Updated review on immune factors in pathogenesis of Crohn’s disease

Chronic Myelomonocytic Leukemia-Associated Immune Thrombocytopenic Purpura: A Report of a Rare Case and a Review of Literature

Chronic myelomonocytic leukemia (CMML) presents as a complex hematologic malignancy with myelodysplastic and myeloproliferative features. Our case report explores the rare coexistence of CMML with immune thrombocytopenic purpura (ITP) in a 63-year-old female patient. CMML diagnosis followed World Health Organization criteria, and the patient was classified as having high-risk myelodysplastic syndrome (MDS)-CMML stage 2. Initial treatment with subcutaneous azacytidine for CMML proved partially effective, highlighting persistent severe thrombocytopenia. Subsequent investigations revealed secondary ITP associated with Crohn's disease. Conventional ITP therapies, including high-dose steroids and intravenous immunoglobulin, showed limited efficacy. Eltrombopag, a thrombopoietin receptor agonist, was initiated, resulting in the normalization of platelet counts within six weeks. Our case emphasizes the diagnostic challenges and intricate treatment landscape of CMML-associated ITP, suggesting eltrombopag as a potential therapeutic option in refractory cases. The study contributes to the evolving understanding of the complex interplay between myeloid disorders and immune-mediated hematological conditions, calling for personalized and multidisciplinary approaches to enhance patient outcomes.

Crohn's disease as the intestinal manifestation of pan-lymphatic dysfunction: An exploratory proposal based on basic and clinical data

Crohn's disease (CD) is caused by immune, environmental, and genetic factors. It can involve the entire gastrointestinal tract, and although its prevalence is rapidly increasing its etiology remains unclear. Emerging biological and small-molecule drugs have advanced the treatment of CD; however, a considerable proportion of patients are non-responsive to all known drugs. To achieve a breakthrough in this field, innovations that could guide the further development of effective therapies are of utmost urgency. In this review, we first propose the innovative concept of pan-lymphatic dysfunction for the general distribution of lymphatic dysfunction in various diseases, and suggest that CD is the intestinal manifestation of pan-lymphatic dysfunction based on basic and clinical preliminary data. The supporting evidence is fully summarized, including the existence of lymphatic system dysfunction, recognition of the inside-out model, disorders of immune cells, changes in cell plasticity, partial overlap of the underlying mechanisms, and common gut-derived fatty and bile acid metabolism. Another benefit of this novel concept is that it proposes adopting the zebrafish model for studying intestinal diseases, especially CD, as this model is good at presenting and mimicking lymphatic dysfunction. More importantly, the ensuing focus on improving lymphatic function may lead to novel and promising therapeutic strategies for CD.

Crohn's disease and clinical management today: How it does?

Crohn's Disease (CD) is an Inflammatory Bowel Disease and is characterized by an immune-mediated nature. Its etiology results from the interaction between genetic, enviromental and microbial factors. Regarding pathophysiology, it involves high levels of interleukin (IL)-12, IL-17, and Th1 profile, along with loss of tolerance mechanisms, an increase in pro-inflammatory interleukins, beyond the possibility to affect any part of the gastrointestinal tract. Its symptoms include abdominal pain, chronic diarrhea, weight loss, anorexia, and fatigue, as well as blood in the stool or rectum. Additionally, conditions comprising musculoskeletal, cutaneous, ocular, hepatic, and hematological alterations may be associated with this scenario and extra-intestinal presentation, such as erythema nodosum, anterior uveitis, osteoporosis, and arthritis can also occur. Today, clinical history, exams as fecal calprotectin, ileocolonocopy, and capsule endoscopy can be performed in the diagnosis investigation, along with treatments to induce and maintain remission. In this sense, anti-inflammatory drugs, such as corticosteroids, immunomodulators, and biological agents, as well as surgery and non-pharmacological interventions plays a role in its therapy. The aim of this review is to bring more current evidence to clinical management of CD, as well as to briefly discuss aspects of its pathophysiology, surveillance, and associated disorders.

Creeping Fat in the Pathogenesis of Crohn's Disease: An Orchestrator or a Silent Bystander?

Although the phenomenon of hypertrophied adipose tissue surrounding inflamed bowel segments in Crohn's disease has been described since 1932, the mechanisms mediating the creeping fat formation and its role in the pathogenesis of the disease have not been fully unraveled. Recent advances demonstrating the multiple actions of adipose tissue beyond energy storage have brought creeping fat to the forefront of scientific research. In Crohn's disease, dysbiosis and transmural injury compromise the integrity of the intestinal barrier, resulting in an excessive influx of intraluminal microbiota and xenobiotics. The gut and peri-intestinal fat are in close anatomic relationship, implying a direct reciprocal immunologic relationship, whereas adipocytes are equipped with an arsenal of innate immunity sensors that respond to invading stimuli. As a result, adipocytes and their progenitor cells undergo profound immunophenotypic changes, leading to adipose tissue remodeling and eventual formation of creeping fat. Indeed, creeping fat is an immunologically active organ that synthesizes various pro- and anti-inflammatory cytokines, profibrotic mediators, and adipokines that serve as paracrine/autocrine signals and regulate immune responses. Therefore, creeping fat appears to be involved in inflammatory signaling, which explains why it has been associated with a higher severity or complicated phenotype of Crohn's disease. Interestingly, there is growing evidence for an alternative immunomodulatory function of creeping fat as a second barrier that prevents an abnormal systemic inflammatory response at the expense of an increasingly proliferating profibrotic environment. Further studies are needed to clarify how this modified adipose tissue exerts its antithetic effect during the course of Crohn's disease.

Identifying immune cell infiltration and effective diagnostic biomarkers in Crohn's disease by bioinformatics analysis

Background

Crohn's disease (CD) has an increasing incidence and prevalence worldwide. It is currently believed that both the onset and progression of the disease are closely related to immune system imbalance and the infiltration of immune cells. The aim of this study was to investigate the molecular immune mechanisms associated with CD and its fibrosis through bioinformatics analysis.

Methods

Three datasets from the Gene Expression Omnibus data base (GEO) were downloaded for data analysis and validation. Single sample gene enrichment analysis (ssGSEA) was used to evaluate the infiltration of immune cells in CD samples. Immune cell types with significant differences were identified by Wilcoxon test and Least Absolute Shrinkage and Selection Operator (LASSO) regression analysis. Differentially expressed genes (DEGs) were screened and then subjected to Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) functional correlation analysis, as well as protein-protein interaction (PPI) network analysis. The cytoHubba program and the GSE75214 dataset were used to screen for hub genes and plot Receiver operating characteristic (ROC)curves to screen for possible biomarkers of CD based on diagnostic efficacy. The hub genes of CD were correlated with five significantly different immune cells. In addition, validation was performed by real time quantitative PCR (RT-qPCR) experiments in colonic tissue of CD intestinal fibrosis rats to further identify hub genes that are more related to CD intestinal fibrosis.

