Biomarkers In Inflammatory Bowel Disease Research Articles

Novel Biomarkers for Inflammatory Bowel Disease and Colorectal Cancer: An Interplay between Metabolic Dysregulation and Excessive Inflammation.

Persistent inflammation can trigger altered epigenetic, inflammatory, and bioenergetic states. Inflammatory bowel disease (IBD) is an idiopathic disease characterized by chronic inflammation of the gastrointestinal tract, with evidence of subsequent metabolic syndrome disorder. Studies have demonstrated that as many as 42% of patients with ulcerative colitis (UC) who are found to have high-grade dysplasia, either already had colorectal cancer (CRC) or develop it within a short time. The presence of low-grade dysplasia is also predictive of CRC. Many signaling pathways are shared among IBD and CRC, including cell survival, cell proliferation, angiogenesis, and inflammatory signaling pathways. Current IBD therapeutics target a small subset of molecular drivers of IBD, with many focused on the inflammatory aspect of the pathways. Thus, there is a great need to identify biomarkers of both IBD and CRC, that can be predictive of therapeutic efficacy, disease severity, and predisposition to CRC. In this study, we explored the changes in biomarkers specific for inflammatory, metabolic, and proliferative pathways, to help determine the relevance to both IBD and CRC. Our analysis demonstrated, for the first time in IBD, the loss of the tumor suppressor protein Ras associated family protein 1A (RASSF1A), via epigenetic changes, the hyperactivation of the obligate kinase of the NOD2 pathogen recognition receptor (receptor interacting protein kinase 2 [RIPK2]), the loss of activation of the metabolic kinase, AMP activated protein kinase (AMPKα1), and, lastly, the activation of the transcription factor and kinase Yes associated protein (YAP) kinase, that is involved in proliferation of cells. The expression and activation status of these four elements are mirrored in IBD, CRC, and IBD-CRC patients and, importantly, in matched blood and biopsy samples. The latter would suggest that biomarker analysis can be performed non-invasively, to understand IBD and CRC, without the need for invasive and costly endoscopic analysis. This study, for the first time, illustrates the need to understand IBD or CRC beyond an inflammatory perspective and the value of therapeutics directed to reset altered proliferative and metabolic states within the colon. The use of such therapeutics may truly drive patients into remission.

Immunomodulatory Role of Neuropeptide Y in Intestinal Inflammation

Neuropeptide Y (NPY) is a 36-amino acid peptide found in the brain, autonomic nervous system, and different peripheral tissues, including the gastrointestinal (GI) tract. Dysfunction of the NPY or NPY system has been implicated in various tumor microenvironments and cardiovascular and GI disorders, such as inflammatory bowel disease (IBD). IBD, including Crohn’s disease (CD) and ulcerative colitis (UC), is a major health concern due to its increasing incidence globally. Emerging evidence has demonstrated that NPY also acts as a potent immunomodulator by linking the nervous and immune systems. NPY plays an important role in immunopathology during intestinal inflammation. This paper discusses the potential role of NPY as a valuable biomarker for IBD due to its consistent upregulation in both in vivo and clinical studies. Consequently, it confirms the pro-inflammatory effects of NPY, providing a rational basis for targeting NPY signaling as a therapeutic strategy.

P879 Clinical significance of plasma interleukin-22 as a biomarker of inflammation in patients with Crohn’s disease and ulcerative colitis

