Constitutive programmed death ligand 1 expression protects gastric G-cells from Helicobacter pylori–induced inflammation

INTRODUCTION: Gastric intestinal metaplasia (GIM) is a premalignant lesion, highly associated with Helicobacter pylori infection. Previous studies have shown that H. pylori is able to induce the expression of programmed death ligand 1 (PD‐L1), an inhibitory immune modulator, in gastric cells. Our aim was to investigate whether tissues from GIM patients may exploit PD‐L1 expression upon H. pylori infection to evade immunosurveillance. METHODS: Immunohistochemistry was performed for PD‐L1 and enteroendocrine markers somatostatin and gastrin on samples derived from a cohort of patients with known GIM, both before and after H. pylori eradication. To determine the identity of any observed PD‐L1‐positive cells, we performed multiplex immunofluorescent staining and analysis of single‐cell sequencing data. RESULTS: GIM tissue was rarely positive for PD‐L1. In normal glands from GIM patients, PD‐L1 was mainly expressed by gastrin‐positive G‐cells. While the D‐cell and G‐cell compartments were both diminished 2‐fold (p = .015 and p = .01, respectively) during H. pylori infection in the normal antral tissue of GIM patients, they were restored 1 year after eradication. The total number of PD‐L1‐positive cells was not affected by H. pylori, but the percentage of PD‐L1‐positive G‐cells was 30% higher in infected subjects (p = .011), suggesting that these cells are preferentially rescued from destruction. CONCLUSIONS: Antral G‐cells frequently express PD‐L1 during homeostasis. G‐cells seem to be protected from H. pylori‐induced immune destruction by PD‐L1 expression. GIM itself does not express PD‐L1 and is unlikely to escape immunosurveillance via expression of PD‐L1

The use of non-invasive stool tests for verification of Helicobacter pylori eradication and clarithromycin resistance

Background: Clarithromycin resistance of Helicobacter pylori (H. pylori) represents a major challenge in eradication therapy. In this study, we assessed if non-invasive stool tests can be used to verify successful H. pylori eradication and determine clarithromycin resistance. Materials and methods:In this prospective study, patients undergoing urea breath testing (UBT) for confirmation of H. pylori eradication were asked to collect the stool as both a dry fecal sample and fecal immunochemical test (FIT). Stool H. pylori antigen testing (SAT) was performed on these samples and assessed for its accuracy in eradication verification. Type and duration of antibiotic treatment were retrospectively collected from patient records and compared with clarithromycin resistance determined by PCR of stool samples. Results: H. pylori eradication information was available for a total of 145 patients (42.7% male, median age: 51.2). Successful eradication was achieved in 68.1% of patients. SAT on FIT samples had similar accuracy for eradication assessment compared to dry fecal samples, 72.1% [95% CI 61.4–81.2] versus 72.2% [95% CI 60.9–81.7]. Clarithromycin resistance rate was 13.4%. Conclusion: H. pylori antigen testing on FIT stool samples to verify H. pylori eradication is feasible and has similar accuracy as H. pylori antigen testing on dry stool samples. Dry stool, but not FIT, was suitable for non-invasive identification of H. pylori clarithromycin resistance by rt-PCR personalizing antibiotic treatment strategies without the need for invasive diagnostics is desirable, as the cure rate of first-line empirical H. pylori treatment remains low.</p

Increased Prevalence of Autoimmune Gastritis in Patients with a Gastric Precancerous Lesion

Background: Autoimmune gastritis (AIG), characterized with the presence of anti-parietal-cell antibodies (APCA), is a risk factor for gastric cancer. However, AIG may go underdiagnosed, especially in the case of H. pylori infection and the presence of gastric precancerous lesions (GPL), due to the ambiguous pathology and delayed symptom onset. Aim: Investigate the prevalence and characteristics of AIG in GPL patients. Methods:Prevalence of AIG was determined with the presence of APCA in patients with GPL (n = 256) and the control group (n = 70). Pathological characteristics and levels of gastrin 17 (G17), pepsinogen (PG) I and II and anti-Helicobacter pylori IgG were assessed in GPL cases, and the severity of intestinal metaplasia and gastric atrophy was scored by expert pathologists. Results: APCA positivity was observed in 18% of cases vs. 7% of controls (p = 0.033). Only 3/256 patients were previously diagnosed with AIG. The presence of APCA was associated with corpus-limited and extended GPL. A receiver operating curve analysis demonstrated that the G17 and PGI/II ratio could identify APCA-positive patients within GPL cases (AUC: 0.884). Conclusions: The prevalence of AIG is higher in patients with GPL but goes undiagnosed. Using G17 and PG I/II as diagnostic markers can help to identify patients with AIG and improve surveillance programs for patients with GPL.</p

