Inflammatory Bowel Disease Mucosa Research Articles

Microbial butyrate capacity is reduced in inflamed mucosa in patients with ulcerative colitis

Reduced butyrate-production capacity has been reported in fecal microbial communities in patients with active ulcerative colitis. However, the butyrate-production capacity of the mucosal microbiome from active vs quiescent mucosa in ulcerative colitis has been unexplored. We sought to determine the diversity and relative abundance of mucosal bacterial and fungal communities from endoscopically active vs quiescent mucosa in patients with UC, and aimed to predict contributions of mucosal microbial communities to butyrate synthesis. Systematic, segmental right- and left-sided biopsies were obtained from endoscopically active (n = 13) or quiescent (n = 17) colonic mucosa, among 15 patients with pan-colonic ulcerative colitis. Dietary fiber intake of patients was performed using the validated five-item FiberScreen questionnaire. Amplicon sequencing of mucosal bacteria and fungi was performed. The diversity and relative abundance of mucosal bacterial and fungal taxa were quantified, and predicted contributions to butyrate synthesis were ascertained. Bacterial alpha and beta diversity were similar between active vs quiescent mucosa. Butyrogenic taxa were significantly increased in quiescence, including Butyricimonas, Subdoligranulum, and Alistipes. Predicted butyrate kinase activity was significantly and concomitantly increased in quiescent mucosa. Fiber intake was positively correlated with butyrogenic microbes. Compared to mucosal bacterial prevalence, mucosal fungi were detected in low prevalence. Butyrogenic microbes are relatively increased in quiescent mucosa in ulcerative colitis, and may be related to increased fiber intake during quiescence. Manipulation of the mucosal microbiome towards butyrate-producing bacteria may be associated with endoscopic quiescence.

Gas-propelled nanomotors alleviate colitis through the regulation of intestinal immunoenvironment-hematopexis-microbiota circuits

The progression of ulcerative colitis (UC) is associated with immunologic derangement, intestinal hemorrhage, and microbiota imbalance. While traditional medications mainly focus on mitigating inflammation, it remains challenging to address multiple symptoms. Here, a versatile gas-propelled nanomotor was constructed by mild fusion of post-ultrasonic CaO2 nanospheres with Cu2O nanoblocks. The resulting CaO2–Cu2O possessed a desirable diameter (291.3 nm) and a uniform size distribution. It could be efficiently internalized by colonic epithelial cells and macrophages, scavenge intracellular reactive oxygen/nitrogen species, and alleviate immune reactions by pro-polarizing macrophages to the anti-inflammatory M2 phenotype. This nanomotor was found to penetrate through the mucus barrier and accumulate in the colitis mucosa due to the driving force of the generated oxygen bubbles. Rectal administration of CaO2–Cu2O could stanch the bleeding, repair the disrupted colonic epithelial layer, and reduce the inflammatory responses through its interaction with the genes relevant to blood coagulation, anti-oxidation, wound healing, and anti-inflammation. Impressively, it restored intestinal microbiota balance by elevating the proportions of beneficial bacteria (e.g., Odoribacter and Bifidobacterium) and decreasing the abundances of harmful bacteria (e.g., Prevotellaceae and Helicobacter). Our gas-driven CaO2–Cu2O offers a promising therapeutic platform for robust treatment of UC via the rectal route.

P019 Development of hydrogel systems for targeted rectal delivery of intestinal cells to injured mucosa in inflammatory bowel disease

