Evolution of the use, effectiveness and safety of bismuth-containing quadruple therapy for Helicobacter pylori infection between 2013 and 2021: results from the European registry on H. pylori management (Hp-EuReg).

BACKGROUND: Bismuth quadruple therapies (BQTs) including bismuth, a proton pump inhibitor (PPI) and two antibiotics have been shown to be highly effective for treating Helicobacter pylori infection even in areas of high bacterial antibiotic resistance. OBJECTIVE: To describe the time trends of use, effectiveness and safety of BQT in Europe using the European Registry on Helicobacter pylori Management (Hp-EuReg). DESIGN: Patients registered in the Hp-EuReg from 2013 to 2021 who had received BQT were included. The regimens prescribed, the number of eradication attempts, effectiveness, adherence and safety were analysed. The effectiveness was assessed by modified intention to treat (mITT). Time-trend and multivariate analyses were performed to determine variables that predicted treatment success. RESULTS: Of the 49 690 patients included in the Hp-EuReg, 15 582 (31%) had received BQT. BQT use increased from 8.6% of all treatments in 2013 to 39% in 2021. Single-capsule BQT-containing bismuth, metronidazole and tetracycline-plus a PPI (single-capsule BQT, ScBQT) was the most frequent treatment mode (43%). Schemes that obtained an effectiveness above 90% were the 10-day ScBQT and 14-day BQT using tetracycline plus metronidazole, or amoxicillin plus either clarithromycin or metronidazole. Only ScBQT achieved above 90% cure rates in all the geographical areas studied. Using the ScBQT scheme, adherence, the use of standard or high-dose PPIs, 14-day prescriptions and the use of BQT as first-line treatment were significantly associated with higher mITT effectiveness. CONCLUSION: The use of BQT increased notably in Europe over the study period. A 10-day ScBQT was the scheme that most consistently achieved optimal effectiveness. TRIAL REGISTRATION NUMBER: NCT02328131.

Risk Factors in Serrated Pathway Lesions: N-Glycosylation Profile as a Potential Biomarker of Progression to Malignancy.

Introduction: The serrated pathway contributes to interval colorectal cancers, highlighting the need for new biomarkers to assess lesion progression risk. The ß1,6-GlcNAc branched N-glycans expression in CRC cells was associated with an invasive phenotype and with immune evasion. Therefore, this study aims to identify potential risk factors for progression of serrated lesions (SLs) to malignancy, analyzing the N-glycosylation profile of epithelial/infiltrating immune cells. Methods: A retrospective cohort study was performed with data from 53 colonoscopies (48 patients). Sixty-three serrated pathway lesions (SPLs) were characterized based on N-glycosylation profile (lectin histochemistry/flow cytometry) and MGAT5 expression. Statistical analysis was performed to search for associations between the glycoprofile and clinical variables from each patient. Results: Increased ß1,6-GlcNAc branched N-glycans expression in epithelial cells is found associated with age (p = 0.007 in SPL), smoking (p = 0.038 in SL), increased BMI (p = 0.036 in sessile serrated lesions [SSL]), and polyp dimensions ≥10 mm (p = 0.001 in SL), while increased expression of these structures on immune cells is associated with synchronous CA number (CD4+T cells: p = 0.016; CD8+T cells: p = 0.044 in SL) and female gender (p = 0.026 in SL). Moreover, a lower high-mannose N-glycans expression in immune cells is associated with smoking (p = 0.010 in SPL) and synchronous CA presence (p = 0.010 in SPL). Higher expression of these glycans is associated with female (p = 0.016 in SL) and male (p = 0.044 in SL) gender, left colon location (p = 0.028), dysplasia (p = 0.028), and adenocarcinoma (p = 0.010). Conclusions: We identified an association between an abnormal glycoprofile and several clinical risk factors, proposing the N-glycosylation profile as a potential biomarker of tumor progression in the serrated pathway. The N-glycosylation anatomopathological profile analysis could be further used to decide shorter interval follow-up in patients with SPL.

