Serum Calprotectin: A Novel Diagnostic and Prognostic Marker in Inflammatory Bowel Diseases

Identification of S100A9 as a target for diagnosis and treatment of Crohn's Disease after Vedolizumab treatment failure

The vedolizumab medication is the treatment that precisely targets the gut for Crohn's Disease (CD). It can inhibit the migration of lymphocytes to the intestinal site despite the fact that a significant portion of the population continues to be ineffectively treated. In this study, peripheral blood leukocytes sampled from the CD patients who are nonresponsive or responsive to vedolizumab treatment were used for transcriptome sequencing. Intersected differentially expressed mRNA obtained from transcriptome sequencing and GSE191328 were utilized to predict key therapeutic targets. Bioinformatics analyses were used to explore potential biological mechanisms and to screen pivotal genes. Inhibitor of S100A9 increased the body weight and colon length of mice with colitis, and decreased the DAI score. Our study also demonstrated that the combination of anti-α4β7 integrin antibody with inhibitor of S100A9 further alleviates colitis. Through flow cytometry, changes in the composition of immune cell populations in colon tissues were found after intragastric administration of paquinimod, an inhibitor of S100A9. It is important that blocking S100A9 inhibited the recruitment of neutrophils in the mice's colon. Our findings lay a foundation for the further exploration of the new targets for non-responders to vedolizumab in CD patients.

Structure-Affinity Relationship Analysis and Affinity Maturation of a Calprotectin-Binding Peptide

Peptide 3 is an 18-amino acid linear peptide binding with sub-micromolar affinity to the inflammation marker calprotectin. Its application in point-of-care diagnostic assays has shown promising results, yet improving its affinity for calprotectin could facilitate the development of sensitive and robust assays. Herein, a detailed structure-activity relationship analysis of Peptide 3 is reported to better understand the importance of each individual amino acid for the binding to calprotectin. Moreover, two different approaches have been followed here, one based on prolonging the peptide with random sequences and phage display selection, and one on screening chemically synthesized peptide variants containing non-canonical amino acids, to increase its binding affinity. Combining several mutations that enhance affinity by small factors yielded Peptide 4 binding human calprotectin with a KD of 39 ± 5 nM measured by surface plasmon resonance spectroscopy, which is a five-fold improvement compared to the previously reported Peptide 3.

Plasma bile acid profile analysis by liquid chromatography-tandem mass spectrometry and its application in healthy subjects and IBD patients

Bile acids (BAs), not only promote the absorption of fat-soluble nutrients and regulate the metabolism of multiple substances but also have a potential role as diagnostic and prognostic indicators in a variety of diseases such as cholestasis, hepatocellular carcinoma, and diabetes mellitus. Here, a rapid and sensitive liquid chromatography-tandem mass spectrometry (LC-MS/MS) method for the simultaneous quantification of 50 BAs was developed and validated. Sample preparation included internal standard spiking, followed by protein precipitation, centrifugation, solvent evaporation, and reconstitution. Baseline separation of all isobaric BA species was achieved on an Ultimate XS-C18 column (5 μm, 150 mm × 4.6 mm). The method showed good linearity with high regression coefficients (>0.990) with acceptable accuracy and precision for intra-day and inter-day analyses and achieved good recovery rates for representative analytes. No apparent carryover or matrix effect was observed. The analytical method was successfully applied to the determination of the plasma BA profile in healthy subjects and patients with inflammatory bowel disease (IBD). The routine instrumentation, low sample volume, simple pretreatment, wide range of BAs, and good separation make this LC-MS/MS method suitable for use as a BA profile assay in clinical and basic research studies. This method could be poised to identify possible BA biomarkers for non-invasive early diagnosis and therapeutic evaluation of IBD.

The diagnostic accuracy of plasma and serum calprotectin is inferior to C-reactive protein in patients with suspected Crohn's disease

BACKGROUND AND AIMS

Prior studies indicate that serum calprotectin (SC) and plasma calprotectin (PC) can be used as biomarkers in Crohn's disease (CD). The aim of this study was to investigate the diagnostic accuracy of SC and PC in patients with a clinical suspicion of CD.

METHOD

This biobank study included patients from a prospective, blinded, multicenter study examining minimally invasive modalities for diagnosing CD. Patients had a standardized work-up including ileocolonoscopy, pan-enteric capsule endoscopy, and blood samples within a 2-week period. Plasma and serum were stored at - 80 °C until further analysis. A routine C-reactive protein (CRP) was measured on the same day. Pan-endoscopy served as reference standard.

RESULTS

126 patients entered the study, and 58 (46.0%) were diagnosed with CD. Patients with CD had a median PC of 0.37 mg/L (IQR 0.20-0.70) compared to 0.29 mg/L (IQR 0.16-0.41) in non-CD patients (p = 0.03). The median SC was 1.09 mg/L (IQR 0.80-1.80) and 0.93 mg/L (IQR 0.66-1.25), respectively (p = 0.01). Receiver operating characteristics curves showed an AUC of 0.63 (CI 0.53-0.73) for SC and 0.61 (CI 0.51-0.71) for PC for detection of CD, which was inferior to that of CRP (AUC = 0.76, CI 0.68-0.85) (p < 0.02). None of the biomarkers reflected the endoscopic severity of CD.

CONCLUSION

Although levels of PC and SC are elevated in patients with CD, diagnostic accuracies are inferior to CRP. SC and PC are not reliable as stand-alone blood-based biomarkers for diagnosing CD and selecting patients for endoscopy.

Fecal and Serum Calprotectin Concentrations in Cats With Chronic Enteropathies Before and During Treatment

Background

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

Hypothesis/Objectives

Evaluate calprotectin concentrations in serum and feces as potential biomarkers in cats with CE.

Animals

Forty‐three cats with either chronic inflammatory enteropathy (CIE; n = 25) or small cell gastrointestinal lymphoma (SCGL; n = 18) and 36 healthy cats were prospectively enrolled.

Methods

Fecal and serum calprotectin concentrations were determined before and during treatment. Cats with CIE were treated with diet, prednisolone, or diet and prednisolone, and cats with SCGL were treated with prednisolone plus chlorambucil with or without diet.

Results

Compared to controls, fecal calprotectin concentration was significantly higher in cats with CE (median, ≤ 161 ng/g; range, ≤ 161–2827 vs. median, ≤ 161 ng/g; range, ≤ 161–790; p = 0.01). No significant differences were found in fecal (median ≤ 161 ng/g; range, ≤ 161–1920 vs. median, 189 ng/g; range, ≤ 161–2827; p = 0.3) or serum calprotectin (median, ≤ 1291 mg/L; range, ≤ 1291–15 358 vs. median, ≤ 1291 mg/L; range, ≤ 1291–6422; p = 0.99) between cats with CIE and cats with SCGL. Fecal calprotectin was significantly decreased after treatment in cats with CE (median, ≤ 161 ng/g; range, ≤ 161–1897 vs. median, ≤ 161 ng/g; range, ≤ 161–656; p = 0.02).

Conclusions

Fecal calprotectin concentration might be a good biomarker for diagnosis and treatment monitoring for a subset of cats with CE. Serum calprotectin concentrations do not seem to be useful for diagnosis or treatment monitoring in cats with CE. Neither fecal nor serum calprotectin concentrations could differentiate cats with CIE from cats with SCGL.

Plasma calprotectin as a biomarker of inflammatory activity in ulcerative colitis

BACKGROUND

An ideal test to evaluate the inflammatory burden in ulcerative colitis is still an unmet need. Fecal calprotectin (FCP) and C-reactive protein (CRP) have significant limitations. Plasma calprotectin (PC) seems to be promising in inflammatory diseases, but its value in IBD is still to be determined. Our aim was to assess whether PC correlates with inflammatory activity in UC.

METHODS

Prospective single center cohort study. Consecutive patients previously diagnosed with UC undergoing endoscopy were included (June 2021-September 2022). Demographic, clinical, analytical (CRP, PC and FCP), endoscopic and histologic data was collected at the time of colonoscopy. PC was assessed with Gentian Calprotectin Immunoassay and, in a subgroup of patients, also with QUANTA Flash Circulating Calprotectin from INOVA.

RESULTS

Inclusion of 98 patients (60.2% male) with a median age 49 (38-61) years. The extent of colitis was distal in 12 (12.2%), left-sided in 49 (50%), and extensive in 37 (37.8%). Mesalazine was taken by 65 (66.3%) patients, with biologic monotherapy used in 24 (24.5%) and combination therapy in 6 (6.1%). Clinical, endoscopic and histological remission were detected, in 56 (57.1%), 48 (49%) and in 55 (56.1%) patients, respectively. Comparing MES 0/1 vs MES 2/3, a statistically significant difference was found with PC, CRP and FCP. Concerning endoscopic (MES=1) and histological (GS<2) remission, FCP was the only biomarker able to detect these outcomes. PC (Gentian) and PCi (INOVA) were highly correlated with CRP.

CONCLUSION

PC has low value in distinguishing patients in remission from patients with endoscopic or histologic activity in UC. This essential role must continue be played by FCP.

The Role of Calprotectin in the Diagnosis and Treatment of Inflammatory Bowel Disease

The management of inflammatory bowel disease (IBD), which is characterized by immunodeficiency, has attracted increasing attention, highlighting the necessity for more precise and streamlined diagnostic approaches in clinics. Calprotectin, an immune cell-derived protein with inherent anti-inflammatory and antimicrobial properties, plays a pivotal role in immune regulation and intestinal homeostasis. Its expression levels are intricately linked to IBD activity, enabling differentiation between inflammatory and non-inflammatory states while predicting recurrence risks. As a non-invasive biomarker, fecal calprotectin (FC) and serum calprotectin (SC) analysis offers high reproducibility and clinical utility, facilitating both IBD diagnosis and real-time disease monitoring. Beyond its diagnostic specificity in distinguishing IBD from other gastrointestinal disorders, calprotectin also emerges as a promising therapeutic target, due to its dual role in modulating inflammatory pathways and interacting with the gut microbiota. With collaborative advancements in standardized detection protocols and innovative research methodologies, it is anticipated that calprotectin-based strategies will be integrated into mainstream clinical practice for IBD.

