Local immune regulation of mucosal inflammation by tacrolimus

Purpose: Tacrolimus is a potent immunomodulator that is effective in the treatment of inflammatory bowel disease (IBD). However, potential toxicity and systemic effects with oral intake limit its use. Local tacrolimus treatment is effective in a subgrou

A standardised model for stool banking for faecal microbiota transplantation : a consensus report from a multidisciplinary UEG working group

Background Faecal microbiota transplantation is an emerging therapeutic option, particularly for the treatment of recurrent Clostridioides difficile infection. Stool banks that organise recruitment and screening of faeces donors are being embedded within the regulatory frameworks described in the European Union Tissue and Cells Directive and the technical guide to the quality and safety of tissue and cells for human application, published by the European Council. Objective Several European and international consensus statements concerning faecal microbiota transplantation have been issued. While these documents provide overall guidance, we aim to provide a detailed description of all processes that relate to the collection, handling and clinical application of human donor stool in this document. Methods Collaborative subgroups of experts on stool banking drafted concepts for all domains pertaining to stool banking. During a working group meeting in the United European Gastroenterology Week 2019 in Barcelona, these concepts were discussed and finalised to be included in our overall guidance document about faecal microbiota transplantation. Results A guidance document for all domains pertaining to stool banking was created. This document includes standard operating manuals for several processes involved with stool banking, such as handling of donor material, storage and donor screening. Conclusion The implementation of faecal microbiota transplantation by stool banks in concordance with our guidance document will enable quality assurance and guarantee the availability of donor faeces preparations for patients.Peer reviewe

Cytotoxic and Pathogenic Properties of Klebsiella oxytoca Isolated from Laboratory Animals

Klebsiella oxytoca is an opportunistic pathogen implicated in various clinical diseases in animals and humans. Studies suggest that in humans K. oxytoca exerts its pathogenicity in part through a cytotoxin. However, cytotoxin production in animal isolates of K. oxytoca and its pathogenic properties have not been characterized. Furthermore, neither the identity of the toxin nor a complete repertoire of genes involved in K. oxytoca pathogenesis have been fully elucidated. Here, we showed that several animal isolates of K. oxytoca, including the clinical isolates, produced secreted products in bacterial culture supernatant that display cytotoxicity on HEp-2 and HeLa cells, indicating the ability to produce cytotoxin. Cytotoxin production appears to be regulated by the environment, and soy based product was found to have a strong toxin induction property. The toxin was identified, by liquid chromatography-mass spectrometry and NMR spectroscopy, as low molecular weight heat labile benzodiazepine, tilivalline, previously shown to cause cytotoxicity in several cell lines, including mouse L1210 leukemic cells. Genome sequencing and analyses of a cytotoxin positive K. oxytoca strain isolated from an abscess of a mouse, identified genes previously shown to promote pathogenesis in other enteric bacterial pathogens including ecotin, several genes encoding for type IV and type VI secretion systems, and proteins that show sequence similarity to known bacterial toxins including cholera toxin. To our knowledge, these results demonstrate for the first time, that animal isolates of K. oxytoca, produces a cytotoxin, and that cytotoxin production is under strict environmental regulation. We also confirmed tilivalline as the cytotoxin present in animal K. oxytoca strains. These findings, along with the discovery of a repertoire of genes with virulence potential, provide important insights into the pathogenesis of K. oxytoca. As a novel diagnostic tool, tilivalline may serve as a biomarker for K oxytoca-induced cytotoxicity in humans and animals through detection in various samples from food to diseased samples using LC-MS/MS. Induction of K. oxytoca cytotoxin by consumption of soy may be in part involved in the pathogenesis of gastrointestinal disease