bluuebunny/crossref_metadata_2025_split huggingface dataset:
P0054 Human colonoid-derived monolayers and Caco-2: comparative analysis of inflammatory responses
Authors: Chiara M L , Parente I A , Flammini L , Martina V , Vacondio F , Federica G , de’Angelis G L , Elisabetta B , Bertoni S 
Published: January 2025

Abstract

Background
Given the increasing incidence of inflammatory bowel diseases, there is a growing need for reliable preclinical models that replicate the inflamed intestinal epithelium. Immortalized Caco-2 cells are widely considered the standard in vitro model for intestinal studies, but human-derived colonoid monolayers (CDMs) could be proposed as a powerful alternative to more accurately mimic the pathophysiological features of intestinal inflammation. The present study aims to compare the functional and morphological responses induced by inflammatory cytokines TNFα and IFNγ on CDMs and Caco-2.

Methods
Human colonic crypts from biopsies of 5 healthy volunteers were embedded in Matrigel® and cultured for 5-7 days. IntestiCult™ OGM was used to expand cystic-like colonoids, and single cells were seeded onto coated 24-well inserts. Upon reaching confluence, the medium was switched to IntestiCult™ ODM. Caco-2 cells were cultured for 21 days on 24-well inserts. Differentiated CDMs and Caco-2 monolayers were exposed to 25 ng/mL TNFα-IFNγ for 24 hours. Cell differentiation was assessed by immunocytochemistry (ICC), and barrier integrity was evaluated by transepithelial electrical resistance (TEER) measurement. Cytotoxicity was assessed through the LDH assay. IL-8 and CCL20 release were quantified.

Results
Both models showed increasing TEER over the growth period, indicating the gradual development of epithelial barriers, up to 484±58 Ω*cm2 for CDMs and 700±184 Ω*cm2 for Caco-2. ICC staining for epithelial markers villin and MUC2 confirmed polarization and differentiation under basal conditions in both models, cytokines reduced the expression of epithelial markers. Inflammation reduced the barrier integrity of the monolayers (approximately 18%), although more uniformly in Caco-2 than in CDMs. IL-8 and CCL20 release was augmented by cytokines in both models, (for IL-8 of about 20 times in CDM and 2 times in Caco-2). As regards cell viability, CDMs (40% cytotoxicity) showed higher sensitivity to cytokines than Caco-2 (22% cytotoxicity).

Conclusion
Exposure to an inflammatory environment altered cell morphology and impaired epithelial barrier integrity in both CDMs and Caco-2 monolayers. These findings highlight the potential of CDMs as an advanced model for studying personalized responses in intestinal inflammation.
P0059 Mechanistic understanding of MB310: a consortium of gut commensal bacteria for the treatment of Ulcerative Colitis
Authors: Schreiber F , Villemin C , Sharpington T , Lawley T D , Robinson M J , Bakdash G 
Published: January 2025

Abstract

Background
Microbiotica is developing MB310, a live biotherapeutic product consisting of 8 bacterial strains for the treatment of ulcerative colitis (UC). These were selected based on association with clinical responses in UC patients in a fecal microbiota transplantation (FMT) clinical study. To understand how MB310 drives clinical benefit, we tested their impact on epithelial barrier repair, innate immune cells, and CD4+ T lymphocytes, which are key to the pathology of UC. We also investigated the effects of MB310 bacterial metabolites on the induction of regulatory T (Treg) cells that can counteract UC-associated inflammation.

Methods
Effects on barrier function were assessed by measuring electric impedance of Caco-2 cells in the presence or absence of lipopolysaccharide (LPS). Effects on human dendritic cells (DCs) and M1 macrophages were assessed by determining their cytokine production profile. The effects of MB310 or its metabolites on CD4+ T cells were assessed by measuring their expression of the Treg markers Foxp3 and interleukin (IL)-10 following polarization with MB310-treated DCs. Finally, the induced Treg cells were functionally validated in a T cell suppression assay.

