Biological markers in inflammatory bowel disease: Practical consideration for clinicians

Detailed immune profiling in pediatric Crohn's disease using methylation cytometry

DNA methylation has been extensively utilized to study epigenetic patterns across many diseases as well as to deconvolve blood cell type proportions. This study builds upon previous studies examining methylation patterns in paediatric patients with varying stages of Crohn's disease to extend the immune profiling of these patients using a novel deconvolution approach. Compared with control subjects, we observed significantly decreased levels of CD4 memory and naive, CD8 naive, and natural killer cells and elevated neutrophil levels in Crohn's disease. In addition, Crohn's patients had a significantly elevated neutrophil-to-lymphocyte ratio. Using an epigenome-wide association approach and adjusting for potential confounders, including cell type, we observed 397 differentially methylated CpG (DMC) sites associated with Crohn's disease. The top genetic pathway associated with the DMCs was the regulation of arginine metabolic processes which are involved in the regulation of T cells.

Precision Medicine in Inflammatory Bowel Disease: A Spotlight on Emerging Molecular Biomarkers

Inflammatory bowel diseases (IBD) remain challenging in terms of understanding their causes and in terms of diagnosing, treating, and monitoring patients. Modern diagnosis combines biomarkers, imaging, and endoscopic methods. Common biomarkers like CRP and fecal calprotectin, while invaluable tools, have limitations and are not entirely specific to IBD. The limitations of existing markers and the invasiveness of endoscopic procedures highlight the need to discover and implement new markers. With an ideal biomarker, we could predict the risk of disease development, as well as the possibility of response to a particular therapy, which would be significant in elucidating the pathogenesis of the disease. Recent research in the fields of machine learning, proteomics, epigenetics, and gut microbiota provides further insight into the pathogenesis of the disease and is also revealing new biomarkers. New markers, such as BAFF, PGE-MUM, oncostatin M, microRNA panels, αvβ6 antibody, and S100A12 from stool, are increasingly being identified, with αvβ6 antibody and oncostatin M being potentially close to being presented into clinical practice. However, the specificity of certain markers still remains problematic. Furthermore, the use of expensive and less accessible technology for detecting new markers, such as microRNAs, represents a limitation for widespread use in clinical practice. Nevertheless, the need for non-invasive, comprehensive markers is becoming increasingly important regarding the complexity of treatment and overall management of 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.

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.

Surface design of nanocarriers: Key to more efficient oral drug delivery systems

As nanocarriers (NCs) can improve the solubility of drugs, prevent their degradation by gastrointestinal (GI) enzymes and promote their transport across the mucus gel layer and absorption membrane, the oral bioavailability of these drugs can be substantially enhanced. All these properties of NCs including self-emulsifying drug delivery systems (SEDDS), solid lipid nanoparticles (SLNs), nanostructured lipid carriers (NLCs), liposomes, polymeric nanoparticles, inorganic nanoparticles and polymeric micelles depend mainly on their surface chemistry. In particular, interaction with food, digestive enzymes, bile salts and electrolytes, diffusion behaviour across the mucus gel layer and fate on the absorption membrane are determined by their surface. Bioinert surfaces limiting interactions with gastrointestinal fluid and content as well as with mucus, adhesive surfaces providing an intimate contact with the GI mucosa and absorption enhancing surfaces can be designed. Furthermore, charge converting surfaces shifting their zeta potential from negative to positive directly at the absorption membrane and surfaces providing a targeted drug release are advantageous. In addition to these passive surfaces, even active surfaces cleaving mucus glycoproteins on their way through the mucus gel layer can be created. Within this review, we provide an overview on these different surfaces and discuss their impact on the performance of NCs in the GI tract.

Evaluation of faecal lactoferrin as a morbidity biomarker in Schistosoma mansoni infection

OBJECTIVE

Lactoferrin is an 80 KDa iron-binding glycoprotein that plays a significant role in the innate immune system and is considered to be an important microbicide molecule. This study aimed to assess the concentration of lactoferrin in Schistosoma mansoni-infected cases before and after praziquantel treatment.

METHODS

A cross-sectional study was carried out on 250 individuals aged from 5 to 30 years. Stool samples were examined for the presence of parasitic infections using Kato-Katz and formalin ethyl acetate techniques. All S. mansoni-positive cases were treated with praziquantel and stool samples were recollected 21 days later. Faecal lactoferrin level was determined before and after treatment.

RESULTS

The prevalence of S. mansoni infection was 14.4%. Among 36 participants infected with S. mansoni, the cure rate was 91.7%. A statistically significant difference in the mean lactoferrin level before and after treatment was detected (1648.95 pg/ml ± 656.5 vs. 1162.8 pg/ml ± 356.8). This difference was statistically significant in the middle and older age groups, in males and in the absence of coinfection with other parasites.

CONCLUSION

Lactoferrin could be a promising biomarker associated with S. mansoni infection, however, it could not be used to assess the severity of infection.

Peripheral blood mononuclear cell microRNAs are novel biomarkers for diagnosing and monitoring Crohn's disease

Crohn's disease is a recurrent, progressive, immune-mediated inflammatory disease and merely manifests non-specific symptoms at early stage. In this study, we isolated peripheral blood mononuclear cells (PBMCs) to determine whether PBMC miRNAs are reliable biomarkers for Crohn's disease diagnosing and monitoring. 5 Crohn's disease patients and 5 healthy controls were recruited to find differentially expressed miRNAs by next generation sequencing. Candidate PBMC miRNAs were further validated by qRT-PCR in another cohort consisting of 86 Crohn's disease patients and 39 healthy controls. We found PBMC miR-582-5p could diagnose Crohn's disease with the area under receiver operating characteristic curve (AUROC) of 0.701(95%CI 0.606-0.796, p < .001). While PBMC miR-96-5p was significantly higher in active Crohn's disease and correlated with both clinical (ρ = 0.376, p < .001) and endoscopic activity (ρ = 0.512, p = .015). Furthermore, PBMC miR-96-5p had a better performance in recognizing active Crohn's disease with AUROC of 0.727 (95%CI 0.609-0.844, p = .001) than C-reactive protein (CRP), erythrocyte sedimentation rate (ESR) and fecal calprotectin. In conclusion, PBMC miR-582-5p may be further utilized as a diagnostic biomarker, while miR-96-5p may be a novel and valuable biomarker in monitoring disease activity.

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.

Tools for the Diagnosis and Management of Crohn's Disease

Numerous tools have emerged over recent decades to aid in the increasingly complex management of patients with Crohn's disease (CD) beyond endoscopy, including video capsule endoscopy, magnetic resonance enterography, computed tomography enterography, a variety of biomarkers, and even wearable biosensors and smartphone applications. These tools have allowed for a more sophisticated and less invasive complementary approach to the evaluation of disease activity and treatment response in patients with CD. This article details the characteristics, practical application, and limitations of these various modalities and discusses how updated guidelines are now incorporating many of them into a treat-to-target strategy.

