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1.
Dig Dis Sci ; 69(7): 2289-2303, 2024 Jul.
Article in English | MEDLINE | ID: mdl-38896362

ABSTRACT

Mycobacterium avium ssp. paratuberculosis (MAP) has been implicated in the development of Crohn's disease (CD) for over a century. Similarities have been noted between the (histo)pathological presentation of MAP in ruminants, termed Johne's disease (JD), and appearances in humans with CD. Analyses of disease presentation and pathology suggest a multi-step process occurs that consists of MAP infection, dysbiosis of the gut microbiome, and dietary influences. Each step has a role in the disease development and requires a better understanding to implementing combination therapies, such as antibiotics, vaccination, faecal microbiota transplants (FMT) and dietary plans. To optimise responses, each must be tailored directly to the activity of MAP, otherwise therapies are open to interpretation without microbiological evidence that the organism is present and has been influenced. Microscopy and histopathology enables studies of the mycobacterium in situ and how the associated disease processes manifest in the patient e.g., granulomas, fissuring, etc. The challenge for researchers has been to prove the relationship between MAP and CD with available laboratory tests and methodologies, such as polymerase chain reaction (PCR), MAP-associated DNA sequences and bacteriological culture investigations. These have, so far, been inconclusive in revealing the relationship of MAP in patients with CD. Improved and accurate methods of detection will add to evidence for an infectious aetiology of CD. Specifically, if the bacterial pathogen can be isolated, identified and cultivated, then causal relationships to disease can be confirmed, especially if it is present in human gut tissue. This review discusses how MAP may cause the inflammation seen in CD by relating its known pathogenesis in cattle, and from examples of other mycobacterial infections in humans, and how this would impact upon the difficulties with diagnostic tests for the organism.


Subject(s)
Crohn Disease , Mycobacterium avium subsp. paratuberculosis , Paratuberculosis , Crohn Disease/microbiology , Humans , Mycobacterium avium subsp. paratuberculosis/isolation & purification , Mycobacterium avium subsp. paratuberculosis/pathogenicity , Paratuberculosis/microbiology , Paratuberculosis/diagnosis , Animals , Gastrointestinal Microbiome/physiology
2.
Proc Natl Acad Sci U S A ; 117(35): 21536-21545, 2020 09 01.
Article in English | MEDLINE | ID: mdl-32817490

ABSTRACT

The building evidence for the contribution of microbiota to human disease has spurred an effort to develop therapies that target the gut microbiota. This is particularly evident in inflammatory bowel diseases (IBDs), where clinical trials of fecal microbiota transplantation have shown some efficacy. To aid the development of novel microbiota-targeted therapies and to better understand the biology underpinning such treatments, we have used gnotobiotic mice to model microbiota manipulations in the context of microbiotas from humans with inflammatory bowel disease. Mice colonized with IBD donor-derived microbiotas exhibit a stereotypical set of phenotypes, characterized by abundant mucosal Th17 cells, a deficit in the tolerogenic RORγt+ regulatory T (Treg) cell subset, and susceptibility to disease in colitis models. Transplanting healthy donor-derived microbiotas into mice colonized with human IBD microbiotas led to induction of RORγt+ Treg cells, which was associated with an increase in the density of the microbiotas following transplant. Microbiota transplant reduced gut Th17 cells in mice colonized with a microbiota from a donor with Crohn's disease. By culturing strains from this microbiota and screening them in vivo, we identified a specific strain that potently induces Th17 cells. Microbiota transplants reduced the relative abundance of this strain in the gut microbiota, which was correlated with a reduction in Th17 cells and protection from colitis.


Subject(s)
Fecal Microbiota Transplantation , Inflammatory Bowel Diseases/microbiology , Nuclear Receptor Subfamily 1, Group F, Member 3/immunology , T-Lymphocytes, Regulatory/immunology , Th17 Cells/immunology , Animals , Colitis/prevention & control , Colon/microbiology , Crohn Disease/metabolism , Crohn Disease/microbiology , Cytokines/immunology , Disease Models, Animal , Feces/microbiology , Female , Gastrointestinal Microbiome/immunology , Humans , Inflammatory Bowel Diseases/immunology , Male , Mice , Mice, Inbred C57BL , T-Lymphocytes, Regulatory/microbiology , Th17 Cells/microbiology
3.
Gut ; 2022 Jul 25.
Article in English | MEDLINE | ID: mdl-35879048

