bluuebunny/crossref_metadata_2025 huggingface dataset:
DOP67 CKD-506, a selective histone deacetylase (HDAC) 6 inhibitor, ameliorates colitis through regulation of NF-kB and AP-1 signalling pathway
Authors: Shin J , Ha N , Bae D , Lee Y J , Choi Y I , Ryu K H , Youn G S , Park J
Published: January 2020

Background

HDAC6 is a stress-inducible gene and highly expressed in pathological conditions as well as inflammatory bowel disease. Immuno-modulatory functions of HDAC6 inhibitors are well established and proposed therapeutic effects for autoimmune diseases through regulation of Treg cell function and inflammation. Moreover, HDAC6 inhibitors regulate inflammatory cytokines and chemokines, neutrophil activities, and epithelial regeneration in colitis models. CKD-506, a potent and selective oral HDAC6 inhibitor, is generally safe and well-tolerated in human, and is now investigating the efficacy in patients with rheumatoid arthritis. Herein, for future investigation with IBD, we identified molecular action mechanisms of CKD-506 involved in anti-colitis effects.

Methods

Mouse peritoneal macrophages or Raw264.7 cells were transfected with HDAC6 overexpression plasmid or empty vector as control. Cells were cultured in the presence or absence of 0.03~3 μM CKD-506, and the expression and production of inflammatory mediators were determined by RT–PCR and ELISA respectively. For reporter assays, Raw264.7 cells were transfected with pNF-kB-luc or pAP-1-luc plasmid and luciferase activity in cell lysates was determined by a luminometer. Signalling molecules in HDAC6 overexpressed cells were checked by immunoblot analysis. For the efficacy test of CKD-506, we used DSS-, TNBS-, Piroxicam (IL-10−/−)-, and adaptive T-cell transfer (RAG1−/−)-mediated colitis animal models. Colitis animals were treated with 1 to 100 mg/kg of CKD-506 and analysed disease activities and inflammatory mediators.

Results

In vivo, CKD-506 strongly inhibited disease activities in DSS-, TNBS-, Piroxicam-, and adaptive T-cell transfer-mediated colitis. In the chemical-induced colitis model, the expression of cell adhesion molecules and chemokines such as IP-10 and also infiltration of immune cells to colon tissues were reduced in CKD-506 treated mice. In vitro, HDAC6 overexpression strongly induced ROS and NADPH oxidase activity in Raw264.7 cells and CKD-506 significantly and dose-dependently inhibited HDAC6-mediated ROS and NADPH activity. Moreover, CKD-506 inhibited the production of pro-inflammatory cytokines and chemokines which are up-regulated in HDAC6 overexpressed mouse peritoneal macrophages or Raw264.7 cells. In promoter assay, HDAC6 overexpression highly induced NF-kB and AP-1 activity and CKD-506 strongly and dose-dependently inhibited both signalling pathways.

Conclusion

These data provide insight that CKD-506, a selective HDAC6 inhibitor, has anti-inflammatory and anti-colitis effects through regulation of NF-kB and AP-1 signalling pathway. Therefore, CKD-506 may provide beneficial effects in patients with Crohn’s disease and ulcerative colitis.
DOP77 Ustekinumab is associated with better effectiveness outcomes when compared with vedolizumab in Crohn’s disease patients with prior anti-TNF failure: comparative effectiveness study from the ICC Registry
Authors: Biemans drs V , van der Woude J , Dijkstra G , van der Meulen- de Jong A , Löwenberg M , de Boer N , Oldenburg B , Srivastava N , Jansen J , Bodelier A , West R , de Vries A , Haans J , de Jong D , Hoentjen F , Pierik M
Published: January 2020

Background

Both vedolizumab and ustekinumab can be considered for the treatment of Crohn’s disease (CD) when anti-TNF treatment fails. However, head-to-head trials are currently not available or planned in the near future. The aim of this study was to compare vedolizumab and ustekinumab in CD patients using a quasi-experimental study design in a prospective registry specifically developed for comparative studies.

Methods

CD patients who failed anti-TNF treatment and started vedolizumab or ustekinumab in standard care as second-line biological and naïve to the latter two therapies, were identified in the observational prospective ICC Registry. Corticosteroid-free clinical remission (Harvey Bradshaw Index ≤4), biochemical remission (C-reactive protein ≤5 mg/l and faecal calprotectin ≤250 µg/g), combined corticosteroid-free clinical and biochemical remission, and safety outcomes were compared after 52 weeks of treatment. To adjust for confounding and selection bias, we used multiple logistic regression (correcting for current smoker, disease duration, complicated disease (stricturing or penetrating behaviour), prior CD-related surgery, number of prior anti-TNF treatments, HBI at baseline and biochemical disease at baseline) and propensity score matching (variables include the same variables as logistic regression analysis with addition of disease location and behaviour, corticosteroid and immunosuppressant use at baseline).

Results

In total, 128 vedolizumab- and 85 ustekinumab-treated patients fulfilled the inclusion criteria. By using propensity score matching, 69 vedolizumab-treated patients were matched with 69 ustekinumab-treated patients. After adjusting for confounders, ustekinumab-treated patients were more likely to achieve corticosteroid-free clinical remission (OR: 2.56, 95% CI: 1.35–4.87, p = 0.004), biochemical remission (OR: 2.22, 95% CI: 1.04–4.74, p = 0.040), and combined corticosteroid-free clinical and biochemical remission (OR: 2.58, 95% CI: 1.15–5.78, p = 0.022), while safety outcomes (infections: OR: 1.26, 95% CI: 0.63–2.54, p = 0.517; adverse events: OR: 1.33, 95% CI: 0.62–2.81, p = 0.464; hospitalisations: OR: 0.67, 95% CI: 0.32–1.39, p = 0.282) were comparable between the two groups. The propensity score matched cohort showed comparable results.