Deficient SARS-CoV-2 hybrid immunity during inflammatory bowel disease

Patients with Inflammatory Bowel Disease (IBD) undergoing immunosuppressive therapies face heightened susceptibility to severe COVID-19. An in-depth understanding of systemic inflammation and cellular immune responses after SARS-CoV-2 vaccination and breakthrough infections (BTI) is required for optimizing vaccine strategies in this population. While the prevalence of high serological responders post- third COVID-19 vaccine dose was lower, and the antibody waning was higher in IBD patients than in healthy donors (HD), IBD patients showed an increase in anti-RBD Wild Type IgG levels and cross-reactive Spike -specific memory B cells following BTI. However, there was no significant enhancement in cellular immune responses against anti-SARS-CoV-2 post-BTI, with responses instead characterized by activation of SARS-CoV-2 specific and also bystander CD8 T cells. These results suggest a complex interaction between chronic inflammation in IBD and the generation of new immune responses, highlighting the need for tailored vaccine regimens and anti-inflammatory therapies to boost cellular immunity against SARS-CoV-2.

Plasma Concentration of Calprotectin, but Not Serum Concentration, Is a Predictive Biomarker for Clinical Remission in Ulcerative Colitis

Introduction

Fecal calprotectin is a validated biomarker for assessing disease activity in patients with inflammatory bowel disease (IBD). Blood calprotectin concentrations are correlated with disease activity in numerous immune-mediated inflammatory diseases. The aim of this study was to prospectively assess the diagnostic accuracy of plasma calprotectin as a potential biomarker of remission in IBD patients.

Methods

This prospective observational study enrolled 131 patients at the time of infliximab administration alongside clinical assessment and blood analyses on the same day. The primary endpoint was to assess the diagnostic accuracy of plasma calprotectin for predicting remission in patients with IBD.

Results

Plasma calprotectin concentration ≤10.5 ng/mL had a sensitivity of 98.6%, specificity of 100%, positive predictive value of 100%, negative predictive value of 96.3%, and an area under the receiver operating characteristic (AUROC) curve of 0.999 for diagnosing remission in patients with ulcerative colitis (UC). Plasma calprotectin had poor diagnostic accuracy for diagnosing remission in Crohn's disease. In UC, plasma calprotectin had significantly greater diagnostic accuracy than C-reactive protein for diagnosing remission (absolute difference between AUROCs, 0.06; 95% CI: 0.008 to 0.113; p = 0.03). Plasma calprotectin concentrations were not correlated with those measured in serum samples. The median serum-to-plasma calprotectin concentration ratio was 12-fold.

Conclusion

Plasma calprotectin is a promising biomarker for predicting remission in UC patients treated with infliximab.

Heterozygous BTNL8 variants in individuals with multisystem inflammatory syndrome in children (MIS-C)

Multisystem inflammatory syndrome in children (MIS-C) is a rare condition following SARS-CoV-2 infection associated with intestinal manifestations. Genetic predisposition, including inborn errors of the OAS-RNAseL pathway, has been reported. We sequenced 154 MIS-C patients and utilized a novel statistical framework of gene burden analysis, "burdenMC," which identified an enrichment for rare predicted-deleterious variants in BTNL8 (OR = 4.2, 95% CI: 3.5-5.3, P < 10-6). BTNL8 encodes an intestinal epithelial regulator of Vγ4+γδ T cells implicated in regulating gut homeostasis. Enrichment was exclusive to MIS-C, being absent in patients with COVID-19 or bacterial disease. Using an available functional test for BTNL8, rare variants from a larger cohort of MIS-C patients (n = 835) were tested which identified eight variants in 18 patients (2.2%) with impaired engagement of Vγ4+γδ T cells. Most of these variants were in the B30.2 domain of BTNL8 implicated in sensing epithelial cell status. These findings were associated with altered intestinal permeability, suggesting a possible link between disrupted gut homeostasis and MIS-C-associated enteropathy triggered by SARS-CoV-2.

Fecal and Serum Granulocyte Protein Levels in Inflammatory Bowel Disease and Irritable Bowel Syndrome and Their Relation to Disease Activity

INTRODUCTION

Neutrophilic calprotectin (CP) and myeloperoxidase (MPO), neutrophil gelatinase-associated lipocalin (NGAL), and eosinophil-derived neurotoxin (EDN) are suggested proxy markers for gut inflammation. However, there are insufficient supporting data for MPO, NGAL, and EDN.

METHODS

In a cross-sectional investigation including adult patients, we studied the ability of CP, MPO, NGAL, and EDN, measured in fecal and serum samples, to differentiate between inflammatory bowel disease (IBD) and irritable bowel syndrome (IBS), and to predict disease activity.

RESULTS

Fifty-nine patients had ulcerative colitis (UC), 38 had Crohn's disease, and 100 patients had IBS. The protein concentrations were higher in patients with IBD in the fecal samples ( P < 0.001) and the serum samples ( P < 0.01), and they correlated weakly (r s ≤0.38) between the sample sources. Fecal EDN was higher in patients with Crohn's disease compared with UC (1.79 vs 0.50 mg/kg, P = 0.016). The neutrophilic proteins were superior to EDN in the fecal samples for differentiating between patients with IBD and IBS. Fecal MPO (cutoff: 0.86 mg/kg) had the highest sensitivity (74.7%) and specificity (84.6%). Combining fecal CP and MPO increased the sensitivity to 82.3% (specificity: 73.6%). NGAL (cutoff: 196.9 μg/L) showed the best discriminating performance in serum (sensitivity: 62.9%; specificity: 68.0%). Serum NGAL (cutoff: 272.4 μg/L) predicted active disease in UC (Partial Mayo Score ≥2) with a sensitivity and specificity of 57.1% and 83.3%, respectively.

DISCUSSION

Fecal MPO and serum NGAL are promising novel biomarkers, in addition to fecal CP, for differentiating between IBD and IBS. Serum NGAL may also predict disease activity in patients with UC.

A (poly)phenol-rich diet reduces serum and faecal calprotectin in older adults with increased intestinal permeability: the MaPLE randomised controlled trial

BACKGROUND

Older subjects are at risk of elevated intestinal permeability (IP) which can lead to immune system activation and low-grade systemic inflammation. Dietary changes are a potential strategy to reduce IP. The MaPLE project evaluated the hypothesis that increasing (poly)phenol intake would beneficially impact on several important markers and pathways related to IP. The objective of the present study was to assess the effects of the MaPLE (poly)phenol-rich diet (PR-diet) on additional IP-related biomarkers and any relationships between biomarker responses.

METHODS

A randomised, controlled, crossover study was performed involving 51 participants (≥ 60 y) with increased IP, as determined by serum zonulin levels. Participants were randomly assigned to one of two intervention groups: a control diet (C-diet) or a PR-diet. Each intervention lasted 8 weeks and was separated by an 8-week washout period. For the present study, serum and faecal samples were used to measure zonula occludens-1 (ZO-1), occludin, adiponectin, calprotectin, faecal calprotectin, soluble cluster of differentiation 14 (sCD14), interleukin-6 receptor (IL-6R), and vascular endothelial-cadherin (VEC) levels using quantitative ELISA assays. Data were analysed using ANOVA, and Spearman and network correlation analysis were performed to identify the relationship among biomarkers at baseline.

RESULTS

Among the different markers analysed, a significant reduction was observed for faecal and serum calprotectin (p = 0.0378 and p = 0.0186, respectively) following the PR-diet, while a significant increase in ZO-1 was found (p = 0.001) after both the intervention periods (PR-diet and C-diet). In addition, a time effect was observed for VEC levels showing a reduction (p = 0.038) following the PR-diet. Based on network correlation analysis, two clusters of correlations were identified: one cluster with high levels of serum calprotectin, faecal calprotectin, sCD14, interleukin (IL)-6, tumor necrosis factor (TNF)-α, C-reactive protein (CRP) and bacterial DNAemia (16 S rRNA gene copies), with potential inflammatory-induced intestinal permeability. Differently, the other cluster had high levels of serum occludin, IL-6R, soluble intercellular adhesion molecule-1 (sICAM-1) and VEC, with potential inflammatory-induced endothelial dysfunction.

CONCLUSIONS

Overall, this study provides further support to the hypothesis that a (poly)phenol-rich diet may help to ameliorate intestinal permeability-associated conditions. In this regard, calprotectin might represent a promising biomarker since it is a protein that typically increases with age and it is considered indicative of intestinal and systemic inflammation. Further research is needed to develop targeted (poly)phenol-rich diets against age-related gut dysfunction and inflammation.

TRIAL REGISTRATION

28/04/2017; ISRCTN10214981; https://doi.org/10.1186/ISRCTN10214981 .

Role of serum calprotectin in identifying familial Mediterranean fever attacks

BACKGROUND/AIM

The aim of the study was to evaluate serum calprotectin (CLP) levels in familial Mediterranean fever (FMF) patients and to investigate the utility of CLP in distinguishing patients with attack from patients without attack.

MATERIAL AND METHOD

FMF patients, rheumatoid arthritis (RA) patients, and healthy controls were included. Serum calprotectin levels were quantified utilizing the enzyme-linked immunosorbent assay (ELISA) method. Receiver operating characteristic (ROC) curve analysis was used to identify the cut-off value of serum CLP level to differentiate FMF patients with attack from those without. Logistic regression analysis was performed to identify predictors.

RESULTS

Significant differences were observed among the three groups concerning white blood cell (WBC), neutrophil, erythrocyte sedimentation rate (ESR), C-reactive protein (CRP), and serum CLP levels (p = 0.003, p = 0.004, p < 0.001, p < 0.001, and p = 0.002, respectively). Higher ESR, CRP, and serum CLP levels were observed in FMF patients with attacks than those without (all, p < 0.001). Serum CLP was significantly higher in RA patients than in FMF patients in remission (p < 0.001). ROC analysis identified a threshold CLP concentration in FMF with an attack to be 47.1 pg/mL (83.3% sensitivity, 60.6% specificity, AUC = 0.74, 95% CI = 0.63-0.85, p < 0.001). In univariate logistic regression analysis, CLP (β = 1.045, 95% CI = 1.017-1.073, p = 0.001) was predictive of FMF patients experiencing an attack.

