Effect of Fecal Microbiota Transplantation on 8-Week Remission in Patients With Ulcerative Colitis: A Randomized Clinical Trial

Improving Risk-Benefit in Faecal Transplantation through Microbiome Screening

Faecal microbiota transplantation (FMT) has been shown to be effective in the treatment of a growing number of conditions, and its clinical use continues to rise. However, recent cases of antibiotic-resistant pathogen transmission through FMT, resulting in at least one case of fatal sepsis, highlight the need to reevaluate current donor screening practices. Commensal gut microbes profoundly influence infection risk but are not routinely assessed in donor stool. Extending the assessment of donor material beyond pathogen populations to include the composition and structure of the wider faecal microbiota has the potential to reduce infectious complications in FMT recipients.

Gut Microbiota and Alimentary Tract Injury

The gastrointestinal (GI) tract is inhabited by a diverse array of microbes, which play crucial roles in health and disease. Dysbiosis of microbiota has been tightly linked to gastrointestinal inflammatory and malignant diseases. Here we highlight the role of Helicobacter pylori alongside gastric microbiota associated with gastric inflammation and cancer. We summarize the taxonomic and functional aspects of intestinal microbiota linked to inflammatory bowel diseases (IBD), irritable bowel syndrome (IBS), and colorectal cancer in clinical investigations. We also discuss microbiome-related animal models. Nevertheless, there are tremendous opportunities to reveal the causality of microbiota in health and disease and detailed microbe-host interaction mechanisms by which how dysbiosis is causally linked to inflammatory disease and cancer, in turn, potentializing clinical interventions with a personalized high efficacy.

Interrogating host immunity to predict treatment response in inflammatory bowel disease

IBD treatment is undergoing a transformation with an expanding repertoire of drugs targeting different aspects of the immune response. Three novel classes of drugs have emerged in the past decade that target leukocyte trafficking to the gut (vedolizumab), neutralize key cytokines with antibodies (ustekinumab) and inhibit cytokine signalling pathways (tofacitinib). In advanced development are other drugs for IBD, including therapies targeting other cytokines such as IL-23 and IL-6. However, all agents tested so far are hampered by primary and secondary loss of response, so it is desirable to develop personalized strategies to identify which patients should be treated with which drugs. Stratification of patients with IBD by clinical parameters alone lacks sensitivity, and alternative modalities are now needed to deliver precision medicine in IBD. High-resolution profiling of immune response networks in individual patients is a promising approach and different technical platforms, including in vivo real-time molecular endoscopy, tissue transcriptomics and germline genetics, are promising tools to help predict responses to specific therapies. However, important challenges remain regarding the clinical utility of these technologies, including their scalability and accessibility. This Review focuses on unravelling some of the complexity of mucosal immune responses in IBD pathogenesis and how current and emerging analytical platforms might be harnessed to effectively stratify and individualise IBD therapy.

Scientific frontiers in faecal microbiota transplantation: joint document of Asia-Pacific Association of Gastroenterology (APAGE) and Asia-Pacific Society for Digestive Endoscopy (APSDE)

OBJECTIVE

The underlying microbial basis, predictors of therapeutic outcome and active constituent(s) of faecal microbiota transplantation (FMT) mediating benefit remain unknown. An international panel of experts presented key elements that will shape forthcoming FMT research and practice.

DESIGN

Systematic search was performed, FMT literature was critically appraised and a 1-day round-table discussion was conducted to derive expert consensus on key issues in FMT research.

RESULTS

16 experts convened and discussed five questions regarding (1) the role of donor and recipient microbial (bacteria, viruses, fungi) parameters in FMT; (2) methods to assess microbiota alterations; (3) concept of keystone species and microbial predictors of FMT, (4) influence of recipient profile and antibiotics pretreatment on FMT engraftment and maintenance and (5) new developments in FMT formulations and delivery. The panel considered that variable outcomes of FMT relate to compositional and functional differences in recipient's microbiota, and likely donor-associated and recipient-associated physiological and genetic factors. Taxonomic composition of donor intestinal microbiota may influence the efficacy of FMT in recurrent Clostridioides difficile infections and UC. FMT not only alters bacteria composition but also establishes trans-kingdom equilibrium between gut fungi, viruses and bacteria to promote the recovery of microbial homeostasis. FMT is not a one size fits all and studies are required to identify microbial components that have specific effects in patients with different diseases.

CONCLUSION

FMT requires optimisation before their therapeutic promise can be evaluated for different diseases. This summary will guide future directions and priorities in advancement of the science and practice of FMT.

The future of faecal microbiota transplantation in gastrointestinal illness

The gut microbiome is made up of hundreds of trillions of microorganisms that reside in a state of homeostatic balance within the healthy individual. Next generation sequencing has provided insight into the diversity of these microorganisms that reside within our gastrointestinal tract; despite developments in metabolomics and culturing techniques, the functions of many of these bacteria remain largely elusive. As such, research into the capacity of the gut microbiome to regulate immune homeostasis has revealed the importance of bacteria in human health, with the potential for exploiting these bacteria only now coming into focus.

Expert opinion on fecal microbiota transplantation for the treatment of Clostridioides difficile infection and beyond

Introduction: Fecal microbiota transplantation (FMT) is a procedure involving transfer of stool from a healthy donor into the intestinal tract of a diseased recipient to restore intestinal microbial composition and functionality. FMT's tremendous success in recurrent and refractory Clostridioides difficile infection (CDI) catalyzed gut microbiota research and opened the door to microbiome-based therapy for various gastrointestinal and other disorders.Areas covered: We used PubMed search engine to identify significant publications in the field of CDI and FMT. Here we present an overview of the current literature on FMT's use for recurrent, non-severe, severe, and fulminant CDI and on promising future application.Expert opinion: FMT as the best tool for treatment of antibiotic-refractory CDI has gained immense popularity over the last decade. The future of gut microbiota-based therapy should include oral formulations that contain well-described ingredients in effective doses, clear mechanism of action, and excellent safety profile.