Gut Microbiota Is a Potential Biomarker in Inflammatory Bowel Disease

Inflammatory bowel disease (IBD), which includes ulcerative colitis (UC) and Crohn's disease (CD), is characterized by relapse and remission alternately. It remains a great challenge to diagnose and assess disease activity during IBD due to the lack of specific markers. While traditional biomarkers from plasma and stool, such as C-reactive protein (CRP), fecal calprotectin (FC), and S100A12, can be used to measure inflammation, they are not specific to IBD and difficult to determine an effective cut-off value. There is consensus that gut microbiota is crucial for intestinal dysbiosis is closely associated with IBD etiopathology and pathogenesis. Multiple studies have documented differences in the composition of gut microbiota between patients with IBD and healthy individuals, particularly regarding microbial diversity and relative abundance of specific bacteria. Patients with IBD have higher levels of Proteobacteria and lower amounts of Bacteroides, Eubacterium, and Faecalibacterium than healthy individuals. This review summarizes the pros and cons of using traditional and microbiota biomarkers to assess disease severity and treatment outcomes and addresses the possibility of using microbiota-focused interventions during IBD treatment. Understanding the role of microbial biomarkers in the assessment of disease activity and treatment outcomes has the potential to change clinical practice and lead to the development of more personalized therapies.

Faecal proteomics in the identification of biomarkers to differentiate canine chronic enteropathies

Canine chronic enteropathy (CCE) is a collective term used to describe a group of idiopathic enteropathies of dogs that result in a variety of clinical manifestations of intestinal dysfunction. Clinical stratification into food-responsive enteropathy (FRE) or non-food responsive chronic inflammatory enteropathy (CIE), is made retrospectively based on response to treatments. Faecal extracts from those with a FRE (n = 5) and those with non-food responsive chronic inflammatory enteropathies (CIE) (n = 6) were compared to a healthy control group (n = 14) by applying TMT-based quantitative proteomic approach. Many of the proteins with significant differential abundance between groups were pancreatic or intestinal enzymes with pancreatitis-associated protein (identified as REG3α) and pancreatic M14 metallocarboxypeptidase proteins carboxypeptidase A1 and B identified as being of significantly increased abundance in the CCE group. The reactome analysis revealed the recycling of bile acids and salts and their metabolism to be present in the FRE group, suggesting a possible dysbiotic aetiology. Several acute phase proteins were significantly more abundant in the CCE group with the significant increase in haptoglobin in the CIE group especially notable. Further research of these proteins is needed to fully assess their clinical utility as faecal biomarkers for differentiating CCE cases. SIGNIFICANCE: The identification and characterisation of biomarkers that differentiate FRE from other forms of CIE would prove invaluable in streamlining clinical decision-making and would avoid costly and invasive investigations and delays in implementing effective treatment. Many of the proteins described here, as canine faecal proteins for the first time, have been highlighted in previous human and murine inflammatory bowl disease (IBD) studies initiating a new chapter in canine faecal biomarker research, where early and non-invasive biomarkers for early clinical stratification of CCE cases are needed. Pancreatitis-associated protein, pancreatic M14 metallocarboxypeptidase along with carboxypeptidase A1 and B are identified as being of significantly increased abundance in the CCE groups. Several acute phase proteins, were significantly more abundant in the CCE group notably haptoglobin in dogs with inflammatory enteropathy. The recognition of altered bile acid metabolism in the reactome analysis in the FRE group is significant in CCE which is a complex condition incorporating of immunological, dysbiotic and faecal bile acid dysmetabolism. Both proteomics and immunoassays will enable the characterisation of faecal APPs as well as other inflammatory and immune mediators, and the utilisation of assays, validated for use in analysis of faeces of veterinary species will enable clinical utilisation of faecal matrix to be fully realised.

Optimal Range of Fecal Calprotectin for Predicting Mucosal Healing in Patients with Inflammatory Bowel Disease: A Systematic Review and Meta-Analysis

Objective

Fecal calprotectin (FC) is a promising marker for assessment of inflammatory bowel disease (IBD) activity. However, the utility of FC for predicting mucosal healing (MH) of IBD patients has yet to be clearly demonstrated. The objective of our study was to perform a meta-analysis evaluating the diagnostic accuracy of FC in predicting MH of IBD patients.

Methods

We systematically searched the databases for studies from inception to April 2020 that evaluated MH in IBD. The methodological quality of each study was assessed according to the Quality Assessment of Diagnostic Accuracy Studies checklist. The extracted data were pooled using a summary receiver operating characteristic curve model. Random-effects model was used to summarize the diagnostic odds ratio, sensitivity, specificity, positive likelihood ratio, and negative likelihood ratio.

Results

Sixteen studies comprising 1,682 ulcerative colitis (UC) patients and 4 studies comprising 221 Crohn's disease (CD) patients were included. The best performance of FC for predicting MH in UC was at cut-off range of 60-75 μg/g with area under the curve (AUC) of 0.88 and pooled sensitivity and specificity of 0.87 and 0.79, respectively. The pooled sensitivity and specificity values of cutoff range 180-250 μg/g for predicting MH in CD were 0.67 and 0.76, respectively. The AUC of 0.79 also revealed improved discrimination for identifying MH in CD with FC concentration.

Conclusion

Our meta-analysis has found that FC is a simple, reliable noninvasive marker for predicting MH in IBD patients. FC cutoff range 60-75 μg/g appears to have the best overall accuracy in UC patients.

pH-Responsive Alginate-Based Microparticles for Colon-Targeted Delivery of Pure Cyclosporine A Crystals to Treat Ulcerative Colitis

Cyclosporine A (CsA) is a potent immunosuppressant for treating ulcerative colitis (UC). However, owing to severe systemic side effects, CsA application in UC therapy remains limited. Herein, a colon-targeted drug delivery system consisting of CsA crystals (CsAc)-loaded, Eudragit S 100 (ES)-coated alginate microparticles (CsAc-EAMPs) was established to minimize systemic side effects and enhance the therapeutic efficacy of CsA. Homogeneously-sized CsAs (3.1 ± 0.9 μm) were prepared by anti-solvent precipitation, followed by the fabrication of 47.1 ± 6.5 μm-sized CsAc-EAMPs via ionic gelation and ES coating. CsAc-EAMPs exhibited a high drug loading capacity (48 ± 5%) and a CsA encapsulation efficacy of 77 ± 9%. The in vitro drug release study revealed that CsA release from CsAc-EAMPs was suppressed under conditions simulating the stomach and small intestine, resulting in minimized systemic absorption and side effects. Following exposure to the simulated colon conditions, along with ES dissolution and disintegration of alginate microparticles, CsA was released from CsAc-EAMPs, exhibiting a sustained-release profile for up to 24 h after administration. Given the effective colonic delivery of CsA molecules, CsAc-EAMPs conferred enhanced anti-inflammatory activity in mouse model of dextran sulfate sodium (DSS)-induced colitis. These findings suggest that CsAc-EAMPs is a promising drug delivery system for treating UC.