Conclusion

In this prospective, comparative analysis ustekinumab was associated with higher effectiveness outcomes of ustekinumab when compared with vedolizumab. Safety outcomes were comparable after 52 weeks of treatment in CD patients who have failed anti-TNF treatment.
P014 Identification of Crohn’s disease immunopathotypes
Authors: Baer H M , MacDonald E , Ferguson A , Scott A M , Khan M I , Bain K A , Ijaz U Z , Cole J , Ramanujam M , Nibbs R J B , Gaya D R , Milling S W F
Published: January 2020

Background

Crohn’s disease (CD) is a chronic inflammatory gastrointestinal condition, with globally increasing incidence. Patients with CD suffer from a loss of tolerance towards their commensal microbiota causing an aberrant immune response, occurring in a protracted relapse and remission cycle. Although a variety of frontline therapies is currently available, including targeted therapies such as biologic drugs, 30–40% of CD patients still require surgery to manage the disease. At present, the immunobiology of CD is not fully understood. However, differences in immune responses between patients might play an important role in diverse treatment responses. The aim of this study was to identify differences in peripheral and local immune responses of CD to understand differences in disease behaviour and treatment outcome.

Methods

Peripheral blood mononuclear cells and plasma were isolated from whole blood of a cross-sectional CD patient cohort (nCD = 12) and normal controls (NC, nNC = 28). Flow cytometry analysis and multiplex assays were used to quantify immune cell populations and cytokine levels, respectively. The local immune response was analysed by bulk RNA sequencing of mucosal colonic biopsies either from inflamed CD or normal tissue. Gene signatures were then followed up by validation in publicly deposited gene expression datasets (nCD = 36, nNC = 24), and by measurement of specific proteins using our archived samples.

Results

Peripheral immunophenotyping of the initial cross-sectional study displayed three different types of CD patients, characterised by either a decrease in leukocyte populations, an increase of cytokines, or a change in both. Analysis of the RNAseq data derived from colonic biopsies revealed four distinct clusters in genes associated with the immune response in CD patients. Further pathway analysis showed one cluster with an enriched B cell signature and another cluster with an elevated macrophage and neutrophil response. We utilised publicly available gene expression datasets to validate these signatures in a larger cohort and identified a selection of patients with an up-regulated pro-inflammatory macrophage response. Using correlation analysis, we suggest an immunopathotype with increased macrophage activation which is potentially associated with a more severe form of the disease.

Conclusion

We have identified distinct immunopathotypes in both the peripheral and local immune response of CD patients. Further investigation will correlate these distinct immune responses in CD with clinical parameters, to understand associations between diverse treatment responses and disease behaviours.
P031 Therapeutic effect of OPS-2071 in a murine model of Crohn’s disease and in in vitro anti-inflammatory assays
Authors: Takagi H , Sato M , Kazuyuki F , Shibuya I , Oka D , Yamaya N , Inagaki K
Published: January 2020

Background

OPS-2071 is a novel fluoroquinolone that is currently in Phase 2 clinical trials for the evaluation of Crohn’s disease (CD) as an add-on therapy to standard of care. OPS-2071 has broad and potent antibacterial activity with low systemic absorption. It was previously investigated for the treatment of enteric infections, including Clostridium difficile. CD is an immune-mediated condition of unknown aetiology; however, studies suggest that an abnormal immune response against certain intestinal bacteria may trigger the development of chronic inflammation. In this study, we have evaluated the effect of OPS-2071 on both the murine T-cell-mediated colitis as well as its in vitro effect on the activity of immune cells.

Methods

Transfer of naïve T cells (CD4+CD62L+CD44−) into immunodeficiency mice induces autoimmune colitis. Two weeks following T-cell transfer, OPS-2071, sulfasalazine and anti-IL12/23 p40 antibody were administered for 3 weeks, followed by assessment of efficacy evaluation by histological score and inflammatory index. In vitro inhibitory action for TNF-α production was assayed using LPS-stimulated human peripheral blood cells and THP-1 macrophages. The effect on T-cell activation and cytokine production (TNF-α, IFN-γ) was examined using anti-CD2/CD3/CD28 antibody-loaded beads-stimulated human peripheral blood mononuclear cells. In vitro activity against bacteria considered to be a potential cause of IBD such as M. avium sub. paratuberculosis, Klebsiella pneumonia, etc., was also tested.

Results

OPS-2071 and anti-IL12/23 p40 antibody significantly reduced both histological score (control: 9.0, OPS: 4.7, anti-IL12: 4.3, p < 0.01) and inflammatory index (control: 58.3 ± 3.7 mg/cm, OPS: 25.9 ± 1.4 mg/cm, anti-IL12: 41.1 ± 2.4 mg/cm, p < 0.01) at a dose of 10 and 25 mg/kg, respectively. OPS-2071 suppressed TNF-α production in T cells, as well as macrophage activity in a dose-dependent fashion. OPS-2071 also suppressed human T-cell activation and proliferation. At high OPS-2071 concentrations, these effects were comparable to prednisolone. The minimum inhibitory concentration against IBD-related bacteria for: OPS-2071, ciprofloxacin, and metronidazole were 0.015–0.5, 0.25–8 and 0.03–>128 mg/ml, respectively.

