Development of non-alcoholic steatohepatitis is associated with gut microbiota but not with oxysterol enzymes CH25H, EBI2, or CYP7B1 in mice.

Liver steatosis is the most frequent liver disorder and its advanced stage, non-alcoholic steatohepatitis (NASH), will soon become the main reason for liver fibrosis and cirrhosis. The "multiple hits hypothesis" suggests that progression from simple steatosis to NASH is triggered by multiple factors including the gut microbiota composition. The Epstein Barr virus induced gene 2 (EBI2) is a receptor for the oxysterol 7a, 25-dihydroxycholesterol synthesized by the enzymes CH25H and CYP7B1. EBI2 and its ligand control activation of immune cells in secondary lymphoid organs and the gut. Here we show a concurrent study of the microbial dysregulation and perturbation of the EBI2 axis in a mice model of NASH.We used mice with wildtype, or littermates with CH25H-/-, EBI2-/-, or CYP7B1-/- genotypes fed with a high-fat diet (HFD) containing high amounts of fat, cholesterol, and fructose for 20 weeks to induce liver steatosis and NASH. Fecal and small intestinal microbiota samples were collected, and microbiota signatures were compared according to genotype and NASH disease state.We found pronounced differences in microbiota composition of mice with HFD developing NASH compared to mice did not developing NASH. In mice with NASH, we identified significantly increased 33 taxa mainly belonging to the Clostridiales order and/ or the family, and significantly decreased 17 taxa. Using an Elastic Net algorithm, we suggest a microbiota signature that predicts NASH in animals with a HFD from the microbiota composition with moderate accuracy (area under the receiver operator characteristics curve = 0.64). In contrast, no microbiota differences regarding the studied genotypes (wildtype vs knock-out CH25H-/-, EBI2-/-, or CYP7B1-/-) were observed.In conclusion, our data confirm previous studies identifying the intestinal microbiota composition as a relevant marker for NASH pathogenesis. Further, no link of the EBI2 - oxysterol axis to the intestinal microbiota was detectable in the current study.

Antenatal gut microbiome profiles and effect on pregnancy outcome in HIV infected and HIV uninfected women in a resource limited setting.

BACKGROUND: Human immunodeficiency virus (HIV) severely damages the epithelial cells of the gut lining leading to an inflamed leaky gut, translocation of microbial products, and dysbiosis resulting in systemic immune activation. Also, microbiota composition and maternal gut function can be altered in pregnancy through changes in the immune system and intestinal physiology. The aim of this study was to investigate the gut microbiota in HIV-infected and HIV-uninfected pregnant women and to compare and identify the association between gut microbial composition and adverse birth outcomes. RESULTS: A total of 94 pregnant women (35 HIV-infected and 59 HIV-uninfected controls) were recruited in Harare from 4 polyclinics serving populations with relatively poor socioeconomic status. Women were of a median age of 28 years (interquartile range, IQR: 22.3-32.0) and 55% of women were 35 weeks gestational age at enrolment (median 35.0 weeks, IQR: 32.5-37.2). Microbiota profiling in these participants showed that species richness was significantly lower in the HIV-infected pregnant women compared to their HIV-uninfected peers and significant differences in ß-diversity using Bray-Curtis dissimilarity were observed. In contrast, there was no significant difference in α-diversity between immune-compromised (CD4+ < 350 cells/µL) and immune-competent HIV-infected women (CD4+ ≥ 350 cells/µL) even after stratification by viral load suppression. HIV infection was significantly associated with a reduced abundance of Clostridium, Turicibacter, Ruminococcus, Parabacteroides, Bacteroides, Bifidobacterium, Treponema, Oscillospira, and Faecalibacterium and a higher abundance of Actinomyces, and Succinivibrio. Low infant birth weight (< 2500 g) was significantly associated with high abundances of the phylum Spirochaetes, the families Spirochaeteceae, Veillonellaceae, and the genus Treponema. CONCLUSION: The results reported here show that the species richness and taxonomy composition of the gut microbiota is altered in HIV-infected pregnant women, possibly reflecting intestinal dysbiosis. Some of these taxa were also associated with low infant birth weight.

The Bern Birth Cohort (BeBiCo) to study the development of the infant intestinal microbiota in a high-resource setting in Switzerland: rationale, design, and methods.

