Blocking OX40 engagement has been shown to prevent immune‐mediated lung damage in a sublethal influenza infection model by eliminating the influenza‐induced CD4+ and CD8+ T‐cell infiltration within the lung (Kopf et al, 1999; Humphreys et al, 2003; Croft, 2010). The gene discussed is TNFRSF4; the disease is influenza.