Fig. 1.

MKP-1^−/− mice are hyperresponsive to endotoxic shock in vivo, associated with enhanced production of TNF-α, IL-6, and IL-10. (A) MKP-1^+/+ (solid line) and MKP-1^−/− (dotted line) mice were injected i.p. with LPS (10 mg/kg, Left, n ≥ 4; 2.5 mg/kg, Right, n ≥5), and lethality was monitored for up to 50 h. Both treatments resulted in significant differences between the two groups of mice (P < 0.005 and P < 0.001 for 10 and 2.5 mg/kg LPS challenges, respectively). (B) Serum from MKP-1^+/+ (open bars) and MKP-1^−/− (filled bars) mice was collected 3 h after 10 mg/kg LPS challenge, and cytokines were measured by Bio-plex assays or ELISA (IL-6). Data show mean ± SD for four or five mice from each group (∗, P < 0.05 determined using Student’s t test).