Abstract Background IL-22 is a key cytokine in the pathogenesis of inflammatory bowel disease (IBD). While evidence underpinning its central role as a biomarker of pathway activation, diagnosis, severity and activity for IBD has been accumulating, little is known about its application as a biomarker in IBD in real-world practice. Here, we characterize for the first time the relationship between IL-22 plasma concentrations and the clinical characteristics of a large, real-world population of patients with IBD. Methods This is a descriptive analysis of patients in the Study of a Prospective Adult Research Cohort with IBD (SPARC IBD) obtained from the IBD Plexus registry of the Crohn’s & Colitis Foundation in the United States. The SPARC registry includes patients with a diagnosis of Crohn’s disease (CD) or ulcerative colitis (UC). This study evaluated baseline data collected within ± 30 days from consent date. Assessments included demographics, clinical characteristics and IL-22 plasma concentrations. Disease severity was assessed using short CD Activity Index (sCDAI; scores <150 define remission, 150–219 mild activity, ≥220 moderate-severe activity) or 6-point UC Disease Activity Index (UCDAI; scores ≤1 define remission, 2–3 mild activity, ≥4 moderate-severe activity) disease severity categories. Results A total of 2667 patients with CD and 1326 patients with UC were eligible for inclusion in the study. For patients with CD, median age was 39 years, 57% were female and median disease duration was 13 years (Table 1). For patients with UC, median age was 40 years, 51% were female and median disease duration was 9 years (Table 1). In total, 1604 patients with CD and 836 patients with UC had valid IL-22 samples at baseline, of which 33% and 25%, respectively, were above the lower limit of quantification (LLOQ; 7.8 pg/mL). There was a trend toward fewer patients with IL-22 levels below the LLOQ among patients with high disease severity compared with those with lower disease severity both in patients with CD and those with UC (Figure 1). Additionally, there was an increase in the percentage of patients with IL-22 levels greater than the third quartile (overall Q3 = 10.8 pg/mL in CD, and = 7.9 pg/mL in UC) with increased disease severity (Figure 2). Comparison of subgroups of patients with low and medium/high IL-22 levels showed a consistent pattern with fewer patients in remission and more moderate-severe patients in the medium/high IL-22 group than in the low IL-22 group (Table 2). Conclusion Higher IL-22 levels tended to be associated with higher disease activity in this real-world population of IBD patients.

P154 A novel serum protein signature as biomarker for Inflammatory Bowel Disease: A diagnostic performance and prediction modelling study using data from two independent inception cohorts

Abstract Background The diagnosis of inflammatory bowel disease (IBD) is often delayed since existing biomarkers in blood are imprecise and faecal tests are poorly accepted by patients. Therefore, we aimed to identify a diagnostic serum protein signature and validate its performance and utility. Methods Proximity extension immunoassay (PEA) methodology (Olink Proteomics, Uppsala, Sweden) was used to measure 184 immune and inflammatory markers in serum samples from adult patients with suspected IBD in the Swedish inception cohort SIC IBD (discovery cohort, n=451) and the Norwegian population-based inception cohort IBSEN III (validation cohort, n=554). Samples were obtained at presentation, i.e., almost all patients were treatment naïve. Diagnostic assessment was performed following the ECCO guidelines. Supervised machine learning with smoothly clipped absolute deviation (SCAD) regularised logistic regression and random forest (RF) models were employed in nested cross-validation to identify a diagnostic signature of IBD. Results The discovery cohort included 310 IBD patients and 141 symptomatic controls without any discernible evidence of IBD, and the validation cohort included 354 IBD patients and 200 symptomatic controls (Table 1). The regularised regression identified a signature of 26 proteins that distinguished IBD from symptomatic controls with an area under the curve (AUC) of 0.78 in the discovery cohort. Contributions of individual proteins for the diagnostic signature are shown in Figure 1. Next, we validated the diagnostic capacity of the protein signature in the validation cohort (AUC=0.82) and compared it to high-sensitivity C-reactive protein (hsCRP) (Figure 2, AUC=0.69, p=1.1×10-7). The RF model yielded similar results. Only 422/554 patients in the validation cohort provided a stool sample. Among these patients, the diagnostic accuracy of the protein signature (AUC=0.82) and faecal Calprotectin (AUC=0.86) did not differ (p=0.07). A complex protein signature may preclude its introduction into clinical practice. Simplified models were therefore constructed using discovery cohort data and stepwise forward logistic regression with hsCRP as the null model. When applied to the validation cohort, the diagnostic accuracy of the shortest signature, comprising hsCRP and interleukin (IL)-17A (AUC=0.80), was superior to hsCRP (Figure 3, AUC=0.69, p=1.7×10-8). Conclusion A serum protein signature of hsCRP and IL-17A was superior to hsCRP in differentiating treatment-naïve IBD from symptomatic controls. Taking into account that many patients do not accept to provide faecal samples, we believe this signature has the potential to become an accessible and scalable test that can shorten the diagnostic delay in IBD.

