Introduction

Background
Lymphocyte trafficking to the inflamed gut is one of the hallmarks of Inflammatory Bowel Disease (IBD) pathology. Integrin a4b7 and its ligand MADCAM1 play an important role in targeting immune cells in the bloodstream to mucosal tissues and blocking this pathway using the anti-a4b7 monoclonal antibody Vedolizumab (VDZ) proved to be an effective treatment in IBD. However, VDZ is most efficient in treatment of Ulcerative Colitis (UC) and of colonic rather than ileal Crohn’s Disease (CD), for which the reasons have not been completely understood.

Aims & Methods

Aim:
To compare the expression of ITGA4, ITGB7 and MADCAM1 in gut tissue biopsies from small and large bowel with respect to the underlying severity of tissue inflammation.

Methods:
Differential gene expression analysis was conducted using bulk RNA Sequencing data generated from gut tissue biopsies of the large and small intestine of 611 CD and 315 UC patients enrolled in a multicentred longitudinal Study of a Prospective Adult Research Cohort with IBD (SPARC IBD) obtained from the IBD Plexus program of the Crohn’s and Colitis Foundation. Gene expression levels of ITGA4, ITGB7 and MADCAM1 were compared across ileal, colonic and rectal segments of the intestine and data were then linked to available measures of local inflammation.

Results

Results:
ITGA4, ITGB7 and MADCAM1 were expressed at comparable levels in large vs small bowel biopsies. Expression of MADCAM1 was significantly increased in both ileal and colonic biopsies from patients with moderate to severe CD based on segmental or composite endoscopy score (SES-CD) across all bowel segments. Expression of both ITGA4 and ITGB7 was similarly increased in colonic biopsies of moderate/severe CD patients, whereas only minor changes were observed for both genes in ileal biopsies. Similar findings were obtained from UC patients, where expression of MADCAM1 was significantly increased in inflamed or ulcerated biopsies from both sigmoid colon and cecum as compared to normal appearing biopsies. Expression of ITGA4 and ITGB7 was only increased in inflamed/ulcerated biopsies of the sigmoid colon but not the cecum and correlated with the modified Mayo endoscopic score (MMES).

Conclusion

Conclusion:
Our analysis suggests that influx of leukocytes to inflamed tissue via ITGA4/ITGB7 and MADCAM1 interactions is more common in the distal colon compared to proximal colon or ileum. This provides a possible mechanistic explanation as to why VDZ is most effective in patients with colonic IBD. Further work is needed to understand the differential regulation of cell trafficking to different regions of the gut.

Introduction

The LIR!C trial demonstrated that laparoscopic ileocaecal resection (ICR) is a cost-effective alternative to infliximab therapy (IFX) in patients with uncomplicated ileocaecal Crohn’s disease (CD), with comparable quality of life outcomes. The aim of this study was to assess the 10-year follow-up of patients enrolled in the LIR!C trial.

Aims & Methods

This retrospective follow-up study included patients from the original LIR!C trial, a multicentre randomized controlled trial comparing ICR to IFX treatment in patients with ileal CD. Long term follow-up data were collected between February 3 and April 14, 2025. Data extraction was focused on initiation or switch of IBD treatments (corticosteroids, immunomodulators and/or advanced medical therapies) and (re)-resections. The follow-up period ranged from trial enrolment to the last visit with the gastroenterologist or surgeon. Primary outcomes were: (1) proportion of patients in clinical remission without therapy switch (no medical therapy or re-resection in the ICR group, and continuation or the cessation of IFX in case of remission in the IFX group), and (2) therapy-free remission, defined as clinical remission without IBD medication and (re)resections.

Results

Follow-up data were available from 60 ICR patients and 57 IFX patients (87% of 134 patients originally included). The median follow-up time was 12 years (IQR 9-14). The clinical remission rate without therapy switch was 40% in the ICR group compared to 26.3% in the IFX group (p=0.117). Of the 60 ICR patients, 24 (40%) had no additional therapy, 13 (21.7%) received an immunomodulator, 18 (30%) biological therapy and 5 (8.3%) underwent a second resection after biological treatment. In the IFX group, 33 (57.9%) required an ICR of whom 25 (75.8%) had previously received second-line biological treatment. Additionally, 7/57 patients (12.3%) were therapy free, 8 (14%) continued IFX treatment, 6 (10.5%) received other biological treatment, and 3 (5.3%) switched to an immunomodulator. Therapy-free remission was significantly higher in the ICR group when compared to the IFX group (40% vs 12%, p < 0.001).