Abstract Background Crohn’s Disease (CD) and Ulcerative Colitis (UC) are Inflammatory Bowel Diseases (IBD) affecting over 6.8 million people worldwide. CD and UC are chronic and progressive diseases, characterised by destructive inflammation of the intestinal tract. IBD management consists of drugs such as steroids, aminosalicylates, immunosuppressants, and biologics that aim to induce disease maintenance and remission. However, frequent, and systemic drug administration leads to limited local effects, severe side effects, and low patient compliance. Ultimately, about 20% of UC and up to 80% of CD patients require surgical colon removal. Thus, new approaches to locally restore the inflamed mucosa and initiate colonic wound repair are required. Human intestinal organoids (HIOs) are 3D cell aggregates derived from primary tissue or stem cells grown in vitro. They demonstrate a similar composition architecture to the primary intestinal tissue. Studies showed that HIOs can engraft into injured colonic mucosa resulting in wound repair. Thus, delivery of HIOs to damaged intestinal epithelium represents a promising therapeutic option in IBD treatment. The project aims to develop hydrogel systems with embedded HIOs and obtain human-relevant information on their efficacy in the restitution of injured colonic mucosa using an improved and human-relevant organ-on-a-chip technology. Methods A series of thermoresponsive hydrogels were fabricated (based on methylcellulose/hyaluronic acid polymers) and characterised. Following the embedment of HIOs into hydrogels, the morphology and viability of HIOs were determined using microscopy and MTT assays. Inflammation was induced through the administration of LPS to the basolateral side of the gut chip. Hydrogel/HIO systems were applied to the apical chip compartment via flow for 24 hours. Subsequently, hydrogel/HIO systems were removed from the chip, and HIO engraftment into injured mucosa was determined utilising permeability (4 kDa dextran) and cytokine release assays (ELISA IL-8). Results Our findings show that the gels were liquid at 25 °C and solidified at 37 °C and demonstrated low cytotoxicity. Additionally, our results suggest that the hydrogel systems had a restorative and possibly protective effect on the villi structures in the gut chip. Microscopy results clearly demonstrated the presence of fully differentiated villi structures in the chips that were treated with the hydrogel/cell systems (Figure 1B). These villi structures were absent in the not-treated chips (Figure 1A). Conclusion This study suggests that development of organoid-based hydrogels that can serve as a safe, effective, and inexpensive therapy (compared to surgery) and significantly improve the treatment of IBD.

P158 Expression of IL-19 and IL-24 in intestinal mucosa of inflammatory bowel disease: An immunohistochemical study

Abstract Background Interleukins are considered as targets for future inflammatory bowel disease ( IBD) treatments. IL-19 and IL-24 are members of IL-10 family and through the JAK-STAT pathway induce proinflammatory cytokine production. A retrospective single center study was performed to study the IL-19 and IL-24 expression in 121 patients with moderate to severe IBD, before and after treatment with biologics. Methods A retrospective study of 121 patients with moderate to severe IBD was performed using immunochemistry between 1999 and 2017. This study included 72 patients with Crohn's disease (CD), 49 with Ulcerative Colitis (UC) and 20 healthy controls. The age, gender, disease extent, severity and treatment choice were recorded. Endoscopy reports before and after 12 months of treatment were retrieved. Intestinal biopsy samples were retrieved from the Histopathology Lab before and 1 year after treatment with biologics. A signed consent was received from all the patients involved and the study was approved by the Bioethics Committee of Aristotle University of Thessaloniki. The histological specimen were stained for IL-19 and IL-24 before and one year after treatment with biologics. The results were analysed using SPSS for each of the IBD groups (CD, UC) and further to subgroups depending the biologic treatment they received, anti-Tumor Necrosis Factor alpha(anti-TNFa), Vedolizumab (VDZ), Ustekinumab (USK). Results A statistically significant increase was found in IL-19 and IL-24 patients in IBD patients versus healthy controls (P<0.05). On the biologics treated group and the anti-TNFa subgroup, there was statistically significant increase in IL-24 expression post treatment (P<0.01). In UC patients, the IL-24 expression was significantly increased after a successful treatment in relation with Mayo score ( P<0.01). On the CD group, a reverse statistically significant correlation was found between the pre-treatment IL-19 expression and the Harvey Bradshaw Index (H.B.I.) score reduction in the anti-TNFa and the VDZ subgroups (p<0.05). Conclusion A possibly proinflammatory role of IL-19 was found on the CD group. This can be used as a tool in the future to assess the disease activity and support the diagnosis as a diagnostic biomarker, as IL-19 was found normal in healthy controls. An anti-inflammatory role of IL-24 was found especially in the UC group and in relation with the activity index score post-treatment. This can be used potentially as a marker of response to treatment in active UC, assisting the clinical management. Further research is needed to delineate the exact role of these interleukins in intestinal inflammation.

