Target In Inflammatory Bowel Disease Research Articles

Ursodeoxycholic acid: a promising therapeutic target for inflammatory bowel diseases?

The secondary bile acid ursodeoxycholic acid (UDCA) has long been known to have medicinal properties. As the therapeutically active component of bear bile, it has been used for centuries in traditional Chinese medicine to treat a range of conditions, while manufactured UDCA has been used for decades in Western medicine to treat cholestatic liver diseases. The beneficial qualities of UDCA are thought to be due to its well-established cytoprotective and anti-inflammatory actions. In addition to its established role in treating liver diseases, UDCA is now under investigation for numerous conditions associated with inflammation and apoptosis, including neurological, ocular, metabolic, and cardiovascular diseases. Here, we review the growing evidence base from in vitro and in vivo models to suggest that UDCA may also have a role to play in the therapy of inflammatory bowel diseases.

Time-to-reach Target Calprotectin Level in Newly Diagnosed Patients With Inflammatory Bowel Disease.

Treatment targets in inflammatory bowel disease (IBD) move away from controlling symptoms towards complete recovery of the intestinal mucosa. Currently, the most frequently used noninvasive surrogate marker of mucosal healing is a faecal calprotectin concentration in the target range. This study tested if there was a relation between time-to-reach target calprotectin and first flare. We prospectively included new-onset IBD patients ages 17 and younger in a cloud-based registry (FastForwardCare) and followed them for at least 52 weeks. They were treated according to Dutch national guidelines that advocate a step-up approach. Time-to-reach target was defined as the first calprotectin measurement below 250 μg/g after the start of induction therapy. Time-to-first flare was the time from the first calprotectin measurement below 250 μg/g until reappearance of symptoms with calprotectin values above 250 μg/g. We included 76 patients (luminal Crohn disease [CD] 43); ulcerative colitis [UC] 33). Median age at diagnosis was, respectively 14.5 and 14.1 years. Median time-to-reach target calprotectin was 37 weeks in CD and 11 weeks in UC patients (Log-rank test, P = 0.001). Once the calprotectin target was reached, time-to-first flare was significantly longer in CD than in UC patients (Log-rank test, P = 0.001). CD patients with time-to-reach target calprotectin ≤12 weeks after conventional induction therapy (ie, exclusive enteral nutrition or steroids) had a more favorable disease course in the first year than those with time-to-reach target calprotectin >12 weeks (Log-rank test, P = 0.057). In UC patients, time-to-reach target calprotectin ≤12 weeks is not associated with a favorable disease course in the first year. The findings of this prospective registry suggest that a quick response to conventional therapy predicts a favorable disease course in new-onset paediatric CD, but not in UC. The concept "time-to-reach target calprotectin level" rationalizes the indefinite term "response to treatment" and is well suited for studying treatment effectiveness in real-world practices.

Outcomes and Strategies to Support a Treat-to-target Approach in Inflammatory Bowel Disease: A Systematic Review.

Background and AimsManagement of Crohn’s disease and ulcerative colitis has typically relied upon treatment intensification driven by symptoms alone. However, a ‘treat-to-target’ management approach may help to address underlying inflammation, minimise disease activity at early stages of inflammatory bowel disease, limit progression, and improve long-term outcomes.MethodsA systematic literature review was conducted to identify data relevant to a treat-to-target approach in inflammatory bowel disease, published between January 1, 2007 and May 15, 2017.ResultsConsistent with recommendations of the Selecting Therapeutic Targets in Inflammatory Bowel Disease [STRIDE] working group, studies have investigated factors influencing the achievement of both endoscopic and histological mucosal healing and patient-level outcomes in inflammatory bowel disease [IBD]. Histological healing and biomarker levels have also been shown to be modifiable outcomes. Although there is a lack of prospectively derived evidence validating mucosal healing as a treatment target, data are emerging to suggest that targeting mucosal healing or inflammation rather than symptoms may be cost-effective in some settings. The review highlighted several strategies that may support the implementation of a treat-to-target approach in IBD. The prospective randomised CALM study demonstrated how tight control [whereby treatment decisions are based on close monitoring of inflammatory biomarkers] leads to improvements in endoscopic and clinical outcomes. The review also considered the influence of coordinated care from a multidisciplinary team and patient engagement with improved adherence, as well as the role of therapeutic drug monitoring in inflammatory bowel disease management.ConclusionsA treat-to-target strategy may impact on disease progression and improve outcomes in inflammatory bowel disease. Prospective studies including long-term data are required to ensure that the most appropriate targets and strategies are identified.