Results

The DEGs were analyzed separately by 10 algorithms and narrowed down to 9 DEGs after taking the intersection. 4 hub genes were further screened by the GSE75214 validation set, namely COL1A1, CXCL10, MMP2 and FGF2. COL1A1 has the highest specificity and sensitivity for the diagnosis of CD and is considered to have the potential to diagnose CD. Five immune cells with significant differences were screened between CD and health controls (HC). Through the correlation analysis between five kinds of immune cells and four biomarkers, it was found that CXCL10 was positively correlated with activated dendritic cells, effector memory CD8+ T cells. MMP2 was positively correlated with activated dendritic cells, gamma delta T cells (γδ T) and mast cells. MMP2 and COL1A1 were significantly increased in colon tissue of CD fibrosis rats.

Conclusion

MMP2, COL1A1, CXCL10 and FGF2 can be used as hub genes for CD. Among them, COL1A1 can be used as a biomarker for the diagnosis of CD. MMP2 and CXCL10 may be involved in the development and progression of CD by regulating activated dendritic cell, effector memory CD8+ T cell, γδ T cell and mast cell. In addition, MMP2 and COL1A1 may be more closely related to CD intestinal fibrosis.

Crohn's disease and breast cancer: a literature review of the mechanisms and treatment

This is a literature review describes Crohn's disease (CD) concomitant with breast cancer and summarizes possible common pathogenic mechanisms shared by the two diseases involving the IL-17 and NF-κB signaling pathways. Inflammatory cytokines including TNF-α and Th17 cells in CD patients can induce activation of the ERK1/2, NF-κB and Bcl-2 pathways. Hub genes are involved in the generation of cancer stem cells (CSCs) and are related to inflammatory mediators, including CXCL8, IL1-β and PTGS2, which promote inflammation and breast cancer growth, metastasis, and development. CD activity is highly associated with altered intestinal microbiota processes, including secretion of complex glucose polysaccharides by Ruminococcus gnavus colonies; furthermore, γ-proteobacteria and Clostridium are associated with CD recurrence and active CD, while Ruminococcaceae, Faecococcus and Vibrio desulfuris are associated with CD remission. Intestinal microbiota disorder promotes breast cancer occurrence and development. Bacteroides fragilis can produce toxins that induce breast epithelial hyperplasia and breast cancer growth and metastasis. Gut microbiota regulation can also improve chemotherapy and immunotherapy efficacy in breast cancer treatment. Intestinal inflammation can affects the brain through the brain-gut axis, which activates the hypothalamic‒pituitary‒adrenal (HPA) axis to induce anxiety and depression in patients; these effects can inhibit the antitumor immune responses of the immune system and promote breast cancer occurrence in patients with CD. There are few studies on the treatment of patients with CD concomitant with breast cancer, but published studies show three main strategies: new biological agents combined with breast cancer treatment methods, intestinal fecal bacteria transplantation, and dietary treatment.

Infliximab trough levels are associated with endoscopic healing but not with transmural healing at one year treatment with infliximab in pediatric patients with Crohn's disease

Introduction

It is well known that infliximab (IFX) trough levels (TLs) are associated with endoscopic healing (EH) in Crohn's disease (CD). We investigated whether IFX TLs are associated with transmural healing (TH) in pediatric patients with CD following 1-year treatment.

Methods

Pediatric patients with CD treated with IFX were included in this single-center prospective study. IFX TL tests, magnetic resonance enterography (MRE), and colonoscopies were simultaneously conducted after 1-year IFX treatment. TH was defined as a wall thickness of ≤3 mm without inflammatory signs evaluated using MRE. EH was defined as a Simple Endoscopic Score for Crohn's disease of <3 points on colonoscopy.

Results

Fifty-six patients were included. EH and TH were observed in 60.7% (34/56) and 23.2% (13/56) of patients, respectively. IFX TLs were higher in patients with EH (median, 5.6 vs. 3.4 µg/mL, P = 0.002), whereas IFX TLs showed no significant difference in patients with and without TH (median, 5.4 vs. 4.7 µg/mL, P = 0.574). No significant difference was observed in EH and TH between patients whose intervals were shortened or not. Multivariate logistic regression analysis showed that IFX TLs and disease duration to IFX initiation were associated with EH (odds ratio [OR] = 1.82, P = 0.001, and OR = 0.43, P = 0.02, respectively).

Discussion

In pediatric patients with CD, IFX TLs were associated with EH but not with TH. Further studies investigating long-term TH and proactive dosing based on therapeutic drug monitoring may clarify whether an association between IFX TLs and TH exists.

Fourier-transform infrared spectroscopy: a universal optical sensing technique with auspicious application prospects in the diagnosis and management of autoimmune diseases

Autoimmune diseases (AIDs) are poorly understood clinical syndromes due to breakdown of immune tolerance towards specific types of self-antigens. They are generally associated with an inflammatory response mediated by lymphocytes T, autoantibodies or both. Ultimately, chronic inflammation culminates in tissue damages and clinical manifestations. AIDs affect 5% of the world population, and they represent the main cause of fatality in young to middle-aged females. In addition, the chronic nature of AIDs has a devastating impact on the patient's quality of life. It also places a heavy burden on the health care system. Establishing a rapid and accurate diagnosis is considered vital for an ideal medical management of these autoimmune disorders. However, for some AIDs, this task might be challenging. Vibrational spectroscopies, and more particularly Fourier-transform infrared (FTIR) spectroscopy, have emerged as universal analytical techniques with promising applications in the diagnosis of various types of malignancies and metabolic and infectious diseases. The high sensitivity of these optical sensing techniques and their minimal requirements for test reagents qualify them to be ideal analytical techniques. The aim of the current review is to explore the potential applications of FTIR spectroscopy in the diagnosis and management of most common AIDs. It also aims to demonstrate how this technique has contributed to deciphering the biochemical and physiopathological aspects of these chronic inflammatory diseases. The advantages that can be offered by this optical sensing technique over the traditional and gold standard methods used in the diagnosis of these autoimmune disorders have also been extensively discussed.

Prognostic factors for the efficacy of infliximab in patients with luminal fistulizing Crohn's disease

BACKGROUND

Enteric fistula is one of the penetrating features in Crohn's disease (CD). This study aimed to clarify the prognostic factors for the efficacy of infliximab (IFX) treatment in luminal fistulizing CD patients.

METHODS

We retrospectively included 26 cases diagnosed with luminal fistulizing CD hospitalized in our medical center from 2013 to 2021. The primary outcome of our research was defined as death from all causes and undergoing of any relevant abdominal surgery. Kaplan-Meier survival curves were used to describe overall survival. Univariate and multivariate analyses were used to identify prognostic factors. A predictive model was constructed using Cox proportional hazard model.