Broadly neutralizing antibodies abrogate established hepatitis C virus infection

In most exposed individuals, hepatitis C virus (HCV) establishes a chronic infection; this long-term infection in turn contributes to the development of liver diseases such as cirrhosis and hepatocellular carcinoma. The role of antibodies directed against HCV in disease progression is poorly understood. Neutralizing antibodies (nAbs) can prevent HCV infection in vitro and in animal models. However, the effects of nAbs on an established HCV infection are unclear. We demonstrate that three broadly nAbs—AR3A, AR3B, and AR4A—delivered with adeno-associated viral vectors can confer protection against viral challenge in humanized mice. Furthermore, we provide evidence that nAbs can abrogate an ongoing HCV infection in primary hepatocyte cultures and in a human liver chimeric mouse model. These results showcase a therapeutic approach to interfere with HCV infection by exploiting a previously unappreciated need for HCV to continuously infect new hepatocytes to sustain a chronic infection

Toll-Like Receptor 1 Locus Re-examined in a Genome-Wide Association Study Update on Anti–Helicobacter pylori IgG Titers

Funding Information: Funding The Rotterdam Study I-II was supported by the Netherlands Organization of Scientific Research (NWO; 175.010.2005.011, 911-03-012), Research Institute for Diseases in the Elderly (RIDE; 014-93-015), Genomics Initiative/NWO (project no. 050-060-810), Erasmus Medical Center Rotterdam, Erasmus University Rotterdam, Netherlands Organization for the Health Research and Development (ZonMw), Ministry of Education, Culture, and Science and Ministry for Health, Welfare, and Sports, European Commission, and the Municipality of Rotterdam. GenerationR was supported by Erasmus Medical Center Rotterdam, Erasmus University Rotterdam, ZonMw (907.00303, 916.10159), NWO, and the Ministry for Health, Welfare and Sports. The Study of Health in Pomerania (SHIP) and SHIP-TREND were supported by Deutsche Krebshilfe/Dr Mildred-Scheel-Stiftung (109102), Deutsche Forschungsgemeinschaft (DFG GRK840-D2/E3/E4, MA 4115/1-2/3), Federal Ministry of Education and Research (BMBF GANI-MED 03IS2061A and BMBF 0314107, 01ZZ9603, 01ZZ0103, 01ZZ0403, 03ZIK012), the European Union (EU-FP-7-EPCTM and EU-FP7-REGPOT-2010-1), AstraZeneca (unrestricted grant), the Federal Ministry of Education and Research, Siemens Healthcare, the Federal State of Mecklenburg–West Pomerania, and the University of Greifswald. The Framingham Heart Study was supported by National Institutes of Health grants N01-HC-25195, HHSN268201500001I, and 75N92019D00031 (to Boston University) and the Division of Intramural Research, National Heart, Lung, and Blood Institute (NHLBI). The Multi-Ethnic Study of Atherosclerosis (MESA) and the MESA SHARe projects were supported by the NHLBI (75N92020D00001, HHSN268201500003I, N01-HC-95159, 75N92020D00005, N01-HC-95160, 75N92020D00002, N01-HC-95161, 75N92020D00003, N01-HC-95162, 75N92020D00006, N01-HC-95163, 75N92020D00004, N01-HC-95164, 75N92020D00007, N01-HC-95165, N01-HC-95166, N01-HC-95167, N01-HC-95168, N01-HC-95169, UL1-TR-000040, UL1-TR-001079, and UL1-TR-001420. Funding for SHARe genotyping was provided by NHLBI grant N02-HL-64278. Genotyping was performed at Affymetrix (Santa Clara, CA) and the Broad Institute of Harvard and MIT (Boston, MA) using the Affymetrix Genome-Wide Human SNP Array 6.0. The provision of genotyping data was supported in part by the National Center for Advancing Translational Sciences grant UL1TR001881, and the National Institute of Diabetes and Digestive and Kidney Disease Diabetes Research Center grant DK063491 to the Southern California Diabetes Endocrinology Research Center. The Epidemiological Investigations on Chances of Preventing Recognizing Early and Optimally Treating Chronic Diseases in an Elderly Population were supported by the State Ministry of Science, Research and Arts, Baden-Württemberg, Federal Ministry of Education and Research, and Federal Ministry of Family Affairs, Senior Citizens, Women and Youth. LATVIA was supported by the European Regional Development Fund (ERDF; 009/0220/1DP/1.1.1.2.0/09/APIA/VIAA/016), National Program for Research in Latvia, Ministry of Health (6-1396-2016), and Fundamental and Applied Research Projects Program in Latvia (project no. lzp-2018/1-0135). Funding