Results
Investigating barrier effects, we observed that five MB310 strains individually increased the integrity of a gut epithelial cell monolayer, and 2 strains repaired the monolayer following damage by LPS challenge. Furthermore, primary human monocyte-derived M1 macrophages and LPS-activated DCs showed an increase in the release of the anti-inflammatory cytokine, IL-10 in comparison to the pro-inflammatory cytokine tumor necrosis factor (TNF), following exposure to all MB310 strains. The MB310-treated DCs were able to enhance IL-10 production by T cells. Investigating the mechanisms of Treg induction, we revealed that the bacterial metabolites from two MB310 strains induced DCs to polarize two distinct subsets of actively suppressive Treg cells: Foxp3+ Tregs and IL-10-producing Tregs. Another MB310 species induced Foxp3+ suppressive Treg cells through direct effect on CD4+ T cells.

Conclusion
The accumulated data suggest that the strains of MB310 interact with the host to oppose key UC disease pathologies by improving gut epithelial barrier integrity; promoting an anti-inflammatory profile of innate immune cells; and inducing Treg cells. Moreover, the metabolites of some MB310 strains lead to induction of different types of functionally suppressive Treg cells. This highlights that multifaceted effects of MB310 that can circumvent the challenge of UC disease heterogeneity, proposing it as a potential therapeutic for a wide spectrum of UC patients. COMPOSER-1 is an ongoing phase 1b trial testing MB310 in UC patients.
P0060 GPR15L counteracts chronic colitis by shaping the intestinal microbiota
Authors: Leggio M , Schramm S , Ocón B , Wirtz S , Puertolas Balint F , Dietz L , Schröder B , Butcher E , Müller T , Neurath M F , Zundler S 
Published: January 2025

Abstract

Background
The G protein-coupled receptor 15 (GPR15) is expressed on gut-homing T cells and the interaction of the GPR15 ligand GPR15L with GPR15 has recently been shown to crucially control integrin-dependent adhesion to the endothelium. However, the impact of GPR15L, which is predominantly expressed by colonic epithelial cells, on experimental colitis and inflammatory bowel disease (IBD) is currently not clear.

Methods
We studied GPR15L in experimental colitis with Gpr15l-deficient and -overexpressing mice as well as with rectal application of recombinant GPR15L. We performed phenotypical and molecular disease characterization using endoscopy, IVIS in vivo imaging, histology, immunofluorescence, FISH, qPCR, and multiplex ELISA. We also performed bulk RNA and metagenomic sequencing. We analyzed the expression of GPR15L in samples from IBD patients and non-IBD controls using qPCR and immunofluorescence and correlated it with clinical information. We explored the function of GPR15L in vitro using radial diffusion assays and antimicrobial assays.

Results
Acute DSS colitis was aggravated in Gpr15l-deficient mice compared to Gpr15l-proficient mice, while it was attenuated in Gpr15l-transgenic mice. This was T cell-independent, since the phenotype was conserved in Rag-/-Gpr15l-/- mice. Moreover, it was independent of Gpr15 in T cell transfer colitis with Gpr15-deficient and -proficient donor cells. RNA sequencing of colon tissue from Gpr15l-/- and Gpr15l+/+ mice with DSS colitis showed differential regulation in genes related to mucosal barrier function and host-microbiota crosstalk. Accordingly, 16S rRNA sequencing revealed a substantial difference in the intestinal microbial diversity of Gpr15l-/- and Gpr15l+/+ mice. Shotgun metagenomics and radial diffusion assays revealed that GPR15L acts as a selective anti-microbial peptide on community and single strain level, respectively, that predominantly restrains the growth of pathogenic bacteria. Rectal supplementation of recombinant GPR15L in Gpr15l-/- mice rescued increased disease severity in acute DSS colitis and reduced bacterial abundance and translocation. Patients with IBD showed reduced expression of GPR15L compared to controls. Furthermore, the expression of GPR15L was lower in patients with high disease severity compared to those with low severity. Finally, flare-free survival in patients with high GPR15L expression was substantially longer than in patients with low GPR15L expression.