A new treatment for ulcerative colitis: Intracolonic Bifidobacterium and xyloglucan application

Ulcerative colitis (UC) pathogenesis includes the altered gut microbiota, environmental factors, and human immune and genetic predisposition. Recently, its association with reduced bifidobacteria quantity in the microbiota is reported. Xyloglucan, a plant-based prebiotic oligosaccharide, causes increase in bifidobacteria quantity. In this article, we share the results of our UC cases treated by intracolonic single-dose administration of Bifidobacterium animalis subsp. lactis and xyloglucan combination. Intracolonic single-dose administration of 200 billion colony-forming units (CFUs) of B. animalis subsp. lactis and 4 g of xyloglucan combination was administrated to 10 severe UC patients, who were either unresponsive or had inadequate response to treatment. All patients continued treatment after the procedure. Treatment responses were evaluated by colonoscopic, laboratory, and clinical examination after 6 weeks. Intracolonic single-dose administration of B. animalis subsp. lactis and xyloglucan was found effective in the mucosal healing and resolution of colonic symptoms in UC patients. Intracolonic administration of B. animalis subsp. lactis and xyloglucan in UC is a new single-strain and strain-specific prebiotic combination method. It is easy to apply and has no observable side effect. Its effectiveness on mucosal healing could be attributed to the enhancement of non-stimulatory status and biodiversity in colonic mucosa. Nonetheless, it is still necessary to develop diagnostic strategies to determine the patients to whom this method would be the most applicable.

Mesenchymal stem cell-gut microbiota interaction in the repair of inflammatory bowel disease: an enhanced therapeutic effect

BACKGROUND

Several investigations affirm that, patients with inflammatory bowel disease (IBD) exhibit dysbiosis characterized by restricted biodiversity and imbalanced bacterial composition intertwined with immune dysregulation. The interaction between stem cells and gut microbiota is a novel and highly promising field that could add up to a better understanding of the gut physiology, as well as therapeutic improvement towards diseases like IBD. Through direct contact or release of products and/or metabolites, gut bacteria regulate gut homeostasis, damage repair, regeneration and differentiation of stem cells. In the same way, mesenchymal stem cells (MSCs) produce similar effects including restoration of gut-microbiome composition. BODY: We reviewed the anti-inflammatory, antimicrobial, pathogenic bacterial clearance, proliferation and tissue remodeling effects of mesenchymal stem cells (MSCs) and fecal microbiota transplantation (FMT) as separate transplants in IBD, and the outcome of the interaction between MSCs and gut microbiota.

CONCLUSION

The two therapies share several points of connection in therapeutics with enhanced functionalities in their interaction with each other. Focused investigations of MSC-gut bacteria interactions could lead to a novel discovery in therapeutics. We also anticipate an improved clinical remission rate in a combined FMT-MSC transplantation approach in IBD than the current single FMT or MSC approach.

International consensus conference on stool banking for faecal microbiota transplantation in clinical practice

Although faecal microbiota transplantation (FMT) has a well-established role in the treatment of recurrent Clostridioides difficile infection (CDI), its widespread dissemination is limited by several obstacles, including lack of dedicated centres, difficulties with donor recruitment and complexities related to regulation and safety monitoring. Given the considerable burden of CDI on global healthcare systems, FMT should be widely available to most centres.Stool banks may guarantee reliable, timely and equitable access to FMT for patients and a traceable workflow that ensures safety and quality of procedures. In this consensus project, FMT experts from Europe, North America and Australia gathered and released statements on the following issues related to the stool banking: general principles, objectives and organisation of the stool bank; selection and screening of donors; collection, preparation and storage of faeces; services and clients; registries, monitoring of outcomes and ethical issues; and the evolving role of FMT in clinical practice,Consensus on each statement was achieved through a Delphi process and then in a plenary face-to-face meeting. For each key issue, the best available evidence was assessed, with the aim of providing guidance for the development of stool banks in order to promote accessibility to FMT in clinical practice.

Alternative & complementary treatment for pediatric inflammatory bowel disease

Alternative medicine includes treatments that are not considered mainstream and is suggested to replace the accepted treatment, while complementary treatment is added to the conventional treatment. The estimated prevalence of their use in patients with inflammatory bowel disease (IBD) is high, ranging between 21-60%. This review summarizes the data on these treatments and their efficacy in the setting of IBD.

British Society of Gastroenterology consensus guidelines on the management of inflammatory bowel disease in adults

Ulcerative colitis and Crohn's disease are the principal forms of inflammatory bowel disease. Both represent chronic inflammation of the gastrointestinal tract, which displays heterogeneity in inflammatory and symptomatic burden between patients and within individuals over time. Optimal management relies on understanding and tailoring evidence-based interventions by clinicians in partnership with patients. This guideline for management of inflammatory bowel disease in adults over 16 years of age was developed by Stakeholders representing UK physicians (British Society of Gastroenterology), surgeons (Association of Coloproctology of Great Britain and Ireland), specialist nurses (Royal College of Nursing), paediatricians (British Society of Paediatric Gastroenterology, Hepatology and Nutrition), dietitians (British Dietetic Association), radiologists (British Society of Gastrointestinal and Abdominal Radiology), general practitioners (Primary Care Society for Gastroenterology) and patients (Crohn's and Colitis UK). A systematic review of 88 247 publications and a Delphi consensus process involving 81 multidisciplinary clinicians and patients was undertaken to develop 168 evidence- and expert opinion-based recommendations for pharmacological, non-pharmacological and surgical interventions, as well as optimal service delivery in the management of both ulcerative colitis and Crohn's disease. Comprehensive up-to-date guidance is provided regarding indications for, initiation and monitoring of immunosuppressive therapies, nutrition interventions, pre-, peri- and postoperative management, as well as structure and function of the multidisciplinary team and integration between primary and secondary care. Twenty research priorities to inform future clinical management are presented, alongside objective measurement of priority importance, determined by 2379 electronic survey responses from individuals living with ulcerative colitis and Crohn's disease, including patients, their families and friends.

