Biomarkers in inflammatory bowel disease: current practices and recent advances

Causal association of blood cell traits with inflammatory bowel diseases: a Mendelian randomization study

Background

Observational studies have found associations between blood cell traits and inflammatory bowel diseases (IBDs), whereas the causality and dose-effect relationships are still undetermined.

Methods

Two-sample Mendelian randomization (MR) analyses using linear regression approaches, as well as Bayesian model averaging (MR-BMA), were conducted to identify and prioritize the causal blood cell traits for Crohn's disease (CD) and ulcerative colitis (UC). An observational study was also performed using restricted cubic spline (RCS) to explore the relationship between important blood cell traits and IBDs.

Results

Our uvMR analysis using the random effects inverse variance weighted (IVW) method identified eosinophil (EOS) as a causal factor for UC (OR = 1.36; 95% CI: 1.13, 1.63). Our MR-BMA analysis further prioritized that high level of lymphocyte (LYM) decreased CD risk (MIP = 0.307; θ ^ MACE = -0.059; PP = 0.189; θ ^ λ = -0.173), whereas high level of EOS increased UC risk (MIP = 0.824; θ ^ MACE = 0.198; PP = 0.627; θ ^ λ = 0.239). Furthermore, the observational study clearly depicts the nonlinear relationship between important blood cell traits and the risk of IBDs.

Conclusion

Using MR approaches, several blood cell traits were identified as risk factors of CD and UC, which could be used as potential targets for the management of IBDs. Stratified genome-wide association studies (GWASs) based on the concentration of traits would be helpful owing to the nonlinear relationships between blood cell traits and IBDs, as demonstrated in our clinical observational study. Together, these findings could shed light on the clinical strategies applied to the management of CD and UC.

Plasma Extracellular Vesicle LncRNA H19 as a Potential Diagnostic Biomarker for Inflammatory Bowel Diseases

BACKGROUND

Inflammatory bowel disease (IBD) is a complex gastrointestinal disease with 2 main subtypes of Crohn's disease (CD) and ulcerative colitis (UC), whose diagnosis mainly depends on the medical history, clinical symptoms, endoscopic, histologic, radiological, and serological findings. Extracellular vesicles (EVs) are now considered an additional mechanism for intercellular communication, allowing cells to exchange biomolecules. Long noncoding RNAs (lncRNAs) that are enriched in EVs have been defined as an ideal diagnostic biomarker for diseases. In this study, we investigated the expression differences of 5 lncRNAs in tissue and plasma EVs of active IBD patients compared with patients in the remission phase and healthy controls to introduce an EV-lncRNA as a noninvasive IBD diagnostic biomarker.

METHODS

Twenty-two active IBD patients, 14 patients in the remission phase, 10 active rheumatoid arthritis (RA) patients, 14 irritable bowel syndrome (IBS) patients, and 22 healthy individuals were recruited in the discovery cohort. In addition, 16 patients with active IBD, 16 healthy controls, 10 inactive IBD patients, 12 active RA patients, and 14 IBS patients were also included in the validation cohort. The expression levels of 5 lncRNAs in tissue and EV-plasma were evaluated by quantitative real-time polymerase chain reaction (qRT-PCR) . Machine learning and receiver operating characteristic (ROC) curve analysis were performed to investigate the distinguishing ability of the candidate biomarkers.

RESULTS

While the expression levels of lncRNAs CDKN2B-AS1, GAS5, and TUG1 were significantly downregulated, lncRNAs H19 and CRNDE were overexpressed in active IBD lesions. Expression of H19 was detected in plasma EVs whose isolation had been confirmed via dynamic light scattering, microscopy images, and western blotting. The classification results demonstrated the excellent ability of H19 in distinguishing IBD/active from IBD/remission, healthy control, RA, and IBS (area under the ROC curve = 0.95, 0.97,1, and 0.97 respectively).

CONCLUSIONS

Our study suggests that circulating EV-lncRNA H19 exhibited promising potential for the diagnosis of active IBD.

Prevalence of spondyloarthritis in inflammatory bowel disease according ASAS and ultrassonography and its correlation with plasma calprotectin

BACKGROUND

Enteropathic spondyloarthritis is underdiagnosed and inflammatory biomarkers and ultrasonography (US) could be useful for screening inflammatory bowel disease (IBD) patients. The objective of this study was to evaluate the prevalence of spondyloarthritis (SpA) in IBD patients, according to the Assessment of SpondyloArthritis International Society (ASAS) criteria and the correlation of results of US of entheses and joints with plasma calprotectin levels.

METHODS

This was an observational cross-sectional study. Patients from the IBD outpatient clinic of a reference center were evaluated according to ASAS criteria classification, results of US of entheses and joints, and inflammatory biomarker measurements (erythrocyte sedimentation rates, C-reactive protein levels, fecal and plasma calprotectin levels). A p value lower than 0.05 was considered significant.

RESULTS

A total of 30.5% of the studied sample (n = 118) of patients with IBD presented at least one inflammatory musculoskeletal manifestation. The overall prevalence of enteropathic SpA was 13.55%, with 10.16% axial SpA and 4.23% peripheral SpA according to the ASAS criteria. A total of 42.1% of patients had an MASEI score greater than 18, 35.2% had synovitis, and 14.7% had tenosynovitis on US, increasing the frequency of diagnosis of enteropathic SpA to 22.8%. Plasma calprotectin levels were similar to those in healthy controls, and correlated only with the fecal calprotectin level (p 0.041).

CONCLUSIONS

A total of 13.5% of patients met the criteria in accordance with the ASAS criteria for enteropathic SpA, which increased to 22.8% with the addition of US. The prevalence of enthesitis, synovitis and tenosynovitis by US of symptomatic joints and entheses were 42%, 35% and 14.7% respectively. Plasma calprotectin was correlated with fecal calprotectin but not with inflammatory biomarkers or US or ASAS criteria.

Paradigm shift in biomarker translation: a pipeline to generate clinical grade biomarker candidates from DIA-MS discovery

Clinical biomarker development has been stymied by inaccurate protein quantification from mass spectrometry (MS) discovery data and a prolonged validation process. To mitigate these issues, we created the Targeted Extraction Assessment of Quantification (TEAQ) software package. This innovative tool uses the discovery cohort analysis to select precursors, peptides, and proteins that adhere to established targeted assay criteria. TEAQ was applied to Data-Independent Acquisition MS data from plasma samples acquired on an Orbitrap™ Astral™ MS. Identified precursors were evaluated for linearity, specificity, repeatability, reproducibility, and intra-protein correlation from 11-point loading curves under three throughputs, to develop a resource for clinical-grade targeted assays. From a clinical cohort of individuals with inflammatory bowel disease (n=492), TEAQ successfully identified 1116 signature peptides for 327 quantifiable proteins from 1180 identified proteins. Embedding stringent selection criteria adaptable to targeted assay development into the analysis of discovery data will streamline the transition to validation and clinical studies.

Predictive Model for Prognosis of Sudden Sensorineural Hearing Loss by Nomogram

Objective: To explore the prognostic factors of patients with sudden sensorineural hearing loss (SSNHL), analyze the possible influencing factors, and construct a nomogram for personalized evaluation of their prognosis. Methods: A retrospective study was conducted on 269 patients with SSNHL. The prognostic factors were analyzed by univariate analysis and multivariate logistic regression analysis. The nomogram was constructed based on the results of multivariate logistic regression analysis, and the model was verified by receiver operating characteristic (ROC) curve, calibration curve, and decision curve analysis (DCA). Results: Among the 269 patients hospitalized, 136 cases were improved (44 cases were cured, 28 cases were markedly effective, 64 cases were effective) and 133 cases were ineffective. After univariate analysis, it was found that age, duration from onset to treatment, audiometric configuration, serum albumin (ALB), and neutrophil-to-lymphocyte ratio (NLR) were associated with hearing outcomes. Duration from onset to treatment and audiometric configuration were independent risk factors when the treatment outcome was divided into ineffective, effective, significant improvement, and complete recovery groups or divided into improvement and ineffective groups after multivariate logistic regression analysis. The factors according to univariate analysis and multivariate logistic regression analysis results were included in the nomogram to construct the prediction models. The area under the ROC curve of model discrimination was 0.752 [95% confidence interval (CI): 0.695-0.808] when the treatment outcome was divided into 2 groups. The calibration curve showed the consistency of the results, and the DCA prediction curve showed good clinical efficacy. The C-index was 0.756 (95% CI: 0.710-0.802) when the treatment outcome was divided into 4 groups. Conclusion: Age, duration from onset to treatment, audiometric configuration, ALB, and NLR are influencing factors for SSNHL. Duration from onset to treatment and audiometric configuration are independent risk factors for SSNHL. The nomogram presents the prognosis of patients with SSNHL in an intuitive, visual, and readable graph, providing clinicians with a personalized assessment.

