Inhibitory effect of mAb T2.5 on host activation by microbial challenge in vivo. Mice were pretreated i.p. with 1 mg mAb T2.5 (black bars) or left untreated (white bars). Mice were challenged i.p. with P3CSK4 and D-galactosamine after 1 hour and sacrificed 2 or 4 hours later (n = 4 for each group at each time point). Serum concentrations of TNF-α (A), GROα/KC (human IL-8 homolog) (B), IL-6 (C), and IL-12p40 (D) were analyzed by ELISA. *P < 0.05, **P < 0.005, ***P < 0.001, Student’s t test for unconnected samples.