Microbiota modulation-based therapy for luminal GI disorders: current applications of probiotics and fecal microbiota transplantation

Introduction: Alteration in the intestinal microbiota also termed as intestinal dysbiosis has been demonstrated in numerous gastrointestinal disorders linked to aberrant immune processes, acquisition of pathogenic organisms and often administration of antibiotics. Restoration of microbiota through probiotics and fecal microbiota transplantation (FMT) has gained tremendous popularity among researchers in the prevention and treatment of gastrointestinal diseases.Areas covered: In this review, studies testing the safety and efficacy of probiotics and FMT for the treatment of various infectious and inflammatory luminal gastrointestinal diseases are reviewed. Randomized control studies are given priority while important uncontrolled studies are also highlighted.Expert opinion: Probiotics have demonstrated efficacy in the prevention of antibiotic-associated diarrhea and in the eradication of Helicobacter pylori infection. Their utility in the primary and secondary prevention of Clostridioides difficile infection is debatable. The future of medicine should bring forth a personalized approach to probiotic use. FMT has revolutionized the treatment of recurrent CDI as well as severe and fulminant CDI. At the same time, it has galvanized gut microbiota research in the last decade. While FMT in ulcerative colitis appears promising, further studies on the durability and long-term safety are needed before it can be recommended in clinical practice.

The Gut Microbiome in Inflammatory Bowel Diseases: Diagnostic and Therapeutic Implications

The incidence of chronic inflammatory bowel diseases (IBD) is rising worldwide, and the interaction between the mucosal immune system and the intestinal microbiota is crucial for the understanding of these diseases. Due to new technologies, the data published on the intestinal microbiota has increased rapidly in the recent years. While many findings are descriptive, reporting associations between disease and microbial populations, recent advancement in technology made it possible to ask and answer more functional questions and to elucidate complex interactions between the intestinal microbiota and the mucosal immune system. In addition, first trials influenced the intestinal microbiota with the intention to treat IBD. This review summarizes aspects of the physiological function as well as the inflammation-induced changes of the gut microbiota and the association between the gut microbiota and pathogenesis in IBD. In addition, diagnostic and therapeutic options for treating IBD are reviewed.

Fecal microbiota transplantation as a new therapy: from Clostridioides difficile infection to inflammatory bowel disease, irritable bowel syndrome, and colon cancer

Fecal microbiota transplantation (FMT) represents the most effective means of therapeutically manipulating the gastrointestinal microbiome. Originally employed as a treatment of last-resort in patients with life-threatening Clostridioides difficile infection (CDI), FMT gained widespread acceptance during the CDI epidemic, where it achieved resolution rates approaching 100%. Following our newfound appreciation for the role of the gut microbiome in both health and disease and owing to FMT's unique mechanism/s of action, FMT is rapidly advancing as an effective treatment for a number of conditions in which the gastrointestinal microbiome is thought to play a role. We review the role of FMT from its beginnings in CDI to its expansion into inflammatory bowel disease, irritable bowel syndrome, and colon cancer.

British Society of Gastroenterology consensus guidelines on the management of inflammatory bowel disease in adults

Ulcerative colitis and Crohn's disease are the principal forms of inflammatory bowel disease. Both represent chronic inflammation of the gastrointestinal tract, which displays heterogeneity in inflammatory and symptomatic burden between patients and within individuals over time. Optimal management relies on understanding and tailoring evidence-based interventions by clinicians in partnership with patients. This guideline for management of inflammatory bowel disease in adults over 16 years of age was developed by Stakeholders representing UK physicians (British Society of Gastroenterology), surgeons (Association of Coloproctology of Great Britain and Ireland), specialist nurses (Royal College of Nursing), paediatricians (British Society of Paediatric Gastroenterology, Hepatology and Nutrition), dietitians (British Dietetic Association), radiologists (British Society of Gastrointestinal and Abdominal Radiology), general practitioners (Primary Care Society for Gastroenterology) and patients (Crohn's and Colitis UK). A systematic review of 88 247 publications and a Delphi consensus process involving 81 multidisciplinary clinicians and patients was undertaken to develop 168 evidence- and expert opinion-based recommendations for pharmacological, non-pharmacological and surgical interventions, as well as optimal service delivery in the management of both ulcerative colitis and Crohn's disease. Comprehensive up-to-date guidance is provided regarding indications for, initiation and monitoring of immunosuppressive therapies, nutrition interventions, pre-, peri- and postoperative management, as well as structure and function of the multidisciplinary team and integration between primary and secondary care. Twenty research priorities to inform future clinical management are presented, alongside objective measurement of priority importance, determined by 2379 electronic survey responses from individuals living with ulcerative colitis and Crohn's disease, including patients, their families and friends.

Immunological mechanisms underpinning faecal microbiota transplantation for the treatment of inflammatory bowel disease

Inflammatory bowel disease (IBD) is a chronic gastrointestinal disease that results from a dysregulated immune response against specific environmental triggers in a genetically predisposed individual. Increasing evidence has indicated a causal role for changes in gut microbiota (dysbiosis) contributing to this immune-mediated intestinal inflammation. These mechanisms involve dysregulation of multiple facets of the host immune pathways that are potentially reversible. Faecal microbiota transplantation (FMT) is the transfer of processed stool from a healthy donor into an individual with an illness. FMT has shown promising results in both animal model experiments and clinical studies in IBD in the resolution of intestinal inflammation. The underlying mechanisms, however, are unclear. Insights from these studies have shown interactions between modulation of dysbiosis via changes in abundances of specific members of the gut microbial community and changes in host immunological pathways. Unravelling these causal relationships has promising potential for a translational therapy role to develop targeted microbial therapies and understand the mechanisms that underpin IBD aetiopathogenesis. In this review, we discuss current evidence for the contribution of gut microbiota in the disruption of intestinal immune homeostasis and immunoregulatory mechanisms that are associated with the resolution of inflammation through FMT in IBD.

