Mucosal Healing In Inflammatory Bowel Disease Research Articles

Defining mucosal healing in randomized controlled trials of inflammatory bowel disease: A systematic review and future perspective.

Mucosal healing (MH) is an established treatment goal in inflammatory bowel disease (IBD). However, various definitions of MH exist. We aimed to identify how MH is defined in randomized controlled trials (RCTs) in ulcerative colitis (UC) and Crohn's disease (CD). We searched MEDLINE, EMBASE, and the Cochrane library from inception to December 2023 for phase 2 and 3 RCTs of advanced therapies in IBD. One hundred forty-four studies were included, 72 in UC and 72 in CD, published between 1997 and 2023. In UC, 64% (46/72) RCTs reported MH as an endpoint. 12 definitions of MH were found, from endoscopic assessment alone (35/46; 76%) to the more recent combination of histology and endoscopy (10/46; 22%). 96% (44/46) of studies used the Mayo Endoscopic Subscore. In CD, reporting of MH lagged behind UC, with only 12% (9/72) of trials specifically defining MH as an endpoint, 7 as "absence of ulceration," 2 as Simplified Endoscopic Score for CD score ≤2 or 0. Histological assessment was performed in 3 RCTs of CD. Centralized reading of endoscopy was used in 48% (35/72) of RCTs of UC and 22% (16/72) of CD. Only 1 RCT included transmural healing as an endpoint. A standard definition of MH in IBD is lacking. Definitions have evolved particularly in UC, which now includes the addition of histological evaluation. Transmural healing holds promise as a future target in CD. We support a greater standardization of definitions as we expect endpoints to become increasingly stringent and multimodal with computers automating the assessment.

Aloe emodin promotes mucosal healing by modifying the differentiation fate of enteroendocrine cells via regulating cellular free fatty acid sensitivity

The proper differentiation and reorganization of the intestinal epithelial cell population is critical to mucosal regeneration post injury. Label retaining cells (LRCs) expressing SRY-box transcription factor 9 (SOX9) promote epithelial repair by replenishing LGR5+ intestinal stem cells (ISCs). While, LRCs are also considered precursor cells for enteroendocrine cells (EECs) which exacerbate mucosal damage in inflammatory bowel disease (IBD). The factors that determine LRC-EEC differentiation and the effect of intervening in LRC-EEC differentiation on IBD remain unclear. In this study, we investigated the effects of a natural anthraquinone called aloe emodin (derived from the Chinese herb rhubarb) on mucosal healing in IBD models. Our findings demonstrated that aloe emodin effectively interfered with the differentiation to EECs and preserved a higher number of SOX9+ LRCs, thereby promoting mucosal healing. Furthermore, we discovered that aloe emodin acted as an antagonist of free fatty acid receptors (FFAR1), suppressing the FFAR1-mediated Gβγ/serine/threonine-protein kinase (AKT) pathway and promoting the translocation of forkhead box protein O1 (FOXO1) into the nucleus, ultimately resulting in the intervention of differentiation fate. These findings reveal the effect of free fatty acid accessibility on EEC differentiation and introduce a strategy for promoting mucosal healing in IBD by regulating the FFAR1/AKT/FOXO1 signaling pathway.

P755 Long-term need for restart of biologics after withdrawal in patients with Inflammatory Bowel Disease in mucosal healing