Conclusion

After 10 years of follow-up, the clinical remission rate without therapy switch was comparable between both groups, highlighting the long-term durability of both treatment approaches. The majority of IFX patients needed ICR within 10 years of follow-up. 40% of the ICR group did not require any additional therapy further supporting ICR as first-line treatment option in ileal CD.

References

Ponsioen, C. Y., de Groof, E. J., Eshuis, E. J., Gardenbroek, T. J., Bossuyt, P. M. M., Hart, A., Warusavitarne, J., Buskens, C. J., van Bodegraven, A. A., Brink, M. A., Consten, E. C. J., van Wagensveld, B. A., Rijk, M. C. M., Crolla, R. M. P. H., Noomen, C. G., Houdijk, A. P. J., Mallant, R. C., Boom, M., Marsman, W. A., Stockmann, H. B., … LIR!C study group (2017). Laparoscopic ileocaecal resection versus infliximab for terminal ileitis in Crohn's disease: a randomised controlled, open-label, multicentre trial. The lancet. Gastroenterology & hepatology, 2(11), 785–792. https://doi.org/10.1016/S2468-1253(17)30248-0

Disclosure

GD'H served as a consultant for AbbVie, Alimentiv, AstraZeneca, Bristol Myers Squibb, Celltrion, Eli Lilly, Exeliom Biosciences, Johnson & Johnson, Pfizer, and Takeda; and has received speakers bureau fees from AbbVie, Eli Lilly, Pfizer, Bristol Myers Squibb, and Takeda.

Introduction

Type 1 diabetes is a disease of the endocrine pancreas, but it also affects the exocrine part, especially the ductal cells. Several studies have shown that secretin-induced ductal HCO₃^- secretion is reduced in diabetes, however, the underlying mechanism and the effect of diabetes on basal secretion is less known.

Aims & Methods

Our aim is to investigate the effect of diabetes on pancreatic exocrine function. Diabetes was induced in wild type and cystic fibrosis transmembrane conductance regulator (CFTR) knock out mice by i.p. administration of streptozotocin and disease development was confirmed by fasting blood glucose level measurement. Pancreatic ductal fluid and HCO₃^- secretion were measured by fluid secretion measurements and fluorescence microscopy, respectively. Expression of ion transporters were investigated by real-time PCR and immunohistochemistry, whereas TEM was used for the morphological characterization of the pancreas.

Results

​Basal fluid and HCO₃^- secretion are significantly elevated in diabetes. Acute or chronic glucose treatment did not affect HCO₃^- secretion, but inhibition of CFTR significantly reduced it in both normal and diabetic mice. Cl^- efflux and the expression of CFTR, ANO1, NHE-1 and AQP1 increased in diabetes. Secretin-stimulated fluid secretion was also significantly higher in diabetic mice.

Conclusion

Our results show that diabetes increases fluid and HCO₃^- secretion in ductal cells both under basal and stimulated conditions in which the increased function of ion and water transporters, especially CFTR, plays central role.
This study was supported by the National Research, Development and Innovation Office Grant (SNN134497 to VV) and the CFRD-SRC Grant (No.: SRC 007).

Introduction

Crohn's disease (CD) location would influence the risk of complications and therapeutic strategies. The objective of this study was to compare the clinical presentation at diagnosis and the natural history of colonic CD in comparison to ileal CD and ulcerative colitis (UC) in pediatric-onset IBD.

Aims & Methods

All children (< 17 years) with a diagnosis of CD or UC made between 1988 and 2011 in a population-based registry were followed retrospectively until 2013. The presentation at diagnosis, the risks of complications, surgery, hospitalization and exposure to different treatments in ileal CD (L1), colonic CD (L2) and UC were compared. Disease location was defined at diagnosis. In case of extension of the disease (L1 or L2 to L3), follow-up was censored.

