Fig. 5

α-Toxin augments Toll-like receptor (TLR)-mediated inflammatory responses. a–c C57BL/6J mice were injected intraperitoneally with 40 ng of purified α-toxin and 100 μg of lipopolysaccharide (LPS). The survival of mice was monitored, and Kaplan–Meier survival curves are shown (a). At 12 h after administration, plasma glutamic-oxaloacetic transaminase (GOT) activities (b, n = 10 per condition), interleukin (IL)-6 levels, IL-1β levels, and tumor necrosis factor (TNF)-α levels (c, n = 10 per condition) were determined. d–f C3H/HeJ mice and C3H/HeN mice were injected intraperitoneally with 40 ng of purified α-toxin and 100 μg of LPS. The survival of mice was monitored, and Kaplan–Meier survival curves are shown (d). At 12 h after the administration, plasma GOT activities (e, n = 10 per condition), IL-6 levels, IL-1β levels, and TNF-α levels (f, n = 10 per condition) were determined. g–i C57BL/6J mice (WT) and Tlr4^−/− mice (TLR4^−/−) were injected intraperitoneally with 40 ng of purified α-toxin and 100 μg of LPS. The survival of mice was monitored, and Kaplan–Meier survival curves are shown (g). At 12 h after the administration, plasma GOT activities (h, n = 5 per condition), IL-6 levels, IL-1β levels, and TNF-α levels (i, n = 5 per condition) were determined. j Mice were injected intramuscularly with 20 ng of purified α-toxin and 100 μg of peptidoglycan (PGN). At 24 h after the administration, IL-6 and IL-1β levels in the muscle were determined by enzyme-linked immunosorbent assay (n = 10 per condition). Log-lank test (a, d, g), one-way analysis of variance (b, c, j), and two-tailed Student’s t test (e, f, h, i) were employed to assess statistical significance. Values are mean ± standard error. Combined data from two independent experiments were shown