Conclusion
GPR15L counteracts experimental colitis and seems beneficial in human IBD. Mechanically, it acts as an anti-microbial peptide to promote the homeostasis of the intestinal microbiota. Thus, GPR15L emerges as a potential future therapeutic approach for IBD.
P0064 Investigating a pathogenic role for IL-18 in Inflammatory Bowel Disease beyond the classical type 1 immunity paradigm
Authors: Grillmaier M , Barendregt D , Calado B , Heredia M , Smits W , Tuk B , van Berkel L , Hulleman-van Haaften D , Klomberg R , Vuijk S , Camman A , Doukas M , de Ridder L , Escher J , Samsom J 
Published: January 2025

Abstract

Background
Crohn’s disease (CD) and ulcerative colitis (UC) are intestinal diseases driven by chronic reactivation of memory T helper (Thm) 1-like and Th17m cells, respectively. Disease remission remains difficult to achieve and maintain due to inter-patient heterogeneity in disease severity and underlying immune responses. Moreover, variations in the pathogenic Thm responses, the treatment target, are understudied. The proinflammatory cytokine IL-18 enhances IL-12-induced IFN-γ production by Th1 cells, as seen in Th1-driven inflammatory diseases. However, its potential pathogenic role in immune-mediated diseases, like CD and UC, is unclear. Upon investigating immune responses in therapy-naïve pediatric CD and UC patients, we detected increased IL-18 plasma concentrations that were correctable by therapy. We hypothesized that IL-18 plays a role in both CD and UC by stimulating Th1m but also Th17m cells, worsening disease.

Methods
We examined therapy-naïve pediatric CD and UC patient plasma proteomics (92 proteins, Proximity Extension Assay technology; CD: n=85, UC: n =31, control: n=25), circulating gut-homing Thm populations, transcriptomes of intestinal biopsies (CD: n=57, UC: n =21, control: n=12), and clinical disease parameters. Further, we assessed cytokine responses by healthy donor-derived Th1m and Th17m cells after IL-18 and IL-12 stimulation in vitro.

Results
Plasma IL-18 concentrations correlated to concentrations of Th1-associated proteins (IFN-γ, CXCL9, CXCL11, CXCL10, PDL1) in CD and UC. Interestingly, in UC patients, IL-18 concentrations also correlated to Th17-associated proteins (IL-12B, IL-17A, IL-24). In agreement, preliminary in vitro data showed that IL-18 + IL-12 stimulation increases IL-17A- and IFN-γ-secreting cell frequencies in CCR6+ Th17m cells. In CD, plasma IL-18 concentrations correlated to frequencies of circulating gut-homing CCR6+CXCR3+CCR4+ Th17m, a pathogenic population known to acquire Th1 features and IFN-γ production. Ileal and colonic mRNA expression of IL-18 pathway genes associated with degree of histological inflammation. Higher IL-18 plasma concentrations at diagnosis associated with moderate to severe disease and worse endoscopic scores in both CD and UC and greater disease extent in UC, suggesting a relationship between IL-18 and disease severity. In line with its preferential production in the ileum, plasma IL-18 concentrations were significantly higher in CD patients with ileal involvement compared to CD patients with colonic disease.

Conclusion
We identify IL-18 as a potential enhancer of both Th1-like and Th17-driven inflammation. High plasma IL-18 is detectable in subgroups of CD and UC patients, raising the question whether IL-18 acts on a specific disease-associated Thm cell population.
P0070 Distinct Serum Proteome Alterations Following Vedolizumab and Ustekinumab Therapy in IBD Patients
Authors: Saliutina M , Cancino C , Juhran K S , Fritz K , Eleftheriadou A M , Velasco Blazquez L , Konopka A , Luo Y , Weidinger C , Sonnenberg E , Siegmund B , Hegazy A N ,   Charité IBD Group
Published: January 2025

Abstract

Background
Inflammatory bowel disease (IBD) is a chronic intestinal disorder characterized by relapse and remission. Dysregulated cytokine networks and excessive immune activation drive intestinal inflammation. Therapies targeting cytokines (e.g., TNF, IL-12/23) and immune cell trafficking (e.g., integrin inhibitors) have been effective. However, the impact of anti-integrin (vedolizumab) and anti-IL-12/23 (ustekinumab) therapies on systemic inflammation is poorly understood. This study compares serum proteome profiles of patients treated with vedolizumab or ustekinumab to elucidate their distinct effects on inflammatory pathways.