RESULTS

The median follow-up time was 17.5 months (range 6-124 months). The 1- and 2-year surgery-free survival rates were 68.1% and 63.2%, respectively. In the univariate analysis, the efficacy of IFX treatment at 6 months after initiation (P < 0.001, HR 0.23, 95% CI 0.01-0.72) and the existence of complex fistula (P = 0.047, HR 4.11, 95% CI 1.01-16.71) was found significantly related to the overall surgery-free survival, while disease activity at baseline (P = 0.099) also showed predictive potential. The multivariate analysis showed that efficacy at 6 months (P = 0.010) was an independent prognostic factor. The C-index of the model for surgery-free survival was 0.923 (P < 0.001), indicating an acceptable predictive effect.

CONCLUSION

Prognostic model including the existence of complex fistula, disease activity at baseline and efficacy of IFX at 6 months may be useful to predict long-term outcome of luminal fistulizing CD patients.

Biphasic dose response in the anti-inflammation experiment of PBM

Non-invasive laser irradiation can induce photobiomodulation (PBM) effects in cells and tissues, which can help reduce inflammation and pain in several clinical scenarios. The purpose of this study is to review the current literature to verify whether PBM can produce dose effects in anti-inflammatory experiments by summarizing the clinical and experimental effects of different laser parameters of several diseases. The so-called Arndt-Schulz curve is often used to describe two-phase dose reactions, assuming small doses of therapeutic stimulation, medium doses of inhibition, and large doses of killing. In the past decade, more and more attention has been paid to the clinical application of PBM, especially in the field of anti-inflammation, because it represents a non-invasive strategy with few contraindications. Although there are different types of lasers available, their use is adjusted by different parameters. In general, the parameters involved are wavelength, energy density, power output, and radiation time. However, due to the biphasic effect, the scientific and medical communities remain puzzled by the ways in which the application of PBM must be modified depending on its clinical application. This article will discuss these parameter adjustments and will then also briefly introduce two controversial theories of the molecular and cellular mechanisms of PBM. A better understanding of the extent of dualistic dose response in low-intensity laser therapy is necessary to optimize clinical treatment. It also allows us to explore the most dependable mechanism for PBM use and, ultimately, standardize treatment for patients with various diseases.

Mass cytometry and single-cell RNA sequencing reveal immune cell characteristics of active and inactive phases of Crohn's disease

Objectives

For Crohn's disease (CD), the alternation of the active phase and inactive phase may be related to humoral immunity and cellular immunity. This study aims to understand the characteristics of immune cells in patients with active CD (CDa) and inactive CD (CDin).

Methods

Mass cytometry (CyTOF) and single-cell RNA sequencing (scRNA-seq) data about CDa, CDin, and healthy control (HC) were included. CyTOF analysis was performed to capture gated subsets, including T cells, T regulatory (Treg) cells, B cells, innate immune cells, and natural killer (NK) cells. Differential analysis was used to identify different immune cell subsets among CDa, CDin, and HC. ScRNA-seq analysis was used to verify the results of CyTOF. CD-related signaling pathways were obtained using KEGG pathway enrichment analysis. CellChat analysis was used to infer the cell communication network among immune cell subsets.

Results

Compared to patients with CDin, patients with CDa had higher abundances of CD16⁺CD38⁺CD4⁺CXCR3⁺CCR6⁺ naive T cells, HLA-DR⁺CD38⁺IFNγ⁺TNF⁺ effector memory (EM) T cells, HLA-DR⁺IFNγ⁺ naive B cells, and CD14⁺⁺CD11C⁺IFNγ⁺IL1B⁺ monocytes. KEGG analysis showed the similarity of pathway enrichment for the earlier four subsets, such as thermogenesis, oxidative phosphorylation, and metabolic pathways. The patients with CDin were characterized by an increased number of CD16⁺CD56^dimCD44⁺HLA-DR⁺IL22⁺ NK cells. Compared to HC, patients with CDa demonstrated a low abundance of HLA-DR⁺CCR6⁺ NK cells and a high abundance of FOXP3⁺CD44⁺ EM Tregs. CellChat analysis revealed the interaction network of cell subsets amplifying in CDa compared with CDin.

Conclusion

Some immune subsets cells were identified for CDa and CDin. These cells may be related to the occurrence and development of CD and may provide assistance in disease diagnosis and treatment.

Vagus Nerve Stimulation: A Personalized Therapeutic Approach for Crohn's and Other Inflammatory Bowel Diseases

Inflammatory bowel diseases, including Crohn's disease and ulcerative colitis, are incurable autoimmune diseases characterized by chronic inflammation of the gastrointestinal tract. There is increasing evidence that inappropriate interaction between the enteric nervous system and central nervous system and/or low activity of the vagus nerve, which connects the enteric and central nervous systems, could play a crucial role in their pathogenesis. Therefore, it has been suggested that appropriate neuroprosthetic stimulation of the vagus nerve could lead to the modulation of the inflammation of the gastrointestinal tract and consequent long-term control of these autoimmune diseases. In the present paper, we provide a comprehensive overview of (1) the cellular and molecular bases of the immune system, (2) the way central and enteric nervous systems interact and contribute to the immune responses, (3) the pathogenesis of the inflammatory bowel disease, and (4) the therapeutic use of vagus nerve stimulation, and in particular, the transcutaneous stimulation of the auricular branch of the vagus nerve. Then, we expose the working hypotheses for the modulation of the molecular processes that are responsible for intestinal inflammation in autoimmune diseases and the way we could develop personalized neuroprosthetic therapeutic devices and procedures in favor of the patients.

Creeping fat formation and interaction with intestinal disease in Crohn's disease

Creeping fat (CrF), also known as fat wrapping, is a significant disease characteristic of Crohn's disease (CD). The transmural inflammation impairs intestinal integrity and facilitates bacteria translocation, aggravating immune response. CrF is a rich source of pro-inflammatory and pro-fibrotic cytokines with complex immune microenvironment. The inflamed and stricturing intestine is often wrapped by CrF, and CrF is associated with greater severity of CD. The large amount of innate and adaptive immune cells as well as adipocytes in CrF promote fibrosis in the affected intestine by secreting large amount of pro-fibrotic cytokines, adipokines, growth factors and fatty acids. CrF is a potential therapeutic target for CD treatment and a promising bio-marker for predicting response to drug therapy. This review aims to summarize and update the clinical manifestation and application of CrF and the underlying molecular mechanism involved in the pathogenesis of intestinal inflammation and fibrosis in CD.

Construction of a neural network diagnostic model and investigation of immune infiltration characteristics for Crohn’s disease

Objective: Crohn’s disease (CD), a chronic recurrent illness, is a type of inflammatory bowel disease whose incidence and prevalence rates are gradually increasing. However, there is no universally accepted criterion for CD diagnosis. The aim of this study was to create a diagnostic prediction model for CD and identify immune cell infiltration features in CD.

Methods: In this study, gene expression microarray datasets were obtained from the Gene Expression Omnibus (GEO) database. Then, we identified differentially expressed genes (DEGs) between 178 CD and 38 control cases. Enrichment analysis of DEGs was also performed to explore the biological role of DEGs. Moreover, the “randomForest” package was applied to select core genes that were used to create a neural network model. Finally, in the training cohort, we used CIBERSORT to evaluate the immune landscape between the CD and normal groups.

