Superior bowel preparation quality for colonoscopy with 1L-PEG compared to 2L-PEG and picosulphate: Data from a large real-world retrospective outpatient cohort.

BACKGROUND: Several randomized clinical trials comparing different bowel preparations (BP) have shown similar efficacy; however, there is a lack of real-world studies on this topic. AIMS: This study aims to identify the most effective BP regimen in a real-world setting and any predictors of inadequate BP. METHODS: A retrospective single-center study was conducted over 14 months at an academic hospital including outpatient colonoscopies in which adult patients did not teach on how to perform BP before colonoscopy. Colonoscopies with 1L-PEG, 2L-PEG and picosulphate mixtures were considered. A multivariable analysis for factors associated to poor BP was fitted. RESULTS: Overall, 1779 patients (51 %F, 60±14) years were included. The 1L-PEG regimen provided a higher rate of BP adequacy at multivariate analysis (adjusted OR 2.30, 95 %CI 1.67-3.16,p < 0.001) and was associated with higher median Boston Bowel Preparation Scale score (p < 0.001), higher rate of right-colon cleansing (p < 0.001) and exam completion (p = 0.04). Furthermore, we identified male sex, history of constipation, active smoking, previous pelvic surgery, concomitant psychiatric/neurological or chronic kidney diseases as predictors of inadequate BP. CONCLUSIONS: This is the largest real-world study comparing 1L-PEG to other BP regimens. Our results suggest 1L-PEG provides better BP in a non-controlled setting, improving clinical practice quality and minimizing the need for repeated colonoscopies and saving healthcare resources.

Gastric Carcinoma in Autoimmune Gastritis: A Histopathologic and Molecular Study.

Patients with autoimmune gastritis (AIG) have a 13-fold risk of developing type-1 neuroendocrine tumors, whereas the risk for gastric adenocarcinoma is still uncertain. Here we describe the clinicopathologic and molecular features of a series of gastric carcinomas (GC) arising in the context of AIG. A total of 26 AIG-associated GC specimens were collected from 4 Italian Institutions. Immunohistochemistry for MUC1, MUC2, MUC5AC, MUC6, CDX2, HER2, PD-L1, CLDN18, mismatch repair (MMR) proteins, and p53 and EBV-encoded RNA (EBER) in situ hybridization were performed. Histologic and immunohistochemical features were jointly reviewed by 5 expert gastrointestinal pathologists. Next-generation sequencing analysis (TrueSight Oncology 500, Illumina) of 523 cancer-related genes was performed on 19 cases. Most tumors were diagnosed as pT1 (52%) and they were located in the corpus/fundus (58%) and associated with operative link for gastritis assessment stage II gastritis (80.8%), absence of parietal cells, complete intestinal metaplasia, and enterochromaffin-like-cell micronodular hyperplasia. Only 4 (15.4%) GCs were diagnosed during follow-up for AIG. The following histotypes were identified: 20 (77%) adenocarcinomas; 3 (11%) mixed neuroendocrine-non-neuroendocrine neoplasms, and 2 (8%) high-grade solid adenocarcinomas with focal neuroendocrine component, 1 (4%) adenocarcinoma with an amphicrine component. Overall, 7 cases (27%) showed MMR deficiency, 3 (12%) were positive (score 3+) for HER2, 6 (23%) were CLDN18 positive, and 11 (42%) had PD-L1 combined positive score ≥ 10. EBER was negative in all cases. Molecular analysis revealed 5/19 (26%) microsatellite instability (MSI) cases and 7 (37%) tumor mutational burden (TMB) high. The most frequently altered genes were TP53 (8/19, 42%), RNF43 (7/19, 37%), ERBB2 (7/19, 37% [2 amplified and 5 mutated cases]), ARID1A (6/19, 32%), and PIK3CA (4/19, 21%). In summary, AIG-associated GCs are often diagnosed at low stage in patients with longstanding misrecognized severe AIG; they often display a neuroendocrine component or differentiation, have relatively higher rates of MMR deficiency, and TMB high.

