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ObjectiveInflammatory bowel disease (IBD) is a multifactorial condition driven by genetic and environmental risk factors. A genetic variation in the protein tyrosine phosphatase non-receptor type 22 (PTPN22) gene has been associated with autoimmune disorders while protecting from the IBD subtype Crohn’s disease. Mice expressing the murine orthologous PTPN22-R619W variant are protected from intestinal inflammation in the model of acute dextran sodium sulfate (DSS)-induced colitis. We previously identified food-grade titanium dioxide (TiO2, E171) as a neglected IBD risk factor. Here, we investigate the interplay of the PTPN22 variant and TiO2-mediated effects during IBD pathogenesis.DesignAcute DSS colitis was induced in wild-type and PTPN22 variant mice (PTPN22-R619W) and animals were treated with TiO2nanoparticles during colitis induction. Disease-triggering mechanisms were investigated using bulk and single-cell RNA sequencing.ResultsIn mice, administration of TiO2nanoparticles abrogated the protective effect of the variant, rendering PTPN22-R619W mice susceptible to DSS colitis. In early disease, cytotoxic CD8+T-cells were found to be reduced in the lamina propria of PTPN22-R619W mice, an effect reversed by TiO2administration. Normalisation of T-cell populations correlated with increasedIfngexpression and, at a later stage of disease, the promoted prevalence of proinflammatory macrophages that triggered severe intestinal inflammation.ConclusionOur findings indicate that the consumption of TiO2nanoparticles might have adverse effects on the gastrointestinal health of individuals carrying the PTPN22 variant. This demonstrates that environmental factors interact with genetic risk variants and can reverse a protective mechanism into a disease-promoting effect.

ZusammenfassungEssstörungen sind potenziell lebensbedrohliche Erkrankungen, die mit schweren psychischen und somatischen Komorbiditäten einhergehen. Man geht davon aus, dass die Anzahl an Patienten im Nachgang der Covid-Pandemie stark ansteigen wird.Hauptsächlich 4 Essstörungen werden im Diagnostic and Statistical Manual of Mental Disorders 5 (DSM-5) und der International Classification of Diseases 11 (ICD-11) erwähnt: Anorexia nervosa (AN), Bulimia nervosa (BN), Binge eating disorder (BED) und Avoidant restrictive food intake disorder (ARFID). Viele traditionelle Annahmen bei Essstörungen sind aufgrund neuer Forschungsresultate im Wandel begriffen. Der/die Gastroenterologe/in ist normalerweise nicht die erste Anlaufstelle für Patienten/-innen mit Essstörungen. Er spielt jedoch eine zentrale Rolle, insbesondere wenn es um das Management von gastroenterologischen Komplikationen geht.In dieser Übersicht soll der Fokus vor allem auf relevante gastroenterologische Aspekte und weniger auf die psychiatrische/psychosomatische Behandlung gelegt werden. Die Grundlagen der wichtigsten Essstörungen werden wiederholt, Möglichkeiten der Erkennung und wichtige gastroenterologische Komplikationen genannt. Die Adipositas, die oft mit Essstörungen einhergeht, ist nicht Gegenstand dieser Übersicht.

Background: Anemia is the most frequent extraintestinal manifestation of inflammatory bowel disease (IBD) and is associated with the risk of Crohn’s disease. Anemia significantly impairs quality of life, increases hospitalization rates, and increases medical care costs of IBD patients. Iron deficiency is the most frequent cause of anemia in IBD; however, the mechanisms involved are still poorly understood. Here, we investigated the role of the IBD risk gene, protein tyrosine phosphatase non-receptor type 2 ( PTPN2), in regulating iron homeostasis. Methods: Constitutive Ptpn2 wild type (WT), heterozygous (Het), and knockout (KO) 3-week-old mice were analyzed for serum iron content, complete blood count parameters, and intestinal and extraintestinal non-heme iron. Protein and RNA from duodenal epithelial cells (DECs) were assayed by western blotting and qPCR. Localization of the brush border ferrous iron transporter, DMT1, and the ferrous iron absorption driver, NHE3, in duodenal tissue was determined by immunohistochemistry (IHC). Results: Ptpn2-KO mice had reduced i) serum iron ( p=0.0007; n=10); ii) serum iron carrier transferrin saturation ( p=0.0077; n=8); iii) hemoglobin ( p=0.0002; n=5); iv) hematocrit ( p=0.0023; n=5); v) intestinal non-heme iron: duodenum ( p=0.0128; n=10) and jejunum ( p=0.0006; n=8); and vi) extraintestinal tissue non-heme iron: liver ( p=0.0014; n=10), spleen ( p=0.04; n=10), kidney ( p=0.0004; n=7), and gastrocnemius muscle ( p=0.0436; n=9) vs. Ptpn2-WT and Het mice. This indicated that loss of Ptpn2 causes characteristics of anemia including decreased serum iron and tissue iron storage and impaired intestinal iron homeostasis. DEC gene expression of the intracellular iron storage molecule ferritin ( Fth1) was reduced ( p=0.048; n=4) while the basolateral cellular iron importer transferrin receptor 1 ( Tfrc1) was significantly increased ( p=0.0048; n=5) in Ptpn2-KO mice. Reduced FTH1 protein expression ( p=0.007; n=12) and increased TFRC1 protein expression ( p=0.0021; n=8) in DECs of Ptpn2-KO mice was confirmed by western blot, indicating cellular iron deficiency. DMT1 (n=6) and NHE3 (n=8) protein expression in DECs was unaltered, whereas IHC showed reduced apical membrane DMT1 and NHE3 in the duodenal epithelium of Ptpn2-KO mice (n=6), suggesting a possible mechanism of impaired intestinal non-heme iron uptake. Conclusions: Loss of Ptpn2 in mice causes features of anemia including iron deficiency associated with mislocalization of DMT1 and reduced apical membrane expression of NHE3. These findings identify a critical role for PTPN2 in regulating systemic iron homeostasis. This is the full abstract presented at the American Physiology Summit 2023 meeting and is only available in HTML format. There are no additional versions or additional content available for this abstract. Physiology was not involved in the peer review process.