Conclusion

OPS-2071 demonstrated significant therapeutic effect on colonic inflammation, suppressed TNF-α production in vitro and showed in vitro activity against bacteria related to CD. From these in vitro results, it can be concluded that OPS-2071 has anti-inflammatory activity, independent of its antibacterial activity. The dual effects demonstrated by this novel agent, OPS-2071, provided a rationale for exploring the impact of this compound on human CD in clinical trials.
P036 A novel p53-mediated mouse model of inflammatory bowel disease-associated colorectal cancer
Authors: Churchhouse A M , Billard C V , Arends M J , Myant K B
Published: January 2020

Background

Current mouse models of colitis-associated cancer often utilise a combination of APC mutation, Dextran sulphate sodium (DSS) and azoxymethane administration. However, only 13% of human inflammatory bowel disease (IBD)-associated cancers is associated with an APC mutation1. Instead, they are frequently associated with mutation of p53 (occurring in 63% of human cancers1). Whilst some models of IBD-associated cancer using either global p53 loss or mutant p53 have been described, we felt that a more pathophysiologically relevant model would be represented using p53 loss solely in the colonic epithelium.

Methods

Colonic epithelial p53 floxing in Vil-CreERT2p53fl/fl mice was achieved through intraperitoneal injection of 120 and 80 mg/kg tamoxifen on two consecutive days. After 16 days, mice were started on a chronic DSS treatment protocol. Chronic DSS-induced colitis involved three 5-day cycles of low-dose DSS (1.5% initially and subsequently 1% for the remaining two cycles), interspersed with normal drinking water for 2 weeks to facilitate recovery. After three cycles of DSS, mice were aged to 164 days.

Results

At 164 days post induction of DSS, 100% of mice had developed adenomata with low-grade dysplasia (n = 4). Adenomata in 50% of these mice (n = 2) also had features of high-grade dysplasia. There were between one and three adenomata in each animal. No features of invasive adenocarcinoma were demonstrated. There was partial β-catenin nuclear localisation in these tumours. Background chronic colitis was evident, even though the experiment ended over 3 months after the DSS treatment finished.

Conclusion

To the best our knowledge, this is the first mouse model of colitis-associated cancer using p53 loss in the colonic epithelium together with chronic colitis induction using DSS. The experiment ended over 3 months after the DSS treatment finished, showing that the resultant chronic colitis can persist long after the initial insult is given. The fact that β-catenin is partially, but not fully nuclear localised suggests an alternative pathway to tumour formation in this p53fl/fl model, and may therefore be more pathophysiologically relevant to human IBD-associated colorectal cancers. Further work is now being carried out to both validate and further evaluate this novel mouse model, including assessment of stem cell dynamics in response to colitis in the context of p53 loss.

Reference
P052 Nuclear magnetic resonance metabolomic profiling of IBD patients under anti-TNF treatment. Are the pathways network deregulated?
Authors: Notararigo S , Martin-Pastor M , Dominguez Munoz J E , Barreiro-de Acosta M
Published: January 2020

Background

The deregulation of immune system cell response implies loss of T-cell apoptosis, high rate of proinflammatory cytokines production and subsequent exacerbate activation of TNF-α pathway. The use of biologic antibody decrease inflammation rate and symptoms, but it remains unclear if it has a direct effect on the pathways activation/inactivation on peripheral blood mononuclear cells (PBMCs). The aim of this study is evaluate the role of nuclear magnetic resonance spectroscopy (NMR) applied to the metabolomic study of serum samples isolated from fresh blood from inflammatory bowel disease (IBD) patients under IFX treatment to understand the activated/inactivated pathways of PBMCs.

Methods

A case–control study was performed. Inclusion criteria were IBD patients under IFX treatment. Blood samples were obtained in Crohn’s disease (CD) and ulcerative colitis (UC) patients before IFX and in healthy controls (CTRL). CD patients were divided into subgroups according to the gut affected, in Ileocolic (IC), ileum and colon. NMR samples of the serum were collected and measured according to Standard Operation Procedures. Three types of NMR spectra were measured for each serum sample (1Hnoepresat, 1Hcpmgpresat and 1HDfilterpresat). The signal in each NMR spectrum was integrated in a series of equidistant little portion of the spectrum called buckets of a constant width of 0.04 ppm, covering the complete 1H NMR spectral window from −5 to 14 ppm. Buckets in regions depleted from signal at the two extremes of the spectrum were discarded as well as those in the proximity of the water peak at ca. 4.7 ppm which was affected by the presaturation. The vectors corresponding to a number of samples of two or more groups can be rapidly analysed using Multivariant Statistical Analysis methods.

Results

Twenty-two IBD patients (12 CD and nine UC) were included, 10 CTRL were also included. The metabolomic analyses of the NMR spectra of the serum of the different patients and control groups by the fingerprinting and targeting profiling strategies provided OPLS-DA statistical models (Figure 1) that permitted the successful classification of certain groups of samples which are summarised in Table 1.

Conclusion

The results of this pilot NMR metabolomic study of serum samples of IBD found a series of spectral fingerprints that are able to discriminate between groups of patients CTRL and CD, which underlines its potential use for the diagnosis of the disease.
P059 Cytokine responsive transcriptional networks in inflammatory bowel disease
Authors: Treveil A , Pavlidis P , Tsakmaki A , Bewick G , Korcsmaros T , Powell N
Published: January 2020

Background

Interactions between the immune system and the intestinal epithelium play an important role in the pathogenesis of chronic immune mediated inflammatory diseases, including inflammatory bowel disease (IBD). In IBD, debilitating symptoms and complications including abscesses and cancer are associated with aberrant cytokine production and resulting intestinal epithelial damage. Despite the advent of biological therapies targeting key pathogenic cytokines, like tumour necrosis α (TNF), only 18% of IBD patients will achieve complete disease control and mucosal healing. Here, we provide new insights into the epithelial response to cytokines using network analysis of transcriptomics data from colonic organoids (colonoids).