A Comprehensive Review on Bariatric Endoscopy: Where We Are Now and Where We Are Going.

Background: Obesity is a chronic disease that impairs quality of life and leads to several comorbidities. When conservative therapies fail, bariatric surgical options such as Roux-en-Y gastric bypass (RYGB) and sleeve gastrectomy (SG) are the most effective therapies to induce persistent weight loss. Over the last two decades, bariatric endoscopy has become a valid alternative to surgery in specific settings. Primary bariatric endoscopic therapies: Restrictive gastric procedures, such as intragastric balloons (IGBs) and endoscopic gastroplasty, have been shown to be effective in inducing weight loss compared to diet modifications alone. Endoscopic gastroplasty is usually superior to IGBs in maintaining weight loss in the long-term period, whereas IGBs have an established role as a bridge-to-surgery approach in severely obese patients. IGBs in a minority of patients could be poorly tolerated and require early removal. More recently, novel endoscopic systems have been developed with the combined purpose of inducing weight loss and improving metabolic conditions. Duodenal mucosal resurfacing demonstrated efficacy in this field in its early trials: significant reduction from baseline of HbA1c values and a modest reduction of body weight were observed. Other endoscopic malabsorptive have been developed but need more evidence. For example, a pivotal trial on duodenojejunal bypasses was stopped due to the high rate of severe adverse events (hepatic abscesses). Optimization of these more recent malabsorptive endoscopic procedures could expand the plethora of bariatric patients that could be treated with the intention of improving their metabolic conditions. Revisional bariatric therapies: Weight regain may occur in up to one third of patients after bariatric surgery. Different endoscopic procedures are currently performed after both RYGB and SG in order to modulate post-surgical anatomy. The application of argon plasma coagulation associated with endoscopic full-thickness suturing systems (APC-TORe) and Re-EndoSleeve have shown to be the most effective endoscopic treatments after RYGB and SG, respectively. Both procedures are usually well tolerated and have a very low risk of stricture. However, APC-TORe may sometimes require more than one session to obtain adequate final results. The aim of this review is to explore all the currently available primary and revisional endoscopic bariatric therapies focusing on their efficacy and safety and their potential application in clinical practice.

Mucosal Overexpression of Thymic Stromal Lymphopoietin and Proinflammatory Cytokines in Patients With Autoimmune Atrophic Gastritis.

INTRODUCTION: The immune mechanisms underlying human autoimmune atrophic gastritis (AAG) are poorly understood. We sought to assess immune mucosal alterations in patients with AAG. METHODS: In 2017-2021, we collected gastric corpus biopsies from 24 patients with AAG (median age 62 years, interquartile range 56-67, 14 women), 26 age-matched and sex-matched healthy controls (HCs), and 14 patients with Helicobacter pylori infection (HP). We investigated the lamina propria mononuclear cell (LPMC) populations and the mucosal expression of thymic stromal lymphopoietin (TSLP) and nicotinamide phosphoribosyltransferase (NAMPT). Ex vivo cytokine production by organ culture biopsies, under different stimuli (short TSLP and zinc-l-carnosine), and the gastric vascular barrier through plasmalemma vesicle-associated protein-1 (PV1) were also assessed. RESULTS: In the subset of CD19+ LPMC, CD38+ cells (plasma cells) were significantly higher in AAG compared with HC. Ex vivo production of tumor necrosis factor (TNF)-α, interleukin (IL)-15, and transforming growth factor ß1 was significantly higher in AAG compared with HC. At immunofluorescence, both IL-7R and TSLP were more expressed in AAG compared with HC and HP, and short TSLP transcripts were significantly increased in AAG compared with HC. In the supernatants of AAG corpus mucosa, short TSLP significantly reduced TNF-α, while zinc-l-carnosine significantly reduced interferon-γ, TNF-α, IL-21, IL-6, and IL-15. NAMPT transcripts were significantly increased in AAG compared with HC. PV1 was almost absent in AAG, mildly expressed in HC, and overexpressed in HP. DISCUSSION: Plasma cells, proinflammatory cytokines, and altered gastric vascular barrier may play a major role in AAG. TSLP and NAMPT may represent potential therapeutic targets, while zinc-l-carnosine may dampen mucosal inflammation.

