Introduction

MCL1 immunostaining has been shown in fibroblasts of the fibrotic ileum of CD patients¹ suggesting that senescence of these cells may be a mechanism of fibrosis perpetuation. We aimed to analyse here the expression of senescence markers in murine intestinal fibrosis and to determine the effects, on this process, of galacto-oligosaccharide-functionalized Mesoporous Silica Nanoparticles (NPs) loaded with an anti-MCL1 drug, S63845 (MSN-S63845).

Aims & Methods

MCL1 and β-Galactosidase immunohistochemistry (IHQ) were performed in colons of mice underwent two DSS cycles, obtained from a previous samples collection. C57Bl/6 mice (20–25 g) were drinking DSS at 2% during 2 cycles (a cycle consists in 7 days drinking water with 2% DSS, followed by ten days drinking water). After the first cycle, mice were administered intraperitoneally, 5 days a week, with MSN-S63845 (8 mg/kg), empty MSN, vehicle or S63845 (8 mg/kg), until the end of the experiment. Body weight was monitored daily, and mice were sacrificed 34 days after the beginning of the experiment. A sample from the colon was paraffin embedded for both histological analysis (collagen deposition was quantified by the QuPath software in Syrius Red- stained slides) and MPO IHQ. Other sample was used for RT-PCR studies. The number of CD45, CD3 and Ly6G positive cells in blood was analysed by FACS. Unless other mention, results are expressed as mean±sem.

Results

Both MCL1 and β-galactosidase immunostaining were detected in leukocytes and fibroblasts of the colon of chronic DSS-treated mice. The effects of blocking MCL1, selectively in β-gal positive cells (MSN-S63845), or non-selectively (S63845) did not alter changes in body weight associated to DSS, but significantly increased the colon length (cm) of mice receiving MSN-S63845 (5.9±0.2, P=0.002^**) or S63845 (6.2±0.3, P=0,0402^*) compared with the respective vehicles (5.1±0.1 or 5.2±0.2, respectively). Treatment of MSN-S63845 compared with empty MSN induced a significant diminution in: a) the thickness of the submucosa (32.4±2.9 vs 51.6±5.9, P = 0,024^*), b) the number of MPO positive cells (67±15.7 vs 171.2±15.4, P=0.001^**) c) the mRNA expression of inflammatory cytokines il17 (0.08 (0.02-0.5) vs 1 (0.3-1.6) P=0.03^#), cxcl15 (0.4 (0.2-0.6) vs 0.8 (0.5-3.5) P=0.07) and cxcl5 (0.1 (0.1-1.2) vs 0.5 (0.5-4.2) P=0.048^#) and profibrotic markers, tgfβ1 (0.5±0.04 vs 1.03±0.1, P=0.003^**). In contrast, treatment with S63845 failed to significantly modify any of these parameters. Mice receiving both MSN-S63845 or S63845 exhibited a similar number of CD45, CD3 and Ly6G positive cells in blood than those receiving the respective vehicles.
^#Mann-Whitnney; *t-test

Conclusion

The selective blockade of MCL1 in β-galactosidase positive cells of murine inflamed intestine reduces fibrosis development.

References

1. Seco-Cervera M et al Biochim Biophys Acta Mol Basis Dis. 2024 Feb;1870(2):166966BBA

Introduction

Aims & Methods

Results

Conclusion

Introduction

The intestinal microbiome is now broadly accepted as a key driver of Ulcerative Colitis (UC), but how the gut flora impacts key disease pathologies, such as epithelial barrier dysfunction, is poorly understood. MB310 is a live biotherapeutic product for the treatment of UC comprising 8 gut commensal bacteria. These were selected based on a strong association with clinical response in UC patients when engrafted from the donor in a fecal microbiota transplantation (FMT) clinical study. To understand how the MB310 strains drive clinical benefit, we tested their impact on gut barrier integrity and the epithelial inflammatory response.

Aims & Methods

Effects on barrier function were assessed by measuring electric impedance of Caco-2 cells in the presence or absence of lipopolysaccharide (LPS). Furthermore, effects on epithelial permeability were assessed by measuring the translocation of fluorescein isothiocyanate (FITC)-labelled dextran through a 2-dimensional human colonic organoid-derived monolayer, following treatment with the barrier disruptor dextran sodium sulfate (DSS). To gain a mechanistic insight, transcriptomic analysis of 3-dimensional human colonic organoids was performed, following micro-injection with the MB310 consortium in the presence of inflammatory cytokines (Tumor Necrosis Factor [TNF] and Interferon [IFN]γ).

