IFN signaling has disparate effects on in vivo LPS stimulation and Gram-negative bacterial infection.

A) Differentiated THP-1 cells and B) BMDMs were infected with live Bc for the indicated times before RNA extraction and RT-PCR for given genes. Data show relative mRNA expression to unstimulated cells using Hprt as housekeeping gene; n = 5, representative of two experiments C) Littermate control WT (n = 13) and Ifnar1^-/- (n = 10) mice were injected intraperitoneally with 10 mg/kg of LPS and mice were weighed twice a day for 7 days. D, E) Lightly anesthetized, littermate control WT (n = 10) and Ifnar1^-/- (n = 10) mice were infected with 5x10⁶ CFUs of Bc via intranasal instillation. D) Mice were weighed every 12 h for 5 days. E) Broncho-alveolar lavages were performed 16 h post-infection and bacteria were enumerated using high-content imaging; all in vivo experiments are shown as a combination of two independent experiments C) ** = p≤0.01 by Mantel-Cox test; D, E) ** = p≤0.01, **** = p≤0.0001 by Mann-Whitney U test.