Histologic heterogeneity and syndromic associations of non-ampullary duodenal polyps and superficial mucosal lesions.

BACKGROUND: Duodenal polyps and superficial mucosal lesions (DP/SMLs) are poorly characterised. AIMS: To describe a series of endoscopically-diagnosed extra-ampullary DPs/SMLs. METHODS: This is a retrospective study conducted in a tertiary referral Endoscopy Unit, including patients who had DPs or SMLs that were biopsied or removed in 2010-2019. Age, gender, history of familial polyposis syndromes, DP/SML characteristics were recorded. Histopathological, immunohistochemical and molecular analyses were performed. RESULTS: 399 non-ampullary DP/SMLs from 345 patients (60.6% males; median age 67 years) were identified. Gastric foveolar metaplasia represented the most frequent histotype (193 cases, 48.4%), followed by duodenal adenomas (DAs; 77 cases, 19.3%). Most DAs (median size 6 mm) were sessile (Paris Is; 48%), intestinal-type (96.1%) with low-grade dysplasia (93.5%). Among syndromic DAs (23%), 15 lesions occurred in familial adenomatous polyposis 1, two were in MUTYH-associated polyposis and one was in Peutz-Jeghers syndrome (foveolar-type, p53-positive, low-grade dysplasia). Only one (3.3%) tubular, low-grade DA showed mismatch repair deficiency (combined loss of MLH1 and PMS2, heterogeneous MSH6 expression), and it was associated with a MLH1 gene germline mutation (Lynch syndrome). CONCLUSION: DPs/SMLs are heterogeneous lesions, most of which showing foveolar metaplasia, followed by low-grade, intestinal-type, non-syndromic DAs. MMR-d testing may identify cases associated with Lynch syndrome.

Incidence and risk factors for preneoplastic and neoplastic lesions of the colon and rectum in patients under 50 referred for colonoscopy.

BACKGROUND: Colorectal cancer (CRC) diagnosed before the age of 50, known as early-onset CRC (eoCRC), is considered uncommon. We aimed at analysing the incidence of preneoplastic and neoplastic lesions of the colon and rectum in patients under 50 years old and to identify possible predictors Methods: We retrospectively collected data from 1778 patients under 50 years old (mean age 39.9±7.8) referred for colonoscopy between 2015-2018. Cumulative incidence of adenomas and eoCRC was assessed. Multivariable regression models were fitted Results: The cumulative incidence for adenomas was 11.0% (95% CI 9-12), while it was 1.5% (95% CI 1-2) for eoCRC (metastatic disease in 13/27 patients). Age as a continuous variable was associated with the presence of adenomas (incidence rate ratio 1.06; 95% CI 1.03-1.09; p<0.001). EoCRC arose in most cases in the rectum (13/27, 48.1%). Age ≥40 was the main risk factor (OR 2.25; 95% CI 1.35-3.73; p=0.002) for both adenomas (160/196 patients, 81.6%) and eoCRC (20/27 patients, 74.1%), while smoking seemed to have no role (p=0.772). The presence of alarm symptoms was statistically significant at bivariable analysis for eoCRC only (OR 3.70; 95% CI 1.49-9.22; p=0.005), as well as having multiple gastrointestinal symptoms (OR 19.85; 95% CI 2.64-149.42; p=0.004). Only 3/27 (11.1%) patients with eoCRC had a family history for CRC Conclusions: A high cumulative incidence rate of both adenomas and eoCRC was found, this latter occurring more common in patients aged 40-49, without apparent risk factors. The presence of alarm symptoms or multiple gastrointestinal symptoms led to a late diagnosis.

Epstein-Barr virus negative smooth muscle neoplasm of the stomach in a young woman.