Background and Aims Exacerbated immune activation, intestinal dysbiosis and a disrupted intestinal barrier are common features among inflammatory bowel disease [IBD] patients. The polyamine spermidine, which is naturally present in all living organisms, is an integral component of the human diet, and exerts beneficial effects in human diseases. Here, we investigated whether spermidine treatment ameliorates intestinal inflammation and offers therapeutic potential for IBD treatment. Methods We assessed the effect of oral spermidine administration on colitis severity in the T cell transfer colitis model in Rag2−/− mice by endoscopy, histology and analysis of markers of molecular inflammation. The effects on the intestinal microbiome were determined by 16S rDNA sequencing of mouse faeces. The impact on intestinal barrier integrity was evaluated in co-cultures of patient-derived macrophages with intestinal epithelial cells. Results Spermidine administration protected mice from intestinal inflammation in a dose-dependent manner. While T helper cell subsets remained unaffected, spermidine promoted anti-inflammatory macrophages and prevented the microbiome shift from Firmicutes and Bacteroides to Proteobacteria, maintaining a healthy gut microbiome. Consistent with spermidine as a potent activator of the anti-inflammatory molecule protein tyrosine phosphatase non-receptor type 2 [PTPN2], its colitis-protective effect was dependent on PTPN2 in intestinal epithelial cells and in myeloid cells. The loss of PTPN2 in epithelial and myeloid cells, but not in T cells, abrogated the barrier-protective, anti-inflammatory effect of spermidine and prevented the anti-inflammatory polarization of macrophages. Conclusion Spermidine reduces intestinal inflammation by promoting anti-inflammatory macrophages, maintaining a healthy microbiome and preserving epithelial barrier integrity in a PTPN2-dependent manner.

Many diseases that affect modern humans fall in the category of complex diseases, thus called because they result from a combination of multiple aetiological and pathogenic factors. Regardless of the organ or system affected, complex diseases present major challenges in diagnosis, classification, and management. Current forms of therapy are usually applied in an indiscriminate fashion based on clinical information, but even the most advanced drugs only benefit a limited number of patients and to a variable and unpredictable degree. This ‘one measure does not fit all’ situation has spurred the notion that therapy for complex disease should be tailored to individual patients or groups of patients, giving rise to the notion of ‘precision medicine’ [PM]. Inflammatory bowel disease [IBD] is a prototypical complex disease where the need for PM has become increasingly clear. This prompted the European Crohn’s and Colitis Organisation to focus the Seventh Scientific Workshop on this emerging theme. The articles in this special issue of the Journal address the various complementary aspects of PM in IBD, including what PM is; why it is needed and how it can be used; how PM can contribute to prediction and prevention of IBD; how IBD PM can aid in prognosis and improve response to therapy; and the challenges and future directions of PM in IBD. This first article of this series is structured on three simple concepts [what, why, and how] and addresses the definition of PM, discusses the rationale for the need of PM in IBD, and outlines the methodology required to implement PM in IBD in a correct and clinically meaningful way.

Enteral feed bezoars are difficult to treat and can lead to serious adverse events. There is no standardized treatment approach and various strategies have been suggested. We herein describe three cases of successful dissolutions of feed bezoars consisting of Promote® Fibre Plus with sodium bicarbonate 8.4% in critically ill patients. To provide the rationale for this approach, the effect of sodium bicarbonate 8.4% on enteral feed concretions was studied in vitro. First, Promote® Fibres Plus was incubated with hydrochloric acid with gradually decreasing pH values to establish a pH at which the solution solidifies. The resulting enteral feed concretion was exposed to sodium bicarbonate 8.4% and Coca Cola®. All patients were successfully treated with sodium bicarbonate 8.4% without the need of lengthy or repeat endoscopies. In vitro, Promote® Fibres Plus solidifies when acidified below a pH of 4.6. The resulting enteral feed concretions dissolved when exposed to sodium bicarbonate 8.4%. Incubation with Coca Cola® had no effect. We provide evidence that enteral feed bezoars consisting of Promote® Fibres Plus can be efficiently and safely treated with sodium bicarbonate 8.4% offering a new approach for daily patient care.

Background and aims A single nucleotide polymorphism in protein tyrosine phosphatase non-receptor type 22 [PTPN22] has been associated with the onset of autoimmune disorders, but protects from Crohn’s disease. PTPN22 deficiency in mice promotes intestinal inflammation by modulating lymphocyte function. However, the impact of myeloid PTPN22 in colitis development remains unclear. The aim of this study was to investigate the role of PTPN2 in the IL-10 and the T cell transfer colitis models. Methods PTPN22-deficient mice were crossed with IL-10-/- and RAG2-/- mice. Naïve T cells were injected in RAG-/- mice to induce T-cell transfer colitis. Spontaneous colitis in IL-10-/- mice was monitored for up to 200 days. Results Here, we demonstrate that PTPN22 in non-lymphoid immune cells is required to protect against T cell transfer-mediated and IL-10 knock-out colitis. Analysis of the intestinal immune landscape demonstrated a marked reduction of granulocyte influx into the inflamed colon in PTPN22-deficient mice. On a molecular level, granulocytes were not only reduced by numbers, but also revealed a defective function. In particular, granulocyte activation and granulocyte-mediated bacteria killing was impaired upon loss of PTPN22, resulting in elevated bacterial burden and translocation beyond the intestinal epithelial barrier in PTPN22-deficient mice. Consistently, antibiotic-induced depletion of bacteria reverted the increased colitis susceptibility in PTPN22-deficient mice, whereas granulocyte depletion induced acolitis phenotype in wild-type mice similar to that observed in PTPN22-deficient mice. Conclusions In conclusion, our data demonstrate that PTPN22 is essential for adequate granulocyte activation and antimicrobial defence to protect the inflamed intestine from bacterial invasion and exacerbated colitis.

