bluuebunny/crossref_metadata_2025_split huggingface dataset:
P006 MiR-192 is associated with stricturing phenotype in Crohn’s disease
Authors: Cristina T , Mateescu B , Mitroi A , Cozaru G , Brinzan C , State M , Dumitru A , Rafti R , Dina E , Alexandrescu L , Dumitru E 
Published: January 2022

Abstract

Background
MicroRNAs (miRNAs) are small, non-coding short (ribonucleic acid) RNAs that have a role in the regulation of genes and protein expression. MiRNAs have altered expression in multiple autoimmune disorders including inflammatory bowel diseases (IBD). This emerging role has led to investigations into miRNA expression profiles in IBD to understand the pathogenesis of these diseases and lead to clinical advances in this area. Due to shared pathways in fibrosis, miRNAs that have a potential role in intestinal fibrosis are worthy of investigation, and miR-192 seems to be associated with fibrosis and strictures in Crohn’s disease (CD). The study aimed to assess the expression levels of tissue and circulating miR-192 in patients with CD.

Methods
The study included 58 patients with CD and 31 subjects as controls for the validation cohort. Demographic and clinical data (including phenotype of the disease), biomarkers: fecal calprotectin (fCal), endoscopy data: Short Endoscopic Score of Crohn’s disease (SES-CD), the expression levels of miR-192 in tissue and serum were assessed (by RT-PCR). Receiver operating characteristic (ROC) analysis was performed to assess the miR-192 expression level as a potential biomarker for stricturing phenotype of CD.

Results
The mean fCal was 345+/- 112 μg/g. The mean SES-CD was 3.4 +/- 1.1. Regarding disease phenotype, 26 (44.8%) had inflammatory phenotype, 32 (55.2%) had stricturing phenotype, and no patient had penetrant phenotype. Regarding location, 20 (34.5%) were ileal, 5 (8.7%) were colonic, and 33 (56.8%) were ileocolic. Strictures were all located in the terminal ileum. The expression level of miR-192 was significantly upregulated in CD tissue samples compared to the control tissue samples only in the patients with stricturing phenotype (8.27 ± 2.87 vs. 4.20 ± 1.94; p &lt; 0.01), whereas in inflammatory phenotype miR-192 was downregulated (-3.47 ± 1.02 vs. - 4.30 ± 0.84; p &lt; 0.01). Similarly, serum miR-31 expression level in CD patients was significantly upregulated than in control serum samples only in the patients with stricturing phenotype (4.07 ± 1.00 vs. 1.55 ± 0.91; p &lt; 0.01), whereas in inflammatory phenotype miR-192 was downregulated (- 0.25 ± 0.79 vs. 0.76 ± 0.83; p &lt; 0.01). There was a strong correlation between tissue and circulating miR-192 with stricturing phenotype (r = 0.89, r = 0.85, p &lt; 0.05). ROC analysis revealed that the expression level of miR-192 could help to discriminate stricturing CD patients from other phenotypes with very good specificity and sensitivity.

Conclusion
MiR-192 is associated with stricturing phenotype in CD and could be a biomarker of intestinal fibrosis. Furthermore, circulating miR-192 could be a non-invasive biomarker of intestinal fibrosis.
P033 Single-cell analysis of gut mucosal- and peripheral blood cells in ulcerative colitis patients undergoing vedolizumab treatment
Authors: Karmi N , Sun S , de Jong S , Bangma A , Teunis J , Paraskevopoulou M , Juarez J , Bleck B , Farahmand S , Weersma R , Bigaeva E , Festen E 
Published: January 2022

Abstract

Background
Vedolizumab (VDZ), a monoclonal antibody that targets α4β7 integrin, was approved to treat moderate-to-severe ulcerative colitis (UC) based on the presumption that it blocks T cell recruitment to the inflamed intestinal mucosa. The clinical evidence suggests that up to 50% of UC patients do not achieve disease remission under VDZ treatment. This study aims to identify changes in cell abundances and molecular pathways associated with VDZ response in UC. To this end, we included anti-tumor necrosis factor (anti-TNF)-naïve and anti-TNF-exposed patients with active UC, and utilized single-cell RNA sequencing (scRNAseq) and high-dimensional flow cytometry (Cytek) to assess the peripheral blood and the gut mucosal compartments.

