Chronic Inflammatory Bowel Disease Research Articles

Identification of autophagy receptors for the Crohn's disease-associated adherent-invasive Escherichia coli.

Crohn's disease (CD) is a chronic inflammatory bowel disease, of which the etiology involves genetic, environmental and microbial factors. Adherent-invasive Escherichia coli (AIEC) and polymorphisms in autophagy-related genes have been implicated in CD etiology. Autophagy is a key process for the maintenance of cellular homeostasis, which allows the degradation of damaged cytoplasmic components and pathogens via lysosome. We have shown that a functional autophagy is necessary for AIEC clearance. Here, we aimed at identifying the autophagy receptor(s) responsible to target AIEC to autophagy for degradation. The levels of autophagy receptors p62, NDP52, NBR1, TAX1BP1 and Optineurin were knocked down in human intestinal epithelial cells T84 using siRNAs. The NDP52 knock-out (KO) and p62 KO HeLa cells, as well as NDP52 KO HeLa cells expressing the wild-type NDP52 or the mutated NDP52Val248Ala protein were used. We showed that, among the tested autophagy receptors (p62, NDP52, NBR1, TAX1BP1 and Optineurin), diminished expression of p62 or NDP52 increased the number of the clinical AIEC LF82 strain inside epithelial cells. This was associated with increased pro-inflammatory cytokine production. Moreover, p62 or NDP52 directly colocalized with AIEC LF82 and LC3, an autophagy marker. As the NDP52Val248Ala polymorphism has been associated with increased CD susceptibility, we investigated its impact on AIEC control. However, in HeLa cell and under our experimental condition, no effect of this polymorphism neither on AIEC LF82 intracellular number nor on pro-inflammatory cytokine production was observed. Together, our results suggest that p62 and NDP52 act as autophagy receptors for AIEC recognition, controlling AIEC intracellular replication and inflammation.

Abstract 2170: Effects of folic acid supplementation on early stages of colitis-associated carcinogenesis

Abstract Ulcerative colitis (UC) is a chronic inflammatory bowel disease (IBD) characterized by persistent mucosal inflammation extending throughout the colon. Due to compromised intestinal surface integrity and the prolonged use of medication, individuals with UC often develop a folate deficiency, requiring folic acid (FA) supplementation. Prior findings from this group indicate that FA supplementation, at clinically relevant levels, promotes UC-associated dysplasia. Supplementation with FA resulted in an increased multiplicity of dysplasia and a significant elevation in the expression of several inflammatory genes (e.g. IL-6, Cox-2, Iκκ-β) within the colonic mucosa of mice with UC. Genome-wide expression profiling of normal and dysplastic colonic epithelial cells from mice treated with different doses of FA revealed differentially expressed genes were enriched for members of the ERK and NF-κB pathways. Subsequent in vitro analyses, utilizing isogenic RKO colon adenocarcinoma cells exposed to various doses of FA, demonstrated the downregulation of ERK and p-ERK in wild type (WT) p53+/+ cells, while an increase in expression was observed in p53−/− cells at the protein level. The goal of this study is to investigate the role of the MAPK/ERK pathway in the development of UC-associated neoplasms. An in vitro model that faithfully reproduces the inflamed microenvironment in the context of WT vs. mutant p53, the putative gatekeeper of UC-associated carcinogenesis, is needed to enhance our understanding of early changes in the colon that are induced by FA and drive tumor formation. Colon organoids are being generated by isolating crypts from WT p53+/+ and mutant p53+/515A mice. These organoids are then co-cultured with mouse macrophages (RAW264.7 cells) in inserts to stimulate crosstalk between the macrophages and colonic epithelial cells, as in the inflamed colon. Analyses demonstrate that the macrophages express pivotal inflammatory cytokines characteristic of UC, including IL-1β, IL-10, TNF-α, and IL-6, irrespective of the presence or absence of LPS stimulation. Co-cultured organoids and macrophages will be exposed to different concentrations of FA for various lengths of time, and the impact of treatment on the levels of ERK, p-ERK, and p65 will be assessed. The ability of p-ERK to mediate the transcriptional activation of NF-κB and its downstream effector IL-6 will also be evaluated. Subsequent investigations employing this innovative experimental model will reveal the mechanisms by which FA supplementation promotes the progression of UC-associated dysplasia. Given the potential risks associated with FA supplementation in individuals with UC, there is an urgent need to translate these results to a clinical setting. (Supported by CA262551 and the Timothy and Aurora Hughes Cancer Research Fund). Citation Format: Ariane Rocha Bartolomeu, Wen-Chi Chang, Lisa Vanderveer, Kristen N. Harvey, Mitchell Cheung, Harry S. Cooper, Margie Lee Clapper. Effects of folic acid supplementation on early stages of colitis-associated carcinogenesis [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2024; Part 1 (Regular Abstracts); 2024 Apr 5-10; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2024;84(6_Suppl):Abstract nr 2170.

