Collectively, these data support the idea that TNF plays an immunoregulatory role following IAV infection at a number of points: early after infection (by d 7) to mitigate lung damage, later (d10) to attenuate peak CD8+ T cell response magnitude, and thereafter to drive the contraction [14, 36] of the IAV-specific CD8+ T cell response. This evidence concerns the gene TNF and infection.