DOP06 Deep characterization of IL-23 pathway in different gut segments and associated plasma biomarkers in inflammatory bowel disease

Abstract Background The role of Interleukin 23 (IL-23) in the pathogenesis of both Crohn’s disease (CD) and ulcerative colitis (UC) is well documented. However, more than half of patients do not respond or lose response to current anti-IL-23 treatments. Thus, we aimed to identify patients with IL-23-driven disease using gut segment-specific transcriptome analysis and quantification of IL-23 pathway cytokines in plasma to enable patient stratification in inflammatory bowel disease (IBD). Methods Analyses of real-world data from the Study of a Prospective Adult Research Cohort with IBD (SPARC IBD) obtained from the IBD Plexus program of the Crohn’s & Colitis Foundation including clinical, plasma biomarker (IL-22, IL-23, INF-γ, and IL-17A), and mucosal ileum and colon transcriptome data. Results To differentiate IL-23 from TNF-driven disease, we performed gene set variation analysis (GSVA) using IL-23 and TNF gene sets and ileal and colonic transcriptome data from 1230 CD and 664 UC patients. An IL-23, but not TNF, transcriptional module was enriched in ileal compared to colonic biopsies in CD (p < 0.001​). IL-23 pathway activity was significantly higher in uninflamed Ileal compared to colonic biopsies from CD patients (p < 0.001)​). Importantly, IL-23 pathway activity was increased in intestinal biopsies from macroscopically inflamed compared to uninflamed regions, from all gut segments in both CD and UC and correlated with the endoscopic score for both diseases (Fig 1). We also observed higher plasma IL-22 levels in both CD and UC patients with moderate to severely active disease compared with patients in remission (Fig 2). We found that tissue IL-23 pathway activity was linked to plasma biomarker levels in general. The subgroup of CD patients with elevated plasma IL-22 levels showed higher IL-23 pathway activity in the ileum (p=0.003) and colon (p=0.013). In UC, patients with elevated plasma IL-22 levels showed higher IL-23 pathway activity in the sigmoid colon (p=0.001), but not the cecum (p=0.141) (Fig 3). Conclusion IL-23 pathway activity in different segments of the gut may contribute differently to pathogenesis in CD, while IL-23 pathway activity is similar across colonic segments in UC. The association between plasma biomarker levels and gut tissue IL-23 pathway activity suggests that quantifying plasma IL-22 levels could be a valuable tool to assess the efficacy of anti-IL-23 therapy in IBD.

P657 Current landscape of the real-world utilization of Interleukins 22, 23 and Interleukin 22 binding protein as biomarkers for Inflammatory Bowel Disease (IBD): A targeted literature review

Abstract Background Precision medicine is an active area of IBD research. Evidence underpinning the role of IL-22, IL-23, and IL-22 binding protein (BP) as biomarkers of mechanistic pathways, diagnosis, disease severity, and treatment response has been accumulating. Little is known about the applications of these ILs as biomarkers in real-world studies. The aim of this literature review was to describe the current landscape of assessing IL-22, IL-23 and IL-22BP in real-world studies. Methods A search was undertaken in MEDLINE and Embase to identify English-language manuscripts (2018-2021) and conference abstracts (2019-2021) of real-world studies in adult IBD, measuring IL-22, IL-23, or IL-22BP. One reviewer screened titles/abstracts for eligibility using a standardized form. A second reviewer independently screened a random sample of publications and disagreements were resolved by a third reviewer. Results Titles and abstracts of 369 studies were screened. Forty-two studies met the eligibility criteria and were included for full-text screening. Seventeen studies were then excluded because they lacked key information such as the study design or the clinical application. A total of 25 studies were included. Of those, three were conference abstracts. Nine (36%), eight (32%), and eight (32%) studies included patients with CD only, UC only, and both CD and UC with/without their comparison groups, respectively. Eleven studies (44%) were conducted in Europe, 10 (40%) in Asia, two (8%) in North America, and one (4%) each in Africa and the Middle East. Twelve (48.0%) studies reported on IL-23, 11 (44.0%) on IL-22 and one (4.0%) on IL-22BP. Most publications reported on more than one IL with multiple applications. Eight (28%) studies examined diagnostic applications, 11 (38%) prediction of severity, and 10 (34%) prediction of treatment response. Multiple sampling sources were used, including tissue (38%), serum (34%), cell (16%), blood(9%), and plasma (3%). IL-23 levels were consistently correlated with IBD severity when comparing IBD with healthy controls, but the data was less consistent for IL-23 as a diagnostic test or predictor of treatment response. The reported correlations for IL-22 and IL-22BP varied across studies. This was potentially due to heterogeneous study methodologies. Conclusion This literature review shows that IL-22, IL-22BP and IL-23 have been studied in the real world for diagnosis, prediction of disease severity, and treatment response in IBD; however, there was heterogeneity in methodologies, ethnic composition, and sample types across studies. The correlation of IL-22 level with the studied outcomes was qualitatively inconsistent across studies and applications, whereas IL-23 was found to be consistently associated with IBD severity.