Therapeutic targets in inflammatory bowel disease

Abstract Therapeutic goals in inflammatory bowel disease (IBD) have evolved with the introduction of biologic therapies. These medications have demonstrated that resolution of mucosal inflammation was feasible. Mucosal healing has been associated with fewer complications and better patient outcomes. Hence, symptomatic control, which was considered the primary treatment goal, is no longer sufficient. Mucosal healing is now the principal target. Several biomarkers of inflammation have been studied, including C-reactive protein and fecal calprotectin. Although they are helpful in monitoring disease activity, they are still not considered therapeutic targets at this time. Ongoing research is evaluating new biomarkers as potential future targets. Resolution of histological inflammation has also been associated with better outcomes, however, the evidence is limited and the definition of histologic healing is still not clear. Ultimately, restoring quality of life is essential. In recognition of the patient's goals in wellness, patient reported outcomes are part of the therapeutic goals. When combined with mucosal healing endpoints, patient reported outcomes serve as a composite endpoint in IBD clinical trials and now patient care.

Decellularized Human Gut as a Natural 3D Platform for Research in Intestinal Fibrosis.

The current methodologies for the identification of therapeutic targets for inflammatory bowel disease (IBD) are limited to conventional 2-dimensional (2D) cell cultures and animal models. The use of 3D decellularized human intestinal scaffolds obtained from surgically resected intestine and engineered with human intestinal cells may provide a major advancement in the development of innovative intestinal disease models. The aim of the present study was to design and validate a decellularization protocol for the production of acellular 3D extracellular matrix (ECM) scaffolds from the human duodenum. Scaffolds were characterized by verifying the preservation of the ECM protein composition and 3D architecture of the native intestine and were employed for tissue engineering with primary human intestinal myofibroblasts for up to 14 days. Engrafted cells showed the ability to grow and remodel the surrounding ECM. mRNA expression of key genes involved in ECM turnover was significantly different when comparing primary human intestinal myofibroblasts cultured in 3D scaffolds with those cultured in standard 2D cultures on plastic dishes. Moreover, incubation with key profibrogenic growth factors such as TGFβ1 and PDGF-BB resulted in markedly different effects in standard 2D vs 3D cultures, further emphasizing the importance of using 3D cell cultures. These results confirm the feasibility of 3D culture of human intestinal myofibroblasts in intestinal ECM scaffolds as an innovative platform for disease modeling, biomarker discovery, and drug testing in intestinal fibrosis.

Novel Non-biologic Targets for Inflammatory Bowel Disease.

The biologic era revolutionized the medical management of inflammatory bowel disease (IBD) and allowed for a paradigm shift away from a therapeutic strategy that traditionally relied on corticosteroids and immunomodulators. IBD treatment has now further evolved to encompass novel non-biologic agents. An electronic database search, spanning up to September 2018, was conducted using PubMed, Web of Science, Google Scholar, and Scopus. Abstracts were also reviewed from Digestive Diseases Week, European Crohn's and Colitis Organization congress, Canadian Digestive Diseases Week, and United European Gastroenterology Week. The JAK1/3 inhibitor, tofacitinib, was shown to both induce and maintain clinical remission and mucosal healing in ulcerative colitis (UC). Also, the sphingosine-1-phosphate (SIP) S1P1/S1P5 receptor agonist ozanimod showed benefit with clinical remission and mucosal healing in UC. Anti-trafficking non-biologic therapies such as AJM300 and a phosphodiesterase (PDE) PDE4 inhibitor, apremilast, have shown benefit in terms of clinical response, clinical remission, and mucosal healing in UC. Upadacitinib and filgotinib have shown initial favorable outcomes in CD patients, with further ongoing trials. Non-biologic agents comprise a growing number of mechanisms of action with the promise of safe and effective oral therapy for patients with IBD.