The pan-microbiome profiling system Taxa4Meta identifies clinical dysbiotic features and classifies diarrheal disease

Targeted metagenomic sequencing is an emerging strategy to survey disease-specific microbiome biomarkers for clinical diagnosis and prognosis. However, this approach often yields inconsistent or conflicting results owing to inadequate study power and sequencing bias. We introduce Taxa4Meta, a bioinformatics pipeline explicitly designed to compensate for technical and demographic bias. We designed and validated Taxa4Meta for accurate taxonomic profiling of 16S rRNA amplicon data acquired from different sequencing strategies. Taxa4Meta offers significant potential in identifying clinical dysbiotic features that can reliably predict human disease, validated comprehensively via reanalysis of individual patient 16S data sets. We leveraged the power of Taxa4Meta's pan-microbiome profiling to generate 16S-based classifiers that exhibited excellent utility for stratification of diarrheal patients with Clostridioides difficile infection, irritable bowel syndrome, or inflammatory bowel diseases, which represent common misdiagnoses and pose significant challenges for clinical management. We believe that Taxa4Meta represents a new "best practices" approach to individual microbiome surveys that can be used to define gut dysbiosis at a population-scale level.

Personalized Treatment for Crohn's Disease: Current Approaches and Future Directions

Crohn's disease is a complex, relapsing and remitting inflammatory disorder of the gastrointestinal tract with a variable disease course. While the treatment options for Crohn's disease have dramatically increased over the past two decades, predicting individual patient response to treatment remains a challenge. As a result, patients often cycle through multiple different therapies before finding an effective treatment which can lead to disease complications, increased costs, and decreased quality of life. Recently, there has been increased emphasis on personalized medicine in Crohn's disease to identify individual patients who require early advanced therapy to prevent complications of their disease. In this review, we summarize our current approach to management of Crohn's disease by identifying risk factors for severe or disabling disease and tailoring individual treatments to patient-specific goals. Lastly, we outline our knowledge gaps in implementing personalized Crohn's disease treatment and describe the future directions in precision medicine.

Alteration of stool pH and its association with biomarkers of gut enteropathy among slum-dwelling women of reproductive age in Bangladesh

BACKGROUND

Recent evidence suggests that measures of maternal gut enteropathy are associated with unfavorable fetal outcomes. It is, therefore, crucial to identify and treat the features of intestinal enteropathy among reproductive-age women living in areas where enteropathy is highly prevalent. However, there is a lack of non-invasive diagnostic tests to determine EED, making it difficult to identify the disease in field settings. In this study, we tested the potential of fecal pH as a biomarker of gut enteropathy and investigated its relationship with fecal biomarkers of intestinal enteropathy in reproductive-age women living in resource-limited environments.

METHODS

Data on socio-demographic information, anthropometry, and biological samples were collected from 78 apparently healthy women aged between 20 and 27 years from November 2018 to December 2019. The association of stool pH with two fecal biomarkers of gut enteropathy (i.e., intestinal alkaline phosphatase [IAP] and fecal lipocalin-2 [LCN-2] was investigated using multiple linear regression models after adjusting for relevant covariates.

RESULTS

In the adjusted models, alkaline stool pH (pH > 7.2) was found to be significantly associated with a decrease in the fecal IAP level by 1.05 unit (95% CI: -1.68, -0.42; p < 0.001) in the log scale, and acidic stool pH (pH < 6) was found to be significantly associated with an increase in the fecal LCN-2 level by 0.89 units (95% CI: 0.12, 1.67; p < 0.025) in the log scale.

CONCLUSIONS

The study findings demonstrated an association of fecal pH with biomarkers of gut enteropathy indicating its applicability as a simple tool for understanding intestinal enteropathy among reproductive-age women living in resource-limited settings.

Combining pharmacometric models with predictive and prognostic biomarkers for precision therapy in Crohn's disease: A case study of brazikumab

Pharmacometric models were used to investigate the utility of biomarkers in predicting the efficacy (Crohn's Disease Activity Index [CDAI]) of brazikumab and provide a data-driven framework for precision therapy for Crohn's disease (CD). In a phase IIa trial in patients with moderate to severe CD, treatment with brazikumab, an anti-interleukin 23 monoclonal antibody, was associated with clinical improvement. Brazikumab treatment effect was determined to be dependent on the baseline IL-22 (BIL22) or baseline C-reactive protein (BCRP; predictive biomarkers), and placebo effect was found to be correlated with the baseline CDAI (a prognostic biomarker). A maximal total inhibition on CDAI input function of 50.6% and 42.4% was predicted for patients with extremely high BIL22 or BCRP, compared to a maximal total inhibition of 20.9% and 17.8% for patients with extremely low BIL22 or BCRP, respectively, which were mainly due to the placebo effect. We demonstrated that model-derived baseline biomarker levels that achieve 50% of maximum unbound systemic concentration of 22.8 pg/mL and 8.03 mg/L for BIL22 and BCRP as the cutoffs to select subpopulations can effectively identify high-response subgroup patients with improved separation of responders when compared to using the median values as the cutoff. This work exemplifies the utility of pharmacometrics to quantify biomarker-driven responses in biologic therapies and distinguish between predictive and prognostic biomarkers, complementing clinical efforts of identifying subpopulations with higher likelihood of response to brazikumab.

Development of a scoring system for predicting the severity of ulcerative colitis

BACKGROUND AND STUDY AIMS

Monitoring disease activity in ulcerative colitis (UC) is critical in preventing long-term complications. This study aims to develop a scoring system using non-invasive indicators to predict endoscopic activities for ulcerative colitis (UC) patients.

PATIENTS AND METHODS

All enrolled patients with UC admitted to Shanghai Xinhua Hospital between June 2017 and January 2021 were enrolled, and their clinical data were retrospectively collected and a number of serological biomarkers concentrations were analyzed. Patients were categorized into mild and moderate-to-severe disease groups. Univariate and multivariate logistic regression was used to predict moderate-to-severe endoscopic activities, which were then incorporated into a nomogram to establish a prediction scoring model.

RESULT

Overall, 231 patients were divided into a mild group (n = 111, 48.0%) and a moderate-to-severe group (n = 120, 52.0%). The following variables were independently associated with the disease severity and were subsequently included into the prediction model: Proteinase 3 antineutrophil cytoplasmic antibody (PR3-ANCA), C-reactive protein (CRP), hemoglobin(Hb), IL-10, stool frequency ≥ 5 times/day and hematochezia. Incorporating these 6 factors, the nomogram showed good discrimination with C-index of 0.819 and reliable calibration. A scoring model was established with the area under the curve 0.818. Moreover, PR3-ANCA and CRP correlated with the duration of hospital stay.

CONCLUSION

We developed a predictive model for endoscopic disease activities by using noninvasive factors based on PR3-ANCA, CRP, Hb, IL-10, stool frequency and hematochezia. This prediction model might assist clinicians in managing patients with UC.

Fecal acute phase proteins in cats with chronic enteropathies

BACKGROUND

Chronic enteropathies (CE) are common in cats and reliable biomarkers that can distinguish different causes and predict or monitor response to treatment are currently lacking.

HYPOTHESIS

To evaluate certain acute phase proteins in feces that could potentially be used as biomarkers in cats with CE.

ANIMALS

Twenty-eight cats with either inflammatory bowel disease (IBD; n = 13), food-responsive enteropathy (FRE; n = 3) or small cell gastrointestinal lymphoma (SCGL; n = 12) and 29 healthy control cats were prospectively enrolled.

METHODS

Fecal concentrations of haptoglobin, alpha-1-acid-glycoprotein (AGP), pancreatitis-associated protein-1 (PAP-1), ceruloplasmin, and C-reactive protein (CRP) were measured using Spatial Proximity Analyte Reagent Capture Luminescence (SPARCL) immunoassays before and after initiation of treatment. Cats were treated with diet and/or prednisolone (IBD cats), plus chlorambucil (SCGL cats).

RESULTS

Compared with controls, median fecal AGP concentrations were significantly lower (25.1 vs 1.8 μg/g; P = .003) and median fecal haptoglobin (0.17 vs 0.5 μg/g), PAP-1 (0.04 vs 0.4 μg/g) and ceruloplasmin (0.15 vs 4.2 μg/g) concentrations were significantly higher (P < .001) in cats with CE. Median fecal AGP concentrations were significantly lower (P = .01) in cats with IBD and FRE (0.6 μg/g) compared with cats with SCGL (10.75 μg/g). A significant reduction was found in CE cats after treatment for median fecal ceruloplasmin concentrations (6.36 vs 1.16 μg/g; P = .04).