Results

A total of 215 L1 patients, 234 L2 patients and 337 UC patients were included. At diagnosis, the proportion of male (L1 53.5%; L2 53.4%; UC 42.7%; p=0.012), age at diagnosis (15.0; 13.7; 14.0 years; p=0.003), family history of IBD (12.6%; 12.7%; 5.0%; p=0.005), diagnostic delay (3.0; 3.0; 2.0 months; p=0.001) and smoking prevalence (11.6%; 8.1%; 5.6%; p=0.041) were different between the three groups. Over the study period, incidence of L1, L2 and UC were 0.65 [0.57-0.74], 0.71 [0.62-0.81] and 1.02 [0.92-1.14] per 100,000 person-years, respectively. Bloody stool and diarrhea at diagnosis was observed in 14.9% respectively; 44.4%; and 91.1% (p < 0.001) and 47.0%; 71.8%; and 65.0% (p < 0.001) of L1, L2 and UC. At diagnosis, granuloma was identified in 12.6% of L1 patients and 31.2% of L2 patients (p<0.001). The risk of extension to L3 was significantly higher in the L2 group than in the L1 group (at 5 years - 37% vs. 14%, p<0.001). L2 location was associated with a lower risk of luminal fistula (HR 0.41 [0.21-0.79], p=0.008) but a higher risk of anoperineal lesion (HR 2.11 [1.29-3.45], p=0.003). The prevalence of extra-intestinal manifestations, articular (p<0.001) and cutaneous (p<0.001) was higher in L2 CD. While the risk of surgery was significantly higher in case of L1 location (at 5 years - 37%, 13% and 13%; p<0.001), the risk of hospitalization (at 5 years - 22%, 39% and 33%; p=0.01), exposure to corticosteroids (at 5 years - 55%, 69% and 67%; p<0.001), immunosuppressants (at 5 years - 47%, 61% and 42% - p<0.001) and anti-TNF (at 5 years - 16%, 35% and 22%; p<0.001) were higher in case of L2 location.

Conclusion

The clinical presentation and evolution of ileal and colonic CD at diagnosis differ significantly. Colonic location is associated with a high risk of perianal CD, extra-intestinal manifestations, hospitalization and exposure to steroids, immunosuppressants and anti-TNFs. These differences could justify different therapeutic approaches in the future.

Introduction

Mirikizumab (miri), a p19-directed IL-23 antibody, showed efficacy in ulcerative colitis (UC)¹. Miri modulates transcripts associated with disease activity and anti-TNF resistance in UC and increases expression of transcripts associated with healthy mucosa². Here, we evaluate the transcription profile of patients with UC who respond to placebo (PBO, 20.6%) or miri 200mg treatment (59.7%) versus non-responders and build a model that can predict response in patients with UC.

Aims & Methods

In the phase 2 AMAC trial (NCT02589665), patients were randomized 1:1:1:1 to receive intravenous PBO (N=63), 50mg miri (N=63), or 200mg miri (n=62) with possible exposure-based dose increases or fixed 600mg miri (n=61) at Week (W)0, 4 and 8. Colonic biopsies were collected at baseline, W12, and W52. An Affymetrix HTA2.0 microarray measured gene expression. Limma comparing values at baseline and W12 determined differentially expressed genes (DEGs). DEGs maintaining their W12 expression level through W52 among responders in either the PBO and miri 200mg arms were designated as similarly expressed genes (DEGSEGs).
XGBoost models³ were trained to predict clinical response (decrease in 9-point Mayo subscore [rectal bleeding, stool frequency, endoscopy] of ≥2 points and ≥35% from baseline [BL] with either a decrease of RB subscore of ≥1 or an RB subscore of 0 or 1) using baseline levels of DEGSEGs and TNF biomarkers. Leave-one-out cross validation of the models using AMAC data and validation experiments by training on the PROTECT data⁴ then predicting in AMAC were used to evaluate our models.

Results

Miri 200mg responders were associated with 84 DEGSEGs, PBO responders were associated with 26 DEGSEGs, and 21 DEGSEGs were common to both. When using the PROTECT data as the training data and AMAC data as the validation cohort, we were able to achieve high ROC-AUC and PR-AUCs using the top 36 (FC > 1.5) miri DEGSEGs (PR-AUC=0.78), or combined (PR-AUC=0.93) gene sets as the features and found that the response prediction was significantly higher in AMAC responders vs. non-responders.

Conclusion

Baseline transcript features were predictive of clinical response in patients with UC treated with miri 200mg and our model distinguished responders from non-responders. Future studies are underway to validate this model.

References

1. Sandborn WJ, et al. Gastroenterology. 2020;158(3):537-549.e10.
2. Steere B, et al. J Crohns Colitis. 2020;S103-S104.
3. Chen T, et al. Proceedings of the 22^nd ACM SIGKDD International Conference. 2016;7285-794.
4. Hyams JS, et al. Lancet Gastroenterol Hepatol. 2017;2(12):855-868.