Methods

We generated an atlas of the transcriptomic effects of cytokines by treating human-derived colonoids with IFNg, IL13, IL9, IL17A and TNF (independently). By integrating the observed transcriptional changes with previously published signalling and regulatory interactions, we generated causal networks to elucidate the effect of cytokine cues on epithelial cells. These networks comprised experimentally verified protein–protein and transcription factor (TF)–target gene interactions, forming signalling pathways linking cytokines to TFs and from TFs to differentially expressed genes.

Results

With this analysis, we identified previously unrecognised levels of shared and distinct transcriptional regulation of colonic epithelial function by different cytokines. While IL9 had a negligible impact on the transcriptome, the transcripts with differential expression induced by IFNg, IL13, IL17A or TNF were consistent with their recognised function in other tissues. IFNg and TNF exhibited similar magnitude and directional effects on key immune pathways while IL13 had the opposite effect. Using a network approach, we found that regulatory effects of cytokines are primarily transduced through unique signalling routes, some of which converge on the same key transcription factors; CEBPA, E2F1, E2F2, ETS1, FOS, IRF1 and MAZ. We observed independent regulatory mechanisms of the different cytokines as well as complementarity in the epithelial responses regulated by different canonical cytokines.

Conclusion

The generated cytokine transcriptional atlas provides a unique insight into the immune-epithelial interactome by allowing the identification of shared and distinct transcriptional pathways across different types of immunity at the mucosal barrier. In addition, it provides the unique opportunity to study cytokine responses in the context of human disease and generate novel hypotheses.
P063 B-cell receptor signalling in lymphoid tissues may be regulated by CEACAM1
Authors: Nagaishi T , Tsugawa N , Yamada D , Watabe T , Onizawa M , Watanabe M
Published: January 2020

Background

It has been recently shown that the carcinoembryonic antigen-related cell adhesion molecule 1 (CEACAM1) expressed in T cells may regulate immune responses in the gut. Moreover, it has also been reported that the treatments with either an agonistic monoclonal antibody (mAb) or natural ligands for this molecule can suppress colitis severity in murine models of inflammatory bowel diseases (IBD). On the other hand, in addition to T cells, B cells are also an important population in the gut-associated lymphoid tissues (GALT) that orchestrate mucosal homeostasis. However, the role of CEACAM1 in B cells has not been elucidated.

Methods

We analysed primary B-cell subsets in the lymphoid tissues of wild-type C57BL6 mice as well as a murine B-cell line, A20, to determine the expressions and functions of CEACAM1.

Results

FACS analysis of the lymphocyte subsets isolated from secondary lymphoid tissues such as spleen, mesenteric lymph nodes and Peyer’s patches of C57BL6 revealed higher expression level of CEACAM1 on B-cell surface than that of T cells. Bone marrow analysis showed that such CEACAM1 expression was increased during maturation and differentiation process of B cells. When isolated splenic B cells were stimulated with LPS, anti-CD40 or anti-μ chain Abs in the presence of agonistic anti-CEACAM1 mAb, the usual increased cytokine productions (such as IL-4 and IL-5 by activation via B cell receptor (BCR) signalling) were specifically suppressed by CEACAM1 signalling rather than B-cell activations via either TLR4 or CD40 signalling. Immunofluorescent studies using confocal microscopy revealed co-localisation of CEACAM1 and BCR when B cells were activated with anti-μ chain Ab. Given these results, A20 cells were transfected with CEACAM1 cDNA. Biochemical analysis showed that an inducible overexpression of CEACAM1 suppressed the BCR signalling in these cells when compared with that of vector alone-transfected control. Moreover, the overexpression of CEACAM1 in these cells resulted in reduced expressions of activation markers such as CD69, CD80, CD86, MHC-I and -II on the cell surface. These observations were associated with decreased Ca2+ influx and suppressed cytokine production by the overexpression of CEACAM1 after BCR signal activation.

Conclusion

These results suggest that CEACAM1 can regulate B-cell activation and differentiation specifically via BCR signalling in the lymphoid tissues. Therefore, this molecule can be a therapeutic target in IBD by regulating of both T-cell and B-cell activation in GALT.
P081 The structure of the proteomic profile and gut microbiota in patients with primary immunodeficiency, common variable immunodeficiency and inflammatory bowel disease
Authors: Iakovlev A A , Volkov A , Bashtovaya O , Shcherbakova I , Ghazudin T , Leonova G , Tarasova G
Published: January 2020

Background

Infringement of intestinal microbiota in patients with primary immunodeficiency (PID), common variable immunodeficiency (CVID) and ulcerative colitis (UC) continues to be studied. The aim of the research is a comprehensive study of the structure of gut microbiota and mucosal protein profile (MPP) in patients with PID, CVID and UC in different phases of the disease course.

Methods

The research included 15 patients with PID, 22 CVID and 46 UC (28 with relapse and 18 with persistent remission of the disease), control group—20 healthy volunteers. Estimation of gut microbiota was performed by bacteriological seeding, hydrogen breath test (HBT) with lactulose. Content of short-chain fatty acids (SCFAs) and microbial lipid markers (MLM) in faeces and colon mucosa was determined by gas–liquid chromatographic and gas chromatography–mass spectrometry (GC–MS). MPP was based on isoelectric focusing techniques (SDS–PAGE, 2DGE). Mass spectrograms were obtained using MALDI-TOF-MS/MS (Bruker, USA).

