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Hypopharyngeal multichannel intraluminal impedance-pH (HMII-pH) technology incorporating 2 trans-upper esophageal sphincter impedance channels has been developed to detect pharyngeal reflux. We used the HMII-pH technique to validate the candidate pharyngeal acid reflux (PAR) episodes based on the dual-pH tracings and determined the interobserver reproducibility.We conducted a cross-sectional study in tertiary centers in Taiwan. Ninety patients with suspected laryngopharyngeal reflux and 28 healthy volunteers underwent HMII-pH test when off acid suppressants. Candidate PAR episodes were characterized by pharyngeal pH drops of at least 2 units and reaching a nadir pH of 5 within 30 seconds during esophageal acidification. Two experts manually independently identified candidate PAR episodes based on the dual-pH tracings. By reviewing the HMII-pH tracings, HMII-pH-proven PAR episodes were subsequently confirmed. The consensus reviews of HMII-pH-proven PAR episodes were considered to be the reference standard diagnosis. The interobserver reproducibility was assessed.A total of 105 candidate PAR episodes were identified. Among them 84 (80.0%; 95% CI, 71.0-87.0%) were HMII-pH-proven PAR episodes (82 in 16 patients and 2 in 1 healthy subject). Patients tended to have more HMII-pH-proven PAR episodes than healthy controls (median and percentile values [25th, 75th, and 95th percentiles]: 0 [0, 0, 3] vs 0 [0, 0, 0],Our preliminary data showed that 80.0% (71.0-87.0%) of the proposed candidate PAR episodes were HMII-pH-proven PAR episodes, among which the interobserver reproducibility was good.

Ulcerative Colitis (UC) is a chronic gastrointestinal condition with high morbidity. While modern medical therapies have revolutionized the care of UC, 10-25% of patients fail medications and still progress to surgery. Thus, developing new treatments is a core problem in UC. T-cells, especially Th17 cells, are strongly linked with UC and are major targets of medications in UC. Tissue-resident memory T-cells (TRM) are a distinct class of T-cells that are highly enriched in the intestine, closely aligned with the microbiota, and are implicated in the pathogenesis of UC. Unlike circulating T-cells, TRMare difficult to target because they do not recirculate. Thus, we focused on cytokines like IL-15 which act as a tissue danger signal and regulate T-cellsin situ. We found that theIL15axis is upregulated in UC and predicts treatment response. IL-15 was redundant for Th17 differentiation but could activate terminally differentiated Th17 cells to promote intestinal inflammation. Finally, in CD4+TRMfrom patients with UC, IL-15 upregulatedRORC, the master transcription factor for Th17 cells, via a Janus Kinase (JAK)1 pathway. Thus, IL-15 promotes terminally differentiated inflammatory Th17 cells in the intestine raising the possibility that IL-15 may be a target for UC treatments.

Intestinal IL-17-producing T helper (Th17) cells are dependent on adherent microbes in the gut for their development. However, how microbial adherence to intestinal epithelial cells (IECs) promotes Th17 cell differentiation remains enigmatic. Here, we found that Th17 cell-inducing gut bacteria generated an unfolded protein response (UPR) in IECs. Furthermore, subtilase cytotoxin expression or genetic removal of X-box binding protein 1 (Xbp1) in IECs caused a UPR and increased Th17 cells, even in antibiotic-treated or germ-free conditions. Mechanistically, UPR activation in IECs enhanced their production of both reactive oxygen species (ROS) and purine metabolites. Treating mice with N-acetyl-cysteine or allopurinol to reduce ROS production and xanthine, respectively, decreased Th17 cells that were associated with an elevated UPR. Th17-related genes also correlated with ER stress and the UPR in humans with inflammatory bowel disease. Overall, we identify a mechanism of intestinal Th17 cell differentiation that emerges from an IEC-associated UPR.

Background & Aims CD4+ T cells are regulated by activating and inhibitory cues, and dysregulation of these proper regulatory inputs predisposes these cells to aberrant inflammation and exacerbation of disease. We investigated the role of the inhibitory receptor paired immunoglobulin-like receptor B (PIR-B) in the regulation of the CD4+ T-cell inflammatory response and exacerbation of the colitic phenotype. Methods We used Il10-/- spontaneous and CD4+CD45RBhi T-cell transfer models of colitis with PIR-B-deficient (Pirb-/-) mice. Flow cytometry, Western blot, and RNA sequencing analysis was performed on wild-type and Pirb-/- CD4+ T cells. In silico analyses were performed on RNA sequencing data set of ileal biopsy samples from pediatric CD and non–inflammatory bowel disease patients and sorted human memory CD4+ T cells. Results We identified PIR-B expression on memory CD4+ interleukin (IL)17a+ cells. We show that PIR-B regulates CD4+ T-helper 17 cell (Th17)-dependent chronic intestinal inflammatory responses and the development of colitis. Mechanistically, we show that the PIR-B– Src-homology region 2 domain-containing phosphatase-1/2 axis tempers mammalian target of rapamycin complex 1 signaling and mammalian target of rapamycin complex 1–dependent caspase-3/7 apoptosis, resulting in CD4+ IL17a+ cell survival. In silico analyses showed enrichment of transcriptional signatures for Th17 cells (RORC, RORA, and IL17A) and tissue resident memory (HOBIT, IL7R, and BLIMP1) networks in PIR-B+ murine CD4+ T cells and human CD4+ T cells that express the human homologue leukocyte immunoglobulin-like receptor subfamily B member 3 (LILRB3). High levels of LILRB3 expression were associated strongly with mucosal injury and a proinflammatory Th17 signature, and this signature was restricted to a treatment-naïve, severe pediatric CD population. Conclusions Our findings show an intrinsic role for PIR-B/LILRB3 in the regulation of CD4+ IL17a+ T-cell pathogenic memory responses., Graphical abstract