Gastric smooth muscle neoplasms are rare and poorly investigated malignancies. Their importance relies on differential diagnosis with more frequent neoplasms(e.g. GIST), on their often mild and deceitful clinical presentation and on their heterogeneous outcome. Moreover, the pathogenesis of gastric leiomyosarcoma seems to point to some acknowledged oncogenic factors such as radiations or oncogenic viral infections. Herein, we describe a case of metastatic gastric leiomyosarcoma in a young woman, previously diagnosed with acute lymphoblastic leukemia treated with chemoradiotherapy.

Upper gastrointestinal bleeding in COVID-19 inpatients: Incidence and management in a multicenter experience from Northern Italy.

BACKGROUND: COVID-19 patients have an increased susceptibility to develop thrombotic complications, thus thromboprophylaxis is warranted which may increase risk of upper gastrointestinal bleeding (UGIB). Our aim was to evaluate incidence of UGIB and use of upper GI endoscopy in COVID-19 inpatients. METHODS: The medical and endoscopic management of UGIB in non-ICU COVID-19 patients has been retrospectively evaluated. Glasgow Blatchford score was calculated at onset of signs of GI bleeding. Timing between onset of signs of GI bleeding and execution, if performed, of upper GI endoscopy was evaluated. Endoscopic characteristics and outcome of patients were evaluated overall or according to the execution or not of an upper GI endoscopy before and after 24h. RESULTS: Out of 4871 COVID-19 positive patients, 23 presented signs of UGIB and were included in the study (incidence 0.47%). The majority (78%) were on anticoagulant therapy or thromboprophylaxis. In 11 patients (48%) upper GI endoscopy was performed within 24h, whereas it was not performed in 5. Peptic ulcer was the most common finding (8/18). Mortality rate was 21.7% for worsening of COVID-19 infection. Mortality and rebleeding were not different between patients having upper GI endoscopy before or after 24h/not performed. Glasgow Blatchford score was similar between the two groups (13;12-16 vs 12;9-15). CONCLUSION: Upper GI bleeding complicated hospital stay in almost 0.5% of COVID-19 patients and peptic ulcer disease is the most common finding. Conservative management could be an option in patients that are at high risk of respiratory complications.

Safety and durability of PEG-J: a single-centre experience.

INTRODUCTION: Although percutaneous endoscopic gastrostomy with jejunal extension (PEG-J) is currently indicated in a variety of conditions, limited data are available regarding its safety and the best timing for its replacement. We herein describe a single-centre cohort of patients who underwent PEG-J placement or replacement to assess the short- and long-term safety of the procedure. METHODS: Demographic and procedure-related data regarding all patients undergoing a PEG-J procedure between March 2010 and 2020, either first placement or any replacement, at the Endoscopy Unit of a University Hospital in Northern Italy (IRCCS Policlinico San Matteo, Pavia, Italy), were retrospectively collected. Data were collected until last available follow-up. RESULTS: We included 73 patients (mean age 70 ± 9.7, 60.3% female) who underwent a PEG-J procedure. Data on a total of 215 procedures were gathered with a median follow up time of 21 months (IQR 9.3-39.5). No immediate adverse events (AEs) were reported. Short-term (within 30 days) AEs, including jejunal extension dislocations, accidental removal, obstruction and kinking occurred in 12 patients (5.6% of the total procedures), whilst long-term AEs (obstruction, tube malfunctions, inner tube dislocation, pyloric ulcer, hypergranulation tissue, wear, buried bumper syndrome and accidental removal) were reported in 40 patients. The risk of developing an AE was not reduced if tube replacement was performed electively. The median duration of the PEG-J before replacement was 12 months (IQR 6-16 months). CONCLUSION: PEG-J placement and replacement are safe procedures. Although PEG-J durability is variable an elective procedure might be indicated to reduce urgent replacements.

Proteolytic cleavage and loss of function of biologic agents that neutralize tumor necrosis factor in the mucosa of patients with inflammatory bowel disease.

