(A) The expression levels of TLR9 in PRMs and monocyte-derived macrophages (MDMs) in naive WT mice and mice inoculated with MC38 tumor for 3 weeks, with indicated treatments, were analyzed using flow cytometry. (B and C) Flox and FRC-Tlr9^–/– mice were treated with PBS or ODN1585 (ODN; 5 nmol/mouse, i.p.) for 18 hours. (B) The numbers and (C) percentages of GATA6⁺ PRMs were assessed using flow cytometry. (D) Mice were inoculated with MC38-luciferase-GFP (1 million cells/mouse, i.p.) and received treatments for 3 weeks, as indicated in Figure 1A. The percentage of GATA6⁺ PRMs in peritoneal lavage fluid were analyzed using flow cytometry. (E and F) Peritoneal cells were isolated from WT mice and cultured with or without control FRCs, ODN1585-preconditioned FRCs (2.5 μM, 18 hours), or LPS-preconditioned FRCs (1 μg/mL, 18 hours) for 18 hours. (E) The percentage of GATA6⁺ PRMs in F4/80⁺ macrophages and (F) mean fluorescence intensity of GATA6 were analyzed using flow cytometry. (B–D) Data are shown as mean ± SD from 2 separate experiments. (E and F) The experiments were repeated 3 times. Data are shown as mean ± SD from 1 representative experiment. Symbols represent individual mice. Statistical differences were determined using 1-way ANOVA with Tukey’s multiple comparisons test. *P < 0.05, **P < 0.01. Only the significant differences are labeled.