Global warming is a great threat to life on our planet. Health care systems are high resource utilizers and contribute significantly to the problem. However, we can also be part of the solution as endoscopy services are the second waste producer in a hospital. Green endoscopy is a concept of implementing efficient strategies to minimize waste and to optimize utilization of equipment and supplies to maximize the benefits for the patient, the hospital, and our community. This manuscript aims to educate us on the problem and the cost to all of us as a whole and put into context the important part that endoscopic services have in energy utilization and waste generation. Finally, we suggest strategies, some low cost and high impacts, such as appropriate waste classification and disposal, some higher cost and high impact, such as water recycling and management as well as natural and LED lighting. We hope that we can generate enough momentum and enhance the discussion at the local, regional, national, and international levels about this challenge facing us and how we can be a unified force for positive change.

The involvement of host immunity in the gut microbiota-mediated colonization resistance to Clostridioides difficile infection (CDI) is incompletely understood. Here, we show that interleukin (IL)-22, induced by colonization of the gut microbiota, is crucial for the prevention of CDI in human microbiota-associated (HMA) mice. IL-22 signaling in HMA mice regulated host glycosylation, which enabled the growth of succinate-consuming bacteria Phascolarctobacterium spp. within the gut microbiome. Phascolarctobacterium reduced the availability of luminal succinate, a crucial metabolite for the growth of C. difficile, and therefore prevented the growth of C. difficile. IL-22-mediated host N-glycosylation is likely impaired in patients with ulcerative colitis (UC), and renders UC-HMA mice more susceptible to CDI. Transplantation of healthy human-derived microbiotas or Phascolarctobacterium reduced luminal succinate levels and restored colonization resistance in UC-HMA mice. IL-22-mediated host glycosylation thus fosters the growth of commensal bacteria that compete with C. difficile for the nutritional niche.

The formation of Ca

BACKGROUND & AIMS: Helicobacter pylori induces immune tolerance and is associated with a lower risk for immune-mediated disorders, such as autoimmune and inflammatory bowel diseases (IBD). We aimed to determine the effects of treatment for H pylori infection on the incidence of autoimmune disease and IBD. METHODS: We collected data from the National Health Insurance Research Database in Taiwan on patients younger than 18 years old without a prior diagnosis of autoimmune disease or IBD. Patients with peptic ulcer disease (PUD) with treatment of H pylori infection (PUD+HPRx), PUD without H pylori treatment (PUD–HPRx), a urinary tract infection (UTI) treated with cephalosporin, or without PUD (controls) were matched for age, sex, insurance, and Charlson’s comorbidity index score. RESULTS: Of the 1 million patients we collected data from in 2005, we included 79,181 patients in the study. We compared the effects of treatment for H pylori infection on the risk of autoimmunity or IBD and found that PUD+HPRx has the highest adjusted hazard risk (aHR) for autoimmunity or IBD (aHR, 2.36), compared to PUD–HPRx (aHR, 1.91) or UTI (aHRs, 1.71) (P

Pathobionts employ unique metabolic adaptation mechanisms to maximize their growth in disease conditions. Adherent–invasive Escherichia coli (AIEC), a pathobiont enriched in the gut mucosa of patients with inflammatory bowel disease (IBD), utilizes diet-derived L-serine to adapt to the inflamed gut. Therefore, the restriction of dietary L-serine starves AIEC and limits its fitness advantage. Here, we find that AIEC can overcome this nutrient limitation by switching the nutrient source from the diet to the host cells in the presence of mucolytic bacteria. During diet-derived L-serine restriction, the mucolytic symbiont Akkermansia muciniphila promotes the encroachment of AIEC to the epithelial niche by degrading the mucus layer. In the epithelial niche, AIEC acquires L-serine from the colonic epithelium and thus proliferates. Our work suggests that the indirect metabolic network between pathobionts and commensal symbionts enables pathobionts to overcome nutritional restriction and thrive in the gut.

Background Helicobacter pylori infection is known to decrease the incidences of autoimmune diseases and inflammatory bowel disease(IBD). Our aim was investigating the effect of H. pylori treatment in diabetes mellitus(DM) patients. Methods Adults with newly-diagnosed H. pylori infection or peptic ulcer disease(PUD) within the general population and DM population were identified from the National Health Insurance Research Database of Taiwan from 2000–2010. 79,181 patients were assigned to the 3 groups: general population with PUD without H. pylori treatment(PUD-HPRx in general population), DM patients with PUD without H. pylori treatment(PUD-HPRx in DM), and DM patients with PUD who received H. pylori treatment(PUD+HPRx in DM). Results Higher incidences of autoimmune diseases and IBD were observed in the PUD+HPRx in DM group than in the PUD-HPRx in general population and PUD-HPRx in DM groups (autoimmune diseases = 5.14% vs 3.47% and 3.65%; IBD = 5.60% vs 3.17% and 3.25%; P Conclusions The results revealed that H. pylori treatment increased the incidences of autoimmune diseases and IBD and decreased the all-cause mortality in the DM group with PUD. The effect was more significant in younger patients. This finding assists in realizing the influence of H. pylori treatment in the DM population.

