Significant differences in IBD care and education across Europe: results of the pan-European VIPER survey.

BACKGROUND: Inflammatory bowel disease (IBD) care and education might differ around Europe. Therefore, we conducted this European Variation In IBD PracticE suRvey (VIPER) to investigate potential differences between countries. METHODS: This trainee-initiated survey, run through SurveyMonkey®, consisted of 47 questions inquiring basic demographics, IBD training, and clinical care. Results were compared according to gross domestic product (GDP) per capita, for which countries were divided into 2 groups (low/high income, according to the World Bank). RESULTS: The online survey was completed by 1285 participants from 40 European countries, with a majority of specialists (65.3%) working in academic institutions (50.4%). Significant differences in IBD-specific training (55.9% vs. 38.4%), as well as availability of IBD units (58.4% vs. 39.7%) and multidisciplinary meetings (73.2% vs. 40.1%) were observed between respondees from high and low GDP countries (p<0.0001). In high GDP countries, IBD nurses are more common (85.9% vs. 36.0%), also mirrored by more nurse-led IBD clinics (40.6% vs. 13.7%; p<0.0001). IBD dieticians (33.4% vs. 16.5%) and psychologists (16.8% vs. 7.5%) are mainly present in high GDP countries (p<0.0001). In the current COVID era, telemedicine is available in 73.2% vs. 54.1% of the high/low GDP countries respectively (p<0.0001). Treat-to-target approaches are implemented everywhere (85.0%), though access to biologicals and small molecules differs significantly. CONCLUSION: Much variability in IBD practice exists across Europe, with marked differences between high vs. low GDP countries. Further work is required to help address some of these inequalities, aiming to improve and standardize IBD care and training across Europe.

Mapping the epithelial-immune cell interactome upon infection in the gut and the upper airways.

Increasing evidence points towards the key role of the epithelium in the systemic and over-activated immune response to viral infection, including SARS-CoV-2 infection. Yet, how viral infection alters epithelial-immune cell interactions regulating inflammatory responses, is not well known. Available experimental approaches are insufficient to properly analyse this complex system, and computational predictions and targeted data integration are needed as an alternative approach. In this work, we propose an integrated computational biology framework that models how infection alters intracellular signalling of epithelial cells and how this change impacts the systemic immune response through modified interactions between epithelial cells and local immune cell populations. As a proof-of-concept, we focused on the role of intestinal and upper-airway epithelial infection. To characterise the modified epithelial-immune interactome, we integrated intra- and intercellular networks with single-cell RNA-seq data from SARS-CoV-2 infected human ileal and colonic organoids as well as from infected airway ciliated epithelial cells. This integrated methodology has proven useful to point out specific epithelial-immune interactions driving inflammation during disease response, and propose relevant molecular targets to guide focused experimental analysis.

Intestinal Receptor of SARS-CoV-2 in Inflamed IBD Tissue Seems Downregulated by HNF4A in Ileum and Upregulated by Interferon Regulating Factors in Colon.

BACKGROUND: Patients with inflammatory bowel disease [IBD] are considered immunosuppressed, but do not seem more vulnerable for COVID-19. Nevertheless, intestinal inflammation has shown to be an important risk factor for SARS-CoV-2 infection and prognosis. Therefore, we investigated the role of intestinal inflammation on the viral intestinal entry mechanisms, including ACE2, in IBD. METHODS: We collected inflamed and uninflamed mucosal biopsies from Crohn's disease [CD] [n = 193] and ulcerative colitis [UC] [n = 158] patients, and from 51 matched non-IBD controls for RNA sequencing, differential gene expression, and co-expression analysis. Organoids from UC patients were subjected to an inflammatory mix and processed for RNA sequencing. Transmural ileal biopsies were processed for single-cell [sc] sequencing. Publicly available colonic sc-RNA sequencing data, and microarrays from tissue pre/post anti-tumour necrosis factor [TNF] therapy, were analysed. RESULTS: In inflamed CD ileum, ACE2 was significantly decreased compared with control ileum [p = 4.6E-07], whereas colonic ACE2 was higher in inflamed colon of CD/UC compared with control [p = 8.3E-03; p = 1.9E-03]. Sc-RNA sequencing confirmed this ACE2 dysregulation and exclusive epithelial ACE2 expression. Network analyses highlighted HNF4A as key regulator of ileal ACE2, and pro-inflammatory cytokines and interferon regulating factors regulated colonic ACE2. Inflammatory stimuli upregulated ACE2 in UC organoids [p = 1.7E-02], but not in non-IBD controls [p = 9.1E-01]. Anti-TNF therapy restored colonic ACE2 regulation in responders. CONCLUSIONS: Intestinal inflammation alters SARS-CoV-2 coreceptors in the intestine, with opposing dysregulations in ileum and colon. HNF4A, an IBD susceptibility gene, seems an important upstream regulator of ACE2 in ileum, whereas interferon signalling might dominate in colon.