Effective immune-inflammation index for ulcerative colitis and activity assessments

BACKGROUND

The inverse association between systemic immune-inflammation index (SII) and overall survival in tumors has been studied.

AIM

To evaluate the hematological indexes for assessing the activity of ulcerative colitis (UC).

METHODS

In this case-control study, 172 UC patients and healthy participants were included. Comparisons were made among groups of white blood cells, hemoglobin, platelets, neutrophils, lymphocytes, monocytes, SII, neutrophil-to-lymphocyte ratio (NLR), and platelet-to-lymphocyte ratio (PLR). The relationship with hematological inflammation was verified by Spearman correlation analyses. The efficiency of SII, NLR, and PLR for distinguishing between UC and severe disease status was assessed by the receiver operator curve and logistic regression analyses.

RESULTS

The values of SII, NLR, and PLR were higher in UC patients than in controls (P < 0.001) and were positively correlated with the Mayo endoscopic score, extent, Degree of Ulcerative Colitis Burden of Luminal Inflammation (DUBLIN) score, and Ulcerative Colitis Endoscopic Index of Severity (UCEIS). The cut-off NLR value of 562.22 predicted UC with a sensitivity of 79.65% and a specificity of 76.16%. Logistic regression analysis revealed that patients with SII and NLR levels above the median had a significantly higher risk of UC (P < 0.05). Risk factors independently associated with DUBLIN ≥ 3 included SII ≥ 1776.80 [odds ratio (OR) = 11.53, P = 0.027] and NLR value of 2.67-4.23 (OR = 2.96, P = 0.047) on multivariate analysis. Compared with the first quartile, SII ≥ 1776.80 was an independent predictor of UCEIS ≥ 5 (OR = 18.46, P = 0.012).

CONCLUSION

SII has a certain value in confirming UC and identifying its activity.

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.

Liposomal N-acylethanolamine-hydrolyzing acid amidase (NAAA) inhibitor F96 as a new therapy for colitis

Despite numerous advances in the pathological mechanism of inflammatory bowel disease (IBDs), the ideal therapy is still missing. N-Acylethanolamine-hydrolyzing acid amidase (NAAA), a cysteine hydrolase that deactivates fatty acid ethanolamides, has been recognized as a new therapeutic target for IBDs. Herein, we proposed liposomal F96, a selective and potent NAAA inhibitor, as a new therapy for IBDs. F96, with an IC₅₀ of 270 nM for NAAA, was encapsulated into anionic liposome and the anti-inflammatory activity was evaluated in dextran sulfate sodium (DSS) induced colitis mice. The anionic liposomes showed significantly higher accumulation in the colon compared with the small intestine and cecum at 6 and 10 h after administration in DSS induced colitis mice. DSS induction significantly increased myeloperoxidase (MPO) activities and shortened the colon length, while free F96 significantly lowered tissue MPO activity and restored the colon length. Anionic liposome encapsulation significantly enhanced the therapeutic efficacy of F96, as liposomal F96 resulted in lower MPO activity and better colon length restoration effects compared with those treated with free F96. This study offers a new treatment option for colitis, which may pave the way for new therapies for other IBDs.

Liposomal NAAA inhibitor F96 exhibits potent therapeutic activities against colitis.

Fecal Lactoferrin for Assessment of Inflammatory Bowel Disease Activity: A Systematic Review and Meta-Analysis

OBJECTIVE

Persistent disease activity is associated with a poor prognosis in inflammatory bowel disease (IBD) patients. Therefore, monitoring of IBD activity can avoid the poor prognosis. Serum biomarkers reflect a summation of systemic host responses rather than being specific for intestinal inflammation. And endoscopic monitoring is invasive, costly, and time consuming. The objective of our study was to perform a meta-analysis evaluating the diagnostic accuracy of fecal lactoferrin (FL) in assessing IBD activity.

METHODS

We systematically searched the databases from inception to May 2018 that evaluated IBD activity. The methodological quality of each study was assessed according to the Quality Assessment of Diagnostic Accuracy Studies checklist. The extracted data were pooled using a summary receiver operating characteristic curve model. Random-effects model was used to summarize the diagnostic odds ratio, sensitivity, specificity, positive likelihood ratio, and negative likelihood ratio.

RESULTS

Ten studies comprising 773 IBD patients were included in the meta-analysis. The pooled sensitivity and specificity values for assessing ulcerative colitis (UC) activity were 0.81 [95% confidence interval (CI), 0.64-0.92] and 0.82 (95% CI, 0.61-0.93), respectively. And the pooled sensitivity and specificity values for assessing Crohn's disease (CD) activity were 0.82 (95% CI, 0.73-0.88) and 0.71 (95% CI, 0.63-0.78), respectively. The diagnostic performance of the FL assay in the UC patients appeared to be superior to that in the CD patients.

CONCLUSION

Our meta-analysis has found that FL is an inexpensive, simple, stable, and useful screening marker with high sensitivity and modest specificity for assessing IBD activity, appearing to have greater ability to evaluate UC rather than CD.

Oral delivery of oleuropein-loaded lipid nanocarriers alleviates inflammation and oxidative stress in acute colitis

Inflammation and oxidative stress pathways have emerged as novel targets in the management of inflammatory bowel diseases (IBD). Targeting the drug to the inflamed colon remains a challenge. Nanostructured lipid carriers (NLCs) have been reported to accumulate in inflamed colonic mucosa. The antioxidant/antiinflamatory polyphenol oleuropein (OLE) was loaded in NLCs (NLC-OLE). NLC-OLE showed to be more effective in decreasing the TNF-α secretion and intracellular reactive oxygen species (ROS) by activated macrophages (J774) compared to the conventional form of OLE. OLE efficacy was preserved within NLC-OLE ameliorating inflammation in a murine model of acute colitis: reduced levels of TNF-α and IL-6, decreased neutrophil infiltration and improved histopathology of the colon were reported. In addition, NLC-OLE enhanced the ROS scavenging activity of OLE in the colon after oral administration. These data suggest that the proposed NLC-OLE could be a promising drug delivery system for OLE in IBD treatment.

The effect of a mindfulness-based therapy on different biomarkers among patients with inflammatory bowel disease: a randomised controlled trial

Mindfulness-based interventions have shown some efficacy in decreasing stress levels and improving quality of life. However, so far, only a few studies have studied this type of intervention among patients with inflammatory bowel disease and none of them have studied their effects on inflammatory biomarkers. This current study was a two-armed, single-centre, randomised (2:1 ratio) controlled trial used to evaluate the effects of a mindfulness-based intervention (n = 37) compared to standard medical therapy (n = 20) in patients with Crohn’s disease or ulcerative colitis. The mindfulness intervention blended four internet-based therapy modules with four face-to-face support sessions. The outcomes we assessed were faecal calprotectin (primary outcome), C-reactive protein, and cortisol levels measured in hair samples at several timepoints. The between-group analysis highlighted significant decreases in faecal calprotectin and in C-reactive protein levels in the mindfulness-based intervention group compared to the standard medical therapy group at the six-month follow-up (faecal calprotectin: −367, [95% CI: −705, −29], P = 0.03; C-reactive protein: −2.82, [95% CI: −5.70, 0.08], P = 0.05), with moderate to large effect sizes (faecal calprotectin: ηp² = 0.085; C-reactive protein: ηp² = 0.066). We concluded that mindfulness-based therapy administered as part of standard clinical practice effectively improves inflammatory biomarkers in patients diagnosed with inflammatory bowel disease.