Gaps in knowledge and future directions for the use of faecal microbiota transplant in the treatment of inflammatory bowel disease

Faecal microbiota transplant (FMT) has now been established into clinical guidelines for the treatment of recurrent and refractory Clostridioides difficile infection (CDI). Its therapeutic application in inflammatory bowel disease (IBD) is currently at an early stage. To date, there have been four randomized controlled trials for FMT in IBD and a multitude of observational studies. However, significant gaps in our knowledge regarding optimum methods for FMT preparation, technical aspects and logistics of its administration, as well as mechanistic underpinnings, still remain. In this article, we aim to highlight these gaps by reviewing evidence and making key recommendations on the direction of future studies in this field. In addition, we provide an overview of the current evidence of potential mechanisms of FMT in treating IBD.

STOP-Colitis pilot trial protocol: a prospective, open-label, randomised pilot study to assess two possible routes of faecal microbiota transplant delivery in patients with ulcerative colitis

INTRODUCTION

Imbalance of the gut microbiome is key to the pathogenesis of ulcerative colitis (UC). Faecal microbiota transplant (FMT) is the transfer of homogenised and filtered faeces from a healthy individual to the gastrointestinal tract of a patient with disease. Published datasets show a positive signal for the use of FMT to treat UC, but the optimal route and dose of FMT remain unanswered.

METHODS AND ANALYSIS

This prospective, multi-centre open-label, randomised pilot study will assess two possible routes of FMT delivery, via the nasogastric (NG) route or by delivery to the COLON, in 30 patients with active UC recruited from three sites in the UK. Stool will be collected from healthy screened donors, processed, frozen and stored under a Medicines and Healthcare products Regulatory Agency (MHRA) "specials" manufacturing licence held at the University of Birmingham Microbiome Treatment Centre. Thawed FMT samples will be administered to patients either via eight nasogastric infusions given initially over 4 days starting on the day of randomisation, and then again for 4 days in week 4 for foregut delivery (total of 240 g of stool) or via one colonoscopic infusion followed by seven weekly enemas according to the hindgut protocol (total of 360 g of stool). Patients will be followed up weekly for 8 weeks, and then at 12 weeks. The aims of this pilot study are (1) to determine which FMT administration route (NG or COLON) should be investigated in a randomised double-blind, placebo-controlled trial and (2) to determine if a full randomised controlled trial is feasible. The primary outcome will be a composite assessment of both qualitative and quantitative data based on efficacy (clinical response), acceptability and safety. At the end of the pilot study, decisions will be made regarding the feasibility of a full randomised double-blind, placebo-controlled trial and, if deemed feasible, which route of administration should be used in such a study.

ETHICS AND DISSEMINATION

Ethical approval for this study has been obtained from the East Midlands-Nottingham Research Ethics Committee (REC 17/EM/0274). At the end of the study, findings will be reported at national and international gastroenterology meetings and published in peer-reviewed journals.

TRIAL REGISTRATION NUMBER

ISRCTN74072945.

Inflammatory bowel diseases: interrelationships between dietary vitamin D, exposure to UV radiation and the fecal microbiome

Introduction: Environmental factors and an altered fecal microbiome are believed to be central to the pathogenesis of inflammatory bowel diseases (IBD). Vitamin D and ultraviolet radiation (UVR) are environmental factors that are associated by several pathways, including changes to the gastrointestinal microbiome, with the development and course of IBD.Area covered: This review explores the interaction of vitamin D, and UVR, with the intestinal innate and adaptive immune systems, and how they may influence the gut microbiome and the subsequent development, and progression, of IBD.Expert opinion: Vitamin D and UVR both regulate innate and adaptive immunity through a combination of common and independent mechanisms, with the overall effect being the promotion of immune tolerance. Vitamin D, and to a lesser extent UVR, can modify the gastrointestinal microbiome either directly, or through immune-mediated mechanisms and this may explain the effect on intestinal inflammation in animal models of IBD and some clinical studies. Thus, both vitamin D and UVR exposure can be considered potential 'master regulators' of gastrointestinal immunity, fine-tuning the complex interaction between genetics, host immunity and the gut microbiome. Further research and increased understanding of environment-host interactions is essential to achieving the ultimate goal of preventing and curing IBD.

Rescue fecal microbiota transplantation for antibiotic-associated diarrhea in critically ill patients

BACKGROUND

Antibiotic-associated diarrhea (AAD) is a risk factor for exacerbating the outcome of critically ill patients. Dysbiosis induced by the exposure to antibiotics reveals the potential therapeutic role of fecal microbiota transplantation (FMT) in these patients. Herein, we aimed to evaluate the safety and potential benefit of rescue FMT for AAD in critically ill patients.

METHODS

A series of critically ill patients with AAD received rescue FMT from Chinese fmtBank, from September 2015 to February 2019. Adverse events (AEs) and rescue FMT success which focused on the improvement of abdominal symptoms and post-ICU survival rate during a minimum of 12 weeks follow-up were assessed.

RESULTS

Twenty critically ill patients with AAD underwent rescue FMT, and 18 of them were included for analysis. The mean of Acute Physiology and Chronic Health Evaluation (APACHE) II scores at intensive care unit (ICU) admission was 21.7 ± 8.3 (range 11-37). Thirteen patients received FMT through nasojejunal tube, four through gastroscopy, and one through enema. Patients were treated with four (4.2 ± 2.1, range 2-9) types of antibiotics before and during the onset of AAD. 38.9% (7/18) of patients had FMT-related AEs during follow-up, including increased diarrhea frequency, abdominal pain, increased serum amylase, and fever. Eight deaths unrelated to FMT occurred during follow-up. One hundred percent (2/2) of abdominal pain, 86.7% (13/15) of diarrhea, 69.2% (9/13) of abdominal distention, and 50% (1/2) of hematochezia were improved after FMT. 44.4% (8/18) of patients recovered from abdominal symptoms without recurrence and survived for a minimum of 12 weeks after being discharged from ICU.

