Fecal Microbiota Transplantation is a Promising Switch Therapy for Patients with Prior Failure of Infliximab in Crohn's Disease

Gut microbiota in Crohn's disease pathogenesis

Inflammatory bowel diseases (IBDs) are classified into two distinct types based on the area and severity of inflammation: Crohn's disease (CD) and ulcerative colitis. In CD, gut bacteria can infiltrate mesenteric fat, causing expansion known as creeping fat, which may limit bacterial spread and inflammation but can promote fibrosis. The gut bacteria composition varies depending on whether the colon or ileum is affected. Fecal microbiota transplantation (FMT) transfers feces from a healthy donor to restore gut microbiota balance, often used in IBD patients to reduce inflammation and promote mucosal repair. The use of FMT for CD remains uncertain, with insufficient evidence to fully endorse it as a definitive treatment. While some studies suggest it may improve symptoms, questions about the duration of these improvements and the need for repeated treatments persist. There is a pressing need for methods that provide long-term benefits, as highlighted by Wu et al's research.

The Gut Microbiota Affects Anti-TNF Responsiveness by Activating the NAD+ Salvage Pathway in Ulcerative Colitis

Approximately 50% of the patients with ulcerative colitis (UC) are primarily nonresponsive to anti-tumor necrosis factor (TNF) therapy or lose their responsiveness over time. The gut microbiota plays an important role in the resistance of UC to anti-TNF therapy; however, the underlying mechanism remains unknown. Here, it is found that the transplantation of gut fecal microbiota from patients with UC alters the diversity of the gut microbiota in dextran sulfate sodium-induced colitis mice and may affect the therapeutic responsiveness of mice to infliximab. Furthermore, the abundances of Romboutsia and Fusobacterium increase in the tissues of patients with UC who do not respond to anti-TNF therapy. Differentially abundant metabolites are mainly enriched in nicotinate and nicotinamide metabolism in NCM460 cells after Fusobacterium nucleatum infection. Mechanistically, F. nucleatum promotes the nicotinamide adenine dinucleotide (NAD+) salvage pathway by upregulating NAMPT expression, which subsequently leads to the activation of the p38 mitogen-activated protein kinase (MAPK) signaling pathway and promotes the secretion of inflammatory factors, ultimately inhibiting the therapeutic response to anti-TNF drugs. These findings demonstrate that the gut microbiota can influence the response to anti-TNF therapy in patients with UC and highlight the therapeutic potential of targeting F. nucleatum and its associated pathways for preventing and treating drug resistance in UC.

Factors of faecal microbiota transplantation applied to cancer management

The homeostasis of the microbiota is essential for human health. In particular, the gut microbiota plays a critical role in the regulation of the immune system. Thus, faecal microbiota transplantation (FMT), a technology that has rapidly developed in the last decade, has specifically been utilised for the treatment of intestinal inflammation and has recently been found to be able to treat tumours in combination with immunotherapy. FMT has become a breakthrough in enhancing the response rate to immunotherapy in cancer patients by altering the composition of the patient's gut microbiota. This review discusses the mechanisms of faecal microorganism effects on tumour development, drug treatment efficacy, and adverse effects and describes the recent clinical research trials on FMT. Moreover, the factors influencing the efficacy and safety of FMT are described. We summarise the possibilities of faecal transplantation in the treatment of tumours and its complications and propose directions to explore the development of FMT.

Comparison between washed microbiota transplantation and infliximab: Medical cost during long-term management in patients with inflammatory bowel disease

BACKGROUND

Both infliximab (IFX) and fecal microbiota transplantation (FMT) have shown the efficacy for inflammatory bowel disease (IBD). However, there has no head-to-head study on the cost-value of the such treatments on IBD. This study aimed to compare the medical costs using IFX and the new method of FMT (washed microbiota transplantation [WMT]) in the long-term management for IBD under the current health economic condition in China.

METHODS

Patients with IBD who underwent initial WMT via upper gastrointestinal endoscopy, mid-gut tube, or colonic transendoscopic enteral tubing at a university hospital between April 2013 and August 2021 and achieved the long-term sustainment with WMT or WMT combined with mesalazine until August 2022 were recruited in the real-world. The costs and hospitalizations were analyzed among two therapies mentioned above and IFX standard therapy. The charge of WMT was stable in the long term at our center, and the charge of IFX came from virtual statistics publicized by China Healthcare Security.