Background Vedolizumab is a widely used and safe therapy in inflammatory bowel disease, particularly in ulcerative colitis (UC), making it a promising candidate for enhanced efficacy by combining it with additional immunomodulatory medications. In this study, we studied the impact of vedolizumab monotreatment vs vedolizumab coadministration with other immunomodulatory drugs on intestinal inflammation and intestinal immune cells in vivo. Methods Colon tissue from human patients with UC with active disease or in remission with or without vedolizumab treatment was stained by immunohistochemistry. We reconstituted NOD-SCID-SGM3 mice with human CD34+ cells and treated them with dextran sodium sulfate to induce acute colitis. Mice were treated with vedolizumab alone, or in combination with tacrolimus, ozanimid, or tofacitinib. Results Vedolizumab reduced the number of CD3+ T cells and CD68+ monocytes/macrophages in the colon of patients with UC with active disease. Vedolizumab moderately decreased immune cell numbers in acute dextran sodium sulfate–induced colitis. The combination of vedolizumab with tacrolimus further reduced the number of infiltrating CD3+ T cells and CD68+ monocytes/macrophages and was superior in ameliorating intestinal inflammation when compared to vedolizumab monotreatment. In contrast, cotreatment using vedolizumab with ozanimod or tofacitinib had no additive effect. Conclusions Our data show that vedolizumab reduces the number of innate and adaptive immune cells in the mucosa of patients with UC. Further, the combination of vedolizumab with tacrolimus was more efficient to reduce immune cell numbers and to increase therapeutic efficacy than vedolizumab monotreatment. This finding indicates that combination treatment using these two drugs may be beneficial for patients who do not respond to vedolizumab monotherapy.

BACKGROUND Perianal fistulae strongly impact on quality of life of affected patients. AIM To challenge and novel minimally invasive treatment options are needed. METHODS Patients with Crohn’s disease (CD) in remission and patients without inflammatory bowel disease (non-IBD patients) were treated with fistulodesis, a method including curettage of fistula tract, flushing with acetylcysteine and doxycycline, Z-suture of the inner fistula opening, fibrin glue instillation, and Z-suture of the outer fistula opening followed by post-operative antibiotic prophylaxis with ciprofloxacin and metronidazole for two weeks. Patients with a maximum of 2 fistula openings and no clinical or endosonographic signs of a complicated fistula were included. The primary end point was fistula healing, defined as macroscopic and clinical fistula closure and lack of patient reported fistula symptoms at 24 wk. RESULTS Fistulodesis was performed in 17 non-IBD and 3 CD patients, with a total of 22 fistulae. After 24 wk, all fistulae were healed in 4 non-IBD and 2 CD patients (overall 30%) and fistula remained closed until the end of follow-up at 10-25 mo. In a secondary per-fistula analysis, 7 out of 22 fistulae (32%) were closed. Perianal disease activity index (PDAI) improved in patients with fistula healing. Low PDAI was associated with favorable outcome (P = 0.0013). No serious adverse events were observed. CONCLUSION Fistulodesis is feasible and safe for perianal fistula closure. Overall success rates is at 30% comparable to other similar techniques. A trend for better outcomes in patients with low PDAI needs to be confirmed.

Background and Aims Ulcerative colitis [UC] patients have a greater risk of developing colorectal cancer through inflammation-dysplasia-carcinoma sequence of transformation. The histopathological diagnosis of dysplasia is therefore of critical clinical relevance, but dysplasia may be difficult to distinguish from inflammatory changes. Methods A proteomic pilot study on five UC colorectal dysplastic patients highlighted proteins differentially distributed between paired dysplastic, inflammatory, and normal tissues. The best candidate marker was selected and immunohistochemistry confirmation was performed on azoxymethane/dextran sulphate sodium [AOM/DSS] mouse model lesions, 37 UC-dysplasias, 14 UC-cancers, 23 cases of long-standing UC, 35 sporadic conventional adenomas, 57 sporadic serrated lesions, and 82 sporadic colorectal cancers. Results Differential proteomics found 11 proteins significantly more abundant in dysplasia compared with inflammation, including Solute carrier family 12 member 2 [SLC12A2] which was confidently identified with eight specific peptides and was below the limit of quantitation in both inflammatory and normal colon. SLC12A2 immunohistochemical analysis confirmed the discrimination of preneoplastic and neoplastic lesions from inflammatory lesions in mice, in UC, and in sporadic contexts. A specific SLC12A2 staining pattern termed ‘loss of gradient’ reached 89% sensitivity, 95% specificity, and 92% accuracy for UC-dysplasia diagnosis together with an inter-observer agreement of 95.24% [multirater κ free of 0.90; 95% CI: 0.78 - 1.00]. Such discrimination could not be obtained by Ki67 staining. This specific pattern was also associated with sporadic colorectal adenomas and cancers. Conclusions We found a specific SLC12A2 immunohistochemical staining pattern in precancerous and cancerous colonic UC lesions which could be helpful for diagnosing dysplasia and cancer in UC and non-UC patients.

IntroductionThe human microbiota, the community of micro-organisms in different cavities, has been increasingly linked with inflammatory and neoplastic diseases. While investigation into the gut microbiome has been robust, the urinary microbiome has only recently been described. Investigation into the relationship between bladder cancer (BC) and the bladder and the intestinal microbiome may elucidate a pathophysiological relationship between the two. The bladder or the intestinal microbiome or the interplay between both may also act as a non-invasive biomarker for tumour behaviour. While these associations have not yet been fully investigated, urologists have been manipulating the bladder microbiome for treatment of BC for more than 40 years, treating high grade non-muscle invasive BC (NMIBC) with intravesical BCG immunotherapy. Neither the association between the microbiome sampled directly from bladder tissue and the response to BCG-therapy nor the association between response to BCG-therapy with the faecal microbiome has been studied until now. A prognostic tool prior to initiation of BCG-therapy is still needed.Methods and analysisIn patients with NMIBC bladder samples will be collected during surgery (bladder microbiome assessment), faecal samples (microbiome assessment), instrumented urine and blood samples (biobank) will also be taken. We will analyse the microbial community by 16S rDNA gene amplicon sequencing. The difference in alpha diversity (diversity of species within each sample) and beta diversity (change in species diversity) between BCG-candidates will be assessed. Subgroup analysis will be performed which will lead to the development of a clinical prediction model estimating risk of BCG-response.Ethics and disseminationThe study has been approved by the Cantonal Ethics Committee Zurich (2021-01783) and it is being conducted in accordance with the Declaration of Helsinki and Good Clinical Practice. Study results will be disseminated through peer-reviewed journals and national and international scientific conferences.Trial registration numberNCT05204199.