BACKGROUND & AIMS: Many patients with inflammatory bowel disease (IBD) fail to respond to anti-tumor necrosis factor (TNF) agents such as infliximab and adalimumab, and etanercept is not effective for treatment of Crohn's disease. Activated matrix metalloproteinase 3 (MMP3) and MMP12, which are increased in inflamed mucosa of patients with IBD, have a wide range of substrates, including IgG1. TNF-neutralizing agents act in inflamed tissues; we investigated the effects of MMP3, MMP12, and mucosal proteins from IBD patients on these drugs. METHODS: Biopsy specimens from inflamed colon of 8 patients with Crohn's disease and 8 patients with ulcerative colitis, and from normal colon of 8 healthy individuals (controls), were analyzed histologically, or homogenized and proteins were extracted. We also analyzed sera from 29 patients with active Crohn's disease and 33 patients with active ulcerative colitis who were candidates to receive infliximab treatment. Infliximab, adalimumab, and etanercept were incubated with mucosal homogenates from patients with IBD or activated recombinant human MMP3 or MMP12 and analyzed on immunoblots or in luciferase reporter assays designed to measure TNF activity. IgG cleaved by MMP3 or MMP12 and antihinge autoantibodies against neo-epitopes on cleaved IgG were measured in sera from IBD patients who subsequently responded (clinical remission and complete mucosal healing) or did not respond to infliximab. RESULTS: MMP3 and MMP12 cleaved infliximab, adalimumab, and etanercept, releasing a 32-kilodalton Fc monomer. After MMP degradation, infliximab and adalimumab functioned as F(ab')2 fragments, whereas cleaved etanercept lost its ability to neutralize TNF. Proteins from the mucosa of patients with IBD reduced the integrity and function of infliximab, adalimumab, and etanercept. TNF-neutralizing function was restored after incubation of the drugs with MMP inhibitors. Serum levels of endogenous IgG cleaved by MMP3 and MMP12, and antihinge autoantibodies against neo-epitopes of cleaved IgG, were higher in patients who did not respond to treatment vs responders. CONCLUSIONS: Proteolytic degradation may contribute to the nonresponsiveness of patients with IBD to anti-TNF agents.

Absence of a role for interleukin-13 in inflammatory bowel disease.

IL-13 has been implicated in the pathogenesis of ulcerative colitis (UC), and may have a role in animal models of gut fibrosis. We studied the involvement of IL-13 in inflammation and fibrosis in UC and Crohn's disease (CD). Intestinal biopsies and anti-CD3/CD28- or anti-CD2/CD28-stimulated lamina propria mononuclear cells from UC and CD patients and control subjects were cultured, and IL-13, IL-4, IL-5, IL-17A and IFN-γ production was measured. Mucosal IL-13-producing cells were characterised by flow cytometry. Gut explants from strictured CD, non-strictured CD and healthy donors were cultured ex vivo, and secreted IL-13, IL-1ß and collagen were measured. IL-13 production by mucosal explants and activated lamina propria mononuclear cells did not differ between CD, UC and control subjects, and was at least a log lower than IFN-γ and IL-17A. IL-13-producing cells, and in particular natural killer T cells, were uniformly low in all groups. IL-4 and IL-5 were undetectable in culture supernatants. Explants of CD strictures produced low amounts of IL-13, whereas IL-1ß and collagen were elevated. We could not confirm that UC or strictured CD are associated with elevated IL-13 production. These data suggest that an anti-IL-13 Ab would not be an appropriate therapeutic strategy in inflammatory bowel disease.

Effect of tumor necrosis factor-α blockade on mucosal addressin cell-adhesion molecule-1 in Crohn's disease.

BACKGROUND: Mucosal addressin cell-adhesion molecule (MAdCAM)-1, which is overexpressed on gut endothelium in active Crohn's disease (CD), promotes intestinal recruitment of integrin α(4)ß(7)(*) T cells that sustain chronic inflammation. As tumor necrosis factor alpha (TNF)-α, a cytokine centrally involved in CD, modulates gut endothelial adhesion molecules, we here explored the in vivo and ex vivo effects of TNF-α blockade on MAdCAM-1 expression in CD. METHODS: MAdCAM-1 was determined by immunoblotting in colonic biopsies collected before and 10 weeks after either infliximab or adalimumab treatment in CD patients, and in CD biopsies incubated with either infliximab or adalimumab or control IgG(1). Integrin ß(7)(*) circulating T cells were analyzed by flow cytometry. RESULTS: MAdCAM-1 significantly decreased after either infliximab or adalimumab treatment in responder but not in nonresponder patients. In parallel, an increase of circulating ß(7)(*) T cells was found in responder patients only. A marked downregulation of MAdCAM-1 was observed in CD biopsies cultured with either infliximab or adalimumab in comparison to IgG(1)-treated biopsies. CONCLUSIONS: Our findings showing that MAdCAM-1 is downregulated by TNF-α blockade point to a novel mechanism of action of anti-TNF-α antibodies in CD.