Results: The results of enrichment analysis revealed that these DEGs may be involved in biological processes associated with immunity and inflammatory responses. Moreover, the top 3 hub genes in the protein-protein interaction network were IL-1β, CCL2, and CXCR2. The diagnostic model allowed significant discrimination with an area under the ROC curve of 0.984 [95% confidence interval: 0.971–0.993]. A validation cohort (GSE36807) was utilized to ensure the reliability and applicability of the model. In addition, the immune infiltration analysis indicated nine different immune cell types were significantly different between the CD and healthy control groups.

Conclusion: In summary, this study offers a novel insight into the diagnosis of CD and provides potential biomarkers for the precise treatment of CD.

Identification of healthspan-promoting genes in Caenorhabditis elegans based on a human GWAS study

To find drivers of healthy ageing, a genome-wide association study (GWAS) was performed in healthy and unhealthy older individuals. Healthy individuals were defined as free from cardiovascular disease, stroke, heart failure, major adverse cardiovascular event, diabetes, dementia, cancer, chronic obstructive pulmonary disease (COPD), asthma, rheumatism, Crohn’s disease, malabsorption or kidney disease. Six single nucleotide polymorphisms (SNPs) with unknown function associated with ten human genes were identified as candidate healthspan markers. Thirteen homologous or closely related genes were selected in the model organism C. elegans for evaluating healthspan after targeted RNAi-mediated knockdown using pathogen resistance, muscle integrity, chemotaxis index and the activity of known longevity and stress response pathways as healthspan reporters. In addition, lifespan was monitored in the RNAi-treated nematodes. RNAi knockdown of yap-1, wwp-1, paxt-1 and several acdh genes resulted in heterogeneous phenotypes regarding muscle integrity, pathogen resistance, chemotactic behaviour, and lifespan. Based on these observations, we hypothesize that their human homologues WWC2, CDKN2AIP and ACADS may play a role in health maintenance in the elderly.

Efficacy of Ustekinumab in Crohn's Disease With and Without Concurrent Autoimmune Skin Disease

BACKGROUND

Approximately 33% of Crohn's disease (CD) patients have associated autoimmune skin disease. The pathophysiology of the latter frequently involves interleukin-12/interleukin-23 signaling pathways that may also impact gut inflammation. Ustekinumab is an anti-IL-12/23 FDA-approved biologic for psoriasis and inflammatory bowel disease. However, its relative efficacy has never been studied in CD with autoimmune skin disease (CD-ASD) vs CD without autoimmune skin disease (CD-none).

METHODS

This is a retrospective, single-center, case-control study comparing markers of disease activity between CD-ASD and CD-none. Biomarkers (fecal calprotectin [FCP], C-reactive protein [CRP]) prior to drug initiation and after at least 5 months of standard IBD dose ustekinumab therapy were extracted from the medical record. In addition, 2 blinded observers performed 5-point Likert scoring before and after endoscopic, pathologic, and imaging reports.

RESULTS

In all, 395 CD patients received ustekinumab therapy (79 CD-ASD, 316 CD-none). Patients were similar in age; gender; ethnicity; CD severity, phenotype, and duration; tobacco, immunomodulator, and steroid use. Ustekinumab had greater efficacy in CD-ASD when evaluated by FCP (P = .0337) and CRP (P = .078). The CD-ASD group also showed better outcomes in Likert scores of endoscopy (P = .016), histopathology (P = .074), and imaging (P = .094). In all Likert parameters, CD-ASD had more patients with complete resolution of moderate/severe disease (P < .05). Additional subanalyses for surgeries, ulcers, abscesses, fistulas, and colitis were conducted, with colitis reaching statistical significance (P = .0011).

CONCLUSIONS

Concurrent autoimmune skin disease in CD is associated with greater ustekinumab effectiveness in controlling intestinal inflammation.

Network Pharmacology-Based Strategy to Identify the Pharmacological Mechanisms of Pulsatilla Decoction against Crohn's Disease

Purpose: To explore pharmacological mechanisms of Pulsatilla decoction (PD) against Crohn's disease (CD) via network pharmacology analysis followed by experimental validation. Methods: Public databases were searched to identify bioactive compounds and related targets of PD as well as related genes in patients with CD. Analyses using the drug-compound-target-disease network, the protein-protein interaction (PPI) network, and Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) enrichment analyses were performed to predict the core targets and pathways of PD against CD. Colon tissue resected from patients with CD and tissue samples from a mouse model of CD fibrosis treated with PD were assessed to verify the major targets of PD in CD predicted by network pharmacologic analysis. Results: A search of the targets of bioactive compounds in PD and targets in CD identified 134 intersection targets. The target HSP90AA1, which was common to the drug-compound-target-disease and PPI networks, was used to simulate molecular docking with the corresponding bioactive compound. GO and KEGG enrichment analyses showed that multiple targets in the antifibrotic pathway were enriched and could be experimentally validated in CD patients and in a mouse model of CD fibrosis. Assays of colon tissues from CD patients showed that intestinal fibrosis was greater in stenoses than in nonstenoses, with upregulation of p-AKT, AKT, p-mTOR, mTOR, p-ERK1/2, ERK1/2, p-PKC, and PKC targets. Treatment of CD fibrosis mice with PD reduced the degree of fibrosis, with downregulation of the p-AKT, AKT, p-mTOR, mTOR, p-ERK1/2, ERK1/2, and PKC targets. Conclusion: Network pharmacology analysis was able to predict bioactive compounds in PD and their potential targets in CD. Several of these targets were validated experimentally, providing insight into the pharmacological mechanisms underlying the biological activities of PD in patients with CD.

LINC01272 activates epithelial-mesenchymal transition through miR-153-5p in Crohn's disease

OBJECTIVES

Long noncoding RNAs (lncRNAs) have different functions in different diseases. There is little research on the functions of lncRNAs in Crohn's disease (CD). By using RNA-seq technology, we identified a lncRNA associated with Crohn's disease. However, the mechanism of lncRNA regulation remains unknown. This study aimed to determine the association of LINC01272 with epithelial cell-mesenchymal transition and the underlying mechanism in CD.

METHODS

RNA was detected by qRT-PCR. The interaction of protein and RNA was determined by RNA binding protein immunoprecipitation. Luciferase reporter assays were used to detect the targeted miRNA of LINC01272. Tissue fibrosis was observed by Masson and H&E staining. Protein expression was determined by western blotting and immunofluorescence.

RESULTS

LINC01272 was highly expressed in patients with CD. Knockdown of LINC01272 inhibited TGF-β1-induced epithelial-mesenchymal transition (EMT). Additionally, LINC01272 regulated TGF-β1-induced EMT through the miR-153-5p axis, and knockdown of LINC01272 inhibited EMT in CD mice in vivo.

CONCLUSION

LINC01272 activated the epithelial-mesenchymal transition through miR-153-5p in CD.