Introdução: A via serreada contribui para os cancros colorretais de intervalo, destacando a necessidade de novos biomarcadores para determinar o risco de progressão destas lesões. A expressão de ß1,6-GlcNAc N-glicanos ramificados foi associada a um fenótipo invasivo e a evasão imune. Assim, este estudo tem como objetivo identificar potenciais fatores de risco de progressão das lesões serreadas para malignidade, analisando o perfil de N-glicosilação das células epiteliais/células imunitárias. Métodos: Foi realizado um estudo retrospetivo com dados de 53 colonoscopias (48 doentes). 63 lesões da via serreada foram caracterizadas segundo o perfil de N-glicosilação (histoquímica de lectinas/citometria de fluxo) e expressão de MGAT5. A análise estatística foi realizada para encontrar associações entre o perfil de N-glicosilação e as variáveis clínicas de cada doente. Resultados: O aumento da expressão de ß1,6-GlcNAc N-glicanos ramificados nas células epiteliais encontra-se associado com a idade (p = 0.007 nas SPL), tabagismo (p = 0.038 nas SL), aumento do BMI (p = 0.036 nas SSL), e pólipos com dimensões ≥10 mm (p = 0.001 nas SL), enquanto que o aumento destas estruturas nas células imunitárias está associado com o número de CA síncronos (células TCD4+: p = 0.016; células TCD8+: p = 0.044 nas SL) e o género feminino (p = 0.026 nas SL). Além disso, uma diminuição da expressão de N-glicanos ricos em manose está associada ao tabagismo (p = 0.010 para SPL) e a presença de adenomas síncronos (p = 0.010 nas SPL). A expressão aumentada destas estruturas está associado com o género feminino (p = 0.016 nas SSL), género masculino (p = 0.044 nas SSL), localização no cólon esquerdo (p = 0.028), displasia (p = 0­028) e adenocarcinoma (p = 0.010). Discussão/Conclusão: Identificámos uma associação entre um perfil de glicosilação anormal e vários fatores de risco clínicos, propondo o perfil de N-glicosilação como um potencial biomarcador de progressão tumoral na via serreada. A análise anatomopatológica do perfil de N-glicosilação pode vir a ser usada para decidir intervalos de follow-up mais curtos em doentes com SPL.

Role of compliance in Helicobacter pylori eradication treatment: Results of the European Registry on H. pylori management.

BACKGROUND: Adherence to Helicobacter pylori (H. pylori) eradication treatment is a cornerstone for achieving adequate treatment efficacy. OBJECTIVE: To determine which factors influence compliance with treatment. METHODS: A systematic prospective non-interventional registry (Hp-EuReg) of the clinical practice of European gastroenterologists. Compliance was considered adequate if ≥90% drug intake. Data were collected until September 2021 using the AEG-REDCap e-CRF and were subjected to quality control. Modified intention-to-treat analyses were performed. Multivariate analysis carried out the factors associated with the effectiveness of treatment and compliance. RESULTS: Compliance was inadequate in 646 (1.7%) of 38,698 patients. The non-compliance rate was higher in patients prescribed longer regimens (10-, 14-days) and rescue treatments, patients with uninvestigated dyspepsia/functional dyspepsia, and patients reporting adverse effects. Prevalence of non-adherence was lower for first-line treatment than for rescue treatment (1.5% vs. 2.2%; p < 0.001). Differences in non-adherence in the three most frequent first-line treatments were shown: 1.1% with proton pump inhibitor + clarithromycin + amoxicillin; 2.3% with proton pump inhibitor clarithromycin amoxicillin metronidazole; and 1.8% with bismuth quadruple therapy. These treatments were significantly more effective in compliant than in non-compliant patients: 86% versus 44%, 90% versus 71%, and 93% versus 64%, respectively (p < 0.001). In the multivariate analysis, the variable most significantly associated with higher effectiveness was adequate compliance (odds ratio, 6.3 [95%CI, 5.2-7.7]; p < 0.001). CONCLUSIONS: Compliance with Helicobacter pylori eradication treatment is very good. Factors associated with poor compliance include uninvestigated/functional dyspepsia, rescue-treatment, prolonged treatment regimens, the presence of adverse events, and the use of non-bismuth sequential and concomitant treatment. Adequate treatment compliance was the variable most closely associated with successful eradication.

Comparison of the management of Helicobacter pylori infection between the older and younger European populations.