Results

First, the impact of the MB310 consortium on barrier integrity was explored by co-culturing the strains individually or as a consortium with a monolayer of the gut epithelial cell line, Caco-2. Five MB310 strains, as well as the MB310 consortium, significantly increased the integrity of a gut epithelial cell monolayer. Next, the strains were tested on a Caco-2 monolayer that had been damaged by an inflammatory insult, namely LPS, to reflect active UC. 2 strains enhanced repair of the monolayer after LPS challenge, leading to increased integrity.
Human colonic organoids can be plated out to form a tight monolayer that is impervious to large molecules, such as FITC-dextran. DSS treatment disrupts the monolayer leading to translocation of FITC-dextran. Overnight treatment with the MB310 consortium almost completely reversed this effect, which again demonstrates an ability of MB310 to repair gut epithelium following insult.
Finally, the impact of MB310 on the inflammatory response of the gut epithelium was assessed, by stimulating organoids with inflammatory cytokines to mimic UC conditions. Transcriptomics analysis revealed that the cytokines upregulated several inflammatory genes and pathways. MB310 treatment reversed the activation of many of the inflammatory genes and pathways, including many pathways associated with UC.

Conclusion

The accumulated data suggest that MB310 interacts with the host epithelial barrier leading to improvement of its integrity, repair after damage and reduction of leakiness. Moreover, transcriptomic analysis demonstrated the ability of MB310 to rewire epithelial cells to an anti-inflammatory programme, under inflammatory conditions. COMPOSER-1 is an ongoing phase 1b trial testing MB310 in UC patients.

Introduction

Mitochondrial dynamics refers to coordinated cycles of mitochondrial fission and fusion that allow mitochondrial networks to re-model their shape, distribution and size. These transient processes are involved in multiple cellular functions and the perturbation of mitochondrial dynamics is reported in models of Inflammatory Bowel Diseases (IBD). The role of Dynamin-related protein 1 (Drp1), a critical GTPase for mitochondrial fission, remains understudied in an intestinal disease context.

Aims & Methods

This research aims to examine how mitochondrial networks are altered in mouse and cell culture-based models of intestinal injury and IBD. Cell culture-based assays were performed with the MODE-K intestinal epithelial cell line to explore the role of mitochondrial dynamics in vitro. A Drp1-specific knockout (Drp1 KO MODE-K) was generated using CRISPR-based approaches . Mitochondrial fission was also targeted pharmacologically using P110 and Mdivi-1 fission inhibitors. Intestinal tissue from IBD-related mouse models including TNF^ΔARE (ileitis), Il10^-/- (colitis), Hsp60 ^Δ/ΔIEC (metabolic injury) and Hsp60 ^Δ/ΔIEC;Il10^-/- (metabolic injury/colitis) mice were used for histological analyses and ex vivo organoid cultures. TOM20 was used to stain mitochondrial networks. A novel IBD mouse model with a Drp1 intestinal epithelial cell specific knockout Drp1 ^Δ/ΔIEC;Il10^-/- was generated to assess the role of Drp1-mediated mitochondrial fission in vivo.