Chitosan-modified lipid nanodrug delivery system for the targeted and responsive treatment of ulcerative colitis

Targeted and sensitive drug release at the colitis site is critical for the effective therapy of ulcerative colitis and reduction of side effects from the drug. Herein, we used 3,3'-dithiodipropionic acid (DTPA) to covalently link quercetin (Qu) and glyceryl caprylate-caprate (Gcc) via ester bonds to prepare Qu-SS-Gcc lipid nanoparticles (Qu-SS-Gcc LNPs). Dexamethasone (Dex) was used as a model drug, and chitosan (CSO) was modified on the surface of Qu-SS-Gcc LNPs to obtain CSO-modified Dex-loaded Qu-SS-Gcc LNPs (CSO/Dex/LNPs). The encapsulation efficiency and drug loading of CSO/Dex/LNPs were 93.1 % and 8.1 %, respectively. The in vitro release results showed that CSO/Dex/LNPs had esterase-responsive characteristics and could release the drug rapidly in esterase-containing artificial intestinal fluid. A human colorectal adenocarcinoma cell (Caco-2) monolayer was used as the intestinal cell barrier model. Transmembrane resistance measurements and permeation experiments showed that CSO/Dex/LNPs had a protective effect on the lipopolysaccharide (LPS)-stimulated Caco-2 cell monolayer and increased the expression of E-cadherin in LPS-stimulated Caco-2 cells. Moreover, CSO/Dex/LNPs could significantly reduce the expression of the inflammatory factors TNF-α, IL-6 and NO in LPS-stimulated RAW 264.7 cells. The ulcerative colitis mouse model was constructed by using C57BL/6 mice. The in vivo distribution results showed that CSO/Dex/LNPs had colon-targeting effects and strong retention ability in the colons of mice with colitis. The results also showed that CSO/Dex/LNPs had better anti-inflammatory effects than free Dex, which could reduce colonic atrophy, reduce histomorphological changes and increase the expression of E-cadherin in the colon. Furthermore, the expression levels of TNF-α, IL-6 and NO in the CSO/Dex/LNP-treated group were 37.4 %, 35.5 % and 33.2 % of those in mice with colitis, respectively.

Up-regulation of syndecan-2 in proximal colon correlates with acute inflammation

We previously reported that syndecan-2 expression is increased on the colonic epithelium during chronic inflammation. Here, we report that syndecan-2 exhibits a different pattern of site-specific colonic expression during acute inflammation. Syndecan-2 expression was up-regulated predominantly in the proximal colon of dextran sulfate sodium-induced colitis mice. The colitis-associated up-regulation of syndecan-2 was barely detected in Rag-1^-/- (recombination activating gene 1 knockout) mice under colitis-inducing conditions. Increased syndecan-2 expression correlated with increased levels of infiltrated CD4⁺ IL-17A⁺ T cells in the proximal colon. Serum levels of IL-17A were increased during the acute inflammatory response in normal mice but not Rag-1^-/- mice. IL-17A directly induced IL-17 receptor (IL-17RA) and syndecan-2 expression in ex vivo-cultured proximal colon tissues and adenoma cell lines from proximal colon. IL-17RA knockdown reduced the IL-17A-mediated syndecan-2 expression in SNU1235 cells. No elevation of syndecan-2 or IL-17RA was observed in colonic tissues from IL-17A^-/- mice during colitis induction. Finally, increased expression of syndecan-2 and IL-17RA was observed in the proximal colons of cecal ligation and puncture-induced sepsis mice and infectious pan colitis patients. Together, these data suggest that acute inflammation induces syndecan-2 expression predominantly in the proximal colon via IL-17A-IL-17RA signaling during the early stage of the inflammatory response and that proximal colonic syndecan-2 might be a biomarker for acute inflammation.-Hong, H., Song, H.-K., Hwang, E. S., Lee, A. R., Han, D. S., Kim, S.-E., Oh, E.-S. Up-regulation of syndecan-2 in proximal colon correlates with acute inflammation.

Differential diagnosis of Crohn's disease using antibodies to glycoprotein 2 and Saccharomyces cerevisiae

BACKGROUND/AIMS

Glycoprotein 2 (GP2), the major autoantigen of Crohn's disease (CD)-specific pancreatic autoantibodies, is reportedly correlated with several characteristics of CD. We investigated this serological marker in Turkish patients with CD and assessed its utility in combination with anti-Saccharomyces cerevisiae antibodies (ASCAs) for differential diagnosis of CD.

MATERIALS AND METHODS

A total of 60 patients with CD, 62 patients with ulcerative colitis (UC), and 46 healthy controls with a definite diagnosis who were similar in age and sex were enrolled in the study conducted from November 2011 to October 2012. ASCA and anti-GP2 levels were measured using commercially available kits.

RESULTS

Anti-GP2 IgA and IgG levels were higher in patients with CD (25%) than in those with UC (5%) and controls (2%). The seroprevalence of anti-GP2 IgA was markedly higher than that of IgG in patients with CD in contrast to previous studies. The specificity and positive predictive value of seropositivity for both ASCA and anti-GP2 were 100%. ASCA IgA seropositivity was correlated with a complicated disease course and a history of surgery. There was no correlation between anti-GP2 seropositivity and disease location, disease behavior, or a history of surgery.

CONCLUSION

The combination of ASCA and anti-GP2 may enable differentiation of CD from UC. As ASCA seropositivity is associated with a more complicated disease course, patients seropositive for ASCA at the initial diagnosis should undergo more intense therapy.

Colon-targeted dexamethasone microcrystals with pH-sensitive chitosan/alginate/Eudragit S multilayers for the treatment of inflammatory bowel disease

Oral colon-targeted drug delivery has gained popularity as an effective strategy for treatment of inflammatory bowel disease (IBD). In this study, we prepared colon-targeted dexamethasone microcrystals (DXMCs) coated with multilayers of chitosan oligosaccharide (CH), alginate (AG), and finally Eudragit S 100 (ES) (ES₁AG₄CH₅-DXMCs) using a layer-by-layer (LBL) coating technique. Particle size, surface charge, in vitro drug release, and in vivo anti-inflammatory activity of ES₁AG₄CH₅-DXMCs were evaluated. ES₁AG₄CH₅-DXMCs had an average particle size of 2.34 ± 0.19 μm and a negative surface charge of - 48 ± 9 mV. ES₁AG₄CH₅-DXMCs demonstrated pH-dependent dexamethasone release, avoiding initial burst drug release in acidic pH conditions of the stomach and small intestine, and providing subsequent sustained drug release in the colonic pH. Importantly, ES₁AG₄CH₅-DXMCs exhibited a significant therapeutic activity in a mouse model of colitis compared to other DXMCs. Overall, the LBL-coated DXMCs presented here could be a promising colon-targeted therapy for IBD.