Recent advances in understanding Crohn's disease.

Crohn's disease is a chronic inflammatory bowel disorder resulting from an inappropriate innate and acquired immune response to commensal microorganisms in genetically susceptible individuals. This disease has a fluctuating course, with alternating periods of remission and relapses, and it is characterized by a remarkable clinical heterogeneity; it may be complicated by perianal fistulas, abscesses, and intestinal strictures leading to obstructions, besides several systemic manifestations. However, a complete resolution of the disease is currently not possible, yet Crohn's disease can be managed with established and novel therapies, which achieve long-term remission and acceptable quality of life. This review is focused on novel advances in basic and clinical aspects of Crohn's disease, although it also deals with new trends in diagnosis and treatment.

Recent advances in understanding ulcerative colitis.

Ulcerative colitis, one of the two main forms of inflammatory bowel disease, is characterized by inflammation of the large bowel with constant involvement of the rectum, and a possible continuous retrograde distribution up to the cecum. Typical macroscopic lesions are mucosal ulcerations, with immune cell infiltration and cryptic abscesses at histology. Ulcerative colitis usually manifests with bloody diarrhea, is associated with a number of extra-intestinal manifestations, and may be acutely complicated by toxic megacolon. Longstanding disease may predispose to the development of colorectal cancer. Therapeutic options include mesalazine, corticosteroids, immunomodulators and biologic agents; however, if these treatments fail, the only available therapeutic choice remaining is the surgical removal of the colon. This review emphasizes novel concepts in the basic aspects of ulcerative colitis, and, in addition to the current clinical and diagnostic knowledge, it also describes new treatment options for this condition.

New pathogenic paradigms in inflammatory bowel disease.

Recent progresses in basic science have opened new pathogenic scenarios in inflammatory bowel disease. The T helper cell type (Th)1/Th2 paradigm has been outdated thanks to the advances in understanding the function of Th17 cells. Innate immunity, nonimmune cells, and defective tolerogenic mechanisms play a no less crucial role than do adaptive immunity, immune cells, and hyperactivation of effector mechanisms. These new paradigms, together with the no longer "static" but "dynamic" vision of intestinal inflammation, highlight new possible therapeutic targets in inflammatory bowel disease.

Involvement of CD40-CD40 ligand in uncomplicated and refractory celiac disease.

OBJECTIVES: Cognate interaction between CD40 on antigen-presenting cells and CD40 ligand (CD40L) on T cells is a crucial costimulatory signal in T-cell activation. In this study, we investigated CD40-CD40L expression in the duodenum of uncomplicated and refractory celiac disease patients, and explored the ex vivo effects of CD40L blockade on cytokine production and the T-helper cell type 1-specific transcription factor T-bet. METHODS: CD40L and colocalization of CD40 with the dendritic cell markers CD11c and CD123 were investigated by confocal microscopy on tissue sections of duodenal biopsy samples obtained from 14 uncomplicated celiac patients before and after 12 months of gluten-free diet, 5 refractory celiac patients, and 12 controls. CD40 was also analyzed by flow cytometry on single cell suspension of mucosal biopsies. Treated celiac biopsies were stimulated with peptic-tryptic digest of gliadin (PT-gliadin) with or without an anti-CD40L-neutralizing antibody. Interferon (IFN)-γ and interleukin (IL)-17 were measured by ELISA (enzyme-linked immunosorbent assay). T-bet, CD40, and CD40L were determined by immunoblotting. RESULTS: CD40 and CD40L expression was higher in uncomplicated untreated and refractory celiac patients than in controls; the expression returned to normal after gluten-free diet in uncomplicated patients. Flow cytometric analysis confirmed that most CD40(+) cells were dendritic cells. The addition of the anti-CD40L antibody to treated celiac biopsies significantly inhibited the PT-gliadin-induced production of IFN-γ and IL-17, and mucosal T-bet. CONCLUSIONS: Our results indicate that the CD40-CD40L pathway has a key role in celiac disease. Disruption of CD40-CD40L interaction may offer a therapeutic alternative in refractory celiac disease.