Results

TOM20 immunofluorescence staining of mouse tissue sections show that mitochondrial morphology, localisation and mass are diverse under different inflammation and injury-based conditions. The colitis susceptible Il10^-/- mice typically show more fragmented, rounder mitochondria with a decrease in mitochondrial mass compared to Il10^+/+ controls. Hsp60^Δ/ΔIEC mice have a conditional deletion of the Heat shock protein 60 (Hsp60) in the epithelium which results in metabolic injury, a transient tissue injury with irregular tissue architecture and altered mitochondrial metabolism. This Hsp60 loss further accelerates Il10^-/- pathology in Hsp60 ^Δ/ΔIEC;Il10^-/- mice. At day 4 (D4) post tamoxifen treatment, before the onset of crypt loss, Hsp60 ^Δ/ΔIEC;Il10^-/- mice show an increase in a phosphorylated form of Drp1 (pDrp1^Ser616) indicating increased mitochondrial fission. At day 8 (D8), during peak metabolic injury, both Hsp60 ^Δ/ΔIEC;Il10^+/+ and Hsp60 ^Δ/ΔIEC;Il10^-/- mice show a significant increase in mitochondrial mass compared to controls. Furthermore, co-stimulation of ex vivo wild-type organoids with the inflammatory cytokine Tnf and the Drp1-specific inhibitor P110 increases mitochondrial unfolded protein response (UPR) markers at the mRNA level, highlighting the interplay between mitochondrial dynamics and stress responses in injury-based inflammatory conditions. Drp1 KO MODE-K cells also show a noticeable increase in dense, peri-nuclear TOM20 staining when compared to control cells. In extension, the novel Drp1 ^Δ/ΔIEC;Il10^-/- model has proved viable and preliminary data indicates that Drp1 ^Δ/ΔIEC;Il10^+/+ mice have reduced body weights compared to Drp1 ^flox/flox;Il10^+/+ mice. Further characterisation will provide insight into the interplay between Drp1, mitochondrial dynamics and intestinal disease development.

Conclusion

Mitochondrial networks are altered in response to different types of inflammation or injury in models of IBD. Regulated mitochondrial fission and fusion is important for intestinal epithelial cell homeostasis and Drp1 loss or inhibition affects intestinal epithelial cell responses.

Introduction

Vedolizumab (VDZ) is a monoclonal antibody therapy approved in China in 2020 for the treatment of patients with inflammatory bowel disease (IBD; Crohn's disease [CD] and ulcerative colitis [UC])² who were intolerant to conventional therapies.¹ VDZ has a unique, gut-selective, anti-lymphocyte trafficking (GSALT) mechanism of action.³ However, data on the efficacy and safety of VDZ in Chinese patients with IBD in the real-world setting are limited.⁴ This study evaluated the safety of VDZ in adult patients with IBD.

Aims & Methods

VALUE (NCT04872491) was a multicenter, single-arm, prospective, observational study to evaluate the safety of VDZ in adult Chinese patients with IBD (N=500) over a maximum observation period of 72 weeks. Incidence of adverse events (AEs), serious AEs (SAEs), treatment-related adverse drug reactions (ADRs), and AEs of special interest (AESIs) was evaluated. This was the final analysis of the VALUE study conducted in patients with IBD.

Results

A total of 500 patients (UC: n=409; CD: n=91) received VDZ 300 mg. Mean (±standard deviation) age of patients was 44.3 (±15.2) years, and 61.4% (n=307) were male. The mean duration for VDZ exposure was 414 days (UC: 416 days; CD:407 days). A total of 500 patients developed 674 AEs (Table), and the most frequent AEs were infections and infestations (I&I; UC: 115 [28.1%]; CD: 24 [26.4%]), followed by gastrointestinal disorders (GIDS; UC: 87 [21.3%]; CD: 18 [19.8%]). Incidence rates of AEs (/patient-years) were 1.2 and 1.0 in patients with UC and CD, respectively. Overall, 13 (3.2%) patients with UC and 10 (11.0%) with CD had AEs leading to study discontinuation. SAEs were observed in 78 patients with UC and 18 with CD (Table). A total of 19 AESIs were reported by patients with UC and 9 AESIs by those with CD, with the most common AESIs being I&I (UC: 13 [3.2%]; CD: 4 [4.4%]) and malignancy (UC: 3 [0.7%], CD: 2 [2.2%]). The most common I&I disorders reported by patients with UC and CD were Clostridium difficileinfection (4 [1.0%]) and pneumonia (1 [1.1%]), respectively. Overall, 17 (4.2%) patients with UC and 7 (7.7%) with CD had at least 1 AESI. A total of 91 and 15 treatment-related ADRs were observed in patients with UC and CD, respectively; I&I were the most frequently documented ADRs to VDZ treatment (Table). A total of 10 (UC: 5 [1.2%]; CD: 5 [5.5%]) patients treated under concomitant IBD advanced therapy (CIBDAT) experienced a total of 16 AEs (UC: 9; CD: 7), with the most common AEs being I&I (UC: 1 [20.0%]; CD: 2 [40.0%]) and GIDS (UC: 3 [60.0%]; CD: 1 [20.0%]) with CIBDAT. No deaths were reported during the study.