Results

HBT showed a 4.5-, 8- and 11-fold increase in hydrogen production on a 150th-minute study. SCFA showed a 6-, 9- and 11-fold decrease in propionic and butyric acids, mainly in patients with PID and UC: 0.2 + 0.1, 0.14 + 0.03 and 0.04 + 0.02 mg/g, respectively. Microbiological analysis showed a decrease in titers of E. coli, bifido- and lactobacilli on average 4.6 + 0.8 Lg. The conditionally pathogenic microflora was represented by E. coli, lactose-negative strains (n = 51,105/g) and haemolytic strains (n = 34,104/g, Proteus spp. (n = 48,105/g), Staphylococcus spp. (n = 29,105–6/g), Candida (n = 51,104–6/g) and Clostridium spp. (n = 38,104/g) in stool culture. MLN GS-MS results showed a 5.5-, 3- and 6-fold increase in total bacterial load in patients with PID, CVID and UC, respectively, which was represented by resident anaerobic microflora: Streptococcus mutants, Clostridium difficile, Candida albicans. Results of MPP (detection rate of 75% or more) of the colon mucosa in patients with PID were detected: 1, 2, 4 okkludin, kininogen 1, interleukin-1B, interleukin 8, B2-glycoprotein, heat shock protein 27, in patients with CVID—translational elongation factor, apolipoprotein C-III. In patients with UC—NF-kB, alipoprotein C-III, TNF-α, interleukin-2 and 8 were presented.

Conclusion

In patients with PID, CVID and UC markers of colon excess growth and significant decrease in SCFA are recorded during the relapse period. MPP in patients with PID, CVID and UC was characterised by proteins characteristic of inflammation, apoptosis, proliferation and proteins reflecting the activity of the autoimmune process. Patients with UC in the remission have recovery trend of gut microbiota, production of SCFA, disappearance of specific components of altered MPP.
P083 Characterisation of T-cell receptor repertoire patterns of circulating a4b7 positive memory T cells in ulcerative colitis
Authors: Gamliel A , Werner L , Salamon N , Pinsker M , Weiss B , Shouval D
Published: January 2020

Background

Memory T cells play an important role in mediating inflammatory responses in IBD. The integrin a4b7 is highly expressed on activated T cells, and is thought to direct homing of lymphocytes to the intestine, following its binding to MADCAM-1 expressed exclusively on intestinal endothelial cells. Since UC is characterised by oligoclonal expansion of specific T-cell clonotypes, we hypothesised that circulating memory T cells with gut-homing potential would exhibit unique T-cell receptor repertoire features.

Methods

Peripheral blood mononuclear cells were collected from 5 control subjects and 6 pediatric patients with active UC. Following CD3 MACS sorting cells were FACS sorted into a4b7 positive and a4b7 negative CD3+CD45RO+ memory T cells. DNA was Isolated from each subset and subjected to next-generation sequencing of the TCRB. This high-throughput platform employs massive parallel sequencing to process millions of rearranged T-cell receptor (TCR) products simultaneously, and permits an in-depth analysis of individual TCRs at the nucleotide level. Comparisons of different indices of diversity, CDR3 length and clonal biochemical characteristics were performed between a4b7 positive and a4b7 negative populations for each subject, and between controls and UC patients.

Results

PBMCs were isolated from active UC patients during endoscopic assessment. Four patients had a Mayo endoscopic score of 2, and two patients had a score of 1. Only one patient was treated with an immunosuppressive medication (azathioprine), and five out of six patients were treated with 5ASAs. Percentages of memory T cells (43.8 ± 12.3% vs. 32.2 ± 13.1%, p = 0.17) and a4b7 positive T cells (33.6 ± 15.7% vs. 36.0 ± 17.6%, p = 0.81) were comparable between controls and UC patients. Interestingly, a4b7 positive memory T cells displayed a polyclonal distribution, in both control subjects and in UC patients, without expansion of specific clones. Different indices of diversity, including shanon’s H, clonality index and entropy, were similar among controls and patients, both for a4b7 positive and a4b7 negative populations. Finally, clonal overlap between a4b7 positive and a4b7 negative memory T cells, for each subject was high, ranging between 30–50% for controls and 27–48% for UC patients.

Conclusion

a4b7 expressing memory T cells exhibited a polyclonal repertoire in both control subjects and patients with active UC, with high rates of overlap with a4b7 negative memory T cells. Our study, along with additional recent reports, challenge the dogma of the importance of a4b7 expression for T-cell migration to the gut, and may suggest that vedolizumab’s suppresses intestinal inflammation by blocking the trafficking of innate immune subsets.
P095 PD-1 expressing T cells in patients with different types of colitis
Authors: Roosenboom B , Horjus Talabur Horje C , Smids C , Leeuwis J W , Van Koolwijk E , Groenen M , Wahab P , Van Lochem E
Published: January 2020

Background

Immunotherapy-related colitis is a frequent adverse event in patients with malignancies, treated with inhibitors targeting programmed death-1 (PD-1). This treatment leads to enhancement of lymphocyte activity, thereby generating antitumor T-cell activity. The role of PD-1+ T cells in the pathophysiology of different types of colitis is unclear. Therefore, we aimed to study the presence of PD-1+ T cells in inflammatory bowel disease (IBD), infectious colitis and healthy controls compared with anti-PD-1-related colitis.

Methods

We performed a prospective cohort study. Newly diagnosed patients with ulcerative colitis (UC, n = 51), Crohn’s disease (CD, n = 29), infectious colitis (n = 4), anti-PD-1-related colitis (n = 5) and healthy controls (n = 6) were included. Baseline colonic biopsy specimens were collected for immunohistochemistry identifying PD-1+ and PD-L1+ lymphocytes in the epithelium and lamina propria separately and for immunophenotyping by flow cytometry identifying PD-1+ T-cell subsets.