Bacterial β-glucuronidase alleviates dextran sulfate sodium-induced colitis in mice: A possible crucial new diagnostic and therapeutic target for inflammatory bowel disease

ObjectiveInflammatory bowel diseases (IBD) including ulcerative colitis and Crohn's disease are devastating diseases of the gut. At present, all the treatments are mainly targeting symptoms like inflammation. The disease remains regarded as incurable, largely due to lacking of knowledge on its etiology. Our previous studies suggested that impaired inactivation of digestive proteases by deconjugated bilirubin in experimental colitis, thus bacterial β-glucuronidase for catalyzing the reaction, may have played critical role in the pathogenesis of IBD. MethodsWe first analyzed β-glucuronidase activity in gut tissue and feces of mice by a colitis model. Then the effect of β-glucuronidase on experimental colitis was investigated in detail by administration of β-glucuronidase (from E. coli) and fecal material transplantation to mice with 3% DSS in drinking water for 7 days. ResultsMice with colitis showed unchanged activity of β-glucuronidase in colon tissue but decreased activity in feces. Treatment with bacterial β-glucuronidase at 100 U or above alleviated DSS-induced colitis as demonstrated by the less body weight loss, less disease activity score, increased expression of tight junction proteins and decreased gut permeability, decreases in MPO, TNF-α, IL-1β, TLR-4 and MyD88, and increase in IL-10 and IκBα in gut, restored fecal β-glucuronidase and gut microbiota along with decreases in fecal digestive proteases. Transplantation of fecal material from control to colitis mice showed similar effects as treatment with β-glucuronidase. ConclusionsBacterial β-glucuronidase showed strong inhibition on colitis along with the reduction in fecal digestive proteases, which may be a crucial diagnostic and therapeutic target for IBD.

Intestinal CD103+CD4+ and CD103+CD8+ T-Cell Subsets in the Gut of Inflammatory Bowel Disease Patients at Diagnosis and During Follow-up.

BackgroundThe integrin CD103 is proposed to be a potential therapeutical target in inflammatory bowel disease (IBD), as it can form a heterodimeric integrin with β7 (Etrolizumab, anti-β7 integrin) on epithelial T cells. Therefore, we aimed to study the frequencies of different intestinal CD103+T-cell subsets, both CD4+ and CD8+, in newly diagnosed, untreated IBD patients at baseline and during follow-up, compared with healthy controls.MethodsIntestinal biopsies from inflamed segments during colonoscopy and peripheral blood samples were prospectively taken from IBD patients at diagnosis and during follow-up. Blood and single cell suspensions from biopsies were analyzed for CD103+ T-cell subpopulations by flow cytometry and expressed as median percentages of the total T-cell population.ResultsIn total, 75 Crohn’s disease (CD) patients, 49 ulcerative colitis (UC) patients, and 16 healthy controls were included. At presentation, IBD patients displayed lower percentages of CD103+T-cell subsets in inflamed biopsies: 3% (1 to 5) CD103+CD4+ in IBD vs 5% (5 to 7) in healthy controls (P = 0.007) and 9% (4 to 15) CD103+CD8+ compared with 42% (23 to 57) in healthy controls (P = 0.001). The majority of intestinal T cells was composed of CD103-CD4+ T cells (65% [52 to 74]) in IBD compared with 30% (21 to 50) in healthy controls (P = 0.001). In patients with endoscopic remission during follow-up (n = 27), frequencies of CD103+ and CD103-T-cell subsets were comparable with healthy controls.ConclusionAt diagnosis, active inflammation in IBD was associated with decreased percentages of both CD103+CD4+ and CD103+CD8+T-cell subsets in colon and ileum biopsies. In active disease during follow-up, these T-cell populations remained low but increased in remission to values comparable with healthy controls. A shift toward more CD103-T cells was observed during active inflammation.