ABSTRACT

OBJECTIVE: Faecal microbiota transplantation (FMT) has variable efficacy in treating UC. Recently, oral lyophilised FMT was found to induce remission in patients with UC, with one donor having 100% efficacy compared with a second donor (36% efficacy). We characterised differences in the gut microbiota of these two donors with the aim of improving FMT donor selection. DESIGN: Faecal samples from the two donors were collected over a period of 44 (donor 1) or 70 (donor 2) weeks. The microbiome and metabolome were profiled using shotgun metagenomics and untargeted metabolomics RESULTS: Gut microbiome long-term stability was highly evident in the effective donor. Donor microbiota species evenness was a robust feature associated with clinical efficacy across two clinical trials of FMT in UC, leading to increased donor species engraftment in patients. Alpha diversity and beta diversity of donor gut microbiotas significantly differed. 90 bacterial species and one archaeon were differentially abundant between donors, 44 of which were >0.1% in relative abundance. 17/44 species were enriched in the effective donor, 11 of which (64.7%) were assembled into high-quality genomes that were prevalent (≥75% samples) in that donor, and six showed evidence of engraftment in patients. Taxonomic differences between donors translated to substantial microbial functional differences that were validated using metabolomics. CONCLUSION: Donor microbiota stability and species evenness were identified as novel metrics that were associated with therapeutic efficacy in UC, beyond individual microbial species or metabolites. These metrics may represent community resilience that translates to better engraftment in the host. TRIAL REGISTRATION NUMBER: ACTRN12619000611123.

4.
Helicobacter ; 26(5): e12830, 2021 Oct.
Article in English | MEDLINE | ID: mdl-34247436

ABSTRACT

BACKGROUND: Vonoprazan fumarate is a novel potassium-competitive acid blocker more effective in suppressing acid production than proton pump inhibitors (PPIs) and when combined with antibiotics has been used to eradicate Helicobacter pylori (H. pylori) infection. However, it has not yet been examined in an Australian setting. This study aimed to report on the efficacy and safety of vonoprazan-containing antibiotic combination therapies in the eradication of H. pylori. METHODS: A single-center, exploratory, clinical review of patients 18 years or over, positive for H. pylori on Urea Breath Test (UBT), and/or histopathology who underwent a 10-day treatment of combination antibiotics plus vonoprazan between January 2017 and September 2019 was conducted. Eleven different combinations of antibiotics that included 2-5 different antibiotics predominantly amoxicillin, rifabutin, levofloxacin, furazolidone, nitazoxanide, and tetracycline were included. The eradication success was based on negative UBT results and/or histopathology results after the treatment. Descriptive statistics were summarized. RESULTS: One hundred and fifty-three patients (Female n = 74, 48%) with a positive for H. pylori were treated with vonoprazan-containing antibiotic combination therapy during the study period. Of the 153 patients, 48 (31%) had previously failed a PPI-based H. pylori treatment. Follow-up was available for 66/153 (43%) patients. In those who completed follow-up, overall eradication was achieved in 97% (64/66) of patients. In the subgroup of patients treated for the first time, eradication was achieved in 100% (44/44). In those who had failed prior, non-vonoprazan-containing treatment, eradication was achieved in 91% (20/22) of patients. CONCLUSIONS: Vonoprazan-containing antibiotic therapy is an effective H. pylori eradication treatment. It is capable of achieving 100% efficacy in patients treated for the first time and even 91% efficacy in patients with previous eradication failure. Subsequent studies utilizing a factorial design will be needed to optimize each regimen as most regimens contained more than two antibiotics.


Subject(s)
Helicobacter Infections , Helicobacter pylori , Adolescent , Adult , Amoxicillin/therapeutic use , Anti-Bacterial Agents/therapeutic use , Australia , Clarithromycin/therapeutic use , Drug Therapy, Combination , Female , Helicobacter Infections/drug therapy , Humans , Male , Proton Pump Inhibitors/therapeutic use , Pyrroles , Sulfonamides , Treatment Outcome
5.
Med J Aust ; 214(8): 365-370, 2021 05.
Article in English | MEDLINE | ID: mdl-33502004