P106 Identification of urine and serum diagnostic biomarkers of inflammatory bowel disease using a proteomic approach

Abstract Background Inflammatory bowel diseases (IBD) are chronic, heterogeneous, and inflammatory conditions mainly affecting the gastrointestinal tract. Currently, endoscopy is the gold standard test for assessing mucosal activity and healing in clinical practice; however, it is a costly, time-consuming, invasive, and uncomfortable procedure for patients. There is, therefore, a need for sensitive, specific, fast and non-invasive biomarkers for the diagnosis of IBD. Methods Label-free quantification by nanoscale liquid chromatography coupled to tandem mass spectrometry (nLC MS/MS) was performed to profile the urinary and serum proteomes of 100 patients with newly diagnosed IBD, before starting any treatment [50 patients with Crohn′s disease (CD) and 50 patients with ulcerative colitis (UC)] and 50 healthy controls (HC). Data Mining and Pattern Recognition techniques were used to identify hidden relationships that are not detectable by using the classical and most commonly used lineal classifiers; and thus, identifying potential markers able to discriminate the studied cohorts. Finally, we applied Ingenuity Pathway Analysis (IPA) to analyze the pathways and functions of differentially expressed proteins. Results Serum proteomics results revealed 45 differentially expressed proteins in the comparison between UC and HC groups, 32 proteins significantly expressed in CD versus HC, and 12 proteins in CD compared with UC. In urine samples, 110 proteins were significantly changed in UC versus HC, 50 proteins were differentially expressed between CD and HC, and a total of 31 proteins were significantly changed in CD compared with UC patients. Receiver operating characteristic curve (ROC) analysis found multiple proteins with high area under the curve values, up to 0.94, indicating that these serum and urine proteins are of value as new non-invasive diagnostic classifiers of IBD patients. For each study comparative, the 5 most significant classifiers were selected (Figures 1 and 2). IPA revealed multiple signaling pathways, including prothrombin activation, acute phase response signaling, complement and coagulation system and liver X receptor/retinoid X receptor (LXR/RXR) activation, altered in IBD patients compared to HC (p-value < 0.05) (Figures 3 and 4). Conclusion Our findings indicate that analysis of the urine and serum proteome using nLC MS/MS is a feasible approach for biomarker discovery. We identified several serum and urine proteins that could serve as new non-invasive markers for the diagnosis of IBD patients after further validation. After bioinformatic analyses, we found multiple proteins that may play important roles in the pathogenesis of IBD.

Characterization of the Fecal and Mucosa-Associated Microbiota in Dogs with Chronic Inflammatory Enteropathy.