CONCLUSIONS

Fecal AGP concentration shows promise to differentiate cats with SCGL from cats with IBD and FRE. Fecal ceruloplasmin concentrations may be useful to objectively monitor response to treatment in cats with CE.

Perceived Use Cases, Barriers, and Requirements for a Smart Health-Tracking Toilet Seat: Qualitative Focus Group Study

BACKGROUND

Smart bathroom technology offers unrivaled opportunities for the automated measurement of a range of biomarkers and other data. Unfortunately, efforts in this area are mostly driven by a technology push rather than market pull approach, which decreases the chances of successful adoption. As yet, little is known about the use cases, barriers, and desires that potential users of smart bathrooms perceive.

OBJECTIVE

This study aimed to investigate how participants from the general population experience using a smart sensor-equipped toilet seat installed in their home. The study contributes to answering the following questions: What use cases do citizens see for this innovation? and What are the limitations and barriers to its everyday use that they see, including concerns regarding privacy, the lack of fit with everyday practices, and unmet expectations for user experience?

METHODS

Overall, 31 participants from 30 households participated in a study consisting of 3 (partially overlapping) stages: sensitizing, in which participants filled out questionnaires to trigger their thoughts about smart bathroom use and personal health; provotyping, in which participants received a gentle provocation in the form of a smart toilet seat, which they used for 2 weeks; and discussion, in which participants took part in a web-based focus group session to discuss their experiences.

RESULTS

Participants mostly found the everyday use of the toilet, including installation and dismantling when necessary, to be relatively easy and free of complications. Where complications occurred, participants mentioned issues related to the design of the prototype, technology, or mismatches with normal practices in using toilets and hygiene. A broad range of use cases were mentioned, ranging from signaling potentially detrimental health conditions or exacerbations of existing conditions to documenting physical data to measuring biomarkers to inform a diagnosis and behavioral change. Participants differed greatly in whether they let others use, or even know about, the seat. Ownership and control over their own data were essential for most participants.

CONCLUSIONS

This study showed that participants felt that a smart toilet seat could be acceptable and effective, as long as it fits everyday practices concerning toilet use and hygiene. The range of potential uses for a smart toilet seat is broad, as long as privacy and control over disclosure and data are warranted.

Label-free microfluidic cell sorting and detection for rapid blood analysis

Blood tests are considered as standard clinical procedures to screen for markers of diseases and health conditions. However, the complex cellular background (>99.9% RBCs) and biomolecular composition often pose significant technical challenges for accurate blood analysis. An emerging approach for point-of-care blood diagnostics is utilizing "label-free" microfluidic technologies that rely on intrinsic cell properties for blood fractionation and disease detection without any antibody binding. A growing body of clinical evidence has also reported that cellular dysfunction and their biophysical phenotypes are complementary to standard hematoanalyzer analysis (complete blood count) and can provide a more comprehensive health profiling. In this review, we will summarize recent advances in microfluidic label-free separation of different blood cell components including circulating tumor cells, leukocytes, platelets and nanoscale extracellular vesicles. Label-free single cell analysis of intrinsic cell morphology, spectrochemical properties, dielectric parameters and biophysical characteristics as novel blood-based biomarkers will also be presented. Next, we will highlight research efforts that combine label-free microfluidics with machine learning approaches to enhance detection sensitivity and specificity in clinical studies, as well as innovative microfluidic solutions which are capable of fully integrated and label-free blood cell sorting and analysis. Lastly, we will envisage the current challenges and future outlook of label-free microfluidics platforms for high throughput multi-dimensional blood cell analysis to identify non-traditional circulating biomarkers for clinical diagnostics.

Predictive value of faecal calprotectin in ulcerative colitis - single centre experience

OBJECTIVES

Faecal calprotectin is an important biomarker used in the evaluation of inflammatory bowel disease. The aim of this study was to establish the value of faecal calprotectin concentration as a predictor of remission in ulcerative colitis and its correlation with laboratory, endoscopic and clinical findings.

METHODS

The single centre study included 126 adult patients with established diagnosis of ulcerative colitis consecutively visiting our Day clinic from March 2017 to March 2019. We measured serum biomarkers- CRP, haemoglobin, leukocytes and platelets. Faecal calprotectin was determined from stool, and endoscopy was performed with calculation of MAYO endoscopic subscore system (MES 0-1: remission, and MES 2-3: active disease). Clinical assessment was done by using Mayo score for ulcerative colitis (clinical Mayo score <2:remission, >5: active disease).The statistical analysis was performed using an univariate and multivariate model of disease remission prediction using logistic regression.

RESULTS

According to univariate analysis the increase of faecal calprotectin concentration by 10 ug/g is associated with an 8% decrease in probability of disease remission (OR 0.9921, p < .05). In the multivariate analysis, faecal calprotectin remained a significant predictor of disease remission (OR 0.9948, 95% CI 0.9914-0.9982, p = .0028), however, with a significant contribution of C-reactive protein (OR 0.8340, 95% CI 0.7085-0.9818, p = .0292). According to our model the cut off value for faecal calprotectin was 154 ug/g.

CONCLUSION

Our results have shown that faecal calprotectin is an independent predictor of remission in UC patients. The results of our study represent real-life data from a single university centre dealing with FC as a prognostic marker in patients with UC. KEY MESSAGESFaecal calprotectin is an independent predictor of remission in UC patients.Recent studies have suggested that calprotectin correlates well with endoscopic activity of inflammation but correlation of faecal calprotectin in a phase of remission hasn't been evaluated yet.We have found that other inflammatory biomarkers do not correlate well with either endoscopic or clinical activity in ulcerative colitis.

Comprehensive Phenotyping in Inflammatory Bowel Disease: Search for Biomarker Algorithms in the Transkingdom Interactions Context

Inflammatory bowel disease (IBD) is the most common form of intestinal inflammation associated with a dysregulated immune system response to the commensal microbiota in a genetically susceptible host. IBD includes ulcerative colitis (UC) and Crohn’s disease (CD), both of which are remarkably heterogeneous in their clinical presentation and response to treatment. This translates into a notable diagnostic challenge, especially in underdeveloped countries where IBD is on the rise and access to diagnosis or treatment is not always accessible for chronic diseases. The present work characterized, for the first time in our region, epigenetic biomarkers and gut microbial profiles associated with UC and CD patients in the Buenos Aires Metropolitan area and revealed differences between non-IBD controls and IBD patients. General metabolic functions associated with the gut microbiota, as well as core microorganisms within groups, were also analyzed. Additionally, the gut microbiota analysis was integrated with relevant clinical, biochemical and epigenetic markers considered in the follow-up of patients with IBD, with the aim of generating more powerful diagnostic tools to discriminate phenotypes. Overall, our study provides new insights into data analysis algorithms to promote comprehensive phenotyping tools using quantitative and qualitative analysis in a transkingdom interactions network context.

Association of fecal calprotectin level with eosinophilic gastrointestinal disease in Iranian pediatrics

Introduction

Fecal calprotectin (FC) is a noninvasive biomarker for assessing the inflammatory status of the gastrointestinal tract. The aim of this study was to determine the association between FC levels and Eosinophilic colitis (EC) before and after treatment in pediatrics.

Method

In this cross-sectional study, 330 patients with rectorrhagia and FC levels > 200 μg/g were included in the study. Patients were then subjected to colonoscopy, and if 30 or more eosinophils were observed in the pathology of at least two parts of the colon, EC was diagnosed. Of the 330 patients included in the study, 14 patients were diagnosed as EC. Treatment included seven food elimination diet (food allergens) for 3 months. After 3 months, FC levels were repeated and colonoscopy was performed.

Results

The mean age of the children was 5.9 years. After the elimination diet, the number of eosinophils in all segments of colon significantly decreased (P < 0.001) and according to the pathology report, the number of eosinophils improved in 42.9% of patients. Also, the mean number of segments involved in the colon of patients was significantly decreased (P < 0.001). Mean FC levels were significantly decreased after 3 months (P < 0.001). The cut-off point of 114 μg/g of FC had sensitivity (75%), specificity (67%), positive predictive value (75%), negative predictive value (67%), accuracy (71.4%), and area under the ROC curve (0.708) acceptable in predicting EC.

Conclusion

This study showed that FC levels can be elevated in patients with EC, which is easily corrected with a targeted elimination of food allergens.