Role of Positron Emission Tomography in Assessing Disease Activity in Ulcerative Colitis: Comparison with Biomarkers

BACKGROUND

Disease activity in ulcerative colitis (UC) is best assessed clinically by Mayo score. 18-Fluorodeoxyglucose positron emission tomography-computerized tomography (FDG PET-CT) is a noninvasive imaging technique to assess extent, disease activity and response to treatment of UC, especially in high risk population or patients unwilling for endoscopy.

AIMS

We conducted a prospective observational study with the aim of assessing and correlating UC disease activity by clinical criteria, endoscopy, histology, serum and fecal biomarkers, and FDG PET-CT.

METHODS

Sixty eligible patients of UC were enrolled into three groups (26 remission, 24 moderate and 10 severe activity) as per Mayo score and FDG PET-CT was performed within 72 h of colonoscopy. ESR, CRP, and fecal calprotectin (FC) levels were determined for all patients.

RESULTS

Of 60 enrolled patients, 10% patients had proctitis, 43.3% left-sided colitis, and 46.7% extensive colitis. ESR, CRP, FC levels, and rectal PET activity were significantly higher in groups with moderate and severe disease activity. Rectal PET activity showed a significant correlation with the Mayo score (k = 0.465, p < 0.001), endoscopic subscore (k = 0.526, p < 0.001), histological score (k = 0.496, p < 0.001), and FC (k = 0.279, p = 0.031). Extent evaluation by FDG PET-CT and colonoscopy showed a significant correlation (k = 0.582, p < 0.001). Besides, FDG PET-CT identified sacroiliitis in one patient and adenocarcinoma in one patient.

CONCLUSION

FDG PET-CT is a reliable noninvasive tool for detection of disease activity, extent in UC with good correlation with Mayo score, histology and fecal biomarkers and accurate predictor of disease remission.

Mucosal-luminal interface proteomics reveals biomarkers of pediatric inflammatory bowel disease-associated colitis

OBJECTIVE

Improved biomarkers are an unmet clinical need for suspected inflammatory bowel disease (IBD). Need is greatest for children, since current biomarkers suffers from low specificity, particularly in this population; thus, invasive testing methods, with the accompanying risk of complications, are necessary. Additionally, current biomarkers do not delineate disease extent assessment for ulcerative colitis (UC), a factor involved in therapeutic decisions.

METHODS

Intestinal mucosal-luminal interface (MLI) aspirates from the ascending colon (AC) and descending colon (DC) were collected during diagnostic colonoscopy from treatment-naïve children. The MLI proteomes of 18 non-IBD and 42 IBD patients were analyzed by liquid chromatography mass spectrometry. Analyses of proteomic data generated protein panels distinguishing IBD from non-IBD and pancolitis from non-pancolitis (UC disease extent). Select protein biomarkers were evaluated in stool samples by enzyme-linked immunosorbent assay (n = 24).

RESULTS

A panel of four proteins discriminated active IBD from non-IBD (discovery cohort) with a sensitivity of 0.954 (95% confidence interval (CI): 0.772-0.999) and >0.999 (95% CI: 0.824-1.00) for the AC and DC, respectively, and a specificity of >0.999 (AC, 95% CI: 0.815-1.00; DC, 95% CI:0.692-1.00) for both the AC and DC. A separate panel of four proteins distinguished pancolitis from non-pancolitis in UC patients with sensitivity >0.999 (95% CI: 0.590-1.00) and specificity >0.999 (95% CI: 0.715-1.00). Catalase (p < 0.0001) and LTA4H (p = 0.0002) were elevated in IBD stool samples compared to non-IBD stool samples.

CONCLUSION

This study identified panels of proteins that have significantly different expression levels and contribute to accurate IBD diagnosis and disease extent characterization in children with UC. Biomarkers identified from the MLI demonstrate transferable results in stool samples.

Fecal immunochemical test for predicting mucosal healing in ulcerative colitis patients: A systematic review and meta-analysis

BACKGROUND AND AIM

Fecal immunochemical test (FIT) is a promising marker for assessment of inflammatory bowel disease activity. However, the utility of FIT for predicting mucosal healing (MH) of ulcerative colitis (UC) patients has yet to be clearly demonstrated. The objective of our study was to perform a diagnostic test accuracy test meta-analysis evaluating the diagnostic accuracy of FIT in predicting MH of UC patients.

METHODS

We systematically searched the databases from inception to November 2017 that evaluated MH in UC. The methodological quality of each study was assessed according to the Quality Assessment of Diagnostic Accuracy Studies checklist. The extracted data were pooled using a summary receiver operating characteristic curve model. Random-effects model was used to summarize the diagnostic odds ratio, sensitivity, specificity, positive likelihood ratio, and negative likelihood ratio.

RESULTS

Six studies comprising 625 UC patients were included in the meta-analysis. The pooled sensitivity and specificity values for predicting MH in UC were 0.77 (95% confidence interval [CI], 0.72-0.81) and 0.81 (95% CI, 0.76-0.85), respectively. The FIT level had a high rule-in value (positive likelihood ratio, 3.79; 95% CI, 2.85-5.03) and a moderate rule-out value (negative likelihood ratio, 0.26; 95% CI, 0.16-0.43) for predicting MH in UC. The results of the receiver operating characteristic curve analysis (area under the curve, 0.88; standard error of the mean, 0.02) and diagnostic odds ratio (18.08; 95% CI, 9.57-34.13) also revealed improved discrimination for identifying MH in UC with FIT concentration.

CONCLUSION

Our meta-analysis has found that FIT is a simple, reliable non-invasive marker for predicting MH in UC patients.

Colon-targeted delivery of cyclosporine A using dual-functional Eudragit® FS30D/PLGA nanoparticles ameliorates murine experimental colitis

Background

Colon-targeted oral nanoparticles (NPs) have emerged as an ideal, safe, and effective therapy for ulcerative colitis (UC) owing to their ability to selectively accumulate in inflamed colonic mucosa. Cyclosporine A (CSA), an immunosuppressive agent, has long been used as rescue therapy in severe steroid-refractory UC. In this study, we developed CSA-loaded dual-functional polymeric NPs composed of Eudragit^® FS30D as a pH-sensitive polymer for targeted delivery to the inflamed colon, and poly(lactic-co-glycolic acid) (PLGA) as a sustained-release polymer.

Methods

CSA-loaded Eudragit FS30D nanoparticles (ENPs), PLGA nanoparticles (PNPs), and Eudragit FS30D/PLGA nanoparticles (E/PNPs) were prepared using the oil-in-water emulsion method. Scanning electron microscope images and zeta size data showed successful preparation of CSA-loaded NPs.