The prevalence of Helicobacter pylori remains high in the older population. Specific age-related peculiarities may impact the outcomes of H. pylori treatment. The aim of the study was to evaluate the diagnostics and effectiveness of H. pylori eradication between the younger and older European populations. "European Registry on H. pylori Management (Hp-EuReg)" data from 2013 to 2022 were analyzed. Patients were divided into older (≥ 60 years) and younger (18-59 years) groups. Modified intention-to-treat (mITT) and per-protocol (PP) analysis was performed. 49,461 patients included of which 14,467 (29%) were older-aged. Concomitant medications and penicillin allergy were more frequent among the older patients. Differences between younger and older populations were observed in treatment duration in first-line treatment and in proton pump inhibitors (PPIs) doses in second-line treatment. The overall incidence of adverse events was lower in the older adults group. The overall first-line treatment mITT effectiveness was 88% in younger and 90% in the older patients (p < 0.05). The overall second-line mITT treatment effectiveness was 84% in both groups. The effectiveness of the most frequent first- and second-line triple therapies was suboptimal (< 90%) in both groups. Optimal efficacy (≥ 90%) was achieved by using bismuth and non-bismuth-based quadruple therapies. In conclusion, the approach to the diagnostics and treatment of H. pylori infection did not generally differ between younger and older patients. Main differences were reported in the concurrent medications, allergy to penicillin and adverse events both in first- and second-line treatment. Optimal effectiveness rates were mostly achieved by using bismuth and non-bismuth-based quadruple therapies. No clinically relevant differences in the effectiveness between the age groups were observed.

Analysis of Clinical Phenotypes through Machine Learning of First-Line H. pylori Treatment in Europe during the Period 2013-2022: Data from the European Registry on H. pylori Management (Hp-EuReg).

The segmentation of patients into homogeneous groups could help to improve eradication therapy effectiveness. Our aim was to determine the most important treatment strategies used in Europe, to evaluate first-line treatment effectiveness according to year and country. Data collection: All first-line empirical treatments registered at AEGREDCap in the European Registry on Helicobacter pylori management (Hp-EuReg) from June 2013 to November 2022. A Boruta method determined the "most important" variables related to treatment effectiveness. Data clustering was performed through multi-correspondence analysis of the resulting six most important variables for every year in the 2013-2022 period. Based on 35,852 patients, the average overall treatment effectiveness increased from 87% in 2013 to 93% in 2022. The lowest effectiveness (80%) was obtained in 2016 in cluster #3 encompassing Slovenia, Lithuania, Latvia, and Russia, treated with 7-day triple therapy with amoxicillin-clarithromycin (92% of cases). The highest effectiveness (95%) was achieved in 2022, mostly in Spain (81%), with the bismuth-quadruple therapy, including the single-capsule (64%) and the concomitant treatment with clarithromycin-amoxicillin-metronidazole/tinidazole (34%) with 10 (69%) and 14 (32%) days. Cluster analysis allowed for the identification of patients in homogeneous treatment groups assessing the effectiveness of different first-line treatments depending on therapy scheme, adherence, country, and prescription year.

Helicobacter pylori Diagnostic Tests Used in Europe: Results of over 34,000 Patients from the European Registry on Helicobacter pylori Management.

BACKGROUND AND AIMS: Several methods are available to diagnose Helicobacter pylori infection. Our objective was to evaluate the tests used for both the initial diagnosis and the confirmation of eradication after treatment in Europe. METHODS: The European Registry on the management of Helicobacter pylori infection is an international, multicentre, prospective, non-interventional registry aiming to evaluate the management of Helicobacter pylori-infected patients in Europe. Countries with at least 100 cases registered from June 2013 to April 2021, and with a validated diagnostic method were analysed. Data were quality reviewed. RESULTS: A total of 34,920 adult patients from 20 countries were included (mean age 51 years; 61% women). To establish the initial diagnosis, invasive tests were performed in 19,801 (71%) patients, non-invasive in 11,369 (41%), and both in 3437 (12%). The most frequent were histology (n = 11,885; 43%), a rapid urease test (n = 10,636; 38%) and an urea breath test (n = 7577; 27%). According to the age, invasive tests were indicated in 11,179 (77%) ≥50 years, and in 8603 (65%) <50 years. Depending on the country, the use of invasive tests ranged from 29-99% in <50 years to 60-99% in ≥50. Most of the tests used to confirm eradication were non-invasive (n = 32,540; 93%), with the urea breath test being the most frequent (n = 32,540; 78%). In 2983 (9%) post-treatment tests, histology (n = 1887; 5%) or a rapid urease test (n = 1223; 4%) were performed. CONCLUSION: A great heterogeneity was observed for the initial diagnosis and confirmation of the eradication. The reasons for the apparent lack of adherence to the clinical guidelines should be further explored.

