Journal: Nature Communications
Article Title: Loss of Fsr quorum sensing promotes biofilm formation and worsens outcomes in enterococcal infective endocarditis
doi: 10.1038/s41467-026-68366-8
Figure Lengend Snippet: A Z-projections of WT and Δ gelE vegetations at 72 hpi, captured with LSCM and stained for DNA, myeloperoxidase (MPO), and IL-1β. Cyan insets are highlighting the presence of IL-1β between the NETs-biofilm interface. Orange inset is shown in Fig. S4B, highlighting the colocalization of IL-1β with neutrophils. Representative images shown from n = 3, N = 1. Bf = biofilm, scale = 20 µm. B Detection and quantification of IL-1β in WT and Δ gelE vegetations at 72 hpi with western blotting. Loading control = β-actin. Mean ± SEM, n = 5 from N = 2, A.U. = arbitrary units. Statistical significance was assessed with a two-tailed t-test. C Rat pro-IL-1β and its cleaved fragments in supernatants from OG1RF WT and mutant strains detected by western blotting. Rat pro-IL-1β was incubated in BHI with indicated OG1RF strains for 2, 4, 6 h. BHI = Negative control with only media and pro-IL 1β. Representative blot shown from N = 2. D Human pro-IL-1β and its cleaved fragments in supernatants from OG1RF WT and mutant strains detected by western blotting. Human pro-IL-1β was incubated in BHI with indicated OG1RF strains for 2, 4, 6, and 24 h. Gelatinase presence was also determined in these supernatants. Δ gelE :: gelE E352A expresses proteolytically inactive gelatinase. Representative blot shown from N = 2. BHI = Negative control with only media and pro-IL 1β. E Mean activation of HEK-Blue IL-1R reporter cells by supernatants harvested from OG1RF WT and Δ gelE :: gelE E352A cultures with or without human pro-IL-1β at 18 h. Stimulation of cells with mature human IL-1β was used as a positive control. N = 3, Error = SEM. Statistical significance was determined with one-way ANOVA. F Schematic representation of gelatinase (blue) and caspase-1 cleavage sites (red) across human, rat, and mouse pro-IL-1β; n = animals per group, N = independent experiments, ns not significant (p ≥ 0.05), Red arrowhead = pro-IL-1β, blue arrowhead = mature IL-1β. Exact p values are reported in the figure. Source data are provided as a Source Data file.
Article Snippet: E. faecalis overnight cultures of OG1RF WT and mutants were diluted 1:10 in 1 mL fresh BHI supplemented with either human pro-IL-1β (100 pg/mL), or human IL-1β (100 pg/mL, Cat. Nr. ab9617, Abcam), or rat pro-IL-1β (10 ng/mL, Cat. Nr. 80023-R07E, Sino Biological), or rat IL-1β (10 ng/mL, Cat. Nr. ab281807, Abcam) and incubated for 6 h at 37 °C, static conditions.
Techniques: Staining, Western Blot, Control, Two Tailed Test, Mutagenesis, Incubation, Negative Control, Activation Assay, Positive Control