Inflammatory Bowel Diseases最新文献

Background: Immune cell populations in the intestinal muscularis propria during colitis are poorly resolved. Maintaining homeostasis in this niche is critical, highlighted by the poorer prognosis of inflammatory bowel disease associated with muscularis propria inflammation.

Methods: This study utilizes single-cell RNA sequencing to survey the immune cell populations within the muscularis propria of normal colon and dextran sodium sulfate-induced colitis. Findings are validated by immunohistochemistry, flow cytometry and cell-lineage tracing in vivo, and in vitro assays with muscularis macrophages (MMφ).

Results: In naïve conditions, transcriptional duality is observed in MMφs with 2 major subpopulations: conventional resident Cx3cr1+ MMφs and Lyve1+ MMφs. The Lyve1+ population is phagocytic and expresses several known MMφ markers in mouse and human, confirming their identity as a bona fide MMφ subset. Single-cell transcriptomics indicate that resident MMφs are retained during colitis and exhibit plasticity toward an inflammatory profile. Lyve1+ MMφs, which express anti-inflammatory marker CD163, are absent during colitis, as confirmed by flow cytometry. In contrast, lineage tracing finds that resident Cx3cr1+ MMφs remain during colitis and are not completely replaced by the inflammatory infiltrating monocytes. In vitro studies provide biological evidence of the plasticity of resident Cx3cr1+ MMφs in response to lipopolysaccharide (LPS), mirroring transcriptional observations in vivo of their inflammatory plasticity. Potential markers for colitic MMφs, validated in animal models and in individuals with ulcerative colitis, are identified.

Conclusions: Our findings contribute to the understanding of the immune system in the muscularis propria niche during colitis by resolving the heterogeneity and origins of colitic MMφs.

Background: Limited data are available on the outcome of inflammatory bowel disease (IBD) in patients with solid organ transplantation (SOT). We describe the natural history of pre-existing IBD and de novo IBD after SOT.

Methods: This was a retrospective, multicenter study that included patients with pre-existing IBD at the time of SOT and patients with de novo IBD after SOT. The primary outcome was IBD progression, defined by escalation of medical treatment, surgical therapy, or hospitalization due to refractory IBD. Risk factors were identified using multivariate Cox proportional hazard analysis.

Results: A total of 177 patients (106 pre-existing IBD and 71 de novo IBD) were included. Most patients with pre-existing IBD (92.5%) were in remission before SOT. During follow-up, 32% of patients with pre-existing IBD had disease progression, with a median time between SOT and IBD progression of 2.2 (interquartile range, 1.3-4.6) years. In the de novo cohort, 55% of patients had disease progression with a median time to flare of 1.9 (interquartile range, 0.8-3.9) years after diagnosis. In the pre-existing IBD cohort, active IBD at the time of SOT (hazard ratio, 1.80; 95% confidence interval, 1.14-2.84; P = .012) and the presence of extraintestinal manifestations (hazard ratio, 3.10; 95% confidence interval, 1.47-6.54; P = .003) were predictive factors for IBD progression.

Conclusions: One-third of patients with pre-existing IBD and about half of patients with de novo IBD have disease progression after SOT. Active IBD at the time of SOT and the presence of extraintestinal manifestations were identified as risk factors for IBD progression.

Background: Intestinal fibrosis, a complex complication of colitis, is characterized by excessive extracellular matrix (ECM) deposition. Estrogen receptor (ER) β may play a role in regulating this process.

Methods: Intestinal tissue samples from stenotic and nonstenotic regions were collected from Crohn's disease (CD) patients. RNA sequencing was conducted on a mouse model to identify differentially expressed mRNAs. Histological, immunohistochemical, and semiquantitative Western blotting analyses were employed to assess ECM deposition and fibrosis. The roles of relevant pathways in fibroblast transdifferentiation, activity, and migration were examined.

Results: Estrogen receptor β expression was found to be downregulated in the stenotic intestinal tissue of CD patients. Histological fibrosis score, collagen deposition, and profibrotic molecules in the colon of an intestinal fibrosis mouse model were significantly decreased after activation of ERβ. In vitro, ERβ activation alleviated transforming growth factor (TGF)-β-induced fibroblast activation and migration, as evidenced by the inhibition of col1α1, fibronectin, α-smooth muscle actin (α-SMA), collagen I, and N-cadherin expression. RNA sequencing showed that ERβ activation affected the expression of genes involved in ECM homeostasis and tissue remodeling. Enrichment analysis of differentially expressed genes highlighted that the downregulated genes were enriched in ECM-receptor interaction, TGF-β signaling, and Toll-like receptor (TLR) signaling. Western blotting confirmed the involvement of TGF-β/Smad and TLR4/MyD88/NF-κB signaling pathways in modulating fibrosis both in vivo and in vitro. The promoter activity of TGF-β1 and TLR4 could be suppressed by ERβ transcription factor.

Conclusion: Estrogen receptor β may regulate intestinal fibrosis through modulation of the TGF-β/Smad and TLR4/MyD88/NF-κB signaling pathways. Targeting ERβ activation could be a promising therapeutic strategy for treating intestinal fibrosis.

Background: A role for eosinophils in intestinal inflammation and fibrosis in the context of inflammatory bowel disease has been suggested, yet the precise nature, whether causal or secondary remains debated. Hence, it remains unclear whether targeting eosinophils should be further explored as a treatment option in inflammatory bowel disease.

