Active Crohn's Disease Patients Research Articles

Gut microbiota composition in patients with Crohn's disease in Saudi Arabia.

Crohn's disease (CD) entails intricate interactions with gut microbiome diversity, richness, and composition. The relationship between CD and gut microbiome is not clearly understood and has not been previously characterized in Saudi Arabia. We performed statistical analysis about various factors influencing CD activity and microbiota dysbiosis, including diagnosis, treatment, and its impact on their quality of life as well as high-throughput metagenomic V3-V4 16S rRNA encoding gene hypervariable region of a total of eighty patients with CD, both in its active and inactive state with healthy controls. The results were correlated with the demographic and lifestyle information, which the participants provided via a questionnaire. α-diversity measures indicated lower bacterial diversity and richness in the active and inactive CD groups compared to the control group. Greater dysbiosis was observed in the active CD patients compared to the inactive form of the disease, showed by a reduction in microbial diversity. Specific pathogenic bacteria such as Filifactor, Peptoniphilus, and Sellimonas were identified as characteristic of CD groups. In contrast, anti-inflammatory bacteria like Defluviitalea, Papillibacter, and Petroclostridium were associated with the control group. Among the various factors influencing disease activity and microbiota dysbiosis, smoking emerged as the most significant, with reduced α-diversity and richness for the smokers in all groups, and proinflammatory Fusobacteria was more present (p<0.05). Opposite to the control group, microbial diversity and richness were lower in CD participants of older age compared to younger ones, and male CD participants showed less diversity compared to women participants from the same groups. Our results describe the first report on the relationship between microbiota and Crohn's disease progress in Saudi Arabia, which may provide a theoretical basis for the application of therapeutic methods to regulate gut microbes in CD.

Application of Dynamic Contrast-Enhanced Ultrasound in Evaluation the Activity of Crohn's Disease.

The dynamic assessment of disease activity during the follow-up of patients with Crohn's disease (CD) remains a significant challenge. In this study, we aimed to identify the role of dynamic contrast-enhanced ultrasound (DCE-US) in the evaluation of activity of CD. In the retrospective study, patients diagnosed with CD in our hospital were included. All the diagnoses were confirmed by clinical symptoms and ileocolonoscopical results. All patients underwent intestinal ultrasound and contrast-enhanced ultrasound (CEUS) examinations within 1 week of the ileocolonoscopy examinations. Acuson Sequoia (Siemens Healthineers, Mountain View, CA, USA) and Resona R9 Elite (Mindray Medical Systems, China) with curved array and Line array transducers were used. The CEUS examination was performed with SonoVue (Bracco SpA, Milan, Italy). DCE-US analysis was performed by UltraOffice (version: 0.3-2010, Mindray Medical Systems, China) software. Two regions of interest (ROIs) were set in the anterior section of the infected bowel wall and its surrounding normal bowel wall 2 cm distant from the inflamed area. Time-intensity curves (TICs) were generated and quantitative perfusion parameters were obtained after curve fittings. The Simple Endoscopic Score for Crohn's disease (SES-CD) was regarded as the reference standard to evaluate the activity of CD. The receiver operating characteristic curve (ROC) analyses were used to determine the diagnostic efficiency of DCE-US quantitative parameters. From March 2023 to November 2023, 52 CD patients were included. According to SES-CD score, all patients were divided into active group with the SES-CD score > 5 (n = 39) and inactive group SES-CD score < 5 (n = 13). Most of the active CD patients showed bowel wall thickness (BWT) > 4.2 mm (97.4%, 38/39) or mesenteric fat hypertrophy (MFH) on intestinal ultrasound (US) scan (69.2%, 27/39). Color Doppler signal of the bowel wall mostly showed spotty or short striped blood flow signal in active CD patients (56.4%, 22/39). According to CEUS enhancement patterns, most active CD patients showed a complete hyperenhancement of the entire intestinal wall (61.5%, 24/39). The TICs of active CD showed an earlier enhancement, higher peak intensity, and faster decline. Among all CEUS quantitative parameters, amplitude-derived parameters peak enhancement (PE), wash-in area under the curve (WiAUC), wash-in rate (WiR), wash-in perfusion index (WiPI), and wash-out rate (WoR) were significantly higher in active CD than in inactive CD (p < 0.05). The combined AUROC of intestinal ultrasound features and DCE-US quantitative perfusion parameters in the diagnosis of active CD was 0.987, with 97.4% sensitivity, 100% specificity, and 98.1% accuracy. DCE-US with quantitative perfusion parameters is a potential useful noninvasive imaging method to evaluate the activity of Crohn's disease.

In vitro mucin degradation and paracellular permeability by fecal water from Crohn's disease patients.

Aim: This study aimed to examine the impact of fecal water (FW) of active and remissive Crohn's disease (CD) patients on mucin degradation and epithelial barrier function. Methods: FW and bacterial membrane vesicles (MVs) were isolated from fresh fecal samples of six healthy controls (HCs) and 12CD patients. Bacterial composition was determined by 16S rRNA gene amplicon sequencing. Results: In vitro FW-induced mucin degradation was higher in CD samples versusHC (p<0.01), but not associated with specific bacterial genera. FW of three remissive samples decreased transepithelial electrical resistance in Caco-2 cells by 78-87% (p<0.001). MVs did not induce barrier alterations. Conclusion: The higher mucin-degradation capacity of CD-derived FW might suggest contributions of microbial products to CD pathophysiology.