Extracolonic tumours in a pedigree with EPCAM-related Lynch Syndrome.

Lynch Syndrome is characterized by phenotypic and genotypic heterogeneity. Despite scarce evidence, individuals with an EPCAM deletion appear to have a comparable risk of colorectal cancer (CRC) as MSH2 mutation carriers, but a lower risk of extracolonic cancer (such as endometrial cancer) unless the deletion extends close to the promoter of MSH2. A genotype-phenotype correlation is yet to be established for EPCAM alterations. In this report, we describe a family with EPCAM deletion characterized by a particularly aggressive phenotype and extracolonic cancer. We present a family with 5 members carrying an EPCAM deletion encompassing exons 8 and 9. Three female family members presented CRC at the ages of 32, 44 and 60 (mucinous moderately and well-differentiated adenocarcinoma); in two of them metachronous colon cancers and advanced adenomas were diagnosed in the intensive surveillance program. Two female patients (42 and 63 years-old) presented with gastric cancer (GC). Two patients presented with small bowel cancer at 51 and 60 years-old - the first one presented a metachronous jejunal cancer at 68 years. Only one family member was submitted to hemithyroidectomy due a right-lobe Hürthle cell carcinoma at 56 years-old. This report illustrates the existence of intrafamilial clinical heterogeneity among carriers of this EPCAM alteration, and hence the difficulty in predicting phenotype for EPCAM-associated Lynch syndrome.

Esophageal Bullous Pemphigoid.

Bullous pemphigoid is a rare autoimmune dermatologic disease that usually occurs in the elderly. Mucous membrane lesions occur in about 10-35% of patients and are almost always limited to the oral mucous membrane. Esophageal involvement is very rare (4% of cases) and usually presents with chest pain, dysphagia, and odynophagia, though patients are frequently asymptomatic. We report the case of newly diagnosed bullous pemphigoid in a 76-year-old man with a past medical history of dementia. He presented with cutaneous manifestations but also severe gastrointestinal bleeding due to extensive esophageal involvement. Although bullous pemphigoid is mainly a skin disease, mucous membrane lesions should not be overlooked as they are associated with an even poorer outcome. A high index of suspicion for esophageal involvement is needed as its presentation can be fatal, as with our patient. LEARNING POINTS: Bullous pemphigoid is a rare autoimmune disease that should be suspected in elderly patients with itchy cutaneous lesions.Mucous membrane lesions should always be evaluated, as they are associated with a poor prognosis, even if asymptomatic.Early diagnosis should be the main focus, as steroids, the mainstay of treatment, may not be effective in severe cases.

Bringing to Light the Risk of Colorectal Cancer in Inflammatory Bowel Disease: Mucosal Glycosylation as a Key Player.

Colitis-associated cancer is a major complication of inflammatory bowel disease remaining an important clinical challenge in terms of diagnosis, screening, and prognosis. Inflammation is a driving factor both in inflammatory bowel disease and cancer, but the mechanism underlying the transition from colon inflammation to cancer remains to be defined. Dysregulation of mucosal glycosylation has been described as a key regulatory mechanism associated both with colon inflammation and colorectal cancer development. In this review, we discuss the major molecular mechanisms of colitis-associated cancer pathogenesis, highlighting the role of glycans expressed at gut epithelial cells, at lamina propria T cells, and in serum proteins in the regulation of intestinal inflammation and its progression to colon cancer, further discussing its potential clinical and therapeutic applications.

Colitis-associated cancer (CAC) is a major complication of inflammatory bowel disease and the molecular mechanisms underlying CAC progression are still elusive. Protein glycosylation holds a great promise for improving the understanding of CAC immunopathogenesis, opening new avenues for clinical and therapeutic interventions.

Endoscopic Submucosal Dissection Skills Transfer to Clinical Practice after Hands-On Workshops: An International Survey.