Conclusion

The VALUE study indicated that VDZ was well tolerated in Chinese patients with IBD, with no new safety concerns.

References

1. Scribano ML. World J Gastroenterol. 2018; 24: 2457-2467.
2. Yamamoto S et al., Cureus. 2024;16: e59691.
3. Soler D et al. J Pharmacol Exp Ther. 2009; 330: 864-875.
4. Baili C et al. Am J Gastroenterol. 2023; 118: S213-S214.

Disclosure

This study was funded by Takeda (China) International Trading Co. Ltd. Li Li, Haiyan Zhang, Chengxia Liu, and Xiaomei Sun have no conflicts of interest. Xiaoyu Qian and Fang Zhou are Takeda employees and hold Takeda stock options. Minhu Chen received speaker honorariums from Takeda China, AstraZeneca China, Xian Janssen, and Eisai China.
Medical writing support for the development of this abstract under the direction of the authors was provided by Vibhuti Singh, Ph.D., of Cactus Life Sciences (part of Cactus Communications), funded by Takeda (China) International Trading Co., Ltd.

Introduction

During their lifetime, patients with Crohn's disease (CD) frequently develop strictures as a complication, where various degrees of inflammation and fibrosis coexist. Distinguishing between inflammatory and fibrotic strictures is crucial for deciding on surgery or treatment changes, yet it is currently challenging in clinical practice. Cross-sectional imaging techniques (e.g. magnetic resonance imaging MRI) provide a reasonably accurate estimate of bowel wall fibrosis. However, only histopathological examination can determine its true extent. Radiomics uses artificial intelligence to analyze quantitative features from diagnostic images and can predict clinical outcomes.

Aims & Methods

This study aims to assess the role of radiomics in classifying patients according to the degree (no/mild vs severe) of intestinal fibrosis in a cohort of CD patients who underwent surgery for strictures disease. We retrospectively selected 48 CD patients who underwent MR-enterography and subsequent surgery within 4 months between 2017-2023. An expert pathologist evaluated the degree of fibrosis in histopathological specimens from surgical samples using the Chiorean scoring system from 0 (no fibrosis) to 2 (severe fibrosis), and the degree of inflammation using Geboes score. For each MR-enterography, typical lesions of CD were searched by an expert radiologist on T2-weighted axial images generating a region of interest (ROI) segmentation for each lesion. We extracted 100 radiomic features from each ROI of the pre-processed MRI images using Pyradiomics. Feature selection included univariate analysis (Wilcoxon-Mann-Whitney test) and Spearmann correlation to exclude highly correlated features. A logistic regression model with stepwise regression was built with the selected features and evaluated by computing the area under the curve (AUC) of the receiver operating characteristic (ROC) curve. Model’s sensitivity and specificity were calculated using the best cut-off according to the Youden index method.

Results

Among the 48 patients, 48% (n=23) showed severe fibrosis on the surgical specimen, whereas 52% (n=25) had either no or mild fibrosis. Two radiomic features were selected and resulted statistically significant in the fitted logistic regression model(p < 0.05): original_shape_Maximum2DDiameterColumn and original_firstorder_90Percentile. Results with their 95%CI were: AUC 0.79 (0.64-0-90), sensitivity 0.69(0.50-0.75) and specificity 0.84(0.66-0.94). Bootstrap corrected (mean optimism) values of AUC and metrics were: AUC 0.77 (0.02), sensitivity 0.68(0.01), specificity 0.81(0.02).

Conclusion

Our study suggests that MRI-based radiomics modeling could help predict the degree of intestinal fibrosis. Future research will confirm these findings in a larger cohort.

Introduction

Linked Color Imaging (LCI) is an endoscopic system that emphasizes the red mucosal color to identify subtle areas of inflammation. Endoscopic imaging, including LCI classification and LCI index, has been reported as a predictor of histological healing (HH) in ulcerative colitis (UC). Endoscopic changes (LCI classification, LCI index) in vedolizumab treatment have not been reported to date.