Hyperactivation and enhanced cytotoxicity of reduced CD8+ gamma delta T cells in the intestine of patients with Crohn’s disease correlates with disease activity

Background and aimsWe aimed to investigate the immune characteristics of intestinal CD8+ gamma delta T (CD8+ γδ T) cells in Crohn’s disease (CD) and their correlation with disease activity.MethodsThe study cohorts included 21 CD patients and 21 healthy individuals. CD8+ γδ T cells were isolated from human ileal mucosa for detection by flow cytometry. The activation or inhibition status of cells was detected by detecting the expression of activation marker HLA-DR and the immunosuppressive molecule PD-1 on cells. The cytotoxicity of cells was assessed by detecting the expression of cytotoxic molecules (Perforin, Granzyme B, and TRAIL) in cells. Ratios of investigated cells were calculated as prediction factors by receiver operating characteristic curve (ROC) analysis.ResultsThe study revealed a reduction in intestinal CD8+ γδT cells among active CD patients, with a more pronounced reduction observed in moderately active patients compared to mildly active patients. Moreover, active CD patients exhibited heightened activation levels in their intestinal CD8+ γδT cells, whereas the activation was comparatively weakened in moderately active patients compared with mildly active patients. Additionally, the cytotoxicity of intestinal CD8+ γδT cells was enhanced solely in mildly active patients, while it was impaired in moderately active patients compared with mildly active patients. Furthermore, HLA-DR+ CD8+ γδT cell ratio, CD8+ γδT ratio, and CD8+ γδT count were identified as indicators in the diagnosis of active CD. Meanwhile, the ratios of Granzyme B+ CD8+ γδT cell and Perforin+ CD8+ γδT cell were identified as indicators that distinguish mildly moderately active CD cases.ConclusionsIntestinal CD8+ γδT was reduced in active CD patients, but their activation and cytotoxicity were enhanced. However, with increased disease activity, intestinal CD8+ γδ T cells became dysfunctional. CD-specific perturbations observed in various phenotypic markers in CD8+ γδ T cells can be used as indicators to assist in diagnosing CD patients.

Antibiotic Therapy for Active Crohn's Disease Targeting Pathogens: An Overview and Update.

Crohn's disease (CD) is a multifactorial chronic disorder that involves a combination of factors, including genetics, immune response, and gut microbiota. Therapy includes salicylates, immunosuppressive agents, corticosteroids, and biologic drugs. International guidelines do not recommend the use of antibiotics for CD patients, except in the case of septic complications. Increasing evidence of the involvement of gut bacteria in this chronic disease supports the rationale for using antibiotics as the primary treatment for active CD. In recent decades, several pathogens have been reported to be involved in the development of CD, but only Escherichia coli (E. coli) and Mycobacterium avium paratubercolosis (MAP) have aroused interest due to their strong association with CD pathogenesis. Several meta-analyses have been published concerning antibiotic treatment for CD patients, but randomized trials testing antibiotic treatment against E. coli and MAP have not shown prolonged benefits and have generated conflicting results; several questions are still unresolved regarding trial design, antibiotic dosing, the formulation used, the treatment course, and the outcome measures. In this paper, we provide an overview and update of the trials testing antibiotic treatment for active CD patients, taking into account the role of pathogens, the mechanisms by which different antibiotics act on harmful pathogens, and antibiotic resistance. Finally, we also present new lines of study for the future regarding the use of antibiotics to treat patients with active CD.

VARIOUS ADHERENT-INVASIVE E. COLI (AIEC) AND NON-AIEC STRAINS ISOLATED FROM CROHN’S DISEASE PATIENTS GROW DIFFERENTLY WITH RUMINOCOCCUS GNAVUS PRE-DIGESTED MUCUS AND R. GNAVUS-RELEASED PRE-DIGESTED ILEAL AND COLONIC MUCUS MONOSACCHARIDES

Abstract BACKGROUND Mucus-digesting Ruminococcus gnavus (R. gnavus), adherent-invasive E. coli (AIEC), and hydrogen sulfide (H2S) are enriched in active Crohn’s disease (CD) patients compared to healthy subjects. Dual colonization of R. gnavus and E. coli LF82 in ex-germ-free mice enhanced distal colitis and H2S production in cecal contents. R. gnavus pre-digestion of mucus enhanced the ileal CD isolate AIEC LF82 growth and H2S production in vitro. H2S enhanced LF82 adhesion and invasion both in vitro and in vivo along with related LF82 adhesion gene expression and Caco-2 cell expression of CEACAM6, a receptor for AIEC ligand FimH. Interactions between other CD-derived AIEC/non-AIEC and R. gnavus are unknown. HYPOTHESIS Different AIEC and non-AIEC may grow and produce H2S differently using mucus digested by R. gnavus, which releases mucus-derived monosaccharides and sulfur substrates. METHODS We studied CD-derived clinical isolates of AIEC 541-15 (phylotype A), 541-1 (B1), LF82 and NRG857c (B2) and non-AIEC T75 (A) and lab strain K12 (A). M9 minimal media was supplemented with porcine gastric mucin (PGM), ileal (MIM) and colonic (MCoM) mucus isolated from germ-free mice. We measured growth kinetics and H2S production by these AIEC and non-AIEC following culture with sterile supernatants of each mucin/mucus media precultured with or without R. gnavus, monosaccharides obtained by R. gnavus digestion of mucus, and several sulfur substrates in the gut added to M9 minimal media. RESULTS AIEC, especially LF82 (B2), grew better with ileal mucus aerobically and, to a lesser extent, anaerobically than non-AIEC strains, with even greater AIEC growth with R. gnavus pre-digested mucus (Fig.1). AIEC produced more H2S with R. gnavus-precultured mucus than with mucus alone. R. gnavus digestion of PGM released mucus monosaccharides (Fig.2A). AIEC strains grew differently with each monosaccharide constituent of R. gnavus pre-digested PGM. AIEC grew better than non-AIEC with each monosaccharide in aerobic conditions, but AIEC (B2) grew better than others in all monosaccharides in anaerobic conditions (Fig.2B). Amongst mucus-relevant sulfur substrates, L-cysteine was the only substrate to enhance E. coli H2S production by all AIEC and non-AIEC strains. All mucus-relevant sulfur substrates supported R. gnavus survival for 24 hrs, while H2S sustained R. gnavus for 48 hrs in minimum media. CONCLUSIONS AIEC grew better and produced more H2S with R. gnavus pre-digested mucus suggesting that co-existence of AIEC with R. gnavus mutually support each other and may explain why they are often observed together in active CD patients. In addition, enhanced AIEC growth with ileal vs. colonic mucus may explain why AIEC are frequently isolated from ileal CD patients. AIEC phylotype growth differences with mucus substrates may explain their persistence in the ileal mucosa. Figure 1 Figure 2