ABSTRACT

OBJECTIVES: To determine the age-standardised prevalence of inflammatory bowel disease (IBD) in a metropolitan area of Sydney, with a focus on its prevalence among older people. DESIGN, SETTING: Population-based epidemiological study of people with IBD in the City of Canada Bay, a local government area in the inner west of Sydney, during 1 March 2016 - 10 November 2016. PARTICIPANTS: Patients diagnosed with confirmed IBD according to the Copenhagen or revised Porto criteria. MAIN OUTCOME MEASURES: Crude prevalence of IBD, including Crohn disease and ulcerative colitis; age-standardised prevalence of IBD, based on the World Health Organization standard population; prevalence rates among people aged 65 years or more. RESULTS: The median age of 364 people with IBD was 47 years (IQR, 34-62 years); 185 were women (50.8%). The crude IBD prevalence rate was 414 cases (95% CI, 371-456 cases) per 100 000 population; the age-standardised rate was 348 cases (95% CI, 312-385 cases) per 100 000 population. The age-standardised rate for Crohn disease was 166 cases (95% CI, 141-192 cases) per 100 000 population; for ulcerative colitis, 148 cases (95% CI, 124-171 cases) per 100 000 population. The IBD prevalence rate in people aged 65 years or more was 612 cases (95% CI, 564-660 cases) per 100 000, and for those aged 85 years or more, 891 cases (95% CI, 833-949 cases) per 100 000; for people under 65, the rate was 380 cases (95% CI, 342-418 cases) per 100 000. CONCLUSIONS: We found that the prevalence of confirmed IBD in a metropolitan sample was highest among older people. Challenges for managing older patients with IBD include higher rates of comorbid conditions, polypharmacy, and cognitive decline, and the immunosuppressive nature of standard therapies for IBD.


Subject(s)
Colitis, Ulcerative/epidemiology , Crohn Disease/epidemiology , Adolescent , Adult , Age Distribution , Age Factors , Aged , Aged, 80 and over , Australia/epidemiology , Child , Cities/epidemiology , Colitis, Ulcerative/diagnosis , Crohn Disease/diagnosis , Female , Humans , Male , Middle Aged , Prevalence , Retrospective Studies , Young Adult
6.
Dig Dis Sci ; 66(2): 348-358, 2021 02.
Article in English | MEDLINE | ID: mdl-33089484

ABSTRACT

For decades, Mycobacterium avium subspecies paratuberculosis (MAP) has been linked to the pathogenesis of Crohn's disease. Despite many investigations and research efforts, there remains no clear unifying explanation of its pathogenicity to humans. Proponents argue Crohn's disease shares many identical features with a granulomatous infection in ruminants termed Johne's disease and similarities with ileo-cecal tuberculosis. Both are caused by species within the Mycobacterium genus. Sceptics assert that since MAP is found in individuals diagnosed with Crohn's disease as well as in healthy population controls, any association with CD is coincidental. This view is supported by the uncertain response of patients to antimicrobial therapy. This report aims to address the controversial aspects of this proposition with information and knowledge gathered from several disciplines, including microbiology and veterinary medicine. The authors hope that this discussion will stimulate further research aimed at confirming or refuting the contribution of MAP to the pathogenesis of Crohn's disease and ultimately lead to advanced targeted clinical therapies.


Subject(s)
Crohn Disease/microbiology , Crohn Disease/physiopathology , Mycobacterium avium subsp. paratuberculosis/isolation & purification , Paratuberculosis/microbiology , Paratuberculosis/physiopathology , Animals , Clinical Trials as Topic/methods , Crohn Disease/genetics , Humans , Mycobacterium avium subsp. paratuberculosis/genetics , Paratuberculosis/genetics , Polymerase Chain Reaction/methods
7.
Gut ; 69(5): 801-810, 2020 05.
Article in English | MEDLINE | ID: mdl-32047093

