FIG 1.

Evaluation of the ability of 1E4 to confer protection in naive recipient SCID mice against C. burnetii aerosol infection by comparing splenomegaly, bacterial burden in the spleen and lung, and pathological changes in the lung with control mice at 14 days postinfection. (A) Splenomegaly was measured by spleen weight as a percentage of body weight. (B) Bacterial burden in the spleen was determined by real-time PCR and reported as log₁₀ of C. burnetii com1 gene copy numbers. (C) Bacterial burden in the lung. (D) Pathological changes in the lung. (E) Inflammation score in the lung. Lungs (1 section per mouse) were scored for interstitial inflammation (macrophages and neutrophils in interalveolar septum and alveolar spaces) according to the following scale: 0, none (no accumulations of neutrophils and macrophages); 1, few small scattered accumulations of neutrophils and macrophages; 2, mild to moderate accumulations of macrophages and neutrophils which affects less than 10% of lung parenchyma; 3, moderate to large accumulations of macrophages and neutrophils which affects ≥10% of lung parenchyma. The data presented in each group are the averages with standard deviations from four mice. **, P < 0.01; ***, P < 0.001.