Abstract Background In patients with inflammatory bowel disease (IBD) on biologic therapy, once remission has been achieved, withdrawal is a frequent issue in clinical practice that generates uncertainty in aspects such as the reduction of adverse effects and costs, but also the risk of recurrence of activity and the need to restart treatment. The aim of this study was to determine the rate of long-term reintroduction of biologics after withdrawal due to mucosal healing (MH) in IBD, the response to reintroduction and the associated factors. Methods Observational, descriptive, single-centre, retrospective, descriptive study of 178 cases in 164 patients diagnosed with ulcerative colitis (UC) or Crohn's disease (CD) who were withdrawn from anti-tumor necrosis factor (anti- TNF) therapy once MH had been demonstrated, between July 2009 and February 2022. Demographic and phenotypic characteristics of IBD, characteristics of biologic and immunosuppressive therapy, analytical and endoscopic/histological variables at the time of withdrawal were collected. We analysed the risk of restarting biologics due to clinical relapse and response to reintroduction of treatment. We evaluated possible factors related to the risk of restarting treatment and response to treatment. Results We included 178 cases. 123 CD and 55 UC. Most had received infliximab (62.9%) and the main indication was corticodependence (68%). Median follow-up was 78 months (IQR 59-95). Clinical relapse occurred in 69% of cases and 61.2% required reintroduction of biologics, with the probability of retreatment at 1, 3, 5 and 7 years being 19.4%, 50%, 60% and 63.4%, respectively (Figure 1). The response to reintroduction was 86.2%. Only 1.68% required surgery during follow-up. Univariate analysis showed higher risk of re-introduction at younger age at diagnosis (23 vs 30 vs 30, p 0.022) and at withdrawal (32 vs 40, p 0.019) and longer follow-up time after withdrawal (82 vs 71, p 0.026). Multivariate analysis also identified the indication for corticodependence (p 0.046). Conclusion The risk of relapse and re-starting treatment is high in the long term after withdrawal of biologic therapy for MH in IBD. Younger age at diagnosis and withdrawal, indication for corticodependence and long-term follow-up are risk factors for poor outcome. Reintroduction of treatment is very effective with low complication rates.

Emerging strategy towards mucosal healing in inflammatory bowel disease: what the future holds?

For decades, the therapeutic goal of conventional treatment among inflammatory bowel disease (IBD) patients is alleviating exacerbations in acute phase, maintaining remission, reducing recurrence, preventing complications, and increasing quality of life. However, the persistent mucosal/submucosal inflammation tends to cause irreversible changes in the intestinal structure, which can barely be redressed by conventional treatment. In the late 1990s, monoclonal biologics, mainly anti-TNF (tumor necrosis factor) drugs, were proven significantly helpful in inhibiting mucosal inflammation and improving prognosis in clinical trials. Meanwhile, mucosal healing (MH), as a key endoscopic and histological measurement closely associated with the severity of symptoms, has been proposed as primary outcome measures. With deeper comprehension of the mucosal microenvironment, stem cell niche, and underlying mucosal repair mechanisms, diverse potential strategies apart from monoclonal antibodies have been arising or undergoing clinical trials. Herein, we elucidate key steps or targets during the course of MH and review some promising treatment strategies capable of promoting MH in IBD.

Faecalibacterium prausnitzii promotes intestinal epithelial IL-18 production through activation of the HIF1α pathway.

Intestinal epithelial cells produce interleukin-18 (IL-18), a key factor in promoting epithelial barrier integrity. Here, we analyzed the potential role of gut bacteria and the hypoxia-inducible factor 1α (HIF1α) pathway in regulating mucosal IL18 expression in inflammatory bowel disease (IBD). Mucosal samples from patients with IBD (n = 760) were analyzed for bacterial composition, IL18 levels and HIF1α pathway activation. Wild-type Caco-2 and CRISPR/Cas9-engineered Caco-2-HIF1A-null cells were cocultured with Faecalibacterium prausnitzii in a "Human oxygen-Bacteria anaerobic" in vitro system and analyzed by RNA sequencing. Mucosal IL18 mRNA levels correlated positively with the abundance of mucosal-associated butyrate-producing bacteria, in particular F. prausnitzii, and with HIF1α pathway activation in patients with IBD. HIF1α-mediated expression of IL18, either by a pharmacological agonist (dimethyloxallyl glycine) or F. prausnitzii, was abrogated in Caco-2-HIF1A-null cells. Butyrate-producing gut bacteria like F. prausnitzii regulate mucosal IL18 expression in a HIF1α-dependent manner that may aid in mucosal healing in IBD.

