Human skin-resident CD8+ T cells require RUNX2 and RUNX3 for induction of cytotoxicity and expression of the integrin CD49a.

The integrin CD49a marks highly cytotoxic epidermal-tissue-resident memory (TRM) cells, but their differentiation from circulating populations remains poorly defined. We demonstrate enrichment of RUNT family transcription-factor-binding motifs in human epidermal CD8+CD103+CD49a+ TRM cells, paralleled by high RUNX2 and RUNX3 protein expression. Sequencing of paired skin and blood samples revealed clonal overlap between epidermal CD8+CD103+CD49a+ TRM cells and circulating memory CD8+CD45RA-CD62L+ T cells. In vitro stimulation of circulating CD8+CD45RA-CD62L+ T cells with IL-15 and TGF-ß induced CD49a expression and cytotoxic transcriptional profiles in a RUNX2- and RUNX3-dependent manner. We therefore identified a reservoir of circulating cells with cytotoxic TRM potential. In melanoma patients, high RUNX2, but not RUNX3, transcription correlated with a cytotoxic CD8+CD103+CD49a+ TRM cell signature and improved patient survival. Together, our results indicate that combined RUNX2 and RUNX3 activity promotes the differentiation of cytotoxic CD8+CD103+CD49a+ TRM cells, providing immunosurveillance of infected and malignant cells.

Does cardiovascular risk matter in IBD patients?

Cardiovascular and thromboembolic risks are increasing in the population as a whole and therefore also in inflammatory bowel disease (IBD) patients. Obesity is a worldwide challenge also affecting the IBD population, and a causal association with Crohn's disease may exist. IBD itself, particularly when active, is also associated with a significant risk of thromboembolic and cardiovascular events such as myocardial infarction and stroke. Cardiovascular risk is also a significant consideration when using Janus kinase (JAK) inhibitors and sphingosine 1 phosphate (S1P) receptor modulators to treat IBD. JAK inhibitors - such as tofacitinib - are associated with several cardiovascular and venous thromboembolic risks, including hypertension and alterations in lipid profiles - specifically, increased LDL cholesterol and triglycerides - which may contribute to atherosclerosis and cardiovascular disease. S1P receptor modulators pose a slightly different set of cardiovascular risks. Initially, these drugs can cause transient bradycardia and atrioventricular (AV) block, leading to bradycardia. Moreover, they may induce QT interval prolongation, which increases the risk of life-threatening arrhythmias such as torsades de pointes. Some patients may also experience hypertension as a side effect. In this context, IBD healthcare providers need to be alert to the assessment of cardiovascular risk - particularly as cardiovascular events appear to be confined to specific patient groups with pre-existing risk factors. In addition, the potential for S1P modulator drug interactions requires a higher level of vigilance in patients with polypharmacy compared to biologics. Cardiovascular risk is not static, and updated assessment will need to become part of the routine in many IBD units.

Tumour necrosis factor inhibitors in Crohn's disease and the effect on surgery rates.

AIM: Surgery is an important therapeutic option for Crohn's disease. The need for first bowel surgery seems to have decreased with the introduction of tumour necrosis factor inhibitors (TNFi; adalimumab or infliximab). However, the impact of TNFi on the need for intestinal surgery in Crohn's disease patients irrespective of prior bowel resection is not known. The aim of this work is to compare the incidence of bowel surgery in Crohn's disease patients who remain on TNFi treatment versus those who discontinue it. METHOD: We performed a nationwide register-based observational cohort study in Sweden of all incident and prevalent cases of Crohn's disease who started first-line TNFi treatment between 2006 and 2017. Patients were categorized according to TNFi treatment retention less than or beyond 1 year. The study cohort was evaluated with regard to incidence of bowel surgery from 12 months after the first ever TNFi dispensation. RESULTS: We identified 5003 Crohn's disease patients with TNFi exposure: 3748 surgery naïve and 1255 with bowel surgery prior to TNFi initiation. Of these patients, 7% (n = 353) were subjected to abdominal surgery during the first 12 months after the start of TNFi and were subsequently excluded from the main analysis. A majority (62%) continued TNFi for 12 months or more. Treatment with TNFi for less than 12 months was associated with a significantly higher surgery rate compared with patients who continued on TNFi for 12 months or more (hazard ratio 1.26, 95% CI 1.09-1.46; p = 0.002). CONCLUSION: Treatment with TNFi for less than 12 months was associated with a higher risk of bowel surgery in Crohn's disease patients compared with those who continued TNFi for 12 months or more.