P078 Inflammatory transcriptomic signatures and cell type compositions in colonic mucosa of ulcerative colitis

Abstract Background Previous studies have explored transcriptomic profiles associated with active inflammation in patients with IBD patients, but consistent characteristics of gene expression and enriched pathways, particularly in Asian patients with UC, remain unconfirmed. Here, we aimed to assess distinctive transcriptomic changes associated with persistent active mucosal inflammation in Asian patients with UC despite of medical treatment. Methods We obtained colonic mucosa biopsies of inflamed and noninflamed tissue from 15 patients with UC and 15 healthy controls and performed RNA sequencing analysis. Utilizing publicly available single cell RNA sequencing (scRNAseq) data, we also identified cell types expressing differentially expressed genes from RNAseq data and performed data deconvolution using CIBERSORTx. Results Transcriptomics profiling revealed that the inflammatory transcriptomic signature was highly enriched in the colonic mucosa of UC-active compared to UC-inactive and controls. By incorporating scRNAseq data, the genes upregulated in UC-active were highly expressed in M cells, inflammatory monocytes, and inflammatory fibroblasts, while downregulated genes were prominent in BEST4+ enterocytes and WNT5B+ fibroblasts. Notably, a sub-cluster of enterocytes associated with SAA1, SLC6A14, and DUOXA2 genes exhibited high expression in UC-active. Deconvolution analysis using CIBERSORTx identified significant enrichment of natural killer cells, inflammatory monocytes, Tuft cells, inflammatory fibroblast, WNT2B+Fos-lo1, and pericytes in UC-active. Conclusion Our RNAseq analysis not only identified significant gene expression changes but also revealed shifts in cell type proportions associated with persistent inflammation. These findings offer valuable insights for developing novel treatment strategies for UC.

Transient Mild Photothermia Improves Therapeutic Performance of Oral Nanomedicines with Enhanced Accumulation in the Colitis Mucosa.

The treatment outcomes of oral medications against ulcerative colitis (UC) have long been restricted by low drug accumulation in the colitis mucosa and subsequent unsatisfactory therapeutic efficacy. Here, high-performance pluronic F127 (P127)-modified gold shell (AuS)-polymeric core nanotherapeutics loading with curcumin (CUR) is constructed. Under near-infrared irradiation, the resultant P127-AuS@CURs generate transient mild photothermia (TMP; ≈42°C, 10 min), which facilitates their penetration through colonic mucus and favors multiple cellular processes, including cell internalization, lysosomal escape, and controlled CUR release. This strategy relieves intracellular oxidative stress, improves wound healing, and reduces immune responses by polarizing the proinflammatory M1-type macrophages to the anti-inflammatory M2-type. Upon oral administration of hydrogel-encapsulating P127-AuS@CURs plus intestinal intralumen TMP, their therapeutic effects against acute and chronic UC are demonstrated to be superior to those of a widely used clinical drug, dexamethasone. The treatment of P127-AuS@CURs (+ TMP) elevates the proportions of beneficial bacteria (e.g., Lactobacillus and Lachnospiraceae), whose metabolites can also mitigate colitis symptoms by regulating genes associated with antioxidation, anti-inflammation, and wound healing. Overall, the intestinal intralumen TMP offers a promising approach to enhance the therapeutic outcomes of noninvasive medicines against UC.

Characteristics of flat-type ulcerative colitis-associated neoplasia on chromoendoscopic imaging with indigo carmine dye spraying.

Despite recent advances in endoscopic equipment and diagnostic techniques, early detection of ulcerative colitis-associated neoplasia (UCAN) remains difficult because of the complex background of the inflamed mucosa of UC and the morphologic diversity of the lesions. we aimed to describe the main diagnostic patterns for UCAN in our cohort, including lateral extension surrounding flat lesions. Sixty-three lesions in 61 patients with flat-type dysplasia that were imaged with dye chromoendoscopy (DCE) were included in this analysis. These DCE images were analyzed to clarify the dye-chromoendoscopic imaging characteristics of flat dysplasia, and the lesions were broadly classified into dysplastic and non-dysplastic mucosal patterns. Dysplastic mucosal patterns were classified into two types: small round patterns with round to roundish structures, and mesh patterns with intricate mesh-like structures. Lesions with a nondysplastic mucosal pattern were divided into two major types: a ripple-like type and a gyrus-like type. Of note, 35 lesions (55.6%) had a small round pattern, and 51 lesions (80.9%) had some type of mesh pattern. About 70% of lesions with small round patterns and 49% of lesions with mesh patterns were diagnosed as high-grade dysplasia or carcinoma, while about 30% of lesions with small round patterns and 51% of lesions with mesh patterns were diagnosed as low-grade dysplasia. When a characteristic mucosal pattern, such as a small round or mesh pattern, is found by DCE, the possibility of UCAN should be considered.