BACKGROUND: Microbiota composition is fundamental to human health with the intestinal microbiota undergoing critical changes within the first two years of life. The developing intestinal microbiota is shaped by maternal seeding, breast milk and its complex constituents, other nutrients, and the environment. Understanding microbiota-dependent pathologies requires a profound understanding of the early development of the healthy infant microbiota. METHODS: Two hundred and fifty healthy pregnant women (≥20 weeks of gestation) from the greater Bern area will be enrolled at Bern University hospital's maternity department. Participants will be followed as mother-baby pairs at delivery, week(s) 1, 2, 6, 10, 14, 24, 36, 48, 96, and at years 5 and 10 after birth. Clinical parameters describing infant growth and development, morbidity, and allergic conditions as well as socio-economic, nutritional, and epidemiological data will be documented. Neuro-developmental outcomes and behavior will be assessed by child behavior checklists at and beyond 2 years of age. Maternal stool, milk, skin and vaginal swabs, infant stool, and skin swabs will be collected at enrolment and at follow-up visits. For the primary outcome, the trajectory of the infant intestinal microbiota will be characterized by 16S and metagenomic sequencing regarding composition, metabolic potential, and stability during the first 2 years of life. Secondary outcomes will assess the cellular and chemical composition of maternal milk, the impact of nutrition and environment on microbiota development, the maternal microbiome transfer at vaginal or caesarean birth and thereafter on the infant, and correlate parameters of microbiota and maternal milk on infant growth, development, health, and mental well-being. DISCUSSION: The Bern birth cohort study will provide a detailed description and normal ranges of the trajectory of microbiota maturation in a high-resource setting. These data will be compared to data from low-resource settings such as from the Zimbabwe-College of Health-Sciences-Birth-Cohort study. Prospective bio-sampling and data collection will allow studying the association of the microbiota with common childhood conditions concerning allergies, obesity, neuro-developmental outcomes , and behaviour. Trial registration The trial has been registered at www. CLINICALTRIALS: gov , Identifier: NCT04447742.

Immune activation and inflammation in lactating women on combination antiretroviral therapy: role of gut dysfunction and gut microbiota imbalance.

Introduction: Combination antiretroviral therapy (cART) effectively controls HIV; however, chronic low-level viremia and gut microbiota dysbiosis remain significant drivers of gut and systemic inflammation. In this study, we explored the relationship between gut microbiota composition, intestinal inflammation, microbial translocation, and systemic inflammation in women on cART in Sub-Saharan Africa. Methods: We conducted a study in HIV-infected and HIV-uninfected lactating women followed up at 6 weeks and 6 months postpartum in Harare, Zimbabwe. We used 16S ribosomal Ribonucleic Acid (rRNA) sequencing and MesoScale Discovery V-Plex assays to examine the gut microbiome and to quantify plasma inflammatory biomarkers, respectively. In addition, we measured fecal calprotectin, plasma lipopolysaccharide-binding protein (LBP), and soluble cluster of differentiation 14 (sCD14) by enzyme-linked immunosorbent assay to assess gut inflammation, microbial translocation, and monocyte/macrophage activation. Results: A group of 77 lactating women were studied, of which 35% were HIV-infected. Fecal calprotectin levels were similar by HIV status at both follow-up time points. In the HIV-infected group at 6 weeks postpartum, fecal calprotectin was elevated: median (interquartile range) [158.1 µg/g (75.3-230.2)] in women who had CD4+ T-lymphocyte counts <350 cells/µL compared with those with ≥350 cells/µL [21.1 µg/g (0-58.4)], p = 0.032. Plasma sCD14 levels were significantly higher in the HIV-infected group at both 6 weeks and 6 months postpartum, p < 0.001. Plasma LBP levels were similar, but higher levels were observed in HIV-infected women with elevated fecal calprotectin. We found significant correlations between fecal calprotectin, LBP, and sCD14 with proinflammatory cytokines. Gut microbial alpha diversity was not affected by HIV status and was not affected by use of antibiotic prophylaxis. HIV significantly affected microbial beta diversity, and significant differences in microbial composition were noted. The genera Slackia and Collinsella were relatively more abundant in the HIV-infected group, whereas a lower relative abundance of Clostriduim sensu_stricto_1 was observed. Our study also found correlations between gut microbial taxa abundance and systemic inflammatory biomarkers. Discussion and conclusion: HIV-infected lactating women had increased immune activation and increased microbial translocation associated with increased gut inflammation. We identified correlations between the gut inflammation and microbial composition, microbial translocation, and systemic inflammation. The interplay of these parameters might affect the health of this vulnerable population.

Because I'm happy - positive affect and its predictive value for future disease activity in patients with inflammatory bowel diseases: a retrospective cohort study.