ABSTRACT

OBJECTIVE: Faecal microbiota transplantation (FMT) has proved to be an extremely effective treatment for recurrent Clostridioides difficile infection, and there is interest in its potential application in other gastrointestinal and systemic diseases. However, the recent death and episode of septicaemia following FMT highlights the need for further appraisal and guidelines on donor evaluation, production standards, treatment facilities and acceptable clinical indications. DESIGN: For these consensus statements, a 24-member multidisciplinary working group voted online and then convened in-person, using a modified Delphi approach to formulate and refine a series of recommendations based on best evidence and expert opinion. Invitations to participate were directed to Australian experts, with an international delegate assisting the development. The following issues regarding the use of FMT in clinical practice were addressed: donor selection and screening, clinical indications, requirements of FMT centres and future directions. Evidence was rated using the GRADE (Grading of Recommendations Assessment, Development and Evaluation) system. RESULTS: Consensus was reached on 27 statements to provide guidance on best practice in FMT. These include: (1) minimum standards for donor screening with recommended clinical selection criteria, blood and stool testing; (2) accepted routes of administration; (3) clinical indications; (4) minimum standards for FMT production and requirements for treatment facilities acknowledging distinction between single-site centres (eg, hospital-based) and stool banks; and (5) recommendations on future research and product development. CONCLUSIONS: These FMT consensus statements provide comprehensive recommendations around the production and use of FMT in clinical practice with relevance to clinicians, researchers and policy makers.


Subject(s)
Clostridium Infections/therapy , Fecal Microbiota Transplantation/methods , Practice Guidelines as Topic , Australia , Consensus , Donor Selection , Female , Health Facilities/statistics & numerical data , Humans , Male , Treatment Outcome
8.
Gastroenterology ; 156(5): 1440-1454.e2, 2019 Apr.
Article in English | MEDLINE | ID: mdl-30529583

ABSTRACT

BACKGROUND & AIMS: Fecal microbiota transplantation (FMT) can induce remission in patients with ulcerative colitis (UC). In a randomized controlled trial of FMT in patients with active UC, we aimed to identify bacterial taxonomic and functional factors associated with response to therapy. METHODS: We performed a double-blind trial of 81 patients with active UC randomly assigned to groups that received an initial colonoscopic infusion and then intensive multidonor FMT or placebo enemas, 5 d/wk for 8 weeks. Patients in the FMT group received blended homogenized stool from 3-7 unrelated donors. Patients in the placebo group were eligible to receive open-label FMT after the double-blind study period. We collected 314 fecal samples from the patients at screening, every 4 weeks during treatment, and 8 weeks after the blinded or open-label FMT therapy. We also collected 160 large-bowel biopsy samples from the patients at study entry, at completion of 8 weeks of blinded therapy, and at the end of open-label FMT, if applicable. We analyzed 105 fecal samples from the 14 individual donors (n = 55), who in turn contributed to 21 multidonor batches (n = 50). Bacteria in colonic and fecal samples were analyzed by both 16S ribosomal RNA gene and transcript amplicon sequencing; 285 fecal samples were analyzed by shotgun metagenomics, and 60 fecal samples were analyzed for metabolome features. RESULTS: FMT increased microbial diversity and altered composition, based on analyses of colon and fecal samples collected before vs after FMT. Diversity was greater in fecal and colon samples collected before and after FMT treatment from patients who achieved remission compared with patients who did not. Patients in remission after FMT had enrichment of Eubacterium hallii and Roseburia inulivorans compared with patients who did not achieve remission after FMT and had increased levels of short-chain fatty acid biosynthesis and secondary bile acids. Patients who did not achieve remission had enrichment of Fusobacterium gonidiaformans, Sutterella wadsworthensis, and Escherichia species and increased levels of heme and lipopolysaccharide biosynthesis. Bacteroides in donor stool were associated with remission in patients receiving FMT, and Streptococcus species in donor stool was associated with no response to FMT. CONCLUSIONS: In an analysis of fecal and colonic mucosa samples from patients receiving FMT for active UC and stool samples from donors, we associated specific bacteria and metabolic pathways with induction of remission. These findings may be of value in the design of microbe-based therapies for UC. ClinicalTrials.gov, Number NCT01896635.


Subject(s)
Bacteria/metabolism , Colitis, Ulcerative/therapy , Gastrointestinal Microbiome , Bacteria/classification , Bacteria/genetics , Bacteria/growth & development , Biomarkers/metabolism , Colitis, Ulcerative/diagnosis , Colitis, Ulcerative/microbiology , Double-Blind Method , Fecal Microbiota Transplantation/adverse effects , Feces/microbiology , Humans , Metabolomics , New South Wales , Remission Induction , Ribotyping , Time Factors , Treatment Outcome
9.
Rev Cardiovasc Med ; 21(4): 517-530, 2020 12 30.
Article in English | MEDLINE | ID: mdl-33387997