Results

Using immunohistochemistry, PD-1 was not present on lymphocytes in the epithelium of patients with any type of colitis, nor in healthy controls. Of all lymphocytes in the lamina propria, % PD-1 expression was 40% in UC, 5% in infectious colitis, 3% in anti-PD-1-related colitis and 0% in healthy controls. PD-L1 was expressed on lymphocytes in the epithelium and lamina propria of UC patients (12.5% and 40%) and in infectious colitis (1% and 30%), whereas in anti-PD-1-related colitis (0% and 15%) and healthy controls (0% and 15%) no PD-L1+ lymphocytes were demonstrated in the epithelium. Flowcytometry showed higher percentages of PD-1+ T cells in biopsy specimens of UC patients (25.2% (IQR 17.9–35.6)) compared with all other groups; CD patients (13.5% (5.0–25.3), p = 0.001), infectious colitis (9.8% (4.7–17.4), p = 0.005), anti-PD-1-related colitis (1.5% (1.1–2.1), p = 0.001) and healthy controls (14.3% (4.9–28.2), p = 0.08). In IBD and infectious colitis, the majority of PD-1+ T cells were CD4+ (84.8% (76.5–90.5), while in anti-PD-1-related colitis the majority of PD-1+ T cells were CD8+ (76.2% (68.5–82.1)). PD-1+ T cells in all patient groups were mainly effector T cells (CD45Ro+).

Conclusion

In patients with different types of colitis and in healthy controls, PD-1 was only expressed on T cells in the lamina propria and not in the epithelium. The percentage of PD-1+ T cells was significantly higher in patients with UC compared with patients with CD or infectious colitis and healthy controls. As expected PD-1+ T cells were nearly absent in patients with anti-PD-1-related colitis.
P099 Neutrophil gelatinase-associated lipocalin (NGAL) as biomarker in collagenous colitis
Authors: Walaas G A , Bakke I , Granlund A V , Escuderos-Hernândez C , Bruland T , Røyset E S , Thorsvik S , Münch A , Østvik A E , Sandvik A K
Published: January 2020

Background

Neutrophil gelatinase-associated lipocalin (NGAL) is upregulated in the intestinal epithelium in inflammatory bowel disease and is a biomarker with sensitivity and specificity comparable to calprotectin. Microscopic colitis (MC) is a common cause of chronic, watery diarrhoea and represents an inflammatory bowel disease with unknown aetiology and pathogenesis. Diagnosis depends on histological evaluation of colonic biopsies. There is a need for non-invasive diagnostic tools, and this study examines the potential of NGAL as a biomarker in collagenous colitis (CC) as one of the two main histological forms of MC.

Methods

Gene expression of colonic biopsies (n = 9/group) from active CC, budesonide treated CC in clinical remission and healthy controls (HC) was explored by RNA-sequencing analysis. An extended set of colonic biopsies (n = 17–29/group) was also examined by immunohistochemistry (IHC) and in situ hybridisation (ISH). Faecal samples from the same patient groups, in addition to samples from patients with irritable bowel disease diarrhoea (IBS-D), were assayed for NGAL and calprotectin (Calpro) by ELISA.

Results

The NGAL gene, LCN2, was significantly upregulated in active CC vs. HC (log2 2.694, fold change 6.471) adjusted p-value 0.005) and in pairs of active CC vs. treated CC LCN2 was significantly downregulated (log2 0.345, fold change −1.536), adjusted p-value 0.04). Both immunohistochemical staining and in situ hybridisation identified increased NGAL expression localised to the mucosal epithelial cells in active CC, compared with an almost absent and scarce expression in HC and treated CC, respectively. There were great individual differences in faecal concentrations of NGAL particularly in the active CC group, but the NGAL concentrations were significantly increased compared with HC, IBS-D and treated CC.

Conclusion

NGAL is upregulated and located mainly to the colonic epithelium of active CC and reduced in clinical remission after budesonide treatment. This is also reflected in the faecal concentrations. We propose NGAL as a valuable biomarker in evaluating the inflammatory activity related to CC and a potential faecal biomarker discriminating CC from IBS-D.
P105 Glutathione S-transferase theta 1 protects against colitis through goblet cell differentiation via interleukin-22
Authors: Kim J H , Ahn J B , Kim D H , Kim S , Ma H W , Che X , Seo D H , Kim T I , Kim W H , Cheon J H , Kim S W
Published: January 2020

Background

The enzyme glutathione S-transferase theta 1 (GSTT1) is involved in detoxifying chemicals, including reactive oxygen species (ROS). Oxidative stress plays a key role in the pathogenesis of inflammatory bowel disease (IBD). Although mutation of the GSTT1 gene increases IBD susceptibility, the underlying mechanisms remain unexplained.

Methods

The Gstt1 gene was intrarectally or intraperitoneally delivered to mice with dextran sodium sulphate (DSS)-induced colitis. The GSTT1 gene was knocked down or knocked out using short interfering RNA or genome editing, respectively. Protein and mRNA expression and differentiation of goblet cells were evaluated.

Results

We identified decreased expression of GSTT1 in inflamed tissues from IBD patients and mice compared with their control counterparts, respectively. We also noted attenuation of colitis through gene transfer of Gstt1 to DSS-treated mice via the interleukin-22 (IL-22) pathway. GSTT1 was differently regulated by pathogens and host immune responses. Down-regulation of GSTT1 reduced innate defence responses and goblet cell differentiation. The GSTT1 mutation in intestinal epithelial cells as well as IBD patients diminished its dimerisation, which was connected to insufficient phosphorylation of signal transducer and activator of transcription 3 and p38/mitogen-activated protein kinase by their common activator, IL-22.