A Masking Effect: A Case of Initial Presentation of Ulcerative Colitis After Discontinuing Growth Hormone Therapy.

The inflammation and repair of the intestinal mucosa in inflammatory bowel disease (IBD) involve a complex interplay between innate, adaptive immune responses, and hormones. This may explain the relapsing clinical course of the disease. We present the first reported case of a patient presenting their initial flare of ulcerative colitis immediately after discontinuing growth hormone (GH) therapy, suggesting treatment with GH or growth factors may prevent the development of IBD. This is a case of a 13-year-old female with a history of GH deficiency, presenting with an 8-week history of abdominal pain, blood-stained diarrhea, and fecal calprotectin greater than 8000 mcg/g, 2 weeks after discontinuing GH therapy. The patient subsequently underwent an esophagoduodenoscopy and colonoscopy with biopsies showing histological features consistent with ulcerative colitis. The finding of withdrawing GH or growth factors therapy potentially unmasking IBD in this patient raises a question of whether growth factors can inhibit the development of IBD and suggests beneficial effects of treatment with GH or growth factors as adjuvant therapy for IBD.

Expression of IL-21 and IL-33 in Intestinal Mucosa of Inflammatory Bowel Disease: An Immunohistochemical Study.

Interleukins are considered to be potential therapeutic targets that can alter the prognosis and disease progression of IBD. IL-21 has proven to be involved in effector Th1, Th2 and Th17 responses. Similarly, IL-33, a newly identified cytokine, has been shown to control the Th1 effector response and the action of the colonic Tregs in animal models of colitis and patients with IBD. In this retrospective study, we have studied the expression of these interleukins, using immunohistochemistry, in 121 patients with moderate to severe IBD before and after treatment with biologics. The results were statistically processed using SPSSTM. Increased IL-21 expression was found in the UC and CD groups versus the controls. The IL-33 expression was found to be increased in the post-treatment UC and CD groups, suggesting a protective role of this interleukin against bowel inflammation. The IL-33 expression post-treatment was reversely correlated with the activity index score in CD patients, suggesting a better response to treatment in patients with higher IL-33 mucosa levels. This is the first immunohistochemical study of the expression of those interleukins in bowel mucosa before and after treatment with biologics. These data support a possibly promising future use of these interleukins as biomarkers of severe disease and response to treatment and as potential therapeutic targets for novel monoclonal antibodies.

Hyaluronic acid modified oral drug delivery system with mucoadhesiveness and macrophage-targeting for colitis treatment

Based on the biocompatibility and macrophage targeting of natural polysaccharides, combined with the physiological and pathological characteristics of the gastrointestinal tract and colonic mucosa of ulcerative colitis (UC), we prepare dexamethasone (Dex)-loaded oral colon-targeted nano-in-micro drug delivery systems coated with multilayers of chitosan (CS), hyaluronic acid (HA), and finally Eudragit S100 (ECHCD MPs) using a layer-by-layer coating technique for UC treatment through regulating the M1/M2 polarization of intestinal macrophages. HA/CS/Dex nanoparticles (HCD NPs) are ingested by macrophages via CD44 receptor-mediated endocytosis to regulate M1-to-M2 macrophage polarization and exert anti-inflammatory effects. Moreover, ECHCD MPs show better colon-targeting properties than Dex-loaded chitosan nanoparticles (CD NPs) and HCD NPs which is demonstrated by stronger mucoadhesion to inflamed colon tissues. After oral administration, ECHCD MPs exert significant anti-UC effects. Therefore, ECHCD MPs are proven to be as promising oral colon-targeting drug delivery systems for Dex and have potential application in UC treatment.

Periodontitis and progression of gastrointestinal cancer: current knowledge and future perspective.

Periodontitis is a polymicrobial disorder caused by dysbiosis. Porphyromonas gingivalis (P.gingivalis) and Fusobacterium nucleatum (F.nucleatum) are pathobiont related to periodontitis pathogenesis and were found to be abundant in the intestinal mucosa of inflammatory bowel disease (IBD) and colorectal cancer (CRC) patients. Besides, periodontal infections have been found in a variety of tissues and organs, indicating that periodontitis is not just an inflammation limited to the oral cavity. Considering the possible translocation of pathobiont from the oral cavity to the gastrointestinal (GI) tract, this study aimed to review the published articles in this field to provide a comprehensive view of the existing knowledge about the relationship between periodontitis and GI malignancies by focusing on the oral/gut axis.

