Figure 4.

AFB₁ promotes SIV replication and lung damage in mice. Anesthetized mice were infected intranasally with 1000 TCID₅₀ of SIV or PBS on d 1, d 7, and d 14; injected intraperitoneally with various concentrations of AFB₁ daily; and sacrificed at 15 days post infection (dpi). (A) Viral titers in the lung homogenates were determined by TCID₅₀ on MDCK cells at 2 and 6 dpi. Data are shown as mean log₁₀ TCID₅₀ per gram of lung for three mice per group. The lung tissues were harvested at 15 dpi to assess viral replication as measured by (B) viral M mRNA and (C) NP levels. (D) Comparison of weight change expressed as a percentage of starting weight. (E) The lung index was calculated as the ratio of lung weight and body weight. (F) Representative images taken from nine mice in six groups as indicated. The areas of hemorrhage are denoted with the blue arrows. (G) Pathological changes in lungs. The mouse lungs were removed at 15 dpi, sectioned and stained with H&E for histological examination. Representative images from nine mice in each group were obtained at 200 × magnification. Data are presented as the means ± SEM of nine mice in each group; Different lowercase letters indicate significant differences (P < 0.05). ^{*, #}P < 0.05, ^{**, ##}P < 0.01, ns, not significant.