Results

PNPs exhibited a burst drug release of >60% at pH 1.2 (stomach pH) in 0.5 h, which can lead to unwanted systemic absorption and side effects. ENPs effectively inhibited the burst drug release at pH 1.2 and 6.8 (proximal small intestine pH); however, nearly 100% of the CSA in ENPs was released rapidly at pH 7.4 (ileum–colon pH) owing to complete NP dissolution. In contrast to single-functional PNPs and ENPs, the dual-functional E/PNPs minimized burst drug release (only 18%) at pH 1.2 and 6.8, and generated a sustained release at pH 7.4 thereafter. Importantly, in distribution studies in the gastrointestinal tracts of mice, E/PNPs significantly improved CSA distribution to the colon compared with PNPs or ENPs. In a mouse model of colitis, E/PNP treatment improved weight loss and colon length, and decreased rectal bleeding, spleen weight, histological scoring, myeloperoxidase activity, macrophage infiltration, and expression of proinflammatory cytokines compared with PNPs or ENPs.

Conclusion

Overall, this work confirms the benefits of CSA-loaded E/PNPs for efficiently delivering CSA to the colon, suggesting their potential for UC therapy.

pH-triggered surface charge-reversal nanoparticles alleviate experimental murine colitis via selective accumulation in inflamed colon regions

In this study, we developed pH-triggered surface charge-reversal lipid nanoparticles (LNPs), loaded with budesonide, which could precisely deliver the drug to inflamed colon segments for the treatment of ulcerative colitis. Polyethyleneimine (PEI) was used to render LNPs cationic (PEI-LNPs), and Eudragit® S100 (ES) was coated on PEI-LNPs to obtain pH-triggered charge-reversal LNPs (ES-PEI-LNPs). ES coating avoided a burst drug release under acidic conditions mimicking the stomach and early small intestine environments and showed a sustained release in the colon. The surface charge of ES-PEI-LNPs switched from negative to positive under colonic conditions owing to pH-triggered removal of the ES coating. Bioimaging of the mouse gastrointestinal tract and confocal analysis of colon tissues revealed that ES-PEI-LNPs selectively accumulated in an inflamed colon. Furthermore, ES-PEI-LNPs mitigated experimental colitis in mice. These results suggest that the pH-triggered charge-reversal LNPs could be a promising drug carrier for ulcerative colitis therapy and other colon-targeted treatments.

Predicting and explaining inflammation in Crohn's disease patients using predictive analytics methods and electronic medical record data

Crohn's disease is among the chronic inflammatory bowel diseases that impact the gastrointestinal tract. Understanding and predicting the severity of inflammation in real-time settings is critical to disease management. Extant literature has primarily focused on studies that are conducted in clinical trial settings to investigate the impact of a drug treatment on the remission status of the disease. This research proposes an analytics methodology where three different types of prediction models are developed to predict and to explain the severity of inflammation in patients diagnosed with Crohn's disease. The results show that machine-learning-based analytic methods such as gradient boosting machines can predict the inflammation severity with a very high accuracy (area under the curve = 92.82%), followed by regularized regression and logistic regression. According to the findings, a combination of baseline laboratory parameters, patient demographic characteristics, and disease location are among the strongest predictors of inflammation severity in Crohn's disease patients.

Ulcerative colitis, Crohn's disease, and irritable bowel syndrome have different profiles of extracellular matrix turnover, which also reflects disease activity in Crohn's disease

Background

Increased protease activity is a key pathological feature of inflammatory bowel disease (IBD). However, the differences in extracellular matrix remodelling (ECM) in Crohn’s disease (CD) and ulcerative colitis (UC) are not well described. An increased understanding of the inflammatory processes may provide optimized disease monitoring and diagnostics. We investigated the tissue remodelling in IBD and IBS patients by using novel blood-based biomarkers reflecting ECM remodelling.

Methods

Five ECM biomarkers (VICM, BGM, EL-NE, C5M, Pro-C5) were measured by competitive ELISAs in serum from 72 CD patients, 60 UC patients, 22 patients with irritable bowel syndrome (IBS), and 24 healthy donors. One-way analysis of variance, Mann-Whitney U-test, logistic regression models, and receiver operator characteristics (ROC) curve analysis was carried out to evaluate the diagnostic accuracy of the biomarkers.

Results

The ECM remodelling was significantly different in UC compared to CD. The best biomarker combination to differentiate UC from CD and colonic CD was BGM and VICM (AUC = 0.98, P<0.001; AUC = 0.97, P<0.001), and the best biomarker combination to differentiate IBD from IBS patients were BGM, EL-NE, and Pro-C5 (AUC = 0.8, P<0.001). When correcting for the use of immunosuppressant and elevated CRP levels (CRP>5mg/mL), correlation of Pro-C5 (r = 0.36) with CDAI was slightly improved compared to CRP (r = 0.27) corrected for the use of immunosuppressant. Furthermore, BGM and EL-NE biomarkers were highly associated with colon inflammation in CD patients.

Conclusion

ECM fragments of tissue remodelling in IBD affect UC and CD differently, and may aid in differentiating IBD from IBS (EL-NE, BGM, Pro-C5), and UC from CD patients (BGM, VICM). Formation of type V collagen is related to the level of inflammation in CD and may reflect disease activity in CD.

Biomarker Development in Chronic Inflammatory Diseases

Chronic inflammatory diseases, such as inflammatory bowel disease—namely, Crohn’s disease and ulcerative colitis—psoriasis, multiple sclerosis, rheumatoid arthritis, and many others affect millions of people worldwide, causing a high burden of disease, socioeconomic impact, and healthcare cost. These diseases have common features including autoimmune pathogenesis and frequent co morbidity.

The treatment of these chronic inflammatory diseases usually requires long-term immunosuppressive therapies with undesirable side effects. The future of chronic inflammatory disease prevention, detection, and treatment will be greatly influenced by the use of more effective biomarkers with enhanced performance. Given the practical issues of collecting tissue samples in inflammatory diseases, biomarkers derived from body fluids have great potential for optimized patient management through the circumvention of the abovementioned limitations.

In this chapter, peripheral blood, urine, and cerebrospinal fluid biomarkers used in chronic inflammatory conditions are reviewed. In detail, this chapter reviews biomarkers to fore used or emerging to be used in patients with chronic inflammatory conditions. Those include inflammatory bowel diseases, chronic inflammatory conditions of the liver, biliary tract, pancreas, psoriasis, atopic disease, inflammatory skin diseases, rheumatic diseases, demyelination, and also the chronic inflammatory component of various other diseases in general medicine—including diabetes, cardiovascular disease, renal disease, and chronic obstructive pulmonary disease.

Development of personalized medicine is closely linked to biomarkers, which may serve as the basis for diagnosis, drug discovery, and monitoring of diseases.

