Mouse daily weight and temperature.

<p>Daily weight (g) and temperature (°C) of mock-infected C57BL/6 mice and mice infected with either MP-12 or ZH501.</p

Viral Titers.

<p>Viral titers in the serum, liver, spleen, and brain after infection with (A) MP-12 or (B) ZH501. Each point with the exception of 96 hpi in the ZH501 graph represents the mean virus titer of five mice. The 96 hpi points in the ZH501 graph represent only the 3 mice that survived until that point. Error bars for the standard deviation were removed for clarity. (C) Immunohistochemical staining for RVFV antigen in liver from a ZH501 infected mouse at 60 hpi. Intracytoplasmic viral antigen is depicted by brown staining, 10×. (D) Immunohistochemical stain of liver from a ZH501 infected mouse at 84 hpi. Intracytoplasmic viral antigen is depicted by brown staining, 20×. (E) Immunohistochemical stain of spleen for RVFV antigen from a ZH501 infected mouse at 84 hpi. The red pulp sinusoids contain numerous cells with cytoplasmic brown, granular material depicting viral antigen. There are no viral antigen positive cells in the lymphoid follicle. Note the increased lymphocytolysis depicted by pyknotic nuclei and cellular fragments, 20×. (F) Brain from a ZH501 infected animal at 84 hpi with no pathologic changes, H&E 2.5×.</p

Liver function enzymes.

<p>Alanine aminotransferase (ALT), glucose, and total bilirubin concentrations in the serum of mock (A), MP-12 (B) and ZH501 (C) infected mice. The first row provides serum ALT concentrations, the second row glucose concentrations and the third total bilirubin concentrations. Each symbol represents an individual mouse. There were five mice in each group, except at 96 hpi where only three animals had survived until this point of the study. The horizontal bar represents the mean of the mice for that group. Please note that the maximum for the Y-axis in (C)-ALT is 2000 U/L rather than 150 U/L as in (A) and (B) ALT graphs.</p

IFN-β concentration following infection.

<p>IFN-β concentration in the (A) liver, (B) spleen, and (C) brain in mice after infection. The first row represents mock infected mice, the second row represents MP-12 infected mice, and the third is ZH501 infected mice. Each symbol represents an individual mouse. There were five mice in each group with the exception of the 96 time-point for ZH501 when only three animals were surviving. The horizontal bar represents the mean of the mice for each group. Brackets indicate that the average value for ZH501 infected animals is significantly different from both mock and MP-12 infected animals.</p

Liver and spleen pathology.

<p>(A) Liver from a mock-infected mouse at 84 hpi. The liver is essentially normal H&E 20×. (B) Liver from an MP-12 infected mouse at 84 hpi. The random, small microgranulomas composed of individually-necrotic hepatocytes surrounded by small numbers of neutrophils and mononuclear cells are unrelated to the study, H&E 20×. (C) Liver from a ZH501 infected mouse at 84 hpi, showing piecemeal hepatocyte necrosis (white arrowhead), hepatocellular intranuclear eosinophilic inclusions (white arrow). Note the presence of neutrophils (black arrow) within foci of necrosis, H&E stain 40×. (D) Spleen from a mock-infected mouse at 84 hpi. The spleen is essentially normal, H&E 20×. (E) Spleen from an MP-12 infected mouse at 84 hpi. The spleen is essentially normal, H&E 20×. (F) Spleen from a ZH501 infected mouse at 84 hpi with moderate amounts of necrotic cellular debris and macrophages containing hemosiderin (brown pigment) within red pulp sinusoids, H&E 10×.</p