ABSTRACT

The SARS-CoV-2 virus spreading across the world has led to surges of COVID-19 illness, hospitalizations, and death. The complex and multifaceted pathophysiology of life-threatening COVID-19 illness including viral mediated organ damage, cytokine storm, and thrombosis warrants early interventions to address all components of the devastating illness. In countries where therapeutic nihilism is prevalent, patients endure escalating symptoms and without early treatment can succumb to delayed in-hospital care and death. Prompt early initiation of sequenced multidrug therapy (SMDT) is a widely and currently available solution to stem the tide of hospitalizations and death. A multipronged therapeutic approach includes 1) adjuvant nutraceuticals, 2) combination intracellular anti-infective therapy, 3) inhaled/oral corticosteroids, 4) antiplatelet agents/anticoagulants, 5) supportive care including supplemental oxygen, monitoring, and telemedicine. Randomized trials of individual, novel oral therapies have not delivered tools for physicians to combat the pandemic in practice. No single therapeutic option thus far has been entirely effective and therefore a combination is required at this time. An urgent immediate pivot from single drug to SMDT regimens should be employed as a critical strategy to deal with the large numbers of acute COVID-19 patients with the aim of reducing the intensity and duration of symptoms and avoiding hospitalization and death.


Subject(s)
COVID-19 Drug Treatment , Leprostatic Agents/therapeutic use , Pandemics , SARS-CoV-2 , Telemedicine/methods , COVID-19/epidemiology , Drug Therapy, Combination , Humans
11.
Lancet ; 389(10075): 1218-1228, 2017 03 25.
Article in English | MEDLINE | ID: mdl-28214091

ABSTRACT

BACKGROUND: The intestinal microbiota is implicated in the pathogenesis of ulcerative colitis. Faecal microbiota transplantation is a novel form of therapeutic microbial manipulation, but its efficacy in ulcerative colitis is uncertain. We aimed to establish the efficacy of intensive-dosing, multidonor, faecal microbiota transplantation in active ulcerative colitis. METHODS: We conducted a multicentre, double-blind, randomised, placebo-controlled trial at three hospitals in Australia. We randomly allocated patients with active ulcerative colitis (Mayo score 4-10) in a 1:1 ratio, using a pre-established randomisation list, to either faecal microbiota transplantation or placebo colonoscopic infusion, followed by enemas 5 days per week for 8 weeks. Patients, treating clinicians, and other study staff were unaware of the assigned treatment. Faecal microbiota transplantation enemas were each derived from between three and seven unrelated donors. The primary outcome was steroid-free clinical remission with endoscopic remission or response (Mayo score ≤2, all subscores ≤1, and ≥1 point reduction in endoscopy subscore) at week 8. Analysis was by modified intention-to-treat and included all patients receiving one study dose. We performed 16S rRNA stool analysis to assess associated microbial changes. This trial is registered with ClinicalTrials.gov, number NCT01896635. The trial has ended; this report presents the final analysis. FINDINGS: From November, 2013, to May, 2015, 85 patients were enrolled to our trial, of whom 42 were randomly assigned faecal microbiota transplantation and 43 were allocated placebo. One patient assigned faecal microbiota transplantation and three allocated placebo did not receive study treatment and were excluded from the analysis. The primary outcome was achieved in 11 (27%) of 41 patients allocated faecal microbiota transplantation versus three (8%) of 40 who were assigned placebo (risk ratio 3·6, 95% CI 1·1-11·9; p=0·021). Adverse events were reported by 32 (78%) of 41 patients allocated faecal microbiota transplantation and 33 (83%) of 40 who were assigned placebo; most were self-limiting gastrointestinal complaints, with no significant difference in number or type of adverse events between treatment groups. Serious adverse events occurred in two patients assigned faecal microbiota transplantation and in one allocated placebo. Microbial diversity increased with and persisted after faecal microbiota transplantation. Several bacterial taxa were associated with clinical outcome; in particular, the presence of Fusobacterium spp was associated with lack of remission. INTERPRETATION: Intensive-dosing, multidonor, faecal microbiota transplantation induces clinical remission and endoscopic improvement in active ulcerative colitis and is associated with distinct microbial changes that relate to outcome. Faecal microbiota transplantation is, thus, a promising new therapeutic option for ulcerative colitis. Future work should focus on precisely defining the optimum treatment intensity and the role of donor-recipient matching based on microbial profiles. FUNDING: Broad Medical Research Program, Gastroenterological Society of Australia, Mount Sinai (New York) SUCCESS fund, University of New South Wales.