Methods
Gut mucosal biopsies from inflamed and non-inflamed regions, and peripheral blood mononuclear cells (PBMCs) were obtained from UC patients 2 wks before (t0) and 14 wks after (t4) the start of VDZ administration. Response to treatment was prospectively evaluated based on endoscopic assessment (defined as a decrease in total Mayo score between t0 and t4) and physician global assessment (PGA) that incorporates disease activity score and biochemical measurements.

Results
A total of 25 UC patients (pts) were included: 44% anti-TNF-naïve. Endoscopic response to VDZ was observed in 32% of UC pts, while 56% of pts showed response based on PGA. The VDZ response rate (by PGA) was higher in anti-TNF-naïve pts vs anti-TNF-exposed pts (82% vs 36% responders, respectively). A preliminary analysis was performed on samples from 8 (out of 25) UC pts, profiling &gt;70,000 gut mucosal cells and &gt;25,000 PBMCs. Within the mucosal compartment, at t0 we identified immune cells (50% of all captured cells), stromal cells (10%), and epithelial cells (40%). Upon inflammation, the proportion of immune cells increased to 70%, stromal cells to 20%, while epithelial cells depleted to 10%. Notably, all main identified immune cell lineages – T cells, B cells and myeloid cells – contributed to the expansion of the immune cell compartment in inflamed mucosa. In line with scRNAseq data, we identified all major immune cell populations and detected expression of both the classic gut-directed and the redundant trafficking integrins by Cytek.

Conclusion
The preliminary results substantiate our current understanding of VDZ biology in UC. We confirm that anti-TNF-naïve pts have a higher response rate to VDZ vs anti-TNF-exposed pts. With this unique cohort, our study has the power to further explore molecular mechanisms and pathways that underlie VDZ response at the single-cell level.
P046 Effects of CB2 and TRPV1 stimulation on osteoclast overactivity induced by iron in pediatric inflammatory bowel disease
Authors: Strisciuglio C , Tortora C , Di Paola A , Creoli M , Cenni S , Argenziano M , Martinelli M , Miele E , Rossi F 
Published: January 2022

Abstract

Background
The reduction of bone mineral density and osteoporosis (OP) has an high impact on inflammatory bowel disease (IBD) patients’ health. We have previously shown that a dysregulated iron metabolism occurs in IBD and leads to a decrease in circulating iron concentration and an excessive intracellular sequestration of iron. Studies suggest that iron overload affects the bone, accelerating osteoclasts (OCs) differentiation and activation with consequent bone resorption. The aim of this study was to evaluate the role of Cannabinoid Receptor type 2 (CB2) and transient receptor potential vanilloid type-1 (TRPV1) and of the iron in the development of osteoporosis in pediatric IBD.

Methods
We enrolled 21 young subjects aged less than 18 years stratified into 3 groups on the basis of the clinical diagnosis: 7 with Ulcerative Colitis (UC) 7 with Crohn’s disease (CD) and 7 were non-IBD controls (CTR). We evaluated the role of CB2 and TRPV1 receptors and of iron in the development of OP in pediatric IBD at diagnosis and analyzed the effects of the pharmacological modulation of CB2 and TRPV1 receptors on osteoclast activity and on iron metabolism by Western Blotting, Tartrate-resistant acid phosphatase assay (TRAP assay) and Iron Assay Kit. We evaluated bone resorption through a commercially available kit visualizing and counting the resorption pits with the optical microscope.

Results
We observed higher levels of TRPV1 and lower levels of CB2 in the OCs from UC and CD patients compared to CTR. In IBD patients we found a significant up-regulation of osteoclast markers TRAP and Cathepsin K and a consequent osteoclast hyper-activation. The treatments of OCs from IBD patients with the CB2 agonist JWH-133 and the TRPV1 agonist Resinferatoxin, RTX, led to a significant reduction of osteoclastic hyper-activation affecting bone markers expression, number and size of active OCs, and bone resorption area. We also analyzed the [Fe3+] concentration and the expression of iron metabolism modulators, ferroportin1(FPN-1) and divalent metal transporter1(DMT1), in OCs derived from IBD patients. We demonstrated an increase of [Fe3+] and accordingly a decrease of FPN-1 in both groups of patients and an increase of DMT1 levels. After 48h of exposure to JWH-133 and RTX we observed a significant reduction of DMT1 expression in OCs from IBD patients together with a strong increase of FPN-1.