ORGANIC ANION TRANSPORTER POLYPEPTIDE (OATP) 3A1 AMELIORATES INTESTINAL MUCOSAL DAMAGE IN INFLAMMATORY BOWEL DISEASE

Abstract BACKGROUND Inflammatory bowel disease (IBD) is a chronic condition characterised by disruption of the colonic mucosal barrier. OATP3A1/SLCO3A1 is a bile acid efflux transporter, alleviating cholestasis-associated liver injury. However, the functional role and regulational mechanism of intestinal OATP3A1 in IBD remain unclear. METHODS The expression and correlation of SLCO3A1 were investigated in the public datasets with IBD patients. Intestinal epithelial cell-specific Slco3a1 knockout (Slco3a1ΔIEC) mice were generated and fed with 4% DSS for functional studies. RESULTS Intestinal SLCO3A1 expression was significantly elevated in the ulcerative colitis (UC) and Crohn's disease (CD) patients, and positively correlated with TNFα, IL1β and MADCAM1. Compared with Slco3a1flox/flox littermates administrated by DSS, Slco3a1ΔIEC mice exhibited exacerbated colitis, characterized by more severe weight loss, enhanced colon shortening and spleen swelling. Interestingly, intestine histology assessments revealed that epithelial Oatp3a1 ablation significantly aggravated extensive disruption of the mucosal epithelium and inflammatory infiltration. The intestinal mucosal barrier function of Slco3a1ΔIEC mice was more severely damaged, as assessed by detecting serum permeated FITC-dextran. Expression of tight junction-associated proteins was decreased in Slco3a1ΔIEC mice. CONCLUSION Our data showed that intestinal OATP3A1 expression was markedly upregulated and exerted a protective role in inflammatory bowel disease. Overexpression of intestinal OATP3A1 may hold potential as a novel approach to alleviate intestinal inflammation- associated mucosal damage. Figure 1 SLCO3A1 mRNA levels in the intestinal tissues of IBD patients and generation of Slco3a1ΔIECmice. (A) SLCO3A1 mRNA expression in patients with active UC or active CD and matched controls, revealed by analyzing databases of RNA-Seq data. (B and C) Pearson’s correlation analysis between SLCO3A1 expression and TNF-α, IL1β, or MADCAM1 in colon biopsy samples from active UC (n = 74) and CD (n = 52) patients. Data were collected from GEO database GSE75214. (D) Schematic diagram of Slco3a1ΔIEC mice. (E) Genotyping of Slco3a1ΔIEC mice using genomic DNA extracted from mice tails. (F) Western blot confirmed the intestine epithelia ablation of OATP3A1 in Slco3a1ΔIEC mice. Figure 2 Effects of intestinal epithelia-specific ablation of OATP3A1 on colitis and mucosal damage in a 4% DSS treatment mouse model of IBD. (A, B) Body weight loss and spleen weight were measured from Slco3a1flox/flox or Slco3a1ΔIEC mice. (C) Serum FITC-dextran level was detected by fluorescence spectrophotometer. (D) Gross morphology images of the colon, and colon length were measured. (E) Representative images of H&amp;E-stained colons, and histopathology analysis of colitis were performed. (F) Immunoblots of colonic lysates on Zo-1, Occludin or Claudin-1(n = 4 for each group). **P &amp;lt; 0.01; ***P &amp;lt; 0.001. n = 5 for Slco3a1flox/flox group; n =6 for Slco3a1ΔIEC group treated with DSS.