The Current Status of Molecular Biomarkers for Inflammatory Bowel Disease

Diagnosis and prognosis of inflammatory bowel disease (IBD)-a chronic inflammation that affects the gastrointestinal tract of patients-are challenging, as most clinical symptoms are not specific to IBD, and are often seen in other inflammatory diseases, such as intestinal infections, drug-induced colitis, and monogenic diseases. To date, there is no gold-standard test for monitoring IBD. Endoscopy and imaging are essential diagnostic tools that provide information about the disease's state, location, and severity. However, the invasive nature and high cost of endoscopy make it unsuitable for frequent monitoring of disease activity in IBD patients, and even when it is possible to replace endoscopy with imaging, high cost remains a concern. Laboratory testing of blood or feces has the advantage of being non-invasive, rapid, cost-effective, and standardizable. Although the specificity and accuracy of laboratory testing alone need to be improved, it is increasingly used to monitor disease activity or to diagnose suspected IBD cases in combination with endoscopy and/or imaging. The literature survey indicates a dearth of summarization of biomarkers for IBD testing. This review introduces currently available non-invasive biomarkers of clinical importance in laboratory testing for IBD, and discusses the trends and challenges in the IBD biomarker studies.

Miconazole Mitigates Acetic Acid-Induced Experimental Colitis in Rats: Insight into Inflammation, Oxidative Stress and Keap1/Nrf-2 Signaling Crosstalk

Ulcerative colitis (UC) is the most common type of inflammatory bowel disease, characterized by oxidative stress and elevated pro-inflammatory cytokines. Miconazole is an azole antifungal that stimulates the expression of antioxidant enzymes via Nrf2 activation, which consequently inhibits ROS formation and NF-κB activation. Hence, the present study aimed to investigate the protective effect of miconazole, sulfasalazine (as a reference drug) and their combination on acetic acid (AA)-induced UC in a rat model which was induced by intra-rectal administration of 4% AA. Rats were pretreated with miconazole (20 and 40 mg/kg, orally) or sulfasalazine (100 mg/kg, orally), or their combination (20 mg/kg miconazole and 50 mg/Kg of sulfasalazine, orally). Pretreatment with miconazole significantly reduced wet colon weight and macroscopic scores, accompanied by a significant amelioration of the colonic architecture disorder. Moreover, the treatment also significantly decreased the malondialdehyde (MDA) level and prevented the depletion of superoxide dismutase (SOD) activity and GSH content in inflamed colons. Additionally, the treatment showed suppressive activities on pro-inflammatory cytokines, including tumor necrosis factor-α (TNF-α), interleukin-6 (IL-6) and C-reactive protein (CRP), and upregulated the anti-inflammatory cytokine interleukin-10 (IL-10). Moreover, the treatment upregulated the protein levels of Nrf-2 and heme oxygenase-1 (HO-1) in the colon tissue. Taken together, miconazole is effective in alleviating AA-induced colitis in rats, and the mechanism of its action is associated with the activation of Nrf2-regulated cytoprotective protein expression.

Serum indoxyl sulphate and its relation to albumin and α1-acid glycoprotein as a potential biomarkers of maternal intestinal metabolism during pregnancy and postpartum

Background

Serum indoxyl sulfate (IS) levels depend on the production of indole in the gut. The biological effects of IS in the vascular bed could be confirmed by changes in the levels of individual serum proteins during normal pregnancy and in the postpartum period as compared with non-pregnant controls. Albumin (Alb) and α₁-acid glycoprotein (AGP, orosomucoid) are the most abundant serum carrier proteins with potential interrelationships with serum levels of IS.

Methods

Serum levels of IS, Alb and AGP were measured in 84 pregnant women in the first, second and third trimester of pregnancy and in the postpartum period, as well as in non-pregnant controls (n = 20), using ultra-performance liquid chromatography (UPLC) coupled to mass spectrometry (IS), colorimetric assay (Alb) and immunoturbidimetric assay (AGP).

Results

The postpartum serum levels [mg/L] of IS were lower (p = 0.027) than in the second trimester (mean±SD: 0.85±0.39 vs 0.58±0.32). There were no differences in the IS to ALB ratio calculated in the three trimesters of pregnancy, the postpartum period, and in the non-pregnant controls. The IS/AGP ratio increased from the first to the second trimester (p = 0.039), and decreased in the postpartum period (p<0.05), when it was lower than in the second and third trimester.

Conclusions

The variability of the serum IS/AGP ratio during pregnancy and in the postpartum period may reflect shared involvement in the regulation of their intravascular relationships. The link between serum levels of IS derived from the gut and AGP could serve a potential biomarkers of maternal intestinal metabolism during pregnancy and postpartum.

Genetic Variants of DMBT1 and SFTPD and Disease Severity in Paediatric Inflammatory Bowel Disease—A Polish Population-Based Study

Deleted in malignant brain tumours 1 protein (DMBT1) and surfactant protein D (SFTPD) are antimicrobial peptides previously linked to inflammatory bowel disease (IBD) susceptibility. This study attempts to link the most potential IBD-associated polymorphisms in DMBT1 and SFTPD with the disease severity in children. A total of 406 IBD patients (Crohn’s disease (CD) n = 214 and ulcerative colitis (UC) n = 192) were genotyped using hydrolysis probe assay. Clinical expression was described by disease activity scales, albumin and C-reactive protein levels, localisation and behaviour (Paris classification), systemic steroid, immunosuppressive, biological, and surgical treatment, number of exacerbation-caused hospitalisations, relapses and nutritional status. IBD patients with the risk genotype (AA) in DMBT1 rs2981804 had more frequent biological treatment (AA: vs. AG/GG; p = 0.012), concomitant diseases (AA vs. AG vs. GG; p = 0.015) and cutaneous manifestations (AA vs. AG/GG, p = 0.008). In UC, rs2981804 genotypes might be linked with albumin concentrations at diagnosis (AA vs. AG vs. GG; p = 0.009). In CD, DMBT1 rs2981745 was significantly associated with the number of severe relapses per year of disease (p = 0.020) and time-to-immunosuppression (p = 0.045). SFTPD was seemingly found to be associated with age at first immunosuppression in IBD (CC vs. CT vs. TT; p = 0.048). In conclusion, selected polymorphisms of DMBT1 and SFTPD might be associated with some disease severity measures in children with IBD. However, the magnitude of associations and their clinical relevance might be minor.

Inflammatory Bowel Disease and Neutrophil-Lymphocyte Ratio: A Systematic Scoping Review

Neutrophil–lymphocyte ratio (NLR) is a biomarker of the systemic inflammatory response. The objective of this systematic scoping review was to examine the literature on NLR and inflammatory bowel disease (IBD). PubMed, Embase, Cochrane CENTRAL, CINAHL, ClinicalTrials.gov, Cochrane Specialized Register, DOAJ, PDQT, Biosis Citation Index, Scopus, and Web of Science were systematically searched. A total of 2621 citations yielding 62 primary studies were synthesized under four categories: distinguishing patients with IBD from controls, disease activity differentiation, clinical outcome prediction, and association of NLR with other IBD biomarkers. Thirty-eight studies employed receiver operating characteristic (ROC) curve analysis to generate optimal NLR cutpoints for applications including disease activity differentiation and prediction of response to treatment. Among the most promising findings, NLR may have utility for clinical and endoscopic disease activity differentiation and prediction of loss of response to infliximab (IFX). Overall findings suggest NLR may be a promising IBD biomarker. Assessment of NLR is non-invasive, low cost, and widely accessible given NLR is easily calculated from blood count data routinely and serially monitored in patients with IBD. Further research is justified to elucidate how evaluation of NLR in research and clinical practice would directly impact the quality and cost of care for patients living with IBD.

A literature review on large intestinal hyperelastic constitutive modeling

Impacts, traumas and strokes are spontaneously life-threatening, but chronic symptoms strangle patient every day. Colorectal tissue mechanics in such chronic situations not only regulates the physio-psychological well-being of the patient, but also confirms the level of comfort and post-operative clinical outcomes. Numerous uniaxial and multiaxial tensile experiments on healthy and affected samples have evidenced significant differences in tissue mechanical behavior and strong colorectal anisotropy across each layer in thickness direction and along the length. Furthermore, this study reviewed various forms of passive constitutive models for the highly fibrous colorectal tissue ranging from the simplest linearly elastic and the conventional isotropic hyperelastic to the most sophisticated second harmonic generation image based anisotropic mathematical formulation. Under large deformation, the isotropic description of tissue mechanics is unequivocally ineffective which demands a microstructural based tissue definition. Therefore, the information collected in this review paper would present the current state-of-the-art in colorectal biomechanics and profoundly serve as updated computational resources to develop a sophisticated characterization of colorectal tissues.

Utilizing machine learning with knockoff filtering to extract significant metabolites in Crohn's disease with a publicly available untargeted metabolomics dataset

Metabolomic data processing pipelines have been improving in recent years, allowing for greater feature extraction and identification. Lately, machine learning and robust statistical techniques to control false discoveries are being incorporated into metabolomic data analysis. In this paper, we introduce one such recently developed technique called aggregate knockoff filtering to untargeted metabolomic analysis. When applied to a publicly available dataset, aggregate knockoff filtering combined with typical p-value filtering improves the number of significantly changing metabolites by 25% when compared to conventional untargeted metabolomic data processing. By using this method, features that would normally not be extracted under standard processing would be brought to researchers’ attention for further analysis.

