Project description:Adhesions are fibrotic scars that form between abdominal organs following surgery or infection, and may cause bowel obstruction, chronic pain, or infertility. Adhesions occur post-operatively in 50-90% of all open abdominal operations and as such, represent an enormous clinical problem impacting hundreds of millions of patients worldwide. Our understanding of the biology of adhesion formation is very limited, which explains why there are essentially no available treatments that prevent adhesions. In this study, we systemically analyzed abdominal adhesions in mouse and human tissues gene expression using bulk- and sc-RNA-seq technologies to characterize the fibroblasts responsible for this devastating pathology.
Project description:Post-operative abdominal adhesions are the leading cause of bowel obstruction and a major cause of chronic pain and infertility. Further, adhesion formation complicates any re-operative strategy, increasing the length of surgery and rendering a safe minimally invasive approach impossible. Despite the prevalence of abdominal adhesions, which form following 50-90% of abdominal operations, no proven preventative or treatment strategy has been developed. Our group previously established a mouse model to study adhesive disease in vivo and explored adhesion biology across mouse and human tissues. We established that adhesions derive primarily from the visceral peritoneum, are composed of poly-clonally proliferating tissue-resident fibroblasts, and identified that modulation of JUN signaling regulates abdominal adhesiogenesis following surgery. We identified a small molecule JUN inhibitor (T-5224) that decreases adhesion formation. Here, we encapsulated T-5224 in a shear-thinning hydrogel with anti-adhesion properties for intra-peritoneal delivery and sustained-release for post-operative adhesion prevention. We extensively characterized this novel therapeutic system, and found it to be safe, systemically well-tolerated, and efficacious in reducing adhesions in our mouse model. Furthermore, this therapeutic system minimizes not only the quantity of adhesions that form, but also limits the maturation of adhesion fibrosis at an ultrastructural level. Critical towards clinical translation, we developed a large mammal (porcine) preclinical model of adhesions with bowel resection and showed that the T-5224-hydrogel therapeutic provides robust adhesion prevention without deleterious effects on bowel anastomosis or abdominal wall (laparotomy) wound healing. At a single-cell transcriptomic level, treated fibroblasts in our pig model show decreased JUN and associated pathway signaling. Adhesion biology shares close similarities across surgical sites (e.g. thoracic, joint space, neurological); as such, this formulation has significant potential for applicability across the body. Material properties of the T-5224-hydrogel formulation, such as shear-thinning and self-healing, also facilitate ease of open or minimally invasive application. Therefore, these results are promising for immediate and high-impact translation to patient care to address a common, unmet clinical need.
Project description:Abdominal surgeries are lifesaving procedures but can be complicated by the formation of peritoneal adhesions, intra-abdominal scars that cause intestinal obstruction, pain, infertility, and significant health costs. Despite this burden, the mechanisms underlying adhesion formation remain unclear and no cure exists. Here, we show that contamination of gut microbes increases post-surgical adhesion formation. Using genetic lineage tracing we show that adhesion myofibroblasts arose from the mesothelium. This transformation was driven by epidermal growth factor receptor (EGFR) signaling. The EGFR ligands Amphiregulin and Heparin-binding Epidermal Growth Factor, were sufficient to induce these changes. Correspondingly, EGFR inhibition led to a significant reduction of adhesion formation in mice. Adhesions isolated from human patients were enriched in EGFR positive cells of mesothelial origin and human mesothelium showed an increase of mesothelial EGFR expression during bacterial peritonitis. In conclusion, bacterial contamination drives adhesion formation through mesothelial EGFR signaling. This mechanism may represent a therapeutic target for the prevention of adhesions after intra-abdominal surgery.
Project description:Abdominal adhesions form in response to peritoneal trauma that can occur during surgery. Postoperative adhesions, which develop in approximately 50-85% of patients who have undergone abdominal surgery, often result in severe complications, including intestinal obstruction, female infertility, chronic pain, and contraindication of surgery for future abdominal illnesses such as cancer. Here, we investigated the cell source of collagen production in postoperative adhesions and explored molecular mechanisms of adhesion using microarray.