Subject(s)
Colitis, Ulcerative/therapy , Fecal Microbiota Transplantation/methods , Adult , Colitis, Ulcerative/microbiology , Colonoscopy , Double-Blind Method , Fecal Microbiota Transplantation/adverse effects , Feces/microbiology , Female , Gastrointestinal Microbiome , Humans , Male , Middle Aged , Remission Induction , Severity of Illness Index , Tissue Donors
13.
Gastroenterology ; 145(5): 946-53, 2013 Nov.
Article in English | MEDLINE | ID: mdl-24018052

ABSTRACT

There has been growing interest in the use of fecal microbiota for the treatment of patients with chronic gastrointestinal infections and inflammatory bowel diseases. Lately, there has also been interest in its therapeutic potential for cardiometabolic, autoimmune, and other extraintestinal conditions that were not previously considered to be associated with the intestinal microbiota. Although it is not clear if changes in the microbiota cause these conditions, we review the most current and best methods for performing fecal microbiota transplantation and summarize clinical observations that have implicated the intestinal microbiota in various diseases. We also discuss case reports of fecal microbiota transplantations for different disorders, including Clostridium difficile infection, irritable bowel syndrome, inflammatory bowel diseases, insulin resistance, multiple sclerosis, and idiopathic thrombocytopenic purpura. There has been increasing focus on the interaction between the intestinal microbiome, obesity, and cardiometabolic diseases, and we explore these relationships and the potential roles of different microbial strains. We might someday be able to mine for intestinal bacterial strains that can be used in the diagnosis or treatment of these diseases.


Subject(s)
Enterocolitis, Pseudomembranous/therapy , Feces/microbiology , Gastrointestinal Diseases/therapy , Inflammatory Bowel Diseases/therapy , Microbiota , Transplants , Clostridioides difficile , Enterocolitis, Pseudomembranous/microbiology , Humans , Transplantation, Homologous , Treatment Outcome
14.
Curr Opin Gastroenterol ; 30(1): 97-105, 2014 Jan.
Article in English | MEDLINE | ID: mdl-24257037

ABSTRACT

PURPOSE OF REVIEW: Faecal microbiota transplantation (FMT) has undergone dramatic progression over the past year and continues to evolve as knowledge of the gastrointestinal microbiota (GiMb) develops. This review summarizes therapeutic advances in FMT, latest FMT therapies and presents the potential of FMT therapeutics in other gastrointestinal and extra-intestinal conditions. RECENT FINDINGS: The GiMb is now known to have a central role in the pathogenesis of many diseases. The success of FMT in curing Clostridium difficile infection (CDI) is well established and preliminary findings in other gastrointestinal conditions are promising. Published data from over 500 CDI cases suggest that FMT is generally well tolerated with minimal side effects. The commercial potential of FMT is being explored with several products under development, including frozen GiMb extract, which has been shown highly effective in treating relapsing CDI. Such products will likely become more available in coming years and revolutionize the availability and method of delivery of GiMb. SUMMARY: Recent literature unequivocally supports the use of FMT in treating relapsing CDI. Trials are underway to determine the therapeutic potential of FMT in other conditions, particularly inflammatory bowel disease. Therapeutic FMT is a dynamic field with new and emerging indications along with ongoing developments in optimal mode of administration.


Subject(s)
Feces/microbiology , Intestinal Diseases/therapy , Microbiota , Tissue Transplantation/trends , Autoimmune Diseases/therapy , Enterocolitis, Pseudomembranous/therapy , Humans , Inflammatory Bowel Diseases/therapy , Intestines/microbiology , Irritable Bowel Syndrome/therapy , Recurrence , Tissue Transplantation/methods
15.
Viruses ; 16(4)2024 04 22.
Article in English | MEDLINE | ID: mdl-38675987