Conclusion

GSTT1 ameliorated IL-22 in colitis in a dependent manner and contributed as a modulator of goblet cells through sensing pathogens and host immune responses. Its mutations are linked to chronic intestinal inflammation due to its insufficient dimerisation. Our results provide new insights into GSTT1 mutations and their functional consequences in IBDs.
P109 Construction of a suite of computable biological network models focused on inflammatory bowel disease
Authors: Ruiz Castro P A , Yepiskoposyan H , Szostak J , Talikka M , Hoeng J
Published: January 2020

Background

Inﬂammatory bowel diseases (IBDs) are chronic relapsing inflammatory disorders that result from an inappropriate inflammatory response to the enteric microbiota in a genetically susceptible host. Because the molecular mechanisms of IBD have been the subject of intensive exploration, we assembled the available information into a suite of comprehensive causal biological network models, which offer a better visualisation and understanding of the processes underlying IBD.

Methods

Biological expression language (BEL), which represents biological findings in a computable form was used for scientific text curation. The curated BEL statements were compiled using the OpenBEL framework 3.0.0. Cytoscape was used to visualise and analyse network properties. The network perturbation amplitude methodology was used to score the network models with transcriptomic data from public data repositories.

Results

The IBD network model suite consists of four independent models that represent signalling pathways contributing to biological processes involved in IBD. In the ‘wound healing’ model, fibroblast growth factor and thymosin β-4-associated signalling pathways emerged as the main routes leading to epithelial cell proliferation and thus to wound repair. Phosphoinositide 3-kinases and carcinoembryonic antigen-related cell adhesion molecule-associated pathways were identified in the ‘bacterial colonisation’ model as the primary pathways modulating bacterial adhesion and internalisation. In the ‘immunity’ model, nuclear factor-κB and myeloid differentiation primary response 88 emerged as the main contributors to immune responses. In the ‘epithelial barrier defence’ model, tumour necrosis factor- and interleukin 1-associated signalling cascades were the main routes leading to tight junction disruption and thereby, to increased permeability in the intestinal epithelium. The scoring of publicly available transcriptomic data sets onto these network models demonstrates that the IBD models capture the perturbation in each dataset accurately.

Conclusion

This work is a continuation of our approach using computational biological network models and mathematical algorithms in order to interpret high-throughput molecular datasets. The IBD network model suite can provide better mechanistic insights of the transcriptional changes in IBD and constitutes a valuable tool in personalised medicine to further understand molecular heterogeneity and individual drug responses in IBD.
P118 A comprehensive evaluation of mucosal redness in patients with ulcerative colitis by linked colour imaging
Authors: Uchiyama K , Kubota M , Azuma Y , Yasuda R , Shun T , Takagi T , Naito Y , Yoshito I
Published: January 2020

Background

Mucosal healing is important for the patients of ulcerative colitis (UC) to avoid clinical relapse and developing colitic cancer. Though Mayo endoscopic subscore (MES) has been widely used to evaluate mucosal healing of UC patients, it is not enough to predict relapse. We have reported the new endoscopic evaluation by linked colour imaging (LCI) that enhances mucosal redness and can predict relapse with more precision compared with MES1). However, the diagnosis in both MES and LCI depends on the local lesion and it has not been established the comprehensive evaluation because mucosal redness is not clearly recognised by white light image. In the present study, we examined the comprehensive evaluation of mucosal redness in the patients of UC by LCI and investigate the relation with long-term prognosis.

Methods

All examinations were carried out with an EG-L590WR endoscope and a LASEREO endoscopic system (FUJIFILM Co., Tokyo, Japan) including 47 UC patients (pan colitis type) with clinically remission (Under 4 of Lichtiger CAI score). Each part of the large intestine (ascending colon, transverse colon, descending colon, sigmoid colon and rectum) was observed with LCI and WLI (white light image), and the area of redness (regardless of strength) was evaluated. The score was marked 0, 1, 2 and 3, in case of the area of redness is 0%, <50%, 50% or higher and 100%, respectively. The score of each part was totalled (total redness score), and the relapse rate for 1 year after the endoscopy was investigated. Relapse of ulcerative colitis was defined as the need for more aggressive medication for ulcerative colitis due to aggravation or clinical symptoms, or aggravation of endoscopic findings.

Results

The relapse ratio was 19.1% (9/47 cases). The average of total redness score by LCI was 4.02 ± 2.25 and total redness score by WLI was 3.11 ± 2.5. The average of total redness score by LCI in the patients with no relapse group was 3.94 ± 2.21, on the other hand, with relapse group was 4.33 ± 2.23 (p = 0.0354). However, total redness score measured by WLI showed no statistical difference between no relapse group and relapse (p = 0.278).

Conclusion

A comprehensive evaluation of mucosal redness using LCI is useful approach to predict relapse for UC patients with clinical remission.
P143 Gastrointestinal ultrasound is an accurate marker for endoscopic activity in Crohn’s disease
Authors: Sævik F , Gilja O H , Nylund K
Published: January 2020

Background

Treatment goals for Crohn’s disease (CD) have changed from symptom control to objective endpoints, preferably endoscopic remission. However, as the relative invasiveness of ileocolonoscopy limits repeated examinations, a surrogate marker of endoscopic remission is needed. Gastrointestinal ultrasound (GIUS) is accurate in detecting CD, and we aimed to explore its ability to distinguish between patients with active disease from patients in remission.

Methods

One hundred and forty-five CD patients scheduled for ileocolonoscopy were prospectively included. The endoscopic disease activity was quantified using the Simple Endoscopic Score for Crohn’s disease (SES-CD), and endoscopic remission was strictly defined as SES-CD=0. Ultrasound remission was defined as wall thickness <3 mm (<4 mm in the rectum). Additionally, SES-CD was compared with colour Doppler, Harvey Bradshaw’s index (HBI), C-reactive protein (CRP) and calprotectin. Twenty-three patients were examined by two investigators for interobserver assessment.