Conclusion
Our data confirm the well-known role of CB2 and TRPV1 receptors in bone metabolism and suggest that their stimulation can reduce the osteoclast overactivity induced by iron, thus providing new insights into the pathogenesis and in the treatment of pediatric IBD-related bone resorption.
P052 Comparing T cell responses to food antigens in Inflammatory Bowel Disease patients and healthy donors
Authors: Schiffer A , Tran F , Sievers L K , Kümpers J , Hinrichsen H , Seegers B , Bergfeld A , Lessing M , Schreiber S , Bacher P 
Published: January 2022

Abstract

Background
The role of nutrition in Inflammatory Bowel Disease (IBD) remains unclear. Studies about the effects of nutritional components on intestinal inflammation and the gut microbiome, as well as the concept of exclusive enteral nutrition in paediatric Crohn’s Disease (CD) are suggestive of an impact of nutrition on the pathophysiology. However, there is currently a lack of knowledge on how food components may affect IBD. Here, we investigated the T helper (Th) cell response against nutritional antigens in healthy controls and IBD patients.

Methods
We used a highly sensitive and specific method developed in our lab, the antigen reactive T cell enrichment (ARTE), to detect wheat and milk-reactive CD4+ T cells directly ex vivo in blood of healthy controls (n=18), CD (n=17) and Ulcerative Colitis (UC, n=15) patients. Peripheral blood mononuclear cells (PBMC) were incubated with whole antigen lysates and activated T helper cells were identified based on the up-regulation of the activation marker CD154. Magnetic enrichment of CD154 positive cells enabled to collect sufficient numbers of food-reactive T cells for their detailed characterization by multiparameter flow cytometry.

Results
We detected low frequencies of milk and wheat-reactive T cells in healthy individuals. Milk-reactive T cells were less frequent and expressed several markers of T cell exhaustion. In CD, but not UC patients, we identified higher frequencies of food-reactive T cells. These tended to be particularly increased in patients with disease manifestation in the upper gastrointestinal tract. In addition, we observed increased production of inflammatory cytokines of wheat-reactive T cells in CD, compared to healthy controls and UC patients. No ground-breaking differences were identified regarding the expression of exhaustion markers between IBD patients and controls.

Conclusion
Frequencies of food-reactive Th cells are increased in CD and show a proinflammatory cytokine pattern. The Th1-response of wheat-reactive T cells, characterized by high IFN-γ-secretion, might contribute to the perpetuation of chronic intestinal inflammation.
P064 IMU-838, a Small Molecule DHODH Inhibitor in Phase 2 Clinical Trial for Ulcerative Colitis, Shows Potent Anti-inflammatory Activity in Cell-Culture-Based and In Vivo Systems
Authors: Peelen E , Muehler A , Vitt D , Kohlhof H 
Published: January 2022

Abstract

Background
IMU-838 (vidofludimus calcium) is a well-tolerated and orally available small molecule inhibitor of dihydroorotate dehydrogenase (DHODH) and is currently in phase 2 clinical development for ulcerative colitis (UC). Here, we investigated the effect of IMU-838 on different immune cell subsets and analysed the mechanism of action in more detail in T cells.

Methods
The effect of IMU-838 on regulatory macrophages (Mregs) was investigated by adding IMU-838 or anti-TNFα antibodies (infliximab, adalimumab), alone or in combination, in a mixed lymphocyte reaction assay, determining Mregs (CD206+CD14+) by FACS analysis. To investigate the effect of IMU-838 on human T and B cells, PBMC were stimulated with PHA (48h) or Oligonucleotide 2006-PTO (70h), respectively.
An affinity-dependent effect of IMU-838 was assessed on CD8 T cells from OT-I and OT-III mice, containing a high and a low affinity T cell receptor (TCR), respectively, for OVA257-264 peptide. These cells were stimulated with ovalbumin (OVA) peptide loaded splenocytes or anti-CD3/anti-CD28 for 3 days. Oxidative phosphorylation (OXPHOS) and glycolysis in murine T cells was investigated by the Seahorse/Agilent technique in murine CD4 and CD8 T cells activated with anti-CD3/anti-CD28 with or without IMU-838.