Older age is a risk factor for inadequate energy intake during acute, severe IBD and is associated with shorter time to relapse.

BACKGROUND: Effects of nutritional intake on inflammatory bowel disease (IBD) flare resolution are unknown. We hypothesised that nutritional factors during hospitalisation for acute severe IBD are associated with risk of subsequent relapse. We also studied risk factors for inadequate energy intake. METHODS: Patients admitted to the Karolinska Hospital Gastroenterology ward with IBD flare during 2015-2016 were retrospectively identified. In total, 91 patients were included. Data on nutrition, disease factors, inflammatory markers, and daily energy requirement were extracted. Requirement of new systemic steroid prescription, intensification of biological therapy, readmission, surgery, and calprotectin level were individually used as proxies for disease relapse. Follow-up was one year after discharge. Adjustments for age and sex were made where appropriate. RESULTS: Overall, 19%, 31%, and 45% of patients had days with energy intake <30, <50, and <70% of calculated requirement. Older age was associated with a higher number of days with energy intake <30, <50, and <70% of calculated requirement (regression coefficient 0.03, 0.04, 0.06 respectively, p = .012, .017, .008). The number of days with energy intake <30 and <70% of the calculated requirement and the length of the hospitalisation were associated with shorter time to new steroid prescription (hazard ratio 1.3, 1.1, 1.04 respectively, p = .016, .034, .011). CRP and calprotectin were not associated with relapse. CONCLUSION: Older age is a predictor of inadequate energy intake during hospitalisation for acute severe IBD. Inadequate energy intake adjusted for age and sex during IBD flare was better predictor of time to the next steroid-requiring relapse than inflammatory markers.

Towards improved control of inflammatory bowel disease.

Inflammatory bowel disease (IBD) is characterized by activation of both the innate and adaptive immune system in genetically susceptible individuals, resulting in chronic intestinal inflammation. The triggers that initiate and perpetuate this continuous inflammation are the subject of much speculation and research, although the central role of the intestinal microbiota is recognized, and is even a target for treatment in some circumstances. The mainstay of modern IBD treatment is suppression of the immune response towards as yet unspecified antigens, and conventional therapy includes corticosteroids, 5-aminosalicylic acid (5-ASA), thiopurines and methotrexate. Reducing activity of specific mediators has proven efficacious, including adhesion molecules, such as the gut-homing integrin α4 ß7 expressed on the surface of circulating immune cells, and cytokines, such as tumour necrosis factor α (TNF-α). This has been achieved using biologic agents including monoclonal antibodies. Recent discoveries in immunology and neuroscience have revealed that signals in the peripheral nervous system regulate inflammation, including levels of TNF-α. The understanding of the mechanisms of the neuro-immune communication involved in inflammation control in the gut is evolving, but is as yet incomplete. Clinical studies using implanted vagus nerve stimulators for treatment of IBD show encouraging results. Accordingly, the neural reflex control of inflammation is emerging as a potential therapeutic target in treatment of IBD. Here, we review current therapeutic options and neural reflex control of gut immunity in the context of intestinal inflammation.

Faecal biomarkers for diagnosis and prediction of disease course in treatment-naïve patients with IBD.