Peripheral regulatory T cells and serum transforming growth factor-ß: relationship with clinical response to infliximab in Crohn's disease.

BACKGROUND: CD4(+)Foxp3(+) regulatory T cells (Treg) inhibit T-cell proliferation in vitro and are effective in suppressing colitis in mouse models. Tumor necrosis factor (TNF)-α, which is centrally involved in Crohn's disease (CD) pathogenesis, also impairs Treg function. Here we investigated the influence of anti-TNF therapy on Treg frequency and function in CD. METHODS: Twenty CD patients were treated with infliximab administered at weeks 0, 2, and 6. Blood was collected immediately before the first infusion and after 10 weeks. Treg frequency was quantified by flow cytometry. Treg function was measured using a standard coculture assay. Serum levels of transforming growth factor (TGF)-ß1 and interleukin (IL)-10 were measured by enzyme-linked immunosorbent assay (ELISA). RESULTS: Pretreatment Treg frequency and serum TGF-ß1 levels were significantly higher in nonresponder than responder patients. Clinical improvement in 12 CD patients was associated with a significant increase of Treg frequency after 10 weeks. Treg were functionally active before and after treatment with infliximab, both in responder and nonresponder CD patients. In responder patients the restoration of Treg pool was accompanied by a parallel significant increase of serum TGF-ß1 and IL-10. No significant change in the elevated Treg or serum TGF-ß1 was seen in nonresponder patients. CONCLUSIONS: This study suggests that there may be a relationship between numbers of Treg in the blood, serum TGF-ß1, and response to infliximab; however, further prospective studies are needed.

Targeting gut T cell Ca2+ release-activated Ca2+ channels inhibits T cell cytokine production and T-box transcription factor T-bet in inflammatory bowel disease.

Prolonged Ca(2+) entry through Ca(2+) release-activated Ca(2+) (CRAC) channels is crucial in activating the Ca(2+)-sensitive transcription factor NFAT, which is responsible for directing T cell proliferation and cytokine gene expression. To establish whether targeting CRAC might counteract intestinal inflammation, we evaluated the in vitro effect of a selective CRAC inhibitor on T cell cytokine production and T-bet expression by lamina propria mononuclear cells (LPMC) and biopsy specimens from inflammatory bowel disease (IBD) patients. The inhibitory activity of the CRAC blocker was investigated through patch-clamp experiments on rat basophilic leukemia cells and fluorometric imaging plate reader intracellular Ca(2+) assays using thapsigargin-stimulated Jurkat T cells and its detailed selectivity profile defined using a range of in vitro radioligand binding and functional assays. Anti-CD3/CD28-stimulated LPMC and biopsy specimens from 51 patients with IBD were cultured with a range of CRAC inhibitor concentrations (0.01-10 microM). IFN-gamma, IL-2, IL-8, and IL-17 were analyzed by ELISA. T-bet was determined by immunoblotting. We found that the CRAC blocker concentration-dependently inhibited CRAC current in rat basophilic leukemia cells and thapsigargin-induced Ca(2+) influx in Jurkat T cells. A concentration-dependent reduction in T-bet expression and production of IFN-gamma, IL-2, IL-17, but not IL-8, was observed in IBD LPMC and biopsy specimens treated with the CRAC inhibitor. In conclusion, we provide evidence that the suppression of CRAC channel function may dampen the increased T cell response in the inflamed gut, thus suggesting a promising role for CRAC inhibitor drugs in the therapeutic management of patients with IBD.