Background The Maastricht V/Florence Consensus Report recommends amoxicillin-fluoroquinolone triple or quadruple therapy as a second-line treatment for Helicobacter pylori infection. An important caveat of amoxicillin-fluoroquinolone rescue therapy is poor eradication efficacy in the presence of fluoroquinolone resistance. The study aimed to investigate the efficacies of tetracycline-levofloxacin (TL) quadruple therapy and amoxicillin-levofloxacin (AL) quadruple therapy in the second-line treatment of H. pylori infection. Methods Consecutive H. pylori-infected subjects after the failure of first-line therapies were randomly allocated to receive either TL quadruple therapy (tetracycline 500 mg QID, levofloxacin 500 mg QD, esomeprazole 40 mg BID, and tripotassium dicitrato bismuthate 300 mg QID) or AL quadruple therapy (amoxicillin 500 mg QID, levofloxacin 500 mg QD, esomeprazole 40 mg BID, and tripotassium dicitrato bismuthate 300 mg QID) for 10 days. Post-treatment H. pylori status was assessed 6 weeks after the end of therapy. Results The study was early terminated after an interim analysis. In the TL quadruple group, 50 out of 56 patients (89.3%) had successful eradication of H. pylori infection. Cure of H. pylori infection was achieved only in 39 of 52 patients (69.6%) receiving AL quadruple therapy. Intention-to-treat analysis showed that TL quadruple therapy achieved a markedly higher eradication rate than AL quadruple therapy (95% confidence interval: 4.8% to 34.6%; p = 0.010). Further analysis revealed that TL quadruple therapy had a high eradication rate for both levofloxacin-susceptible and resistant strains (100% and 88.9%). In contrast, AL quadruple therapy yielded a high eradication for levofloxacin-susceptible strains (90.9%) but a poor eradication efficacy for levofloxacin-resistant strains (50.0%). The two therapies exhibited comparable frequencies of adverse events (37.5% vs 21.4%) and drug adherence (98.2% vs 94.6%). Conclusions Ten-day TL quadruple therapy is more effective than AL quadruple therapy in the second-line treatment of H. pylori infection in a population with high levofloxacin resistance.

A primordial gut-epithelial innate defense response is the release of hydrogen peroxide by dual NADPH oxidase (DUOX). In inflammatory bowel disease (IBD), a condition characterized by an imbalanced gut microbiota-immune homeostasis, DUOX2 isoenzyme is the highest induced gene. Performing multiomic analyses using 2872 human participants of a wellness program, we detected a substantial burden of rare protein-altering DUOX2 gene variants of unknown physiologic significance. We identified a significant association between these rare loss-of-function variants and increased plasma levels of interleukin-17C, which is induced also in mucosal biopsies of patients with IBD. DUOX2-deficient mice replicated increased IL-17C induction in the intestine, with outlier high Il17c expression linked to the mucosal expansion of specific Proteobacteria pathobionts. Integrated microbiota/host gene expression analyses in patients with IBD corroborated IL-17C as a marker for epithelial activation by gram-negative bacteria. Finally, the impact of DUOX2 variants on IL-17C induction provided a rationale for variant stratification in case control studies that substantiated DUOX2 as an IBD risk gene. Thus, our study identifies an association of deleterious DUOX2 variants with a preclinical hallmark of disturbed microbiota-immune homeostasis that appears to precede the manifestation of IBD.

The formation of Ca2+ microdomains during T cell activation is initiated by the production of nicotinic acid adenine dinucleotide phosphate (NAADP) from its reduced form NAADPH. The reverse reaction—NAADP to NAADPH—is catalyzed by glucose 6-phosphate dehydrogenase (G6PD). Here, we identified NADPH oxidases NOX and DUOX as NAADP-forming enzymes that convert NAADPH to NAADP under physiological conditions in vitro. T cells express NOX1, NOX2, and, to a minor extent, DUOX1 and DUOX2. Local and global Ca2+ signaling were decreased in mouse T cells with double knockout of Duoxa1 and Duoxa2 but not with knockout of Nox1 or Nox2. Ca2+ microdomains in the first 15 s upon T cell activation were significantly decreased in Duox2−/− but not in Duox1−/− T cells, whereas both DUOX1 and DUOX2 were required for global Ca2+ signaling between 4 and 12 min after stimulation. Our findings suggest that a DUOX2- and G6PD-catalyzed redox cycle rapidly produces and degrades NAADP through NAADPH as an inactive intermediate.

