-gamma production in CD4 T cells in vivo after infection with Listeria monocytogenes (Chang et al., 2013). Here, CD4 is linked to infection.