BACKGROUND: Faecal biomarkers can be used to assess inflammatory bowel disease (IBD). AIM: To explore the performance of some promising biomarkers in diagnosing and predicting disease course in IBD. METHODS: We included 65 patients with treatment-naïve, new-onset Crohn's disease (CD), 90 with ulcerative colitis (UC), 67 symptomatic controls (SC) and 41 healthy controls (HC) in this prospective observational study. We analysed faecal samples for calprotectin (FC), myeloperoxidase (MPO), human neutrophil lipocalin (HNL), eosinophil cationic protein ECP and eosinophil-derived neurotoxin (EDN) and compared markers among groups. We assessed the diagnostic capability of biomarkers with receiver operating characteristic curves. Clinical disease course was determined for each patient with IBD and analysed the association with biomarkers by logistic regression. RESULTS: All markers were elevated at inclusion in patients with IBD compared with HC (p < 0.001) and SC (p < 0.001). FC (AUC 0.85, 95% CI: 0.79-0.89) and MPO (AUC 0.85, 95% CI: 0.80-0.89) showed the highest diagnostic accuracy in distinguishing IBD from SC. The diagnostic ability of biomarkers differed between IBD subtypes with the highest performance for FC and MPO in CD. The diagnostic accuracy was further improved by combining FC and MPO (p = 0.02). Levels of FC, MPO and HNL at inclusion were predictive of an aggressive disease course with MPO showing the strongest association (p = 0.006). CONCLUSIONS: This study provides new insight into the diagnostic and prognostic capability of neutrophil and eosinophil biomarkers in IBD and suggests that MPO, alone or in combination with FC, may add to the diagnostic power of faecal biomarkers.

Identification and validation of a blood- based diagnostic lipidomic signature of pediatric inflammatory bowel disease.

Improved biomarkers are needed for pediatric inflammatory bowel disease. Here we identify a diagnostic lipidomic signature for pediatric inflammatory bowel disease by analyzing blood samples from a discovery cohort of incident treatment-naïve pediatric patients and validating findings in an independent inception cohort. The lipidomic signature comprising of only lactosyl ceramide (d18:1/16:0) and phosphatidylcholine (18:0p/22:6) improves the diagnostic prediction compared with high-sensitivity C-reactive protein. Adding high-sensitivity C-reactive protein to the signature does not improve its performance. In patients providing a stool sample, the diagnostic performance of the lipidomic signature and fecal calprotectin, a marker of gastrointestinal inflammation, does not substantially differ. Upon investigation in a third pediatric cohort, the findings of increased lactosyl ceramide (d18:1/16:0) and decreased phosphatidylcholine (18:0p/22:6) absolute concentrations are confirmed. Translation of the lipidomic signature into a scalable diagnostic blood test for pediatric inflammatory bowel disease has the potential to support clinical decision making.

Scalable in situ single-cell profiling by electrophoretic capture of mRNA using EEL FISH.

Methods to spatially profile the transcriptome are dominated by a trade-off between resolution and throughput. Here we develop a method named Enhanced ELectric Fluorescence in situ Hybridization (EEL FISH) that can rapidly process large tissue samples without compromising spatial resolution. By electrophoretically transferring RNA from a tissue section onto a capture surface, EEL speeds up data acquisition by reducing the amount of imaging needed, while ensuring that RNA molecules move straight down toward the surface, preserving single-cell resolution. We apply EEL on eight entire sagittal sections of the mouse brain and measure the expression patterns of up to 440 genes to reveal complex tissue organization. Moreover, EEL can be used to study challenging human samples by removing autofluorescent lipofuscin, enabling the spatial transcriptome of the human visual cortex to be visualized. We provide full hardware specifications, all protocols and complete software for instrument control, image processing, data analysis and visualization.

Fecal Biomarkers of Neutrophil and Eosinophil Origin Reflect the Response to Biological Therapy and Corticosteroids in Patients With Inflammatory Bowel Disease.

INTRODUCTION: Fecal calprotectin (FC) is a noninvasive tool for examining response to biologics in inflammatory bowel disease (IBD), but its performance in relation to other novel fecal markers of various cellular origins is unknown. METHODS: We performed a prospective multicenter cohort study and included patients with active IBD who provided a fecal sample at initiation of biological therapy. Levels of FC, myeloperoxidase (MPO), human neutrophil lipocalin (HNL), and eosinophil-derived neurotoxin (EDN) were analyzed and related to clinical remission status at 3 months. Changes in levels of markers at 3 months were calculated, and the impact of concomitant use of corticosteroids at baseline was estimated. RESULTS: In patients achieving clinical remission (n = 27), a decrease in levels of FC ( P = 0.005), MPO ( P < 0.001), HNL ( P < 0.001), and EDN ( P < 0.001) was observed, whereas no significant decrease was seen in patients not achieving remission (n = 39). There was a significant difference in the change in the level of MPO ( P = 0.01) and HNL ( P = 0.02) between patients achieving clinical remission and those who did not, but changes in FC and EDN could not differentiate between these groups. Patients with concomitant systemic corticosteroids at inclusion had lower levels of HNL ( P = 0.01) and EDN ( P < 0.001) at baseline, compared with patients without corticosteroids. DISCUSSION: Fecal MPO, HNL, and EDN are all promising biomarkers for assessing the treatment outcome of biologics in patients with IBD. Fecal levels of EDN and HNL are significantly affected by corticosteroids indicating a greater sensitivity to the effects of corticosteroids compared with levels of FC and MPO.