BACKGROUND: Endoscopic submucosal dissection (ESD) is a complex procedure, requiring enhanced technical skills. Translation into clinical practice of ESD training programs has not been documented. Our aim was to assess ESD training pathways of endoscopists participating in dedicated workshops and its clinical impact on ESD outcomes. METHODS: Participants of live porcine models ESD workshops, from 2013 to 2019, were included. They were invited to complete a survey focusing on human ESD performance after training, prior skills/competencies, complete learning pathway, and clinical outcomes. RESULTS: From 118 invited participants, 40 (34%) completed the questionnaire. Nineteen (47%) endoscopists performed human ESD after the workshop, predominantly male (89%). At the beginning of human ESD, endoscopists had a mean of 7.7 (standard deviation (SD) 4.1) years of endoscopic experience and were all performing endoscopic mucosal resection (and emergency endoscopy. Before ESD practice, 100% of the participants were trained with live animal models and 68% with ex vivo models. The majority started clinical ESD in the lower third of the stomach or rectum (90%), with lesions ≤30 mm (89%). Each endoscopist performed a median of 19 (interquartile range 8-32) cumulative ESDs, over a mean of 3.9 (SD 2.0) years. Total en bloc resection rate was 92%, R0 resection rate 88%, and curative resection rate 86%, whereas adverse events remained <10%. Endoscopists with >10 human ESD procedures achieve clinical competence thresholds. CONCLUSIONS: Participants of ESD workshops are adequately skilled prior to clinical ESD, complying with recommendations for training and properly implementing the technique. Transfer to clinical practice, of prior ESD skills obtained in hands-on training courses, was documented. Structured training programs achieve clinical outcomes exceeding established standards, namely in the very initial clinical phase.

A Steep Early Learning Curve for Endoscopic Submucosal Dissection in the Live Porcine Model.

BACKGROUND: Endoscopic submucosal dissection (ESD) is a demanding procedure requiring high level of expertise. ESD training programs incorporate procedures with live animal models. This study aimed to assess the early learning curve for performing ESD on live porcine models by endoscopists without any or with limited previous ESD experience. METHODS: In a live porcine model ESD workshop, number of resections, completeness of the resections, en bloc resections, adverse events, tutor intervention, type of knife, ESD time and size of resected specimens were recorded. ESD speed was calculated. RESULTS: A total of 70 procedures were carried out by 17 trainees. The percentage of complete resections, en bloc resections and ESD speed increased from the first to the latest procedures (88.2%-100%, 76.5%-100%, 8.6-31.4 mm2/min, respectively). The number of procedures in which a trainee needed tutor intervention and the number of adverse events also decreased throughout the procedures (4 to 0 and 6 to 0, respectively). During the workshop, when participants changed to a different type of knife, ESD speed slightly decreased (18.5 mm2/min to 17.0 mm2/min) and adverse events increased again (0-2). CONCLUSIONS: Through successive procedures, complete resections, en bloc resections, and ESD speed improve whereas adverse events decrease, supporting the role of the live porcine model in the preclinical learning phase. Changing ESD knives has a momentarily negative impact on the learning curve.

Empirical Second-Line Therapy in 5000 Patients of the European Registry on Helicobacter pylori Management (Hp-EuReg).

