Figure 7

BAG was detected during spore infection and enhanced LT-mediated lethality in mice. (A) Six-week-old BALB/c female mice were infected with 5× LD₅₀ of B. anthracis H9401 spores (n = 16) or injected with PBS (n = 10) into the tail vein. After 24 h, sera were isolated and filtered to remove bacilli. Genomic DNA was quantified by analyzing the signal intensity of B. anthracis 16S rRNA gene-specific PCR products. The relative amount was calculated based on a standard curve equation. Each triangle or circle represents a single experiment, and the horizontal bar indicates the mean. *P <0.05 as compared with the PBS-injected group. (B) Kaplan-Meier survival curves for BALB/c female mice injected with BAG and/or LT into the tail vein. Infliximab (1 mg) was given by intraperitoneal route before injection with LT + BAG. The percent survival was determined at 14 days after injection. Mice injected with BAG (20 μg) with LT (PA 50 μg + LF 20 μg) showed decreased survival (open diamond) when compared with LT (PA 50 μg + LF 20 μg) group (closed triangle), however, the lowered survival was recovered by injecting TNF-α inhibiting Infliximab (open circle). PBS (closed circle), BAG (20 μg, cross), and Infliximab (1 mg, open rectangle) were injected as controls. *P <0.05 as compared with the LT-BAG group.