To determine the importance of HIF1α in macrophages during pneumonia-induced sepsis, we assessed the bacterial outgrowth and dissemination of intranasally instilled K. pneumoniae during pneumonia (12 hours after inoculation) and pneumosepsis (40 hours after inoculation) in LysM-cre × Hif1αfl/fl mice and littermate (Hif1αfl/fl) controls. The gene discussed is HIF1A; the disease is susceptibility to pneumonia measurement.