Inflammatory bowel disease is a chronic, relapsing-remitting gastrointestinal disorder which has become a serious global concern, and it imposes a great degree of health and economic burdens on communities worldwide. Although the presence of non-Helicobacter pylori Helicobacter (NHPH) microorganisms has been reported in various gastrointestinal disorders, their putative role in the pathogenesis of IBD has been a matter of controversy. The present study aimed to investigate the existence of gastric and enterohepatic NHPHs and their probable coinfection with H. pylori in IBD. Totally, 168 clinical specimens including 70 colonic biopsies and 98 fecal specimens were obtained from IBD patients. Genomic DNA was extracted from all samples, and its quality and concentration were assessed by β-globin PCR and spectrophotometry. The Helicobacter genus-specific PCR was performed using 16S rRNA gene. All samples were also tested for H. pylori infection by PCR of ureC gene fragment (glmM). The presence of NHPH was examined by using species-specific PCR assays. Based on PCR results, H. pylori was detected in 12.9% and 3.1% of colonic biopsies and fecal specimens, respectively. However, no statistically significant correlation was observed (P value > 0.05). We failed to find NHPH in both colonic biopsies and fecal specimens from IBD patients. Despite the fact that none of the IBD patients harbored the NHPH in the current work, further cohorts with larger sample size are required to determine the possible relationship between NHPH infection and IBD pathogenesis.

BACKGROUND: Helicobacter pylori infection leads to regulatory T-cell (Treg) induction in infected mice, which contributes to H. pylori immune escape. However, the mechanisms responsible for H. pylori induction of Treg and immune tolerance remain unclear. We hypothesized DC-produced TGF-β may be responsible for Treg induction and immune tolerance. MATERIALS AND METHODS: To test this hypothesis, we generated TGF-β(ΔDC) mice (CD11c(+) DC-specific TGF-β deletion) and assessed the impact of DC-specific TGF-β deletion on DC function during Helicobacter infection in vitro and in vivo. To examine the T-cell independent DC function, we crossed TGF-β(ΔDC) mice onto Rag1KO background to generate TGF-β(ΔDC)xRag1KO mice. RESULTS: When stimulated with H. pylori, TGF-β(ΔDC) BMDC/splenocyte cocultures showed increased levels of proinflammatory cytokines and decreased levels of anti-inflammatory cytokines compared to control, indicating a proinflammatory DC phenotype. Following 6 months of H. felis infection, TGF-β(ΔDC) mice developed more severe gastritis and a trend towards more metaplasia compared to TGF-β(fl/fl) with increased levels of inflammatory Th1 cytokine mRNA and lower gastric H. felis colonization compared to infected TGF-β(fl/fl) mice. In a T-cell deficient background using TGF-β(ΔDC)xRag1KO mice, H. felis colonization was significantly lower when DC-derived TGF-β was absent, revealing a direct, innate function of DC in controlling H. felis infection independent of Treg induction. CONCLUSIONS: Our findings indicate that DC-derived TGF-β mediates Helicobacter-induced Treg response and attenuates the inflammatory Th1 response. We also demonstrated a previously unrecognized innate role of DC controlling Helicobacter colonization via a Treg independent mechanism. DC TGF-β signaling may represent an important target in the management of H. pylori.

Accumulating evidence shows that agents targeting gut dysbiosis are effective for improving symptoms of irritable bowel syndrome (IBS). However, the potential mechanisms remain unclear. In this study we investigated the effects of berberine on the microbiota-gut-brain axis in two rat models of visceral hypersensitivity, i.e., specific pathogen-free SD rats subjected to chronic water avoidance stress (WAS) and treated with berberine (200 mg· kg−1 ·d−1, ig, for 10 days) as well as germ-free (GF) rats subjected to fecal microbiota transplantation (FMT) from a patient with IBS (designated IBS-FMT) and treated with berberine (200 mg· kg−1 ·d−1, ig, for 2 weeks). Before the rats were sacrificed, visceral sensation and depressive behaviors were evaluated. Then colonic tryptase was measured and microglial activation in the dorsal lumbar spinal cord was assessed. The fecal microbiota was profiled using 16S rRNA sequencing, and short chain fatty acids (SCFAs) were measured. We showed that berberine treatment significantly alleviated chronic WAS-induced visceral hypersensitivity and activation of colonic mast cells and microglia in the dorsal lumbar spinal cord. Transfer of fecal samples from berberine-treated stressed donors to GF rats protected against acute WAS. FMT from a patient with IBS induced visceral hypersensitivity and pro-inflammatory phenotype in microglia, while berberine treatment reversed the microglial activation and altered microbial composition and function and SCFA profiles in stools of IBS-FMT rats. We demonstrated that berberine did not directly influence LPS-induced microglial activation in vitro. In both models, several SCFA-producing genera were enriched by berberine treatment, and positively correlated to the morphological parameters of microglia. In conclusion, activation of microglia in the dorsal lumbar spinal cord was involved in the pathogenesis of IBS caused by dysregulation of the microbiota–gut–brain axis, and the berberine-altered gut microbiome mediated the modulatory effects of the agent on microglial activation and visceral hypersensitivity, providing a potential option for the treatment of IBS.