Canine chronic inflammatory enteropathy implicates multifactorial pathogenesis where immunological dysregulation and gut microbiota changes have a central role. Most sequencing-based taxonomic studies have been focused on the fecal microbiota. However, the analysis of these samples does not provide complete information regarding the composition of the small intestine affected by this canine disease. Therefore, in this study, we aimed to characterize the intestinal bacterial microbiota in dogs with inflammatory bowel disease (IBD) (n = 34) by means of duodenal biopsies and fecal samples collected at the time of the diagnosis and to compare those to a group of healthy dogs (n = 12) using the 16S ribosomal RNA (16S rRNA) gene-targeted sequencing (Illumina MiSeq platform). Our study showed that IBD dogs presented differences in the fecal bacterial communities when compared with healthy dogs, with a lower relative abundance of Prevotellaceae (p = 0.005), Prevotella (p = 0.002), and Prevotellaceae Ga6A1 group (0.006); Erysipelotrichales (p = 0.019), Candidatus Stoquefichus (p < 0.001), Erysipelotrichaceae (p = 0.011), and Allobaculum (p = 0.003); Lachnospiraceae NK4A136 group (p = 0.015), Sellimonas (p = 0.042), Oscillospirales (p = 0.037), Oscillospiraceae UCG-005 (p < 0.001), Faecalibacterium (p = 0.028), and Fournierella (p = 0.034); Acidaminococcales, Acidaminococcaceae, and Phascolarctobacterium (p = 0.001); Aeromonadales (p = 0.026), Succinivibrionaceae (p = 0.037), and Succinivibrio (p = 0.031). On the other hand, a higher relative abundance of Enterococcaceae (Enterococcus; p = 0.003), Streptococcaceae (Streptococcus, p = 0.021), Enterobacterales (p = 0.027), Enterobacteriaceae (p = 0.008), and Escherichia-Shigella (p = 0.011) was detected. Moreover, when evaluating α-diversity, the dogs with IBD showed lower diversity in terms of richness and abundance of species (observed species [p = 0.031] and Shannon index [p = 0.039]). Furthermore, fecal microbiota in dogs with IBD was significantly different from healthy dogs (p = 0.006). However, only a few taxa relative abundance shifts (lower Rubrobacteria, Rubrobacterales, Rubrobacteriaceae, and Rubrobacter [p = 0.002]; Cyanobacteria [p = 0.010], Vampirivibrionia, Obscuribacterales, and Obscuribacteraceae [p = 0.005]; Neisseriaceae [p = 0.004] and Conchiformibius [p = 0.003]) were observed when assessing duodenal-associated microbiota of dogs with IBD. Thus, even if the bowel inflammation mainly affects the small intestine in the IBD-affected dogs of the study, fecal specimens may constitute a better sample due not only to their easy availability but also in terms of searching for bacterial taxa as biomarkers for canine IBD. The use of different diets in the study can also have a partial influence on the microbiota composition. Future studies encompassing multi-omics approaches should evaluate the functionality in both levels to unravel the pathophysiology of canine IBD.

Machine learning-based feature selection to search stable microbial biomarkers: application to inflammatory bowel disease.

Biomarker discovery exploiting feature importance of machine learning has risen recently in the microbiome landscape with its high predictive performance in several disease states. To have a concrete selection among a high number of features, recursive feature elimination (RFE) has been widely used in the bioinformatics field. However, machine learning-based RFE has factors that decrease the stability of feature selection. In this article, we suggested methods to improve stability while sustaining performance. We exploited the abundance matrices of the gut microbiome (283 taxa at species level and 220 at genus level) to classify between patients with inflammatory bowel disease (IBD) and healthy control (1,569 samples). We found that applying an already published data transformation before RFE improves feature stability significantly. Moreover, we performed an in-depth evaluation of different variants of the data transformation and identify those that demonstrate better improvement in stability while not sacrificing classification performance. To ensure a robust comparison, we evaluated stability using various similarity metrics, distances, the common number of features, and the ability to filter out noise features. We were able to confirm that the mapping by the Bray-Curtis similarity matrix before RFE consistently improves the stability while maintaining good performance. Multilayer perceptron algorithm exhibited the highest performance among 8 different machine learning algorithms when a large number of features (a few hundred) were considered based on the best performance across 100 bootstrapped internal test sets. Conversely, when utilizing only a limited number of biomarkers as a trade-off between optimal performance and method generalizability, the random forest algorithm demonstrated the best performance. Using the optimal pipeline we developed, we identified 14 biomarkers for IBD at the species level and analyzed their roles using Shapley additive explanations. Taken together, our work not only showed how to improve biomarker discovery in the metataxonomic field without sacrificing classification performance but also provided useful insights for future comparative studies.

Resistin, Elastase, and Lactoferrin as Potential Plasma Biomarkers of Pediatric Inflammatory Bowel Disease Based on Comprehensive Proteomic Screens

Inflammatory bowel disease (IBD) is an immune-mediated chronic inflammation of the intestine, which can present in the form of ulcerative colitis (UC) or as Crohn’s disease (CD). Biomarkers are needed for reliable diagnosis and disease monitoring in IBD, especially in pediatric patients. Plasma samples from a pediatric IBD cohort were interrogated using an aptamer-based screen of 1322 proteins. The elevated biomarkers identified using the aptamer screen were further validated by ELISA using an independent cohort of 76 pediatric plasma samples, drawn from 30 CD, 30 UC, and 16 healthy controls. Of the 1322 proteins screened in plasma from IBD patients, 129 proteins were significantly elevated when compared with healthy controls. Of these 15 proteins had a fold change greater than 2 and 28 proteins had a fold change >1.5. Neutrophil and extracellular vesicle signatures were detected among the elevated plasma biomarkers. When seven of these proteins were validated by ELISA, resistin was the only protein that was significantly higher in both UC and CD (p < 0.01), with receiver operating characteristic area under the curve value of 0.82 and 0.77, respectively, and the only protein that exhibited high sensitivity and specificity for both CD and UC. The next most discriminatory plasma proteins were elastase and lactoferrin, particularly for UC, with receiver operating characteristic area under the curve values of 0.74 and 0.69, respectively. We have identified circulating resistin, elastase, and lactoferrin as potential plasma biomarkers of IBD in pediatric patients using two independent diagnostic platforms and two independent patient cohorts.