A systematic review and functional bioinformatics analysis of genes associated with Crohn's disease identify more than 120 related genes

BACKGROUND

Crohn's disease is one of the two categories of inflammatory bowel diseases that affect the gastrointestinal tract. The heritability estimate has been reported to be 0.75. Several genes linked to Crohn's disease risk have been identified using a plethora of strategies such as linkage-based studies, candidate gene association studies, and lately through genome-wide association studies (GWAS). Nevertheless, to our knowledge, a compendium of all the genes that have been associated with CD is lacking.

METHODS

We conducted functional analyses of a gene set generated from a systematic review where genes potentially related to CD found in the literature were analyzed and classified depending on the genetic evidence reported and putative biological function. For this, we retrieved and analyzed 2496 abstracts comprising 1067 human genes plus 22 publications regarding 133 genes from GWAS Catalog. Then, each gene was curated and categorized according to the type of evidence associated with Crohn's disease.

RESULTS

We identified 126 genes associated with Crohn's disease risk by specific experiments. Additionally, 71 genes were recognized associated through GWAS alone, 18 to treatment response, 41 to disease complications, and 81 to related diseases. Bioinformatic analysis of the 126 genes supports their importance in Crohn's disease and highlights genes associated with specific aspects such as symptoms, drugs, and comorbidities. Importantly, most genes were not included in commercial genetic panels suggesting that Crohn's disease is genetically underdiagnosed.

CONCLUSIONS

We identified a total of 126 genes from PubMed and 71 from GWAS that showed evidence of association to diagnosis, 18 to treatment response, and 41 to disease complications in Crohn's disease. This prioritized gene catalog can be explored at http://victortrevino.bioinformatics.mx/CrohnDisease .

The Complex Relationship Between Microbiota, Immune Response and Creeping Fat in Crohn's Disease

In the last decade, there has been growing interest in the pathological involvement of hypertrophic mesenteric fat attached to the serosa of the inflamed intestinal segments involved in Crohn's disease [CD], known as creeping fat. In spite of its protective nature, creeping fat harbours an aberrant inflammatory activity which, in an already inflamed intestine, may explain why creeping fat is associated with a greater severity of CD. The transmural inflammation of CD facilitates the interaction of mesenteric fat with translocated intestinal microorganisms, contributing to activation of the immune response. This may be not the only way in which microorganisms alter the homeostasis of this fatty tissue: intestinal dysbiosis may also impair xenobiotic metabolism. All these CD-related alterations have a functional impact on nuclear receptors such as the farnesoid X receptor or the peroxisome proliferator-activated receptor γ, which are implicated in regulation of the immune response, adipogenesis and the maintenance of barrier function, as well as on creeping fat production of inflammatory-associated cells such as adipokines. The dysfunction of creeping fat worsens the inflammatory course of CD and may favour intestinal fibrosis and fistulizing complications. However, our current knowledge of the pathophysiology and pathogenic role of creeping fat is controversial and a better understanding might provide new therapeutic targets for CD. Here we aim to review and update the key cellular and molecular alterations involved in this inflammatory process that link the pathological components of CD with the development of creeping fat.

Palmitoylation in Crohn’s disease: Current status and future directions

S-palmitoylation is one of the most common post-translational modifications in nature; however, its importance has been overlooked for decades. Crohn’s disease (CD), a subtype of inflammatory bowel disease (IBD), is an autoimmune disease characterized by chronic inflammation involving the entire gastrointestinal tract. Bowel damage and subsequent disabilities caused by CD are a growing global health issue. Well-acknowledged risk factors for CD include genetic susceptibility, environmental factors, such as a westernized lifestyle, and altered gut microbiota. However, the pathophysiological mechanisms of this disorder are not yet comprehensively understood. With the rapidly increasing global prevalence of CD and the evident role of S-palmitoylation in CD, as recently reported, there is a need to investigate the relationship between CD and S-palmitoylation. In this review, we summarize the concept, detection, and function of S-palmitoylation as well as its potential effects on CD, and provide novel insights into the pathogenesis and treatment of CD.

Melatonin reduces inflammation in intestinal cells, organoids and intestinal explants

Inflammatory bowel diseases (IBDs) are chronic and recurrent diseases that often occur in young people and place a heavy burden on public health in both developed and developing countries. Melatonin has been confirmed to be useful in various diseases, including Alzheimer's disease, liver injuries and diseases, and cancers, while its role in IBDs remains unclear. To uncover the function of melatonin in IBDs, three intestinal models, including Caco-2 cells, 3D intestinal organoids and intestinal explants, were used. It was found that different concentrations of melatonin could significantly inhibit the expression levels of NFκB and its downstream cytokines, including IL6 and IL8 in Caco-2 cells (*P < 0.05, **P < 0.01), 3D intestinal organoids (*P < 0.05, **P < 0.01) and intestinal explants (*P < 0.05, **P < 0.01). Melatonin abolished the activation of LPS on the expression levels of NFκB, IL6, and IL8 in three intestinal models (*P < 0.05, **P < 0.01, ***P < 0.001). Importantly, the roles of melatonin in the regulation of inflammation was dependent on its receptor (i.e., MTNR1), since it was found that silencing of the melatonin receptor (MTNR1A) abolished the reduction in inflammation induced by melatonin in Caco-2 cells (***P < 0.001) and 3D intestinal organoids (***P < 0.01, ****P < 0.0001). Herein, the findings in this study might provide useful information for understanding the pathogenesis of IBDs and developing novel drugs to treat the diseases.

Viral infections in inflammatory bowel disease: Tips and tricks for correct management

Over the past decades, the treatment of inflammatory bowel diseases (IBD) has become more targeted, anticipating the use of immune-modifying therapies at an earlier stage. This top-down approach has been correlated with favorable short and long-term outcomes, but it has also brought with it concerns regarding potential infectious complications. This large IBD population treated with immune-modifying therapies, especially if combined, has an increased risk of severe infections, including opportunistic infections that are sustained by viral, bacterial, parasitic, and fungal agents. Viral infections have emerged as a focal safety concern in patients with IBD, representing a challenge for the clinician: they are often difficult to diagnose and are associated with significant morbidity and mortality. The first step is to improve effective preventive strategies, such as applying vaccination protocols, adopt adequate prophylaxis and educate patients about potential risk factors. Since viral infections in immunosuppressed patients may present atypical signs and symptoms, the challenges for the gastroenterologist are to suspect, recognize and diagnose such complications. Appropriate treatment of common viral infections allows us to minimize their impact on disease outcomes and patients’ lives. This practical review supports this standard of care to improve knowledge in this subject area.