Results

102 had active disease and 43 patients were in remission. GIUS yielded a sensitivity of 92.2% and specificity of 86% for wall thickness and sensitivity 66.7% and specificity 97.7% for colour Doppler. For HBI sensitivity was 34.3% and specificity 88.4%, CRP sensitivity 35.7% and specificity 82.9% and calprotectin sensitivity 55.9 % and specificity 82.1%. The interobserver analysis revealed excellent agreement (k=0.90).

Conclusion

GIUS has a high sensitivity for detecting endoscopic activity, but poorer specificity. In a hospital cohort of patients with Crohn’s disease, the number of invasive procedures could be reduced by reserving ileocolonoscopy for patients with a normal ultrasound for identification of patients in remission.
P149 Ulcerative colitis patients with high calprotectin levels should undergo endoscopy within 7 days for therapeutic decision
Authors: Kim J O , Jeon S R , Park H , Kim H G , Ko B M , Park S
Published: January 2020

Background

Fecal calprotectin (FC) has considered as a useful surrogate marker to predict which patients with ulcerative colitis (UC) are in endoscopic activity. FC has to be collected at the time of endoscopy for more accurate correlation between FC and endoscopic disease activity. In real practice, however, both tests cannot be easy to perform at the same time. Therefore, the aim of this study was to evaluate the optimal time interval for the correlation between FC and endoscopic disease activity in UC patients.

Methods

We analysed retrospectively 103 cases (79 patients) that was performed FC measurement and endoscopy within 3 months. FC quantitative tests was defined as normal (<100 μg/g), mild (100–200, 100–250 or 100–300 μg/g), and moderate to severe activity (>200, > 250, or > 300 μg/g). Endoscopic activity was graded using the Mayo endoscopic subscore (MES). After assessing concordance between FC level and MES, we use the youden index method to estimate the optimal time interval between both tests using the receiver operator curves (ROCs).

Results

Among 79 UC patients, 64.5% (51/79) were male. The mean FC level was 673.6 ± 1054 μg/g. The mean interval between FC measurement and endoscopy was 13.8 ± 22.7 days. FC levels and MES were positively correlated (r = 0.473, p < 0.001). Using a ROC curve with a cut off value of FC 200 μg/g, the optimal cut-off of the time interval for separation of non-correlation and correlation between FC level and MES was 7 days with a sensitivity of 74.4% and a specificity of 50.0% (AUC 0.6032; 95% CI 0.4779–0.6896). Similarly, using ROC curves with a cut off value of FC 250 or 300 μg/g as a standard for dividing mild and moderate, the optimal cut-off of the time interval were all 5.5 days (FC 250, sensitivity 71.7%, specificity 49.1, AUC 0.5862, 95% CI 0.4728–0.6884; FC 300, sensitivity 69.6%, specificity 47.4, AUC 0.5549, 95% CI 0.4668–0.6513).

Conclusion

FC level within 7 days could reflect endoscopic disease activity in patients with UC. In patients with high-level FC more than 200 μg/g, endoscopic evaluation for therapeutic decision making should be performed within a maximum of 7 days.
P150 Risk of hepatitis flare in patients with previous hepatitis B virus exposure amongst inflammatory bowel disease patients: results from a territory-wide Hong Kong IBD Registry study
Authors: Mak J W Y , Yip T C F , Lam H M , Cheng T Y , Wong S H , Chan F K L , Ng S C , Wong V W S , Wong G L H
Published: January 2020

Background

Biological therapies, thiopurines and steroid are commonly used in the treatment of inflammatory bowel disease (IBD) and may cause hepatitis B virus (HBV) reactivation. However, their exact risk of hepatitis B flare in patients with previous HBV exposure is poorly defined. We aim to study the risk of hepatitis flare in IBD patients with previous HBV exposure.

Methods

Patients were identified from a territory-wide Hong Kong IBD Registry. IBD patients who were negative for HBsAg and received biological therapies or thiopurines or steroids from 1 January 2000 to 30 June 2019 were included. Patients who were positive for total antibody to hepatitis B core antigen (anti-HBc) and/or hepatitis B surface antigen (anti-HBs) were defined to have previous HBV exposure. Primary endpoint was development of hepatitis flare (alanine Aminotransferase [ALT) >80U/L).

Results

Total 369 patients fulfilled the inclusion criteria and were classified into three groups: anti-HBs positive only (n = 246); anti-HBs and anti-HBc positive (n = 78) and anti-HBc positive only (n = 45). Median follow-up duration was 60 months (Interquartile range: 32.7–60 months). Seventy-six IBD patients (20.6%) developed hepatitis flare. Cumulative incidence of hepatitis flare were 13.2%, 18.3% and 22% at 12 months, 36 months and 60 months respectively. Use of thiopurine [adjusted hazard ratio (aHR) 2.56; 95% Confidence Interval (CI) 1.54 – 4.26, p < 0.001]and ever exposure to steroid [aHR 2.73; 95% CI 1.30–5.72; p = 0.008] were risk factors for hepatitis flare after adjustment of baseline ALT level. The use of biological therapy was not associated with risk of hepatitis flare [aHR 1.79; 95% CI 0.79–3.99; p = 0.14]. Ever exposure to steroid was associated with increased risk of hepatitis flare irrespective of the peak dose (<20mg prednisolone daily, 20-40mg daily or >40mg daily) [aHR: 2.34–4.18]. Fifteen patients (4.1%) developed severe icteric hepatitis flare (ALT > 120U/L and bilirubin >38 mmol/L). Cumulative incidence of severe icteric hepatitis flare were 2.7%, 7.2% and 8.4% at 12 months, 36 months and 60 months respectively.

Conclusion

Amongst IBD patients with previous HBV exposure who were treated with biological therapy, thiopurines or steroid, 20.6% developed hepatitis flare. The use of thiopurine and ever exposure to steroid were risk factors for hepatitis flare. The use of biological therapy was not associated with risk of hepatitis flare.