Expert opinion on interleukin-12/23 and interleukin-23 antagonists as potential therapeutic options for the treatment of inflammatory bowel disease

ABSTRACTIntroduction: Blockade of interleukin (IL)-12 and IL-23 is a novel therapeutic target for inflammatory bowel disease (IBD). The monoclonal antibody targeting the shared p40 subunit of IL-12 and IL23, namely ustekinumab, has been approved for Crohn’s disease (CD) and has demonstrated promising results in the treatment of ulcerative colitis. Several agents targeting the IL-23-specific p19 subunit are currently in various stages of development. These newer agents have the potential to provide safety benefits.Areas covered: This review discusses the current state of IL-12/23 and IL-23 antagonists for the treatment of IBD. With multiple biologic classes available, we make recommendations for positioning of these agents in clinical practice.Expert opinion: While tumor necrosis factor (TNF) antagonists remain the biologic of choice for majority of patients with moderate-to-severe IBD, IL-12/23, and IL-23 antagonists should be considered for first- or second-line therapy because of their efficacy in biologic-naïve and experienced patients. Additionally, IL-12/23 and IL-23 antagonists may be preferred over anti-TNF therapy in older patients who are at increased risk for infections and malignancy. The safety compared to anti-TNF may be even greater when one considers that concurrent immunosuppression is probably not necessary when using this class of drug, owing to the low rates of immunogenicity.Trial registration: ClinicalTrials.gov identifier: NCT03398135.Trial registration: ClinicalTrials.gov identifier: NCT03105128.Trial registration: ClinicalTrials.gov identifier: NCT03616821.Trial registration: ClinicalTrials.gov identifier: NCT02891226.Trial registration: ClinicalTrials.gov identifier: NCT03466411.

A Treat-to-Target Update in Ulcerative Colitis: A Systematic Review.

OBJECTIVES:In 2015, the Selecting Therapeutic Targets in Inflammatory Bowel Disease (STRIDE) program proposed shifting the therapeutic focus on ulcerative colitis (UC) toward altering the natural history of the disease course by regularly monitoring objective measurements of disease activity and tailoring treatment accordingly. The therapeutic paradigm shift was well received in the research community and is often cited. However, new evidence on optimal UC treatment targets continues to accumulate since the time of the STRIDE guidelines. This systematic review summarizes the evidence accrued since the STRIDE UC recommendations, discusses the barriers for adoption of treat-to-target approaches in clinical practice in UC, and suggests directions for future research.METHODS:We systematically reviewed MEDLINE for studies from the time of the STRIDE systematic review up to March 31, 2018, that assessed the potential treatment targets identified by the STRIDE recommendations.RESULTS:Each potential treatment target literature search returned > 200 articles, which were then reviewed by 2 independent investigators for relevant studies. Selected studies of clinical factors, patient-reported outcomes, endoscopy, histology, imaging, and biomarkers and implications on treatment targets are summarized.CONCLUSIONS:It appears that the relative weight given to different therapeutic targets in the development and improvement of UC treatments could be optimized, with an increased emphasis on endoscopic and histological targets over clinical or symptomatic targets. For this evolution to occur, however, new research has to demonstrate that the treat-to-target approach will deliver on the promise of better long-term outcomes compared with current approaches.

Transcriptional factor ATF3 protects against colitis by regulating follicular helper T cells in Peyer’s patches

Disruption of mucosal immunity plays a critical role in the pathogenesis of inflammatory bowel disease, yet its mechanism remains not fully elucidated. Here, we found that activating transcription factor 3 (ATF3) protects against colitis by regulating follicular helper T (TFH) cells in the gut. The expression of ATF3 in CD4+ T cells was negatively correlated with the severity of ulcerative colitis in clinical patients. Mice with ATF3 deficiency in CD4+ T cells (CD4creAtf3fl/fl ) were much more susceptible to dextran sulfate sodium-induced colitis. The frequencies of TFH cells, not other T cell subsets, were dramatically decreased in Peyer's patches from CD4creAtf3fl/fl mice compared with Atf3fl/fl littermate controls. The defective TFH cells significantly diminished germinal center formation and IgA production in the gut. Importantly, adoptive transfer of TFH or IgA+ B cells caused significant remission of colitis in CD4creAtf3fl/fl mice, indicating the TFH-IgA axis mediated the effect of ATF3 on gut homeostasis. Mechanistically, B cell lymphoma 6 was identified as a direct transcriptional target of ATF3 in CD4+ T cells. In summary, we demonstrated ATF3 as a regulator of TFH cells in the gut, which may represent a potential immunotherapeutic target in colitis.

