News & Views in 2020

The enteric nervous system (ENS) is an important component of gastrointestinal function and a pivotal hub connecting the gut to other organs. A new study now explores the human and mouse ENS at the single-cell level, providing key insights into the transcriptomic landscape of the ENS and its constituent cells.

A new study sheds further light on the interplay between environmental stimuli, the gut microbiota and intestinal inflammation. Identification of modifiable environmental triggers and the mechanisms by which they act has implications for the prevention and treatment of inflammatory bowel disease.

Liver biopsy sample evaluation is an essential part of clinical studies in nonalcoholic steatohepatitis (NASH) and is key in excluding confounding morbidities. Current scoring systems, which are decisive for study inclusion, rely on imprecisely defined histological features, leading to a high observer variability of disease categorization. In this News & Views, measures to overcome these limitations are discussed.

Vagus nerve stimulation has shown promise in treating inflammatory bowel disease. A new study identifies a hepatic vagal branch pathway necessary to maintain colonic immune cell homeostasis in experimental colitis, challenging the dogma that an anti-inflammatory reflex requires an intact spleen and that α7-nicotinic receptor agonists are a panacea for inflammatory conditions.

Pancreatic cancer is notorious for its affinity for invading nerves. A new study using a systematic unbiased RNA-interference screen of neuronal chemokines in cocultures of mouse sensory neurons and pancreatic cancer cells has now identified CCL21 and CXCL10 as key mediators of neural invasion, neural remodelling and pain in pancreatic cancer.

Most patients who undergo curative intent surgery for pancreatic cancer will still die of recurrent disease. A new study shows that pancreatic tumours that pass through the genetic bottlenecks of surgery and additional chemoradiotherapy have altered mutational signatures, driver genes and subclonal architecture.

A mountable ‘smart’ toilet system has been developed to personalize health monitoring. The system uses excretion data, including urinalysis, urodynamics, stool form and defecation timing, stored in a cloud server. This smart toilet system has the potential to provide useful information to characterize symptoms of patients with bowel dysfunction or defecatory disorders.

Obesity is a known risk factor for pancreatic cancer. Now, a new study reports that obesity accelerates early pancreatic cancer development and growth in mice through local perturbations in the pancreatic microenvironment and implicates pancreatic islet-derived cholecystokinin as a driving factor.

Two new position papers convincingly propose that nonalcoholic fatty liver disease needs a new name — metabolic associated fatty liver disease (MAFLD). A new name for this disease affecting nearly one billion people globally is overdue, as knowledge gained from the past decades has assuringly demonstrated that MAFLD is a purely metabolic disorder.

Details about IgE-producing B cells in the gut in the context of food allergy are scarce, despite the frequent exposure of the gut and its associated lymphoid tissues to dietary antigens. A new study finds that IgE-producing B cells are enriched in gut tissues and are probably generated from local antibody isotype switching.

New national hepatitis C virus (HCV) screening guidance from the United States Preventive Services Task Force includes a recommendation for one-time testing for all adults aged 18 to 79 years. Implicit in the new guidance is that all people diagnosed with chronic HCV infection should be offered HCV treatment.

The microbial communities that occupy the intestinal tract are shaped by a variety of different factors, including the immune system. A new study has observed and quantified, at unprecedented depth, regionally distinct microbial and immune niches along the human colon using simultaneous analyses of the gut microbiota and neighbouring immune cells.

Colibactin-producing bacteria are abundant in the gut microbiota of colorectal cancer tumours and promote colon tumorigenesis in mouse models. Now, a new study demonstrates a direct link between exposure of human intestinal epithelial cells to colibactin and two unique mutational fingerprints found in human colorectal tumours.

Genomic alterations are well-described in Barrett oesophagus and its sequela, oesophageal adenocarcinoma, but epigenomic events have not been so widely investigated. In a new study, Jammula et al. analysed the DNA methylation profiles of Barrett oesophagus, oesophageal adenocarcinoma and control tissues. Four molecular subtypes were identified, revealing four distinct epigenomic classes and potential therapeutic targets.

In a new study, cryopreserved human hepatocytes retrieved from livers deemed unsuitable for transplantation were thawed and encapsulated into alginate microbeads and then infused into the peritoneal cavity of a group of children with acute liver failure who were awaiting liver transplantation.

Faecal microbiota transplantation (FMT) aims to restore an altered microbiota and has been suggested as a potential treatment option for irritable bowel syndrome (IBS), among other diseases. A new study suggests that the use of a so-called superdonor is necessary to successfully treat patients with IBS using FMT.

A novel MRI gadolinium-based contrast agent designed to bind with collagen, a key component in liver fibrosis progression, provides direct quantification of collagen deposition in several preclinical liver disease models. This tool could have large implications in clinical diagnosis and drug trials.

Cancer therapies, in addition to inducing cell death, can trigger cellular senescence of tumour cells, and factors secreted from senescent cells might negatively affect the tumour microenvironment. A new study by Wang et al. shows that eradication of therapy-induced senescent cells (senolysis) can improve the outcome of liver cancer therapy.

A new study has identified an intestinal stem cell population involved in epithelial regeneration upon injury in mice and provided an in vitro tool with which to characterize the recurrent damage–repair mechanisms affecting chronic gastrointestinal inflammatory disorders, including inflammatory bowel disease.