Information: Conceptualization: Linda Broer, Manon C.W. Spaander, Fabian Frost, Stefan Weiss, Georg Homuth, Henry Völzke, Markus M. Lerch, Ben Schöttker, Hermann Brenner, Daniel Levy, Shih-Jen Hwang, Alexis C. Wood, Stephen S. Rich, Jerome I. Rotter, Kent D. Taylor, Russell P. Tracy, Edmond K. Kabagambe, Marcis Leja, Janis Klovins, Raitis Peculis, Dace Rudzite, Liene Nikitina-Zake, Girts Skenders, Vita Rovite, André Uitterlinden, Ernst J. Kuipers, Maikel P. Peppelenbosch, and additional members of Rotterdam Study I-II, GenerationR, Study of Health in Pomerania, Framingham Heart Study, Multi-Ethnic Study of Atherosclerosis, Epidemiological Investigations on Chances of Preventing Recognizing Early and Optimally Treating Chronic Diseases in an Elderly Population, and LATVIA cohorts not directly involved in this manuscript. Methodology: all authors. Investigation: all authors. Formal analysis of discovery: Linda Broer, Fabian Frost, Stefan Weiss, Georg Homuth, Henry Völzke, Markus M. Lerch, Daniel Levy, Shih-Jen Hwang, Alexis C. Wood, Stephen S. Rich, Jerome I. Rotter, Kent D. Taylor, Russell P. Tracy, and Edmond K. Kabagambe. Formal analysis of replication: Yan Zhang, Hannah Stocker, Hermann Brenner, Marcis Leja, Janis Klovins, and Raitis Peculis. Formal analysis of meta-analysis: Linda Broer. Project administration: Suk Yee Lam and Gwenny M. Fuhler. Resources: Fabian Frost, Stefan Weiss, Georg Homuth, Henry Völzke, Markus M. Lerch, Hermann Brenner, Daniel Levy, Shih-Jen Hwang, Alexis C. Wood, Stephen S. Rich, Jerome I. Rotter, Kent D. Taylor, Russell P. Tracy, Edmond K. Kabagambe, Marcis Leja, Janis Klovins, Dace Rudzite, Liene Nikitina-Zake, Girts Skenders, Vita Rovite, Ernst J. Kuipers, and Maikel P. Peppelenbosch. Supervision: Manon C.W. Spaander, Fabian Frost, Stefan Weiss, Georg Homuth, Henry Völzke, Markus M. Lerch, Hermann Brenner, Daniel Levy, Shih-Jen Hwang, Alexis C. Wood, Stephen S. Rich, Jerome I. Rotter, Kent D. Taylor, Russell P. Tracy, Edmond K. Kabagambe, Marcis Leja, Janis Klovins, Gwenny M. Fuhler, Maikel P. Peppelenbosch, and André Uitterlinden. Visualization: Suk Yee Lam, Michiel C. Mommersteeg, Bingting Yu, Linda Broer, and Gwenny M. Fuhler. Writing—original draft: Suk Yee Lam, Michiel C. Mommersteeg, and Gwenny M. Fuhler. Writing—reviewing and editing: all authors. Publisher Copyright: © 2022 The Author(s)Background & Aims: A genome-wide significant association between anti–Helicobacter pylori (H pylori) IgG titers and Toll-like receptor (TLR1/6/10) locus on 4p14 was demonstrated for individuals of European ancestry, but not uniformly replicated. We re-investigated this association in an updated genome-wide association study (GWAS) meta-analysis for populations with low gastric cancer incidence, address potential causes of cohort heterogeneity, and explore functional implications of genetic variation at the TLR1/6/10 locus. Methods: The dichotomous GWAS (25% individuals exhibiting highest anti–H pylori IgG titers vs remaining 75%) included discovery and replication sampls of, respectively, n = 15,685 and n = 9676, all of European ancestry. Longitudinal analysis of serologic data was performed on H pylori–eradicated subjects (n = 132) and patients under surveillance for premalignant gastric lesions (n = 107). TLR1/6/10 surface expression, TLR1 mRNA, and cytokine levels were measured in leukocyte subsets of healthy subjects (n = 26) genotyped for TLR1/6/10 variants. Results: The association of the TLR1/6/10 locus with anti–H pylori IgG titers (rs12233670; β = −0.267 ± SE 0.034; P = 4.42 × 10−15) presented with high heterogeneity and failed replication. Anti–H pylori IgG titers declined within 2–4 years after eradication treatment (P = 0.004), and decreased over time in patients with premalignant gastric lesions (P < 0.001). Variation at the TLR1/6/10 locus affected TLR1-mediated cytokine production and TLR1 surface expression on monocytes (P = 0.016) and neutrophils (P = 0.030), but not mRNA levels. Conclusions: The association between anti–H pylori IgG titers and TLR1/6/10 locus was not replicated across cohorts, possibly owing to dependency of anti–H pylori IgG titers on therapy, clearance, and antibody decay. H pylori–mediated immune cell activation is partly mediated via TLR1 signaling, which in turn is affected by genetic variation.publishersversionPeer reviewe