Cellular and Molecular Therapeutic Targets in Inflammatory Bowel Disease-Focusing on Intestinal Barrier Function.

The human gut relies on several cellular and molecular mechanisms to allow for an intact and dynamical intestinal barrier. Normally, only small amounts of luminal content pass the mucosa, however, if the control is broken it can lead to enhanced passage, which might damage the mucosa, leading to pathological conditions, such as inflammatory bowel disease (IBD). It is well established that genetic, environmental, and immunological factors all contribute in the pathogenesis of IBD, and a disturbed intestinal barrier function has become a hallmark of the disease. Genetical studies support the involvement of intestinal barrier as several susceptibility genes for IBD encode proteins with key functions in gut barrier and homeostasis. IBD patients are associated with loss in bacterial diversity and shifts in the microbiota, with a possible link to local inflammation. Furthermore, alterations of immune cells and several neuro-immune signaling pathways in the lamina propria have been demonstrated. An inappropriate immune activation might lead to mucosal inflammation, with elevated secretion of pro-inflammatory cytokines that can affect the epithelium and promote a leakier barrier. This review will focus on the main cells and molecular mechanisms in IBD and how these can be targeted in order to improve intestinal barrier function and reduce inflammation.

Novel therapeutic targets in inflammatory bowel disease

SMAD7 antisense oligonucleotides and sphingosine‐1‐phosphate receptor modulators are new oral agents that are being investigated as potential treatments for inflammatory bowel disease (Crohn's disease and ulcerative colitis). This article reports on some of the clinical trial outcomes so far.

Treat to target in inflammatory bowel disease: a survey of treatment strategies amongst Portuguese doctors.

treatment goals in inflammatory bowel disease have changed over the last few years and have shifted from a mainly symptom-based management to objective endpoints, such as mucosal healing and deep remission. A treat-to-target strategy to achieve these goals has been proposed by several experts, although the real-life clinical data is still lacking. This study aimed to investigate the current practices among Portuguese gastroenterologists who treat inflammatory bowel disease patients. Portuguese gastroenterologists were asked to participate in an anonymous online survey. The questions focused on opinions and current practice with regard to treatment targets in inflammatory bowel disease. sixty-two physicians agreed to participate in the survey, 40 were gastroenterology specialists and 22 (35.5%) were fellows. Deep remission was considered as the main treatment goal for Crohn's disease and ulcerative colitis by 82% and 83.9% of the participants, respectively. Mucosal healing as a treatment target was used by 95% and 80% of participants in ulcerative colitis and Crohn's disease, respectively; 71% intensified the treatment to achieve mucosal healing after clinical remission. The most common definition of mucosal healing in Crohn's disease and ulcerative colitis was the absence of mucosal ulceration (32.3%) and a Mayo endoscopic sub-score of 0 (41.9%). Only 3.2% escalated treatment with the aim to achieve histologic remission in ulcerative colitis. a treat-to-target strategy to achieve mucosal healing and deep remission is currently accepted by a substantial number of Portuguese gastroenterologists.

Plasticity of Th17 and Tregs and its clinical importance as therapeutic target in inflammatory bowel disease

The gut immune system is very complex and a single layer of the epithelial barrier along the gastrointestinal tract prevents the evasion of various extracellular commensal and pathogenic microorganisms in the gut mucosa. The inflammatory bowel disease (IBD) consists of ulcerative colitis (UC) and Crohn’s disease (CD). The cause of IBD is thought to be associated with genetic, epigenetic, environmental factors, dietary habits and gut microbiota. Immunologically, the effector CD4+ T cells such as Th1, Th17, and regulatory CD+ T cells play an important role in the pathogenesis of IBD. During gut inflammation and autoimmunity, these cells show phenotypic and functional plasticity, and differentiate into other lineages as well as have mixed-lineage phenotypes such as Th1-Th17, Th1-Treg, and Th17-Treg. The present review discusses the intrinsic and extrinsic factors that affect the cellular and molecular plasticity of Th17 and Treg, their clinical importance, and how plasticity and reprogramming of these cells can be targeted to control the IBD.

