Fig. 1: Surgical injury and microbe contamination augment post-surgical peritoneal adhesions.

a C57BL/6(J) mice were surgically injured by applying two peritoneal buttons (PB) per side (left panel) in combination with or without microbial contamination through cecal ligation and puncture (CLP) (right panel). b Surgical model resulted in the formation of peritoneal adhesions within 7 days post-surgery. Adhesions were scored for tenacity and vascularization at six locations and the sum of these scores is the adhesion index. c Representative macroscopic image of an adhesion (asterisk) between small intestine and PB. Scale bar: 1 mm. d Adhesion index 7 days post-surgery after CLP, PB, and PB + CLP in SPF mice. Data representative of n = 5 for Ctrl, 5 for CLP, 5 for PB and 7 for CLP + CLP independent animals, representing 2 independent experiments. Data are presented as individual values and boxplots (median, first and third quartile). CLP vs PB: p = 0.39, CLP vs. CLP + PB: p = 0.0053, PB vs CLP + PB: p = 0.0053 e Adhesion index resulting 7 days post-surgery in germ-free (GF), gnotobiotic (stable defined moderately diverse mouse microbiota, sDMDMm2) and specific-pathogen-free (SPF) mice. All mice underwent PB + CLP surgery. Data pooled from 2 independent experiments representative of n = 15 for GF, 7 for sDMDMm2, and 9 for SPF independent animals. Data are presented as individual values and boxplots (median, first and third quartile). GF vs. sDMDMm2: p = 0.028, GF vs. SPF: p = 0.0097, sDMDMm2 vs. SPF: p = 0.63. f Collagen quantification (% adhesion area) in GF and SPF mice 7 days after surgery (PB + CLP). Data representative of 6 for GF and 8 for SPF independent animals. Data are presented as individual values and boxplots (median, 25th, and 75th percentile). Wilcoxon test (two-sided) with Holm-Bonferroni correction for multiple testing. *P < 0.05, **P < 0.01. Source data are provided as a Source Data file.