Early Ileocecal Resection Is an Effective Therapy in Isolated Crohn's Disease

Despite the increasing incidence and prevalence of Crohn’s Disease (CD), no curative options exist and treatment remains complex. While therapy has mainly focused on medical approaches in the past, growing evidence reveals that in cases of limited inflammation, surgery can suffice as an alternative primary treatment. We retrospectively assessed the disease course and outcomes of 103 patients with terminal Ileitis who underwent primary surgery (n = 29) or received primary medical treatment followed by surgery (n = 74). Primary endpoint was the need for immunosuppressive medication after surgical treatment (ileocecal resection, ICR) during a two-years follow-up. Rates for laparoscopic ICR were enhanced in case of early surgery, but no differences were seen for postoperative complications. In case of immunosuppressive medication, patients with ICR at an early state of disease needed significantly less anti-inflammatory medication during the two-year postoperative follow-up compared to patients who were primarily treated medically. Furthermore, in a subgroup analysis for patients with localized ileocecal disease manifestation, early surgery consistently resulted in a decreased amount of medical therapy postoperatively. In conclusion primary ICR is safe and effective in patients with limited CD, and the need for immunosuppressive medication during the postoperative follow-up is low compared to patients receiving surgery at a later stage of disease.

Colon tissue-accumulating mesoporous carbon nanoparticles loaded with Musca domestica cecropin for ulcerative colitis therapy

Ulcerative colitis (UC) is a modern refractory disease with steadily increasing incidence worldwide that urgently requires effective and safe therapies. Therapeutic peptides delivered using nanocarriers have shown promising developments for the treatment of UC. We developed a novel colon-accumulating oral drug delivery nanoplatform consisting of Musca domestica cecropin (MDC) and mesoporous carbon nanoparticles (MCNs) and investigated its effects and mechanism of action for the treatment of UC. Methods: An optimized one-step soft templating method was developed to synthesize MCNs, into which MDC was loaded to fabricate MDC@MCNs. MCNs and MDC@MCNs were characterized by BET, XRD, and TEM. MDC and MDC@MCNs resistance to trypsin degradation was measured through Oxford cup antibacterial experiments using Salmonella typhimurium as the indicator. Uptake of MDC and MDC@MCNs by NCM460 cells was observed by fluorescence microscopy. The biocompatibility of MDC, MCNs, and MDC@MCNs was evaluated in three cell lines (NCM460, L02, and NIH3T3) and C57BL/6 mice. Dextran sulphate sodium was used to establish models of NCM460 cell injury and UC in mice. MTT assay, flow cytometry, and mitochondrial membrane potential assay were applied to determine the effects of MDC@MCNs on NCM460 cells injury. Additionally, a variety of biological methods such as H&E staining, TEM, ELISA, qPCR, Western blotting, and 16s rDNA sequencing were performed to explore the effects and underlying mechanism of MDC@MCN on UC in vivo. Colonic adhesion of MCNs was compared in normal and UC mice. The oral biodistributions of MDC and MDC@MCNs in the gastrointestinal tract of mice were also determined. Results: MDC@MCNs were successfully developed and exhibited excellent ability to resist destruction by trypsin and were taken up by NCM460 cells more readily than MDC. In vitro studies showed that MDC@MCNs better inhibited DSS-induced NCM460 cells damage with lower toxicity to L02 and NIH3T3 cells compared with MDC. In vivo results indicated that MDC@MCNs have good biocompatibility and significantly improved colonic injury in UC mice by effectively inhibiting inflammation and oxidative stress, maintaining colonic tight junctions, and regulating intestinal flora. Moreover, MDC@MCNs were strongly retained in the intestines, which was attributed to intestinal adhesion and aggregation of MCNs, serving as one of the important reasons for its enhanced efficacy after oral administration compared with MDC. Conclusion: MDC@MCNs alleviated DSS-induced UC by ameliorating colonic epithelial cells damage, inhibiting inflammation and oxidative stress, enhancing colonic tight junctions, and regulating intestinal flora. This colon-accumulating oral drug delivery nanoplatform may provide a novel and precise therapeutic strategy for UC.

Whole Transcription Profile of Responders to Anti-TNF Drugs in Pediatric Inflammatory Bowel Disease

Background: Up to 30% of patients with pediatric inflammatory bowel disease (IBD) do not respond to anti-Tumor Necrosis Factor (anti-TNF) therapy. The aim of this study was to identify pharmacogenomic markers that predict early response to anti-TNF drugs in pediatric patients with IBD. Methods: An observational, longitudinal, prospective cohort study was conducted. The study population comprised 38 patients with IBD aged < 18 years who started treatment with infliximab or adalimumab (29 responders and nine non-responders). Whole gene expression profiles from total RNA isolated from whole blood samples of six responders and six non-responders taken before administration of the biologic and after two weeks of therapy were analyzed using next-generation RNA sequencing. The expression of six selected genes was measured for purposes of validation in all of the 38 patients recruited using qPCR. Results: Genes were differentially expressed in non-responders and responders (32 before initiation of treatment and 44 after two weeks, Log2FC (Fold change) >0.6 or <−0.6 and p value < 0.05). After validation, FCGR1A, FCGR1B, and GBP1 were overexpressed in non-responders two weeks after initiation of anti-TNF treatment (Log2FC 1.05, 1.21, and 1.08, respectively, p value < 0.05). Conclusion: Expression of the FCGR1A, FCGR1B, and GBP1 genes is a pharmacogenomic biomarker of early response to anti-TNF agents in pediatric IBD.

The Role of Active Inflammation and Surgical Therapy in Crohn's Disease Recurrence

An altered balance between effector and regulatory factors is supposed to sustain the tissue-damaging immune response in inflammatory bowel disease (IBD). Several studies demonstrate that severe active inflammation is a strong predictor for surgical complications and recurrence. Indeed, bowel resection in Crohn's disease (CD) patients has a high surgical recurrence rate. In this review, we examined the IBD inflammatory pathways, the current surgical treatments, and the almost inevitable recurrence. The question that might arise is if the cure of intestinal CD is to be found in the surgical approach. A selective search of two databases (PubMed and the Cochrane Library) has been carried out without considering a specific time horizon as inclusion criteria. The scope of this literature review was investigating on the role of inflammation in the management of CD. The following key words have been used to develop the query string: (i) inflammation; (ii) Crohn's disease; (iii) surgery; and (iv) postsurgical recurrence.

Disease progression-associated alterations in fecal metabolites in SAMP1/YitFc mice, a Crohn's disease model

Crohn's disease (CD) is a chronic, relapsing inflammatory bowel disease affecting the gastrointestinal tract. Although its precise etiology has not been fully elucidated, an imbalance of the intestinal microbiota has been known to play a role in CD. Fecal metabolites derived from microbiota may be related to the onset and progression of CD OBJECTIVES: This study aimed to clarify the transition of gut microbiota and fecal metabolites associated with disease progression using SAMP1/YitFc mice, a model of spontaneous CD METHODS: The ileum tissues isolated from SAMP1/YitFc mice at different ages were stained with hematoxylin-eosin for histologic characterization with CD progression. Feces from control, Institute of Cancer Research (ICR; n = 6), and SAMP1/YitFc (n = 8) mice at different ages were subjected to microbial analysis and ¹H nuclear magnetic resonance (NMR) analysis to investigate fluctuations in gut microbiota and fecal metabolites with CD progression RESULTS: Relative abundance of the Lachnospiraceae, Ruminococcaceae, Bacteroidaceae, and Bacteroidales S24-7 at family-level gut microbiota and fecal metabolites, such as short-chain fatty acids, lactate, glucose, xylose, and choline, dramatically fluctuated with histologic progression of intestinal inflammation in SAMP1/YitFc mice. Unlike the other metabolites, fecal taurine concentration in SAMP1/YitFc mice was higher than ICR mice regardless of age CONCLUSION: The fecal metabolites showing characteristic fluctuations may help to understand the inflammatory mechanism associated with CD, and might be utilized as potential biomarkers in predicting CD pathology.