The RAGE signaling pathway is involved in intestinal inflammation and represents a promising therapeutic target for Inflammatory Bowel Diseases.

Inflammatory Bowel Diseases (IBD) are chronic inflammatory conditions of the intestinal tract. IBD are believed to result from an inappropriate immune response against the intestinal flora in genetically predisposed patients. The precise etiology of these diseases is not fully understood, therefore treatments rely on the dampening of symptoms, essentially inflammation, rather than on the cure of the disease. Despite the availability of biologics, such as anti-TNF antibodies, some patients remain in therapeutic failure and new treatments are thus needed. The multiligand receptor for advanced glycation end-products (RAGE) is a pattern recognition receptor implicated in inflammatory reactions and immune system activation. Here, we investigated the role of RAGE in intestinal inflammation and its potential as a therapeutic target in IBD. We showed that RAGE was upregulated in inflamed tissues from IBD patients compared to controls. Rage-/- mice were less susceptible to intestinal and colonic inflammation development than WT mice. WT mice treated with the RAGE-specific inhibitor FPS-ZM1 experienced less severe enteritis and colitis. We demonstrated that RAGE could induce intestinal inflammation by promoting oxidative stress and endothelial activation which were diminished by FPS-ZM1 treatment. Our results revealed the RAGE signaling pathway as a promising therapeutic target for IBD patients.

Efficacy and Safety of Abrilumab in a Randomized, Placebo-Controlled Trial for Moderate-to-Severe Ulcerative Colitis

The α4β7 integrin is a validated target in inflammatory bowel disease. This randomized, phase 2b, placebo-controlled, double-blind study evaluated the efficacy and safety of the anti-α4β7 antibody abrilumab in patients with moderate-to-severe ulcerative colitis despite treatment with conventional therapies. Patients (total Mayo Score 6-12, recto-sigmoidoscopy score ≥2) with inadequate response or intolerance to conventional therapies were randomized to receive subcutaneous abrilumab (7, 21, or 70 mg) on day 1, weeks 2 and 4, and every 4 weeks; abrilumab 210 mg on day 1; or placebo. The primary end point was remission (total Mayo Score ≤2 points, no individual sub-score >1 point) for the 2 highest dosages at week 8. Key secondary end points were response and mucosal healing (centrally read) at week8. For 354 patients who received ≥1 dose of investigational product (placebo, n= 116; 7 mg, n= 21; 21 mg, n= 40; 70 mg, n= 98; 210 mg, n= 79), non-adjusted remission rates at week 8 were 4.3%, 13.3%, and 12.7% for the placebo and abrilumab 70-mg and 210-mg groups, respectively (P < .05 for 70 and 210 mg vs placebo); odds of achieving remission were significantly greater with abrilumab 70 mg (odds ratio 3.35; 90% CI 1.41-7.95; P= .021) and 210 mg (odds ratio 3.33; 90% confidence interval 1.34-8.26; P= .030) than with placebo. Response and mucosal healing rates with these dosages also were significantly greater than with placebo. Higher baseline α4β7 levels on naïve CD4+ T cells were a prognostic indicator for overall outcome, but not a predictive biomarker of abrilumab response. There were no cases ofprogressive multifocal leukoencephalopathy or deaths. Abrilumab treatment for 8 weeks induced remission, clinical response, and mucosal healing in patients with moderate-to-severe ulcerative colitis. ClinicalTrials.gov, number NCT01694485.

Involvement of calcium-sensing receptor activation in the alleviation of intestinal inflammation in a piglet model by dietary aromatic amino acid supplementation.