Accuracy of upper endoscopies with random biopsies to identify patients with gastric premalignant lesions who can safely be exempt from surveillance

Introduction: Guidelines recommend endoscopy with biopsies to stratify patients with gastric premalignant lesions (GPL) to high and low progression risk. High-risk patients are recommended to undergo surveillance. We aimed to assess the accuracy of guideline recommendations to identify low-risk patients, who can safely be discharged from surveillance. Methods: This study includes patients with GPL. Patients underwent at least two endoscopies with an interval of 1–6 years. Patients were defined ‘low risk’ if they fulfilled requirements for discharge, and ‘high risk’ if they fulfilled requirements for surveillance, according to European guidelines (MAPS-2012, updated MAPS-2019, BSG). Patients defined ‘low risk’ with progression of disease during follow-up (FU) were considered ‘misclassified’ as low risk. Results: 334 patients (median age 60 years IQR11; 48.7% ma

Analysis of Hepatitis C Virus Particle Heterogeneity in Immunodeficient Human Liver Chimeric fah-/- MiceSummary

Background & Aims: Hepatitis C virus (HCV) is a leading cause of chronic liver diseases and the most common indication for liver transplantation in the United States. HCV particles in the blood of infected patients are characterized by heterogeneous buoyant densities, likely owing to HCV association with lipoproteins. However, clinical isolates are not infectious in vitro and the relative infectivity of the particles with respect to their buoyant density therefore cannot be determined, pointing to the need for better in vivo model systems. Methods: To analyze the evolution of the buoyant density of in vivoâderived infectious HCV particles over time, we infected immunodeficient human liver chimeric fumaryl acetoacetate hydrolase-/- mice with J6/JFH1 and performed ultracentrifugation of infectious mouse sera on isopicnic iodixanol gradients. We also evaluated the impact of a high sucrose diet, which has been shown to increase very-low-density lipoprotein secretion by the liver in rodents, on lipoprotein and HCV particle characteristics. Results: Similar to the severe combined immunodeficiency disease/Albumin-urokinase plasminogen activator human liver chimeric mouse model, density fractionation of infectious mouse serum showed higher infectivity in the low-density fractions early after infection. However, over the course of the infection, viral particle heterogeneity increased and the overall in vitro infectivity diminished without loss of the human liver graft over time. In mice provided with a sucrose-rich diet we observed a minor shift in HCV infectivity toward lower density that correlated with a redistribution of triglycerides and cholesterol among lipoproteins. Conclusions: Our work indicates that the heterogeneity in buoyant density of infectious HCV particles evolves over the course of infection and can be influenced by diet. Keywords: HCV, Lipoprotein, Mouse Model, Human Liver Chimeric Mic