The diagnostic and evaluation value of plasma interleukin 9 in the mucosal healing in patients with inflammatory bowel disease treated with biological agents

Objective: To investigate the diagnostic and evaluation value of plasma interleukin 9 (IL9) in the mucosal healing (MH) in patients with inflammatory bowel disease (IBD) treated with biological agents. Methods: Cohort study. IBD patients (137 cases) treated in the Affiliated Suzhou Hospital to Nanjing Medical University (Suzhou Municipal Hospital) from September 2019 to January 2022 were prospective selected. Each patient was treated with biological agents [Infliximab (IFX, 56 cases), Adalimumab (ADA, 20 cases), Ustekinumab (UST, 18 cases), Vedolizumab (VDZ, 43 cases)]. According to different therapeutic drugs, the IFX, ADA, UST, and VDZ group were divided. Clinical symptoms, inflammatory indicators and imaging examinations etc. were evaluated every 8 weeks, and the degree of MH was evaluated by endoscopy at the 54th week. The expression of plasma IL9 was detected by ELISA after initial enrollment (W 0) and 8 weeks of biological treatment (W 8). Receiver operating characteristic curve (ROC) was used to evaluate the diagnostic efficacy of IL9 for MH. Select the cut off value for the optimal ROC threshold based on the highest value of the Youden index. Spearman's rank correlation was used to analyze the correlation between IL9 and Simple Endoscopic Score for CD (SES-CD) and Mayo Endoscopic Score (MES), so as to evaluate the predictive value of IL9 for MH in IBD patients treated with biologic agents. Results: Among the 137 patients, there were 97 Crohn's disease (CD) patients, 53 males and 44 females, aged (31.6±10.3) years (18-60 years). There were 40 ulcerative colitis (UC) patients, 22 males and 18 females, aged (37.5±14.7) years (18-67 years). Among the CD patients, 42 cases (43.3%) achieved MH on endoscopy at the 54th week, and 60 patients (61.9%) achieved clinical remission. Among the UC patients, 22 cases (55.0%) achieved MH and 30 cases (75.0%) achieved clinical remission. At W 0, the relative expression of IL9 in patients in IBD patients who achieved MH after 54 weeks of biological treatment was lower than that in the non-MH patients [x¯±s, (127.42±34.43) vs (146.82±45.64) ng/L, (113.01±44.88) vs (146.12±48.66) ng/L, respectively, both P<0.05]. At W 8, the relative expression of IL9 in the MH group was lower than that in the non-MH patients (both P<0.05). The relative expression of IL9 in the MH patients after IFX treatment was lower than that in the non-MH group (P<0.05). There was no significant difference among the other groups between MH and non-MH patients (all P>0.05). IL9 at W 8 showed high value in predicting MH in IBD [CD patients: area under curve (AUC)=0.716(95%CI: 0.616-0.817, P<0.001), sensitivity and specificity were 80.77%(95%CI:67.64%-88.45%) and 48.89%(95%CI: 35.53%-64.47%), respectively; UC patients: AUC=0.821, sensitivity and specificity were 77.78% and 72.73%, respectively]. At W 8, the cut off values for CD and UC patients were IL9>80.77 ng/L and IL9>77.78 ng/L, respectively. IL9 was positively correlated with endoscopic MH score parameters [M(Q1,Q3),SES-CD: 3.0(8.5, 18.5); MES: 2.0(1.0, 3.0)] (r=0.55, 0.72, respectively, both P<0.001) at W8. Conclusion: The plasma IL-9 at the week 8 after biological agents treatment can be used to diagnose and evaluate the MH of patients with IBD.

Innate Lymphoid Cells as Regulators of Epithelial Integrity: Therapeutic Implications for Inflammatory Bowel Diseases.