Synchronous colonic adenoma and intestinal marginal zone B-cell lymphoma associated with Crohn's disease: a case report and literature review

Background

Lymphoma and dysplasia are rare complications of long-standing Crohn’s disease. We report an exceptional case of a synchronous intestinal marginal zone B-cell lymphoma (MALT lymphoma) and colonic adenoma in a Crohn’s disease patient.

Case presentation

A 50-year-old male patient presented with right lower quadrant for the last 9 months. He also had associated weight loss and diarrhea alternating with constipation. Ileo-colonoscopy revealed a pseudopolypoid appearance of the colonic and ileal mucosa with many discontinuous ulcerations with a 3 cm sessile polypoid mass at 17 cm from the anal verge. Histological examination of the polypoid lesion revealed an adenoma with high grade dysplasia, while the biopsies of colonic mucosa showed histologic features of Crohn’s disease. Abdominal computed tomography scan (CT scan) and magnetic resonance imaging (MRI) showed circumferential wall thickening of the colon and ileum, enlarged mesenteric lymph nodes and a sessile polypoid mass of the rectosigmoid junction. The patient was scheduled for an ileocoletectomy with resection of the upper rectum and ileorectostomy.

The histological examination of the resected segment showed histologic features of Crohn’s disease, a recto-sigmoid polyp with high grade.

dysplasia and extensive small lymphocytic infiltrate in both colonic and ileal wall which is strongly stained by CD20 and BCL2. The diagnosis of MALT lymphoma with adenoma on a background of Crohn’s disease was made.

The patient successfully completed 8 cycles of Rituximab+ chlorambucil chemotherapy.

Nowadays the patient is asymptomatic without evidence of lymphoproliferative recurrence 10 months after surgery.

Conclusion

We report the first case in the literature of Malt lymphoma with colonic adenoma associated with Crohn’s disease, and discuss his unique macroscopic and histological features in a patient.

Without immunosuppressive therapy.

Role of NLRP3 inflammasome in inflammatory bowel diseases

Inflammasomes are multiprotein intracellular complexes which are responsible for the activation of inflammatory responses. Among various subtypes of inflammasomes, NLRP3 has been a subject of intensive investigation. NLRP3 is considered to be a sensor of microbial and other danger signals and plays a crucial role in mucosal immune responses, promoting the maturation of proinflammatory cytokines interleukin 1β (IL-1β) and IL-18. NLRP3 inflammasome has been associated with a variety of inflammatory and autoimmune conditions, including inflammatory bowel diseases (IBD). The role of NLRP3 in IBD is not yet fully elucidated as it seems to demonstrate both pathogenic and protective effects. Studies have shown a relationship between genetic variants and mutations in NLRP3 gene with IBD pathogenesis. A complex interaction between the NLRP3 inflammasome and the mucosal immune response has been reported. Activation of the inflammasome is a key function mediated by the innate immune response and in parallel the signaling through IL-1β and IL-18 is implicated in adaptive immunity. Further research is needed to delineate the precise mechanisms of NLRP3 function in regulating immune responses. Targeting NLRP3 inflammasome and its downstream signaling will provide new insights into the development of future therapeutic strategies.

Multiplex gene expression profile in inflamed mucosa of patients with Crohn’s disease ileal localization: A pilot study

BACKGROUND

Crohn’s disease (CD) is a complex disorder resulting from the interaction of genetic, environmental, and microbial factors. The pathogenic process may potentially affect any segment of the gastrointestinal tract, but a selective location in the terminal ileum was reported in 50% of patients.

AIM

To characterize clinical sub-phenotypes (colonic and/or ileal) within the same disease, in order to identify new therapeutic targets.

METHODS

14 consecutive patients undergoing surgery for ileal CD were recruited for this study. Peripheral blood samples from each patient were collected and the main polymorphisms of the gene Card15/Nod2 (R702W, G908R, and 1007fs) were analyzed in each sample. In addition, tissue samples were taken from both the tract affected by CD and from the apparently healthy and disease-free margins (internal controls). We used a multiplex gene assay in specimens obtained from patients with ileal localization of CD to evaluate the simultaneous expression of 24 genes involved in the pathogenesis of the disease. We also processed surgery gut samples with routine light microscopy (LM) and transmission electron microscopy (TEM) techniques to evaluate their structural and ultrastructural features.

RESULTS

We found a significant increase of Th17 (IL17A and IL17F, IL 23R and CCR6) and Th1 (IFN-γ) gene expression in inflamed mucosa compared to non-inflamed sites of 14 CD patients. DEFB4 and HAMP, two genes coding for antimicrobial peptides, were also strongly activated in inflamed ileal mucosa, suggesting the overwhelming stimulation of epithelial cells by commensal microbiota. IFN-γ and CCR6 were more expressed in inflamed mucosa of CD patients with ileal localization compared with patients with colonic localization suggesting a more aggressive inflammation process in this site. Morphological analysis of the epithelial lining of Lieberkün crypts disclosed enhanced release activity from goblet mucocytes, whereas the lamina propria contained numerous cells pertaining to various lines.

CONCLUSION

We observed that the expression of ileal genes related to Th1 and Th17 activity is strongly activated as well as the expression of genes involved in microbiota regulation.

Syngeneic red blood cell-induced extracellular vesicles suppress delayed-type hypersensitivity to self-antigens in mice

BACKGROUND

At present, the role of autologous cells as antigen carriers inducing immune tolerance is appreciated. Accordingly, intravenous administration of haptenated syngeneic mouse red blood cells (sMRBC) leads to hapten-specific suppression of contact hypersensitivity (CHS) in mice, mediated by light chain-coated extracellular vesicles (EVs). Subsequent studies suggested that mice intravenously administered with sMRBC alone may also generate regulatory EVs, revealing the possible self-tolerogenic potential of autologous erythrocytes.

OBJECTIVES

The current study investigated the immune effects induced by mere intravenous administration of a high dose of sMRBC in mice.

METHODS

The self-tolerogenic potential of EVs was determined in a newly developed mouse model of delayed-type hypersensitivity (DTH) to sMRBC. The effects of EV's action on DTH effector cells were evaluated cytometrically. The suppressive activity of EVs, after coating with anti-hapten antibody light chains, was assessed in hapten-induced CHS in wild-type or miRNA-150^-/- mice.