Development of gastric cancer is often preceded by chronic inflammation, but the immune cellular mechanisms underlying this process are unclear. Here we demonstrated that an inflammasome molecule, absent in melanoma 2 (Aim2), was upregulated in patients with gastric cancer and in spasmolytic polypeptide-expressing metaplasia of chronically Helicobacter felis–infected stomachs in mice. However, we found that Aim2 was not necessary for inflammasome function during gastritis. In contrast, Aim2 deficiency led to an increase in gastric CD8(+) T cell frequency, which exacerbated metaplasia. These gastric CD8(+) T cells from Aim2(–/–) mice were found to have lost their homing receptor expression (sphingosine-1-phosphate receptor 1 [S1PR1] and CD62L), a feature of tissue-resident memory T cells. The process was not mediated by Aim2-dependent regulation of IFN-β or by dendritic cell–intrinsic Aim2. Rather, Aim2 deficiency contributed to an increased production of CXCL16 by B cells, which could suppress S1PR1 and CD62L in CD8(+) T cells. This study describes a potentially novel function of Aim2 that regulates CD8(+) T cell infiltration and retention within chronically inflamed solid organ tissue. This function operates independent of the inflammasome, IFN-β, or dendritic cells. We provide evidence that B cells can contribute to this mechanism via CXCL16.

Background : The exact mechanism of how VSL#3 prevents ulcerative colitis (UC) carcinogenesis is still not clear. We aimed to explore the effect and mechanism of VSL#3 on UC carcinogenesis in mice and cell. Methods: In mice, C57BL/6 mice were given azoxymethane/dextran sulfate sodium to establish the UC carcinogenesis model. The treatment groups received 5-ASA, VSL#3, 5-ASA combined with VSL#3 by gavage. The tumor load was compared in each group. TNF-α, IL-6 levels in colon tissue, the transcription activity of NF-κB and TCF-4 as well as the β-catenin distribution in the nuclei were assessed. In cell, Caco-2 cells, CCC-HIE-2 cells was co-cultured with Bifidobacterium, and was stimulated by IL-6 and TNF-α respectively. The relative luciferase activity, mRNA and protein level of β-catenin, expression of β-catenin in nucleoprotein, level of inflammatory factors, and transcriptional activity of NF-κB and TCF-4 was measured. Results: In mice, compared with the model control group, in VSL#3 and 5-ASA+VSL#3 groups, the tumor loads significantly decreased, the TNF-α and IL-6 level, the transcription activity of NF-κB, β-catenin expression in the nuclei, and transcription activity of TCF-4 were significantly lower. In cell, the level of TNF-α and IL-6 was down-regulated, transcription activities of NF-κB and TCF-4 were decreased, and the expression level of β-catenin in nucleus was distinctly declined in the Bifidobacterium co-culture group compared with non-co-culture group. Conclusion: VSL#3 inhibit tumor formation in UC carcinogenesis mice model by regulating inflammatory and Wnt/β-catenin Pathway. Similarly, Bifidobacterium co-culture can inhibit the activity of Wnt/β-catenin pathway in cell. Key Words: VSL#3, Ulcerative colitis carcinogenesis, Wnt/β-catenin

Background: Accumulating evidence indicates that agents targeting gut dysbiosis are effective on improving symptoms in irritable bowel syndrome (IBS). However, the potential mechanisms remain unclear. Here, we investigated the roles of berberine in modulating the microbiota-gut-brain axis in models of IBS. Methods: Two models were used to mimic brain-gut axis dysfunction. Specific pathogen-free Sprague Dawley (SD) rats were subjected to water avoidance stress (WAS) and berberine treatment, and germ-free (GF) SD rats underwent fecal microbiota transplantation (FMT) from patient with IBS, followed by berberine or rifaximin gavage. Visceral sensation and depressive behaviors were assessed, colonic tryptase was measured, and microglial activation was evaluated. The fecal microbiota was profiled by 16S rRNA sequencing, and short chain fatty acids (SCFAs) were measured. Findings: Berberine alleviated stress-induced visceral hypersensitivity and activation of colonic mast cells and microglia. Transfer of fecal samples from berberine-treated stressed donors to GF rats showed protective effects against WAS. IBS-FMT induced visceral hypersensitivity and a pro-inflammatory phenotype of microglia. Berberine, not rifaximin, significantly reversed the activation of microglia, as well as altered microbial composition and function and SCFA profiles in stools of IBS-FMT rats. Pearson correlation analysis revealed positive correlations between SCFA-producing genera or probiotics and the morphological parameters of microglia. Interpretation: Berberine-altered gut microbiota mediated the modulating effects of the agent on microglial activation and visceral hypersensitivity, providing a potential option for the treatment of IBS. Funding Statement: National Natural Science Foundation of China (No.81670491) and Capital’s Funds for Health Improvement and Research (No.2016-2-4093). Declaration of Interests: The authors declare no conflicts of interest. Ethics Approval Statement: All protocols were approved by the Laboratory Animal Welfare Ethics branch of the Biomedical Ethics Committee of Peking University (approval no. LA2016230).

International audience; Metabolic reprogramming is associated with the adaptation of host cells to the disease environment, such as inflammation and cancer. However, little is known about microbial metabolic reprogramming or the role it plays in regulating the fitness of commensal and pathogenic bacteria in the gut. Here, we report that intestinal inflammation reprograms the metabolic pathways of Enterobacteriaceae, such as Escherichia coli LF82, in the gut to adapt to the inflammatory environment. We found that E. coli LF82 shifts its metabolism to catabolize L-serine in the inflamed gut in order to maximize its growth potential. However, L-serine catabolism has a minimal effect on its fitness in the healthy gut. In fact, the absence of genes involved in L-serine utilization reduces the competitive fitness of E. coli LF82 and Citrobacter rodentium only during inflammation. The concentration of luminal L-serine is largely dependent on dietary intake. Accordingly, withholding amino acids from the diet markedly reduces their availability in the gut lumen. Hence, inflammation-induced blooms of E. coli LF82 are significantly blunted when amino acids-particularly L-serine-are removed from the diet. Thus, the ability to catabolize L-serine increases bacterial fitness and provides Enterobacteriaceae with a growth advantage against competitors in the inflamed gut.