A Core Outcome Set for inflammatory bowel diseases: development and recommendations for implementation in clinical practice through an international multi-stakeholder consensus process.

BACKGROUND AND AIMS: Standardising health outcome measurements supports delivery of care, enables data-driven learning systems, and secondary data use for research. As part of the Health Outcomes Observatory initiative and building on existing knowledge, a core outcome set (COS) for inflammatory bowel diseases (IBD) was defined through an international modified Delphi method. METHODS: Stakeholders rated 90 variables on a 9-point importance scale twice, allowing score modification based on feedback displayed per stakeholder group. Two consecutive consensus meetings were held to discuss results and formulate recommendations for measurement in clinical practice. Variables scoring 7 or higher by ≥80% of the participants, or based on consensus meeting agreement, were included in the final set. RESULTS: In total, 136 stakeholders (45 IBD patients (advocates), 74 healthcare professionals/researchers, 13 industry representatives and 4 regulators), from 20 different countries participated. The final set includes 18 case-mix variables, 3 biomarkers (haemoglobin to detect anaemia, C-reactive protein and faecal calprotectin to detect inflammation) for completeness and 28 outcomes (including 16 patient-reported outcomes (PROs) and 1 patient-reported experience). The PRO-2 and IBD-Control questionnaires were recommended to collect disease-specific PROs at every contact with an IBD practitioner, and the Subjective Health Experience model questionnaire, PROMIS Global Health and Self-Efficacy short form to collect generic PROs annually. CONCLUSIONS: A COS for IBD, including a recommendation for use in clinical practice, was defined. Implementation of this set will start in Vienna, Berlin, Barcelona, Leuven and Rotterdam, empowering patients to better manage their care. Additional centres will follow worldwide.

Randomised, double-blind, placebo-controlled trial of fructo-oligosaccharides in active Crohn's disease.

INTRODUCTION: The commensal intestinal microbiota drive the inflammation associated with Crohn's disease. However, bacteria such as bifidobacteria and Faecalibacterium prausnitzii appear to be immunoregulatory. In healthy subjects the intestinal microbiota are influenced by prebiotic carbohydrates such as fructo-oligosaccharides (FOS). Preliminary data suggest that FOS increase faecal bifidobacteria, induce immunoregulatory dendritic cell (DC) responses and reduce disease activity in patients with Crohn's disease. AIMS AND METHODS: To assess the impact of FOS in patients with active Crohn's disease using an adequately powered randomised double-blind placebo-controlled trial with predefined clinical, microbiological and immunological end points. Patients with active Crohn's disease were randomised to 15 g/day FOS or non-prebiotic placebo for 4 weeks. The primary end point was clinical response at week 4 (fall in Crohn's Disease Activity Index of ≥ 70 points) in the intention-to-treat (ITT) population. RESULTS: 103 patients were randomised to receive FOS (n = 54) or placebo (n = 49). More patients receiving FOS (14 (26%) vs 4 (8%); p = 0.018) withdrew before the 4-week end point. There was no significant difference in the number of patients achieving a clinical response between the FOS and placebo groups in the ITT analysis (12 (22%) vs 19 (39%), p = 0.067). Patients receiving FOS had reduced proportions of interleukin (IL)-6-positive lamina propria DC and increased DC staining of IL-10 (p < 0.05) but no change in IL-12p40 production. There were no significant differences in the faecal concentration of bifidobacteria and F prausnitzii between the groups at baseline or after the 4-week intervention. CONCLUSION: An adequately powered placebo-controlled trial of FOS showed no clinical benefit in patients with active Crohn's disease, despite impacting on DC function. ISRCTN50422530.