The use of selected neutrophil protein plasma concentrations in the diagnosis of Crohn's disease and ulcerative colitis - a preliminary report

BACKGROUND

Difficulties in diagnosis of inflammatory bowel disease (IBD) motivate the search for new diagnostic tools, including laboratory tests. The aim of this study was to evaluate concentrations of the neutrophil (NEU) proteins leukocyte elastase (HLE-α1AT), lactoferrin and calprotectin as potential biomarkers used in the diagnosis and assessment of clinical activity of Crohn's disease (CD) and ulcerative colitis (UC).

MATERIAL/METHODS

The study included 27 patients with CD, 33 patients with UC and 20 healthy controls. Plasma concentrations of calprotectin, lactoferrin and HLE-α1AT were measured using ELISA.

RESULTS

In patients with CD higher concentrations of HLE-α1AT (64.3±43.1 vs. 30.1±7.7 ng/l, P<0.001), calprotectin (151.6±97.8 vs. 69.9±22.1 ng/l, P<0.001) and lactoferrin (243.2±102.0 vs. 129.7±32.7 ng/l, P<0.001) than in the control group were found. In patients with UC higher plasma concentrations of HLE-α1AT (62.0±30.9 vs. 30.1±7.7 ng/l, P<0.001), calprotectin (149.6±72.3 vs. 69.9±22.1 ng/l, P<0.001) and lactoferrin (242.6±107.5 vs 129.7±32.7 ng/l, P<0.001) than in the control group were found. HLE-α1AT/NEU and lactoferrin/NEU ratios in patients with UC were significantly higher compared with patients with CD. Calprotectin (P=0.010) and lactoferrin (P=0.023) levels were higher in patients with the active compared with inactive phase of CD.

CONCLUSIONS

The diagnostic characteristics of plasma granulocyte protein concentrations indicate the usefulness of these tests in the diagnosis of IBD. Higher HLE-α1AT and lactoferrin/NEU ratios in patients with UC than with CD may suggest the usefulness of these ratios in differential diagnostics. Plasma calprotectin and lactoferrin levels may be useful in CD activity assessment.

The Pig PeptideAtlas: A resource for systems biology in animal production and biomedicine

Biological research of Sus scrofa, the domestic pig, is of immediate relevance for food production sciences, and for developing pig as a model organism for human biomedical research. Publicly available data repositories play a fundamental role for all biological sciences, and protein data repositories are in particular essential for the successful development of new proteomic methods. Cumulative proteome data repositories, including the PeptideAtlas, provide the means for targeted proteomics, system-wide observations, and cross-species observational studies, but pigs have so far been underrepresented in existing repositories. We here present a significantly improved build of the Pig PeptideAtlas, which includes pig proteome data from 25 tissues and three body fluid types mapped to 7139 canonical proteins. The content of the Pig PeptideAtlas reflects actively ongoing research within the veterinary proteomics domain, and this article demonstrates how the expression of isoform-unique peptides can be observed across distinct tissues and body fluids. The Pig PeptideAtlas is a unique resource for use in animal proteome research, particularly biomarker discovery and for preliminary design of SRM assays, which are equally important for progress in research that supports farm animal production and veterinary health, as for developing pig models with relevance to human health research.

Noninvasive Testing for Mucosal Inflammation in Inflammatory Bowel Disease

Biomarkers have gained increasing attention for the diagnosis and follow-up of inflammatory bowel disease (IBD). Endoscopy remains the gold standard for assessing disease activity. Biomarkers are rapid, inexpensive, and noninvasive, and can be used in different stages of the disease with high sensitivity and specificity. Calprotectin and tests for C-reactive protein are used to assess the disease activity, predict relapse, and monitor treatment response. New noninvasive tests are being studied. This review discusses current evidence for these surrogate markers, their potential clinical applications, and limitations in disease management. We highlight recent advances in IBD biomarkers and future uses.

Neutrophil anti-neutrophil cytoplasmic autoantibody proteins: bactericidal increasing protein, lactoferrin, cathepsin, and elastase as serological markers of inflammatory bowel and other diseases

Inflammatory bowel disease (IBD) is a chronic inflammatory disorder of the gastrointestinal tract comprising Crohn's disease and ulcerative colitis. Although the pathogenesis of the disease is not clearly defined yet, environmental, genetic and other factors contribute to the onset of the disease. Apart from the clinical and histopathological findings, several serological biomarkers are also employed to detect IBD. One of the most thoroughly studied biomarker is anti-neutrophil cytoplasmic autoantibody (ANCA). We herein provide an overview of the current knowledge on the use of ANCA and certain ANCA proteins, such as bactericidal increasing protein, lactoferrin, cathepsin G and elastase, as serological markers for IBD and other diseases.

Emerging role of novel biomarkers in the diagnosis of inflammatory bowel disease

There is currently no gold standard test for the diagnosis of inflammatory bowel disease (IBD). Physicians must rely on a number of diagnostic tools including clinical and endoscopic evaluation as well as histologic, serologic and radiologic assessment. The real difficulty for physicians in both primary and secondary care is differentiating between patients suffering from functional symptoms and those with true underlying IBD. Alongside this, there is always concern regarding the possibility of a missed, or delayed diagnosis of ulcerative colitis (UC) or Crohn’s disease. Even once the diagnosis of IBD has been made, there is often uncertainty in distinguishing between cases of UC or Crohn’s. As a consequence, in cases of incorrect diagnosis, optimal treatment and management may be adversely affected. Endoscopic evaluation can be uncomfortable and inconvenient for patients. It carries significant risks including perforation and in terms of monetary cost, is expensive. The use of biomarkers to help in the diagnosis and differentiation of IBD has been increasing over time. However, there is not yet one biomarker, which is sensitive of specific enough to be used alone in diagnosing IBD. Current serum testing includes C-reactive protein and erythrocyte sedimentation rate, which are cheap, reliable but non-specific and thus not ideal. Stool based testing such as faecal calprotectin is a much more specific tool and is currently in widespread clinical use. Non-invasive sampling is of the greatest clinical value and with the recent advances in metabolomics, genetics and proteomics, there are now more tools available to develop sensitive and specific biomarkers to diagnose and differentiate between IBD. Many of these new advances are only in early stages of development but show great promise for future clinical use.

Restoration of Foxp3+ Regulatory T-cell Subsets and Foxp3- Type 1 Regulatory-like T Cells in Inflammatory Bowel Diseases During Anti-tumor Necrosis Factor Therapy

BACKGROUND

A defect in regulatory T cells (Tregs) may be involved in the pathogenesis of inflammatory bowel diseases (IBD). Several subsets of human Foxp3+ Tregs (activated and resting Tregs) have now been identified, as well as an IL-10 and IFN-γ double producing Foxp3 type 1 regulatory-like T cell (Tr1L). We have quantified these Tregs in patients with active IBD and during therapy with infliximab (IFX).