Results
IMU-838 slightly induced Mregs, but strongly and dose-dependently decreased TNFα and IL-6 secretion. Anti-TNFα antibodies alone strongly induced Mregs, but also increased IL-6 levels. When IMU-838 was added, Mregs induction was even higher, and IL-6 was reduced. Besides reducing proinflammatory cytokines secreted by macrophages, IMU-838 also inhibits proliferation of activated B and T cells, as well as inflammatory T cell cytokine secretion, IL-17A, IL-17F and IFNγ, and increased apoptosis up to 3-fold compared to vehicle control. By investigating IMU-838’s role on affinity related activity status of T cells, it was shown that IMU-838 strongly inhibited cell proliferation in the peptide stimulated high affinity, but not in the low affinity, CD8 T cells. Peptide stimulated high affinity T cells show an upregulation of OXPHOS and glycolysis pathways, which are involved in the generation of the cell’s energy supply, compared to low affinity cells. IMU-838 strongly inhibited OXPHOS and glycolysis in both CD4 and CD8 T cells.

Conclusion
IMU-838 reduces the proinflammatory immune cell response by inducing Mregs, reducing pro-inflammatory cytokine secretion and reducing immune cell proliferation. DHODH is only important in cells that received a strong stimulus and are highly metabolically active. Therefore, IMU-838 will only specifically target these cells and will still allow for a normal immune response, representing a huge safety advantage for treatment of IBD patients.
P071 Intestinal CD8+ T cell exhaustion is linked to disease activity in ulcerative colitis
Authors: Grigorian M , Salié H , Mayer L S , Globig A M , Hockenjos B , Krimmel L , Thimme R , Bengsch B , Hasselblatt P 
Published: January 2022

Abstract

Background
The immune pathogenesis of ulcerative colitis (UC) has been linked to imbalanced CD4+ T-cell responses while the contribution of CD8+ T cells is less well characterized. Chronically activated CD8+ T cells may become dysfunctional and acquire an exhausted phenotype during chronic viral infection or cancer. Recently, exhausted T cell (Tex) signatures have been proposed as a potential prognostic marker in autoimmune diseases. We therefore set out to characterize features of CD8+ T cell exhaustion in UC patients in more detail.

Methods
Lymphocytes were isolated from peripheral blood and sigmoid biopsies of UC patients in remission (n = 9) and active disease (n = 20). Cytokine production and expression of exhaustion-associated markers were analyzed ex vivo by flow cytometry. Results were correlated with disease activity (Mayo Score) and mucosal inflammation (assessed endoscopically and histologically [Nancy Score]). To further analyze the role of CD8+ T cells within the intestinal tissue microenvironment, Imaging Mass Cytometry (IMC) was applied on sigma biopsies (n= 21).

Results
Analysis of CD8+ Tex marker expression and functionality did not reveal major differences between peripheral blood lymphocytes isolated from UC patients with either active disease or remission as well as healthy controls. In contrast, in the sigmoid colon of patients with active UC, CD8+ T cell numbers were strongly increased. Moreover, expression of exhaustion markers was significantly increased in intestinal CD8+ T cells during active disease compared to remission. These cells also displayed dysfunctional cytokine profile patterns, as assessed by an established functional exhaustion score. This phenotype also closely correlated with clinical, endoscopic and histological markers of UC disease activity. The findings were confirmed by IMC, which revealed the presence of several clusters of CD8+ T cells with an exhaustion signature in inflamed colonic tissues.

Conclusion
Our findings indicate that inflammation in the intestines of UC patients is associated with the induction of CD8+ T-cell responses that phenotypically and functionally resemble Tex. The functional relevance, prognostic value and therapeutic relevance of these exhausted CD8+ T cell signatures in UC need to be analyzed in future studies.
P077 Different granulocyte subsets are involved in the pathogenesis in Crohn’s disease fistula
Authors: Becker drs M , Koelink P , de Krijger M , Bemelman W , de Jonge W , Buskens C , Wildenberg M 
Published: January 2022

Abstract

Background
Early in inflammation granulocytes migrate from the circulation into inflamed areas and rapidly accumulate. They form an important role in first defense as well as the orchestration of downstream immune responses. In the circulation, several different subsets of granulocytes have been described, for example immature, intermediate and mature granulocytes. Surprisingly, despite their abundance and prominent function, this cell type is rarely studied from a tissue perspective, most likely due to their short lifespan ex vivo.
One example of gastrointestinal disease with an extremely high number of granulocytes is the occurrence of perianal fistula which contain a considerable amount of granulation tissue. As curettage of this tissue is part of the treatment, the fistula tract is good source to study tissue derived granulocyte subsets. The aim of this study was to characterize granulocyte subsets in the fistula tract.

