Figure 6. LPS Targets Deciduae, Not Ovaries, and Regulation of IL-10 by Stat3.

(A) Incidence of PTB in pregnant mice ovariectomized on day 16 with or without exposure to LPS (40 μg/mouse) followed by P₄ injections (1 mg) on days 16 and 17 and 250 μg of P₄ on day 18 with an additional injection of estradiol-17β (100 ng) on day 19. All ovariectomized (Ovx) mice given P₄ and E₂ without LPS showed normal delivery, albeit 40% dead pups. In contrast, over 90% of LPS-treated mice delivered dead pups before day 19 with 100% dead pups. Ovx, ovariectomy. n, number of mice examined in each group.

(B) Rate of dead pups in mice with or without LPS injection after ovariectomy followed by P₄ and E₂ injection. n = 12.

(C) Relative expression of Prlr mRNA in Tlr4^f/f and Tie2^Cre/+Tlr4^f/f mice after exposure to LPS (40 μg/mouse) for 1 hour. n = 4, *p < 0.05. Results are shown as mean ± SEM.

(D) DIG-in situ hybridization for Prlr in Tlr4^f/f mice after 6 h of LPS (40 μg/mouse) treatment. Scale bar, 500 μm.

(E and G) Graphic representation of predicted Stat3 binding site on the Il10 gene (E) and ChIP-qPCR confirmation of binding by both pStat3 and Stat3 antibodies in deciduae after LPS injection for 1 h (G). n = 3, *p < 0.05. Data are represented as mean ± SEM.

(F and H) Graphic representation of H3K4me3 enrichment at the Il10 promoter region (F) with ChIP-qPCR confirmation in deciduae after LPS injection for 1 h (H). n = 3, *p < 0.05. Data are represented as mean ± SEM.