Intestinal stem cells (ISC) are characterized by their ability to continuously self-renew and differentiate into various functionally distinct intestinal epithelial cell types. Impaired stem cell proliferation and differentiation can cause severe dysfunction of the gastrointestinal tract and lead to the development of several clinical disorders. Animal mouse models provide a valuable platform to study ISC function, disease mechanisms, and the intestinal epithelium's regenerative capacity upon tissue damage. However, advanced in vitro systems that are more relevant to human physiology are needed to understand better the diverse disease-triggering factors and the heterogeneity in clinical manifestations. Intestinal biopsies from patients might serve as potent starting material for such "gut-in-a-dish" approaches. While many promising tools for intestinal tissue processing, in vitro expansion, and downstream analysis have been developed in recent years, a comprehensive guide with recommendations to successfully launch or improve intestinal stem cell culture is missing. In this review, we present a selection of currently established methods, highlight recent publications and discuss the potential and limitations of those methodological approaches to facilitate and support the future design of novel and more personalized therapeutic options.

Protein tyrosine phosphatase nonreceptor type 2 (PTPN2) has emerged as a promising cancer immunotherapy target. Previously, we reported on the functional role of PTPN2 in the pathogenesis of colorectal carcinoma (CRC). We demonstrated increased PTPN2 phosphatase activity correlates with disease progression and decreased immune responses in tumor tissues, while loss of PTPN2 in T-cells or in dendritic cells (DCs) reduces tumor burden in several CRC models and potentiates anti-PD1 efficacy (Katkeviciute et al., 2021). Others reported that loss of PTPN2 in tumor cells sensitizes to immune-mediated tumor killing (Manguso et al., 2017; Goh et al., 2022). Thus, PTPN2 was proposed as a critical node to modulate anti-tumor immunity, and PTPN2 inhibition is expected to enhance anti-tumor immunity by sensitizing tumor cells and by activating immune cells. Recently, also the closely related phosphatase PTPN1 (PTP1B) was demonstrated to restrain T-cell mediated tumor killing (Wiede et al., 2022). Inhibition of Protein Tyrosine Phosphatases has historically been a demanding area for drug discovery. However, both allosteric PTP inhibitors (eg targeting SHP2/PTPN11) and catalytic-site inhibitors (targeting PTPN2/N1) have recently progressed to clinical studies. We now identified a chemical series of novel dual PTPN2/N1 inhibitors. These inhibitors bind to the catalytic site of PTPN2, as confirmed by crystallography. The best molecules of the series are low nM inhibitors of PTPN2 and PTPN1 enzymes with excellent selectivity across other phosphatases. As an immediate consequence of PTPN2/N1 inhibition, these compounds augment phosphorylation of STAT1 and/or STAT5 isoforms in myeloid and T-cell lines, and in primary T-cells, macrophages and DCs. This results in immune-cell activation as evidenced by increased production of effector cytokines (e.g. IFNγ), immune-activation, levels of cytotoxicity markers in T-cells (e.g. granzyme B) as well as upregulation of antigen presentation and co-stimulatory markers in macrophages and DCs. Furthermore, inhibition of PTPN2/N1 sensitizes murine and human cancer cell lines to IFNγ, and enhances immune-mediated tumor killing in co-culture assays in vitro. In vivo evaluation of selected examples is in progress and results will be presented at the conference. Our data indicate that inhibition of PTPN2/N1 phosphatase activity is a powerful pharmacologic strategy to promote anti-tumor immunity, with strong potential to be exploited for cancer immunotherapy both as a single agent treatment in anti-PD1 refractory cancers, and in combination with anti-PD1 therapy. Citation Format: Kalliopi Pervolaraki, Egle Katkeviciute, Dominique Lambin, Sandro Boland, Amuri Kilonda, Vincent Pericolle, Marnik Nijs, Wanda Haeck, Kristine Metzger, Hugo Klaassen, Arnaud Marchand, Patrick Chaltin, Matthias Versele, Marianne Spalinger, Michael Scharl. Discovery of potent and selective inhibitors of the protein tyrosine phosphatases PTPN2 and PTPN1 to trigger anti-tumor immunity through sensitization of tumor cells and activation of immune cells. [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2023; Part 1 (Regular and Invited Abstracts); 2023 Apr 14-19; Orlando, FL. Philadelphia (PA): AACR; Cancer Res 2023;83(7_Suppl):Abstract nr 4038.

Inflammatory bowel disease has a high incidence and prevalence especially in young individuals in their reproductive years. Trying to conceive and being pregnant is an emotional period for those involved. In the majority of patients suffering from inflammatory bowel disease, maintenance therapy is required during pregnancy to control the disease, and disease control might necessitate introduction of new drugs during a vulnerable period. Therefore, the management of patients with a wish to conceive and during pregnancy requires specialized counselling and appropriate management including a multidisciplinary approach and close involvement of the prospective parents under a shared decision-making model. This updated consensus paper addresses these issues and is aimed to optimize pre-conceptional, pregnancy and post pregnancy counselling, including the monitoring and therapeutic management of patients with IBD patients with a wish to conceive. ispartof: JOURNAL OF CROHNS & COLITIS vol:17 issue:1 pages:1-27 ispartof: location:England status: published

ObjectivesAlterations in the intestinal microbiota are linked with a wide range of autoimmune and inflammatory conditions, including inflammatory bowel diseases (IBD), where pathobionts penetrate the intestinal barrier and promote inflammatory reactions. In patients with IBD, the ability of intestinal macrophages to efficiently clear invading pathogens is compromised resulting in increased bacterial translocation and excessive immune reactions. Here, we investigated how an IBD-associated loss-of-function variant in the protein tyrosine phosphatase non-receptor type 2 (PTPN2) gene, or loss of PTPN2 expression affected the ability of macrophages to respond to invading bacteria.DesignIBD patient-derived macrophages with wild-type (WT) PTPN2 or carrying the IBD-associated PTPN2 SNP, peritoneal macrophages from WT and constitutive PTPN2-knockout mice, as well as mice specifically lacking PTPN2 in macrophages were infected with non-invasive K12 Escherichia coli, the human adherent-invasive E. coli (AIEC) LF82, or a novel mouse AIEC (mAIEC) strain.ResultsLoss of PTPN2 severely compromises the ability of macrophages to clear invading bacteria. Specifically, loss of functional PTPN2 promoted pathobiont invasion/uptake into macrophages and intracellular survival/proliferation by three distinct mechanisms: Increased bacterial uptake was mediated by enhanced expression of carcinoembryonic antigen cellular adhesion molecule (CEACAM)1 and CEACAM6 in PTPN2-deficient cells, while reduced bacterial clearance resulted from defects in autophagy coupled with compromised lysosomal acidification. In vivo, mice lacking PTPN2 in macrophages were more susceptible to mAIEC infection and mAIEC-induced disease.ConclusionsOur findings reveal a tripartite regulatory mechanism by which PTPN2 preserves macrophage antibacterial function, thus crucially contributing to host defence against invading bacteria.