CONCLUSION

Serum CLP proves to be as productive as ESR in illustrating inflammation and demonstrating the existence of attacks in FMF patients.

Development of Luminescent Biosensors for Calprotectin

Calprotectin, a metal ion-binding protein complex, plays a crucial role in the innate immune system and has gained prominence as a biomarker for various intestinal and systemic inflammatory and infectious diseases, including inflammatory bowel disease (IBD) and tuberculosis (TB). Current clinical testing methods rely on enzyme-linked immunosorbent assays (ELISAs), limiting accessibility and convenience. In this study, we introduce the Fab-Enabled Split-luciferase Calprotectin Assay (FESCA), a novel quantitative method for calprotectin measurement. FESCA utilizes two new fragment antigen binding proteins (Fabs), CP16 and CP17, that bind to different epitopes of the calprotectin complex. These Fabs are fused with split NanoLuc luciferase fragments, enabling the reconstitution of active luciferase upon binding to calprotectin either in solution or in varied immobilized assay formats. FESCA's output luminescence can be measured with standard laboratory equipment as well as consumer-grade cell phone cameras. FESCA can detect physiologically relevant calprotectin levels across various sample types, including serum, plasma, and whole blood. Notably, FESCA can detect abnormally elevated native calprotectin from TB patients. In summary, FESCA presents a convenient, low-cost, and quantitative method for assessing calprotectin levels in various biological samples, with the potential to improve the diagnosis and monitoring of inflammatory diseases, especially in at-home or point-of-care settings.

Serum Calprotectin in the Evaluation of Gastrointestinal Diseases: An Ace up Your Sleeve?

Background: Calprotectin (CP) is a calcium- and zinc-binding protein that plays a key role in innate immunity and in the recruitment of inflammatory cells. CP can be detected both in serum and in fecal samples. Serum CP (sCP) is more specific for autoimmune diseases, while fecal CP (fCP) has been well investigated for gastrointestinal diseases. Few studies have shown the clinical effectiveness of sCP as an acute-phase biomarker for gastrointestinal diseases. Aim: The aim of this narrative review is to discuss the role of sCP as a useful alternative biomarker of the acute-phase activity of gastrointestinal diseases and as a possible tool for screening and monitoring these diseases. Material and Methods: We searched original articles, abstracts, reviews, case reports, and clinical trials on PubMed®, Up-to-Date®, and Medscape® in the last ten years. Conclusion: We found that sCP could represent a useful biomarker in the evaluation of the inflammatory stage in patients with immune-mediated gastrointestinal diseases, but more studies are needed to promote its routine use in clinical practice as a diagnostic and prognostic biomarker as a replacement for fCP.

Research progress of autoimmune diseases based on induced pluripotent stem cells

Autoimmune diseases can damage specific or multiple organs and tissues, influence the quality of life, and even cause disability and death. A 'disease in a dish' can be developed based on patients-derived induced pluripotent stem cells (iPSCs) and iPSCs-derived disease-relevant cell types to provide a platform for pathogenesis research, phenotypical assays, cell therapy, and drug discovery. With rapid progress in molecular biology research methods including genome-sequencing technology, epigenetic analysis, '-omics' analysis and organoid technology, large amount of data represents an opportunity to help in gaining an in-depth understanding of pathological mechanisms and developing novel therapeutic strategies for these diseases. This paper aimed to review the iPSCs-based research on phenotype confirmation, mechanism exploration, drug discovery, and cell therapy for autoimmune diseases, especially multiple sclerosis, inflammatory bowel disease, and type 1 diabetes using iPSCs and iPSCs-derived cells.

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.

Influence of the gut microbiome on appetite-regulating neuropeptides in the hypothalamus: Insight from conventional, antibiotic-treated, and germ-free mouse models of anorexia nervosa

Recent research highlights the profound impact of the gut microbiome on neuropsychiatric disorders, shedding light on its potential role in shaping human behavior. In this study, we investigate the role of the gut microbiome in appetite regulation using activity-based anorexia (ABA) mouse model of anorexia nervosa (AN) - a severe eating disorder with significant health consequences. ABA was induced in conventional, antibiotic-treated, and germ-free mice. Our results show the clear influence of the gut microbiome on the expression of four orexigenic (neuropeptide Y, agouti-related peptide, melanin-concentrating hormone, and orexin) and four anorexigenic peptides (cocaine- and amphetamine-regulated transcript, corticotropin-releasing hormone, thyrotropin-releasing hormone, and pro-opiomelanocortin) in the hypothalamus. Additionally, we assessed alterations in gut barrier permeability. While variations were noted in germ-free mice based on feeding and activity, they were not directly attributable to the gut microbiome. This research emphasizes that the gut microbiome is a pivotal factor in AN's appetite regulation beyond just dietary habits or physical activity.

Establishing a pediatric reference interval for plasma calprotectin

Plasma calprotectin is a promising new biomarker of inflammatory activity and has been found to correlate well with clinical and endoscopic activity in children and adolescents with inflammatory bowel disease. A pediatric reference interval for plasma calprotectin has not been established for the Phadia 250 EliA™ Calprotectin fluoroenzyme immunoassay. In studies regarding pre-analytical properties, excellent precision and stability was found. However, sensitivity to hemolysis was demonstrated. We identified pediatric blood samples from apparently healthy children who were referred by their general practitioner for blood sampling including measurement of hemoglobin (Hb) and C-reactive protein (CRP). We excluded samples from children who had undergone additional blood sampling within 2 months before or after the index sample, if Hb was outside of local reference ranges or CRP levels were above the lower limit of the measuring interval (LLM), and any samples with a hemolysis above 0.02 mmol/L. Using this algorithm, we identified 141 blood samples. No outliers were identified. We established the following reference intervals according to CLSI C28-A3 using non-parametric statistics: 1-17 years: 16-246 µg/L. Our results may prove useful for further utilization of plasma calprotectin as a marker of inflammation in children and adolescents with inflammatory disorders.

Biomarkers and predictors of postoperative necrotizing enterocolitis in neonates with duct-dependent congenital heart defects undergoing cardiac surgery: a cohort study

The development of necrotizing enterocolitis (NEC) in neonates with duct-dependent congenital heart defects (CHD) who underwent cardiac surgery is accompanied by high mortality. Analysis of predictors is necessary for understanding the pathophysiology of NEC and development of approaches for prevention to achieve favorable outcomes of cardiac surgery. The purpose of the study was to develop a prognostic model for predicting the development of NEC after cardiac surgery in neonates with duct-dependent CHD. Methods. A prognostic cohort study was performed that included full-term neonates with duct-dependent CHD who underwent cardiac surgery at the Almazov National Medical Research Center from January 2021 to September 2023. The outcome was the development/absence of stage IB-III NEC in the postoperative period. Biomarkers of NEC (intestinal fatty acid binding protein (i-FABP, ng/ml), claudin-3 (CLDN3, ng/ml), calprotectin (CALPR, ng/ml), ischemia modified albumin (IMA, ng/ml), vascular endothelial growth factor A (VEGF A, pg/ml)) were measured by ELISA in the blood serum before cardiac surgery and 12-14 hours after surgery. We also analyzed clinical characteristics of neonates, C-reactive protein levels, complete blood count, abdominal ultrasound, ejection fraction (EF, Teicholtz) in the preoperative and postoperative periods, surgical parameters, P(v-a)CO2/C(a-v)O2 upon arrival from the operating room, vasoactive inotropic score (VIS) and arterial blood lactate levels in the first 24 hours after surgery. The association between predictors and the development of NEC after cardiac surgery was assessed using univariate and multivariate logistic regression analysis. Internal validation of the model was performed using 10-fold cross-validation. Results. During the observation period, 187 neonates underwent surgical treatment of duct-dependent CHD, of which 32 children developed stage IB-III NEC in the postoperative period (17.1%), two neonates required surgical treatment of NEC (6.3%). After meeting the non-inclusion and exclusion criteria, two groups of patients were formed: a main group (30 neonates who developed stages IB-III NEC in the postoperative period, of which stage III NEC was in one neonate) and a comparison group (40 neonates without NEC). Groups were comparable by types of CHD. Predictors associated with NEC (univariate analysis): intrauterine growth retardation (IUGR), formula feeding before surgery, high levels of IMA before on the first postoperative day (POD), procedures performed before surgery (Rashkind procedure/valvuloplasty/stenting), lower EF in in the early postoperative period, a higher maximum level of VIS in the first 24 hours after surgery, as well as a higher level of IR in the superior mesenteric artery (SMA) and thickening of the intestinal wall on the first postoperative day (POD) Independent preoperative predictors of NEC (AUC of model 0.885, specificity 0.867): IUGR (OR 32.2 (1.4-730.3), p=0.029), formula feeding (OR 12.6 (2.6-60.2), p=0.002), IMA level before surgery (OR 1.03 (1.01-1.04), p=0.004), CLDN3 level before surgery (OR 0.5 (0.3-0.9), p=0.013). Independent early postoperative predictors of NEC: IMA level on 12-14 hour after surgery (OR 1.02 (1.01-1.03), p=0.030), P(v-a)CO2/C(a-v)O2 immediately after surgery (OR 2.3 (1.2-4.4), p=0.008), IR>0.93 in SMA (OR 7.2 (1.6-32.4), p=0.011) and thickness of intestinal wall by ultrasound on POD 1 (OR 4.9 (1.3-19.2), p=0.021). Adding of VEGF A level (12-14 hour after surgery, negatively associated with NEC) to the model increased the specificity, but the predictor was not significant. AUC of postoperative model 0.862, specificity 0.800. The final model included preoperative (IUGR, formula feeding) and postoperative predictors (IMA, P(v-a)CO2/C(a-v)O2, IR of SMA>0.93, intestinal wall thickness), AUC=0.921, specificity 0.83. Conclusion. The identified predictors indirectly indicate the role of hypoxia in the pathophysiology of NEC in term neonates with duct-dependent CHD. Breast milk feeding/mixed feeding in the preoperative period may help reduce the risk of NEC in the postoperative period. Low levels of CLDN3 before surgery were associated with the development of NEC, but the interpretation of the result is controversial.