Outcomes of furazolidone- and amoxicillin-based quadruple therapy for Helicobacter pylori infection and predictors of failed eradication

A significant proportion of individuals develop recurrent Clostridium difficile infection (CDI) following initial disease. Fecal microbiota transplantation (FMT), a highly effective treatment method for recurrent CDI, has been demonstrated to induce microbiota recovery. One of the proposed functions associated with restoration of colonization resistance against C. difficile has been recovery of bile acid metabolism. In this study, we aimed to assess recovery of short chain fatty acids (SCFAs) in addition to bile acids alongside microbial community structure in six patients with recurrent CDI following treatment with FMT over time. Using 16S rRNA gene-based sequencing, we observed marked similarity of the microbiota between recipients following FMT (n = 6, sampling up to 6 months post-FMT) and their respective donors. Sustained increases in the levels of the SCFAs butyrate, acetate, and propionate were observed post-FMT, and variable recovery over time was observed in the secondary bile acids deoxycholate and lithocholate. To correlate these changes with specific microbial taxa at an individual level, we applied a generalized estimating equation approach to model metabolite concentrations with the presence of specific members of the microbiota. Metabolites that increased following FMT were associated with bacteria classified within the Lachnospiraceae, Ruminococcaceae, and unclassified Clostridiales families. In contrast, members of these taxa were inversely associated with primary bile acids. The longitudinal aspect of this study allowed us to characterize individualized patterns of recovery, revealing variability between and within patients following FMT.

The current practice guidelines recommend that Helicobacter pylori (H. pylori) culture and antimicrobial susceptibility testing (AST) be considered after patients failed the second course of H. pylori eradication therapy. Here we report the real life experience of following this recommendation in the USA. We established an in-house H. pylori culture protocol for AST and identified retrospectively patients who previously failed ≥ 2 courses of anti-H. pylori therapy and underwent esophagogastroduodenoscopy with AST at University of Michigan from 2010 to 2017. We determined the rate of H. pylori antibiotic resistance, the success rates of AST-guided tailored therapy, and the risk factors associated with treatment failure. Forty-seven patients were identified and 34 (72.3%) had successful cultures and AST. The most common antibiotic resistance was to metronidazole (79.4%), followed by clarithromycin (70.6%) and ciprofloxacin (42.9%). None of the patients were resistant to amoxicillin or tetracycline. The overall success rate of AST-guided tailored therapy was low (44.4%, 12/27). In patients infected with metronidazole-resistant H. pylori, bismuth quadruple therapy appears to be superior compared to non-bismuth quadruple therapy (6/8 or 75.0% vs. 3/14 or 21.4%, P = 0.03). High body mass index was significantly associated with tailored therapy failure (OR 1.24, 95% CI 1.00–1.54, P = 0.049). The success rate of AST-guided salvage therapy in the USA is low particularly in those with high BMI. Bismuth-based therapy appears to be better than non-bismuth-based regimens.

Introduction TGF-β is an important target for many cancer therapies under development. In addition to suppressing anti-tumor immunity, it has pleiotropic direct pro- and anti- tumor effects. The actions of increased endogenous TGF-β production remain unclear, and may affect the outcomes of anti-TGF-β cancer therapy. We hypothesize that tumor-derived TGF-β (td-TGF-β) plays an important role in maintaining tumor remission by controlling tumor proliferation in vivo, and that decreasing td-TGF-β in the tumor microenvironment will result in tumor progression. The aim of this study was to examine the effect of TGF-β in the tumor microenvironment on the balance between its anti-proliferative and immunosuppressive effects. Methods A murine BALB/c spontaneous colon adenocarcinoma cell line (CT26) was genetically engineered to produce increased active TGF-β (CT26-TGF-β), a dominant-negative soluble TGF-β receptor (CT26-TGF-β-R), or the empty neomycin cassette as control (CT26-neo). In vitro proliferation rates were measured. For in vivo studies, the three cell lines were injected into syngeneic BALB/c mice, and tumor growth was measured over time. Immunodeficient BALB/c nude mice were used to investigate the role of T and B cells. Results In vitro, CT26-TGF-β-R and CT26-TGF-β cells showed increased and suppressed proliferation, respectively, compared to control (CT26-neo), confirming TGF-β has direct anti-tumor effects. In vivo, we found that CT26-TGF-β-R cells displayed slower growth compared to control, likely secondary to reduced suppression of anti-tumor immunity, as this effect was ablated in immunodeficient BALB/c nude mice. However, CT26-TGF-β cells (excess TGF-β) exhibited rapid early growth compared to control, but later failed to progress. The same pattern was shown in immunodeficient BALB/c nude mice, suggesting the effect on tumor growth is direct, with minimal immune system involvement. There was minimal effect on systemic antitumor immunity as determined by peripheral antigen-specific splenocyte type 1 cytokine production and tumor growth rate of CT26-neo on the contralateral flank of the same mice. Conclusion Although TGF-β has opposing effects on tumor growth, this study showed that excessive td-TGF-β in the tumor microenvironment renders the tumor non-proliferative. Depleting excess td-TGF-β may release this endogenous tumor suppressive mechanism, thus triggering the progression of the tumor. Therefore, our findings support cautions against using anti-TGF-β strategies in treating cancer, as this may tip the balance of anti-immunity vs. anti-tumor effects of TGF-β, leading to tumor progression instead of remission.