RESULTS

Sixty eligible patients with IBD were included in the study. The long-term costs of patients using WMT monotherapy annually or per hospitalization were lower than those on WMT combined with mesalazine, respectively ( p < 0.001, respectively). The cumulative costs of IFX at the time of 0.52 and 0.85 years exceeded that of the above WMT, respectively ( p < 0.001, respectively). Besides, patients on WMT monotherapy paid 51.1 k CNY annually in the nonsustain phase but cut down the costs by 7.2 k CNY and duration of hospitalization by 5.1 days per hospitalization when reaching the goal of sustainment.

CONCLUSION

This study demonstrated that WMT could dramatically reduce the cost and duration of hospitalizations in the long-term sustainment in the current Chinese IBD cohort. Compared with IFX, WMT could be a good way for the patients with IBD achieving long-term sustainment and saving medical costs.

Pathogens in Crohn's Disease: The Role of Adherent Invasive Escherichia coli

In Crohn's disease (CD), gut dysbiosis is marked by the prevalence of pathogenic bacterial species. Although several microbes have been reported as risk factors or causative agents of CD, it is not yet clear which is the real trigger of the disease. Thirty years ago, a new pathovar of Escherichia coli strain was isolated in the ileal mucosa of CD patients. This strain, called adherent invasive E. coli (AIEC), for its ability to invade the intestinal mucosa, could represent the causative agent of the disease. Several authors studied the mechanisms by which the AIEC penetrate and replicate within macrophages, and release inflammatory cytokines sustaining inflammation. In this review we will discuss about the role of AIEC in the pathogenesis of CD, the virulence factors mediating adhesion and invasion of AIEC in mucosal tissue, the environmental conditions improving AIEC survival and replication within macrophages. Finally, we will also give an overview of the new strategies developed to limit AIEC overgrowth.

Fecal microbiota transplantation for induction of remission in Crohn's disease: a systematic review and meta-analysis

PURPOSE

Fecal microbiota transplantation (FMT) has been found to be a potential treatment for Crohn's disease (CD). We sought to perform a systematic review and meta-analysis to evaluate the efficacy and safety of FMT in CD.

METHODS

Electronic databases were searched for studies until January 2023. Clinical remission was established as the primary outcome. The secondary outcome was clinical response, endoscopic remission, minor adverse events, serious adverse events, and changes in disease activity indices, biochemical indicators, and microbial diversities. Pooled effect sizes and 95% confidence intervals (CIs) were calculated under the random effects model.

RESULTS

Eleven cohort studies and one randomized controlled trial involving 228 patients were included. In a meta-analysis, the pooled proportion of adult patients with active CD that achieved clinical remission 2 to 4 weeks after FMT was 57% (95% CI = 49-64%) with a low risk of heterogeneity (I² = 37%). Furthermore, our results showed that FMT significantly (standardized mean difference = -0.66; 95% CI = -1.12 to -0.20; I² = 0) reduced Crohn's disease activity index scores 4 to 8 weeks after FMT. Subgroup analyses showed no difference between FMT methodologies, except for pre-FMT treatment with antibiotics (P = 0.02). Most adverse events were self-limiting and disappeared spontaneously within hours or days after FMT. Microbiota analysis showed an increased Shannon diversity and a shift toward donor-like microbiome after FMT.

CONCLUSION

FMT could be a promising therapy in the short-term treatment of active CD. More placebo-controlled randomized trials with a long-term follow-up treatment are necessary.

TRIAL REGISTRATION

https://www.crd.york.ac.uk/prospero/display_record.php?ID=CRD42022322694 No. CRD42022322694.