Background: While the detrimental impact of negative emotions on the clinical course of inflammatory bowel disease (IBD) and quality of life has been extensively investigated, evidence for a potential impact of positive emotions is scarce. Objectives: We aim to analyse contributing factors of positive affect and their predictive value for disease course in IBD patients. Design: In this retrospective cohort study, epidemiological, psychosocial and IBD disease characteristics of Swiss IBD cohort study patients were analysed longitudinally. Methods: Epidemiological, psychosocial and disease characteristics were extracted from the database of the Swiss IBD cohort study. Participants' positive emotions were assessed cross-sectionally with the seven-item Marburg questionnaire (range 1-6) addressing positive affect in different aspects of daily life. Predictors of positive emotions were identified by linear regression. The quantitative longitudinal impact of positive emotions on the further disease course was analysed using a multivariable Cox proportional hazards model. Results: Among 702 IBD patients, those reporting more positive emotions were found to have significantly less intense medical treatment, less pain and fewer depressive symptoms (p < 0.05). A higher percentage of variability in positive emotions was explained by pain (36%) and depressive symptoms (13%) than by epidemiological characteristics (0.3%), or characteristics of IBD and its treatment (2.4%). Patients with higher levels of positive emotions (score > 3.5) experienced longer flare-free survival, also after adjusting for confounders (adjusted hazard ratio: 0.39, p < 0.05). Conclusions: The absence of pain and depressive symptoms were the strongest drivers for high positive affect. Higher scores of positive affect were associated with longer disease-free survival in IBD patients.

Systemic and T cell-associated responses to SARS-CoV-2 immunisation in gut inflammation (STAR SIGN study): effects of biologics on vaccination efficacy of the third dose of mRNA vaccines against SARS-CoV-2.

BACKGROUND: Immunosuppressed patients with inflammatory bowel disease (IBD) experience increased risk of vaccine-preventable diseases such as COVID-19. AIMS: To assess humoral and cellular immune responses following SARS-CoV-2 booster vaccination in immunosuppressed IBD patients and healthy controls. METHODS: In this prospective, multicentre, case-control study, 139 IBD patients treated with biologics and 110 healthy controls were recruited. Serum anti-SARS-CoV-2 spike IgG concentrations were measured 2-16 weeks after receiving a third mRNA vaccine dose. The primary outcome was to determine if humoral immune responses towards booster vaccines differ in IBD patients under anti-TNF versus non-anti-TNF therapy and healthy controls. Secondary outcomes were antibody decline, impact of previous infection and SARS-CoV-2-targeted T cell responses. RESULTS: Anti-TNF-treated IBD patients showed reduced anti-spike IgG concentrations (geometric mean 2357.4 BAU/ml [geometric SD 3.3]) when compared to non-anti-TNF-treated patients (5935.7 BAU/ml [3.9]; p < 0.0001) and healthy controls (5481.7 BAU/ml [2.4]; p < 0.0001), respectively. In multivariable modelling, prior infection (geometric mean ratio 2.00 [95% CI 1.34-2.90]) and vaccination with mRNA-1273 (1.53 [1.01-2.27]) increased antibody concentrations, while anti-TNF treatment (0.39 [0.28-0.54]) and prolonged time between vaccination and antibody measurement (0.72 [0.58-0.90]) decreased anti-SARS-CoV-2 spike antibodies. Antibody decline was comparable in IBD patients independent of anti-TNF treatment and antibody concentrations could not predict breakthrough infections. Cellular and humoral immune responses were uncoupled, and more anti-TNF-treated patients than healthy controls developed inadequate T cell responses (15/73 [20.5%] vs 2/100 [2.0%]; p = 0.00031). CONCLUSIONS: Anti-TNF-treated IBD patients have impaired humoral and cellular immunogenicity following SARS-CoV-2 booster vaccination. Fourth dose administration may be beneficial for these patients.

STAR SIGN study: Evaluation of COVID-19 vaccine efficacy against the SARS-CoV-2 variants BQ.1.1 and XBB.1.5 in patients with inflammatory bowel disease.

BACKGROUND: Vaccine-elicited immune responses are impaired in patients with inflammatory bowel disease (IBD) treated with anti-TNF biologics. AIMS: To assess vaccination efficacy against the novel omicron sublineages BQ.1.1 and XBB.1.5 in immunosuppressed patients with IBD. METHODS: This prospective multicentre case-control study included 98 biologic-treated patients with IBD and 48 healthy controls. Anti-spike IgG concentrations and surrogate neutralisation against SARS-CoV-2 wild-type, BA.1, BA.5, BQ.1.1, and XBB.1.5 were measured at two different time points (2-16 weeks and 22-40 weeks) following third dose vaccination. Surrogate neutralisation was based on antibody-mediated blockage of ACE2-spike protein-protein interaction. Primary outcome was surrogate neutralisation against tested SARS-CoV-2 sublineages. Secondary outcomes were proportions of participants with insufficient surrogate neutralisation, impact of breakthrough infection, and correlation of surrogate neutralisation with anti-spike IgG concentration. RESULTS: Surrogate neutralisation against all tested sublineages was reduced in patients with IBD who were treated with anti-TNF biologics compared to patients treated with non-anti-TNF biologics and healthy controls (each p ≤ 0.001) at visit 1. Anti-TNF therapy (odds ratio 0.29 [95% CI 0.19-0.46]) and time since vaccination (0.85 [0.72-1.00]) were associated with low, and mRNA-1273 vaccination (1.86 [1.12-3.08]) with high wild-type surrogate neutralisation in a ß-regression model. Accordingly, higher proportions of patients treated with anti-TNF biologics had insufficient surrogate neutralisation against omicron sublineages at visit 1 compared to patients treated with non-anti-TNF biologics and healthy controls (each p ≤ 0.015). Surrogate neutralisation against all tested sublineages decreased over time but was increased by breakthrough infection. Anti-spike IgG concentrations correlated with surrogate neutralisation. CONCLUSIONS: Patients with IBD who are treated with anti-TNF biologics show impaired neutralisation against novel omicron sublineages BQ.1.1 and XBB.1.5 and may benefit from prioritisation for future variant-adapted vaccines.