The occurrence of epithelial defects in the gut relevantly contributes to the pathogenesis of inflammatory bowel diseases (IBD), whereby the impairment of intestinal epithelial barrier integrity seems to represent a primary trigger as well as a disease amplifying consequence of the chronic inflammatory process. Besides epithelial cell intrinsic factors, accumulated and overwhelmingly activated immune cells and their secretome have been identified as critical modulators of the pathologically altered intestinal epithelial cell (IEC) function in IBD. In this context, over the last 10 years increasing levels of attention have been paid to the group of innate lymphoid cells (ILCs). This is in particular due to a preferential location of these rather newly described innate immune cells in close proximity to mucosal barriers, their profound capacity to secrete effector cytokines and their numerical and functional alteration under chronic inflammatory conditions. Aiming on a comprehensive and updated summary of our current understanding of the bidirectional mucosal crosstalk between ILCs and IECs, this review article will in particular focus on the potential capacity of gut infiltrating type-1, type-2, and type-3 helper ILCs (ILC1s, ILC2s, and ILC3s, respectively) to impact on the survival, differentiation, and barrier function of IECs. Based on data acquired in IBD patients or in experimental models of colitis, we will discuss whether the different ILC subgroups could serve as potential therapeutic targets for maintenance of epithelial integrity and/or mucosal healing in IBD.

Cannabinoid receptor 2 agonist promotes parameters implicated in mucosal healing in patients with inflammatory bowel disease.

Cannabis benefits patients with inflammatory bowel disease (IBD). Cannabinoid receptors are expressed in gut immune cells and in epithelial cells of inflamed guts. Mucosal healing (MH) requires epithelial layer restoration. To analyze the effects of CB2 agonist on parameters implicated in gut inflammation and MH. Mucosal samples from areas of inflamed/uninflamed colon from 16 patients with IBD were cultured without/with cannabinoid receptor 2 (CB2) agonist (JWH-133, 10 µM, 6 hours (hr)), and analyzed for epithelial/stromal cell proliferation, apoptosis (secretome matrix metalloproteinase 9 (MMP9) activity, which impairs epithelial permeability) and interleukin-8 (IL-8) levels (n = 5-9). In addition, Caco-2 (colon carcinoma epithelial cells) were cultured with biopsy secretomes (48 hr), and analyzed for phenotype and protein markers of proliferation (proliferating cell nuclear antigen), autophagy (LC3IIB) and permeability (Zonula occludens-1) (n = 4-6). Uninflamed tissue had higher epithelial proliferation (Ki67: 50%↑, p < 0.05), and reduced secretome MMP9 activity and IL-8 levels (>50%↓, p < 0.05) compared to inflamed tissue. Treatment with CB2 agonist had no effect on epithelial apoptosis, but increased epithelial Ki67 expression (25%), and reduced secretome MMP9 and IL-8 levels in inflamed biopsies. Secretomes of CB2-treated biopsies increased Caco-2 number, migration, proliferating cell nuclear antigen and LC3IIB expression (all, p < 0.05), but had no effect on ZO-1. Using ex vivo and invitro human models, we demonstrated that manipulating the cannabinoid system affects colon cells and secretome characteristics that facilitate MH in IBD.

P556 Long-term probability of retreatment with anti-TNF therapy after discontinuation based on mucosal healing in inflammatory bowel disease