Crosstalk between Gut Microbiota and Host Immunity: Impact on Inflammation and Immunotherapy

Gut microbes and their metabolites are actively involved in the development and regulation of host immunity, which can influence disease susceptibility. Herein, we review the most recent research advancements in the gut microbiota-immune axis. We discuss in detail how the gut microbiota is a tipping point for neonatal immune development as indicated by newly uncovered phenomenon, such as maternal imprinting, in utero intestinal metabolome, and weaning reaction. We describe how the gut microbiota shapes both innate and adaptive immunity with emphasis on the metabolites short-chain fatty acids and secondary bile acids. We also comprehensively delineate how disruption in the microbiota-immune axis results in immune-mediated diseases, such as gastrointestinal infections, inflammatory bowel diseases, cardiometabolic disorders (e.g., cardiovascular diseases, diabetes, and hypertension), autoimmunity (e.g., rheumatoid arthritis), hypersensitivity (e.g., asthma and allergies), psychological disorders (e.g., anxiety), and cancer (e.g., colorectal and hepatic). We further encompass the role of fecal microbiota transplantation, probiotics, prebiotics, and dietary polyphenols in reshaping the gut microbiota and their therapeutic potential. Continuing, we examine how the gut microbiota modulates immune therapies, including immune checkpoint inhibitors, JAK inhibitors, and anti-TNF therapies. We lastly mention the current challenges in metagenomics, germ-free models, and microbiota recapitulation to a achieve fundamental understanding for how gut microbiota regulates immunity. Altogether, this review proposes improving immunotherapy efficacy from the perspective of microbiome-targeted interventions.

Colonic Transendoscopic Enteral Tubing Is a New Pathway to Microbial Therapy, Colonic Drainage, and Host-Microbiota Interaction Research

The limitation of traditional delivery methods for fecal microbiota transplantation (FMT) gave birth to colonic transendoscopic enteral tubing (TET) to address the requirement of frequent FMTs. Colonic TET as a novel endoscopic intervention has received increasing attention in practice since 2015 in China. Emerging studies from multiple centers indicate that colonic TET is a promising, safe, and practical delivery method for microbial therapy and administering medication with high patient satisfaction. Intriguingly, colonic TET has been used to rescue endoscopy-related perforations by draining colonic air and fluid through the TET tube. Recent research based on collecting ileocecal samples through a TET tube has contributed to demonstrating community dynamics in the intestine, and it is expected to be a novel delivery of proof-of-concept in host-microbiota interactions and pharmacological research. The present article aims to review the concept and techniques of TET and to explore microbial therapy, colonic drainage, and microbial research based on colonic TET.

Unveiling and harnessing the human gut microbiome in the rising burden of non-communicable diseases during urbanization

The world is witnessing a global increase in the urban population, particularly in developing Asian and African countries. Concomitantly, the global burden of non-communicable diseases (NCDs) is rising, markedly associated with the changing landscape of lifestyle and environment during urbanization. Accumulating studies have revealed the role of the gut microbiome in regulating the immune and metabolic homeostasis of the host, which potentially bridges external factors to the host (patho-)physiology. In this review, we discuss the rising incidences of NCDs during urbanization and their links to the compositional and functional dysbiosis of the gut microbiome. In particular, we elucidate the effects of urbanization-associated factors (hygiene/pollution, urbanized diet, lifestyles, the use of antibiotics, and early life exposure) on the gut microbiome underlying the pathogenesis of NCDs. We also discuss the potential and feasibility of microbiome-inspired and microbiome-targeted approaches as novel avenues to counteract NCDs, including fecal microbiota transplantation, diet modulation, probiotics, postbiotics, synbiotics, celobiotics, and precision antibiotics.

Alterations and Potential Applications of Gut Microbiota in Biological Therapy for Inflammatory Bowel Diseases

Inflammatory bowel disease (IBD), including Crohn’s disease and ulcerative colitis, is a chronic immune-mediated inflammatory disorder of the gastrointestinal tract that is closely associated with dysbiosis of the intestinal microbiota. Currently, biologic agents are the mainstream therapies for IBD. With the increasing incidence of IBD, limitations of biologic agents have gradually emerged during treatment. Recent studies have indicated that gut microbiota is highly correlated with the efficacy of biologic agents. This review focuses on alterations in both the components and metabolites of gut microbiota during biological therapy for IBD, systematically summarises the specific gut microbiota closely related to the clinical efficacy, and compares current predictive models for the efficacy of biologics, further highlighting the predictive value of intestinal microbiota. Based on the mechanistic analysis of faecal microbiota transplantation (FMT) and biologic agents, a new therapeutic strategy, comprising a combination of FMT and biologics, has been proposed as a promising treatment for IBD with improved efficacy.