Disclosure

TJ and KH report no conflicts of interest. WR reports grant support and personal fees from Abbott Laboratories, AbbVie, Aesca, Centocor, Falk Pharma GmbH, Immundiagnostik, and Merck Sharp & Dohme, and personal fees from Aptalis, Celltrion, Danone Austria, Elan, Ferring, Mitsubishi Tanabe Pharma Corporation, Otsuka, PDL BioPharma, Pharmacosmos, Schering-Plough, Shire, Takeda, Therakos, Vifor, Yakult, Amgen, AM Pharma, Astellas, AstraZeneca, Avaxia, Bioclinica, Biogen Idec, Boehringer Ingelheim, Bristol-Myers Squibb, Cellerix, Chemocentryx, Celgene, Covance, Galapagos, Genentech, Gilead Sciences, Grünenthal, ICON, Index Pharma, Inova, Janssen, Johnson & Johnson, Kyowa Hakko Kirin Pharma, Lipid Therapeutics, MedImmune, Millennium, Nestle, Novartis, Ocera, Pfizer, Procter & Gamble, Prometheus, Robarts Clinical Trial, Second Genome, SetPoint Medical, TiGenix, UCB, Zyngenia, and 4SC. BS, CH, NM, and VK are employees and shareholders of Eli Lilly and Company. CM is a former employee of Eli Lilly and Company. GD has served as an advisor for: AbbVie, Ablynx, Active Biotech, AgomAb Therapeutics, Allergan, AlphaBiomics, Amakem, Amgen, AM-Pharma, Applied Molecular Therapeutics, Arena Pharmaceuticals, AstraZeneca, Avaxia Biologics, Biogen, Boehringer Ingelheim, Bristol Myers Squibb/Celgene, Celltrion, Cosmo Pharmaceuticals, Dr. Falk Pharma, DSM Pharmaceuticals, Echo Pharmaceuticals, Eli Lilly and Company, enGene, Exeliom Biosciences, Ferring Pharmaceuticals, Galapagos NV, Genentech/Roche, Gilead Sciences, GlaxoSmithKline, Gossamer Bio, Immunic Therapeutics, Johnson & Johnson, Kintai Therapeutics, Lycera, Medimetrics, Medtronic, Merck Sharp & Dohme, Mitsubishi Pharma, Mundipharma, Nextbiotics, Novo Nordisk, Otsuka, Pfizer, PhotoPills, ProciseDx, ProDigest, Progenity, Prometheus Laboratories/Nestlé, Protagonist Therapeutics, RedHill Biopharma, Robarts Clinical Trials, Salix Pharmaceuticals, Samsung Bioepis, Sandoz, Seres Therapeutics/Nestec/Nestlé, Setpoint, Shire, Takeda, Teva, TiGenix, Tillotts Pharma AG, Topivert, Versant, and Vifor Pharma; and received speaker fees from: AbbVie, Biogen, Ferring Pharmaceuticals, Galapagos NV/Gilead Sciences, Johnson & Johnson, Merck Sharp & Dohme, Mundipharma, Norgine, Pfizer, Samsung Bioepis, Shire, Millenium/Takeda, Tillotts Pharma AG, and Vifor Pharma.

Introduction

Inflammatory bowel disease (IBD) is an idiopathic and chronic disorder that includes ulcerative colitis (UC) and Crohn’s disease (CD). Both diseases are different but show an uncontrolled intestinal immune response that generates tissue inflammation. Dendritic cells (DC) are phagocytic professional antigen presenting cells that link the innate and adaptive immune systems. Indeed, they are the only cell type able to stimulate naïve T cells generating an antigen-specific immune response. In humans, DC can be divided into plasmacytoid (pDC) and c conventional type 1 and 2 (cDC1, cDC2). Although cDC migration towards the GI mucosa is enhanced in IBD, the mechanisms underlying these migrations and whether biological drugs can modulate them are currently unknown.

Aims & Methods

This study aimed to analyze DC migratory capacity towards the GI mucosa, and whether biological drugs with different mechanisms of action can modulate this process in health and IBD.This is a cross-sectional observational postmarketing study where the modulatory effect of different biological treatments on samples from patients with an endoscopic diagnosis of IBD and healthy controls was studied ex vivo. Peripheral blood mononuclear cells (PBMC) were obtained from 15 patients per group and were cultured in presence of golimumab or ustekinumab. Following culture, surface markers expression was determined, assessing the differential effect of biological drugs (if any) over the DC subsets in the different groups. After that, the migratory capacity of circulating DC towards CCL2, CCL25, and MadCam1 from the different study groups was determined. Finally, we evaluated the DC migratory capacities in presence of biological drugs or with culture media alone.

Results

The cDC2 subset showed higher expression levels of β7 and CCR5 compared to cDC1. Golimumab and ustekinumab did not modify the expression of the homing markers in any studied subset in pDC and cDC2.On the contrary, in cDC1 both golimumab and ustekinumab increased CCR6 expression in qCD patients and CCR9 in aUC patients. Regarding to the migratory capacities of the different DC subsets toward intestinal chemoattractants ustekinumab decreased the migratory capacity of cDC2 from CD patients towards a medium supplemented with MadCam1 and increases toward CCL2 in case of cDC1 from CU. In the case of migratory capacities of cDC2 from HC were increased by ustekinumab and golimumab toward CCL2 and CCL25 just in case of golimumab.