Abstract Background To evaluate the need for retreatment with anti-TNF due to relapse after discontinuation based on mucosal healing in inflammatory bowel disease (IBD), as well as the influencing factors and the response to reintroduction. Methods Descriptive retrospective study of IBD patients in whom anti-TNF treatment was discontinued after mucosal healing had been proved, between June 2009 and May 2016. Demographic and phenotypic characteristics, biologic and immunomodulator (IM) therapy history, laboratory markers and histopathologic evaluation were noted. We evaluated the relapse rate after discontinuation of anti-TNF, as well as the need for reintroduction and its success rate. Results We included 100 patients, 69 of them affected by Crohn’s disease (CD), 29 with ulcerative colitis (UC) and 2 unclassified colitis. From those with CD, inflammatory behaviour (62%) and ileocolonic localisation (53%) were the most frequent conditions. Seventy-four per cent of UC patients had pancolonic involvement. Biological therapy had been indicated because of corticodependence in 66% (vs. 32% corticorefractoriness). The anti-TNF drug was infiliximab in 60 patients, adalimumab in 38, 1 certolizumab and one had been treated with golimumab. Endoscopic biopsies showed quiescent disease in 63 of 83 patients. Eighty-three per cent of patients were treated with IM after removal of anti-TNF. After a mean follow-up of 57 months, 63 patients relapsed, 52 of them needing anti-TNF reintroduction. Reintroduction rates at 12, 36 and 60 months were 19.5%, 43.5% and 52% respectively with a response after the re-treatment of 76,6%. Univariant analysis showed a higher risk in CD (61 vs. 31%, p = 0.008). Within the CD patients, the risk of reintroduction was lower in A3 (30 vs. 66%, p = 0.03) and B2 (31 vs. 69%, p = 0.006) patterns, and higher if the indication had been corticodependence (68% vs. 37%, p = 0.02). Multivariant analysis confirms the protective effect of B2 behaviour and worse outcomes for corticodependence antecedent. Considering UC, the retreatment probability was superior for those patients without IM therapy after anti-TNF discontinuation (57 vs. 22%), although this association did not reach statistical significance (p = 0.08). Conclusion The risk of needing reintroduction of anti-TNF therapy after mucosal healing in IBD is around 50% in 5 years, being superior in CD patients. Reintroduction success rate is 76%. In CD, this risk is higher when the reason for starting anti-TNF was corticodependence, and much lower when stricturing/fibrotic pattern predominates. For UC patients, anti-TNF drugs should not be stopped if IM therapy cannot be held.

Confocal Laser Endomicroscopy in the Evaluation of Inflammatory Bowel Disease.

Inflammatory bowel disease (IBD), including Crohn's disease and ulcerative colitis, can be effectively monitored with the use of endoscopy. The additional application of small field imaging technology such as confocal laser endomicroscopy CLE during ongoing endoscopic evaluation has led to real-time visualization of mucosal abnormalities and thus in vivo histology. The endomicroscopy (CLE) can improve IBD endoscopic evaluation by identifying seemingly normal-appearing mucosa, assessing the function of the intestinal barrier of the epithelium and vascular permeability, and by characterizing any mucosal lesions, including dysplastic lesions. CLE used during conventional endoscopy could especially facilitate the evaluation of mucosal healing in IBD. In addition, future developments in molecular imaging in IBD may optimize therapeutic approaches by identifying mucosal targets for therapy and determining the reasons for lack of response to specific therapy or subsequent loss of the response.

Treatment Targets in Inflammatory Bowel Disease: Current Status in Daily Practice.

Recently, treatment goals in inflammatory bowel disease (IBD) in clinical trials have shifted from mainly symptom-based to more mucosa-driven. Real world data on treatment priorities are lacking. We aimed to investigate the current practice and most commonly used definitions of IBD treatment targets among Dutch gastroenterologists. Dutch gastroenterologists were asked to participate in a computer-based nation-wide survey. We asked questions on demographics, opinion and current practice regarding IBD treatment targets. Twenty-four percent (134/556) of the respondents completed the survey. For both Crohn's disease (CD) (47.3%, 61/129) and ulcerative colitis (UC)(45%, 58/129) the main treatment goal was to achieve and maintain deep remission, defined as clinical, biochemical and endoscopic remission. Seventy-six percent of the participants use mucosal healing (MH) as a potential treatment target for IBD, whereas 22.6% use histological remission. There is no single definition for MH in IBD. The majority use Mayo score ≤ 1 in UC (52%) and 'macroscopic normal mucosa' in CD (66%). More stringent and mucosa-driven treatment targets as 'deep remission' and 'mucosal healing' have found traction in clinical practice. The most commonly used definition for MH in routine practice is endoscopic MAYO score </= 1 in UC and 'macroscopic normal mucosa' in CD.

Pivotal Role of Carbohydrate Sulfotransferase 15 in Fibrosis and Mucosal Healing in Mouse Colitis.