Biomarkers prediction and immune landscape in ulcerative colitis: Findings based on bioinformatics and machine learning

BACKGROUND

Ulcerative colitis (UC) presents diagnostic and therapeutic difficulties. The primary objective of this study is to identify efficacious biomarkers for diagnosis and treatment, as well as acquire a deeper understanding of the immuneological characteristics associated with the disease.

METHODS

Datasets relating to UC were obtained from GEO database. Among these, three datasets were merged to create a metadata for bioinformatics analysis and machine learning. Additionally, one dataset specifically utilized for external validation. Least absolute shrinkage and selection operator (LASSO) and random forest (RF) were employed to screen signature genes. The artificial neural network (ANN) model and receiver operating characteristic (ROC) curve were used to assess the diagnostic performance of signature genes. The single sample gene set enrichment analysis (ssGSEA) was applied to reveal the immune landscape. Finally, the relationship between the signature genes, immune infiltration, and clinical characteristics was investigated through correlation analysis.

RESULT

By intersecting the result of LASSO, RF and WGCNA, 8 signature genes were identified, including S100A8, IL-1B, CXCL1, TCN1, MMP10, GREM1, DUOX2 and SLC6A14. The biological progress of this gene mostly encompasses acute inflammatory response, aggregation and chemotaxis of leukocyte, and response to lipopolysaccharide by mediating IL-17 signaling pathway, NF-kappa B signaling pathway, TNF signaling pathway, NOD-like receptor signaling pathway. Immune infiltration analysis shows 25 immune cells are significantly elevated in UC samples. Moreover, these signature genes exhibit a strong correlation with various immune cells and a mild to moderate correlation with the Mayo score.

CONCLUSION

S100A8, IL-1B, CXCL1, TCN1, MMP10, GREM1, DUOX2 and SLC6A14 have been identified as credible potential biomarkers for the diagnosis and therapy of UC. The immune response mediated by these signature biomarkers plays a crucial role in the occurrence and advancement of UC by means of the reciprocal interaction between the signature biomarkers and immune-infiltrated cells.

Determination of the relationships between serum amyloid A, serum calprotectin and fecal calprotectin in healthy and infectious diarrheic calves and their diagnostic significances as inflammatory markers

In this study, serum amyloid A (SAA), serum calprotectin (SCalp) and fecal calprotectin (FCalp) levels were investigated in neonatal calves with infectious diarrhea. Total of 70 calves were divided into E. coli, C. parvum, C. parvum + viral, viral and control groups. Clinical parameters were recorded on days 0 and 7, post treatment. On these days, blood and stool samples were also taken. SAA, SCalp and FCalp levels were measured with commercial ELISA kits. Mean SAA levels on day 0 were measured as 0.54 (0.16-2.18) ng/ml and 38.40 (8.28-83.96) ng/ml for the diarrhea and healthy group, respectively (P < 0.001). Statistically significant difference was also obtained between the diarrhea [68.02 ng/ml 46.66-101.67] and control [24.05 ng/ml 11.92-56] groups in terms of SCalp levels on day 0 (P < 0.001). Cut-off value of SCalp to distinguish E. coli originated diarrhea from viral diarrhea was found to be 70.969 ng/ml (Sens: 94%). FCalp levels on day 0 were 93.08 (22.17-122.88) ng/ml and 87.01 ± 3.33 ng/ml in the diarrhea and healthy groups, respectively (P = 0.04). Cut-off concentration of FCalp was found to be 91.804 ng/ml (P = 0.0057). In addition, as a result of the logistic regression analysis, FCalp's ability to identify animals with diarrhea was found to be 6.316 times (P = 0.009) higher. The highest levels of SCalp and FCalp measured on day 0 were found among E. coli group. As a result, the importance of FCalp and SCalp in diagnosing the status of infectious diarrhea in calves for the first time in the veterinary literature is emphasized.

Bacillus coagulans GBI-30, 6086 (BC30) improves lactose digestion in rats exposed to a high-lactose meal

PURPOSE

Bacillus coagulans GBI-30, 6086 (BC30) was previously shown to improve nutrient digestibility and amino acid absorption from milk protein in vitro. However, the effect of supplementation with this probiotic on lactose digestibility has not yet been evaluated in vivo.

METHODS

Wistar female rats were exposed to an acute high-lactose diet (LD; 35% lactose) meal challenge after 7 days of administration of BC30 (LD-BC; n = 10) or vehicle (LD-C; n = 10). Rats treated with vehicle and exposed to control diet (CD; 35% corn starch) meal were used as controls (CD-C; n = 10). Carbohydrate oxidation (CH_OX) and lipid oxidation (L_OX) were monitored by indirect calorimetry before and after lactose challenge. After the challenge, rats were treated daily with vehicle or probiotic for an additional week and were fed with CD or LD ad libitum to determine the effects of BC30 administration in a lactose-induced diarrhoea and malnutrition model.

RESULTS

LD-C rats showed lower CH_OX levels than CD rats, while LD-BC rats showed similar CH_OX levels compared to CD rats during the lactose challenge, suggesting a better digestion of lactose in the rats supplemented with BC30. BC30 completely reversed the increase in the small intestine length of LD-C animals. LD-BC rats displayed increased intestinal mRNA Muc2 expression. No significant changes were observed due to BC30 administration in other parameters, such as serum calprotectin, intestinal MPO activity, intestinal A1AT and SGLT1 levels or intestinal mRNA levels of Claudin2 and Occludin.

CONCLUSION

Treatment with BC30 improved the digestibility of lactose in an acute lactose challenge and ameliorated some of the parameters associated with lactose-induced malnutrition.

Current and emerging biomarkers for ulcerative colitis

INTRODUCTION

Ulcerative colitis (UC) is a chronic illness requiring lifelong management that could be enhanced by personalizing care using biomarkers.

AREAS COVERED

The main biomarker discovery modalities are reviewed, highlighting recent results across the spectrum of applications, including diagnostics (serum anti-αvβ6 antibodies achieving an area under the curve [AUC] = 0.99; serum oncostatin M AUC = 0.94), disease activity assessment (fecal calprotectin and serum trefoil factor 3: AUC > 0.90), prognostication of the need for treatment escalation (whole blood transcriptomic panels and CLEC5A/CDH2 ratio: AUC > 0.90), prediction of treatment response, and early identification of patients with subclinical disease. The use of established biomarkers is discussed, along with new evidence regarding autoantibodies, proteins, proteomic panels, transcriptomic signatures, deoxyribonucleic acid methylation patterns, and UC-specific glycomic and metabolic disturbances.

EXPERT OPINION

Novel biomarkers will pave the way for optimized UC care. However, validation, simplification, and direct clinical translation of complex models may prove challenging. Currently, few candidates exist to assess key characteristics, such as UC susceptibility, histological disease activity, drug response, and long-term disease behavior. Further research will likely not only reveal new tools to tackle these issues but also contribute to understanding UC pathogenesis mechanisms.

Predictive risk markers in alcoholism

The medical disorders of alcoholism rank among the leading public health problems worldwide and the need for predictive and prognostic risk markers for assessing alcohol use disorders (AUD) has been widely acknowledged. Early-phase detection of problem drinking and associated tissue toxicity are important prerequisites for timely initiations of appropriate treatments and improving patient's committing to the objective of reducing drinking. Recent advances in clinical chemistry have provided novel approaches for a specific detection of heavy drinking through assays of unique ethanol metabolites, phosphatidylethanol (PEth) or ethyl glucuronide (EtG). Carbohydrate-deficient transferrin (CDT) measurements can be used to indicate severe alcohol problems. Hazardous drinking frequently manifests as heavy episodic drinking or in combinations with other unfavorable lifestyle factors, such as smoking, physical inactivity, poor diet or adiposity, which aggravate the metabolic consequences of alcohol intake in a supra-additive manner. Such interactions are also reflected in multiple disease outcomes and distinct abnormalities in biomarkers of liver function, inflammation and oxidative stress. Use of predictive biomarkers either alone or as part of specifically designed biological algorithms helps to predict both hepatic and extrahepatic morbidity in individuals with such risk factors. Novel approaches for assessing progression of fibrosis, a major determinant of prognosis in AUD, have also been made available. Predictive algorithms based on the combined use of biomarkers and clinical observations may prove to have a major impact on clinical decisions to detect AUD in early pre-symptomatic stages, stratify patients according to their substantially different disease risks and predict individual responses to treatment.

Calprotectin in Patients with Rheumatic Immunomediated Adverse Effects Induced by Checkpoints Inhibitors

BACKGROUND

this is an exploratory study to evaluate calprotectin serum levels in patients with rheumatic immune-related adverse events (irAEs) induced by immune checkpoint inhibitor (ICI) treatment.

METHODS

this is a retrospective observational study including patients with irAEs rheumatic syndromes. We compared the calprotectin levels to those in a control group of patients with RA and with a control group of healthy individuals. Additionally, we included a control group of patients treated with ICI but without irAEs to check calprotectin levels. We also analysed the performance of calprotectin for the identification of active rheumatic disease using receiver operating characteristic curves (ROC).

RESULTS

18 patients with rheumatic irAEs were compared to a control group of 128 RA patients and another group of 29 healthy donors. The mean calprotectin level in the irAE group was 5.15 μg/mL, which was higher than the levels in both the RA group (3.19 μg/mL) and the healthy group (3.81 μg/mL) (cut-off 2 μg/mL). Additionally, 8 oncology patients without irAEs were included. In this group, calprotectin levels were similar to those of the healthy controls. In patients with active inflammation, the calprotectin levels in the irAE group were significantly higher (8.43 μg/mL) compared to the RA group (3.94 μg/mL). ROC curve analysis showed that calprotectin had a very good discriminatory capacity to identify inflammatory activity in patients with rheumatic irAEs (AUC of 0.864).

CONCLUSIONS

the results suggest that calprotectin may serve as a marker of inflammatory activity in patients with rheumatic irAEs induced by treatment with ICIs.