Ca2+-sensing receptor (CaSR) represents a potential therapeutic target for inflammatory bowel diseases and strongly prefers aromatic amino acid ligands. We investigated the regulatory effects of dietary supplementation with aromatic amino acids - tryptophan, phenylalanine and tyrosine (TPT) - on the CaSR signalling pathway and intestinal inflammatory response. The in vivo study was conducted with weanling piglets using a 2×2 factorial arrangement in a randomised complete block design. Piglets were fed a basal diet or a basal diet supplemented with TPT and with or without inflammatory challenge. The in vitro study was performed in porcine intestinal epithelial cell line to investigate the effects of TPT on inflammatory response using NPS-2143 to inhibit CaSR. Dietary supplementation of TPT alleviated histopathological injury and decreased myeloperoxidase activity in intestine challenged with lipopolysaccharide. Dietary supplementation of TPT decreased serum concentration of pro-inflammatory cytokines (IL-1β, IL-6, IL-8, IL-12, granulocyte-macrophage colony-stimulating factor, TNF-α), as well as the mRNA abundances of pro-inflammatory cytokines in intestine but enhanced anti-inflammatory cytokines IL-4 and transforming growth factor-β mRNA levels compared with pigs fed control diet and infected by lipopolysaccharide. Supplementation of TPT increased CaSR and phospholipase Cβ2 protein levels, but decreased inhibitor of NF-κB kinase α/β and inhibitor of NF-κB (IκB) protein levels in the lipopolysaccharide-challenged piglets. When the CaSR signalling pathway was blocked by NPS-2143, supplementation of TPT decreased the CaSR protein level, but enhanced phosphorylated NF-κB and IκB levels in IPEC-J2 cells. To conclude, supplementation of aromatic amino acids alleviated intestinal inflammation as mediated through the CaSR signalling pathway.

Chemokines and Chemokine Receptors as Therapeutic Targets in Inflammatory Bowel Disease; Pitfalls and Promise.

The principal targets for anti-chemokine therapy in inflammatory bowel disease (IBD) have been the receptors CCR9 and CXCR3 and their respective ligands CCL25 and CXCL10. More recently CCR6 and its ligand CCL20 have also received attention, the expression of the latter in enterocytes being manipulated through Smad7 signalling. These pathways, selected based on their fundamental role in regulating mucosal immunity, have led to the development of several therapeutic candidates that have been tested in early phase clinical trials with variable clinical efficacy. In this article, we appraise the status of chemokine-directed therapy in IBD, review recent developments, and nominate future areas for therapeutic focus.

Adhesive Interactions between Mononuclear Phagocytes and Intestinal Epithelium Perturb Normal Epithelial Differentiation and Serve as a Therapeutic Target in Inflammatory Bowel Disease.

Disturbance of intestinal homeostasis is associated with the development of inflammatory bowel disease [IBD], and TGF-β signalling impairment in mononuclear phagocytes [MPs] causes murine colitis with goblet cell depletion. Here, we examined an organoid-MP co-culture system to study the role of MPs in intestinal epithelial differentiation and homeostasis. Intestinal organoids were co-cultured with lamina propria leukocytes and bone marrow-derived dendritic cells [BMDCs] from CD11c-cre Tgfbr2fl/fl mice. Organoid-MP adhesive interactions were evaluated by microscopy, RT-PCR, and flow cytometry. Murine colitis models (dextran sodium sulphate [DSS], CD11c-cre Tgfbr2fl/fl, T-cell-transfer) were used for histological and immunohistochemical analysis. Anti-E-cadherin antibody treatment or CD11c+-cell-specific CDH1 gene deletion were performed for E-cadherin neutralization or knockout. Colonic biopsies from patients with ulcerative colitis were analysed by flow cytometry. Intestinal organoids co-cultured with CD11c+ lamina propria leukocytes or BMDCs from CD11c-cre Tgfbr2fl/fl mice showed morphological changes and goblet cell depletion with Notch signal activation, analogous to CD11c-cre Tgfbr2fl/fl colitis. E-cadherin was upregulated in CD11c+ MPs, especially CX3CR1+CCR2+ monocytes, of CD11c-cre Tgfbr2fl/fl mice. E-cadherin-mediated BMDC adhesion promoted Notch activation and cystic changes in organoids. Anti-E-cadherin antibody treatment attenuated colitis in CD11c-cre Tgfbr2fl/fl and T-cell-transferred mice. In addition, E-cadherin deletion in CD11c+ cells attenuated colitis in both CD11c-cre Tgfbr2fl/fl and DSS-treated mice. In patients with ulcerative colitis, E-cadherin expressed by intestinal CD11c+ leukocytes was enhanced compared with that in healthy controls. E-cadherin-mediated MP-epithelium adhesion is associated with the development of colitis, and blocking these adhesions may have therapeutic potential for IBD.