Plastic pollution is a major global challenge of our times, baring a potential threat for the environment and the human health. The increasing abundance of nanoplastic (NP) and microplastic (MP) particles in the human diet might negatively affect human health since they - particularly in patients suffering from inflammatory bowel disease (IBD) - might surpass the intestinal barrier. To investigate whether ingested plastic particles cross the intestinal epithelium and promote bowel inflammation, mice were supplemented with NP or MP polystyrene (PS) particles for 24 or 12 weeks before inducing acute or chronic dextran sodium sulfate (DSS) colitis with continuous plastic administration. Although ingested PS particles accumulated in the small intestine and organs distant from the gastrointestinal tract, PS ingestion did not affect intestinal health nor did it promote colitis severity. Although the lack of colitis-promoting effects of small PS particles might be a relief for IBD patients, potential accumulative effects of ingested plastic particles on the gastrointestinal health cannot be excluded.

Application of dextran sodium sulfate (DSS) is often used to induce experimental colitis. Current state of the art is to refrain from the use of analgesics due to their possible interaction with the model. However, the use of analgesics would be beneficial to reduce the overall constraint imposed on the animals. Here, we analyzed the effect of the analgesics Dafalgan (paracetamol), Tramal (tramadol) and Novalgin (metamizole) on DSS-induced colitis. To study the effect of those analgesics in colitis mouse models, acute and chronic colitis was induced in female C57BL6 mice by DSS administration in the drinking water. Analgesics were added to the drinking water on days four to seven (acute colitis) or on days six to nine of each DSS cycle (chronic colitis). Tramadol and paracetamol had minor effects on colitis severity. Tramadol reduced water uptake and activity levels slightly, while mice receiving paracetamol presented with a better overall appearance. Metamizole, however, significantly reduced water uptake, resulting in pronounced weight loss. In conclusion, our experiments show that tramadol and paracetamol are viable options for the use in DSS-induced colitis models. However, paracetamol seems to be slightly more favorable since it promoted the overall wellbeing of the animals upon DSS administration without interfering with typical readouts of colitis severity.

Crohn’s disease (CD) is a major form of inflammatory bowel disease characterized by transmural inflammation along the alimentary tract. Changes in the microbial composition and reduction in species diversity are recognized as pivotal hallmarks in disease dynamics, challenging the gut barrier function and shaping a pathological immune response in genetically influenced subjects. The purpose of this review is to delve into the modification of the gut microbiota cluster network during CD progression and to discuss how this shift compromises the gut barrier integrity, granting the translocation of microbes and their products. We then complete the scope of the review by retracing gut microbiota dysbiosis interactions with the main pathophysiologic factors of CD, starting from the host’s genetic background to the immune inflammatory and fibrotic processes, providing a standpoint on the lifestyle/exogenous factors and the potential benefits of targeting a specific gut microbiota.

Background and Aims: The majority of patients treated with anti-tumor necrosis factor (TNF) therapy develop anti-drug antibodies (ADAs), which might result in loss of treatment efficacy. Strict guidelines on measuring trough levels (TLs) and ADA in clinical routine do not exist. To provide real-world data, we took advantage of our tertiary inflammatory bowel disease (IBD) center patient cohort and determined indicators for therapeutic drug monitoring (TDM) and actual consequences in patient care. Methods: We retrospectively collected clinical data of 104 IBD patients treated with infliximab or adalimumab in our IBD clinic. Patients with TL and ADA measurements between June 2015 and February 2018 were included. Results: The main reason for determining TL was increased clinical disease. Subtherapeutic TLs were found in 33 patients, therapeutic TLs in 33 patients, and supratherapeutic TLs in 38 patients. Adjustments in anti-TNF therapy occurred more frequently (p = 0.01) in patients with subtherapeutic TL (24 of 33 patients; 73%) as compared to patients with therapeutic and supratherapeutic TLs (26 of 71 patients; 37%). No correlation could be found between TL and disease activity (p = 0.16). Presence of ADA was found in 16 patients, correlated with the development of infusion reactions (OR: 10.6, RR: 5.4, CI: 2.9–38.6), and was associated with subtherapeutic TL in 15 patients (93.8%). Treatment adaptations were based on TL and/or ADA presence in 36 of 63 patients. Conclusions: TDM showed significant treatment adaptations in patients with subtherapeutic TL. Conversely, in patients with therapeutic and supratherapeutic TLs, reasons for adaptations were based on considerations other than TL, such as clinical disease activity. Further studies should focus on decision-making in patients presenting with supratherapeutic TL in remission.

Fistula treatment represents a major unmet medical need in the therapy of Crohn’s disease (CD). Current medical therapies, such as anti-TNF antibody treatments, are often insufficient and do not achieve permanent fistula closure. Previously published data point toward a critical role for metalloproteinase-9 (MMP-9)/gelatinase B in fistula pathogenesis. The aim of this project was to investigate in detail MMP-9 expression in different fistula types and to confirm that MMP-9 is a potential target for fistula therapy in CD patients. Immunohistochemistry for total and active MMP-9, Cytokeratin 8 (CK-8) and co-staining of active MMP-9/CK-8 was performed in specimen derived from perianal fistulas, entero-enteric fistulas and fistulas from patients not responding to anti-TNF therapy. In addition, fistulas from the xenograft mouse model (anti-TNF treated or untreated) were analyzed. Total and active MMP-9 protein was detectable in cells lining the tracts of perianal and entero-enteric fistulas. Of note, total and active MMP-9 was also expressed in fistulas of CD patients non-responding to anti-TNF treatment. Interestingly, we detected considerable co-staining of active MMP-9 and CK-8 in particular in cells lining the fistula tract and in transitional cells around the fistulas. Furthermore, total and active MMP-9 are detectable in both anti-TNF treated and untreated xenograft fistulas. Taken together, our data suggest that MMP-9 is involved in fistula pathogenesis in CD patients, in fistulas of different origins and particularly in patients non-responding to anti-TNF therapy. Our xenograft fistula model is suitable for in vivo studies investigating a possible therapeutic role for MMP-9 targeting as fistula therapy.

