PTPN2 and TiO2 in the pathogenesis of Inflammatory Bowel Disease  

Aim of the research

Titanium dioxide (TiO2) may play a pivotal role in the onset and perpetuation of chronic intestinal inflammation. These effects may be genetically triggered, and variations in IBD risk genes, such as PTPN2, may contribute critically to the detrimental effect of TiO2 in vivo. For these reasons, we will study the combined effects of the presence of disease-associated genetic PTPN2 variations and TiO2 microparticles on the development of chronic intestinal inflammation and on inflammasome activity, as well as the subsequent consequences for the host immune system, in particular innate immune responses. The study will demonstrate the relevance of TiO2 in the pathogenesis of intestinal inflammation in vivo. To address the aforementioned aims, we will:

1. Analyse whether PTPN2-mediated inflammasome activation can control TiO2-induced intestinal inflammation.
2. Demonstrate whether the presence of the disease-associated PTPN2 variant affects NLRP3 inflammasome activation and intestinal inflammatory responses to TiO2 in IBD patients.

Janneke van der Woude © ECCO

During the ECCO’19 Copenhagen Congress the Scientific Committee cordially welcomed Marc Ferrante as a new member.

Marc Ferrante has been an individual member of ECCO since 2008 and has contributed to several ECCO Activities and Initiatives. He was one of the Y-ECCO Founders and Y-ECCO Chairs. His career in ECCO continued in 2015 with a position on ClinCom, and he subsequently became chair of this committee in 2017. 

Sebastian Zeissig © ECCO

Mechanisms and therapeutic modulation of mucosal healing in IBD 

We saw one of the best-ever attended SciCom Workshops this year, with exciting talks and highly interactive discussions around the topic of mucosal healing in IBD. In two sessions, the mechanisms of intestinal regeneration and its disruption in IBD and novel approaches to the clinical assessment and therapeutic modulation of mucosal healing were discussed.

Janneke van der Woude © ECCO

One of the main goals of ECCO is to promote IBD-related basic and clinical research as well as to foster interaction and productive collaboration among European research groups working in the IBD field.

To achieve this goal, ECCO continues to award Grants, Fellowships and Travel Awards, and the number of awardees has now increased to an amazing total of more than 25.  

Definition of IBD-associated gut virome via next-generation sequencing: Novel insights for disease onset and treatments

Federica Ungaro © Federica Ungaro

Aim of Research

Viral infections have been reported to be the primary trigger in many diseases. Preliminary results from RNA-seq analysis performed on mucosal biopsies of patients with active Crohn’s Disease (CD) or Ulcerative Colitis (UC) and healthy controls revealed indicated an IBD-specific viral signature, characterised by increased levels of viral RNAs, especially in patients with UC.

Although analyses on gut virome composition are available, to date nobody has described which viruses are involved in IBD onset. We propose characterising the viral composition of gut mucosal samples from early-diagnosed patients with IBD and healthy subjects by exploiting transcriptomic analysis. Moreover, through RNA silencing experiments, we will investigate whether the inhibition of viral-specific RNAs may be beneficial in mucosal biopsies from patients with active IBD. Results obtained from this study are expected to lead to the unveiling of a novel concept depicting IBD aetiopathogenesis as related to specific viral infections. This will arguably offer new therapeutic insights and promote the search for antiviral drugs for the treatment of IBD.

Identification of the functional role of NLRP6 in human Crohn’s Disease

Dina Danso-Abeam © Dina Danso-Abeam

Aim of Research

The introduction of biological therapies such as anti-TNF has led to a decrease in surgery in IBD. However, many patients do not benefit from this treatment: One-third of patients do not respond to induction therapy (primary non-responders) and about half of primary responders lose response over time (secondary non-responders). This is in part due to therapeutic targeting of generalised inflammation rather than specific targeting of well-defined molecular mediators of IBD pathogenesis.

Most recently, the nod-like receptor NLRP6 has come to light for its potential role in local inflammation driven by gut microbial dysbiosis, albeit almost all data are emerging from mouse models. Our preliminary data from a patient harbouring a novel NLRP6 mutation show significant dysregulation in multiple immune cells, providing strong evidence for the role of NLRP6 in immune homeostasis. Taking into account the high expression of NLRP6 in human intestine, this project aims to decipher the role of NLRP6 in the pathology of Crohn’s Disease (CD).

Neuro-immune interactions in gut macrophages

Holm Uhlig © Holm Uhlig

Inflammatory Bowel Diseases (Crohn’s Disease and Ulcerative Colitis) are polygenic and multifactorial disorders caused by aberrant responses to the intestinal microbiota. Crohn’s Disease in particular is associated with defective bacterial handling in phagocytes (i.e. monocytes and macrophages), which digest bacteria by the process known as autophagy/xenophagy. Monocyte/macrophage function is modulated by the surrounding microenviroment, in which pathogens, metabolites, chemokines and cytokines are present.

Identification of rare genetic variants contributing to the development of childhood-onset IBD-PSC using parent-offspring trios

Patrick van Rheenen © Patrick van Rheenen

Primary Sclerosing Cholangitis (PSC) is a rare and severe disease leading to fibrotic destruction of the bile ducts. The majority of childhood-onset cases are associated with Inflammatory Bowel Disease, Ulcerative Colitis in particular.

TIGIT+CD38+ effector cells: New players in suppressing inflammation in IBD?

Janneke N. Samsom  © Janneke N. Samsom

Background and Hypothesis

In Inflammatory Bowel Disease (IBD), T-cell reactivity against harmless microbial antigens drives chronic inflammation. After induction of remission, patients receive T-cell-suppressing maintenance treatment, which is effective in maintaining remission in some patients but not others. “T-cell immunoglobulin and ITIM domain” (TIGIT) is a novel inhibitor of T-cell activation. Preliminary experiments show that human circulating TIGIT-expressing CD38+ effector T cells are concomitantly enriched in the inhibitory molecules IL-10, PD-1 and CTLA-4. Crucially, frequencies of these cells were much reduced in a subgroup of paediatric IBD patients at disease onset and associated with reduced duration of clinical remission during follow-up.

We hypothesise that TIGIT+CD38+ effector T cells are functionally involved in immune regulation of microbial responses in the gastrointestinal tract.

Regulation of intestinal epithelial homeostasis by Cyclin Y

Stefan Koch © Stefan Koch

Aim of Research

Genetic predisposition contributes to the development of Inflammatory Bowel Diseases (IBD). Prior GWAS studies have identified numerous IBD risk loci, but most of them have no assigned function to date. The aim of this study is to explore the role of the IBD risk gene CCNY, encoding the Wnt signalling activator Cyclin Y, in intestinal homeostasis and wound repair.

Because Wnt signalling is essential for the maintenance of intestinal epithelial stem cells, we anticipate that CCNY mutations impair intestinal Wnt signalling and thereby reduce epithelial regeneration during colitis.