P902 Subcutaneous infliximab (CT-P13 SC) as maintenance therapy for Crohn’s disease: 2 years results of the LIBERTY-CD study

Abstract Background CT-P13 subcutaneous (SC) infliximab formulation showed superiority over placebo as maintenance therapy at Week 54 in Crohn’s disease (CD)1 and ulcerative colitis2. The LIBERTY-CD study1 included an extension phase up to Week 102, the results, of which, are reported. Methods Patients who completed the maintenance phase up to Week 54 and, in the opinion of the investigator, would benefit from continued treatment could continue the open-label extension phase from Week 56 to Week 102 and received CT P13 SC 120 mg regardless of the previous assigned arm of maintenance phase. Patients who had received the adjusted dose of CT-P13 SC 240 mg during the maintenance phase continued receiving the same doses in the extension phase. At Week 54 and Week 102, clinical remission, clinical response, endoscopic remission, endoscopic response, clinical remission (alternative definition) and corticosteroid-free remission were assessed for patients who were treated CT-P13 SC during the extension phase (Figure 1.A) or who were treated CT-P13 SC during the extension phase and had valid efficacy results at the visit of interest (Figure 1.B). Patients with dose adjustment to CT-P13 SC 240 mg prior to Week 54 were considered as non-remitter/non-responder. Safety was evaluated through the extension phase. Results A total of 180 patients in the CT-P13 SC arm (assigned arm at the maintenance phase) entered into the extension phase. Overall, 85.6% (154/180) completed extension phase. Compared to the Week 54 results, efficacy results in the CT-P13 SC arm based on the non-responder imputation for missing or invalid data (i.e., patients who had missing or invalid data were considered as non-remitter/non-responder) were generally maintained in clinical remission, clinical response, endoscopic remission, endoscopic response, clinical remission (alternative definition), and corticosteroid-free remission at Week 102 (Figure 1.A). The efficacy results based on the no imputation for missing or invalid data (i.e., observed data) at Week 54 and Week 102 were similar (Figure 1.B). There was no new safety issue reported during the extension phase (Table 1). No death was reported during the extension phase. Conclusion Efficacy of CT-P13 SC was maintained through the extension phase. No new safety concerns were observed during the extension phase. These results show that CT-P13 SC provides both a long-term clinical benefit and safety with the convenience of SC administration for moderately to severely active CD patients. [1] Colombel et al., Journal of Crohn's and Colitis, 2023. [2] Sands et al., Journal of Crohn's and Colitis, 2023.

P070 The influence of Crohn’s disease-derived blood plasma upon anabolic signaling responses to leucine stimulation in skeletal muscle cells in vitro

Abstract Background Many Crohn’s Disease (CD) patients have low muscle mass and function (sarcopenia), yet the precise drivers of this pathophysiology are unclear. Positive muscle protein balance is driven by essential amino acids (EAA) that stimulate muscle protein synthesis (MPS), with the EAA leucine (L) playing a key role. However, if circulating factors in CD impact muscle anabolic responses to feeding remain unclear. Our aims were to use plasma from healthy human volunteers (HV) and active CD patients to investigate the impact on anabolic signaling and responses to feeding. Methods HV were 32 ± 4 y with a BMI 24 ± 1 and CD 26 ± 3 y with a BMI 23 ± 1 disease duration 5 ± 1 y faecal calprotectin 720 ± 12 ug/g. C2C12 myotubes were treated with 4 conditions of media conditioned with 5% plasma from HV or CD, in addition to being treated ± 5mM L for 4 hrs. Protein content was quantified via nanodrop and muscle anabolic signaling measured via immunoblotting for p-mTORC1 (Ser2448), p-4E-BP1 (Thr37/46) and p-P70S6K1 (Thr389). Results Immunoblotting revealed no difference in mTORC1 phosphorylation between HV and CD (HV:18.9 ± 2.7 AU, CD: 19.9 ± 3.2 AU), with no change in response to L treatment (HV:18.0 ± 2.4 AU, CD: 16.6 ± 2.3 AU). There was no difference in P70S6K1 phosphorylation between HV and CD (HV: 33.7 ± 3.2 AU, CD: 28.0 ± 4.7 AU) with both groups showing significant increases in phosphorylation with L treatment (HV: 56.4 ± 4.2 AU (P&amp;lt;0.05), CD: 54.5 ± 9.2 AU (P&amp;lt;0.001)). There was no difference in 4EBP1 phosphorylation between HV and CD (HV: 49.8 ± 6.4 AU, CD: 64.6 ± 7.5 AU) with only HV showing a significant increase in phosphorylation with L (HV: 105.5 ± 8.7 AU (P&amp;lt;0.0001), CD: 47.8 ± 5.3 AU). There was difference in total protein concentration between HV and CD, or with L treatment. Conclusion We found CD derived blood plasma did not impact the leucine stimulated increase in P70S6K1 phosphorylation but did result in blunted phosphorylation of 4EBP1. These disparities in anabolic signaling indicate that systemic factors in CD may impact muscle anabolic responses to feeding. Yet, the relationship between anabolic markers and rates of MPS remains complex.

Association of Periodontal Disease with Activity of Crohn's Disease.

Crohn's disease (CD) is a chronic inflammatory granulomatous disease that can affect the entire gastrointestinal tract. It is characterized by various extraintestinal manifestations (EIMs), of which oral manifestations (OMs) are often possible. One of the possible OMs is periodontal disease (PD), a chronic inflammatory condition of the supporting tissues of the teeth. This study aimed to show the existence of a mutual relationship between the clinical activity of PD and the clinical and endoscopic activity of CD. One clinical and two endoscopic indexes were used for the assessment of CD activity and clinical attachment loss (CAL), bleeding on probing (BOP), pocket probing depth (PPD), and radiographic bone loss (RBL) in a dental panoramic tomogram to assess PD in CD patients. A total of 38 patients underwent the entire study process, of which 20 patients had CD and 18 patients had CD and PD. Considering all CD activity scores, there were 26 patients with active disease; half of them had PD, and 85.7% of operated patients had active CD. The values of CAL, PPD, BOP, and RBL were higher in active CD patients than those in remission, except for BOP when comparing to the CDAI score, which was higher in those in remission of CD. The results of this study indicate that there is a connection between the activity of CD and worse conditions of the supporting tissues of the gums in the oral cavity, so it is important to keep in mind the necessity of referring patients with CD to a dentist for timely and adequate therapeutic measures.