Scoring Abdominal Symptoms in People with Cystic Fibrosis.

(1) Background: The introduction of highly effective CFTR-modulating therapies (HEMT) has changed the course of the disease for many people with Cystic Fibrosis (pwCF). Attention previously focused on life-threatening conditions of the respiratory system has broadened, bringing the involvement of the digestive system into the clinical and scientific focus. This emphasized the need for sensitive tools to capture and quantify changes in abdominal symptoms (AS), ideally applying patient-reported outcome measures (PROMs). (2) Methods: The present review focuses on studies addressing AS assessment deriving from the multi-organic abdominal involvement in pwCF. Among 5224 publications retrieved until Nov. 2022, 88 were eligible, and 39 were finally included. (3) Results: The review reveals that for a long time, especially before HEMT availability, AS in pwCF were assessed by single questions on abdominal complaints or non-validated questionnaires. PROMs focusing on quality of life (QOL) including a few GI-related questions were applied. Likewise, PROMs developed and partially validated for other non-CF GI pathologies, such as chronic inflammatory bowel diseases, irritable bowel syndrome, gastroesophageal reflux, constipation, or pancreatitis, were implemented. (4) Conclusions: Only lately, CF-specific GI-PROMs have been developed and validated following FDA guidelines, showing high sensitivity to changes and capturing marked and statistically significant reductions in the burden of AS achieved with HEMT implementation.

Comparative analysis of single-cell transcriptome reveals heterogeneity and commonality in the immune microenvironment of colorectal cancer and inflammatory bowel disease.

During aging, chronic inflammation can promote tumor development and metastasis. Patients with chronic inflammatory bowel diseases (IBD) are at an increased risk of developing colorectal cancer (CRC). However, the molecular mechanism underlying is still unclear. We conducted a large-scale single-cell sequencing analysis comprising 432,314 single cells from 92 CRC and 24 IBD patients. The analysis focused on the heterogeneity and commonality of CRC and IBD with respect to immune cell landscape, cellular communication, aging and inflammatory response, and Meta programs. The CRC and IBD had significantly different propensities in terms of cell proportions, differential genes and their functions, and cellular communication. The progression of CRC was mainly associated with epithelial cells, fibroblasts, and monocyte-macrophages, which displayed pronounced metabolic functions. In particular, monocyte-macrophages were enriched for the aging and inflammation-associated NF-κB pathway. And IBD was enriched in immune-related functions with B cells and T cells. Cellular communication analysis in CRC samples displayed an increase in MIF signaling from epithelial cells to T cells, and an increase in the efferent signal of senescence-associated SPP1 signaling from monocyte-macrophages. Notably, we also found some commonalities between CRC and IBD. The efferent and afferent signals showed that the pro-inflammatory cytokine played an important role. And the activity of aging and inflammatory response with AUCell analysis also showed a high degree of commonality. Furthermore, using the Meta programs (MPs) with the NMF algorithm, we found that the CRC non-malignant cells shared a substantial proportion of the MP genes with CRC malignant cells (68% overlap) and IBD epithelial cells (52% overlap), respectively. And it was extensively involved in functions of cell cycle and immune response, revealing its dual properties of inflammation and cancer. In addition, CRC malignant and non-malignant cells were enriched for the senescence-related cell cycle G2M phase transition and the p53 signaling pathway. Our study highlights the characteristics of aging, inflammation and tumor in CRC and IBD at the single-cell level, and the dual property of inflammation-cancer in CRC non-malignant cells may provide a more up-to-date understanding of disease transformation.