Induction of mucosal healing (MH) is an important treatment goal in inflammatory bowel disease (IBD). Although the molecular mechanisms underlying MH in IBD is not fully explored, local fibrosis would contribute to interfere mucosal repair. Carbohydrate sulfotransferase 15 (CHST15), which catalyzes sulfation of chondroitin sulfate to produce rare E-disaccharide units, is a novel mediator to create local fibrosis. Here we have used siRNA-based approach of silencing CHST15 in dextran sulfate sodium (DSS) induced colitis in mice, human colon fibroblasts and cancer cell lines. In a DSS-induced acute colitis model, CHST15 siRNA reduced CHST15 mRNA in the colon, serum IL-6, disease activity index (DAI) and accumulation of F4/80+ macrophages and ER-TR7+ fibroblasts, while increased Ki-67+ epithelial cells. In DSS-induced chronic colitis models, CHST15 siRNA reduced CHST15 mRNA in the colon, DAI, alpha-smooth muscle actin+ fibroblasts and collagen deposition, while enhanced MH as evidenced by reduced histological and endoscopic scores. We also found that endoscopic submucosal injection achieved effective pancolonic delivery of CHST15 siRNA in mice. In human CCD-18 Co cells, CHST15 siRNA inhibited the expression of CHST15 mRNA and selectively reduced E-units, a specific product biosynthesized by CHST15, in the culture supernatant. CHST15 siRNA significantly suppressed vimentin in both TGF-ß-stimulated CCD18-Co cells and HCT116 cells while up-regulated BMP7 and E-cadherin in HCT116 cells. The present study demonstrated that blockade CHST15 represses colonic fibrosis and enhances MH partly though reversing EMT pathway, illustrating a novel therapeutic opportunity to refractory and fibrotic lesions in IBD.

Faecal calprotectin: current usage and perceived beneficial effects of third-party funding on rates of colonoscopy by Australian gastroenterologists.

Studies have suggested a diagnostic role for faecal calprotectin (FC) in patients with gastroenterological disorders. To investigate Australian gastroenterologists' (GE) views on FC use and to elicit factors that affect physicians' choices. Electronic surveys were sent out to 405 consultants and 34 registrars in Australia. Respondents who answered <50% of the survey were excluded. In all, 140 participants provided a >50% response; 73% reported using FC in their clinical practice. Factors cited by non-users in restricting their FC use included cost (24%), availability (47%) and familiarity (18%). Even among users, 69% cited funding as a major deciding factor; 98 and 86% of FC users believed that the test is a reliable method of differentiating between inflammatory bowel disease (IBD) and irritable bowel syndrome (IBS) and assessing for mucosal healing in IBD respectively. Of non-users, 78 and 58%, respectively, would use FC to differentiate IBD from IBS and assess for mucosal healing in IBD, if FC testing was Medical Benefits Schedule (MBS) listed. Both users (79%) and non-users (68%) reported that use of FC to defer or avoid colonoscopies was likely if the test was MBS funded. Australian GE endorse the use of FC to discriminate between IBD and IBS, to check for mucosal healing in IBD and to reduce colonoscopy rates. Absence of MBS funding is an important factor contributing to the lack of usage of FC, in addition to the lack of familiarity with FC testing and availability.

Butyrate and Mucosal Inflammation: New Scientific Evidence Supports Clinical Observation

Butyrate and Mucosal Inflammation: New Scientific Evidence Supports Clinical Observation

Review article: newer optical and digital chromoendoscopy techniques vs. dye‐based chromoendoscopy for diagnosis and surveillance in inflammatory bowel disease

Recent innovations in gastrointestinal endoscopy have changed our traditional approach to diagnosis and therapy in patients with inflammatory bowel diseases (IBD). While traditionally used dye-based chromoendoscopy (DBC) techniques suffer from several limitations that reduce their utility in daily routine practice, newer 'dye-less' chromoendoscopy (DLC) techniques offer a great potential to overcome most of these limitations. To review available optical and digital chromoendoscopy techniques, by critically discussing their potential for diagnostic and surveillance colonoscopy in patients with IBD. A literature search on the use of dye-less and dye-based chromoendoscopy in IBD patients was performed. In long-standing IBD, DBC improves detection of dysplasia (diagnostic odds ratio = 17.5, 95% CI = 1.2-247.1) as well as prediction of inflammatory disease activity and extent of disease compared with standard video-colonoscopy. Narrow band imaging (NBI) shows no improvement in dysplasia detection rates compared with white-light endoscopy and DBC (P = 0.6). Moreover, NBI results in a suboptimal differentiation of dysplastic from nondysplastic lesions. No data regarding digital DLC techniques (i.e. FICE, i-scan) for dysplasia detection in IBD are yet available. Both NBI and i-scan are superior to white-light endoscopy in assessing the activity and extent of colorectal IBD. Although the potential benefits of newer optical and digital dye-less chromoendoscopy techniques over traditionally used DBC are substantial, only DBC can currently be recommended to improve dysplasia detection in long-standing IBD. In contrast, DLC has the potential to quantify disease activity and mucosal healing in IBD.