Inflammatory mesenteric fat detected by Intestinal ultrasound is correlated with poor long-term clinical outcomes in patients with Crohn's disease

BackgroundData on the correlation between inflammatory mesenteric fat (i-fat), detected by intestinal ultrasound (IUS), and the prognosis of Crohn's disease (CD) remains limited. AimsTo investigate the impact of IUS-detected i-fat on long-term clinical outcomes. MethodsWe retrospectively enrolled 171 active CD patients who initiated infliximab. Clinical remission (CR), mucosal healing (MH) and transmural healing (TH) were assessed at week-14 and 1 year. ResultsBaseline i-fat was detected in 107 patients, while 64 without i-fat. At week-14 and 1 year, patients with i-fat showed lower rates of CR (61.7% vs. 87.5%; 62.3% vs. 86.7%), MH (20.6% vs. 46.9%; 38.6% vs. 65.0%) and TH (10.3% vs. 31.3%; 21.6% vs. 51.7%), compared to those without (all p<0.01). Multivariable analysis revealed that baseline i-fat was a negative predictor for CR (OR=0.212) and MH (OR=0.425) at week-14, and CR (OR=0.340) and TH (OR=0.364) at 1 year (all p<0.05). At week-14, 56 patients with baseline i-fat recovered to without i-fat. Patients with i-fat recovery had higher rates of CR (86.8% vs. 23.1%), MH (58.5% vs. 7.7%) and TH (34.0% vs. 2.6%) at 1 year than those with i-fat at week-14 (all p<0.001). ConclusionIUS-detected i-fat correlated poor long-term clinical outcomes in CD with infliximab.

Fecal miR-223 is a noninvasive biomarker for estimating Crohn's disease activity.

MicroRNA-223 (miR-223) has emerged as a promising noninvasive biomarker for Crohn's disease (CD). However, it is unclear which tissue derived miRNA-223 can more accurately estimate CD disease activity. To collect serum, terminal ileal mucosa biopsy and fecal samples from CD patients and healthy controls. The CD Activity Index (CDAI) score, Montreal classification, maintenance medicines, peripheral blood inflammatory markers, fecal calprotectin (FC) and the Simple Endoscopic Score for CD (SES-CD) were recorded. To compare the expression of miR-223 in the serum, intestinal tissue, and feces. MiR-223 expression levels in the serum, intestinal tissue and feces of CD patients were significantly higher than those of controls. The level of miR-223 in the serum, intestinal tissue and feces increased significantly in active CD patients compared with that in inactive CD patients. The levels of serum, intestinal tissue and fecal miR-223 were correlated with the CDAI. Serum miR-223 was also correlated with C-reactive protein (CRP) and IL-6, tissue miR-223 correlated with IL-6 and FC, and fecal miR-223 correlated with FC. In terms of the association with FC, fecal miR-223 had a higher Spearman r value than tissue miR-223. The area under the curve (AUC) values of serum, tissue and fecal miR-223 to diagnose CD were similar to those of CRP and FC (AUC > 0.8). The AUC values of tissue and fecal miR-223 to evaluate CD disease activity were 0.832 and 0.818, respectively, and were higher than serum miR-223, CRP and FC. Fecal miR-223 had a higher specificity of 92.3%. Fecal miR-223 might be a novel, noninvasive biomarker for estimating the disease activity of CD patients.

Amino acid profiles, disease activity, and protein intake in adult patients with Crohn's disease.

Crohn's disease (CD) is an immune-mediated inflammatory disorder of the gastrointestinal tract with a relapsing-remitting course. Amino acids (AAs) may play critical roles in the intestinal manifestations of disease, due to their involvement in many metabolic and immune functions. The present study aimed to explore serum AA concentrations in adult patients with CD, looking into their variations due to disease activity, surgery and protein content of diet. Eventually, the link between AAs and inflammatory markers was also assessed. Consecutive adult patients aged 18-65 years with diagnosis of CD were recruited. All participants underwent anthropometry and were instructed to fill in a 3-day food record to assess protein intake. Disease activity was clinically defined using the Crohn's Disease Activity Index (CDAI), while blood samples were taken to analyze serum AA profile and inflammatory markers. A total of 103 patients with CD (61 men and 42 women; age:39.9 ± 13.9 years, BMI: 23.4 ± 3.51 kg/m2) were included. Tryptophan levels were found to be remarkably decreased in most subjects, unrelated to disease activity. On the contrary, concentration of lysine, leucine, valine and glutamine decreased in active versus quiescent CD patients, while aspartic acid, glutamate and glycine increased. The latter AAs were also directly correlated with CDAI and serum interleukin (IL)- 1β concentration. Considering the total protein intake, expressed as g/kg/body weight, we observed a reduction in some essential AAs in patients with unmet protein requirements compared to patients who met the recommendation. In conclusion, specific AAs varied according to disease activity and protein intake, adjusted to body weight and disease status. Glu and Asp concentrations raised with increasing IL-1β. However, extensive research is needed to understand the mechanisms underpinning the link between variation in serum AAs, disease activity and protein intake in patients with CD.