Methods: Acute and chronic dextran sulfate sodium colitis was induced in wild-type C57BL/6 mice. Eosinophils were depleted by anti-CCR3 injections before colitis induction in a chronic model and after colitis onset in an acute model in order to investigate the impact of eosinophil depletion on pre-existing colitis. Inflammation was assessed using the disease activity index, macroscopic damage, and histological disease activity score. In the chronic model, fibrosis was assessed by examining colon weight/length ratio, collagen deposition through Martius Scarlet Blue staining, hydroxyproline assay, and COL1A1 expression. Protein and gene expression were assessed using the Meso Scale Discovery platform and real-time quantitative polymerase chain reaction.

Results: In the acute and chronic colitis model, eosinophil depletion resulted in reduced disease activity and faster recovery, as observed via the total area under the curve of the disease activity index (P = .004 and P = .02, respectively), macroscopic damage score (P = .009 and P = .08, respectively), and histological disease activity score (P = .09 and P = .002, respectively). In the acute model, the accelerated recovery was accompanied by an increase in interleukin (IL)-10 (P = .03) and a decrease in IL-4 (P = .03) and IL-6 (P = .009). Colon weight/length ratio and collagen deposition were not affected by eosinophil depletion.

Conclusions: Eosinophil depletion prevents and decreases intestinal inflammation in a preclinical dextran sulfate sodium model without affecting fibrosis. These results pave the way for exploring eosinophil depletion as a novel treatment modality in addressing intestinal inflammation.

Background: Crohn's disease (CD) significantly affects patients' well-being and is influenced by stress and lifestyle factors, highlighting the importance of improving quality of life in CD management. An imbalance between pro- and anti-inflammatory CD4+ T cell responses is a key factor in CD, and stress has been shown to alter the function of CD4+ T cells. Therefore, this study aimed to evaluate the effect of a mind-body medicine stress management and lifestyle modification (MBM) program on the CD4+ T cell profile in CD patients.

Methods: Circulating CD4+ T cells from CD patients were analyzed by flow cytometry following the MBM program. Patients were randomly assigned to either a guided intervention group (IG) or a self-guided waitlist control group (CG) over a 9-month trial and compared with healthy blood donors.

Results: Lifestyle intervention reduced regulatory T cell (Treg) frequencies in the blood of CD patients. Notably, we observed a significant correlation between the quality of life improvement and Treg frequencies in the IG but not in the CG. Furthermore, differential activation and expression of the gut-homing molecules G protein-coupled receptor 15 and CCR9 on circulating Tregs and CD4+ effector T cells were detected in both the IG and CG.

Conclusions: The MBM program, whether guided or self-directed, has the potential to restore the CD4+ T cell profile of CD patients to levels comparable to healthy blood donors. Lifestyle interventions may benefit CD progression, symptoms, and immunological status, but further analysis is needed to substantiate these findings and to fully understand their clinical implications. (ClinicalTrials.gov: NCT05182645).

The past 2 decades have witnessed extraordinary advances in our understanding of the genetic factors influencing inflammatory bowel disease (IBD), providing a foundation for the approaching era of genomic medicine. On behalf of the NIDDK IBD Genetics Consortium, we herein survey 11 grand challenges for the field as it embarks on the next 2 decades of research utilizing integrative genomic and systems biology approaches. These involve elucidation of the genetic architecture of IBD (how it compares across populations, the role of rare variants, and prospects of polygenic risk scores), in-depth cellular and molecular characterization (fine-mapping causal variants, cellular contributions to pathology, molecular pathways, interactions with environmental exposures, and advanced organoid models), and applications in personalized medicine (unmet medical needs, working toward molecular nosology, and precision therapeutics). We review recent advances in each of the 11 areas and pose challenges for the genetics and genomics communities of IBD researchers.

Introduction: To better inform the risk of cuffitis in patients with ulcerative colitis (UC), we aimed to identify its occurrence and associated precolectomy factors in a large multicenter cohort of patients who underwent restorative proctocolectomy (RPC) with stapled ileal pouch-anal anastomosis (IPAA).

Methods: This study was a retrospective cohort analysis of individuals diagnosed with UC or indeterminate colitis who underwent RPC with IPAA for refractory disease or dysplasia at Mount Sinai Hospital or the University of Chicago followed by at least 1 pouchoscopy with report of the pouch-anal anastomosis. The primary outcome was cuffitis defined as ulceration of the cuff as reported in each pouchoscopy report.

Results: The pouch-anal anastomosis was mentioned in the pouchoscopy reports of 674 patients, of whom 525 (77.9%) had a stapled anastomosis. Among these, cuffitis occurred in 313 (59.6%) patients a median of 1.51 (interquartile range 0.59-4.17) years after final surgical stage. On multivariable analysis, older age (hazard ratio [HR], 1.01; 95% confidence interval [CI], 1.01-1.02), extensive disease (HR, 1.34; 95% CI, 1.01-1.78), exposure to biologics before colectomy (HR, 2.51; 95% CI, 1.93-3.27), and exposure to at least 2 or more biologics before colectomy (HR, 2.18; 95% CI, 1.40-3.39) were significantly associated with subsequent cuffitis.

Conclusions: In this multicenter study of patients who underwent RPC with stapled IPAA and at least 1 follow-up pouchoscopy, cuffitis occurred in approximately 60% and was significantly associated with extensive disease and exposure to multiple biologics precolectomy.