Naïve T cells correlate with mucosal healing in patients with inflammatory bowel disease

Background. In previous studies, adaptive immune responses involving T-helper cells have been shown to play an important role in inflammatory bowel diseases (IBDs). Methods. The aim of this study was to investigate any correlation between the degree of mucosal inflammation and the phenotype of gut-infiltrating T-helper cells. Biopsies from intestinal mucosa were obtained and intestinal T cells were analyzed with regard to activity and maturation markers. Patients with active colitis (39 with Crohn's disease and 47 with ulcerative colitis) were included and treated with corticosteroids, biologicals or leukocytapheresis. Flow cytometry was used to analyze activation marker expression on gut-infiltrating T-helper cells. Results. Mucosal healing was reflected by almost 100% increase of CD62L expression in mucosal T cells in patients in remission compared to those with active inflammation (p < 0.01). The frequency of mucosal-naïve CD4+CD45RA+ T cells was reduced by 50% in mucosa displaying remission (5.3% compared to 12% of the total amount and CD4+ T cells, p < 0.001). Surprisingly, the proportion of early activated T-helper cells (CD4+CD69+) did not differ between mucosa in remission and non-remission (43% and 42%, respectively). Moreover, no change in memory T-helper cells (CD4+CD45RO+) was observed (64% compared to 66%). The findings were independent of diagnosis (Crohn's disease or ulcerative colitis) or mode of treatment. Conclusion. This study suggests that a reduced recruitment of naïve T-helper cells and increased frequency of T-helper cells with lymph node homing marker expression reflect mucosal healing in IBD. Surprisingly, the degree of activation of mucosal T-helper cells did not correlate with disease remission.

Ghrelin ameliorates TNF-a induced anti-proliferative and pro-apoptotic effects and promotes intestinal epithelial restitution

Abstract Introduction: TNF-a is one of the major cytokine released by the invading mucosal leukocytes during acute exacerbations of inflammatory bowel disease (IBD). It interferes with the inherent restitutive potential of mucosal epithelial cells through inhibition of proliferation, cell migration and induction of cellular apoptosis. Ghrelin is a recently discovered peptide with mitogenic and anti-apoptotic properties. We hypothesized that ghrelin would modulate the TNF-a induced anti-proliferative, anti-migratory and pro-apoptotic effects to enhance mucosal healing in IBD. Methods: Non-transformed and transformed intestinal epithelial cell lines (FHs74Int, IEC-6 & Caco-2) were treated with TNF-a, ghrelin and ghrelin receptor antagonist in the presence or absence of specific cAMP, PI3K, EGFR, ERK1/2 inhibitors. Proliferation was determined by MTT assay, apoptosis by TUNEL staining and epithelial restitution by Podolsky's cell monolayer repair assay. Western blotting was employed to assess ghrelin's cytoprotective and prolifer ative role in the presence of TNF-a in relation to EGFR, PI3K/Akt, ERK1/2 pathways and caspase-3 profiling. Results: Ghrelin abrogates high dose TNF-alpha induced anti-proliferative and pro-apoptotic effects (p Conclusions: Ghrelin abolishes TNF-a induced anti-proliferative and pro-apoptotic effects and promotes intestinal epithelial restitutive behavior. Therapeutic utility of ghrelin in mucosal protection and regeneration in IBD warrants further investigation.