ABSTRACT

Consistent with the biochemistry of coronaviruses as well established over decades, SARS-CoV-2 makes its initial attachment to host cells through the binding of its spike protein (SP) to sialylated glycans (containing the monosaccharide sialic acid) on the cell surface. The virus can then slide over and enter via ACE2. SARS-CoV-2 SP attaches particularly tightly to the trillions of red blood cells (RBCs), platelets and endothelial cells in the human body, each cell very densely coated with sialic acid surface molecules but having no ACE2 or minimal ACE2. These interlaced attachments trigger the blood cell aggregation, microvascular occlusion and vascular damage that underlie the hypoxia, blood clotting and related morbidities of severe COVID-19. Notably, the two human betacoronaviruses that express a sialic acid-cleaving enzyme are benign, while the other three-SARS, SARS-CoV-2 and MERS-are virulent. RBC aggregation experimentally induced in several animal species using an injected polysaccharide caused most of the same morbidities of severe COVID-19. This glycan biochemistry is key to disentangling controversies that have arisen over the efficacy of certain generic COVID-19 treatment agents and the safety of SP-based COVID-19 vaccines. More broadly, disregard for the active physiological role of RBCs yields unreliable or erroneous reporting of pharmacokinetic parameters as routinely obtained for most drugs and other bioactive agents using detection in plasma, with whole-blood levels being up to 30-fold higher. Appreciation of the active role of RBCs can elucidate the microvascular underpinnings of other health conditions, including cardiovascular disease, and therapeutic opportunities to address them.


Subject(s)
Microvessels , Polysaccharides , SARS-CoV-2 , Animals , Humans , Angiotensin-Converting Enzyme 2/metabolism , Betacoronavirus/metabolism , COVID-19/metabolism , COVID-19/virology , COVID-19 Drug Treatment , Endothelial Cells/metabolism , Endothelial Cells/virology , Erythrocyte Aggregation , Erythrocytes/metabolism , Erythrocytes/virology , Microvessels/metabolism , Microvessels/virology , Polysaccharides/metabolism , SARS-CoV-2/metabolism , Spike Glycoprotein, Coronavirus/metabolism , Virus Attachment
16.
Nat Commun ; 15(1): 2645, 2024 Mar 26.
Article in English | MEDLINE | ID: mdl-38531874

ABSTRACT

Host molecular responses to fecal microbiota transplantation (FMT) in ulcerative colitis are not well understood. Here, we profile the human colonic mucosal transcriptome prior to and following FMT or placebo to identify molecules regulated during disease remission. FMT alters the transcriptome above the effect of placebo (n = 75 vs 3 genes, q < 0.05), including modulation of structural, metabolic and inflammatory pathways. This response is attributed to responders with no consistency observed in non-responders. Regulated pathways in responders include tight junctions, calcium signalling and xenobiotic metabolism. Genes significantly regulated longitudinally in responders post-FMT could discriminate them from responders and non-responders at baseline and non-responders post-FMT, with GBP5 and IRF4 downregulation being associated with remission. Female mice with a deletion of GBP5 are more resistant to developing colitis than their wild-type littermates, showing higher colonic IRF4 phosphorylation. The colonic mucosal response discriminates UC remission following FMT, with GBP5 playing a detrimental role in colitis.


Subject(s)
Colitis, Ulcerative , Fecal Microbiota Transplantation , Animals , Female , Humans , Mice , Feces , GTP-Binding Proteins , Intestinal Mucosa , Treatment Outcome
17.
Curr Gastroenterol Rep ; 15(8): 337, 2013 Aug.
Article in English | MEDLINE | ID: mdl-23852569

ABSTRACT

Fecal microbiota transplantation (FMT) has attracted great interest in recent years, largely due to the global Clostridium difficile infection (CDI) epidemic and major advances in metagenomic sequencing of the gastrointestinal (GI) microbiota, with growing understanding of its structure and function. FMT is now recommended as the most effective therapy for relapsing CDI and, with further refinement, may even be used in "first-time" CDI. There is interest also in other conditions related to GI dysbiosis--for example, inflammatory bowel disease, irritable bowel syndrome, obesity, and diabetes mellitus--although quality evidence is at present lacking. A few trials are now underway in FMT for ulcerative colitis. Many unanswered questions remain, including FMT methodology--for example, optimal route of administration, what makes a "good donor," safety issues, and long-term effects of FMT.