Clinical outcomes and perioperative morbidity and mortality following segmental resections of the colon for Crohn’s colitis

IntroductionCrohn’s disease (CD) is a chronic inflammatory bowel disease of a multifactorial pathogenesis. Recently numerous genetic variants linked to an aggressive phenotype were identified, leading to a progress in therapeutic options, resulting in a decreased necessity for surgery. Nevertheless, surgery is often inevitable. The aim of the study was to evaluate possible risk factors for postoperative complications and disease recurrence specifically after colonic resections for CD.Patients and methodsA total of 241 patients who underwent colonic and ileocaecal resections for CD at our instiution between 2008 and 2018 were included. All data was extracted from clinical charts.ResultsMajor complications occurred in 23.8% of all patients. Patients after colonic resections showed a significantly higher rate of major postoperative complications compared to patients after ICR (p = < 0.0001). The most common complications after colonic resections were postoperative bleeding (22.2%), the need for revision surgery (27.4%) and ICU (17.2%) or hospital readmission (15%). As risk factors for the latter, we identified time interval between admission and surgery (p = 0.015) and the duration of the surgery (p = 0.001). Isolated distal resections had a higher risk for revision surgery and a secondary stoma (p = 0.019). Within the total study population, previous bowel resections (p = 0.037) were identified as independent risk factors for major perioperative complications.ConclusionThe results indicate that both a complex surgical site and a complex surgical procedure lead to a higher perioperative morbidity in colonic resections for Crohn’s colitis.

Simple and versatile in situ thermo-sensitive hydrogel for rectal administration of SZ-A to alleviate inflammation and repair mucosal barrier in ulcerative colitis

Ulcerative colitis (UC) is a chronic inflammatory bowel disease characterized by persistent inflammation of the colon and disrupted intestinal function. Ramulus mori (Sangzhi) alkaloids (SZ-A), derived from twigs of mulberry, were approved by the National Medical Products Administration in 2020 for treating type 2 diabetes mellitus. Accumulated evidence has confirmed that SZ-A also alleviates non-alcoholic fatty liver disease and ameliorates inflammation, indicating its potential to address inflammation in UC. However, the treatment of UC faces challenges due to low drug delivery efficiency and short retention time. To overcome these challenges, an injectable and adherent in-situ thermo-sensitive hydrogel containing SZ-A was developed for rectal drug delivery, utilizing the thermo-sensitive polymers Poloxamer 407 and 188. The thermo-sensitive hydrogel system was designed with a moderate gelation temperature of 32 ± 0.5 °C, a short gelation time of 64 s, a pH range of 7–10, high moisturizing capability exceeding 90%, and moderate mechanical strength of 4–5 s. In a rat model with UC, the in situ thermo-sensitive hydrogel significantly extended the retention time at the colonic site and enabled sustained release after rectal administration. Symptoms of UC were markedly reduced following rectal administration of SZ-A thermo-sensitive hydrogel. Furthermore, the release of inflammatory factors, such as interleukin-1β (IL-1β), IL-6, IL-18, tumor necrosis factor-α (TNF-α), and transforming growth factor-β1 (TGF-β1), significantly decreased in the SZ-A thermo-sensitive hydrogel group. The integrity of the colonic mucosal barrier was significantly enhanced following the application of SZ-A thermo-sensitive hydrogel. In conclusion, rectal administration of SZ-A in situ thermo-sensitive hydrogel effectively alleviated UC symptoms, inhibited the secretion of inflammatory factors, and promoted the repair of the colonic mucosal barrier. This approach holds promise as a potential treatment for UC.

Investigating the association between the tissue expression of miRNA-101, JAK2/STAT3 with TNF-α, IL-6, IL-1β, and IL-10 cytokines in the ulcerative colitis patients.