Effects of oral vitamin D supplementation on inflammatory bowel disease: a systematic review and meta-analysis

Vitamin D (VitD) is a fat-soluble micronutrient that plays a critical role in inflammatory bowel disease (IBD). Although the effective properties of VitD in anti-inflammatory and immune moderation were reviewed, some important issues still remain uncovered. Considering the practicability and high bioavailability, as a more recommended therapeutic approach, the effects of oral VitD supplementation on IBD remain inconclusive. This study aims to investigate the effect and safety of oral VitD supplementation on IBD patients, which has already been registered on PROSPERO (no. CRD42020165045). A pooled analysis of 17 trials with 1127 patients revealed that as a safety therapeutic strategy, oral VitD supplementation effectively increased the concentration of serum 25-hydroxyvitamin D [weighted mean difference 12.15 ng mL^-1; 95% confidence interval (CI) 9.26, 15.03; I² = 90%] and decreased serum C-reactive protein levels [standard mean difference (SMD) -0.33; 95% CI -0.61, -0.05; I² = 55%], but it did not decrease erythrocyte sedimentation rate levels (SMD 0.35; 95% CI -4.33, 5.03; I² = 57%), disease activity index (SMD -0.13; 95% CI -0.66, 0.39; I² = 84%) and relapse rate (RR 0.59; 95% CI 0.19, 1.86; I² = 79%). These findings suggest that oral VitD supplementation has a role to play in the therapeutic management of IBD. These findings may contribute to public health and clinical dietary guidelines and improve the health of IBD patients.

Accuracy of the highly sensitive C-reactive protein/albumin ratio to determine disease activity in inflammatory bowel disease

Persistent disease activity is associated with a poor prognosis in patients with inflammatory bowel disease (IBD). This study aims to explore the accuracy of the highly sensitive C-reactive protein/albumin ratio (CAR) in determining IBD activity.The clinical data of 231 IBD patients treated at Peking Union Medical College Hospital from 2012 to 2018 were analyzed retrospectively. The patients were classified as having active disease or remission according to the Crohn disease activity index scores for patients with Crohn disease (CD) and partial Mayo scores for patients with ulcerative colitis (UC).This study included 231 IBD patients (137 CD and 94 UC). From these groups, 182 patients had active disease, while 49 patients were in remission. The platelet counts, erythrocyte sedimentation rates, high-sensitivity C-reactive protein levels, and CAR scores were significantly higher, while hemoglobin levels, ALB, and body mass indexes were significantly lower in patients with active disease (P < 0.01). The hsCRP, CAR, and ALB significantly correlated with disease activity for both CD and UC (P < 0.001). The area under the curve (AUC) of CAR was highest among the laboratory indexes at 0.829, and the AUC of CAR in the UC patients was larger than that of the CD patients. Also, CAR with cutoff value of 0.06 displayed the highest sensitivity among the indexes for IBD activity at 83.05%.CAR is a useful biomarker for identifying disease activity in patients with CD and UC. Higher CAR levels are indicative of increased IBD activity. CAR may be more valuable in UC than that in CD for assessing the degree of IBD activity.

Prognostic tools for identification of high risk in people with Crohn's disease: systematic review and cost-effectiveness study

BACKGROUND

Crohn's disease is a lifelong condition that can affect any segment of the gastrointestinal tract. Some people with Crohn's disease may be at higher risk of following a severe course of disease than others and being able to identify the level of risk a patient has could lead to personalised management.

OBJECTIVE

To assess the prognostic test accuracy, clinical impact and cost-effectiveness of two tools for the stratification of people with a diagnosis of Crohn's disease by risk of following a severe course of disease.

DATA SOURCES

The data sources MEDLINE, EMBASE, the Cochrane Database of Systematic Reviews and the Cochrane Central Register of Controlled Trials were searched to inform the systematic reviews on prognostic accuracy, clinical impact of the prognostic tools, and economic evaluations. Additional data sources to inform the review of economic evaluations were NHS Economic Evaluation Database, Database of Abstracts of Reviews of Effects and the Health Technology Assessment Database.

REVIEW METHODS

Systematic reviews of electronic databases were carried out from inception to June 2019 for studies assessing the prognostic accuracy and clinical impact of the IBDX® (Crohn's disease Prognosis Test; Glycominds Ltd, Lod, Israel) biomarker stratification tool and the PredictSURE-IBD™ (PredictImmune Ltd, Cambridge, UK) tool. Systematic reviews of studies reporting on the cost-effectiveness of treatments for Crohn's disease were run from inception to July 2019. Two reviewers independently agreed on studies for inclusion, assessed the quality of included studies and validated the data extracted from studies. Clinical and methodological heterogeneity across studies precluded the synthesis of data for prognostic accuracy. A de novo economic model was developed to compare the costs and consequences of two treatment approaches - the 'top-down' and 'step-up' strategies, with step-up considered standard care - in people at high risk of following a severe course of Crohn's disease. The model comprised a decision tree and a Markov cohort model.

RESULTS

Sixteen publications, including eight original studies (n = 1478), were deemed relevant to the review of prognostic accuracy. Documents supplied by the companies marketing the prognostic tools were also reviewed. No study meeting the eligibility criteria reported on the sensitivity or specificity of the IBDX biomarker stratification tool, whereas one study provided estimates of sensitivity, specificity and negative predictive value for the PredictSURE-IBD tool. All identified studies were observational and were considered to provide weak evidence on the effectiveness of the tools. Owing to the paucity of data on the two tools, in the base-case analysis the accuracy of PredictSURE-IBD was assumed to be 100%. Accuracy of IBDX was assumed to be 100% in a scenario analysis, with the cost of the tests being the only difference between the analyses. The incremental analysis of cost-effectiveness demonstrated that top-down (via the use of PredictSURE-IBD in the model) is more expensive and generates fewer quality-adjusted life-years than step-up (via the standard care arm of the model).

LIMITATIONS

Despite extensive systematic searches of the literature, no robust evidence was identified of the prognostic accuracy of the biomarker stratification tools IBDX and PredictSURE-IBD.

CONCLUSIONS

Although the model indicates that standard care dominates the tests, the lack of evidence of prognostic accuracy of the two tests and the uncertainty around the benefits of the top-down and step-up treatment approaches mean that the results should be interpreted as indicative rather than definitive.

STUDY REGISTRATION

This study is registered as PROSPERO CRD42019138737.

FUNDING

This project was funded by the National Institute for Health Research (NIHR) Evidence Synthesis programme and will be published in full in Health Technology Assessment; Vol. 25, No. 23. See the NIHR Journals Library website for further project information.

Laboratory Assessment of Disease Activity in Pediatric Patients with Inflammatory Bowel Disease: What’s New?

Laboratory tests are an integral part of both the diagnostic and follow-up algorithm of patients with inflammatory bowel disease (IBD). Their advantages over other non-invasive methods for assessing disease activity are greater objectivity than clinical activity indices and imaging studies. This review aims to analyze shortly the most common laboratory tests used to assess disease activity in pediatric patients with IBD. In addition to the conventional blood and serum markers that are not specific for gut inflammation, although routinely used, we also reviewed the established fecal markers such as calprotectin, lactoferrin, M2-pyruvate kinase, osteoprotegerin, HMGB1, chitinase 3-like 1, and the promising non-coding microRNA. In conclusion, neither marker is unique to the pediatric IBD. More clinical data are required to assess biomarkers’ full potential for diagnosis, management, and follow-up of pediatric IBD patients.

Assessment of disease activity in inflammatory bowel diseases: Non-invasive biomarkers and endoscopic scores

Inflammatory bowel diseases (IBD) comprise two major forms: Crohn's disease and ulcerative colitis. The diagnosis of IBD is based on clinical symptoms combined with results found in endoscopic and radiological examinations. In addition, the discovery of biomarkers has significantly improved the diagnosis and management of IBD. Several potential genetic, serological, fecal, microbial, histological and immunological biomarkers have been proposed for IBD, and they have been evaluated for clinical routine and clinical trials. Ileocolonoscopy, especially with biopsy collection, has been considered the standard method to diagnose IBD and to assess clinical activity of the disease, but it is limited to the colon and terminal ileum and is considered invasive. For this reason, non-invasive biomarkers are necessary for this type of chronic inflammatory disease, which affects mostly young individuals, as they are expected to have a long follow-up.