Platelet-lymphocyte ratio and lymphocyte-monocyte ratio in inflammatory bowel disease and disease activity: A systematic review and meta-analysis.

This review aimed to examine if the platelet-lymphocyte ratio and lymphocyte-monocyte ratio can be useful in determining disease activity in patients with inflammatory bowel disease. PubMed, CENTRAL, Scopus, Embase, and Web of Science were searched for studies published up to 9 January 2023. Platelet-lymphocyte ratio and lymphocyte-monocyte ratio values from active and remission inflammatory bowel disease cases were compared to generate a mean difference (MD). Nine studies were included. Meta-analysis showed that inflammatory bowel disease patients with active disease had significantly higher values of platelet-lymphocyte ratio as compared to those in remission (MD: 63.46 95% CI: 35.74, 91.17, I2 = 89%). The values of platelet-lymphocyte ratio were significantly higher in both active ulcerative colitis and Crohn's disease patients. Meta-analysis also showed that lymphocyte-monocyte ratio values were significantly lower in active inflammatory bowel disease patients as compared to those under remission (MD: -1.28 95% CI: -1.42, -1.14, I2 = 4%). Lymphocyte-monocyte ratio values were significantly lower in both ulcerative colitis and Crohn's disease patients with active disease. Platelet-lymphocyte ratio and lymphocyte-monocyte ratio can be useful blood-based markers in differentiating active disease in inflammatory bowel disease patients. Active cases of ulcerative colitis and Crohn's disease have high platelet-lymphocyte ratio and low lymphocyte-monocyte ratio as compared to those in remission. Further studies with a larger sample size are needed to strengthen conclusions.

Changes in the gut mycobiome in pediatric patients in relation to the clinical activity of Crohn's disease

Numerous studies have shown that in Crohn's disease (CD), the gut microbiota is of great importance in the induction and maintenance of inflammation in the gastrointestinal tract. Until recently, studies have focused almost exclusively on bacteria in the gut. Lately, more attention has been paid to the role of intestinal fungi. To study the gut mycobiome analysis of pediatric patients with CD (in different stages of disease activity) compared to healthy children. Fecal samples were collected from patients: With active, newly diagnosed CD (n = 50); active but previously diagnosed and treated CD (n = 16); non-active CD and who were in clinical remission (n = 39) and from healthy volunteers (n = 40). Fungal DNA was isolated from the samples. Next, next generation sequencing (MiSeq, Illumina) was performed. The composition of mycobiota was correlated with clinical and blood parameters. Candida spp. were overrepresented in CD patients, while in the control group, the most abundant genus was Saccharomyces. In CD patients, the percentage of Malassezia was almost twice that of the control (P < 0.05). In active CD patients, we documented a higher abundance of Debaryomyces hansenii (D. hansenii) compared to the non-active CD and control (P < 0.05) groups. Moreover, statistically significant changes in the abundance of Mycosphaerella, Rhodotorula, and Microidium were observed. The analyses at the species level and linear discriminant analysis showed that in each group it was possible to distinguish a specific species characteristic of a given patient population. Moreover, we have documented statistically significant correlations between: D. hansenii and patient age (negative); C. zeylanoides and patient age (positive); C. dubliniensis and calprotectin (positive); C. sake and calprotectin (positive); and C. tropicalis and pediatric CD activity index (PCDAI) (positive). Mycobiome changes in CD patients, and the positive correlation of some species with calprotectin or PCDAI, give strong evidence that fungi may be of key importance in the development of CD.

Tissue and Circulating MicroRNA-31, MicroRNA-200b, and MicroRNA-200c Reflects Disease Activity in Crohn‘s Disease Patients: Results from the BIOMIR Study

MicroRNAs (miR) have altered expression in multiple autoimmune disorders including inflammatory bowel disease. The aim of the study was to assess the tissue and circulating miR-31, miR-200b, and miR-200c expression levels as potential biomarkers for intestinal disease activity in patients with Crohn's disease (CD). The study included 45 patients with histopathological confirmed CD and active disease (defined as fecal calprotectin >50 μg/g and Simple Endoscopic Score (SES) of CD >3), and 21 subjects as controls for the validation cohort. Demographic and clinical data, biomarkers (fecal calprotectin), endoscopy data, the expression levels of miR-31, miR-200b, and miR-200c in tissue and serum were assessed (by RT-PCR). Receiver operating characteristic analysis was performed to assess the miR-31, miR-200b, and miR-200c expression levels as potential biomarkers for active CD. Mean fecal calprotectin was 1540±890 μg/g. Mean SES-CD was 8.9±4.2. Tissue and circulating miR- 31 were significantly correlated with fecal calprotectin (r=0.81, r=0.83, p<0.01) and with SES-CD (r=0.82, r=0.79, p<0.01). The expression level of miR-31 was significantly upregulated in CD tissue cases compared to the control tissue samples (6.24±1.57 vs. 3.70±1.44; p <0.01). Similarly, serum miR-31 expression levels in CD patients were significantly upregulated compared to the control serum samples (0.78±0.42 vs. -2.07±1.00; p<0.01). The expression levels of tissue miR-200b and miR-200c were significantly upregulated in CD tissue cases compared to the control tissue samples (-5.25±0.93 vs. -4.69±0.80, p=0.03 for miR-200b, and -0.86±0.96 vs. 0.39±0.66, p<0.01 for miR-200c). Similarly, serum miR-200b and miR-200c expression levels in CD patients were significantly upregulated compared to the control serum samples (p < 0.05). Receiver operating characteristic analysis revealed that the expression levels of the selected miRNAs could help to discriminate active CD patients from healthy controls with very good specificity and sensitivity. Tissue and circulating miR-31, miR-200b, and miR-200c reflect disease activity in CD patients and can be used as biomarkers for active disease.