CONCLUSION

In this case series studying the use of FMT in critically ill patients with AAD, good clinical outcomes without infectious complications were observed. These findings could potentially encourage researchers to set up new clinical trials that will provide more insight into the potential benefit and safety of the procedure in the ICU.

TRIAL REGISTRATION

ClinicalTrials.gov, Number NCT03895593 . Registered 29 March 2019 (retrospectively registered).

A single faecal microbiota transplantation modulates the microbiome and improves clinical manifestations in a rat model of colitis

Background

Faecal microbiota transplantation (FMT) is a novel potential therapy for inflammatory bowel diseases, but it is poorly characterised.

Methods

We evaluated the performance of the mouse and rat as a pre-clinical model for human microbiota engraftment. We then characterised the effect of a single human stool transfer (HST) on a humanised model of DSS-induced colitis. Colonic and faecal microbial communities were analysed using the 16S rRNA approach and clinical manifestations were assessed in a longitudinal setting.

Findings

The microbial community of rats showed greater similarity to that of humans, while the microbiome of mice showed less similarity to that of humans. Moreover, rats captured more human microbial species than mice after a single HST. Using the rat model, we showed that HST compensated faecal dysbiosis by restoring alpha-diversity and by increasing the relative abundance of health-related microbial genera. To some extent, HST also modulated the microbial composition of colonic tissue. These faecal and colonic microbial communities alterations led to a relative restoration of colon length, and a significant decrease in both epithelium damage and disease severity. Remarkably, stopping inflammation by removing DSS before HST caused a faster and greater recovery of both microbiome and clinical manifestation features.

Interpretation

Our results indicate that the rat outperforms the mouse as a model for human microbiota engraftment and show that the efficacy of HST can be enhanced when inflammation stimulation is withdrawn. Finally, our findings support a new therapeutic strategy based on the use FMT combined with anti-inflammatory drugs.

Demystifying the manipulation of host immunity, metabolism, and extraintestinal tumors by the gut microbiome

The trillions of microorganisms in the gut microbiome have attracted much attention recently owing to their sophisticated and widespread impacts on numerous aspects of host pathophysiology. Remarkable progress in large-scale sequencing and mass spectrometry has increased our understanding of the influence of the microbiome and/or its metabolites on the onset and progression of extraintestinal cancers and the efficacy of cancer immunotherapy. Given the plasticity in microbial composition and function, microbial-based therapeutic interventions, including dietary modulation, prebiotics, and probiotics, as well as fecal microbial transplantation, potentially permit the development of novel strategies for cancer therapy to improve clinical outcomes. Herein, we summarize the latest evidence on the involvement of the gut microbiome in host immunity and metabolism, the effects of the microbiome on extraintestinal cancers and the immune response, and strategies to modulate the gut microbiome, and we discuss ongoing studies and future areas of research that deserve focused research efforts.

Transmission and clearance of potential procarcinogenic bacteria during fecal microbiota transplantation for recurrent Clostridioides difficile

BACKGROUNDFecal microbiota transplantation (FMT) is an effective treatment for recurrent Clostridioides difficile infection (rCDI) in adults and children, but donor stool samples are currently screened for only a limited number of potential pathogens. We sought to determine whether putative procarcinogenic bacteria (enterotoxigenic Bacteroides fragilis, Fusobacterium nucleatum, and Escherichia coli harboring the colibactin toxin) could be durably transmitted from donors to patients during FMT.METHODSStool samples were collected from 11 pediatric rCDI patients and their respective FMT donors prior to FMT as well as from the patients at 2-10 weeks, 10-20 weeks, and 6 months after FMT. Bacterial virulence factors in stool DNA extracts and stool cultures were measured by quantitative PCR: Bacteroides fragilis toxin (bft), Fusobacterium adhesin A (fadA), and Escherichia coli colibactin (clbB).RESULTSFour of 11 patients demonstrated sustained acquisition of a procarcinogenic bacteria. Whole genome sequencing was performed on colony isolates from one of these donor/recipient pairs and demonstrated that clbB+ E. coli strains present in the recipient after FMT were identical to a strain present in the donor, confirming strain transmission. Conversely, 2 patients exhibited clearance of procarcinogenic bacteria following FMT from a negative donor.CONCLUSIONBoth durable transmission and clearance of procarcinogenic bacteria occurred following FMT, suggesting that additional studies on appropriate screening measures for FMT donors and the long-term consequences and/or benefits of FMT are warranted.FUNDINGCrohn's & Colitis Foundation, the Bloomberg~Kimmel Institute for Cancer Immunotherapy at Johns Hopkins University School of Medicine, the National Cancer Institute, and the Canadian Institutes of Health Research.

Fatty Liver Disease Caused by High-Alcohol-Producing Klebsiella pneumoniae

The underlying etiology of nonalcoholic fatty liver disease (NAFLD) is believed to be quite varied. Changes in the gut microbiota have been investigated and are believed to contribute to at least some cases of the disease, though a causal relationship remains unclear. Here, we show that high-alcohol-producing Klebsiella pneumoniae (HiAlc Kpn) is associated with up to 60% of individuals with NAFLD in a Chinese cohort. Transfer of clinical isolates of HiAlc Kpn by oral gavage into mice induced NAFLD. Likewise, fecal microbiota transplant (FMT) into mice using a HiAlc-Kpn-strain-containing microbiota isolated from an individual with NASH induced NAFLD. However, selective elimination of the HiAlc Kpn strain before FMT prevented NAFLD in the recipient mice. These results suggest that at least in some cases of NAFLD an alteration in the gut microbiome drives the condition due to excess endogenous alcohol production.