Ulcerative colitis (UC) is a chronic inflammatory bowel disease caused by numerous factors, such as immune system dysfunction and genetic factors. MicroRNAs (miRNAs) play a crucial role in UC pathogenesis, particularly via the JAK-STAT pathway. Our aim was to investigate the association between miRNA-101 and JAK2-STAT3 signaling pathway with inflammatory cytokines in UC patients. We enrolled 35 UC patients and 35 healthy individuals as the control group, referred to Shariati Hospital, Tehran, Iran. Patients were diagnosed based on clinical, laboratory, histological, and colonoscopy criteria. RNA and protein extracted from tissue samples. Real-time PCR was used to assess the expression levels of miRNA-101, interleukin (IL)-1β, IL-6, tumor necrosis factor (TNF)-α, and IL-10 genes, while western blot was employed to measure levels of P-STAT3, total STAT3, and JAK2 proteins. Expression of pro-inflammatory cytokines TNF-α, IL-1β, and IL-6 significantly increased, while the expression of IL-10 significantly decreased in the case group versus controls. Additionally, miRNA-101 expression was significantly higher in UC patients. A significant correlation between miRNA-101 and IL-6 expression was observed, indicating their relationship and possible impact on cell signaling pathways, JAK2-STAT3. No significant changes were observed in phosphorylated and total STAT3 and JAK2 protein expression. This study provides evidence of increased miRNA-101 expression in UC tissue, suggesting a potential correlation between miRNA-101 and IL-6 expression and their involvement in the JAK2-STAT3 pathway. The study confirms alterations in UC patients' pro-inflammatory cytokines and anti-inflammatory IL-10. However, further investigations are needed to understand the exact role of miRNA-101 in UC pathogenesis fully.

Efficacy and safety of moxibustion for ulcerative colitis: protocol for a systematic review and meta-analysis

IntroductionUlcerative colitis (UC) is a global chronic inflammatory bowel disease, and the poor efficacy of currently available pharmacological regimens makes the management of UC a great challenge. Moxibustion has shown...

The relationship between extreme inter-individual variation in macrophage gene expression and genetic susceptibility to inflammatory bowel disease

The differentiation of resident intestinal macrophages from blood monocytes depends upon signals from the macrophage colony-stimulating factor receptor (CSF1R). Analysis of genome-wide association studies (GWAS) indicates that dysregulation of macrophage differentiation and response to microorganisms contributes to susceptibility to chronic inflammatory bowel disease (IBD). Here, we analyzed transcriptomic variation in monocyte-derived macrophages (MDM) from affected and unaffected sib pairs/trios from 22 IBD families and 6 healthy controls. Transcriptional network analysis of the data revealed no overall or inter-sib distinction between affected and unaffected individuals in basal gene expression or the temporal response to lipopolysaccharide (LPS). However, the basal or LPS-inducible expression of individual genes varied independently by as much as 100-fold between subjects. Extreme independent variation in the expression of pairs of HLA-associated transcripts (HLA-B/C, HLA-A/F and HLA-DRB1/DRB5) in macrophages was associated with HLA genotype. Correlation analysis indicated the downstream impacts of variation in the immediate early response to LPS. For example, variation in early expression of IL1B was significantly associated with local SNV genotype and with subsequent peak expression of target genes including IL23A, CXCL1, CXCL3, CXCL8 and NLRP3. Similarly, variation in early IFNB1 expression was correlated with subsequent expression of IFN target genes. Our results support the view that gene-specific dysregulation in macrophage adaptation to the intestinal milieu is associated with genetic susceptibility to IBD.

Особливості перебігу вагітності та пологів у жінок із запальними захворюваннями кишечника