Biopsies from ulcer edge yield higher histological activity scores than biopsies from non-ulcerated mucosa in active ulcerative colitis.

The appropriate location for biopsy collection in ulcerative colitis is unknown. We aimed to determine the location for biopsy collection in the presence of ulcers which yields the highest histopathological score. This prospective cross-sectional study enrolled patients with ulcerative colitis and ulcers in the colon. Biopsy specimens were obtained at the edge of the ulcer; at a distance of one open forceps (7-8 mm) from the ulcer edge; at a distance of three open forceps (21-24 mm) from the ulcer edge; further referred to as locations 1, 2 and 3 respectively. Histological activity was assessed using Robarts Histopathology Index and the Nancy Histological Index. Statistical analysis was performed using mixed effects models. A total of 19 patients were included. Decreasing trends with distance from the ulcer edge (P < 0.0001) were observed. Biopsies procured from the edge of the ulcer (location 1) yielded a higher histopathological score compared to biopsies procured at locations 2 and 3 (P ≤ 0.001). Biopsies from the ulcer edge yield higher histopathological scores than biopsies next to the ulcer. In clinical trials with histological endpoints, biopsies should be obtained from the ulcer edge (if ulcers are present) to reliably assess histological disease activity.

P232 Serum neutrophil gelatinase associated lipocalin (NGAL) as a marker of activity of Inflammatory Bowel Disease

Abstract Background Inflammatory bowel disease (IBD) is a disease of activity and remission. Lipocalin 2 (LCN2), the coding gene for NGAL is one of the most over-expressed genes in the colonic mucosa in ulcerative colitis (UC) and crohn’s disease (CD). In our research we investigated the utility of serum level of Lipocalin 2 in assessing the activity of IBD Methods This was a single center case control study.It was conducted on 60 IBD patients, 50% (30 patients) were in remission and 50% were active.There were about 28 healthy control. Patients with IBD either UC or CD were enrolled from IBD clinic Mansoura specialized medical Hospital, Egypt. All patients and control group were subjected to investigations including complete blood count (CBC) ,Erythrocyte Sedimentation Rate (ESR) ,C-reactive protein (CRP),Fecal calprotectin and serum neutrophil gelatinase associated lipocalin (NGAL) by ELISA.Patients only were subjected to sigmoidoscopy or ileo-colonoscopy.The activity of IBD was assessed for UC by MAYO score and CD by CDAI. Results NGAL showed significant increase among active IBD patients by mean± SD ng/ml (37.04 ± 9.63) than patients in remission (20.65± 4.35).It showed highly significant correlation with clinical and endoscopic activity of IBD r= 0.80, P&amp;lt;0.0001. Serum NGAL can easily discriminate patients with active IBD from healthy controls with AUC 95% C.I =1.00 (0.94-1.0), at the cutoff 18.52 , P&amp;lt; 0.0001, with sensitivity 100% and specificity 100%. While AUC of NGAL which can discriminate patients with active IBD and those in remission at the cutoff 26.95 was 0.97, P&amp;lt; 0.0001, with sensitivity 93.3% and specificity 93.3%. In relation to fecal calprotectin, there was highly significant correlation between fecal calprotectin and serum NGAL (r=0.69 , P&amp;lt; 0.0001).Both CRP and ESR were positively correlated to NGAL by r=0.38 and r=0.29 (P&amp;lt;0.05) respectively. Figure (1): NGAL ROC curve among active IBD cases versus healthy controls. Conclusion Serum NGAL can easily discriminate patients with active IBD from healthy controls as well as among patients in active or remission of IBD. NGAL in comparison to other markers as fecal calprotectin or CRP or ESR shows better statistical performance for activity of IBD. This clarifies its ability to be a highly significant predictor of activity of IBD besides its lower cost.

Activation of P2Y1R impedes intestinal mucosa repair during colitis.