High-affinity peptides developed against calprotectin and their application as synthetic ligands in diagnostic assays

Common inflammatory disorders such as ulcerative colitis and Crohn's disease are non-invasively diagnosed or monitored by the biomarker calprotectin. However, current quantitative tests for calprotectin are antibody-based and vary depending on the type of antibody and assay used. Additionally, the binding epitopes of applied antibodies are not characterized by structures and for most antibodies it is unclear if they detect calprotectin dimer, tetramer, or both. Herein, we develop calprotectin ligands based on peptides, that offer advantages such as homogenous chemical composition, heat-stability, site-directed immobilization, and chemical synthesis at high purity and at low cost. By screening a 100-billion peptide phage display library against calprotectin, we identified a high-affinity peptide (K_d = 26 ± 3 nM) that binds to a large surface region (951 Ų) as shown by X-ray structure analysis. The peptide uniquely binds the calprotectin tetramer, which enabled robust and sensitive quantification of a defined species of calprotectin by ELISA and lateral flow assays in patient samples, and thus offers an ideal affinity reagent for next-generation inflammatory disease diagnostic assays.

Circulating Calprotectin (cCLP) in autoimmune diseases

BACKGROUND AND AIM

Calprotectin (CLP) is a heterodimeric complex formed by two S100 proteins (S100A8/A9), which plays a pivotal role in innate immunity. Due to its intrinsic cytotoxic and proinflammatory properties, CLP controls cell differentiation, proliferation and NETosis and has been associated with a wide range of rheumatic diseases. Our review summarizes the widespread interest in circulating CLP (cCLP) as a biomarker of neutrophil-related inflammation, in autoimmune rheumatic disease (ARD) and non-ARD.

METHODS

A thorough literature review was performed using PubMed and EMBASE databases searching for circulating calprotectin and synonyms S100A8/A9, myeloid-related protein 8/14 (MRP8/MRP14), calgranulin A/B and L1 protein in addition to specific ARDs and autoimmune non-rheumatic diseases. We selected only English-language articles and excluded abstracts without the main text.

RESULTS

High cCLP serum levels are associated with worse structural outcomes in rheumatoid arthritis and to a lesser extent, in spondyloarthritis. In addition, cCLP can predict disease relapse in some autoimmune diseases including systemic lupus erythematosus (SLE), anti-neutrophil cytoplasmic antibodies-associated vasculitis (AAV) and some severe manifestations of connective tissue diseases, such as glomerulonephritis in SLE, AAV, juvenile idiopathic arthritis, adult-onset Still's disease and lung fibrosis in systemic sclerosis. Therefore, cCLP levels enable the identification of patients who need an accurate and tight follow-up. The clinical usefulness of cCLP as an inflammatory marker has been suggested for inflammatory/autoimmune non-rheumatic diseases, and especially for the monitoring of the inflammatory bowel diseases patients. Currently, there are only a few studies that evaluated the cCLP efficacy as a clinical biomarker in inflammatory/autoimmune non-rheumatic diseases with controversial results. Future studies are warranted to better clarify the role of cCLP in relation to the disease severity in myasthenia gravis, multiple sclerosis, chronic inflammatory demyelinating polyneuropathy, Graves' orbitopathy, autoimmune bullous diseases and uveitis.

CONCLUSION

Our literature review supports a relevant role of cCLP as potential prognostic biomarker mirroring local or systemic inflammation, especially in chronic inflammatory rheumatic diseases.

Serum Calprotectin and B-cell activating factor are potential biomarkers for Helicobacter pylori infection

Humans always mount a robust immune response to the bacterial infection caused by Helicobacter pylori, which causes various gastrointestinal tract infections. Calprotectin (CALP) and B-Cell Activating Factor (BAFF) are inflammatory biomarkers having a role in the gastrointestinal neutrophilic response to bacterial infection. The study was designed to assess serum CALP and BAFF as inflammatory biomarkers in H. pylori infection and peptic ulcer patients. The current study comprised 112 people, including 62 H. pylori-infected patients (34 men and 28 women) who were clinically diagnosed with H. pylori infection via testing positive for the H. pylori stool antigen test; they were compared to a control group of 50 healthy people (34 men and 16 women) who were age and gender-matched to H. pylori-infected patients. The serum level of CALP and BAFF were assayed using the ELISA technique. The biochemical parameters were statistically compared between patients and controls by unpaired Man-Whitney U t-test and Receiver Operating Characteristic (ROC) curve analysis. There was a significant elevation of serum CALP in H. pylori-infected patients [116.4(120.7), p=0.0132] in comparison to healthy controls [99.50(115.8)]. Similarly, there was a significant elevation of serum BAFF concentration in H. pylori-infected patients [485.7(367.1), p=0.0014] in comparison to healthy controls [444.5(513.0)]. The ROC curve analysis suggests serum CALP and BAFF as reasonable inflammatory biomarkers for H. pylori infection with statistically significant (p=0.0135, p=0.0015) area under the ROC curve of (0.6361, 0.6748), respectively. CALP and BAFF are potent inflammatory biomarkers involved in the development and etiology of H. pylori infection. Serum CALP and BAFF levels could be used as biomarkers for chronic inflammation induced by H. pylori. CALP and BAFF biomarkers can be combined to diagnose and predict the prognosis of H. pylori infection.

Analysis of Systemic Epigenetic Alterations in Inflammatory Bowel Disease: Defining Geographical, Genetic and Immune-Inflammatory influences on the Circulating Methylome

BACKGROUND

Epigenetic alterations may provide valuable insights into gene-environment interactions in the pathogenesis of inflammatory bowel disease [IBD].

METHODS

Genome-wide methylation was measured from peripheral blood using the Illumina 450k platform in a case-control study in an inception cohort (295 controls, 154 Crohn's disease [CD], 161 ulcerative colitis [UC], 28 IBD unclassified [IBD-U)] with covariates of age, sex and cell counts, deconvoluted by the Houseman method. Genotyping was performed using Illumina HumanOmniExpressExome-8 BeadChips and gene expression using the Ion AmpliSeq Human Gene Expression Core Panel. Treatment escalation was characterized by the need for biological agents or surgery after initial disease remission.

RESULTS

A total of 137 differentially methylated positions [DMPs] were identified in IBD, including VMP1/MIR21 [p = 9.11 × 10-15] and RPS6KA2 [6.43 × 10-13], with consistency seen across Scandinavia and the UK. Dysregulated loci demonstrate strong genetic influence, notably VMP1 [p = 1.53 × 10-15]. Age acceleration is seen in IBD [coefficient 0.94, p < 2.2 × 10-16]. Several immuno-active genes demonstrated highly significant correlations between methylation and gene expression in IBD, in particular OSM: IBD r = -0.32, p = 3.64 × 10-7 vs non-IBD r = -0.14, p = 0.77]. Multi-omic integration of the methylome, genome and transcriptome also implicated specific pathways that associate with immune activation, response and regulation at disease inception. At follow-up, a signature of three DMPs [TAP1, TESPA1, RPTOR] were associated with treatment escalation to biological agents or surgery (hazard ratio of 5.19 [CI: 2.14-12.56], logrank p = 9.70 × 10-4).

CONCLUSION

These data demonstrate consistent epigenetic alterations at diagnosis in European patients with IBD, providing insights into the pathogenetic importance and translational potential of epigenetic mapping in complex disease.

Pursuing neutrophils: systematic scoping review on blood-based biomarkers as predictors of treatment outcomes in inflammatory bowel disease

Background

Long-term management of inflammatory bowel diseases (IBD) is challenging and the identification of reliable predictors for treatment outcomes is an unmet need. Neutrophil-related biomarkers have been mainly studied in the feces, but blood analyses have inherent advantages.

Objective

To review the recent learnings on the ability of blood-based neutrophil-expressed biomarkers to predict treatment outcomes in IBD.

Design

Systematic scoping review.

Data sources and methods

We performed a literature search in Pubmed, EMBASE, SCOPUS, Web of Science, ScienceDirect, and Cochrane Central Register of Controlled Trials from inception until May 2022 according to Preferred Reporting Items for Systematic reviews and Meta-Analyses guidelines. All human studies associating blood-based neutrophil-related compounds with the prediction of disease progression, complication onset, or treatment outcomes were included.

Results

From 1032 retrieved entries, 34 studies were selected, 32 published in 2013 or later. In all, 17 biomarkers from granules, cytoplasm, plasmatic membrane, and plasma were explored. In total, 1850 Crohn's disease (CD) and 1122 ulcerative colitis non-duplicated patients were included. The most mentioned biomarkers were nCD64, serum calprotectin (SC), oncostatin M (OSM), neutrophil elastase-generated calprotectin fragment (CPa9-HNE), and triggering receptor expressed on myeloid cells 1 (TREM1). Six biomarkers showed promising results: OSM, SC, eNAMPT, nCD64, TREM1, and CPa9-HNE. Variable positive signals were found for human neutrophil peptide 1-3, LL-37, S100A12, and neutrophil gelatinase-associated lipocalin. No predictive ability was found for the remaining markers. Sharing a neutrophil compartment did not indicate similar behavior.

Conclusion

Advances in the last decade began to unveil the untapped potential of the readily accessible blood neutrophil-expressed biomarkers, especially nCD64, TREM1, and CPa9-HNE. Current evidence suggests that future research should focus on well-defined subpopulations instead of a one-size-fits-all biomarker.

Registration

https://osf.io/kes9a.

Fructose malabsorption in ChREBP-deficient mice disrupts the small intestine immune microenvironment and leads to diarrhea-dominant bowel habit changes

BACKGROUND

The mechanism by which incompletely absorbed fructose causes gastrointestinal symptoms is not fully understood. In this study, we investigated the immunological mechanisms of bowel habit changes associated with fructose malabsorption by examining Chrebp-knockout mice exhibiting defective fructose absorption.

METHODS

Mice were fed a high-fructose diet (HFrD), and stool parameters were monitored. The gene expression in the small intestine was analyzed by RNA sequencing. Intestinal immune responses were assessed. The microbiota composition was determined by 16S rRNA profiling. Antibiotics were used to assess the relevance of microbes for HFrD-induced bowel habit changes.