Using serum peptidomics to discovery the diagnostic marker for different stage of ulcerative colitis

The use of peptidomics to find diagnostic markers has attracted increasing clinical attention. Ulcerative colitis (UC) is a type of inflammatory bowel disease, and the traditional auxiliary diagnostic technique is colonoscopy. However, this invasive method is not effective in distinguishing between patients with endoscopic remission and healthy people, which carries the risk of delayed diagnosis of UC. In this study, we used peptidomics to find serum diagnostic markers for different stages of UC. A total of 78 serum samples were collected to form a training set (60 samples) and a testing set (18 samples). Among them, patients with active UC, remitting UC and healthy people accounted for one third each. The nano-liquid chromatography coupled with hybrid linear trap quadrupole orbitrap mass spectrometry was used for detection of low molecular weight peptides in serum. According to the protein database search and de novo sequencing algorithm, forty peptides were simultaneously identified in all samples. Six biomarker peptides were screened in the training set through orthogonal partial least-squares-discriminant analysis and receiver operating characteristic curve analysis. These six peptides were derived from proteins involved in coagulation and complement activation. We evaluated the diagnostic ability of the six peptides in the testing set through hierarchical cluster analysis, and showed that perturbation of these peptides could distinguish patients with active UC, patients with remitting UC and healthy people. This study validated the feasibility of serum peptidomics for the discovery of diagnostic markers, and provided a potential method for diagnosing different stages of UC.

Biomarkers Suggesting Favorable Prognostic Outcomes in Sudden Sensorineural Hearing Loss

Sudden sensorineural hearing loss (SSNHL) is a medical emergency, making detailed examination to determine possible causes and early treatment important. However, etiological examinations in SSNHL do not always reveal a cause, and several factors have been found to affect treatment outcomes. Various studies are being performed to determine the prognosis and effects of treatment in patients who experience sudden hearing loss, and to identify biomarkers associated with this condition. Embase, PubMed, and the Cochrane database were searched using the key words SSNHL, prognostic, and biomarker. This search identified 4 articles in Embase, 28 articles in PubMed, and 36 in the Cochrane database. Of these 68 articles, 3 were duplicates and 37 were unrelated to the research topic. After excluding these articles, the remaining 28 articles were reviewed. Factors associated with SSNHL were divided into six categories: metabolic, hemostatic, inflammatory, immunologic, oxidative, and other factors. The associations between these factors with the occurrence of SSNHL and with patient prognosis were analyzed. Low monocyte counts, low neutrophil/lymphocyte ratio (NLR) and monocyte/high-density lipoproteins (HDL) cholesterol ratio (MHR), and low concentrations of fibrinogen, platelet glycoprotein (GP) IIIa, and TNF-α were found to be associated with good prognosis. However, these factors alone could not completely determine the onset of and recovery from SSNHL, suggesting the need for future basic and clinical studies.

CpG Methylation in TGFβ1 and IL-6 Genes as Surrogate Biomarkers for Diagnosis of IBD in Children

BACKGROUND

Diagnostic markers for distinguishing between Crohn disease (CD) and ulcerative colitis (UC) remain elusive. We studied whether methylation marks across the promoters of the transforming growth factor beta 1 (TGFβ1) and interleukin-6 genes have diagnostic utility.

METHODS

A case-control study was carried out. Cases were treatment-naïve, diagnosed before age 20, and recruited from 3 pediatric gastroenterology clinics across Canada. Control patients did not have inflammatory bowel disease and were recruited from orthopedic clinics within the same hospitals as the gastroenterology clinics. Patient DNA from peripheral blood was processed to identify methylation sites (CpG) across the promoter regions of the TGFβ1 and interleukin-6 genes. After initial nonparametric univariate analyses, multivariate logistic regression models were fit. Models with the best fit (Akaike information criteria) and strongest discriminatory capabilities (area under the curve [AUC]) were identified, and P values were adjusted for multiple comparisons using the false discovery rate method.

RESULTS

A total of 67 CD, 31 UC, and 43 control patients were included. The age distribution of the 3 groups was similar. Most CD patients had ileocolonic disease (44.8%) and inflammatory disease (88.1%). Most UC patients had extensive (71%) and moderate disease (51.6%). Logistic regression analysis revealed the following: 14 TGFβ1 CpG sites discriminated between CD and control patients (AUC = 0.94), 9 TGFβ1 CpG sites discriminated between UC and control patients (AUC = 0.99), 3 TGFβ1 CpG sites discriminated between CD and UC (AUC = 0.81), and 6 TGFβ1 CpG sites distinguished colonic CD from UC (AUC = 0.91).

CONCLUSIONS

We found that CpG methylation in the promoter of the TGFβ1 gene has high discriminative power for identifying CD and UC and could serve as an important diagnostic marker.

Recent Advances in Smart Biomaterials for the Detection and Treatment of Autoimmune Diseases

Autoimmune diseases are a group of debilitating illnesses that are often idiopathic in nature. The steady rise in the prevalence of these conditions warrants new approaches for diagnosis and treatment. Stimuli-responsive biomaterials also known as "smart", "intelligent" or "recognitive" biomaterials are widely studied for their applications in drug delivery, biosensing and tissue engineering due to their ability to produce thermal, optical, chemical, or structural changes upon interacting with the biological environment. This critical analysis highlights studies within the last decade that harness the recognitive capabilities of these biomaterials towards the development of novel detection and treatment options for autoimmune diseases.

Biomarkers of Crohn's Disease to Support the Development of New Therapeutic Interventions

BACKGROUND

Currently, 2 coprimary end points are used by health authorities to determine the effectiveness of therapeutic interventions in patients with Crohn's disease (CD): symptomatic remission (patient-reported outcome assessment) and endoscopic remission (ileocolonoscopy). However, there is lack of accepted biomarkers to facilitate regulatory decision-making in the development of novel therapeutics for the treatment of CD.

METHODS

With support from the Helmsley Charitable Trust, Critical Path Institute formed the Crohn's Disease Biomarkers preconsortium (CDBpC) with members from the pharmaceutical industry, academia, and nonprofit organizations to evaluate the CD biomarker landscape. Biomarkers were evaluated based on biological relevance, availability of biomarker assays, and clinical validation data.

RESULTS

The CDBpC identified the most critical need as pharmacodynamic/response biomarkers to monitor disease activity in response to therapeutic intervention. Fecal calprotectin (FC) and serum C-reactive protein (CRP) were identified as biomarkers ready for the regulatory qualification process. A number of exploratory biomarkers and potential panels of these biomarkers was also identified for additional development. Given the different factors involved in CD and disease progression, a combination of biomarkers, including inflammatory, tissue injury, genetic, and microbiome-associated biomarkers, will likely have the most utility.

CONCLUSIONS

The primary focus of the Inflammatory Bowel Disease Regulatory Science Consortium will be development of exploratory biomarkers and the qualification of FC and CRP for IBD. The Inflammatory Bowel Disease Regulatory Science Consortium, focused on tools to support IBD drug development, will operate in the precompetitive space to share data, biological samples for biomarker testing, and assay information for novel biomarkers.

Role of regenerating islet-derived proteins in inflammatory bowel disease

Inflammatory bowel disease (IBD) is an inflammatory disorder of the gastrointestinal tract that affects millions of patients worldwide. It has a complex and multifactorial etiology leading to excessive exposure of intestinal epithelium to microbial antigens, inappropriate activation of the immune system and ultimately to the damage of intestinal tissues. Although numerous efforts have been made to improve the disease management, IBD remains persistently recurring and beyond cure. This is due largely to the gaps in our understanding of the pathogenesis of IBD that hamper the development of timely diagnoses and effective treatment. However, some recent discoveries, including the beneficial effects of interleukin-22 (IL-22) on the inflamed intestine, have shed light on a self-protective mechanism in IBD. Regenerating islet-derived (REG/Reg) proteins are small secretory proteins which function as IL-22's downstream effectors. Mounting studies have demonstrated that IBD patients have significantly increased REG expressions in the injured intestine, but with undefined mechanisms and roles. The reported functions of REG/Reg proteins in intestinal homeostasis, such as those of antibacterial, anti-inflammatory and tissue repair, lead us to discuss their potential mechanisms and clinical relevance in IBD in order to advance IBD research and management.