Delayed intestinal mucosal healing is one of the pathogenic bases for the recurrence of inflammatory bowel disease (IBD), but how the IBD inflammatory environment impedes intestinal mucosa repair remains unclear. Adenosine diphosphate (ADP) is an endogenous ligand of P2Y1R that is highly produced at sites of inflammation. We herein identify a novel role of ADP to directly facilitate inflammation-induced epithelial permeability, delay wound healing, and disrupt tight junction integrity, and we found that P2Y1R, a receptor preferentially activated by ADP, was significantly upregulated in the colonic mucosa of ulcerative colitis (UC) patients and in colonic epithelial cells of colitis mice. Inhibition of P2Y1R significantly increased the epithelial permeability, decreased the wound healing capacity, and impaired the tight junction integrity in TNF-α-challenged Caco-2 cells. In parallel, the same effects in promoting intestinal mucosa repair were observed in DSS-induced colitis in P2Y1R-/- mice. Mechanistic investigation revealed that P2Y1R inhibition facilitated epithelial AMP-activated protein kinase (AMPK) phosphorylation and gut microbiota homeostasis reconstruction. Taken together, these findings highlight that P2Y1R activation plays an important role in impeding intestinal mucosa repair during colitis, and that P2Y1R is an attractive target for the therapy of IBD.

Reciprocal regulation of protein arginine deiminase 2 and 4 expression in the colonic mucosa of ulcerative colitis

Reciprocal regulation of protein arginine deiminase 2 and 4 expression in the colonic mucosa of ulcerative colitis

Mulberry Biomass-Derived Nanomedicines Mitigate Colitis through Improved Inflamed Mucosa Accumulation and Intestinal Microenvironment Modulation.

The therapeutic outcomes of conventional oral medications against ulcerative colitis (UC) are restricted by inefficient drug delivery to the colitis mucosa and weak capacity to modulate the inflammatory microenvironment. Herein, a fluorinated pluronic (FP127) was synthesized and employed to functionalize the surface of mulberry leaf-derived nanoparticles (MLNs) loading with resveratrol nanocrystals (RNs). The obtained FP127@RN-MLNs possessed exosome-like morphologies, desirable particle sizes (around 171.4 nm), and negatively charged surfaces (-14.8 mV). The introduction of FP127 to RN-MLNs greatly improved their stability in the colon and promoted their mucus infiltration and mucosal penetration capacities due to the unique fluorine effect. These MLNs could efficiently be internalized by colon epithelial cells and macrophages, reconstruct disrupted epithelial barriers, alleviate oxidative stress, provoke macrophage polarization to M2 phenotype, and down-regulate inflammatory responses. Importantly, invivo studies based on chronic and acute UC mouse models demonstrated that oral administration of chitosan/alginate hydrogel-embedding FP127@RN-MLNs achieved substantially improved therapeutic efficacies compared with nonfluorinated MLNs and a first-line UC drug (dexamethasone), as evidenced by decreased colonic and systemic inflammation, integrated colonic tight junctions, and intestinal microbiota balance. This study brings new insights into the facile construction of a natural, versatile nanoplatform for oral treatment of UC without adverse effects.

Identification of a unique subset of tissue-resident memory CD4+ T cells in Crohn’s disease

T cells differentiate into highly diverse subsets and display plasticity depending on the environment. Although lymphocytes are key mediators of inflammation, functional specialization of T cells in inflammatory bowel disease (IBD) has not been effectively described. Here, we performed deep profiling of T cells in the intestinal mucosa of IBD and identified a CD4+ tissue-resident memory T cell (Trm) subset that is increased in Crohn's disease (CD) showing unique inflammatory properties. Functionally and transcriptionally distinct CD4+ Trm subsets are observed in the inflamed gut mucosa, among which a CD-specific CD4+ Trm subset, expressing CD161 and CCR5 along with CD103, displays previously unrecognized pleiotropic signatures of innate and effector activities. These inflammatory features are further enhanced by their spatial proximity to gut epithelial cells. Furthermore, the CD-specific CD4+ Trm subset is the most predominant producer of type 1 inflammatory cytokines upon various stimulations among all CD4+ T cells, suggesting that the accumulation of this T cell subset is a pathological hallmark of CD. Our results provide comprehensive insights into the pathogenesis of IBD, paving the way for decoding of the molecular mechanisms underlying this disease.

