Low levels of PC predispose mice to LPS-induced lethality. Survival of transgenic mice stably expressing various low levels of endogenous PC following LPS challenge at 2 μg/g (A) or 10 μg/g (inset). Endogenous PC plasma concentrations are represented as percent of WT levels. Induction of TAT (B) and D-dimer (C) levels at various times after LPS (2 μg/g) administration in WT (▪) and PC−/−(PCTg785) (□) mice. Effect of LPS (2 μg/g) on the aPTT (D), PT (E), platelet count (F), and plasma fibrinogen levels (G) of WT (▪) and PC−/−(PCTg785) (□) mice. Data are shown as mean ± SEM (n = 5). Pairwise comparisons between low-PC mice and WT mice were analyzed by the Student t test. One-way ANOVA with the Newman-Keuls test was used for multiple group comparison over time. *Statistical significance with P < .05. Fibrinogen/fibrin stains in various organs from WT (H,J,L,N,P) and low-PC (I,K,M,O,Q) mice at 3 hours after LPS exposure. Heart (H, I), kidney (J, K), liver (L, M), lung (N, O) and spleen (P, Q). (H-Q) Original magnification, 200×.