Additional Candida albicans administration enhances the severity of dextran sulfate solution induced colitis mouse model through leaky gut-enhanced systemic inflammation and gut-dysbiosis but attenuated by Lactobacillus rhamnosus L34

is abundant in the human gut mycobiota but this species does not colonize the mouse gastrointestinal tract. C. albicans administration in dextran-sulfate solution (DSS) induced-colitis mouse model (DSS+Candida) might resemble more to human condition, therefore, a DSS colitis model with Candida administration was studied; first, to test the influence of fungi in DSS model and second, to test the efficacy of Lactobacillus rhamnosus L34. We demonstrated serum (1→3)-β-D-glucan (BG) elevation in patients with IBD and endoscopic moderate colitis in clinical remission, supporting the possible influence of gut fungi toward IBD in human. Then, in mouse model, Candida gavage was found to worsen the DSS model indicated by higher mortality rate, more severe colon histology and enhanced gut-leakage (FITC-dextran assay, endotoxemia, serum BG and blood bacterial burdens) but did not affect weight loss and diarrhea. DSS+Candida induced higher pro-inflammatory cytokines both in blood and in intestinal tissue. Worsened systemic pro-inflammatory cytokine responses in DSS+Candida compared with DSS alone was possibly due to the more severe translocation of LPS, BG and bacteria (not fungemia) from gut into systemic circulation. Interestingly, bacteremia from Pseudomonas aeruginosa was more frequently isolated from DSS+Candida than DSS alone. In parallel, P. aeruginosa was also isolated from fecal culture in most of the mice in DSS+Candida group supported by prominent Gammaproteobacteria in fecal microbioata analysis. However, L. rhamnosus L34 attenuated both DSS+Candida and DSS model through the attenuation of gut local inflammation (cytokines and histology), gut-leakage severity, fecal dysbiosis (culture method and microbiome analysis) and systemic inflammation (serum cytokines). In conclusion, gut Candida in DSS model induced fecal bacterial dysbiosis and enhanced leaky-gut induced bacteremia. Probiotic treatment strategy aiming to reduce gut-fungi and fecal dysbiosis could attenuate disease severity. Investigation on gut fungi in patients with IBD is highly interesting.

Diagnostic utility of the neutrophil-platelet ratio as a novel marker of activity in patients with Ulcerative Colitis

Background

Ulcerative colitis (UC) is a chronic disease characterized by periods of activity and remission. The platelet, one of the main activators of neutrophils, contains Interleukin 8 (IL-8), a potent neutrophil chemo-attractant and P-selectin that induces excretion of superoxide in the neutrophils, forming platelet-neutrophil aggregates that are increased in individuals with active UC, hence an index of both cells could produce a monitoring tool. No previous studies have evaluated this ratio in UC.

Goal

To evaluate the clinical utility of the Neutrophil-Platelet (NeuPla) ratio in patients with UC.

Study

A total of 158 patients with a diagnosis of UC. This index was based on the ratio between platelets and the neutrophil differential in blood count. The activity was classified using Mayo endoscopic sub-score, histological (Riley score) and for clinical was used the Truelove-Witts, Montreal, Mayo and Yamamoto-Furusho scores.

Results

The correlation of the NeuPla ratio with activity scales were significant (P <0.05). An optimal cut-off point to classify patients with clinical activity was 14.94 with a sensitivity 87.95% and specificity 63.5 and endoscopy activity with a cut-off 14.64 with a sensibility of 70.5% and specificity of 61.8%.

Conclusions

The NeuPla ratio showed an adequate diagnostic utility to identify UC patients with clinical and endoscopy activity without the use of invasive studies like a colonoscopy or expensive fecal biomarkers such as calprotectin and have a better diagnostic performance in comparison to other serum biomarkers (C reactive protein, erythrocyte sedimentation rate and albumin).

Proteomic insights on the metabolism in inflammatory bowel disease

Inflammatory bowel diseases (IBD) are chronic and relapsing inflammatory conditions of the gut that include Crohn's disease and ulcerative colitis. The pathogenesis of IBD is not completely unraveled, IBD are multi-factorial diseases with reported alterations in the gut microbiota, activation of different immune cell types, changes in the vascular endothelium, and alterations in the tight junctions’ structure of the colonic epithelial cells. Proteomics represents a useful tool to enhance our biological understanding and to discover biomarkers in blood and intestinal specimens. It is expected to provide reproducible and quantitative data that can support clinical assessments and help clinicians in the diagnosis and treatment of IBD. Sometimes a differential diagnosis of Crohn's disease and ulcerative colitis and the prediction of treatment response can be deducted by finding meaningful biomarkers. Although some non-invasive biomarkers have been described, none can be considered as the “gold standard” for IBD diagnosis, disease activity and therapy outcome. For these reason new studies have proposed an “IBD signature”, which consists in a panel of biomarkers used to assess IBD. The above described approach characterizes “omics” and in this review we will focus on proteomics.

Evaluation of Small-Bowel Patency in Crohn's Disease: Prospective Study with a Patency Capsule and Computed Tomography

Background and Purpose

Patency capsule (PC) examination is usually performed - previously to capsule endoscopy - to evaluate small-bowel patency in patients with established Crohn's disease (CD). The reported PC retention rate is significantly higher than expected. Our aims were to assess small-bowel patency, to determine the precise location of the retained PC in patients with CD, and to determine the false positive rate of evaluation with a radiofrequency identification tag (RFIT) scanner.

Methods

This is a prospective single-center study including CD patients with clinical indication for small-bowel capsule endoscopy. PillCam® PC examination was performed on all patients to assess small-bowel patency. On all patients with a positive identification of the PC using an RFIT scanner, 30 h after ingestion, an abdominal CT was performed in order to identify its precise location.

Results

Fifty-four patients were included. The PC retention rate, according to evaluation with the RFIT scanner, was 20% (in 11 patients) 30 h after ingestion. These patients were then submitted to abdominal CT, which revealed that there was small-bowel retention in 5 cases (9%). Higher CRP levels, penetrating disease, and a history of abdominal surgery were associated with an increased risk of PC retention (p = 0.007, p = 0.011, and p = 0.033, respectively). On multivariate analysis, there was an independent association between small-bowel PC retention and CRP levels >5 mg/dL (OR = 15.5; p = 0.03).

Discussion

The small-bowel PC retention rate (9%) was considerably lower than those found in previous reports. Our results show that, with this protocol, the false-positive cases of RFIT scans or plain abdominal X-rays may be avoided. This may contribute to more extensive application of capsule endoscopy without the risk of small-bowel retention.

Lemann Index for Assessment of Crohn's Disease: Correlation with the Quality of Life, Endoscopic Disease Activity, Magnetic Resonance Index of Activity and C- Reactive Protein

Aim

Crohn's disease (CD) is characterized by continuing inflammation and progressive gut damage. Despite many scoring indices of CD, there is a lack of more global assessment tools for the evaluation of the total disease impact on the gut.

Methods

Fift y-three adult patients with proven CD underwent magnetic resonance enterocolonography (MR-EC), colonoscopy, and clinical activity assessment, including CRP. Quality of life was assessed using IBDQ. MR-EC was used to evaluate the Magnetic Resonance Index of Activity (MaRIA- global (G)) and the Lemann Index (LI). The CD Endoscopic Index of Severity (CDEIS) was used to score the endoscopic activity of the disease.

Results

A signifi cant correlation between the LI and IBDQ was found (r=-0.812, P<0.01). LI and MaRIA-G correlated moderately, while the LI did not correlate significantly with CRP and CDEIS. For the detection of endoscopically active CD, MaRIA-G was more sensitive and specific (83.3%; 73.3%) compared to the LI (66.7%; 60.0%). There was a moderate correlation between CRP and MaRIA-G, as well as CRP and CDEIS (r=0.496; r=0.527,<0.01).

Conclusion

A signifi cant negative correlation between the LI and quality of life, measured by IBDQ, was found in our study, suggesting that the LI could resemble more global features of the disease, besides inflammatory activity of the gut.

A Novel Predictor Parameter for Active Recurrent Aphthous Stomatitis: C-Reactive Protein to Albumin Ratio

Objective

Laboratory analysis results may provide an opportunity to predict the activity process of recurrent aphthous stomatitis. The goal of this study was to investigate whether there is a correlation between C-reactive protein to albumin ratio (CAR) and oral ulcer activity in patients with recurrent aphthous stomatitis.

Materials and methods

We included 72 patients (39 with active and 33 with inactive lesion) with recurrent aphthous stomatitis and 60 healthy controls. We compared blood test parameters including CAR, white blood cell count (WBC) and neutrophil to lymphocyte ratio (NLR) among the groups. Additionally, we investigated the most significant parameter for the activity of oral ulcers.

Results

NLR was significantly higher both in the active (p<0.001) and inactive lesion groups (p<0.001), compared to the control group but did not significantly differ between active and inactive lesion groups (p=0.17). A significant difference in median CAR (p<0.001) and WBC (p<0.001) was evident among the three groups. Median WBC was significantly higher in the active lesion group compared to the control group (p<0.001) but did not significantly differ between active and inactive lesion groups (p=0.095). Median CAR was significantly higher in the active lesion group, compared both to the inactive lesion group (p=0.002) and the control group (p<0.001). Median CAR was also significantly higher in the inactive lesion group compared to the control group (p<0.001). Median hemoglobin, platelet to lymphocyte ratio and mean platelet volume did not significantly differ among three groups (p=0.16, p=0.85, p=0.19, respectively).