Methods
This study included patients with Crohn’s disease (CD), ulcerative colitis (UC), and age- and sex-matched healthy donors (HD), who received either ustekinumab or vedolizumab treatment. The ustekinumab cohort comprised 23 CD and 10 UC patients, while the vedolizumab cohort included 7 CD and 27 UC patients. Serum samples were collected from ustekinumab-treated patients at baseline (week 0) and 8 weeks post-treatment, and from vedolizumab-treated patients at baseline (week 0) and 6 weeks post-treatment. Additionally, serum samples were collected from 32 healthy donors. Proteomic analysis was performed using the Olink Inflammation Panel, measuring 92 inflammation-related proteins. Differential protein expression analysis was conducted to compare baseline and post-treatment samples within each cohort.

Results
Serum proteomic analysis using the Olink Inflammation panel revealed significant alterations in the levels of 15 proteins in IBD patients compared to healthy controls. Pro-inflammatory markers, including 4E-BP1, SIRT2 and TNF were significantly upregulated, indicating immune activation in IBD. Conversely, anti-inflammatory regulators, such as LIF-R and SCF, were significantly downregulated. Ustekinumab treatment led to upregulation of IL-12B and downregulation of 4E-BP1, SIRT2. Notably, IL-12B was upregulated in both CD and UC, while 4E-BP1 and SIRT2 were downregulated in CD (week 8 vs week 0). Conversely, vedolizumab treatment induced robust proteomic changes over time. Between week 0 and week 6, majority of proteins showed significant differential expression, more than the differences observed between IBD and HD groups.

Conclusion
Serum proteomic profiles of IBD patients differ from healthy donors. Ustekinumab induced minimal serum changes, indicating a limited systemic effect, while vedolizumab led to substantial proteomic shifts, suggesting broader modulation of inflammation. These distinct effects highlight the differing mechanisms of ustekinumab and vedolizumab on systemic inflammation in IBD, prompting further investigation to optimize therapeutic strategies.
P0071 Host fecal proteolytic activity is increased following antibiotic treatment in healthy individuals, but not patients with pouchitis
Authors: Werner L , Nissenbaum T , Izhar R , Hirsch A , Fibelman M , Leibovitzh H , Cohen N , Lobel L , Maharshak N 
Published: January 2025

Abstract

Background
Antibiotics (Abx) are crucial for treating infections but significantly disrupt the gut microbiome. While fecal metagenomic studies explored microbial taxa affected by Abx, metaproteomic analyses are lacking. This study investigates how Abx treatment influences host and bacterial activities in healthy individuals and in patients with pouch inflammation (pouchitis).

Methods
We conducted label-free quantitative LC-MS/MS analyses on stool samples from 7 controls and 6 patients with pouchitis, before and after Abx treatment.
Proteins were identified using the unified human gut proteome database. Proteolytic activity was measured in fecal extracts, using a fluorescence kit. Statistical analyses were performed using MSstats in R. p-value&lt;0.05 and Log2fold-change&gt;1 were considered significant after adjustment for multiple comparisons.

Results
Principal component analysis showed that metaproteomes clustered according to disease state and Abx treatment. Before Abx, there was distinct expression of host immune proteins and proteases; as well as of hundreds of microbial proteins, when comparing patients with pouchitis to controls.
In healthy individuals, Abx treatment resulted in diminished protein abundance, (e.g., MUC12) and enrichment of several proteases (CELA2A and CTRC). Concurrently, hundreds of microbial proteins were not expressed after Abx. Pouchitis proteins expression was less affected by Abx, possibly due to a pre-existing dysbiosis.
Comparison of healthy and pouchitis metaproteomes post-Abx treatment revealed enrichment in immunoglobulins and immune proteins (REG1) among pouchitis patients. Conversely, healthy show enrichment in host proteases (CELA3A, TMPRSS15) and serine protease inhibitors. Microbial proteins were also enriched in healthy compared to patients with pouchitis after Abx, though the effect was less pronounced than in pre-Abx samples.
Last, measurements of proteolytic activity in stool extracts, demonstrated that Abx treatment increased proteolytic activity in healthy individuals to levels resembling patients with pouchitis at baseline and post-Abx. Intriguingly, patients with pouchitis showed no further increase in proteolytic activity after Abx treatment.