Aims & Methods

This study aimed to evaluate endoscopic remission and HH using LCI endoscopy at week 22 of vedolizumab treatment in patients with moderate to severe UC. This was a phase 4, multicenter, open-label, single-arm, prospective study involving 12 patients with moderately to severely active UC receiving vedolizumab. Vedolizumab was administered for 54 weeks. Endoscopy and mucosal sampling from most inflamed sites or the patient’s rectum when all sites had equal endoscopic severity were performed at weeks 0, 22, and 54 to assess the LCI index, LCI classification, Mayo endoscopic score (MES), Nancy score (If MES = 0, it was collected from the rectum). This study was also evaluated a variety of possible factors such as fecal calprotectin, serum vedolizumab concentration and mucosal gene expression associated with changes induced by vedolizumab. LCI index was numerically evaluated for the redness of a 40-pixel square area within the LCI image. LCI classification was defined by assigning one of the three categories (A, no redness; B, redness with visible vessels; C, intense redness without visible vessels). HH was defined as a Nancy score ≤1, and clinical outcomes were compared between HH and non-HH groups. Correlation coefficients between LCI endoscopy and other clinical markers (MES, Nancy score, fecal calprotectin and vedolizumab concentration) were analyzed at weeks 0, 22, and 54. Gene expression analysis was performed on 374 genes, comparing HH (n=8) vs. non-HH (n=3) and LCI classification A (n=5) vs. LCI classification B and C (n=6) at week 22. Biomarkers common to HH and LCI-A were identified as LCI-Deep remission (L-DR) markers.
The study was registered with the Japan Clinical Trial Registry (Identifier: UMIN000042855).

Results

At week 22, 66.7% (8/12) achieved histological healing (HH), while 50.0% (6/12) met LCI classification A criteria. The LCI index change from baseline showed a statistically significant difference between HH and non-HH (week 22: p=0.021; week 54: p=0.011).Correlation analysis demonstrated that LCI index was significantly associated with: MES (week 22: ρ=0.729, week 54: ρ=0.789), Nancy score (week 22: ρ=0.695, week 54: ρ=0.725), fecal calprotectin (week 22: ρ=0.555, week 54: ρ=0.783), vedolizumab concentration (week 22: ρ=0.758, week 54: ρ=-0.418). Gene expression analysis identified IL1B, CXCL11, CD38, CSF2RB, PTPN6, CD86, NFKB2, IFNAR2, STAT1, GNAI2, FES and IRF9 as L-DR markers, as they were commonly associated with both HH and LCI classification A. There are genes involved in NF-κB signaling pathway and JAK-STAT signaling pathway associated with UC. HH and LCI endoscopy have been found to correlate well but do not perfectly align.
In this study, we proposed a definition of L-DR, which encompasses both HH and LCI endoscopic remission.

Conclusion

This study introduces L-DR as a novel definition for combined endoscopic (LCI-A) and HH (Nancy score ≤1) in UC patients receiving vedolizumab. Additionally, we identified candidate L-DR biomarkers that may serve as potential indicators of deep remission.

Disclosure

Tomohisa Takagi, Male, (Kyoto Prefectural University of Medicine, Kyoto, Japan):
Scholarship funds from Mitsubishi Tanabe Pharma Corporation,
Collaborative research fund from PreMedica Inc.,
Lecture fees by Mochida Pharma. Co., Ltd., Yanssen Pharmaceutical K.K., EA Pharma. Co., Ltd., Mitsubishi Tanabe Pharma Corporation, Towa Pharmaceutical Co., Ltd., Takeda Pharmaceutical Co., Ltd., and Pfizer Japan Inc.
Kazuhiko Uchiyama, Male, ( Kyoto Prefectural University of Medicine, Kyoto, Japan):
Collaboration research fund from Janssen Pharma. K.K.
Lecture fee by Mitsubishi Tanabe Pharma. Co. Ltd. and Janssen Pharma. K.K.
Yuji Naito, Male, (Kyoto Prefectural University of Medicine, Kyoto, Japan):
Scholarship funds from Taiyo Kagaku Co. Ltd., Morinaga Co. Ltd., Miyarisan Pharma Co. Ltd, Morishita-Jintan Co. Ltd., Fujikko Co. Ltd., Mizkan Co. Ltd., Mykinso Co. Ltd.
Collaboration research fund from Takeda Pharma. Co. Ltd. and Taiyo Kagaku Co., Ltd.
Lecture fees by Takeda Pharma. Co. Ltd., Mochida Pharma. Co. Ltd., Biofermin. Co. Ltd., Otsuka Pharma. Co. Ltd., and Miyarisan Pharma. Co. Ltd.