Conclusion

cDC2 showed more migratory profile markers than other DC populations. Golimumab and ustekinumab modify the expression of the homing markers just in cDC1 subset. Nevertheless, ustekinumab and golimumab modify the migratory capacities of cDC in IBD patients and HC, but do not exert any effect on pDC. These effects occur in a different manner in CD and UC indicates that the behavior of cDC is different in CD and UC, and that the migration capacity of this subset is not dependent exclusively on homing markers.

Introduction

Mucosa protective effects can be mediated by physical as well as by anti-inflammatory mechanisms of action. For the root extract of marshmallow (Althaea officinalis L., REAo), known to cure mild irritation of stomach/gut mucosa [1], only a physical action had been considered. Recent studies have shown that it also induces regeneration of irritated mucosa [2,3]. Mucosal wound healing depends on the recruitment of several cell types, e.g., endothelial cells, fibroblasts, and macrophages (MΦ). Reactive oxygen species (ROS)-induced damage is associated with mucosal infiltration of activated leukocytes, such as MΦ, which produce excessive ROS and pro-inflammatory cytokines that may overwhelm the antioxidant and immune defenses of the cells and exacerbate mucosal inflammation. Additionally, fibroblasts exhibit a metabolic adaptation to control inflammation-related oxidative stress.

Aims & Methods

We aimed to investigate whether REAo has, on top of its physical effects, also anti-inflammatory/-oxidative properties in human dermal fibroblasts (NHDF), human umbilical vein endothelial cells (HUVEC), and human acute monocytic leukemia (THP-1) differentiated MΦ, critical cellular components of the gastrointestinal and oral mucosa.

The cells were pre-treated with REAo or its final formulation STW 42, containing REAo and selected excipients, followed by incubation with H₂O (pro-oxidative) or lipopolysaccharide (LPS, pro-inflammatory). Intracellular ROS were quantified with DCFDA. The releases of IL-6 and TNF-α were determined by ELISA. THP-1 cells were differentiated into MΦ with 0.1 μg/ml phorbol-12-myristate-13-acetatefor 3–5 days.

Results

Pre-treatment (24 h) of HUVEC, NHDF or THP-1-MΦ with STW 42 or REAo (100-1000 μg/ml) significantly inhibited the H₂O-induced intracellular ROS production by 30.0% to 58.7%. Whereas 24h(HUVEC, NHDF) or 48 h (THP-1-MΦ) pre-treatment with STW 42 or REAo (100-1000 μg/ml) inhibited the LPS-activated IL6 release by 25.0-67.0%. Additionally, 48 h pre-treatment of THP-1-MΦ with 50-500 μg/ml STW 42 or REAo significantly inhibited LPS-induced TNF-α release by 21.5% (50 μg/ml) to 52.0% (500 μg/ml), in comparison with LPS-treated MΦ. The observed effects of STW 42 or REAo were similar to 25-100 μM Diclofenac, which was used as an anti-inflammatory control.

Conclusion

These anti-inflammatory and antioxidant properties may support the benefit of STW 42 and its constituent REAo in patients with mucosal irritation with subsequent irritative cough or gastric complaints due to its protective/reparative effects on the mucosa.

References

1. HMPC of EMA 2016. European Union herbal monograph on Althaea officinalis L., radix. EMA/HMPC/436679/2015
2. Deters A, Zippel J, Hellenbrand N, Pappai D, Possemeyer C, Hensel A. 2010. Aqueous extracts and polysaccharides from Marshmallow roots (Althea officinalis L.): Cellular internalisation and stimulation of cell physiology of human epithelial cells in vitro. J Ethnopharmacol. 127: 62-9. doi: 10.1016/j.jep.2009.09.050.
3. Bonaterra GA, Schmitt J, Schneider K, Schwarzbach H, Aziz-Kalbhenn H, Kelber O, Müller J, Kinscherf R. Phytohustil^® and root extract of Althaea officinalis L. exert anti-inflammatory and anti-oxidative properties and improve the migratory capacity of endothelial cells in vitro. Front Pharmacol. 2022 Dec 8;13:948248.
   

Disclosure

JS and NS have nothing to disclose. GAB and RK received project support from Steigerwald Arzneimittelwerk GmbH, Darmstadt, Germany. OK, HAK and KB are employees of Steigerwald Arzneimittelwerk GmbH, Darmstadt, Germany.