ispartof: JOURNAL OF CROHNS & COLITIS vol:15 issue:9 pages:1407-1409 ispartof: location:England status: published

Das „severe acute respiratory syndrome coronavirus 2“ (SARS-CoV-2) verursacht die Coronaviruserkrankung (COVID-19), die aktuell pandemisch ist und sich mit einer infektiösen Pneumonie manifestiert. Neben den typischen Symptomen, wie Fieber, Husten und Dyspnoe, entwickeln einige Patienten auch gastrointestinale und hepatische Manifestationen, die sich meist als Diarrhö, Nausea, Erbrechen und Abdominalschmerzen bemerkbar machen. Von hepatischer Seite können erhöhte Leberenzyme beobachtet werden. SARS-CoV‑2 kann den Gastrointestinaltrakt via den Rezeptor „angiotensin converting enzyme 2“ infizieren, der auf den Enterozyten des Ileums und Kolons exprimiert wird. Virale RNA wurde im Stuhl vom COVID-19-Patienten isoliert, was die Möglichkeit offenlässt, dass SARS-CoV‑2 neben der Tröpfcheninfektion auch mittels fäkal-oraler Transmission übertragen werden kann. Der Einfluss von SARS-CoV‑2 auf zugrunde liegende Erkrankungen des Gastrointestinaltrakts und des hepatobiliären Systems wird aktuell ausführlich untersucht. Dieser Artikel soll einen kurzen Überblick verschaffen bezüglich gastroenterologischer und hepatologischer Manifestationen von COVID-19 sowie des Einflusses von COVID-19 auf zugrunde liegende, chronische gastroenterologische Erkrankungen.

Background/Aims: The hepatitis C virus nonstructural 3/4A protease has been shown to cleave protein tyrosine phosphatase nonreceptor type 2 (PTPN2, also known as T cell protein tyrosine phosphatase), thereby inducing a shift from a Th1 toward a nonantiviral Th2 immunity. Ribavirin therapy reverses these effects and supports direct-acting antiviral (DAA) therapy as an immunomodulatory compound and ultimately improves the response to DAA therapy. Here we aimed to assess whether intrahepatic levels of PTPN2 might be used as a clinical prognostic marker for the response to DAA therapy. Methods: Liver biopsies from hepatitis C virus-infected patients with and without cirrhosis were immunohistochemically stained for PTPN2 and scored for staining intensity as well as percentage of hepatocytes positive for nuclear PTPN2 localization. PTPN2 scores were correlated to sustained virologic response after DAA therapy, viral load, serum levels of alanine aminotransferase, aspartate aminotransferase, gamma-glutamyl transferase (GGT), and the Model for End-Stage Liver Disease (MELD) score at the time of liver biopsy. Results: We did not detect a difference in intrahepatic PTPN2 levels between responders with cirrhosis, responders without cirrhosis, and nonresponders to DAA therapy. There was no correlation between intrahepatic PTPN2 levels and viral load or clinical markers such as liver transaminases, GGT, or the MELD score. Conclusion: Intrahepatic PTPN2 levels assessed via IHC staining do not represent a clinical prognostic marker for the response to DAA therapy.

The purpose of this study was to investigate the impact of obesity on disease activity and disease outcome in patients with inflammatory bowel disease.The impact of obesity on inflammatory bowel disease disease activity and outcome was retrospectively assessed in 3075 patients enrolled in the prospective nation-wide Swiss inflammatory bowel disease cohort between July 2006 and September 2018. Baseline characteristics, disease activity and disease course in 325 obese inflammatory bowel disease patients (body mass index ≥30 kg/mAmong 3075 patients in the prospective Swiss inflammatory bowel disease cohort, 325 patients (10.6%) were obese, namely, 194 Crohn's disease patients, 131 ulcerative colitis, and inflammatory bowel disease-unclassified patients. Disease activity scores were elevated in obese Crohn's disease (Crohn's Disease Activity Index 33 vs 20,Obesity is associated with decreased rates of disease remission and increased risk of complicated disease course in Crohn's disease over a six-year follow-up period. No effects were seen on disease progression and index treatment failure neither in Crohn's disease nor ulcerative colitis.

Proton-sensing ovarian cancer G-protein coupled receptor (OGR1) plays an important role in pH homeostasis. Acidosis occurs at sites of intestinal inflammation and can induce endoplasmic reticulum (ER) stress and the unfolded protein response (UPR), an evolutionary mechanism that enables cells to cope with stressful conditions. ER stress activates autophagy, and both play important roles in gut homeostasis and contribute to the pathogenesis of inflammatory bowel disease (IBD). Using a human intestinal epithelial cell model, we investigated whether our previously observed protective effects of OGR1 deficiency in experimental colitis are associated with a differential regulation of ER stress, the UPR and autophagy. Caco-2 cells stably overexpressing OGR1 were subjected to an acidic pH shift. pH-dependent OGR1-mediated signalling led to a significant upregulation in the ER stress markers, binding immunoglobulin protein (BiP) and phospho-inositol required 1α (IRE1α), which was reversed by a novel OGR1 inhibitor and a c-Jun N-terminal kinase (JNK) inhibitor. Proton-activated OGR1-mediated signalling failed to induce apoptosis, but triggered accumulation of total microtubule-associated protein 1 A/1B-light chain 3, suggesting blockage of late stage autophagy. Our results show novel functions for OGR1 in the regulation of ER stress through the IRE1α-JNK signalling pathway, as well as blockage of autophagosomal degradation. OGR1 inhibition might represent a novel therapeutic approach in IBD.