Conclusion

CAR could be used as a predictive parameter for inflammation and activity of oral ulcers in patients with recurrent aphthous stomatitis.

Serum MMP-9: a novel biomarker for prediction of clinical relapse in patients with quiescent Crohn's disease, a post hoc analysis

BACKGROUND

Matrix metalloproteinase-9 (MMP-9) is a novel marker of intestinal inflammation. The aim of this study was to assess if serum MMP-9 levels predict clinical flare in patients with quiescent Crohn's disease (CD).

METHODS

This study was a post hoc analysis of a prospective observational study in which quiescent CD patients were included and followed until clinical relapse or the end of a 2-year follow-up period. Serial C-reactive protein (CRP) and fecal calprotectin (FC) levels were measured, and the patients underwent repeated capsule endoscopies (CEs) every 6 months. Small bowel inflammation was quantified by Lewis score (LS) for CE. A baseline magnetic resonance enterography was also performed, and MaRIA score was calculated. Serum MMP-9 levels in baseline blood samples were quantified by ELISA.

RESULTS

Out of 58 eligible enrolled patients, 16 had a flare. Higher levels of baseline MMP-9 were found in patients who developed subsequent symptomatic flare compared with patients who did not [median 661 ng/ml, 25-75 interquartile range (IQR; 478.2-1441.3) versus 525.5 ng/ ml (339-662.7), respectively, p = 0.01]. Patients with serum MMP-9 levels of 945 ng/ ml or higher were at increased risk for relapse within 24 months [area under the curve (AUC) of 0.72 [95% confidence interval (CI): 0.56-0.88]; hazard ratio 8.1 (95% CI 3.0-21.9, p < 0.001)]. Serum MMP-9 concentrations showed weak and moderate correlation to baseline LS and FC, respectively (r = 0.31, p = 0.02; r = 0.46, p < 0.001). No correlation was found between serum MMP-9 to CRP and MaRIA score.

CONCLUSIONS

Serum MMP-9 may be a promising biomarker for prediction of clinical flare in CD patients with quiescent disease.

The value of mRNA expression of S100A8 and S100A9 as blood-based biomarkers of inflammatory bowel disease

BACKGROUND AND STUDY AIMS

Non-invasive biomarkers of inflammatory bowel diseases (IBD) are of critical importance. Here, we evaluated the S100A8 and S100A9 mRNA expression, as the heterodimers of calprotectin, in the blood leucocytes of IBD patients to find how their expression associates with the disease characteristics.

PATIENTS AND METHODS

In this cross-sectional study, 59 IBD patients and 30 healthy subjects were included. The flare and remission phases of disease were identified in 46 and 13 patients, respectively. Blood leucocytes were isolated, and the S100A8 and S100A9 mRNA expression were evaluated in the isolated leucocytes using relative quantification real-time PCR.

RESULTS

The mean S100A8 and S100A9 mRNA expression were significantly higher in IBD patients than in the controls (p = 0.03 and p = 0.02, respectively). The mean S100A8 and S100A9 mRNA expression were significantly higher in the flare phase of the disease compared with the remission phase (p = 0.01 and p = 0.007, respectively). S100A8 distinguished IBD patients from controls with the sensitivity and specificity of 73% and 64%, and flare phase of disease from remission with the sensitivity and specificity of 67% and 62%. On the other hand, S100A9 distinguished IBD patients from controls with the sensitivity and specificity of 81% and 70%, and flare phase of disease from remission with the sensitivity and specificity of 68% and 64%.

CONCLUSION

The S100A8 and S100A9 mRNA are differentially expressed in blood leucocytes of IBD patients compared to healthy controls as well as active versus quiescent disease. Thus, they can be potentially used as a blood-based biomarker in the monitoring of IBD.

Clinical Usefulness of Proteomics in Inflammatory Bowel Disease: A Comprehensive Review

The protein domain is probably the most ubiquitously affected in disease, response and recovery, and therefore proteomics holds special promise for biomarker discovery in general, and particularly in inflammatory bowel disease [IBD], i.e. ulcerative colitis and Crohn's disease. Tremendous progress has been made over the past decade in the development and refinement of proteomics technologies. These advances provide opportunities for a long-anticipated personalized medicine approach to the treatment of IBD. The present review examines the current state of IBD proteomics research and its usefulness in clinical practice. We performed a systematic bibliographic search to identify studies investigating the use of proteomics in patients with IBD, and we then summarized the current 'state of the art' in the applications of proteomic technologies in the study of IBD. In particular, in the present review we provide: [1] a brief introduction to proteomics in health and disease; [2] a review of the different stages from biomarker discovery to clinical application; and [3] a comprehensive review of the clinical usefulness and application of proteomics in IBD, including: [a] screening to differentiate IBD from healthy controls; [b] differentiating Crohn's disease from ulcerative colitis; [c] prediction of the behaviour or the IBD course; [d] prediction of IBD response to biological treatment; and [e] monitoring response to treatment. We also review the importance of the type of sample-blood vs intestinal tissue-for the study of proteomics in IBD patients. Finally, we emphasize the current limitations of proteomic studies in IBD.

Integrative analysis of Paneth cell proteomic and transcriptomic data from intestinal organoids reveals functional processes dependent on autophagy

Paneth cells are key epithelial cells that provide an antimicrobial barrier and maintain integrity of the small-intestinal stem cell niche. Paneth cell abnormalities are unfortunately detrimental to gut health and are often associated with digestive pathologies such as Crohn's disease or infections. Similar alterations are observed in individuals with impaired autophagy, a process that recycles cellular components. The direct effect of autophagy impairment on Paneth cells has not been analysed. To investigate this, we generated a mouse model lacking Atg16l1 specifically in intestinal epithelial cells, making these cells impaired in autophagy. Using three-dimensional intestinal organoids enriched for Paneth cells, we compared the proteomic profiles of wild-type and autophagy-impaired organoids. We used an integrated computational approach combining protein-protein interaction networks, autophagy-targeted proteins and functional information to identify the mechanistic link between autophagy impairment and disrupted pathways. Of the 284 altered proteins, 198 (70%) were more abundant in autophagy-impaired organoids, suggesting reduced protein degradation. Interestingly, these differentially abundant proteins comprised 116 proteins (41%) that are predicted targets of the selective autophagy proteins p62, LC3 and ATG16L1. Our integrative analysis revealed autophagy-mediated mechanisms that degrade key proteins in Paneth cell functions, such as exocytosis, apoptosis and DNA damage repair. Transcriptomic profiling of additional organoids confirmed that 90% of the observed changes upon autophagy alteration have effects at the protein level, not on gene expression. We performed further validation experiments showing differential lysozyme secretion, confirming our computationally inferred downregulation of exocytosis. Our observations could explain how protein-level alterations affect Paneth cell homeostatic functions upon autophagy impairment.

This article has an associated First Person interview with the joint first authors of the paper.

Editor's choice: Using an integrative approach encompassing intestinal organoid culture, proteomics, transcriptomics and protein-protein interaction networks, we list Paneth cell functions dependent on autophagy.

Elevated urinary orosomucoid excretion as a novel biomarker in Crohn's disease

BACKGROUND

Laboratory markers are essential tools in the follow-up of patients with Crohn's disease (CD). Our aim was to investigate urinary concentrations of orosomucoid in relation to the inflammatory activity of CD and to compare it with clinical indices and conventional laboratory parameters.

MATERIALS AND METHODS

Blood and urine samples of 86 patients (55 adults and 31 children) with CD and 68 healthy individuals (38 adults and 30 children) as controls were analysed. Patients were categorized according to their clinical scores (Harvey-Bradshaw Index [HBI] or Pediatric Crohn's Disease Activity Index [PCDAI]). Urinary orosomucoid (u-ORM) was determined by automated immune turbidimetric assay, and values were referred to urinary creatinine (u-ORM/u-CREAT, mg/mmol).

RESULTS

U-ORM/u-CREAT values were seven times higher in children with active CD (0.50 vs 0.07 mg/mmol, P < 0.001) and two times higher in adults (0.32 vs 0.14 mg/mmol, P = 0.01) compared with patients with inactive disease. U-ORM/u-CREAT showed good correlation with conventional inflammatory markers (hs-CRP, serum ORM; P < 0.01) and activity indices (HBI, P = 0.018; PCDAI, P < 0.001). U-ORM/u-CREAT had similar discriminative performance to hs-CRP and serum ORM in the differentiation of active from inactive paediatric CD patients.

CONCLUSIONS

Our findings suggest that u-ORM/u-CREAT might serve as a valuable additional marker in the follow-up of CD patients, especially in children for whom the non-invasive sampling is a further advantage.