Subject(s)
Biological Therapy/methods , Enterocolitis, Pseudomembranous/therapy , Feces/microbiology , Inflammatory Bowel Diseases/therapy , Biological Therapy/trends , Evidence-Based Medicine/methods , Gastrointestinal Tract/microbiology , Humans , Irritable Bowel Syndrome/therapy , Microbiota
18.
Cells ; 12(1)2022 12 28.
Article in English | MEDLINE | ID: mdl-36611911

ABSTRACT

Characterized by the presence of amyloid plaques, neurofibrillary tangles and neuroinflammation, Alzheimer's disease (AD) is a progressive neurodegenerative disorder with no known treatment or cure. Global disease projections warrant an urgent and rapid therapeutic for the treatment of this devastating disease. Fecal microbiota transplantation (FMT) is a widely accepted and safely used treatment for recurrent Clostridium difficile infection and other metabolic diseases such as diabetes mellitus. FMT has also been demonstrated to be a possible AD therapeutic. We examined the potential of FMT for the treatment of AD in a robust, mouse model of the disease and report that a brief, 7-day treatment regimen demonstrated 'plaque-busting' and behavior-modifying effects in treated 5xFAD mice. Importantly, we show that donor age plays an important role in the efficacy of the treatment and these findings warrant further investigation in human trials.


Subject(s)
Alzheimer Disease , Clostridioides difficile , Clostridium Infections , Humans , Mice , Animals , Fecal Microbiota Transplantation , Alzheimer Disease/therapy , Clostridium Infections/therapy , Disease Models, Animal , Cognition
19.
Chin Med J (Engl) ; 135(16): 1927-1939, 2022 Aug 20.
Article in English | MEDLINE | ID: mdl-36103991

ABSTRACT

ABSTRACT: Fecal microbiota transplantation (FMT) has been used as a core therapy for treating dysbiosis-related diseases by remodeling gut microbiota. The methodology and technology for improving FMT are stepping forward, mainly including washed microbiota transplantation (WMT), colonic transendoscopic enteral tubing (TET) for microbiota delivery, and purified Firmicutes spores from fecal matter. To improve the understanding of the clinical applications of FMT, we performed a systematic literature review on FMT published from 2011 to 2021. Here, we provided an overview of the reported clinical benefits of FMT, the methodology of processing FMT, the strategy of using FMT, and the regulations on FMT from a global perspective. A total of 782 studies were included for the final analysis. The present review profiled the effectiveness from all clinical FMT uses in 85 specific diseases as eight categories, including infections, gut diseases, microbiota-gut-liver axis, microbiota-gut-brain axis, metabolic diseases, oncology, hematological diseases, and other diseases. Although many further controlled trials will be needed, the dramatic increasing reports have shown the promising future of FMT for dysbiosis-related diseases in the gut or beyond the gut.


Subject(s)
Gastrointestinal Microbiome , Microbiota , Humans , Fecal Microbiota Transplantation/methods , Dysbiosis/therapy , Feces
20.
Gastroenterol Res Pract ; 2022: 6083896, 2022.
Article in English | MEDLINE | ID: mdl-36275423

ABSTRACT

Background: The use of faecal microbiota transplantation (FMT) in irritable bowel syndrome (IBS) has frequently failed to induce long-term symptomatic improvement. The use of multiple FMT infusions is one proposed mechanism through which the efficacy of FMT can be amplified. Aims: To evaluate the safety and efficacy of a novel six-month FMT treatment protocol in IBS. Methods: Patients diagnosed with IBS confirmed by Rome IV Criteria were recruited for single-centre, single-arm, prospective clinical observational study. Participants received one colonoscopically delivered FMT followed by 36 rectal enemas across a six-month period. Validated abdominal symptoms and Short-Form (SF-36) Quality of Life (QOL) questionnaires were collected at baseline, week-12, week-24, and week-56, respectively. Wilcoxon matched-pairs signed-rank tests were conducted to compare differences in abdominal symptom and SF-36 QOL scores over the follow-up timepoints. Statistical significance was set at 5%. Results: Sixty participants diagnosed with IBS [IBS-constipation (n = 27), IBS-diarrhoea (n = 18), and IBS-mixed (n = 15)] received the six-month FMT treatment. IBS symptom severity reduction was achieved in up to 61% of respondents at week-12, 64% of respondents at week-24, and maintained in up to 75% of respondents at week-52. Long-term reduction in symptom severity was associated with an increase in QOL, achieved in up to 64% of respondents at week-52 when compared to baseline. Adverse events were experienced in 28% of participants, though they were both transient and mild in nature. Conclusions: Six-month sustained FMT appears to be both safe and effective in the short- and long-term alleviation of IBS associated symptoms as well as improving participant QOL.

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