Effect of intratracheal CpG-ODN challenge on NF-κB DNA-binding activity in the lung. To evaluate the effect of CpG-ODN on the NF-κB signaling pathway, nuclear extracts of lung homogenates were analyzed using the TransAM™ ELISA kit. CpG-ODN significantly increased NF-κB DNA-binding activity, which reached the peak 24 h after the instillation. Values are the mean ± SEM; n = 5-6 for each group. *p < 0.05 compared with the PBS group. †p < 0.05 compared with the control ODN group.