Background & Aims Patients with isolated laryngopharyngeal reflux symptoms (LPRS) defined as those without concomitant typical reflux symptoms (CTRS) are clinically challenging to manage due to unclear pathophysiology. We investigated esophageal physiology in patients with isolated LPRS and their response to proton-pump inhibitors (PPI) therapy. Methods This is a multi-center observational study conducted in referral hospitals in Taiwan. Patients with predominant LPRS, but without common non-reflux causes, underwent esophageal manometry, 24-hr ambulatory esophagopharyngeal pH testing, and Bernstein test, followed by a 12-week esomeprazole 40 mg twice-daily treatment. Participants with pathological reflux were divided into the isolated LPRS group (ie, LPRS without CTRS, n = 40) and the CTRS group (ie, LPRS with CTRS, n = 66). Participants without pathological reflux or esophagitis (n = 132) served as the nonreflux controls. Results The PPI-responsiveness was similar between the isolated LPRS group and CTRS group (63% vs 57%, P = .8), but lower in the nonreflux controls (32%, P = .005). Despite similar distal esophageal acid exposure time (P = .7) when compared to those with CTRS, the isolated LPRS group had a lower prevalence of both positive Bernstein test (P = .001) and ineffective esophageal motility disorder (P = .03), and fewer pharyngeal acid reflux episodes (P Conclusions Our findings indicate similar distal esophageal acid exposure and PPI-responsiveness between LPRS patients with and without CTRS. The lack of CTRS in the isolated LPRS group is likely due to esophageal acid hyposensitivity and fewer pharyngeal acid reflux episodes, thus implicating distinct pathophysiology of isolated LPRS from those with CTRS.

Tissue resident memory (T RM ) T-cells are a novel population of tissue restricted antigen specific T-cells. T RM are induced by pathogens and promote host-defense to secondary infections. Although T RM cells cannot be detected in circulation, they are the major memory CD4 + and CD8 + T-cell population in tissues in mice and humans. Murine models of CD8 + T RM cells have shown that CD8 + T RM cells maintain tissue residency via CD69 and though tumor growth factor β dependent induction of CD103. In contrast to CD8 + T RM cells, there are few models of CD4 + T RM cells. Thus, much less is known about the factors regulating the induction, maintenance and host-defense functions of CD4 + T RM cells. Citrobacter rodentium is known to induce IL-17 + and IL-22 + CD4 + T-cells (‘T h 17′ and ‘T h 22′ cells, respectively). Moreover, data from IL-22 reporter mice shows that most IL-22 + cells in the colon 3 months post- C. rodentium are CD4 + T-cells. This, collectively suggests that C. rodentium may induce CD4 + T RM cells. Herein, we demonstrated that C. rodentium induces a population of IL-17A + CD4 + T cells that are tissue restricted and antigen specific thus meeting the criteria of CD4 + T RM cells. These cells expand and are a major source of IL-22 during secondary C. rodentium infection, even before the T-cell phase of the host response in primary infection. Finally, using FTY 720, which depletes circulating naive and effector T-cells but not tissue restricted T-cells, we show that these CD4 + T RM cells can promote host defense.

Background The empiric therapies for H. pylori infection in clinical guidelines have been widely used. However, the cure rate is decreasing due to the increase of antibiotic resistance. The importance of antimicrobial susceptibility test (AST) has been documented in many consensuses. However, the effect of tailored therapy remains controversial because the AST is rarely offered in most areas. We compared the evolution of treatment efficacy among tailored therapy and some recommended empiric therapies through a trend survey from 1999 to 2018. Methods This retrospective survey was performed at 2 medical centers and 3 community hospitals in Taiwan. A total of 16,370 treatment naive or failure patients were recruited. Successful H. pylori eradication was defined as a negative 13C-UBT. The empiric first-line regimens include tailored therapy, clarithromycin-containing triple therapy (CLA-TT), sequential therapy (ST), bismuth-containing quadruple therapy (BQT), and high-dose dual therapy (HDDT). The empiric rescue regimens include tailored therapy, levofloxacin-containing triple therapy (LEV-TT), BQT, and HDDT. We divided the 20 years of follow-up time into 4-year periods for evaluating the trend of treatment efficacies. The E-test was performed to evaluate H. pylori resistance. For the tailored therapy, CLA-TT, LEV-TT, BQT, or HDDT was chosen according to the resistance pattern of each patient. Results The efficacies of tailored therapy, BQT, and HDDT maintain a stable and high efficacy in both first-line and rescue treatment during the study period. However, the efficacies of CLA-TT, ST, and LEV-TT are decreasing year by year. The eradication rate of tailored therapy is significantly higher than that of CLA-TT, ST, LEV-TT, and BQT in recent 4-year period. However, there is no significant difference between the efficacy of tailored therapy and HDDT. The prevalence of H. pylori resistance to CLA and LEV increased gradually. In contrast, the resistance rate to amoxicillin and tetracycline remained low. Conclusions Over the past 20 years, we found that the efficacy of tailored therapy remains relatively stable. Of the recommended empiric therapies, HDDT and BQT have stable therapeutic efficacies and are a good choice of empiric treatment currently.

