Proinflammatory cytokines such as interleukin-1β (IL-1β) and tumor necrosis factor–α (TNF-α) are both strongly induced shortly after PR8 influenza infection in mice (25–27), and, notably, COUP-TF2 expression is suppressed by these same cytokines in endometrial stromal cells (28). Here, IL1B is linked to influenza.