RESULTS

Intravenous administration of sMRBC led to the generation of CD9 + CD81+ EVs that suppressed sMRBC-induced DTH in a miRNA-150-dependent manner. Furthermore, the treatment of DTH effector cells with sMRBC-induced EVs decreased the activation of T cells but enhanced their apoptosis. Finally, EVs coated with antibody light chains inhibited hapten-induced CHS.

CONCLUSIONS AND CLINICAL RELEVANCE

The current study describes a newly discovered mechanism of self-tolerance induced by the intravenous delivery of a high dose of sMRBC that is mediated by EVs in a miRNA-150-dependent manner. This mechanism implies the concept of naturally occurring immune tolerance, presumably activated by overloading of the organism with altered self-antigens.

STAT3 Genotypic Variant rs744166 and Increased Tyrosine Phosphorylation of STAT3 in IL-23 Responsive Innate Lymphoid Cells during Pathogenesis of Crohn's Disease

Crohn's disease (CD) results from dysregulated immune responses to gut microbiota in genetically susceptible individuals, affecting multiple areas of the gastrointestinal tract. Innate lymphoid cells (ILCs) are tissue-resident innate effector lymphocytes which play crucial roles in mucosal immune defense, tissue repair, and maintenance of homeostasis. The accumulation of IFN-γ-producing ILC1s and increased level of proinflammatory cytokines produced by ILCs has been observed in the inflamed terminal ileum of CD patients. To date, the precise mechanisms of ILC plasticity and gene regulatory pathways in ILCs remain unclear. Signal transducer and activator of transcription 3 (STAT3) regulates gene expression in a cell-specific, cytokine-dependent manner, involving multiple immune responses. This study proposes the positive correlation between the prevalence of STAT3 rs744166 risky allele "A" with the severity of disease in a cohort of 94 CD patients. In addition, the results suggest an increased STAT3 activity in the inflamed ileum of CD patients, compared to unaffected ileum sections. Notably, IL-23 triggers the differentiation of CD117⁺NKp44^- ILC3s and induces the activation of STAT3 in both CD117⁺NKp44^- and CD117^-NKp44^- ILC subsets, implying the involvement of STAT3 in the initiation of ILC plasticity. Moreover, carriage of STAT3 "A" risk allele exhibited a higher basal level of STAT3 tyrosine phosphorylation, and an increased IL-23 triggered the pSTAT3 level. We also demonstrated that there was no delayed dephosphorylation of STAT3 in ILCs of both A/A and G/G donors. Overall, the results of this study suggest that IL-23-induced activation of STAT3 in the CD117^-NKp44^- ILC1s involves in ILC1-to-ILC3 plasticity and a potential regulatory role of ILC1 function. Those genetically susceptible individuals carried STAT3 rs744166 risky allele appear to have higher basal and cytokine-stimulated activation of STAT3 signal, leading to prolonged inflammation and chronic relapse.

Spontaneous colitis in IL-10-deficient mice was ameliorated via inhibiting glutaminase1

Immunity imbalance and barrier damage in the intestinal mucosa are the main pathogenic factors of Crohn's disease (CD). Bis‐2‐(5‐phenylacetamido‐1,2,4‐thiadiazol‐2‐yl) ethyl sulfide (BPTES) is a glutaminase 1 (Gls1) inhibitor with the dual functions of increasing glutamine levels and immune regulation. In this study, we focused on the role of BPTES in CD‐like enteritis and the possible mechanisms. We found that Gls1 expression was significantly increased in CD intestinal tissue compared with control tissue. Bis‐2‐(5‐phenylacetamido‐1,2,4‐thiadiazol‐2‐yl) ethyl sulfide treatment significantly ameliorated chronic colitis in the IL‐10^−/−, as manifested by decreased disease activity index, body weight change, histological inflammatory degree and inflammatory cytokine expression. Bis‐2‐(5‐phenylacetamido‐1,2,4‐thiadiazol‐2‐yl) ethyl sulfide treatment exerted protective effects on CD that were associated with the maintenance of intestinal barrier integrity and the Th/Treg balance. Bis‐2‐(5‐phenylacetamido‐1,2,4‐thiadiazol‐2‐yl) ethyl sulfide treatment may act in part through TCR‐mediated mammalian target of rapamycin complex 1 (mTORC1) signalling activation. In conclusion, inhibition of Gls1 expression attenuated chronic colitis by maintaining intestinal barrier integrity and the Th/Treg balance, thereby ameliorating CD‐like colitis.

A Noninvasive Method to Assess Mucosal Healing in Patients* With Crohn's Disease

Ongoing inflammation in the gastrointestinal tract and loss of the mucosal barrier are key components of Crohn's disease. Current treatment paradigms, including treat-to-target, are based on improvement of both clinical and endoscopic symptoms. Endoscopy is an essential tool for the evaluation of mucosal healing, but patients may be reluctant to undergo repeated procedures. Surrogate markers of inflammation, such as C-reactive protein and fecal calprotectin, are being used, yet they have several limitations in the assessment of mucosal healing. A new strategy, known as the Monitr test, assesses mucosal healing status by evaluating serum levels of 13 biomarkers in patients with Crohn's disease. The 13 biomarkers are associated with cell adhesion, inflammation, angiogenesis, extracellular matrix remodeling, cell proliferation and repair, and immune cell recruitment. Monitr testing yields a mucosal healing index score that reflects disease severity. Validation of the test showed an overall accuracy of 90%, with a negative predictive value of 92% and a positive predictive value of 87% for identifying patients with endoscopic evidence of Crohn's disease. Use of this noninvasive test may aid in the monitoring and management of patients with Crohn's disease, while potentially reducing the need for repeated endoscopy.

Toll-Like Receptor-Mediated Intestinal Inflammatory Imbalance in the Pathogenesis of Necrotizing Enterocolitis

Necrotizing enterocolitis (NEC) remains the leading cause of death from gastrointestinal disease in premature infants and attacks the most fragile patients at a time when they appear to be the most stable. Despite significant advances in our overall care of the premature infant, NEC mortality remains stubbornly high. There is no specific treatment for NEC beyond broad-spectrum antibiotics and intestinal resection, and current efforts have focused on preventive strategies. Over the past decade, we have proposed a unifying hypothesis to explain the pathogenesis of NEC in premature infants that suggests that NEC develops in response to an imbalance between exaggerated proinflammatory signaling in the mucosa of the premature gut leading to mucosal injury, which is not countered effectively by endogenous repair processes, and in the setting of impaired mesenteric perfusion leads to intestinal ischemia and disease development. One of the most important pathways that mediates the balance between injury and repair in the premature intestine, and that plays a key role in NEC pathogenesis, is Toll-like receptor 4 (TLR4), which recognizes lipopolysaccharide on gram-negative bacteria. This review focuses on the role that the TLR4-mediated imbalance between proinflammatory and anti-inflammatory signaling in the premature intestinal epithelium leads to the development of NEC, and will explore how an understanding of the role of TLR4 in NEC pathogenesis has led to the identification of novel preventive or treatment approaches for this devastating disease.