BACKGROUND & AIMS: After a first Helicobacter pylori eradication attempt, approximately 20% of patients will remain infected. The aim of the current study was to assess the effectiveness and safety of second-line empiric treatment in Europe. METHODS: This international, multicenter, prospective, non-interventional registry aimed to evaluate the decisions and outcomes of H pylori management by European gastroenterologists. All infected adult cases with a previous eradication treatment attempt were registered with the Spanish Association of Gastroenterology-Research Electronic Data Capture until February 2021. Patients allergic to penicillin and those who received susceptibility-guided therapy were excluded. Data monitoring was performed to ensure data quality. RESULTS: Overall, 5055 patients received empiric second-line treatment. Triple therapy with amoxicillin and levofloxacin was prescribed most commonly (33%). The overall effectiveness was 82% by modified intention-to-treat analysis and 83% in the per-protocol population. After failure of first-line clarithromycin-containing treatment, optimal eradication (>90%) was obtained with moxifloxacin-containing triple therapy or levofloxacin-containing quadruple therapy (with bismuth). In patients receiving triple therapy containing levofloxacin or moxifloxacin, and levofloxacin-bismuth quadruple treatment, cure rates were optimized with 14-day regimens using high doses of proton pump inhibitors. However, 3-in-1 single capsule or levofloxacin-bismuth quadruple therapy produced reliable eradication rates regardless of proton pump inhibitor dose, duration of therapy, or previous first-line treatment. The overall incidence of adverse events was 28%, and most (85%) were mild. Three patients developed serious adverse events (0.3%) requiring hospitalization. CONCLUSIONS: Empiric second-line regimens including 14-day quinolone triple therapies, 14-day levofloxacin-bismuth quadruple therapy, 14-day tetracycline-bismuth classic quadruple therapy, and 10-day bismuth quadruple therapy (as a single capsule) provided optimal effectiveness. However, many other second-line treatments evaluated reported low eradication rates. ClincialTrials.gov number: NCT02328131.

Empirical rescue treatment of Helicobacter pylori infection in third and subsequent lines: 8-year experience in 2144 patients from the European Registry on H. pylori management (Hp-EuReg).

OBJECTIVE: To evaluate the use, effectiveness and safety of Helicobacter pylori empirical rescue therapy in third and subsequent treatment lines in Europe. DESIGN: International, prospective, non-interventional registry of the clinical practice of European gastroenterologists. Data were collected and quality reviewed until October 2021 at Asociación Española de Gastroenterología-Research Electronic Data Capture. All cases with three or more empirical eradication attempts were assessed for effectiveness by modified intention-to-treat and per-protocol analysis. RESULTS: Overall, 2144 treatments were included: 1519, 439, 145 and 41 cases from third, fourth, fifth and sixth treatment lines, respectively. Sixty different therapies were used; the 15 most frequently prescribed encompassed >90% of cases. Overall effectiveness remained <90% in all therapies. Optimised treatments achieved a higher eradication rate than non-optimised (78% vs 67%, p<0.0001). From 2017 to 2021, only 44% of treatments other than 10-day single-capsule therapy used high proton-pump inhibitor doses and lasted ≥14 days. Quadruple therapy containing metronidazole, tetracycline and bismuth achieved optimal eradication rates only when prescribed as third-line treatment, either as 10-day single-capsule therapy (87%) or as 14-day traditional therapy with tetracycline hydrochloride (95%). Triple amoxicillin-levofloxacin therapy achieved 90% effectiveness in Eastern Europe only or when optimised. The overall incidence of adverse events was 31%. CONCLUSION: Empirical rescue treatment in third and subsequent lines achieved suboptimal effectiveness in most European regions. Only quadruple bismuth-metronidazole-tetracycline (10-day single-capsule or 14-day traditional scheme) and triple amoxicillin-levofloxacin therapies reached acceptable outcomes in some settings. Compliance with empirical therapy optimisation principles is still poor 5 years after clinical practice guidelines update. TRIAL REGISTRATION NUMBER: NCT02328131.

Endoscopic submucosal dissection (ESD): how do Western endoscopists value animal models?

INTRODUCTION: Endoscopic Submucosal Dissection (ESD)was introduced in the West later than in the East. Our aim was to assess how Western endoscopists performing ESD have been trained and how they value animal models for training. MATERIAL AND METHODS: An online survey regarding training in ESD was sent to Western endoscopists who published articles on advanced resection techniques. RESULTS: From 279 endoscopists, 58 (21%) completed the questionnaire, of which 50 confirmed performance of clinical ESD. Endoscopists had a median of 15 years of endoscopic experience (IQR 9.75-20.25) and all of them were performing conventional EMR, before starting ESD. Prior to clinical ESD, 74% (n = 37) underwent training with ex vivo models, 84% (n = 42) with live animal models and 92% (n = 46) with at least, one of the two models. After starting clinical ESD, as trainers, 52% (n = 26) were involved with ex vivo and 60% (n = 30) with live animal models. Personal usefulness of ex vivo and live animal models was rated with a median of 9 (IQR 8-10) and 10 (IQR 8-10), out of 10, respectively. Courses with ex vivo and live animal models were considered a prerequisite before clinical practice by 84% (n = 42) and 78% (n = 39), respectively. CONCLUSIONS: Western endoscopists have extensive endoscopic experience before starting ESD. The majority had pre-clinical training with ex vivo and live animal models and more than half are acting as trainers of other endoscopists with these models. Animal models are considered very useful and deemed a prerequisite before clinical practice by the majority of the endoscopists.

