In AEP−/− mice, significant inhibition of cytokine and chemokine secretion associated with influenza virus-induced pneumonia, including keratinocyte chemo-attractant (KC), interleukin 6 (IL-6), and interleukin 12 (IL-12), was detected compared to wt mice (Figure 1A). This evidence concerns the gene IL6 and susceptibility to pneumonia measurement.