The problem of pregnancy management in women with inflammatory bowel diseases is becoming more urgent, due to the prevalence of such pathologies as Crohn's disease and ulcerative colitis in the age group of women 20-40 years old, during which reproductive function is mainly being realized. Purpose - to investigate the course of pregnancy and labour in women whose pregnancy occurred on the background of the existing Crohn’s disease and ulcerative colitis. Materials and methods. The main group (the Group I) included women with chronic inflammatory bowel diseases - Crohn’s disease (the Group I-A; n=27) and ulcerative colitis (the Group I-B; n=52); the control group (n=20) consisted of women without severe somatic pathology. Retrospective clinical and statistical analysis was performed using data from medical documentation. Obtained results were statistically processed in specialized programs. Results. A statistically higher frequency of pregnancy complications was found in women with inflammatory bowel diseases, such as anemia (59.3% in the Group I-A and 69.2% in the Group I-B versus 30% in the control group); threatening abortion (40.7% in the Group I-A and 53.8% in the Group I-B against 15% in the control group); hyperemesis gravidarum (44.4% in the Group I-A and 67.3% in the Group I-B against 25% in the control group); preeclampsia (37% in the Group I-A and 44.2% in the Group I-B against 10% in the control group); premature rupture of fetal membranes (37% in the Group I-A and 21.1% in the Group I-B against 10% in the control group). At the same time, women of the main group had an earlier development of spontaneous labor and a slightly smaller mass of newborns. Conclusions. Received results indicate presence of Crohn's disease and ulcerative colitis influence on the course of pregnancy in women, which requires joint management of such women with gastroenterologists. The research was carried out in accordance with the principles of the Helsinki Declaration. The study protocol was approved by the Local Ethics Committee of the participating institution. The informed consent of the patient was obtained for conducting the studies. No conflict of interests was declared by the authors.

Хронічний коліт у дітей. Проблеми диференціальної діагностики

During the last few decades, there has been observed a "rejuvenation" of the inflammatory bowel diseases (IBD) onset in childhood. Very often the problem is narrowed down to the differential diagnosis of Crohn's disease and ulcerative colitis, which are related to IBD, although in reality the spectrum of chronic IBD is much wider. A diagnosed case of microscopic (collagenous) colitis confirms the need for a wide diagnostic search in patients with IBD. Purpose - to describe differential diagnostic features of collagenous colitis and collagenous gastritis in young children. Clinical case. Observational data on a patient aged 1 year and 7 months with a special form of colitis (collagenous colitis in combination with collagenous gastritis) are presented. The peculiarities of this rare disease course in the examined patient, in whom the pathology debuted with gastric ulcers with hematemesis, anemia and diarrhea syndrome, were analyzed. The differential search complex stages are discussed in detail, the results of laboratory, instrumental and pathomorphological research methods are described. Information is provided on the treatment prospects of patients with a gastrointestinal tract collagenous pathological process. There is a justified need to take into account rare causes of digestive tract inflammation when observing young patients with a clinical picture similar to the IBD debut. The research was carried out in accordance with the principles of the Declaration of Helsinki. The informed consent of the child's parents was obtained for conducting the studies. No conflict of interests was declared by the authors.

Identification and immunoinfiltration analysis of key genes in ulcerative colitis using WGCNA.

Ulcerative colitis (UC) is a chronic non-specific inflammatory bowel disease characterized by an unclear pathogenesis. This study aims to screen out key genes related to UC pathogenesis. Bioinformatics analysis was conducted for screening key genes linked to UC pathogenesis, and the expression of the screened key genes was verified by establishing a UC mouse model. Through bioinformatics analysis, five key genes were obtained. Subsequent infiltration analysis revealed seven significantly different immune cell types between the UC and general samples. Additionally, animal experiment results illustrated markedly decreased body weight, visible colonic shortening and damage, along with a significant increase in the DAI score of the DSS-induced mice in the UC group in comparison with the NC group. In addition, H&E staining results demonstrated histological changes including marked inflammatory cell infiltration, loss of crypts, and epithelial destruction in the colon mucosa epithelium. qRT-PCR analysis indicated a down-regulation of ABCG2 and an up-regulation of IL1RN, REG4, SERPINB5 and TRIM29 in the UC mouse model. Notably, this observed trend showed a significant dependence on the concentration of DSS, with the mouse model of UC induced by 7% DSS demonstrating a more severe disease state compared to that induced by 5% DSS. ABCG2, IL1RN, REG4, SERPINB5 and TRIM29 were screened out as key genes related to UC by bioinformatics analysis. The expression of ABCG2 was down-regulated, and that of IL1RN, REG4, SERPINB5 and TRIM29 were up-regulated in UC mice as revealed by animal experiments.

The Peptide LLTRAGL Derived from Rapana venosa Exerts Protective Effect against Inflammatory Bowel Disease in Zebrafish Model by Regulating Multi-Pathways.