Helicobacter pylori lipopolysaccharide structural domains and their recognition by immune proteins revealed with carbohydrate microarrays.

The structural diversity of the lipopolysaccharides (LPSs) from Helicobacter pylori poses a challenge to establish accurate and strain-specific structure-function relationships in interactions with the host. Here, LPS structural domains from five clinical isolates were obtained and compared with the reference strain 26695. This was achieved combining information from structural analysis (GC-MS and ESI-MSn) with binding data after interrogation of a LPS-derived carbohydrate microarray with sequence-specific proteins. All LPSs expressed Lewisx/y and N-acetyllactosamine determinants. Ribans were also detected in LPSs from all clinical isolates, allowing their distinction from the 26695 LPS. There was evidence for 1,3-d-galactans and blood group H-type 2 sequences in two of the clinical isolates, the latter not yet described for H. pylori LPS. Furthermore, carbohydrate microarray analyses showed a strain-associated LPS recognition by the immune lectins DC-SIGN and galectin-3 and revealed distinctive LPS binding patterns by IgG antibodies in the serum from H. pylori-infected patients.

Glycans as Immune Checkpoints: Removal of Branched N-glycans Enhances Immune Recognition Preventing Cancer Progression.

Tumor growth is accompanied with dramatic changes in the cellular glycome, such as the aberrant expression of complex branched N-glycans. However, the role of this protumoral N-glycan in immune evasion and whether its removal contributes to enhancement of immune recognition and to unleashing an antitumor immune response remain elusive. We demonstrated that branched N-glycans are used by colorectal cancer cells to escape immune recognition, instructing the creation of immunosuppressive networks through inhibition of IFNγ. The removal of this "glycan-mask" exposed immunogenic mannose glycans that potentiated immune recognition by DC-SIGN-expressing immune cells, resulting in an effective antitumor immune response. We revealed a glycoimmune checkpoint in colorectal cancer, highlighting the therapeutic efficacy of its deglycosylation to potentiate immune recognition and, thus, improving cancer immunotherapy.

Genetic Variants of the MGAT5 Gene Are Functionally Implicated in the Modulation of T Cells Glycosylation and Plasma IgG Glycome Composition in Ulcerative Colitis.

OBJECTIVES: The impact of genetic variants (single nucleotide polymorphisms [SNPs]) in the clinical heterogeneity of ulcerative colitis (UC) remains unclear. We showed that patients with UC exhibit a deficiency in MGAT5 glycogene transcription in intestinal T cells associated with a hyperimmune response. Herein, we evaluated whether MGAT5 SNPs might functionally impact on T cells glycosylation and plasma IgG glycome in patients with UC, as well as in UC clinical outcomes. METHODS: Three selected MGAT5 SNPs (rs3814022, rs4953911, and rs1257220), previously associated with severity of autoimmune disease or with plasma glycome composition in healthy individuals, were functionally evaluated in patients with UC through analysis of MGAT5 mRNA levels in colonic (n = 14) and circulating (n = 24) T cells and through profiling the plasma IgG Fc glycosylation (n = 152). MGAT5 SNPs were genotyped in 931 patients with UC from 2 European cohorts and further associated with patients' prognosis. Targeted next-generation sequencing for MGAT5 coding and regulatory regions was also performed. RESULTS: MGAT5 SNPs were shown to be functionally associated with low transcription levels of MGAT5 in colonic and circulating T cells from patients with UC and with agalactosylation of IgGs, often associated with a proinflammatory phenotype. The SNPs rs3814022 and rs4953911 were further associated with the need of biologics. Next-generation sequencing data further revealed a combination of MGAT5 SNPs that stratify patients with UC according to their severity. DISCUSSION: Our results revealed that MGAT5 SNPs have a phenotypic impact on T cells glycosylation and in plasma IgG glycome composition associated with UC pathogenesis. MGAT5 SNPs display a tendency in the association with a worse disease course in patients with UC.