Administration of Akkermansia muciniphila Ameliorates Dextran Sulfate Sodium-Induced Ulcerative Colitis in Mice

Inflammatory bowel diseases (IBDs) develop as a result of complex interactions among genes, innate immunity and environmental factors, which are related to the gut microbiota. Multiple clinical and animal data have shown that Akkermansia muciniphila is associated with a healthy mucosa. However, its precise role in colitis is currently unknown. Our study aimed to determine its protective effects and underlying mechanisms in a dextran sulfate sodium (DSS)-induced colitis mouse model. Twenty-four C57BL/6 male mice were administered A. muciniphila Muc^T or phosphate-buffered saline (PBS) once daily by oral gavage for 14 days. Colitis was induced by drinking 2% DSS from days 0 to 6, followed by 2 days of drinking normal water. Mice were weighed daily and then sacrificed on day 8. We found that A. muciniphila improved DSS-induced colitis, which was evidenced by reduced weight loss, colon length shortening and histopathology scores and enhanced barrier function. Serum and tissue levels of inflammatory cytokines and chemokines (TNF-α, IL1α, IL6, IL12A, MIP-1A, G-CSF, and KC) decreased as a result of A. muciniphila administration. Analysis of 16S rDNA sequences showed that A. muciniphila induced significant gut microbiota alterations. Furthermore, correlation analysis indicated that pro-inflammatory cytokines and other injury factors were negatively associated with Verrucomicrobia, Akkermansia, Ruminococcaceae, and Rikenellaceae, which were prominently abundant in A. muciniphila-treated mice. We confirmed that A. muciniphila treatment could ameliorate mucosal inflammation either via microbe-host interactions, which protect the gut barrier function and reduce the levels of inflammatory cytokines, or by improving the microbial community. Our findings suggest that A. muciniphila may be a potential probiotic agent for ameliorating colitis.

Role of Faecal Microbiota Transplantation for Maintenance of Remission in Patients With Ulcerative Colitis: A Pilot Study

OBJECTIVES

To study the role of faecal microbiota transplantation [FMT] in maintenance of remission in ulcerative colitis [UC].

METHODS

In this pilot study, patients with UC in clinical remission achieved after multi-session FMT were randomly allocated to either maintenance FMT or placebo colonoscopic infusion every 8 weeks, for 48 weeks. The standard of care [SOC] therapy was continued in all patients. The primary endpoint was maintenance of steroid-free clinical remission [Mayo score ≤2, all subscores ≤1] at Week 48. Secondary endpoints were achievement of endoscopic remission [endoscopic Mayo score 0] and histological remission [Nancy grade 0, 1] at Week 48.

RESULTS

In all, 61 patients in clinical remission were randomised to receive either FMT [n = 31] or placebo [n = 30]. The primary outcome was achieved in 27/31 [87.1%] patients allocated FMT versus 20/30 [66.7%] patients assigned placebo [p = 0.111]. Secondary endpoints of endoscopic remission (FMT: 18/31 [58.1%] versus placebo: 8/30 [26.7%], p = 0.026) and histological remission (FMT: 14/31 [45.2%] versus placebo: 5/30 [16.7%], p = 0. 033) were achieved in a significantly higher number of patients with FMT. Three patients receiving FMT [9.7%] and 8 patients on placebo [26.7%] relapsed. There were no serious adverse events necessitating discontinuation in patients on FMT; one patient who relapsed on placebo required colectomy.

CONCLUSIONS

Maintenance FMT in patients who are in clinical remission may help sustain clinical, endoscopic and histological remission in patients with UC.

Impact of Fecal Microbiota Transplantation on Obesity and Metabolic Syndrome-A Systematic Review

Fecal microbiota transplantation (FMT) is a gut microbial-modulation strategy that has been investigated for the treatment of a variety of human diseases, including obesity-associated metabolic disorders. This study appraises current literature and provides an overview of the effectiveness and limitations of FMT as a potential therapeutic strategy for obesity and metabolic syndrome (MS). Five electronic databases and two gray literature sources were searched up to 10 December 2018. All interventional and observational studies that contained information on the relevant population (adult patients with obesity and MS), intervention (receiving allogeneic FMT) and outcomes (metabolic parameters) were eligible. From 1096 unique citations, three randomized placebo-controlled studies (76 patients with obesity and MS, body mass index = 34.8 ± 4.1 kg/m², fasting plasma glucose = 5.8 ± 0.7 mmol/L) were included for review. Studies reported mixed results with regards to improvement in metabolic parameters. Two studies reported improved peripheral insulin sensitivity (rate of glucose disappearance, RD) at 6 weeks in patients receiving donor FMT versus patients receiving the placebo control. In addition, one study observed lower HbA1c levels in FMT patients at 6 weeks. No differences in fasting plasma glucose, hepatic insulin sensitivity, body mass index (BMI), or cholesterol markers were observed between two groups across all included studies. While promising, the influence of FMT on long-term clinical endpoints needs to be further explored. Future studies are also required to better understand the mechanisms through which changes in gut microbial ecology and engraftment of microbiota affect metabolic outcomes for patients with obesity and MS. In addition, further research is needed to better define the optimal fecal microbial preparation, dosing, and method of delivery.

Uncovering the cause of ulcerative colitis

The cause of ulcerative colitis still remains unclear. The most popular hypothesis is that colitis develops because of a complex interaction of genetic, microbial, environmental, and immunologic factors. This editorial summarizes the widely accepted hypothesis and comments on a variation of this hypothesis promoted by Dr Roediger.

