Fig. 5

Neutralization ability of YG8–2 in vivo. (a) The neutralization potency of YG8–2 was determined in retroorbital challenge of mice with HlgAB. YG8–2 was serially diluted and mixed with HlgAB (10 μg/mL) at room temperature for 30 min, and the mixture (100 μL) was then injected into mice. The survival rate was measured at different time points postchallenge. Data are presented as the percentage of mice surviving. Survival curves were plotted using the Kaplan-Meier method and compared using the log-rank test (n = 6). (b–d) Determination of the effects of YG8–2 in a murine peritonitis model. Different concentrations of YG8–2 (10 or 100 μg/mouse) were injected into the peritoneal cavity of BALB/c mice 4 h prior to intraperitoneal challenge with S. aureus USA300 (0.75 × 10⁸ CFU/mouse). The survival rate was measured at different time points postchallenge (b). At 12 h postinfection, peripheral blood was plated to evaluate the bacterial burden (c). The surviving mice were sacrificed, and bacterial colonies in the kidneys were counted at 60 h postinfection (d). Data are representative of three independent experiments and shown as the mean ± SD. Significant differences between groups were evaluated using two-tailed Student’s t tests. Survival curves were determined using the Kaplan-Meier method and compared using the log-rank test (n = 14)