Fig. 4. Reduced PGE2 production downstream of inhibited TG synthesis affects inflammatory macrophage function.

a Down regulated enriched pathways in macrophages stimulated with IFNγ + LPS in the presence or absence of DGAT1i for 18 h. Assessed using RNAseq data. b Prostaglandin-E synthase activity genes expression at 18 h post stimulation with IFNγ + LPS without or with DGAT1i as measured by RNAseq. c Total pool of prostaglandin E2 (PGE2) in resting (M0) or IFNγ + LPS-stimulated macrophages, treated with or without DGAT1i for 18 h (n = 3 biologically independent samples). d TGs containing FA 20:4 (arachidonic acid) at 18 h in M0, or macrophages stimulated with IFNγ + LPS, with or without DGATi (n = 4 biologically independent samples). pro IL-1β (e) or IL-6 (f) positive macrophages (percentage cytokine-positive F4/80⁺ cells, measured by flow cytometry), 6 h after stimulation with IFNγ + LPS with or without DGATi and/or exognenous PGE2, as shown. PGE2 was added 1 h after IFNγ + LPS or IFNγ + LPS + DGATi, and cells were collected 5 h later (n = 3 for controls without γ + LPS and n = 4 for γ + LPS biologically independent samples). g Fold increases in pro IL-1β and IL-6 production (measured as percentage cytokine-positive F4/80⁺ cells) induced by exogenous PGE2 in macrophages stimulated with IFNγ + LPS in the presence or absencer of DGAT1i (γ + LPS + PGE2 n = 3, γ + LPS DGAT1i + PGE2 n = 4 biologically independent samples). h Effect of PGE2 on the ability of EV or shDgat1-transduced macrophages to phagocytose S. aureus (PE-labelled) after simulation with IFNγ + LPS. Data show percentage of F4/80⁺ cells positive for S.aureus (n = 3 biologically independent samples). Data are represented as mean values ± s.e.m. One-way ANOVA with Bonferroni’s multiple comparison test (c–f, h); Unpaired two-tailed Student’s t test (g). (*p < 0.05, **p < 0.01). (a, b, d) representative of one experiment, (c, e–h) representative of two experiments. Source data are provided as a Source Data file.