Platelet-dependent signaling and Low Molecular Weight Protein Tyrosine Phosphatase expression promote aggressive phenotypic changes in gastrointestinal cancer cells

Peer reviewe

Accuracy of upper endoscopies with random biopsies to identify patients with gastric premalignant lesions who can safely be exempt from surveillance

Introduction: Guidelines recommend endoscopy with biopsies to stratify patients with gastric premalignant lesions (GPL) to high and low progression risk. High-risk patients are recommended to undergo surveillance. We aimed to assess the accuracy of guideline recommendations to identify low-risk patients, who can safely be discharged from surveillance. Methods: This study includes patients with GPL. Patients underwent at least two endoscopies with an interval of 1–6 years. Patients were defined ‘low risk’ if they fulfilled requirements for discharge, and ‘high risk’ if they fulfilled requirements for surveillance, according to European guidelines (MAPS-2012, updated MAPS-2019, BSG). Patients defined ‘low risk’ with progression of disease during follow-up (FU) were considered ‘misclassified’ as low risk. Results: 334 patients (median age 60 years IQR11; 48.7% male) were included and followed for a median of 48 months. At baseline, 181/334 (54%) patients were defined low risk. Of these, 32.6% were ‘misclassified’, showing progression of disease during FU. If MAPS-2019 were followed, 169/334 (51%) patients were defined low risk, of which 32.5% were ‘misclassified’. If BSG were followed, 174/334 (51%) patients were defined low risk, of which 32.2% were ‘misclassified’. Seven patients developed gastric cancer (GC) or dysplasia, four patients were ‘misclassified’ based on MAPS-2012 and three on MAPS-2019 and BSG. By performing one additional endoscopy 72.9% (95% CI 62.4–83.3) of high-risk patients and all patients who developed GC or dysplasia were identified. Conclusion: One-third of patients that would have been discharged from GC surveillance, appeared to be ‘misclassified’ as low risk. One additional endoscopy will reduce this risk by 70%

Toll-Like Receptor 1 Locus Re-examined in a Genome-Wide Association Study Update on Anti–Helicobacter pylori IgG Titers

Background & Aims: A genome-wide significant association between anti–Helicobacter pylori (H pylori) IgG titers and Toll-like receptor (TLR1/6/10) locus on 4p14 was demonstrated for individuals of European ancestry, but not uniformly replicated. We re-investigated this association in an updated genome-wide association study (GWAS) meta-analysis for populations with low gastric cancer incidence, address potential causes of cohort heterogeneity, and explore functional implications of genetic variation at the TLR1/6/10 locus. Methods: The dichotomous GWAS (25% individuals exhibiting highest anti–H pylori IgG titers vs remaining 75%) included discovery and replication sampls of, respectively, n = 15,685 and n = 9676, all of European ancestry. Longitudinal analysis of serologic data was performed on H pylori–eradicated subjects (n = 132) and patients under surveillance for premalignant gastric lesions (n = 107). TLR1/6/10 surface expression, TLR1 mRNA, and cytokine levels were measured in leukocyte subsets of healthy subjects (n = 26) genotyped for TLR1/6/10 variants. Results: The association of the TLR1/6/10 locus with anti–H pylori IgG titers (rs12233670; β = −0.267 ± SE 0.034; P = 4.42 × 10−15) presented with high heterogeneity and failed replication. Anti–H pylori IgG titers declined within 2–4 years after eradication treatment (P = 0.004), and decreased over time in patients with premalignant gastric lesions (P < 0.001). Variation at the TLR1/6/10 locus affected TLR1-mediated cytokine production and TLR1 surface expression on monocytes (P = 0.016) and neutrophils (P = 0.030), but not mRNA levels. Conclusions: The association between anti–H pylori IgG titers and TLR1/6/10 locus was not replicated across cohorts, possibly owing to dependency of anti–H pylori IgG titers on therapy, clearance, and antibody decay. H pylori–mediated immune cell activation is partly mediated via TLR1 signaling, which in turn is affected by genetic variation