RESULTS

Chrebp-knockout (KO) mice fed HFrD showed diarrhea. Small-intestine samples from HFrD-fed Chrebp-KO mice revealed differentially expressed genes involved in the immune pathways, including IgA production. The number of IgA-producing cells in the small intestine decreased in HFrD-fed Chrebp-KO mice. These mice showed signs of increased intestinal permeability. Chrebp-KO mice fed a control diet showed intestinal bacterial imbalance, which the HFrD exaggerated. Bacterial reduction improved diarrhea-associated stool parameters and restored the decreased IgA synthesis induced in HFrD-fed Chrebp-KO mice.

CONCLUSIONS

The collective data indicate that gut microbiome imbalance and disrupting homeostatic intestinal immune responses account for the development of gastrointestinal symptoms induced by fructose malabsorption.

Treatment escalation and de-escalation decisions in Crohn's disease: Delphi consensus recommendations from Japan, 2021

BACKGROUND

We aimed to develop criteria for treatment intensification in patients with (1) luminal Crohn's disease (CD), (2) CD with perianal disease and/or fistula, (3) CD with small bowel stenosis, (4) in the postoperative setting, and (5) for discontinuing or reducing the dose of treatment in patients with CD.

METHODS

PubMed and Embase were searched for studies published since 1998 which may be relevant to the five defined topics. Results were assessed for relevant studies, with preference given to data from randomized, controlled studies. For each question, a core panel of 12 gastroenterologists defined the treatment target and developed statements, based on the literature, current guidelines, and relevant additional studies. The evidence supporting each statement was graded using the Oxford Centre for Evidence-Based Medicine: Levels of Evidence (March 2009). A modified Delphi process was used to refine statements and gain agreement from 54 Japanese specialists at in-person and online meetings conducted between October 2020 and April 2021.

RESULTS

Seventeen statements were developed for treatment intensification in luminal CD (targeting endoscopic remission), six statements for treatment intensification in perianal/fistulizing CD (targeting healing of perianal lesions and complete closure of the fistula), six statements for treatment intensification in CD with small bowel stenosis (targeting resolution of obstructive symptoms), seven statements for treatment intensification after surgery (targeting endoscopic remission), and five statements for discontinuing or reducing the dose of treatment in patients with CD.

CONCLUSIONS

These statements provide guidance on how and when to intensify or de-intensify treatment for a broad spectrum of patients with CD.

Is canine calprotectin in serum stabile after storage at low temperature?

BACKGROUND

In human and veterinary medicine calprotectin is most widely used in diagnosing different gastro-intestinal diseases. The aim of this study was to assess the stability of canine calprotectin (cCP) in serum after storage at low temperatures and imprecision of the method.

METHODS

Blood samples were collected from dogs with different clinical diagnoses. Twenty-two dogs were included in this study. Calprotectin concentration was measured 4 hours after serum separation (T0), and after being frozen at - 80 °C for 8 (T1) and 16 weeks (T2). The maximum permissible difference (MPD) was derived from the equation for calculating total error (TE) TE = %Bias + (1.96 x %CV), where bias and coefficient of variation (CV) were defined by the manufacturer. The dogs enrolled in this study were patients admitted during the morning (9-12 a.m.), on the day the first measurement was performed. All sample analysis for determination of stability were done in duplicates. For determination of within-run precision, the two patients' serum samples were analyzed in 20 replicates. Imprecision was assessed by analyzing 20 replicates on one plate on two samples where high and low concentrations were anticipated.

RESULTS

The calculated value of MPD was 32.52%. Median calprotectin concentrations were higher at T1 114.08 μg/L (IQR = 55.05-254.56) and T2 133.6 μg/L (IQR = 100.57-332.98) than at T0 83.60 μg/L (IQR = 50.38-176.07). Relative and absolute bias at T1 (49.3%; 45.98 μg/L) and T2 (109.93%; 94.09 μg /L) have shown that calprotectin concentrations increase after long term storage at - 80 °C.

CONCLUSION

The results of the present study indicate that c-CP was not stable for 16 weeks at low storage temperature (- 80 °C). Considering the observed change in the concentration of c-CP at T1, a storage time of 8 weeks should be safely applied. The method imprecision was not satisfactory, especially in the lower concentration range.

Blood Cell Responses Following Heavy Alcohol Consumption Coincide with Changes in Acute Phase Reactants of Inflammation, Indices of Hemolysis and Immune Responses to Ethanol Metabolites

Aberrations in blood cells are common among heavy alcohol drinkers. In order to shed further light on such responses, we compared blood cell status with markers of hemolysis, mediators of inflammation and immune responses to ethanol metabolites in alcohol-dependent patients at the time of admission for detoxification and after abstinence. Blood cell counts, indices of hemolysis (LDH, haptoglobin, bilirubin), calprotectin (a marker of neutrophil activation), suPAR, CD163, pro- and anti-inflammatory cytokines and autoantibodies against protein adducts with acetaldehyde, the first metabolite of ethanol, were measured from alcohol-dependent patients (73 men, 26 women, mean age 43.8 ± 10.4 years) at baseline and after 8 ± 1 days of abstinence. The assessments also included information on the quantities of alcohol drinking and assays for biomarkers of alcohol consumption (CDT), liver function (AST, ALT, ALP, GGT) and acute phase reactants of inflammation. At baseline, the patients showed elevated values of CDT and biomarkers of liver status, which decreased significantly during abstinence. A significant decrease also occurred in LDH, bilirubin, CD163 and IgA and IgM antibodies against acetaldehyde adducts, whereas a significant increase was noted in blood leukocytes, platelets, MCV and suPAR levels. The changes in blood leukocytes correlated with those in serum calprotectin (p < 0.001), haptoglobin (p < 0.001), IL-6 (p < 0.02) and suPAR (p < 0.02). The changes in MCV correlated with those in LDH (p < 0.02), MCH (p < 0.01), bilirubin (p < 0.001) and anti-adduct IgG (p < 0.01). The data indicates that ethanol-induced changes in blood leukocytes are related with acute phase reactants of inflammation and release of neutrophil calprotectin. The studies also highlight the role of hemolysis and immune responses to ethanol metabolites underlying erythrocyte abnormalities in alcohol abusers.

Protective mechanisms of Zanthoxylum bungeanum essential oil on DSS-induced ulcerative colitis in mice based on a colonic mucosal transcriptomic approach

The ameliorative effects on ulcerative colitis (UC) as well as the related mechanisms of the essential oil derived from the edible herb Zanthoxylum bungeanum Maxim (ZBEO) have been demonstrated herein. Based on GC-MS analysis, 45 volatile compounds in ZBEO were determined for its quality control. In vitro studies showed that after pretreatment with ZBEO, the disordered expression levels of pro-inflammatory cytokines (TNF-α, IL-6, and IL-1β) and an anti-inflammatory cytokine (IL-10) on colon epithelial NCM460 cells induced by lipopolysaccharide (LPS) could be reversed. Additionally, oral administration of ZBEO significantly alleviated colitis in dextran sulfate sodium (DSS)-induced UC mice, including body weight loss, colon length shortening, disease activity index and colonic pathological damage. Furthermore, to uncover the anti-UC mechanisms of ZBEO, analysis of transcriptomes by next-generation sequencing technology was performed to explore the RNA genetic variation on colon tissues. Based on GO analysis and KEGG pathway analysis, a series of genetic pathways involved in the protective role of ZBEO against UC were determined. As a result, ZBEO treatment could decrease the expression of VCAM-1, TLR8, IL-1β and IL-11 mRNA as verified by qRT-PCR, which are involved in these potential genetic pathways. In conclusion, ZBEO administration would be a medicinal or dietary supplementation strategy for ulcerative colitis treatment.

A Specific Calprotectin Neo-epitope [CPa9-HNE] in Serum from Inflammatory Bowel Disease Patients Is Associated with Neutrophil Activity and Endoscopic Severity

BACKGROUND AND AIMS

Endoscopy and the use of faecal calprotectin [faecal CP] are among the least-favoured methods for assessing disease activity by inflammatory bowel disease [IBD] patients; the handling/processing of faecal samples is also impractical. Therefore, we sought to develop a novel neo-epitope serum calprotectin enzyme-linked immunosorbent assay [ELISA], CPa9-HNE, with the aim of quantifying neutrophil activity and neutrophil extracellular trap [NET]-osis and proposing a non-invasive method for monitoring disease activity in IBD patients.

METHODS

In vitro cleavage was performed by mixing calprotectin [S100A9/S100A8] with human neutrophil elastase [HNE], and a novel HNE-derived calprotectin neo-epitope [CPa9-HNE] was identified by mass spectrometry for ELISA development. The CPa9-HNE ELISA was quantified in supernatants from ex vivo activated neutrophils and serum samples from patients with ulcerative colitis [UC, n = 43], Crohn's disease [CD, n = 93], and healthy subjects [HS, n = 23]. For comparison, faecal CP and MRP8/14 biomarkers were also measured.

RESULTS

CPa9-HNE was specific for activated neutrophils ex vivo. Serum CPa9-HNE levels were 4-fold higher in CD [p <0.0001] and UC [p <0.0001] patients than in HS. CPa9-HNE correlated well with the Simple Endoscopic Score [SES]-CD score [r = 0.61, p <0.0001], MES [r = 0.46, p = 0.0141], and the full Mayo score [r = 0.52, p = 0.0013]. CPa9-HNE was able to differentiate between CD and UC patients in endoscopic remission and moderate/severe disease activity (CD: area under the curve [AUC] = 0.82 [p = 0.0003], UC: AUC = 0.87 [p = 0.0004]). The performance of CPa9-HNE was equipotent or slightly better than that of faecal CP.

CONCLUSIONS

Serum CPa9-HNE levels were highly associated with CD and UC patients. CPa9-HNE correlated with the SES-CD score and the full Mayo score, indicating a strong association with disease activity.

Phytogenic feed additives alleviate pathogenic Escherichia coli-induced intestinal damage through improving barrier integrity and inhibiting inflammation in weaned pigs

Background

This study was conducted to investigate the effects of each phytogenic feed additive (PFA; PFA1, bitter citrus extract; PFA2, a microencapsulated blend of thymol and carvacrol; PFA3, a mixture of bitter citrus extract, thymol, and carvacrol; PFA4, a premixture of grape seed, grape marc extract, green tea, and hops; PFA5, fenugreek seed powder) on the growth performance, nutrient digestibility, intestinal morphology, and immune response in weaned pigs infected with Escherichia coli (E. coli).