Mechanisms of mucosal healing: treating inflammatory bowel disease without immunosuppression?

Almost all currently available treatments for inflammatory bowel disease (IBD) act by inhibiting inflammation, often blocking specific inflammatory molecules. However, given the infectious and neoplastic disease burden associated with chronic immunosuppressive therapy, the goal of attaining mucosal healing without immunosuppression is attractive. The absence of treatments that directly promote mucosal healing and regeneration in IBD could be linked to the lack of understanding of the underlying pathways. The range of potential strategies to achieve mucosal healing is diverse. However, the targeting of regenerative mechanisms has not yet been achieved for IBD. Stem cells provide hope as a regenerative treatment and are used in limited clinical situations. Growth factors are available for the treatment of short bowel syndrome but have not yet been applied in IBD. The therapeutic application of organoid culture and stem cell therapy to generate new intestinal tissue could provide a novel mechanism to restore barrier function in IBD. Furthermore, blocking key effectors of barrier dysfunction (such as MLCK or damage-associated molecular pattern molecules) has shown promise in experimental IBD. Here, we review the diversity of molecular targets available to directly promote mucosal healing, experimental models to identify new potential pathways and some of the anticipated potential therapies for IBD.

Ustekinumab treatment in ulcerative colitis: Real-world data from the Swedish inflammatory bowel disease quality register.

BACKGROUND: Real-world data on clinical outcomes of ustekinumab in ulcerative colitis are lacking. OBJECTIVE: To assess short- and long-term clinical outcomes of ustekinumab in ulcerative colitis. METHODS: Adult ulcerative colitis patients without previous colectomy starting ustekinumab treatment up until 11 December 2020 were identified through the Swedish Inflammatory Bowel Disease Register (SWIBREG). Prospectively recorded data were extracted from the SWIBREG. The primary outcome was persistence to ustekinumab 16 weeks after treatment initiation. Secondary outcomes included drug persistence beyond week 16, clinical remission (defined as a patient-reported Mayo rectal bleeding subscore = 0 and stool frequency subscore ≤1), biochemical remission (defined as faecal-calprotectin <250 µg/g) and changes in health-related quality of life (HRQoL), as measured by the Short Health Scale (SHS). Logistic regression was used to identify potential predictors of ustekinumab persistence at 16 weeks. RESULTS: Of the 133 patients with ulcerative colitis, only three were naïve to biologics and tofacitinib. The persistence rates of ustekinumab were 115/133 (86%) at 16 weeks and 89/133 (67%) at last follow-up, that is, after a median follow-up of 32 (interquartile range 19-56) weeks. The clinical remission rates were 17% at 16 weeks and 32% at the last follow-up. The corresponding rates for biochemical remission were 14% and 23%. The median faecal-calprotectin concentration decreased from 740 µg/g at baseline to 98 µg/g at the last follow-up (p < 0.01, n = 37). Improvement was seen in each dimension of the SHS between baseline and last follow-up (p < 0.01 for each dimension, n = 46). Male sex was associated with ustekinumab persistence at 16 weeks (adjusted odds ratio = 4.00, 95% confidence interval: 1.35-11.83). CONCLUSION: In this nationwide real-world cohort of ulcerative colitis patients with prior drug failures, including other biologics and tofacitinib, ustekinumab was associated with high drug persistence rates and improvements in clinical, biochemical and HRQoL measures.

Immunological Networks Defining the Heterogeneity of Inflammatory Bowel Diseases.

Current practice in IBD is to classify patients based on clinical signs and symptoms and provide treatments accordingly. However, the response of IBD patients to available treatments is highly variable, highlighting clinically significant heterogeneity among patients. Thus, more accurate patient stratification is urgently needed to more effectively target therapeutic interventions to specific patients. Here we review the degree of heterogeneity in IBD, discussing how the microbiota, genetics, and immune system may contribute to the variation among patients. We highlight how molecular heterogeneity may relate to clinical phenotype, but in other situations may be independent of clinical phenotype, encouraging future studies to fill the gaps. Finally, we discuss novel stratification methodologies as a foundation for precision medicine, in particular a novel stratification strategy based on conserved genes across species. All of these dimensions of heterogeneity have potential to provide strategies for patient stratification and move IBD practice towards personalised medicine.