Clinical and inflammatory biomarkers of inflammatory bowel diseases are linked to plasma trace elements and toxic metals; new insights into an old concept.

Inflammatory bowel diseases (IBD) are chronic immune-mediated diseases, mainly represented by Crohn's disease (CD) and ulcerative colitis (UC). Several environmental factors have been proposed to contribute to disease pathogenesis, amongst which are metals. These can affect the immune system and may be associated with IBD. The aim of the present cross-sectional study was to investigate blood levels of metals in IBD patients and to examine possible associations with clinical and inflammatory disease markers. In total, 76 CD patients, 39 UC patients and 38 healthy controls were included. Blood and stool samples were collected. Metals were quantified in plasma samples using inductively coupled plasma mass spectrometry. There were more abnormalities of circulating metals in CD than in UC when compared to healthy controls. CD: Concentrations of the essential trace elements zinc and selenium were lower in CD patients than the controls. Chromium was negatively associated with serum IL-6 (Beta: -3.558, p = 0.011), and caesium with fecal calprotectin (Beta: -0.481, p = 0.038) and serum IL-10 (Beta: -1.912, p = 0.050). In contrast, copper was positively associated with C-reactive protein (Beta: 2.548 × 102, p = 0.033). UC: In UC, a negative association of iron with serum myeloperoxidase levels (Beta: -1.270 × 103, p = 0.044) was detected. Thallium, a hazardous metal, however, was positively associated with disease activity (Beta: 3.899, p = < 0.01). In conclusion, our study offers new insights into the relations of metals with IBD. Further research should focus on the evaluation of the above associations and potential underlying mechanisms.

Serum calprotectin is useful to confirm inflammatory bowel disease activity but not to predict relapse

Serum calprotectin (SC), a novel biomarker of inflammatory bowel diseases (IBD), has been recently investigated with conflicting results. The purpose of this study was to assess the ability of SC to predict relapse in IBD patients treated by biologic therapies, and to evaluate the correlation between SC, clinical and endoscopic relapse and other biomarkers as fecal calprotectin (FC) and C-reactive protein (CRP).

Human Fecal Mucin Glycosylation as a New Biomarker in Inflammatory Bowel Diseases.

Lay Summary For the first time, fecal mucins of Crohn’s disease patients were analyzed by mass spectrometry. Compared with control subjects, Crohn’s disease patients showed a significant decrease in sialylated glycans that we propose as new noninvasive tool for screening of intestinal diseases.

Urinary chemerin as a potential biomarker for inflammatory bowel disease.

Systemic levels of the adipokine chemerin are elevated in different inflammatory conditions such as inflammatory bowel disease (IBD). In IBD, chemerin protein expression in colon mucosa is induced and serum chemerin levels are increased. Aim of this study was to identify chemerin protein in human feces and/or urine and to evaluate a possible association with IBD activity. Feces and urine of 40 patients with IBD and the respective sera of 34 patients were collected. Chemerin levels were analyzed by immunoblot in feces and urine samples. In addition, enzyme-linked immunosorbent assay (ELISA) was used to measure chemerin in all urine, feces and serum samples of the patients and in urine of 17 healthy controls. Chemerin was not detectable in 80% of the human feces samples by ELISA. Chemerin in human urine was detected by immunoblot and ELISA. Compared to serum levels, urinary concentration was about 6,000-fold lower. Urinary chemerin did not differ between patients with ulcerative colitis (n = 15) and Crohn's disease (n = 25). Urinary chemerin was not related to its serum levels, did not correlate with serum C-reactive protein level and negatively correlated with serum creatinine. Of note, urinary chemerin of patients with a fecal calprotectin > 500 μg/g was significantly higher compared to patients with lower calprotectin levels and compared to healthy controls. Serum creatinine did not differ between the patient groups. Urinary chemerin might present a novel non-invasive biomarker for monitoring IBD severity and clinical course.