Results

A total of 63 4-week-old weaned pigs were placed in individual metabolic cages and assigned to seven treatment groups. The seven treatments were as follows: 1) NC; basal diet without E. coli challenge, 2) PC; basal diet with E. coli challenge, 3) T1; PC + 0.04% PFA1, 4) T2; PC + 0.01% PFA2, 5) T3; PC + 0.10% PFA3, 6) T4; PC + 0.04% PFA4, 7) T5; PC + 0.10% PFA5. The experiments lasted in 21 d, including 7 d before and 14 d after the first E. coli challenge. In the E. coli challenge treatments, all pigs were orally inoculated by dividing a total of 10 mL of E. coli F18 for 3 consecutive days. The PFA-added groups significantly increased (P < 0.05) average daily gain and feed efficiency and decreased (P < 0.05) the fecal score at d 0 to 14 post-inoculation (PI). Tumor necrosis factor α was significantly lower (P < 0.05) in the PFA-added groups except for T1 in d 14 PI compared to the PC treatment. The T3 had a higher (P < 0.05) immunoglobulin G and immunoglobulin A concentration compared to the PC treatment at d 7 PI. Also, T3 showed significantly higher (P < 0.05) villus height:crypt depth and claudin 1 expression in ileal mucosa, and significantly down-regulated (P < 0.05) the expression of calprotectin compared to the PC treatment.

Conclusions

Supplementation of PFA in weaned pigs challenged with E. coli alleviated the negative effects of E. coli and improved growth performance. Among them, the mixed additive of bitter citrus extract, thymol, and carvacrol showed the most effective results, improving immune response, intestinal morphology, and expression of tight junctions.

Prostaglandins and calprotectin are genetically and functionally linked to the Inflammatory Bowel Diseases

BACKGROUND

Genome wide association studies (GWAS) have identified and validated more than 200 genomic loci associated with the inflammatory bowel disease (IBD), although for most the causal gene remains unknown. Given the importance of myeloid cells in IBD pathogenesis, the current study aimed to uncover the role of genes within IBD genetic loci that are endogenously expressed in this cell lineage.

METHODS

The open reading frames (ORF) of 42 genes from IBD-associated loci were expressed via lentiviral transfer in the THP-1 model of human monocytes and the impact of each of these on the cell's transcriptome was analyzed using a RNA sequencing-based approach. We used a combination of genetic and pharmacologic approaches to validate our findings in the THP-1 line with further validation in human induced pluripotent stem cell (hiPSC)-derived-monocytes.

RESULTS

This functional genomics screen provided evidence that genes in four IBD GWAS loci (PTGIR, ZBTB40, SLC39A11 and NFKB1) are involved in controlling S100A8 and S100A9 gene expression, which encode the two subunits of calprotectin (CP). We demonstrated that increasing PTGIR expression and/or stimulating PTGIR signaling resulted in increased CP expression in THP-1. This was further validated in hiPSC-derived monocytes. Conversely, knocking-down PTGIR endogenous expression and/or inhibiting PTGIR signaling led to decreased CP expression. These analyses were extended to the known IBD gene PTGER4, whereby its specific agonist also led to increased CP expression. Furthermore, we demonstrated that the PTGIR and PTGER4 mediated control of CP expression was dependent on signaling via adenylate cyclase and STAT3. Finally, we demonstrated that LPS-mediated increases in CP expression could be potentiated by agonists of PTGIR and PTGER4, and diminished by their antagonists.

CONCLUSION

Our results support a causal role for the PTGIR, PTGER4, ZBTB40, SLC39A11 and NFKB1 genes in IBD, with all five genes regulating the expression of CP in myeloid cells, as well as potential roles for the prostacyclin/prostaglandin biogenesis and signaling pathways in IBD susceptibility and pathogenesis.

The value of fecal calprotectin in Clostridioides difficile infection: A systematic review

As a marker of inflammation, calprotectin has potential application value in a variety of inflammatory diseases, such as arthritis and bacterial infections. Clostridioides difficile infection (CDI) is an infectious disease that causes intestinal damage and inflammation. This systematic review aims to determine whether fecal calprotectin has application value in CDI. Nine databases were searched from inception to 6 June 2022, and 17 studies were included. These studies were divided into four groups according to their content. Generally speaking, fecal calprotectin is not an ideal indicator for the diagnosis and prognosis prediction of CDI but may serve as a potential indicator for assessing disease severity and as a readily detectable marker for CDI screening. In addition, patients in need of treatment or with detectable toxins in stool may tend to have higher levels of fecal calprotectin. In summary, fecal calprotectin has some potential application value in CDI. However, further studies are needed to verify these findings and determine the reliability of calprotectin as a biomarker for CDI.

Diagnostic performance of serum calprotectin in discriminating active from inactive ulcerative colitis in an outpatient setting

BACKGROUND

There are limited and conflicting data on the value of serum calprotectin (sCp) in discriminating active from inactive disease activity in ulcerative colitis (UC).

METHODS

Faecal calprotectin (fCp), sCp, serum C-reactive protein (sCRP) and platelets were compared in patients with UC who had clinically active (n=29) and clinically inactive (n=42) disease. sCp was measured with Bühlmann® (BMN sCp) and ImmunodiagnostikTM (IDK sCp) assays.

RESULTS

Median (interquartile range) fCp was higher in active than inactive disease [1004 (466 - 1922) vs 151 (55 - 280) µg/g; p < 0.0001). BMN sCp [4534 (3387 - 6416) vs 4031 (2401 - 5414) ng/mL; p = 0.1825], IDK sCp [4531 (2920 - 6433) vs 3307 (2104 - 4789) ng/mL; p = 0.1065], sCRP [ 4 (2 - 8) vs 2 (1 - 4) mg/L; p = 0.0638) and platelets [269 (233 - 331) vs 280 (227 - 325) x10-9/L; p = 0.8055] were similar in active and inactive disease respectively. The area under the receiver operator characteristics curves with 95% confidence limits were 0.85 (0.76 - 0.94) for fCp, 0.61 (0.47 - 0.74) for BMN sCp, 0.61 (0.48 - 0.75) for IDK sCp, 0.69 (0.56 - 0.81) for sCRP, and 0.52 (0.38 - 0.66) for blood platelets.

CONCLUSIONS

FCp is the optimum biomarker for discriminating between active and inactive UC. The diagnostic performance of sCp, irrespective of assay, and systemic biomarkers was poor; of these sCRP performed best.

Calprotectin in Chronic Inflammatory Demyelinating Polyneuropathy and Variants-A Potential Novel Biomarker of Disease Activity

Background: In chronic inflammatory demyelinating polyneuropathy (CIDP), there is an urgent need for biomarkers to monitor ongoing disease activity. Serum calprotectin (CLP) induces signaling pathways involved in inflammatory processes and has been shown to correlate with markers of disease activity in other autoimmune disorders. Thus, we wanted to study the potential value of CLP in comparison to serum neurofilament light chain (sNfl) to monitor disease activity.

Materials and Methods: Sera from 63 typical and atypical CIDP and 6 MMN patients with varying degrees of disease activity were analyzed in comparison with 40 healthy controls (HC) in a cross-sectional design. Association of CLP and sNfl levels with socio-demographics, disease duration, CIDP disease activity scale (CDAS), and impairment status [medical research council-sum score (MRC-SS), the inflammatory neuropathy cause and treatment disability score (INCAT-DS), grip strength, and maximum walking distance], patient-reported outcome (PRO) parameters [SF-36 questionnaire, Beck's depression index (BDI), and fatigue severity scale (FSS)], as well as treatment regime were investigated using uni- and multivariate analysis.

Results: CLP and sNfl levels were significantly higher in all CIDP patients compared to HC (p = 0.0009). Multivariate analysis adjusted for age and gender revealed that CLP acts as an independent predictor for CIDP and MMN. CLP was significantly associated with active disease course according to CDAS and correlated with MRC-SS, whereas sNfl correlated with parameters of disease impairment. There was no correlation with PRO, except for sNfl and the mental health composite score. Subgroup analysis revealed no differences between typical CIDP and atypical variants.

Conclusions: CLP was elevated in CIDP and variants and was associated with active disease course, whereas sNfl shows further potential as biomarker of axonal degeneration. Thus, CLP might be a suitable additive biomarker for measurement of ongoing inflammation, which is greatly needed to guide better patient care in CIDP.

Preclinical Markers in Inflammatory Bowel Disease. A Nested Case-Control Study

Background

Our objective was to determine if patients who later develop inflammatory bowel disease (IBD) show signs of increased inflammatory activity in plasma measured with high sensitivity C-reactive protein (CRP), calprotectin, and albumin before the clinical onset of IBD.

Methods

We identified 96 subjects who later developed IBD (70 ulcerative colitis [UC] and 26 Crohn's disease [CD]). High sensitivity CRP, calprotectin, and albumin were analyzed in frozen plasma, donated from cases and sex-age matched controls 1-15 years before diagnosis.

Results

We found that subjects who later developed UC had lower albumin levels, and subjects who later developed CD had higher CRP levels than controls. Multivariable conditional logistic regression with albumin, calprotectin, and CRP showed a lower risk for developing IBD and UC with higher albumin levels (odds ratio [OR] 0.79, confidence interval [CI] 0.69-0.90; respective OR 0.77, CI 0.66-0.91). Higher CRP levels were associated with an increased risk of developing CD (OR 1.314, CI 1.060-1.630). When adjusting for body mass index or smoking in the logistic regression model, similar results were found. Plasma calprotectin levels in the preclinical period among patients with IBD did not differ from controls.

Conclusions

In this nested case-control study, subjects who later developed IBD had signs of low-grade systemic inflammation, indicated by significantly higher CRP plasma levels in CD and lower albumin plasma levels in UC, before the onset of clinical disease.