The personality traits activity, self-reproach, and negative affect jointly predict clinical recurrence, depressive symptoms, and low quality of life in inflammatory bowel disease patients.

BACKGROUND: The bidirectional "gut-brain axis" has been implicated in the pathogenesis of inflammatory bowel diseases (IBD). While the influence of stress and depressive symptoms on IBD is well-characterized, the role of personality remains insufficiently investigated. METHODS: Personality was assessed in 1154 Swiss IBD cohort study (SIBDCS) patients via the NEO-Five-Factor Inventory (NEO-FFI) as well as in 2600 participants of the population-based CoLaus¦PsyCoLaus cohort study (NEO-FFI-revised). The NEO-FFI subcomponents activity, self-reproach and negative affect were associated with higher IBD disease activity and were combined to a NEO-FFI risk score. This risk score was validated and its effect on clinical IBD course and psychological endpoints was analysed in time-to-event and cumulative incidence analyses. RESULTS: In time-to-event analyses, a high NEO-FFI risk score was predictive for the clinical endpoints of new extraintestinal manifestation [EIM, adjusted hazard ratio (aHR) = 1.64, corrected p value (q) = 0.036] and two established composite flare endpoints (aHR = 1.53-1.63, q = 0.003-0.006) as well as for the psychological endpoints depressive symptoms (aHR = 7.06, q < 0.001) and low quality of life (aHR = 3.06, q < 0.001). Furthermore, cumulative incidence analyses showed that patients at high NEO-FFI risk experienced significantly more episodes of active disease, new EIMs, one of the flare endpoints, depressive episodes and low disease-related quality of life. Personalities of IBD patients showed only minor differences from the general population sample (Pearson's r = 0.03-0.14). CONCLUSIONS: Personality assessed by the NEO-FFI contained considerable predictive power for disease recurrence, depressive symptoms and low quality of life in IBD patients. Nevertheless, the personalities of IBD patients did not substantially differ from the general population.

Stromal PD-1/PD-L1 Expression Predicts Outcome in Colon Cancer Patients.

INTRODUCTION: The programmed cell death 1 (PD-1)/programmed cell death ligand 1 (PD-L1) axis plays an important role in controlling immune suppression by down-regulating T effector cell activities, enabling tumor cells to escape from the host's antitumor immunsurveillance. While only a small part of colon cancer cells express PD-L1, we sought to evaluate the differential impact of stromal and epithelial PD-L1 expression of primary tumors and liver metastasis on overall survival (OS) in colon cancer patients. PATIENTS AND METHODS: Using a next-generation tissue microarray approach, we assessed both epithelial and stromal PD-L1 expression levels in primary tumors (n = 279) and corresponding liver metastases (n = 14) of colon cancer patients. PD-L1 positivity was graded according to the percentage (0.1%-1%, > 1%, > 5%, > 50%) of tumor cells with membranous PD-L1 expression or as the percentage of positive stroma cells and associated inflammatory infiltrates. We also assessed the interplay between stromal PD-1/PD-L1 and both intratumoral and stromal CD8 count and their impact on outcome. The primary end point was OS. RESULTS: Stromal PD-L1 and PD-1 expression were both associated with less aggressive tumor behavior in colon cancer patients, which translated into better OS and disease-free survival, respectively. Conversely, PD-L1 staining in the tumor cells was less frequent than stromal staining and was associated with features of aggressive tumor biology, although without impact on outcome. Interestingly, the PD-L1 staining pattern remained similar between primary tumors and corresponding liver metastases. Stromal PD-1 expression correlated significantly with stromal PD-L1 staining and both intratumoral and stromal CD8 expression. CONCLUSION: Stromal PD-1/PD-L1 expression might serve as a prognostic marker in colon cancer patients.