Background and Aims Tumour necrosis factor [TNF]α- and IL-17A-producing T cells are implicated in Crohn’s disease [CD]. Tissue-resident memory T [TRM] cells are tissue-restricted T cells that are regulated by PR zinc finger domain 1 [PRDM1], which has been implicated in pathogenic Th17 cell responses. TRM cells provide host defence but their role in CD is unknown. We thus examined CD4+ TRM cells in CD. Methods Colon samples were prospectively collected at endoscopy or surgery in CD and control subjects. Flow cytometry and ex vivo assays were performed to characterise CD4+ TRM cells. Results CD4+ TRM cells are the most abundant memory T cell population and are the major T cell source of mucosal TNFα in CD. CD4+ TRM cells are expanded in CD and more avidly produce IL-17A and TNFα relative to control cells. There was a unique population of TNFα+IL-17A+ CD4+ TRM cells in CD which are largely absent in controls. PRDM1 was highly expressed by CD4+ TRM cells but not by other effector T cells. Suppression of PRDM1 was associated with impaired induction of IL17A and TNFA by CD4+ TRM cells Conclusions CD4+ TRM cells are expanded in CD and are a major source of TNFα, suggesting that they are important in CD. PRDM1 is expressed by TRM cells and may regulate their function. Collectively, this argues for prospective studies tracking CD4+ TRM cells over the disease course.

Macrophages (Mϕs) are known to be major producers of the anti-inflammatory cytokine interleukin-10 (IL-10) in the intestine, thus playing an important role in maintaining gastrointestinal homeostasis. Mϕs that reside in the small intestine (SI) have been previously shown to be regulated by dietary antigens, while colonic Mϕs are regulated by the microbiota. However, the role which resident Mϕs play in SI homeostasis has not yet been fully elucidated. Here, we show that SI Mϕs regulate the integrity of the epithelial barrier via secretion of IL-10. We used an animal model of non-steroidal anti-inflammatory drug (NSAID)-induced SI epithelial injury to show that IL-10 is mainly produced by MHCII+ CD64+ Ly6Clow Mϕs early in injury and that it is involved in the restoration of the epithelial barrier. We found that a lack of IL-10, particularly its secretion by Mϕs, compromised the recovery of SI epithelial barrier. IL-10 production by MHCII+ CD64+ Ly6Clow Mϕs in the SI is not regulated by the gut microbiota, hence depletion of the microbiota did not influence epithelial regeneration in the SI. Collectively, these results highlight the critical role IL-10-producing Mϕs play in recovery from intestinal epithelial injury induced by NSAID.

BACKGROUND AND AIMS Anti-Helicobacter pylori therapy may lead to the growth of pathogenic or antibiotic-resistant bacteria in the gut. The study aimed to investigate the short-term and long-term impacts of H. pylori eradication with reverse hybrid therapy on the components and macrolide resistance of the gut microbiota. METHODS Helicobacter pylori-related gastritis patients were administered a 14-day reverse hybrid therapy. Fecal samples were collected before treatment and at the end of week 2, week 8, and week 48. The V3-V4 region of the bacterial 16S rRNA gene in fecal specimens was amplified by polymerase chain reaction and sequenced on Illumina MiSeq platform. Additionally, amplification of erm(B) gene (encoding erythromycin resistance methylase) was performed. RESULTS Reverse hybrid therapy resulted in decreased relative abundances of Firmicutes (from 62.0% to 30.7%; P

Background & Aims: Gut dysbiosis is closely involved in the pathogenesis of inflammatory bowel disease (IBD). However, it remains unclear whether IBD-associated gut dysbiosis contributes to disease pathogenesis or is merely secondary to intestinal inflammation. We established a humanized gnotobiotic (hGB) mouse system to assess the functional role of gut dysbiosis associated with 2 types of IBD: Crohn's disease (CD) and ulcerative colitis (UC). Methods: Germ-free mice were colonized by the gut microbiota isolated from patients with CD and UC, and healthy controls. Microbiome analysis, bacterial functional gene analysis, luminal metabolome analysis, and host gene expression analysis were performed in hGB mice. Moreover, the colitogenic capacity of IBD-associated microbiota was evaluated by colonizing germ-free colitis-prone interleukin 10âdeficient mice with dysbiotic patients' microbiota. Results: Although the microbial composition seen in donor patients' microbiota was not completely reproduced in hGB mice, some dysbiotic features of the CD and UC microbiota (eg, decreased diversity, alteration of bacterial metabolic functions) were recapitulated in hGB mice, suggesting that microbial community alterations, characteristic for IBD, can be reproduced in hGB mice. In addition, colonization by the IBD-associated microbiota induced a proinflammatory gene expression profile in the gut that resembles the immunologic signatures found in CD patients. Furthermore, CD microbiota triggered more severe colitis than healthy control microbiota when colonized in germ-free interleukin 10âdeficient mice. Conclusions: Dysbiosis potentially contributes to the pathogenesis of IBD by augmenting host proinflammatory immune responses. Transcript profiling: GSE73882. Keywords: Dysbiosis, Microbiota, Crohn's Disease, Ulcerative Colitis