Project description:Rationale: Adhesion formation is a frequent complication after abdominal surgery. Adhesion formation might be reduced by laparoscopic surgery, however sound evidence is lacking. Colorectal surgery would be a good clinical model to investigate adhesion formation between open and laparoscopic surgery because of the adhesion formation propensity of colorectal surgery. However, a randomized controlled study to provide direct evidence is unlikely because of large numbers of patients needed for such a trial and the difficulty to check for adhesion formation at second surgery. Therefore we investigate adhesion formation after laparoscopic and open colorectal surgery for malignancy at liver surgery for metastases.
Objective: The aim of our study is to compare the incidence of adhesions after laparoscopic versus open surgery for colorectal malignancies during liver resection for colorectal metastases.
Study design: The study is designed as a prospective observational cohort study.
Study population: All consecutive, adult patients undergoing laparotomy or laparoscopy for intended liver resection or radio frequency ablation for liver metastases of a colorectal malignancy in whom inspection of the middle and lower abdomen is possible to map adhesions.
Main study parameters/endpoints:
* Primary endpoint is incidence of adhesions to the ventral abdominal wall around the site of the original incision.
* Secondary endpoints are episodes of bowel obstruction between index surgery and liver surgery; total incidence of adhesions; extent of adhesions; Zühlke classification of adhesions; performance of adhesiolysis; duration of adhesiolysis; peroperative complications: enterotomy, seromuscular injury, inadvertent organ injury during adhesiolysis; postoperative complications: delayed diagnosed perforation, SAE’s.
Nature and extent of the burden and risks associated with participation, benefit and group relatedness: This study is an observational study. The existence of adhesions will be assessed during laparotomy or laparoscopy for the treatment of liver metastases. The laparotomy is indicated for medical treatment and should not be enlarged solely for the assessment of adhesions nor will the operating time be influenced for this purpose.
Adhesions and peroperative complications have to be scored by the operating surgeon during or directly after surgery. The postoperative complications have to be scored during the postoperative course by the doctors on the ward. These assessments do not interfere with the treatment of the patients.
Project description:To further dissect whether and how activated JUN reconfigures the chromatin landscape, we performed Chromatin Immunoprecipitation (ChIP)-seq analyses for H3K4me1 and H3K27ac. Based on the significant increase of H3K27ac levels at H3K4me1+ sites, we identified 3,017 JUN-activated enhancers in JUN WT cells. In contrast, JUN AA fails to significantly induce H3K27ac accumulation at these regions. Their enrichment levels at JUN-activated enhancers were significantly decreased after JNKi treatment. Besides, these enhancers are directly driven by JUN, especially phosphorylated JUN.
Project description:Hypertrophic skin scarring following dermal injury causes extreme pain and psychological trauma for patients. Unfortuately, we do not have effective treatments to prevent or reverse skin scarring. Using RNA and ATAC sequencing of mouse and human fibroblasts, we show that JUN expressing fibroblasts are responsible for skin scarring by regulating CD36 expression. In summary, we show that CD36 antagonism by represent a therapeutic target to overcome JUN hypertrophic skin scarring.
Project description:To examine the effects of phosphorylated JUN-mediated enhancers activation on gene expression, we conducted RNA-seq analysis in JUN wildtype (WT) or JUN inactive mutant (JUN AA) overexpressed MRC5 cells. The expression levels of genes associated with JUN-activated enhancers are significantly upregulated in JUN WT cells rather than in JUN AA cells. To quantify the effects of JUN inactivation on gene expression, we also performed RNA-seq analysis in JNKi-treated induced CAFs (iCAFs). We observed that JNKi significantly reduced expression levels of JUN-activated enhancers-associated genes.