The evolution of the use of faecal microbiota transplantation and emerging therapeutic indications

Developments in high-throughput microbial genomic sequencing and other systems biology techniques have given novel insight into the potential contribution of the gut microbiota to health and disease. As a result, an increasing number of diseases have been characterised by distinctive changes in the composition and functionality of the gut microbiota; however, whether such changes are cause, consequence, or incidental to the disease in question remains largely uncertain. Restoration of the gut microbiota to a premorbid state is a key novel therapeutic approach of interest, and faecal microbiota transplantation-the transfer of prescreened stool from healthy donors into the gastrointestinal tract of patients-is gaining increasing importance in both the clinical and research settings. At present, faecal microbiota transplantation is only recommended in the treatment of recurrent Clostridioides difficile infection, although a large number of trials are ongoing worldwide exploring other potential therapeutic indications.

Establishing a donor stool bank for faecal microbiota transplantation: methods and feasibility

Faecal microbiota transplantation (FMT) is a promising treatment, but donor selection and implementation in clinical practice are difficult. Here, we describe the establishment of a donor stool bank based on the Tissue Act. Stool donors were recruited among blood donors and asked to donate five times in a month. A screening questionnaire, a medical interview and testing of blood and stool were conducted before and after donations. Donations were made at home and transported to the lab, where 50 g of stool was suspended and filtered in saline and 20-mL glycerol (final concentration of 10%) to a volume of 170 mL. The processed stool was assigned a batch number, frozen within 2 h after defecation and stored at - 80 °C for up to 1 year. All steps were documented and cross-checked before donor stool were released for clinical use. Thirteen donors were eligible at the first interview and started donations. Two donors were excluded due to a positive Helicobacter pylori test, two withdrew consent and one was lost to follow-up. One donor took a single dose of NSAIDs 2 days prior to a donation, which was discarded. There were no other excluding findings at the second interview or testing. Eight of the 13 donors were approved as stool donors. All donated five times with each donation yielding 1-6 portions. Eighty-four portions were released for clinical use. Recruiting stool donors among blood donors is safe and effective. The Tissue Act yields an appropriate regulative framework for FMT.

The Gut Microbiome in Inflammatory Bowel Disease: Lessons Learned From Other Immune-Mediated Inflammatory Diseases

There is a growing appreciation for the role of the gut microbiome in human health and disease. Aided by advances in sequencing technologies and analytical methods, recent research has shown the healthy gut microbiome to possess considerable diversity and functional capacity. Dysbiosis of the gut microbiota is believed to be involved in the pathogenesis of not only diseases that primarily affect the gastrointestinal tract but also other less obvious diseases, including neurologic, rheumatologic, metabolic, hepatic, and other illnesses. Chronic immune-mediated inflammatory diseases (IMIDs) represent a group of diseases that share many underlying etiological factors including genetics, aberrant immunological responses, and environmental factors. Gut dysbiosis has been reported to be common to IMIDs as a whole, and much effort is currently being directed toward elucidating microbiome-mediated disease mechanisms and their implications for causality. In this review, we discuss gut microbiome studies in several IMIDs and show how these studies can inform our understanding of the role of the gut microbiome in inflammatory bowel disease.

Long-Term Safety and Efficacy of Fecal Microbiota Transplant in Active Ulcerative Colitis

INTRODUCTION AND OBJECTIVE

The therapeutic role of fecal microbiota transplantation in ulcerative colitis varies across different reports. This study aims to evaluate the long-term safety and efficacy of a strategy called step-up fecal microbiota transplantation for ulcerative colitis.

METHODS

Two clinical trials (NCT01790061, NCT02560727) for moderate-to-severe ulcerative colitis (Mayo score range 6-12) were performed from November 2012 to July 2017. Both studies were pooled for analysis on the safety and efficacy of fecal microbiota transplantation in patients with ulcerative colitis over a 1-year follow-up. The step-up fecal microbiota transplantation strategy included step 1: single fecal microbiota transplantation; step 2: two or more fecal microbiota transplantations; and step 3: fecal microbiota transplantations followed by immunosuppressants. Long-term clinical efficacy and adverse events were assessed, and multiple factors related to fecal microbiota transplantation were evaluated.

RESULTS

Of 134 eligible patients in this real-word study, 81.3% (109/134) were included for analysis. The follow-up ranged from 1 to 5 years. Fecal microbiota transplantation-related adverse events were observed in 17.4% (43/247) of fecal microbiota transplantation procedures including one serious adverse event (myasthenia gravis) and 56 non-serious adverse events. Multivariable logistic regression analysis showed that both the method of preparation of microbiota from stool using the automatic system and the delivery method of colonic transendoscopic enteral tubing were associated with a lower rate of fecal microbiota transplantation-related adverse events (p = 0.023, p = 0.017, respectively). In total, 74.3% (81/109) and 51.4% (56/109) of patients achieved clinical response at 1 month and 3 months after step-up fecal microbiota transplantation, respectively.

CONCLUSIONS

Fecal microbiota transplantation should be a safe and promising therapy for ulcerative colitis. The improved fecal microbiota preparation and colonic transendoscopic enteral tubing might reduce the rate of adverse events in ulcerative colitis.

TRIAL REGISTRATION

ClinicalTrials.gov NCT01790061, NCT02560727.

Parkinson's Disease: The Emerging Role of Gut Dysbiosis, Antibiotics, Probiotics, and Fecal Microbiota Transplantation

The role of the microbiome in health and human disease has emerged at the forefront of medicine in the 21st century. Over the last 2 decades evidence has emerged to suggest that inflammation-derived oxidative damage and cytokine induced toxicity may play a significant role in the neuronal damage associated with Parkinson’s disease (PD). Presence of pro-inflammatory cytokines and T cell infiltration has been observed in the brain parenchyma of patients with PD. Furthermore, evidence for inflammatory changes has been reported in the enteric nervous system, the vagus nerve branches and glial cells. The presence of α-synuclein deposits in the post-mortem brain biopsy in patients with PD has further substantiated the role of inflammation in PD. It has been suggested that the α-synuclein misfolding might begin in the gut and spread “prion like” via the vagus nerve into lower brainstem and ultimately to the midbrain; this is known as the Braak hypothesis. It is noteworthy that the presence of gastrointestinal symptoms (constipation, dysphagia, and hypersalivation), altered gut microbiota and leaky gut have been observed in PD patients several years prior to the clinical onset of the disease. These clinical observations have been supported by in vitro studies in mice as well, demonstrating the role of genetic (α-synuclein overexpression) and environmental (gut dysbiosis) factors in the pathogenesis of PD. The restoration of the gut microbiome in patients with PD may alter the clinical progression of PD and this alteration can be accomplished by carefully designed studies using customized probiotics and fecal microbiota transplantation.