Inflammatory bowel disease (IBD) is a chronic inflammatory bowel disease with unknown pathogenesis which has been gradually considered a public health challenge worldwide. Peptides derived from Rapana venosa have been shown to have an anti-inflammatory effect. In this study, peptide LLTRAGL derived from Rapana venosa was prepared by a solid phase synthesis technique. The protective effects of LLTRAGL were studied in a 2,4,6-trinitrobenzene sulfonic acid (TNBS)-induced zebrafish colitis model. The underlying mechanisms of LLTRAGL were predicted and validated by transcriptome, real-time quantitative PCR assays and molecular docking. The results showed that LLTRAGL reduced the number of macrophages migrating to the intestine, enhanced the frequency and rate of intestinal peristalsis and improved intestinal inflammatory damage. Furthermore, transcriptome analysis indicated the key pathways (NOD-like receptor signal pathway and necroptosis pathway) that link the underlying protective effects of LLTRAGL's molecular mechanisms. In addition, the related genes in these pathways exhibited different expressions after TNBS treatment. Finally, molecular docking techniques further verified the RNA-sequencing results. In summary, LLTRAGL exerted protective effects in the model of TNBS-induced colitis zebrafish. Our findings provide valuable information for the future application of LLTRAGL in IBD.

Enhancing Calprotectin's Predictive Power as a Biomarker of Endoscopic Activity in Ulcerative Colitis: A Machine Learning Use Case.

Ulcerative colitis (UC) is a chronic inflammatory bowel disease characterized by periods of exacerbation and remission, making disease monitoring and management challenging. Endoscopy, the gold standard for assessing disease activity and severity, involves invasive procedures and is associated with patient discomfort and risks. Using machine learning (ML) to combine fecal calprotectin with other clinical or biological tests can significantly enhance the non-invasive prediction of endoscopic disease activity (EDA) in UC. Aim: To prove that by fusing fecal calprotectin with other clinical data into an ML model, the performance of the non-invasive prediction of EDA can be significantly improved. Methods: We conducted a prospective, observational, single-center study encompassing 103 patients diagnosed with UC. We employed multilayer perceptron models as the core ML algorithm for predicting EDA. For the constructed models, we utilized the varImp function from the caret library in R to assess the significance of each variable in predicting the outcome. Results: Calprotectin as a sole predictor obtained an accuracy of 70% and an area under the curve (AUC) of 0.68. Combining calprotectin with the list of selected predictors that were fed to the MLP models improved accuracy and the AUC. The accuracy of the algorithm on the test set was 85%. Similarly, the AUC increased to 0.93. This is the first study to propose the use of calprotectin as a predictor in an ML model to estimate UC endoscopic disease activity. Conclusion: The deployment of this ML model can furnish doctors and patients with valuable evaluation of endoscopic disease activity which can be highly beneficial for individuals with UC who need long-term treatment.

Crohn's Patient Serum Proteomics Reveals Response Signature for Infliximab but not Vedolizumab.

Crohn's disease is a chronic inflammatory bowel disease that affects the gastrointestinal tract. Common biologic families used to treat Crohn's are tumor necrosis factor (TNF)-α blockers (infliximab and adalimumab) and immune cell adhesion blockers (vedolizumab). Given their differing mechanisms of action, the ability to monitor response and predict treatment efficacy via easy-to-obtain blood draws remains an unmet need. To investigate these gaps in knowledge, we leveraged 2 prospective cohorts (LOVE-CD, TAILORIX) and profiled their serum using high-dimensional isobaric-labeled proteomics before treatment and 6 weeks after treatment initiation with either vedolizumab or infliximab. The proportion of patients endoscopically responding to treatment was comparable among infliximab and vedolizumab cohorts; however, the impact of vedolizumab on patient sera was negligible. In contrast, infliximab treatment induced a robust response including increased blood-gas regulatory response proteins, and concomitant decreases in inflammation-related proteins. Further analysis comparing infliximab responders and nonresponders revealed a lingering innate immune enrichments in nonresponders and a unique protease regulation signature related to clotting cascades in responders. Lastly, using samples prior to infliximab treatment, we highlight serum protein biomarkers that potentially predict a positive response to infliximab treatment. These results will positively impact the determination of appropriate patient treatment and inform the selection of clinical trial outcome metrics.