Electrolyzed Hydrogen Water Alleviates Abdominal Pain through Suppression of Colonic Tissue Inflammation in a Rat Model of Inflammatory Bowel Disease.

Inflammatory bowel disease (IBD) is characterized by chronic inflammation of the digestive tract and is typically accompanied by characteristic symptoms, such as abdominal pain, diarrhea, and bloody stool, severely deteriorating the quality of the patient's life. Electrolyzed hydrogen water (EHW) has been shown to alleviate inflammation in several diseases, such as renal disease and polymyositis/dermatomyositis. To investigate whether and how daily EHW consumption alleviates abdominal pain, the most common symptom of IBD, we examined the antioxidative and anti-inflammatory effects of EHW in an IBD rat model, wherein colonic inflammation was induced by colorectal administration of 2,4,6-trinitrobenzene sulfonic acid (TNBS). We found that EHW significantly alleviated TNBS-induced abdominal pain and tissue inflammation. Moreover, the production of proinflammatory cytokines in inflamed colon tissue was also decreased significantly. Meanwhile, the overproduction of reactive oxygen species (ROS), which is intricately involved in intestinal inflammation, was significantly suppressed by EHW. Additionally, expression of S100A9, an inflammatory biomarker of IBD, was significantly suppressed by EHW. These results suggest that the EHW prevented the overproduction of ROS due to its powerful free-radical scavenging ability and blocked the crosstalk between oxidative stress and inflammation, thereby suppressing colonic inflammation and alleviating abdominal pain.

Intercontinental Gut Microbiome Variances in IBD.

The development of biomarkers for inflammatory bowel disease (IBD) diagnosis would be relevant in a generalized context. However, intercontinental investigation on these microbial biomarkers remains scarce. We examined taxonomic microbiome variations in IBD using published DNA shotgun metagenomic data. For this purpose, we used sequenced data from our previous Spanish Crohn’s disease (CD) and ulcerative colitis (UC) cohort, downloaded sequence data from a Chinese CD cohort, and downloaded taxonomic and functional profiling tables from a USA CD and UC cohort. At the global level, geographical location and disease phenotype were the main explanatory covariates of microbiome variations. In healthy controls (HC) and UC, geography turned out to be the most important factor, while disease intestinal location was the most important one in CD. Disease severity correlated with lower alpha-diversity in UC but not in CD. Across geography, alpha-diversity was significantly different independently of health status, except for CD. Despite recruitment from different countries and with different disease severity scores, CD patients may harbor a very similar microbial taxonomic profile. Our study pointed out that geographic location, disease activity status, and other environmental factors are important contributing factors in microbiota changes in IBD. We therefore strongly recommend taking these factors into consideration for future IBD studies to obtain globally valid and reproducible biomarkers.

Prebiotics-Controlled Disposable Engineered Bacteria for Intestinal Diseases.

As a new method of diagnosis and treatment for intestinal diseases, intelligent engineered bacteria based on synthetic biology have been developed vigorously in recent years. However, how to deal with the engineered bacteria in vivo after completing the tasks is an urgent problem to be resolved. In this study, we constructed a thiosulfate (a biomarker of inflammatory bowel disease)-responsive engineered bacteria to generate two signals, sfGFP (monitoring) and gain-of-function (translation activation) mutation (ACG to ATG), in the initiation codon of lysisE (recording) via the CRISPR/Cas9-mediated base editing system. Once these two signals were detected, xylose could be added to induce lysis E expression, resulting in the destruction of the edited bacteria and the release of AvCystain simultaneously. Overall, our innovative engineered bacteria can record instant and historical information of the disease, and especially, the edited bacteria can be artificially attenuated and release drug in situ when needed, ultimately serving as a disposable and recyclable candidate for more types of diseases.

The Nocebo Effect in a Non-Medical Switching Program from Originator to Biosimilar Infliximab in Inflammatory Bowel Disease.