Results of the Seventh Scientific Workshop of ECCO: Precision Medicine in IBD-Prediction and Prevention of Inflammatory Bowel Disease.

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.

Smokers with active Crohn's disease have a clinically relevant dysbiosis of the gastrointestinal microbiota.

BACKGROUND: Patients with Crohn's disease (CD) have an intestinal dysbiosis with components of the microbiota exerting differential immune effects. Smoking is associated with an increased incidence of CD, more frequent relapse, and greater burden of surgery. This study aimed to investigate the association between smoking and the intestinal microbiota in patients with active CD. METHODS: Patients with active CD (n = 103) and healthy controls (n = 66) were recruited and demographic and clinical data recorded including current smoking behavior. Fecal samples were collected and analyzed by fluorescent in situ hybridization using probes targeting 16S rRNA of bacteria previously shown to be altered in active CD (bifidobacteria, bacteroides, Clostridium coccoides-Eubacterium rectale, Escherichia coli, and Faecalibacterium prausnitzii). RESULTS: In total, 29/101 (29%) patients with CD and 8/58 (14%) controls were current smokers (P = 0.032). Following multivariate analysis, smoking was found to have a significant and independent effect on the microbiota of patients with CD, with higher Bacteroides-Prevotella in smokers (38.4%) compared with nonsmokers (28.1%) (F((1,93)) = 12.6, P = 0.001). Healthy controls who smoked also had higher Bacteroides-Prevotella (34.8%) than nonsmokers (24.1%) (F((1,55)) = 4.5, P = 0.038). In the pooled multivariate analysis, patients with CD had higher bifidobacteria (F((1,156)) = 30.5, P < 0.001), higher Bacteroides-Prevotella (F((1,156)) = 6.5, P = 0.012), and lower F. prausnitzii (F((1,156)) = 3.8, P = 0.052) compared with healthy controls. CONCLUSIONS: Smokers have luminal microbiota that consist of significantly higher bacteroides. Investigation of whether this is one mechanism through which the negative effects of smoking on CD are mediated is warranted.

Probiotic and prebiotic use in patients with inflammatory bowel disease: a case-control study.

BACKGROUND: The use of complementary and alternative medicine in inflammatory bowel disease (IBD) has been extensively studied. However, the use of probiotics and prebiotics is poorly documented, despite evidence of efficacy of particular probiotic strains in specific forms of IBD. METHODS: A case-control study comprising interviewer-administered questionnaires was conducted in IBD patients and healthy controls. Data regarding use and knowledge of probiotics and prebiotics, demographic, and clinical information were collected. RESULTS: In total, 334 participants (234 IBD, 100 controls) were interviewed. Significantly more IBD patients than controls had ever used probiotics to manage their health (Crohn's disease [CD] 43%, ulcerative colitis [UC] 51%, controls 21%, P < 0.001). Prebiotic use was negligible. On logistic regression analysis, having UC (odds ratio [OR] 4.30, 95% confidence interval [CI] 2.27-8.12) or CD (OR 3.05, 95% CI 1.66-5.60) were the strongest predictors of probiotic use. Within IBD patients the strongest predictor of probiotic use was current steroid use (OR 2.4, 95% CI 1.11-5.18). IBD patients had greater probiotic knowledge scores than controls (P = 0.003), although 20% of IBD probiotic users could not provide a definition of a probiotic. Less than half of IBD probiotic users discussed probiotic use with healthcare professionals, with commercial advertising being the primary source of information. CONCLUSIONS: Patients with IBD use probiotics to manage their health but frequently choose strains without evidence of efficacy in IBD. Patients rely on nonclinical sources of information and often do not disclose probiotic use to healthcare professionals. Conventional healthcare providers should inquire about probiotic use among their patients and offer evidence-based advice.