Methods
Curettage material of perianal fistula tracts was obtained during surgical intervention from patients with CD (n=15) and cryptoglandular fistulas (n=5). From 2 CD patients venous blood was taken and a ficoll step was performed. Single-cell suspensions were stained with a 35-antibody panel, including CD66, CD14, CD33, CD16 and CD11b. Samples were analyzed using mass cytometry (CyTOF).

Results
Granulocytes, characterized as CD45+CD66a+ cells, were the main cellular component of the fistula tract (64%±24) compared to other immune cells. This was more pronounced in cryptoglandular fistula compared to CD fistula (81% vs. 67%; p=0.019). Within these cells we could differentiate between 4 subsets, mature granulocytes (CD33+CD11b+CD16+), intermediate (CD33intCD11b+CD16int), immature granulocytes (CD33intCD11b-CD16int) and eosinophils (CD33-CD11b-CD16-). Immature granulocytes were the most abundant in de fistula tract (31%±15), closely followed by the mature (30%±23) and intermediate (23±9). No significant difference was seen in the percentages of granulocyte subsets between CD and cryptoglandular fistula.

Conclusion
Here, we show the presence of different subtypes of granulocytes in fistula derived granulation tissue. We show a heterogeneous group of cells ranging from immature neutrophils to mature neutrophils. Due to their high number in active ulcerating tissue, further evaluation of granulocyte subsets and function could be an interesting target for medical treatment options.
P080 ADS024 attenuates weight loss and decreases disease activity in DSS-induced colitis
Authors: Chesnel L , Acton S 
Published: January 2022

Abstract

Background
Ulcerative colitis (UC) is a chronic, idiopathic inflammatory disease characterised by a dysregulated innate and adaptive immune response to gut microbiota that contributes to the perpetuation of colonic inflammation. ADS024 is an orally administered live biotherapeutic product (LBP), comprised of a single strain of Bacillius velezensis, being developed for potential application in the treatment of patients with UC.

Methods
Colitis was induced in 39 mice by exposure to 3% dextran sodium sulfate (DSS)-treated drinking water from Day 0 to Day 5; 6 control animals did not receive DSS. Animals were then dosed with vehicle (PBS; n=15) or ADS024 (n=12) twice daily for 14 days via oral gavage or with comparator anti-p40 mAb (n=12) once daily (IP) on Days 6, 9, 12, 15. All animals were monitored daily for body weight loss, diarrhea, blood in stool, and activity level. Each of these parameters was individually scored according to the disease activity index (DAI) scoring scheme. Animals underwent video endoscopy on Day 19 to assess colitis severity and stool consistency was scored during endoscopy. Following endoscopy on Day 19, all surviving animals were sacrificed, and blood was collected and processed for serum and analysed for metabolomic profile.

Results
Animals in which colitis was induced by exposure to 3% DSS demonstrated significant weight loss, most profoundly from Days 8 to 11, an increase in the composite DAI and increased mean colon weight:length ratios as compared to control animals. Animals treated with ADS024 had improved body weight, starting at 72 hours post-treatment and decreased DAI scoring over the course of the study compared to the vehicle control group (p&lt;0.01 and p&lt;0.05 respectively), comparable to treatment with anti-p40 mAb which has a mechanism of action similar to ustekinumab (Stelara®) approved for the treatment of UC. A trend towards a decrease in the mean colon weight:length ratio was observed in animals treated with ADS024, but there was no difference in mean endoscopy scoring compared to the vehicle control group. DSS treatment altered the serum biochemical profile at day 19 and ADS024 induced changes suggesting a reversion towards the control state.

Conclusion
Oral treatment with ADS024 improved body weight loss, reduced DAI, and resulted in a trend towards reduction in mean colon weight:length ratios in the DSS-induced mouse colitis model. In addition, ADS024 treatment led to a rebalancing of the systemic metabolomic shift caused by DSS exposure.