Despite growing awareness of the nocebo effect, few studies have evaluated the nocebo effect using combined assessment of patient-reported outcome measures (PROMs), clinical indices, and objective biomarkers in inflammatory bowel disease (IBD) patients switching from originator to biosimilar medicines. This study aimed to compare these outcomes across switch and non-switch cohorts to evaluate the nocebo effect in patients with IBD. Parallel cohorts of IBD patients who (1) switched from originator to biosimilar (CT-P13) infliximab and (2) continued biosimilar (CT-P13) infliximab were evaluated over 32 weeks. Clinical disease activity, objective biomarkers and PROMs were assessed at baseline, and weeks 16 and 32 across both cohorts. The PROM of interest was patient-perceived disease activity evaluated using a 0-100 visual analogue scale (VAS) per the IBD-Control Questionnaire. Of 81 patients, 47 switched from originator to biosimilar (CT-P13) infliximab. A negative change from baseline patient-reported disease control was observed across the switch cohort compared with the non-switch cohort at week 16 (mean VAS - 8.21 vs. 1.26; p=0.03), but not at week 32 (mean VAS - 1.21 vs. 1.38; p=0.58). Corresponding clinical and objective biomarker assessments over these timepoints were comparable across both cohorts. This study demonstrated a temporary yet discernible nocebo effect in the first 16 weeks following non-medical switching that was not sustained at week 32. Negative patient perceptions may be overcome by a patient-inclusive approach to non-medical switching in conjunction with close clinical follow-up and disease monitoring.

Fecal calprotectin as a biomarker of intestinal inflammation in ICU patients with diarrhea – testing the pipette method against the collection pin and weighing methods

Fecal calprotectin is an established biomarker in inflammatory bowel disease, but its role in assessment of intestinal inflammation in ICU patients is yet to be explored. ICU patients tend to acquire diarrhea, which complicates the extraction of fecal calprotectin using a collection pin for stool sampling. Pipetting is an alternative sampling method. The aim of the study was to compare the collection pin method with the pipette method for measurement of fecal calprotectin in ICU patients with diarrhea. Stool samples were collected from fecal bags used in the patients and then analyzed for calprotectin using an extraction device and a piston pipette, respectively. In addition, a validation test for the pipette method of extraction was conducted on liquid stool samples. Eleven stool samples were collected from five randomly selected ICU patients. Calprotectin was detectable in all fecal samples. On average the collection pin measured 45% lower than the pipette method with a 95% confidence interval (30 − 59%). The coefficient of variation when using the pipette method was 13% in low calprotectin concentrations and 39% in high concentrations. In conclusion, the pipette method seems to be appropriate for measuring calprotectin in liquid feces, due to practicalities and a greater precision.

MiR‑146a‑5p negatively regulates the IL‑1β‑stimulated inflammatory response via downregulation of the IRAK1/TRAF6 signaling pathway in human intestinal epithelial cells.

The primary pathophysiological alteration caused by inflammatory bowel disease (IBD) is prolonged, excessive inflammatory response to stimulation factors, which leads to intestinal mucosal lesions. microRNA (miR)-146a-5p is broadly activated in the mucosal immune response. At present, the biogenesis, function and role of miR-146a-5p in intestinal epithelial cells (IECs) during the pathogenesis of IBD remain elusive. The human colon cancer epithelial Caco-2 cell line was cultured with 10 ng/ml recombinant human IL-1β for 3 h to establish an in vitro IECs inflammatory model. Relative levels of miR-146a-5p and inflammatory factors (IL-6, IL-1β, TNF-α and IP-10) were measured by reverse transcription-quantitative PCR (RT-qPCR) and western blotting. Transfection of miR-146a-5p mimic or inhibitor into Caco-2 cells was performed to identify the influence of miR-146a-5p on Caco-2 cell inflammatory factors expression. The targeting relationship between miR-146a-5p and interleukin 1 receptor associated kinase 1 (IRAK1)/tumor necrosis factor receptor-associated factor 6 (TRAF6) was predicted by TargetScan 8.0. The present study demonstrated that miR-146a-5p and inflammatory factors (IL-6, IL-1β, TNF-α and IP-10) were upregulated in a dose- and time-dependent manner in IL-1β-stimulated Caco-2 cells. Moreover, upregulation of miR-146a-5p negatively regulated the expression of inflammatory factors, but the downregulation of miR-146a-5p increased their expression. The results of the present study demonstrated that miR-146a-5p decreased the expression of the inflammatory factors through targeted downregulation of IRAK1/TRAF6. These results suggest that miR-146a-5p negatively regulates the IL-1β-stimulated inflammatory response via downregulation of the IRAK1/TRAF6 signaling pathway in human IECs. Therefore, miR-146a-5p may act as an important diagnostic biomarker and treatment target of IBD.