A Child with Crohn's Disease: Problems and Stress Level of Parents-Caregivers-A Cross-Sectional Study.

Crohn's disease (CD) is a chronic inflammatory bowel disease. The perception of the disease, its troublesome symptoms and the highly involved treatment mean that living with CD requires not only the affected child having to learn to cope with it, but also their parents. The aim of the study was to examine the problems and levels of stress in parents-caregivers of children with CD. The study was cross-sectional and conducted using the diagnostic survey method. An original questionnaire was used to assess the socio-demographic situation and problems of caring for a child with CD, and the standardised PSS-10 questionnaire was added. The study group consisted of 60 parents who accompanied their children during hospitalization. The surveyed caregivers of children with CD found it difficult to maintain a specialised diet and deal with the need for hospitalization and the chronic use of medications. Access to the necessary knowledge about the disease posed the least difficulty in everyday life for a child with CD. The vast majority of parents (50, 83.34%) felt a high level of stress related to caring for a child with CD and, simultaneously, a lack of acceptance of the child's disease (39, 65%). The age of the respondents did not have a statistically significant effect on the occurrence of problems related to everyday functioning. The acceptance of the child's disease by the parents and informal caregivers of children with CD reduced their stress level. Parents could count on support from their relatives but, unfortunately, institutional support was not properly provided.

Assessing the impact of mRNA vaccination in chronic inflammatory murine model

The implications of administration of mRNA vaccines to individuals with chronic inflammatory diseases, including myocarditis, rheumatoid arthritis (RA), and inflammatory bowel disease (IBD), are unclear. We investigated mRNA vaccine effects in a chronic inflammation mouse model implanted with an LPS pump, focusing on toxicity and immunogenicity. Under chronic inflammation, mRNA vaccines exacerbated cardiac damage and myocarditis, inducing mild heart inflammation with heightened pro-inflammatory cytokine production and inflammatory cell infiltration in the heart. Concurrently, significant muscle damage occurred, with disturbances in mitochondrial fusion and fission factors signaling impaired muscle repair. However, chronic inflammation did not adversely affect muscles at the vaccination site or humoral immune responses; nevertheless, it partially reduced the cell-mediated immune response, particularly T-cell activation. These findings underscore the importance of addressing mRNA vaccine toxicity and immunogenicity in the context of chronic inflammation, ensuring their safe and effective utilization, particularly among vulnerable populations with immune-mediated inflammatory diseases.

A244 DEVELOPING AND ASSESSING THE EFFECTIVENESS OF A REMOTE MONITORING PROTOCOL FOR ULCERATIVE COLITIS PATIENTS - ULCERATIVE COLITIS CLINICAL OUTREACH (UCCO)

Abstract Background Ulcerative colitis (UC) is a chronic inflammatory bowel disease which requires regular gastroenterologist monitoring. Outpatient monitoring programs to date have focused on clinical scores alone, leaving patients with asymptomatic inflammation susceptible to undertreatment despite increased risk of flares and colorectal cancer. The University of Alberta IBD Unit developed and piloted an outreach and remote monitoring protocol for UC patients including clinical and biochemical variables. We assessed the effectiveness of this protocol at improving UC care. Aims This study aimed to develop a clinical outreach and remote patient monitoring protocol for UC patients and assess the impact this protocol had on disease management. Methods Biologic naïve adult UC patients who had not been reviewed by their gastroenterologist in at least six months were contacted by phone and mailed monitoring kits with Partial Mayo, Sutherland Index, and medication adherence questionnaires and a requisition for blood work and fecal calprotectin (FCP). Results were compiled and sent to each patient’s gastroenterologist. Participating gastroenterologists completed a survey about the perceived utility of the protocol and intended UC management changes. Results 85 patients completed the protocol. 86.4% of physician surveys rated the protocol as helpful to clinicians. UC management was changed in 55.6% of cases, with 82.2% of changes being management escalations. Six patients had active flares and 17 patients with asymptomatic inflammation were identified. Endoscopy was completed for 23 patients, with active disease observed in 78.2% of cases. Six patients started biologic therapies based on the protocol and endoscopic findings. UC management escalations were significantly predicted by FCP and Sutherland Index scores on logistic regression analysis. Conclusions This protocol had a meaningful impact on UC management and identified patients with active disease in both the presence and absence of clinical remission. Remote outpatient monitoring in UC should include collection of both FCP and clinical scores every six months to improve UC management. Funding Agencies None

Emerging role of exosomes in ulcerative colitis: Targeting NOD-like receptor family pyrin domain containing 3 inflammasome.