Fecal microbiota transfer (FMT) is a very efficient approach for the treatment of severe and recurring C. difficile infections. However, the beneficial effect of FMT in other disorders such as ulcerative colitis (UC) or Crohn's disease remains unclear. Furthermore, it is currently unknown how disease-associated genetic variants in donors or recipients influence the effect of FMT. We found that bacteria-transfer from wild-type (WT) donors via cohousing was efficient in inducing recovery from colitis in WT mice, but not in mice deficient in protein-tyrosine phosphatase non-receptor type 22 (PTPN22), a known risk gene for several chronic inflammatory diseases. Also cohousing of PTPN22-deficient mice with diseased WT mice failed to induce faster recovery. Our data indicate that the genetic background of the donor and the recipient influences the outcome of microbiota transfer, and offers a potential explanation why transfer of fecal microbes from some, but not all donors is efficient in UC patients.

Intestinal fibrosis and stenosis are common complications of Crohn’s disease [CD], frequently requiring surgery. Anti-inflammatory strategies can only partially prevent fibrosis; hence, anti-fibrotic therapies remain an unmet clinical need. Oxysterols are oxidised cholesterol derivatives with important roles in various biological processes. The enzyme cholesterol 25-hydroxylase [CH25H] converts cholesterol to 25-hydroxycholesterol [25-HC], which modulates immune responses and oxidative stress. In human intestinal samples from CD patients, we found a strong correlation of CH25H mRNA expression with the expression of fibrosis markers. We demonstrate reduced intestinal fibrosis in mice deficient for the CH25H enzyme, using the sodium dextran sulphate [DSS]-induced chronic colitis model. Additionally, using a heterotopic transplantation model of intestinal fibrosis, we demonstrate reduced collagen deposition and lower concentrations of hydroxyproline in CH25H knockouts. In the heterotopic transplant model, CH25H was expressed in fibroblasts. Taken together, our findings indicate an involvement of oxysterol synthesis in the pathogenesis of intestinal fibrosis.

Inflammatory bowel disease [IBD] is a complex chronic disorder with no clear aetiology and no known cure. Despite recent advances in overall disease management and improved therapeutics, patients with IBD still experience a substantial burden. Furthermore, as the incidence continues to increase in developing areas of the world, it is expected that the burden of IBD to society will increase and exert tremendous pressure on health care systems worldwide. Therefore, new strategies to prevent the global increase of IBD are urgently required. Data are being progressively acquired on the period preceding disease diagnosis, which support the concept that IBD has a preclinical period that may reveal the triggers of disease and may be amenable to early intervention. Having a better knowledge of this preclinical period will increase the potential not only for improved understanding of disease pathogenesis and improved therapeutics, but also for disease prediction and prevention. ispartof: JOURNAL OF CROHNS & COLITIS vol:15 issue:9 pages:1443-1454 ispartof: location:England status: published

Inflammatory bowel disease (IBD) is a multifactorial condition driven by genetic and environmental risk factors. A genetic variation in the protein tyrosine phosphatase non-receptor type 22 (PTPN22) gene has been associated with autoimmune disorders while protecting from the IBD subtype Crohn's disease. Mice expressing the murine orthologous PTPN22-R619W variant are protected from intestinal inflammation in the model of acute dextran sodium sulfate (DSS)-induced colitis. We previously identified food-grade titanium dioxide (TiOAcute DSS colitis was induced in wild-type and PTPN22 variant mice (PTPN22-R619W) and animals were treated with TiOIn mice, administration of TiOOur findings indicate that the consumption of TiO

Asthma is a heterologous disease that is influenced by complex interactions between multiple environmental exposures, metabolism, and host immunoregulatory processes. Specific metabolites are increasingly recognized to influence respiratory inflammation. However, the role of protein‐derived metabolites in regulating inflammatory responses in the lung are poorly described. The aims of the present study were to quantify polyamine levels in bronchoalveolar lavages (BALs) from healthy volunteers and asthma patients, and to evaluate the impact of each polyamine on inflammatory responses using in vitro models and in a house dust mite (HDM)‐induced respiratory allergy model. Spermidine levels were decreased, while cadaverine levels were increased in BALs from asthma patients compared to healthy controls, using Ultra Performance Liquid Chromatography (UPLC). Both spermine and spermidine inhibit lipopolysaccharide (LPS)‐induced cytokine secretion from human peripheral blood mononuclear cells (PBMCs) and dendritic cells (DCs) in vitro. In addition, oral gavage with spermine or spermidine modulate HDM‐induced cell infiltration, cytokine secretion, and epithelial cell tight junction expression in murine models. Spermidine also reduces airway hyper‐responsiveness. These results suggest that modulation of polyamine metabolism, in particular spermidine, is associated with respiratory inflammation and these molecules and pathways should be further explored as biomarkers of disease and potential targets for novel therapies., Spermine and spermidine display anti‐inflammatory effects using in vitro models and protect against house dust mite (HDM) extract‐induced airway inflammation in murine models.

Background and aims: Anxiety and depression are prevalent in patients with inflammatory bowel diseases (IBD), especially during IBD flares. IBD therapies can profoundly affect the mood of patients with IBD. We aimed to determine the long-term impact of anti-tumor necrosis factor (anti-TNF) and immunomodulators (IM) on anxiety and depressive symptoms in IBD patients. Methods: We compared three treatment groups with IM only (group A), anti-TNF ± IM (group B) and no such therapy (group C). Patients completed the hospital anxiety and depression scale (HADS) at 1 year, 3 years, and 5 years after start of treatment. Results: In total, 581 patients with IBD (42.9% Crohn’s disease, 57.1% ulcerative colitis/IBD unclassified) participated in this study. Effects of treatment were analyzed in a mixed effects model, with and without correction for confounders. Compared with group C, group B showed a significant treatment-related improvement in both anxiety and depressive symptoms within the first 2.5 years and also thereafter. Group A showed a significant long-term improvement of anxiety and both short-term and long-term improvement in depressive symptoms. The significance of these results was maintained after correction for confounders, including corticosteroid treatment. Additionally, both groups A and B showed a significant decrease in disease activity in the first 2.5 years after start of treatment and also thereafter. Anti-TNF and IM treatment were associated with a similarly significant decrease in anxiety and depressive symptoms over an observation period of up to 5 years. Conclusion: Besides a clear benefit for disease activity, anti-TNF and IM apparently improve the mood of patients with IBD.