A17 EVIDENCE OF PROTEASE-MEDIATED PRO-NOCICEPTIVE EFFECTS OF FECAL SUPERNATANTS FROM CROHN'S DISEASE PATIENTS

Abstract Background Abdominal pain is a debilitating symptom of Crohn’s disease (CD). Despite the current treatment options for this disease, abdominal pain is an unresolved problem that commonly persists in the absence of active inflammation. This suggests that something other than inflammation is driving the pain during the quiescent phase. We have previously reported that microbial proteases can directly modulate the excitability of dorsal root ganglia (DRG) neurons, many of which are pain-sensing. We hypothesize that luminal proteases of CD patients are contributing to their abdominal pain. Purpose Determine whether luminal mediators in CD fecal samples induce changes in pain signalling. Method The effects of patient (active CD [n = 3] and healthy volunteer (HV) [n = 3]) fecal supernatant (FS) samples on pain-sensing neurons were assessed using ex-vivo single unit afferent nerve recordings from mouse colons. Each sample was tested in colonic preparations from a least 5 mice. To further examine cellular mechanisms, DRG neurons were isolated and incubated overnight in media containing CD FS or HV FS media. Changes in neuronal excitability were recorded by determining the rheobase (lower rheobase=increased excitability) using patch clamp recordings (n ≥ 9 DRG neurons/group). Protease inhibitors were applied in both bioassays to determine whether these inhibited the excitatory effect of FS. Lastly, total proteolytic activity in the CD and HV fecal samples was calculated using a casein colorimetric protease detection assay. Result(s) FS from HV had no effect on afferent nerve excitability (p = 0.8920). FS from active CD patients increased action potential discharge from colonic afferent nerves by 85% (p&amp;lt;0.0001) and selectively increased the activation of high-threshold units, which are putative nociceptors, by 44% (p=0.0074). A protease inhibitor cocktail (1:1000) and protease-activated receptor (PAR)-2 antagonist GB83 (10µM) both blocked the excitatory effects of CD FS (p&amp;lt;0.05). Overnight incubation with CD FS also had an excitatory effect on DRG neurons compared to HV FS (rheobase decreased by 46%, p&amp;lt;0.05). The effect of CD FS was blocked by GB83 (10µM) (p&amp;lt;0.001) and a serine protease inhibitor (FUT175; 100µM) (p&amp;lt;0.05) independently, but the activity was not blocked by E64 (30nM) a cysteine protease inhibitor. A 200-fold increase (p&amp;lt;0.0001) in total proteolytic activity was found in CD FS compared to HV FS. Conclusion(s) Luminal serine proteases, but not cysteine proteases, appear to be driving nociceptive signalling in CD patients. This provides insight into the generation of pain in CD patients and may be a potential target to mitigate this action. Further research is required to elucidate whether these pro-nociceptive proteases are of bacterial or host origin and their effects in the quiescent phase. Disclosure of Interest None Declared

Repeated and multiple fecal microbiota transplantations plus partial enteral nutrition as the first-line treatment in active pediatric Crohn's disease.

Most studies have reported fecal microbiota transplantation (FMT) as an effective secondary option for Crohn's disease (CD). However, there is little data on FMT as a first-line treatment for CD. In our study we explore the rates of clinical and endoscopic remission and mucosal healing after FMT plus partial enteral nutrition (PEN), as a first-line treatment for active CD in children. We retrospectively enrolled pediatric CD patients who underwent PEN or PEN plus FMT treatment at diagnosis from November 2016 to July 2019 at the Pediatric Department, Tongji Hospital. The two groups were defined as FMT group (repeated and multiple doses of FMT plus PEN) or PEN group (PEN alone). All the patients received PEN intervention. At baseline and week 8- 10, the FMT group was administered multiple doses of FMT to help induce and maintain remission. All patients were evaluated at week 8- 10 and 18-22 via clinical and relevant laboratory parameters and endoscopic results. The clinical and endoscopic remission and mucosal healing rates were compared between the two groups at different time points after the therapy. Twenty-five newly diagnosed active CD patients were included in the study, containing 7 females and 18 males with a median age of 11. 1 ± 2.3 years. 13 and 12 patients were assigned to the PEN and FMT groups, respectively. At week 8-10, clinical remission was obtained in 83.3% and 53.8% of the FMT and PEN groups, respectively (p=0.202). The endoscopic remission rates were 72.7% for FMT and 25.0% for PEN (p=0.039), whereas the mucosal healing rates were 27.2% for FMT and 0% for PEN (p=0.093). At week 18-22, clinical remission was achieved in 72.7% and 20.0% of patients in the FMT and PEN groups, respectively (p=0.03). Theendoscopic remission rates were 66.6% and 12.5% in the FMT and PEN groups, respectively (p=0.05), whereas the mucosal healing rates were 55.5% and 0% in FMT and PEN groups, respectively (p=0.029). This study demonstrate that FMT plus PEN can be used as a first-line treatment for active CD in children.

