Fig. 1
Lugdunin sensitizes epithelial cells for innate immune defense. a Primary human keratinocytes (PHKs) were pretreated with S. epidermidis conditioned medium (CM), indicated lugdunin concentrations, or the combination of both for 20 h. Subsequently, cells were infected with S. aureus for 1.5 h followed by cell lysis and determination of colony-forming units (CFUs). Shown is one representative experiment of three independent experiments with six technical replicates ± s.e.m. n.s., not significant. b Dorsal skin of mice was pretreated with S. epidermidis CM, 1.5 µg lugdunin alone or in combination with S. epidermidis CM for 24 h. Subsequently, S. aureus CFUs were determined. Horizontal lines represent the mean of each group ± s.e.m. c PHKs were treated with 2 μM lugdunin or with S. epidermidis CM alone or in combination for 20 h and subsequently expression of indicated antimicrobial peptides (AMPs) (respective protein names in brackets) was analyzed and normalized to actin. Shown is one representative experiment of three independent experiments with two technical replicates ± s.e.m. d PHKs were treated with 2 µM lugdunin or 100 ng/mL Pam2Cys for 5 h and subsequently the concentration of indicated cytokines in the supernatant was analyzed by LEGENDplexTM (BioLegend). Shown is one representative experiment of three independent experiments with two technical replicates ± s.e.m. e PHKs were treated with increasing concentrations of lugdunin or 100 ng/mL Pam2Cys or Pam3Cys for 5 h and subsequently expression of chemokine (C-X-C motif) ligand 8 (CXCL8) was analyzed and normalized to actin. Shown is one representative experiment of three independent experiments, each with two technical replicates ± s.e.m. f, g Indicated cells were treated with 2 µM lugdunin or 100 ng/mL Pam2Cys as a positive control for 5 h and subsequently the concentration of CXCL8 (f) and interleukin-1α (IL-1α) (g) in the supernatant was analyzed by LEGENDplexTM (BioLegend) and enzyme-linked immunosorbent assay (ELISA) (R&D Systems). Shown is one representative experiment of three independent experiments with two technical replicates ± s.e.m. Significant differences to control treatments were analyzed by ordinary one-way analysis of variance (ANOVA) followed by Dunnett’s multiple comparisons test (*P < 0.05; **P < 0.01; ***P < 0.001; ****P < 0.0001). n.d. = not detected. Source data are provided as a Source Data file