METHODS

Blood samples were obtained from healthy controls (n = 54) and patients with active IBD, either before (n = 62) or during IFX therapy (n = 75). Tregs were identified by immunofluorescent staining and flow cytometry analysis. Resting and activated Foxp3+ Tregs can be differentiated from Foxp3+ effector T cells (Foxp3+ Teff) by the expression of CD45RA. Tr1L are identified as CD4+CD45RA-CD25-CD127-Foxp3- T cells.

RESULTS

A numerical deficiency of circulating resting Tregs, activated Treg cells, and Tr1L was documented in patients with active IBD. Baseline levels of these Treg subsets predicted clinical responses to IFX. We documented an upregulation of all 3 subsets during IFX therapy. Moreover, after therapy, significant differences in Treg subsets were seen between responders and nonresponders to IFX. Restoration of Tregs correlated with the clinical and biological response to IFX therapy. Trough serum levels of IFX positively correlated with the proportion of activated Treg cells and Tr1L during therapy.

CONCLUSIONS

IFX therapy, when successful, results in upmodulation of the different types of Treg cells in the blood of patients with IBD. This effect might be relevant for understanding the mechanism of action of anti-TNF agents.

Biomarkers of Inflammation in Inflammatory Bowel Disease

Recent observations suggest that subjective measures of disease activity in inflammatory bowel disease (IBD) are often misleading. Objective measures of inflammation are more closely associated with important long-term outcomes, but often depend upon invasive and costly procedures such as ileocolonoscopy and cross-sectional imaging by computed tomography or magnetic resonance imaging. Noninvasive, accurate, and inexpensive measures of intestinal inflammation would allow clinicians to adopt widely the paradigm of adjusting therapies with a goal of controlling inflammation. Blood, stool, and urine markers have all been explored as indicators of intestinal inflammation in IBD, and although none has been universally adopted, some have been well-characterized, and others hold great promise. Serum C-reactive protein and fecal calprotectin are among the best-studied noninvasive biomarkers of inflammation in IBD, and their test characteristics have been described in the setting of differentiating IBD from irritable bowel syndrome, for grading inflammation, to describe the response to therapy, and in demonstrating recurrent inflammation after medical or surgically induced remission. High-throughput research platforms, including gene expression arrays, metabolomics and proteomics, are also being applied to the discovery of novel biomarkers of inflammation. It is certain that biomarkers of inflammation will attain growing importance in the clinic as we strive for more effective and cost-effective strategies to treat patients with IBD.

Fragments of Citrullinated and MMP-degraded Vimentin and MMP-degraded Type III Collagen Are Novel Serological Biomarkers to Differentiate Crohn's Disease from Ulcerative Colitis

BACKGROUND AND AIMS

A hallmark of inflammatory bowel disease [IBD] is chronic inflammation, which leads to excessive extracellular matrix [ECM] remodelling and release of specific protein fragments, called neoepitopes. We speculated that the biomarker profile panel for ulcerative colitis [UC] and Crohn's disease [CD] represent a heterogeneous expression pattern, and may be applied as a tool to aid in the differentiation between UC and CD.

METHODS

Serum biomarkers of degraded collagens I, III-IV [C1M, C3M, and C4M], collagen type 1 and IV formation [P1NP, P4NP], and citrullinated and MMP-degraded vimentin [VICM] were studied with a competitive ELISA assay system in a cohort including 164 subjects [CD n = 72, UC n = 60, and non-IBD controls n = 32] and a validation cohort of 61 subjects [CD n = 46, and UC n = 15]. Receiver operating characteristic curve analysis and logistic regression modelling were carried out to evaluate the discriminative power of the biomarkers.

RESULTS

All biomarkers were corrected for confounding factors. VICM and C3M demonstrated the highest diagnostic power, alone, to differentiate CD from UC with an area under the curve [AUC] of 0.77 and 0.69, respectively. Furthermore, the biomarkers C1M [AUC = 0.81], C3M [AUC = 0.83], VICM [AUC = 0.83], and P1NP [AUC = 0.77] were best to differentiate UC from non-IBD. The best combinations of biomarkers to differentiate CD from UC and UC from non-IBD were VICM, C3M, C4M [AUC = 0.90] and VICM, C3M [AUC = 0.98] respectively.

CONCLUSIONS

Specific extracellular matrix degradation markers are elevated in IBD and can discriminate CD from UC and UC from non-IBD controls with a high diagnostic accuracy.

A think tank of the Italian society of colorectal surgery (SICCR) on the surgical treatment of inflammatory bowel disease using the Delphi method: Crohn's disease

The management of Crohn's disease (CD) requires extensive expertise. Many treatment options are available, and surgery still plays a crucial role. In recent years, many medical societies have provided surgeons and gastroenterologists dealing with CD with authoritative guidelines. However, a certain degree of variation can be observed in these papers, and application of guidelines in clinical practice should be improved. The Italian society of colorectal surgery (SICCR) promoted the project reported here, which consists of a think tank of Italian colorectal surgeons to address the surgical aspects of CD management. Members of the society were invited to express their opinions on several items proposed by the writing committee, based on evidence available in the literature. The results are presented, focusing on relevant points. The present paper is not an alternative to available guidelines; rather, it offers a snapshot of the attitudes of SICCR surgeons about the surgical treatment of CD. The management of CD is, by necessity, patient-tailored, and it is based on clinical data and surgeon's preference, but the committee was able to identify some points of major disagreement and suggested strategies to improve quality of available data and acceptance of guidelines.

Neutrophil Extracellular Traps in Ulcerative Colitis: A Proteome Analysis of Intestinal Biopsies

BACKGROUND

The etiology of the inflammatory bowel diseases, including ulcerative colitis (UC), remains incompletely explained. We hypothesized that an analysis of the UC colon proteome could reveal novel insights into the disease etiology.

METHODS

Mucosal colon biopsies were taken by endoscopy from noninflamed tissue of 10 patients with UC and 10 controls. The biopsies were either snap-frozen for protein analysis or prepared for histology. The protein content of the biopsies was characterized by high-throughput gel-free quantitative proteomics, and biopsy histology was analyzed by light microscopy and confocal microscopy.

RESULTS

We identified and quantified 5711 different proteins with proteomics. The abundance of the proteins calprotectin and lactotransferrin in the tissue correlated with the degree of tissue inflammation as determined by histology. However, fecal calprotectin did not correlate. Forty-six proteins were measured with a statistically significant differences in abundances between the UC colon tissue and controls. Eleven of the proteins with increased abundances in the UC biopsies were associated with neutrophils and neutrophil extracellular traps. The findings were validated by microscopy, where an increased abundance of neutrophils and the presence of neutrophil extracellular traps by extracellular DNA present in the UC colon tissue were confirmed.

CONCLUSIONS

Neutrophils, induced neutrophil extracellular traps, and several proteins that play a part in innate immunity are all increased in abundance in the morphologically normal colon mucosa from patients with UC. The increased abundance of these antimicrobial compounds points to the stimulation of the innate immune system in the etiology of UC.