Ulcerative colitis (UC) is a chronic recurrent inflammatory bowel disease. Despite ongoing advances in our understanding of UC, its pathogenesis is yet unelucidated, underscoring the urgent need for novel treatment strategies for patients with UC. Exosomes are nanoscale membrane particles that mediate intercellular communication by carrying various bioactive molecules, such as proteins, RNAs, DNA, and metabolites. The NOD-like receptor family pyrin domain containing 3 (NLRP3) inflammasome is a cytosolic tripartite protein complex whose activation induces the maturation and secretion of proinflammatory cytokines interleukin-1β (IL-1β) and IL-18, triggering the inflammatory response to a pathogenic agent or injury. Growing evidence suggests that exosomes are new modulators of the NLRP3 inflammasome, with vital roles in the pathological process of UC. Here, recent evidence is reviewed on the role of exosomes and NLRP3 inflammasome in UC. First, the dual role of exosomes on NLRP3 inflammasome and the effect of NLRP3 inflammasome on exosome secretion are summarized. Finally, an outlook on the directions of exosome-NLRP3 inflammasome crosstalk research in the context of UC is proposed and areas of further research on this topic are highlighted.

A37 POSTBIOTIC BACTERIAL MEMBRANE VESICLES FROM B. SUBTILIS DELIVER NOD2 LIGANDS AND PROMOTE IN VITRO WOUND RE-EPITHLIALIZATION THROUGH RIPK2 SIGNALING

Abstract Background Bacterial membrane vesicles (MVs) are bilipid nanoparticles secreted as a conserved method of intercellular communication. MVs from Gram-positive bacteria carry diverse bacterial products and represent a unique opportunity in the growing field of postbiotics. This native machinery for mediating microbe-host interactions makes MVs a promising tool for intestinal drug delivery in the context of Crohn’s disease (CD). CD is a chronic inflammatory bowel disease characterized by relapsing inflammation of the digestive tract. CD is associated with (1) loss of function mutations in the host gene encoding the nuclear-binding oligomerization domain 2 (NOD2) pattern recognition receptor and (2) a gut microbiome with reduced capabilities to generate NOD2 stimulating muropeptides from peptidoglycan. Nod2-/- mice have decreased barrier integrity and impaired epithelial restitution upon challenge. However, there are currently no therapeutic strategies targeting NOD2 for CD management. Aims The aims of this study were to (1) leverage MVs as a biological system for NOD2 ligand delivery to intestinal epithelial cells and (2) determine the roll of probiotic MVs and bacterial ligand synergy in wound re-epithelialization. Methods MVs were purified from B. subtilis through filtration and ultracentrifugation. MVs were characterized through nanoparticle tracking analysis using NanoSight300. WT and NOD2-/- HCT116 cells, a human colorectal carcinoma cell line, were utilized for IL-8 secretion quantification by ELISA, gene expression by qPCR, and in vitro scratch wound assay by Incucyte quantification. Results Here, we demonstrate for the first time that MVs from B. subtilis deliver NOD2 ligands in vitro. Treatment with isolated MVs induces IL8 secretion and CXCL1 expression in a NOD2-dependent manner. Furthermore, MVs promote re-epithelialization after in vitro scratch wounding. This effect was completely blunted by the addition of an inhibitor for RIPK2, a downstream transducer required for NOD2 signaling. Through bacterial pathogen-associated molecular patterns (PAMPs) screening, we found that wound re-epithelialization is promoted by PAMP synergy but dependent on RIPK2 signaling. Conclusions This work suggests that delivery of muropeptides by probiotic-derived MVs is a promising strategy to promote epithelial regeneration during injury through targeting NOD2. Future directions will work towards validating these findings in human ileal primary cells and murine models of intestinal injury. Funding Agencies CIHRMedicine by Design