P105 Epithelial microRNA signatures as potential biomarkers in Crohn’s disease related to clinical and endoscopic activity

Abstract Background Emerging evidence suggests that epithelial cell-derived microRNAs (miRNA) are involved in the pathogenesis of inflammatory bowel disease; however, as of now specific implications in the real clinical practice, especially in relation to biologics use are yet far-fetched. Therefore, we tried to investigate specific epithelial cell derived miRNA signatures related to clinical and endoscopic activity in Crohn’s disease (CD) patients. Methods We prospectively collected terminal ileum tissue samples via ileocolonoscopy from healthy control (n=12), CD patients in remission (n=32) and active CD patients (n=36). CD remission was defined as clinical remission of Crohn's disease activity index (CDAI) &amp;lt;150 and achievement of endoscopic mucosal healing. Both inflamed and non-inflamed lesions were sampled in the active CD patients. Clinical information, medication use, chemistry data were measured within a week from the tissue sample date. miRNA levels were measured by small-RNA sequencing and qRT-PCR. Diagnostic ability of specific miRNA found were evaluated by receiver operating characteristic (ROC) curve analysis. Results The study cohort was followed up until January 2022. Mean follow-up period of the prospective CD cohort was 13.06 months. In comparing to the healthy control, CD patients in remission and active state revealed specific miRNA profiles in small-RNA sequencing. Through RT-PCR validation, we found that the expression levels of miR-141-3p, miR-338-3p, miR-378a-3p, and miR-200b-3p were significantly decreased, while miR-125b-5p, miR-29b-3p and miR-155-5p were significantly increased in the inflamed tissue of active CD patients. Moreover, in case of active CD patients, expressions of miR-150-5p, miR-200b-3p and miR-155-5p were significantly down-regulated in those using biologics, compared with biologics naïve patients. This may suggest that these miRNAs were not only as biomarkers of CD patients, but also as biomarkers related to inflammation and biologics response. ROC curve analysis suggested miRNAs with different diagnostic activity related to both clinical disease activity and endoscopic inflammation status. MiR-338-3p, miR-141-3p and miR-378a-3p demonstrated area under curve of greater than 0.9 in predicting active CD patients. Conclusion We report specific miRNA biomarkers identifying CD and its disease inflammation activity with relation to biologics use, suggesting potential treatment target in CD pathogenesis. These miRNA signatures could also be of potential clinical use in positioning biologics, which we intend to explore in the near future.

DOP86 Subcutaneous infliximab (CT-P13 SC) as maintenance therapy for Crohn’s disease: A phase 3, randomised, placebo-controlled study (LIBERTY-CD).

Abstract Background CT-P13 subcutaneous (SC) infliximab formulation showed comparable efficacy and safety with CT-P13 intravenous (IV) infliximab in inflammatory bowel disease (IBD)1 and rheumatoid arthritis2. This study aimed to demonstrate the superiority of CT-P13 SC over placebo as maintenance therapy after induction therapy of CT-P13 IV in patient with Crohn’s disease (CD). Methods Moderately to severely active CD patients with Crohn’s disease activity index (CDAI) score 220 to 450 and simplified endoscopic activity score for Crohn’s disease (SES-CD) of ≥6 points for ileal-colonic CD or ≥4 points including ulcer score from at least 1 segment for ileal CD or colonic CD were enrolled LIBERTY-CD study (NCT03945019) and treated with open-label CT-P13 IV 5 mg/kg at Weeks 0, 2 and 6 as induction therapy. At Week 10, patients who had a clinical response were randomised (2:1) to receive either CT-P13 SC 120 mg (CT-P13 SC) or placebo every 2 weeks up to Week 54. At Week 54, clinical remission and endoscopic response were assessed as co-primary endpoints. Clinical response, clinical remission (alternative definition), endoscopic remission, and corticosteroid-free remission were assessed at Week 54 as key secondary endpoint. Safety was evaluated up to Week 54. Results A total of 396 patients were enrolled and 343 patients (86.6%) were randomised (231 in CT-P13 SC arm and 112 in placebo arm) at Week 10. At Week 54, the clinical remission rate was greater in CT-P13 SC arm than placebo arm (62.3% and 32.1% respectively, with P &amp;lt;0.0001). The endoscopic response rate was also greater in CT-P13 arm than placebo arm (51.1% and 17.9% respectively, with P &amp;lt;0.0001). CT-P13 SC also had significantly greater efficacy on key secondary endpoints results compared to placebo arm (Table 1). Safety profiles were generally comparable between CT-P13 SC and placebo arms, but a single death was reported during the maintenance phase (Table 2). Conclusion CT-P13 SC was more effective than placebo in clinical remission, endoscopic response, clinical response, clinical remission (alternative definition), endoscopic remission, and corticosteroid-free remission at Week 54. No new safety concerns were found during treatment of CT-P13 SC. These results demonstrate that maintenance therapy with CT-P13 SC provides both a robust clinical benefit and the convenience of SC administration to moderately to severely active CD patients. [1] Schreiber et al., 2021. Gastroenterology 2021;160:2340–23 [2] Westhovens et al., 2020. Rheumatology 2020;00:1