Manipulation of the Gut-Liver Axis Using Microbiome Restoration Therapy in Primary Sclerosing Cholangitis

Alteration of the normal gut-liver axis is important in primary sclerosing cholangitis (PSC). Lack of effective medical therapy for PSC makes microbiome restoration an alluring therapeutic target. Allegretti et al. performed an open-label safety trial of fecal microbiota transplant (FMT) in noncirrhotic PSC patients with inflammatory bowel disease in remission on minimal therapy. FMT was safe in this population, and after FMT, there was a stable, early increase in microbial diversity and donor engraftment with mixed effects on alkaline phosphatase but no significant change in fecal bile acid profile. Further trials are needed to find whether FMT has a role to play in PSC therapy.

Fecal Microbial Transplantation and Its Potential Application in Cardiometabolic Syndrome

Newly revealed links between inflammation, obesity, and cardiometabolic syndrome have created opportunities to try previously unexplored therapeutic modalities in these common and life-risking disorders. One potential modulator of these complex disorders is the gut microbiome, which was described in recent years to be altered in patients suffering from features of cardiometabolic syndrome and to transmit cardiometabolic phenotypes upon transfer into germ-free mice. As a result, there is great interest in developing new modalities targeting the altered commensal bacteria as a means of treatment for cardiometabolic syndrome. Fecal microbiota transplantation (FMT) is one such modality in which a disease-associated microbiome is replaced by a healthy microbiome configuration. So far clinical use of FMT has been overwhelmingly successful in recurrent Clostridium difficile infection and is being extensively studied in other microbiome-associated pathologies such as cardiometabolic syndrome. This review will focus on the rationale, promises and challenges in FMT utilization in human disease. In particular, it will overview the role of the gut microbiota in cardiometabolic syndrome and the rationale, experience, and prospects of utilizing FMT treatment as a potential preventive and curative treatment of metabolic human disease.

Capturing the Biologic Onset of Inflammatory Bowel Diseases: Impact on Translational and Clinical Science

While much progress has been made in the last two decades in the treatment and the management of inflammatory bowel diseases (IBD)-both ulcerative colitis (UC) and Crohn's Disease (CD)-as of today these conditions are still diagnosed only after they have become symptomatic. This is a major drawback since by then the inflammatory process has often already caused considerable damage and the disease might have become partially or totally unresponsive to medical therapy. Late diagnosis in IBD is due to the lack of accurate, non-invasive indicators that would allow disease identification during the pre-clinical stage-as it is often done in many other medical conditions. Here, we will discuss what is known about the biologic onset and pre-clinical CD with an emphasis on studies conducted in patients' first degree relatives. We will then review the possible strategies to diagnose IBD very early in time including screening, available disease markers and imaging, and the possible clinical implications of treating these conditions at or close to their biologic onset. Later, we will review the potential impact of conducting translational research in IBD during the pre-clinical stage, especially focusing on the role of the microbiome in disease etiology and pathogenesis. Finally, we will highlight possible future developments in the field and how they can impact IBD management and our scientific knowledge of these conditions.

Fecal microbiota transplantation: great potential with many challenges

In January of 2019, Samuel P. Costello and colleagues published a wonderfully executed, double blind placebo-controlled trial on fecal microbiota transplantation (FMT) versus autologous stool as placebo in mild to moderately active adult ulcerative colitis [UC: one type of inflammatory bowel disease (IBD)] patients. This review-commentary examines the current state of knowledge on human gut microbiome (live microbiota + their products and surrounding environment, i.e., fecal matter) and microbial therapeutics from a gastrointestinal (GI) clinician's standpoint. The varied forms of dysbiosis as the target of FMT, recipient donor and placebo considerations are also discussed in respect to randomized control trials in IBD [and the lack thereof in Crohn's disease (CD)] with this unconventional treatment modality.

Why targeting the microbiome is not so successful: can randomness overcome the adaptation that occurs following gut manipulation?

The microbiome is explored as a potential target for therapy of bowel and systemic diseases. Fecal microbiota transplantation (FMT) has demonstrated efficacy in Clostridium difficile infection. However, clinical results regarding other diseases are modest, despite the abundant research on the microbiome over the last decade. Both high rate variability of the microbiome and adaptation to gut manipulations may underlie the lack of ultimate effects of FMT, probiotics, prebiotics, synbiotics, and antibiotics, which are aimed at restoring a healthier microbiome. The present review discusses the inherent variability of the microbiome and multiple factors that affect its diversity, as possible causes of the adaptation of the gut microbiome to chronic manipulation. The potential use of randomness is proposed, as a means of overcoming the adaptation and of restoring some of the inherent variability, with the goal of improving the long-term efficacy of these therapies.

Evolution of fecal microbiota transplantation in methodology and ethical issues

Fecal microbiota transplantation (FMT), the core therapy for remodeling the gut microbiota with a long medical history, has gained great attention worldwide in recent years. Increasing studies have explored its indications, methodology, efficacy, safety, and ethics. Purified forms of FMT, using an automated method for the purification of fecal microbiota from stool, has become a reality. Colonic transendoscopic enteral tubing makes frequent FMT delivery into the whole colon feasible. This review focuses on the recent progress in laboratory preparation, updated clinical strategies, novel delivery methods, and ethical issues surrounding FMT in clinical studies.