Mucosal Addressin Cell Adhesion Molecule 1 Expression Reflects Mucosal Inflammation and Subsequent Relapse in Patients with Ulcerative Colitis.

Mucosal addressin cell adhesion molecule 1 [MAdCAM-1] is upregulated in the vascular endothelium of the colonic mucosa in ulcerative colitis [UC]. Although the association between MAdCAM-1 expression and mucosal inflammation has been discussed, the association with the clinical course of UC patients has not been reported. In this study we investigated not only the association between mucosal MAdCAM-1 expression and mucosal inflammation, but also its association with subsequent relapse in UC patients with clinical remission. Eighty UC patients in remission who visited Kyoto Prefectural University of Medicine for follow-up for 2 years were included. Biopsy samples were collected during colonoscopy, and transcriptional expression levels of UC-related cytokines and MAdCAM-1 were quantified using real-time polymerase chain reaction. MAdCAM-1 mRNA expression and protein expression by immunohistochemistry were compared in patients who subsequently relapsed and those who remained in remission and were examined in relation to endoscopic findings, histological activity and cytokine expression. MAdCAM-1 expression was correlated with endoscopic severity, and significantly elevated in histologically active mucosa than inactive mucosa. Furthermore, MAdCAM-1 expression levels were closely correlated with those of several cytokines. MAdCAM-1 mRNA and protein expression were significantly higher in the relapse group than in the remission group, indicating that MAdCAM-1 expression in the mucosa is already elevated in UC patients in clinical remission who subsequently relapse. MAdCAM-1 expression in the colonic mucosa of UC patients is related to mucosal inflammation and subsequent relapse; it may serve as a marker for both relapse and therapeutic effectiveness in UC.

Hydrogen Sulfide Metabolizing Enzymes in the Intestinal Mucosa in Pediatric and Adult Inflammatory Bowel Disease.

Hydrogen sulfide (H2S) is a toxic gas that has important regulatory functions. In the colon, H2S can be produced and detoxified endogenously. Both too little and too much H2S exposure are associated with inflammatory bowel disease (IBD), a chronic intestinal disease mainly classified as Crohn's disease (CD) and ulcerative colitis (UC). As the pathogenesis of IBD remains elusive, this study's aim was to investigate potential differences in the expression of H2S-metabolizing enzymes in normal aging and IBD. Intestinal mucosal biopsies of 25 adults and 22 children with IBD along with those of 26 healthy controls were stained immunohistochemically for cystathionine-γ-lyase (CSE), 3-mercapto-sulfurtransferase (3-MST), ethylmalonic encephalopathy 1 protein (ETHE1), sulfide:quinone oxidoreductase (SQOR) and thiosulfate sulfurtransferase (TST). Expression levels were calculated by multiplication of the staining intensity and percentage of positively stained cells. Healthy adults showed an overall trend towards lower expression of H2S-metabolizing enzymes than healthy children. Adults with IBD also tended to have lower expression compared to controls. A similar trend was seen in the enzyme expression of children with IBD compared to controls. These results indicate an age-related decrease in the expression of H2S-metabolizing enzymes and a dysfunctional H2S metabolism in IBD, which was less pronounced in children.

Generation of human colon organoids from healthy and inflammatory bowel disease mucosa.

Ulcerative colitis and Crohn's disease are chronic inflammatory bowel diseases (IBD) of unknown cause characterized by a relapsing-remitting behavior. Growing evidence supports the idea that the epithelial barrier plays a central role in the pathogenesis of IBD as well as in its evolution over time, thus representing a potential target for novel therapeutic options. In the last decade, the introduction of 3D epithelial cultures from ex vivo-expanded intestinal adult stem cells (ASCs) has impacted our ability to study the function of the epithelium in several gastrointestinal disorders, including IBD. Here, we describe in detail a reproducible protocol to generate Matrigel-embedded epithelial organoids from ASCs of non-IBD and IBD donors using small colonic biopsies, including steps for its optimization. A slightly modified version of this protocol is also provided in case surgical samples are used. With this method, epithelial organoids can be expanded over several passages, thereby generating a large quantity of viable cells that can be used in multiple downstream analyses including genetic, transcriptional, proteomic and/or functional studies. In addition, 3D cultures generated using our protocol are suitable for the establishment of 2D cultures, which can model relevant cell-to-cell interactions that occur in IBD mucosa.