Comparison of serum calprotectin, a marker of neutrophil activation, and other mediators of inflammation in response to alcohol consumption

AIMS

Previous studies have indicated that heavy alcohol intake stimulates inflammation and impairs the body's ability to regulate inflammation. The aim of this study was to compare changes in neutrophil calprotectin and a wide spectrum of other inflammatory mediators in response to heavy alcohol drinking.

METHODS

Serum calprotectin (a marker of neutrophil activation), suPAR, CD163, and pro- (IL-6, IL-8, TNF-α) and anti-inflammatory (IL-10, TGF-β) cytokines were measured from 61 alcohol-dependent subjects (46 men, 15 women, mean age 43.6 ± 11.0 years) at the time of admission for detoxification and after 8 ± 2 days of abstinence. These biomarkers were also measured from age- and sex-matched healthy controls representing abstainers or light drinkers. The clinical assessments included detailed clinical interviews on the amounts and patterns of alcohol consumption and assays for biomarkers of alcohol consumption (GGT, CDT, MCV, GGT-CDT) and liver function (AST, ALT).

RESULTS

The subjects with alcohol use disorder showed significantly higher concentrations of serum calprotectin (p < 0.0005), suPAR (p < 0.01), CD163 (p < 0.01), IL-6 (p < 0.0005), IL-8 (p < 0.0005), TNF-α (p < 0.001), and IL-10 (p < 0.0005) than healthy controls. These inflammatory mediators, except for CD163, remained elevated after the 8 ± 2-day period of supervised abstinence, which resulted in significant decreases in the biomarkers of alcohol consumption and indices of liver status. The AUC (0.855) for serum calprotectin in differentiating between the heavy drinkers and healthy controls was equal or equivalent with those of the conventional biomarkers of alcohol consumption (GGT:0.835 or CDT:0.803).

CONCLUSIONS

The data indicate that neutrophil calprotectin is released in response to heavy alcohol intake in a sensitive manner and may be associated with perpetuation of inflammation in patients with alcohol use disorder. Serum calprotectin may also prove to be a useful biomarker for inflammatory activity in alcohol-consuming patients.

Calprotectin as potential novel biomarker in myasthenia gravis

Myasthenia gravis (MG) is the most common autoimmune disease affecting the neuromuscular junction by specific autoantibodies. The etiology of MG and its heterogeneity in clinical courses are poorly understood, although it was recently shown that gut microbial dysbiosis plays a critical role. Since levels of Calprotectin (CLP) seem to correlate with level of dysbiosis, we hypothesize that CLP may serve as potential disease activity biomarker in MG. Sera from 251 patients with MG and 90 controls were analyzed in an explorative, cross-sectional design. Prospectively, we tested CLP levels in MG patients up to 3 years. Association of CLP levels with socio-demographics, disease activity (quantitative myasthenia gravis (QMG) score, myasthenia gravis-specific Activities of Daily Living scale (MG-ADL)), antibody (Abs) status, history of myasthenic crisis, treatment regime, and history of thymectomy were investigated using univariate analysis. Mean baseline serum levels of CLP were significantly higher in MG patients compared to controls (4.3 μg/ml vs. 2.1 μg/ml; p < 0.0001). Higher levels of CLP were associated with a higher clinical disease severity measured by MGFA classification and QMG score. Nevertheless, the only weak correlation of CLP with clinical outcome parameters needs confirmation in future studies. Currently, there are no validated blood biomarkers for MG. The significantly elevated CLP and mild correlation with parameters of disease activity suggests that CLP holds promise as a biomarker for measurement of individual disease severity.

Association of Serum Neuron-Specific Enolase and C-Reactive Protein With Disease Location and Endoscopic Inflammation Degree in Patients With Crohn's Disease

Objective: The objective of this study was to explore the association between serum markers neuron-specific enolase (NSE) and C-reactive protein (CRP) with intestinal lesion location and degree of inflammation in patients with Crohn's disease (CD). Design: The levels of serum NSE, CRP, and fecal calprotectin (FC) in patients with CD were analyzed retrospectively. The severity of inflammatory lesions in the intestinal wall was accessed using the Simple Endoscopic Score for Crohn's disease (SES-CD). Results: The levels of NSE in patients with CD were higher than those of healthy individuals (14.87 vs. 12.68 ng/ml, P < 0.001). The levels of CRP in patients with CD were higher than those of healthy individuals (12.30 vs. 3.40 mg/l, P < 0.001). The FC levels in patients with CD were higher than those of patients with non-inflammatory bowel disease (1,143.90 vs. 114.21 μg/g, P < 0.05). The levels of NSE in CD with ileal lesions and simultaneous ileal and colon lesions were significantly higher than those in patients with CD with colonic lesions. However, the CRP was higher in patients with colonic lesions than those with ileal lesions. The levels of NSE in patients with severe inflammation were higher than those in patients with moderate inflammation (15.95 vs. 13.89 ng/ml, P < 0.05). Similarly, the NSE levels in patients with CD with severe inflammation were higher than those in patients with CD with mild inflammation (15.95 vs. 13.53 ng/mL, P < 0.05). The levels of CRP in severe inflammation were higher than those in moderate inflammation (29.80 vs. 19.60 mg/l, P < 0.05). In addition, the CRP levels in severe inflammation were higher than those in mild inflammation (29.80 vs. 5.86 mg/l, P < 0.05). ROC curve analysis showed that when NSE was combined with CRP for distinguishing between patients with CD and those without CD, sensitivity increased to 80.41%, specificity increased to 74.66%, and a highest AUC was equal to 0.843. Conclusion: Our study shows that serum NSE and CRP can be used to assess the severity of CD as well as the location of intestinal involvement. Therefore, NSE and CRP could be used as the non-invasive tests in detecting the location and severity of disease in patients with CD in daily routine practice.

Collagenous Gastritis in Children: Incidence, Disease Course, and Associations With Autoimmunity and Inflammatory Markers

Collagenous gastritis (CG), a rare disorder of unknown etiology, has been postulated to have immune-mediated mechanisms. We investigated (i) the incidence and prevalence of CG in a pediatric population; (ii) the clinical, endoscopic, and histologic characteristics of childhood-onset CG; and (iii) the evidence for autoimmunity and/or inflammatory activity in these patients.

Circulating levels of tight junction proteins in multiple sclerosis: Association with inflammation and disease activity before and after disease modifying therapy

BACKGROUND

Tight junction proteins contribute to maintenance of epithelial and endothelial barriers such as the intestinal barrier and the blood brain barrier (BBB). Increased permeability of these barriers has been linked to disease activity in MS and there is currently a lack of easily accessible biomarkers predicting disease activity in MS.

AIM

To investigate whether levels of circulating tight junction proteins occludin and zonula occludens-1 (ZO-1) are associated with biomarkers of inflammation and disease activity; and to determine whether they could serve as clinical biomarkers.

METHODS

We prospectively included 72 newly diagnosed patients with relapsing remitting MS or clinically isolated syndrome with no prior disease modifying therapy (DMT) use and 50 healthy controls (HCs). Patients were followed with blood samples, 3 tesla MRI, and clinical evaluation for 12 months. Occludin, ZO-1, calprotectin and soluble urokinase-type plasminogen activator receptor (suPAR) were measured by ELISA; serum neurofilament light (NfL) and IL-6 by single-molecule array (SIMOA). The mRNA expression of IFNG, IL1R1, IL10, IL1B, ARG1 and TNF was measured by quantitative real time polymerase chain reaction (qPCR) in whole blood.

RESULTS

Plasma occludin levels were higher in MS patients compared with HCs. After 12 months on DMT, occludin levels were reduced by approximately 25% irrespective of 1st or 2nd line DMT (p<0.001). Furthermore, NfL and calprotectin levels were significantly reduced by 31% and 29%, respectively. Occludin and ZO-1 did not correlate with biomarkers of inflammation and did not predict disease activity at baseline or after 12 months.

CONCLUSIONS

Higher levels of occludin suggest an increased permeability of the BBB and/or the intestinal barrier in MS patients. The reduction of occludin after 12 months on DMTs might reflect repair of these barriers upon treatment. However, plasma levels of ZO-1 and occludin could not predict clinical or MRI disease activity as determined by regression and ROC-curve analysis. Our results do not indicate a clear clinically relevant role for circulating tight junction proteins as biomarkers of disease activity in MS and further investigations in larger cohorts are needed to clarify this issue.

Serum and Fecal Markers of Intestinal Inflammation and Intestinal Barrier Permeability Are Elevated in Parkinson's Disease

Parkinson's disease (PD) is characterized by alpha-synuclein misfolding with subsequent intraneuronal amyloid formation and accumulation, low grade neuroinflammatory changes, and selective neurodegeneration. Available evidence suggests that the pathology usually begins in the gut and olfactory mucosa, spreading to the brain via the vagus and olfactory nerves, by a prion-like mechanism. A causal relationship has not been established, but gut dysbiosis is prevalent in PD and may lead to intestinal inflammation and barrier dysfunction. Additionally, epidemiological data indicate a link between inflammatory bowel diseases and PD. Calprotectin and zonulin are markers of intestinal inflammation and barrier permeability, respectively. We evaluated their serum and fecal levels in 22 patients with sporadic PD and 16 unmatched healthy controls. Mean calprotectin was higher in PD, both in serum (14.26 mcg/ml ± 4.50 vs. 5.94 mcg/ml ± 3.80, p = 0.0125) and stool (164.54 mcg/g ± 54.19 vs. 56.19 mcg/g ± 35.88, p = 0.0048). Mean zonulin was also higher in PD serum (26.69 ng/ml ± 3.55 vs. 19.43 ng/ml ± 2.56, p = 0.0046) and stool (100.19 ng/ml ± 28.25 vs. 37.3 ng/ml ± 13.26, p = 0.0012). Calprotectin was above the upper reference limit in 19 PD serums and 6 controls (OR = 10.56, 95% CI = 2.17-51.42, p = 0.0025) and in 20 PD stool samples and 4 controls (OR = 30, 95% CI = 4.75-189.30, p = 0.000045). Increased zonulin was found only in the stool samples of 8 PD patients. Despite the small sample size, our findings are robust, complementing and supporting other recently published results. The relation between serum and fecal calprotectin and zonulin levels and sporadic PD warrants further investigation in larger cohorts.