Conclusion
Proteolytic activity is increased following Abx treatment in healthy individuals, opposed to patients with pouchitis, who exhibit increased proteolytic activity at baseline and post-Abx. The finding that microbial proteins were enriched in healthy compared to pouchitis, before and after Abx, underscores the importance of the microbiome for the homeostasis of the luminal proteolytic activity. Further research is needed to understand how microbial dysbiosis enriches host protease abundance.
P0076 A novel CXCR7 agonist inhibits the intestinal inflammation in Dextran sulfate sodium(DSS)-induced colitis animal model
Authors: Kim Y , Lee Y S , Eun Hee C 
Published: January 2025

Abstract

Background
Inflammatory Bowel Disease (IBD), comprising Ulcerative Colitis (UC) and Crohn's Disease (CD), is a chronic inflammatory disorder characterized by dysregulated immune responses. Chemokines, which play crucial roles in immune regulation, have been implicated in the pathogenesis of IBD. However, the specific function of CXCR7 in IBD pathology remains largely unexplored. In this study, we investigated the therapeutic potential of our newly developed CXCR7 agonist in a preclinical IBD animal model.

Methods
Female C57BL/6J mice were divided into normal, model vehicle, 2 doses of IL21120033 (30, 60 mg/kg), and a positive control group (Cyclosporine A), each with 8-10 mice. Colitis was induced by 2% DSS administration in drinking water for 6 days followed by regular water for 3 days. Vehicle or test compound were administered orally once daily from Day 0-9. The disease activity index (DAI) was measured every day. Following the 9-day treatment period, animals were euthanized and colons were harvested for gross anatomical measurements. Longitudinally bisected colon specimens were either fixed for histopathological evaluation or cryopreserved at -80°c for subsequent IL-6 gene expression analysis.

Results
IL21120033 treatment significantly reduced DAI by 25% and 39% at 30 and 60 mg/kg, respectively. Both colon weight and length showed significant improvement compared to the model vehicle group. Histopathological analysis revealed decreased inflammation scores in IL21120033-treated groups. IL-6 mRNA expression demonstrated dose-dependent reduction following IL21120033 treatment.

Conclusion
IL21120033 demonstrated significant therapeutic efficacy in DSS-induced colitis, representing the first CXCR7 agonist showing beneficial effects in IBD. These findings suggest CXCR7 as a potential therapeutic target for IBD treatment.
P0077 Identification of symbiote candidates for pouchitis in patients with ulcerative colitis
Authors: Uchino M , Son A , Kato T , Nakanishi Y , Hanawa S , Matsuo Y , Ogura H , Ohno H , Ishido S , Nomura K , Tomoo Y , Kusunoki K , Horio Y , Kuwahara R , Ikeuchi H 
Published: January 2025

Abstract

Background
Ulcerative colitis (UC) has been recognized as a life-long inflammatory disease. Although several novel treatments for UC has been developed, medication-uncontrollable UC patients require the surgical treatment. The surgical operation could improve the quality of life of the patients, but requires intensive medical following, because more than 40% develop to pouchitis. We have explored the symbiote candidates for Ileoanal pouch through comprehensive microbiome and metabolome analysis to prove the mechanism of pouchitis.

Methods
The fecal samples in patients with or without pouchitis were collected. 16S rRNA amplicon meta-analysis and metabolome analysis for 170 patients were performed.

Results
The alfa diversity in microbiome was significantly decreased with developing pouchitis. Several bacterial genera which include Lachnospiraceae, Bifidobacteriaceae, Prevotellaceae, Clostridiaceae, Ruminococcaceae, and Veillonellaceae were statistically reduced in correlation with inflammatory clinical score and were shown having significant relation with protective metabolites. In addition, the extent of decrease in these candidates was strikingly prominent in medication-refractory pouchitis. Additionally, some pouchitis revealed the increasing of Enterobacteriaceae, unclassified Lactobacillas, or Propionibacteriaceae.

Conclusion
Thus, our data show these bacterial taxa as symbiote candidates and could be attractive targets for maintenance of Ileal pouch in UC.