Background and Aims: Local extracellular acidification is associated with several conditions, such as ischemia, cancer, metabolic disease, respiratory diseases, and inflammatory bowel disease (IBD). Several recent studies reported a link between IBD and a family of pH-sensing G protein-coupled receptors. Our previous studies point to an essential role for OGR1 (GPR68) in the modulation of intestinal inflammation and fibrosis. In the current study, we evaluated the effects of a novel OGR1 inhibitor in murine models of colitis. Methods: The effects of a novel small-molecule OGR1 inhibitor were assessed in the acute and chronic dextran sulfate sodium (DSS) murine models of colitis. Macroscopic disease indicators of intestinal inflammation were evaluated, and epithelial damage and immune cell infiltration and proliferation were assessed by immunohistochemistry. Results: The OGR1 inhibitor ameliorated clinical parameters in acute and chronic DSS-induced colitis. In mice treated with the OGR1 inhibitor, endoscopy showed no thickening and normal vascularity, while fibrin was not detected. Histopathological findings revealed a decrease in severity of colonic inflammation in the OGR1 inhibitor group when compared to vehicle-DSS controls. In OGR1 inhibitor-treated mice, staining for the macrophage marker F4/80 and cellular proliferation marker Ki-67 revealed a reduction of infiltrating macrophages and slightly enhanced cell proliferation, respectively. This was accompanied by a reduction in pro-inflammatory cytokines, TNF and IL-6, and the fibrosis marker TGF-β1. Conclusion: This is the first report providing evidence that a pharmacological inhibition of OGR1 has a therapeutic effect in murine colitis models. Our data suggest that targeting proton-sensing OGR1 using specific small-molecule inhibitors may be a novel therapeutic approach for the treatment of IBD.

Protein tyrosine phosphatase nonreceptor type 2 (PTPN2) plays a critical role in the pathogenesis of inflammatory bowel diseases (IBD). Mice lacking PTPN2 in dendritic cells (DCs) develop skin and liver inflammation by the age of 22 weeks due to a generalized loss of tolerance leading to uncontrolled immune responses. The effect of DC-specific PTPN2 loss on intestinal health, however, is unknown. The aim of this study was to investigate the DC-specific role of PTPN2 in the intestine during colitis development. PTPN2fl/flxCD11cCre mice were subjected to acute and chronic DSS colitis as well as T cell transfer colitis. Lamina propria immune cell populations were analyzed using flow cytometry. DC-specific PTPN2 deletion promoted infiltration of B and T lymphocytes, macrophages, and DCs into the lamina propria of unchallenged mice and elevated Th1 abundance during acute DSS colitis, suggesting an important role for PTPN2 in DCs in maintaining intestinal immune cell homeostasis. Surprisingly, those immune cell alterations did not translate into increased colitis susceptibility in acute and chronic DSS-induced colitis or T cell transfer colitis models. However, macrophage depletion by clodronate caused enhanced colitis severity in mice with a DC-specific loss of PTPN2. Loss of PTPN2 in DCs affects the composition of lamina propria lymphocytes, resulting in increased infiltration of innate and adaptive immune cells. However, this did not result in an elevated colitis phenotype, likely because increased infiltration of macrophages in the intestine upon loss of PTPN2 loss in DCs can compensate for the inflammatory effect of PTPN2-deficient DCs.

INTRODUCTION Despite enormous efforts during the past decades, pancreatic adenocarcinoma (PAC) remains one of the most deleterious cancer entities. A useful biomarker for early detection or prognosis of PAC does not yet exist. The goal of our study was the characterization of β6-integrin (ITGB6) as a novel serum tumor marker for refined diagnosis and prognosis of PAC. Serum ITGB6 levels were analyzed in 3 independent PAC cohorts consisting of retrospectively and prospectively collected serum and/or (metastatic) PAC tissue specimens. METHODS Using 2 independent cohorts, we measured serum ITGB6 concentrations in 10 chronic pancreatitis patients, 10 controls, as well as in 27 (cohort 1) and 24 (cohort 2) patients with PAC, respectively. In these patients, we investigated whether ITGB6 serum levels correlate with known clinical and prognostic markers for PAC and whether they might differ between patients with PAC or benign inflammatory diseases of the pancreas. RESULTS We found that elevated serum ITGB6 levels (≥0.100 ng/mL) in patients suffering from metastasizing PAC presented an unfavorable prognostic outcome. By correlating the ITGB6 tissue expression in primary and metastatic PAC with clinical parameters, we found that positive ITGB6 expression in the tumor tissue is linked to increased serum ITGB6 levels in nonmetastatic PAC and correlates with carbohydrate antigen 19-9 and clinical outcome. DISCUSSION Our findings suggest that ITGB6 might serve as a novel serum biomarker for early diagnosis and prognosis of PAC. Given the limited specificity and sensitivity of currently used carbohydrate antigen 19-9-based assays, ITGB6 may have the potential to improve the diagnostic accuracy for PAC.

Colorectal cancers (CRCs) remain one of the most common and challenging neoplasia in the Western world. The response rate of immunotherapeutic treatment approaches in a subset of advanced CRCs is remarkable and has sustainably changed treatment regimens. Unfortunately, currently available immunotherapeutics only displayed significant antitumoral activity – in terms of progression free survival (PFS) and objective response rate (ORR) – in microsatellite instability-high (MSI-H)/DNA mismatch repair deficient (dMMR) CRCs. Subsequently, these remarkable results had led to the US Food and Drug Administration’s approval of both immune checkpoint inhibitors (ICIs) pembrolizumab and nivolumab in the treatment of advanced MSI-H/dMMR CRCs. However, in microsatellite stable (MSS)/DNA mismatch repair proficient (pMMR) CRCs, ICIs have clearly failed to meet their expectations and are therefore not considered effective. As the vast majority of CRCs display a molecular MSS/pMMR profile, current treatment approaches endeavor to improve tumor immunogenicity that consecutively leads to increased proinflammatory cytokine levels as well as tumor infiltrating T-cells, which in turn may be targeted by various immunotherapeutic agents. Therefore, ongoing studies are investigating novel synergistic therapy modalities and approaches to overcome a “cold” to “hot” tumor conversion in MSS/pMMR CRCs. In this review, we summarize the efficacy and possible immune-related adverse events as well as novel therapeutic approaches of ICIs in the treatment of MSI-H/dMMR and MSS/pMMR CRCs.