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1.
Dermatol Ther (Heidelb) ; 14(2): 391-408, 2024 Feb.
Article in English | MEDLINE | ID: mdl-38175365

ABSTRACT

INTRODUCTION: The skin of patients with atopic dermatitis (AD) is characterised by elevated pH. As a central homeostatic regulator, an increased pH accelerates desquamation and suppresses lipid processing, resulting in diminished skin barrier function. The aim of this study was to determine whether a novel zinc lactobionate emollient cream can strengthen the skin barrier by lowering skin surface pH. METHODS: A double-blind, forearm-controlled cohort study was undertaken in patients with AD. Participants applied the test cream to one forearm and a vehicle cream to the other (randomised allocation) twice daily for 56 days. Skin surface pH and barrier function (primary outcomes) were assessed at baseline and after 28 days and 56 days of treatment, amongst other tests. RESULTS: A total of 23 adults with AD completed the study. During and after treatment, a sustained difference in skin surface pH was observed between areas treated with the test cream and vehicle (4.50 ± 0.38 versus 5.25 ± 0.54, respectively, p < 0.0001). This was associated with significantly reduced transepidermal water loss (TEWL) on the test cream treated areas compared with control (9.71 ± 2.47 versus 11.20 ± 3.62 g/m2/h, p = 0.0005). Improvements in skin barrier integrity, skin sensitivity to sodium lauryl sulphate, skin hydration, and chymotrypsin-like protease activity were all observed at sites treated with the test cream compared with the control. CONCLUSION: Maintenance of an acidic skin surface pH and delivery of physiologic lipids are beneficial for skin health and may help improve AD control by reducing sensitivity to irritants and allergens.

2.
J Allergy Clin Immunol ; 153(3): 732-741.e8, 2024 Mar.
Article in English | MEDLINE | ID: mdl-37926123

ABSTRACT

BACKGROUND: A diagnosis of atopic dermatitis (AD) is common during infancy; however, it is unclear whether differential skin barrier development defines this period and signals disease onset in predisposed individuals. OBJECTIVE: We sought to study (NCT03143504) and assess the feasibility of remote skin testing from birth to monitor skin barrier maturation and model association with an AD diagnosis by age 12 months. METHODS: Biophysical testing and infrared spectroscopy were conducted at the maternity ward and family home. Tape stripping collected samples for desquamatory protease and natural moisturizing factor analysis. The 4 common European filaggrin risk alleles were screened. RESULTS: A total of 128 infants completed the study, with 20% developing mild disease. Significant changes in permeability barrier function, desquamatory protease activity, and molecular composition assessed spectroscopically were observed longitudinally, but only subtle evidence of differential skin barrier development was noted between infant subgroups. Common filaggrin risk alleles were strongly associated with early-onset disease and conferred a significant reduction in natural moisturizing factor and water content by age 4 weeks. Accounting for a family history of atopy, these parameters alongside a greater lipid/protein ratio and reduced chymotrypsin-like activity at birth were associated with AD. Measured in ambient conditions, transepidermal water loss did not signal disease risk at any stage. CONCLUSIONS: Skin barrier dysfunction lacked an acquired modality but was considered proportional to cohort severity and suggests that a portfolio of tests used in a community setting has the potential to improve current AD risk evaluations from birth.


Subject(s)
Dermatitis, Atopic , Infant , Infant, Newborn , Humans , Female , Pregnancy , Dermatitis, Atopic/diagnosis , Cohort Studies , Filaggrin Proteins , Water , Disease Susceptibility , Peptide Hydrolases , Skin
3.
Clin Exp Dermatol ; 2023 Nov 27.
Article in English | MEDLINE | ID: mdl-38011533

ABSTRACT

INTRODUCTION: Atopic dermatitis (AD) is characterised by skin barrier defects often measured by biophysical tools that observe stratum corneum (SC) functional properties. OBJECTIVE: To employ in vivo infrared spectroscopy alongside biophysical measurements to analyse changes in chemical composition of the SC in relation to AD severity. METHODS: We conducted an observational cross-sectional cohort study where attenuated Total Reflection Fourier Transform Infrared (ATR-FTIR) spectroscopy measurements were collected on the forearm alongside surface pH, capacitance, erythema and transepidermal water loss (TEWL) combined with tape stripping (STS) in a cohort of 75 participants; 55 AD patients stratified by phenotypic severity, compared to 20 healthy controls. Common filaggrin (FLG) variant alleles were genotyped. RESULTS: Reduced hydration, elevated TEWL and redness all associated with greater AD severity. Spectral analysis showed a reduction in 1465cm-1 (full width half maximum) and 1340 cm-1 peak areas indicative of less orthorhombic lipid ordering and reduced carboxylate functional groups that correlated with clinical severity (lipid structure r=-0.59, carboxylate peak area r=-0.50). CONCLUSION: ATR-FTIR spectroscopy is a suitable tool for the characterisation of structural skin barrier defects in AD and has potential as a clinical tool for directing individual treatments based on chemical structural deficiencies.

4.
Front Immunol ; 14: 1030395, 2023.
Article in English | MEDLINE | ID: mdl-37283756

ABSTRACT

Healthy host-microbial mutualism with our intestinal microbiota relies to a large degree on compartmentalization and careful regulation of adaptive mucosal and systemic anti-microbial immune responses. However, commensal intestinal bacteria are never exclusively or permanently restricted to the intestinal lumen and regularly reach the systemic circulation. This results in various degrees of commensal bacteremia that needs to be appropriately dealt with by the systemic immune system. While most intestinal commensal bacteria, except for pathobionts or opportunistic pathogen, have evolved to be non-pathogenic, this does not mean that they are non-immunogenic. Mucosal immune adaptation is carefully controlled and regulated to avoid an inflammatory response, but the systemic immune system usually responds differently and more vigorously to systemic bacteremia. Here we show that germ-free mice have increased systemic immune sensitivity and display anti-commensal hyperreactivity in response to the addition of a single defined T helper cell epitope to the outer membrane porin C (OmpC) of a commensal Escherichia coli strain demonstrated by increased E. coli-specific T cell-dependent IgG responses following systemic priming. This increased systemic immune sensitivity was not observed in mice colonized with a defined microbiota at birth indicating that intestinal commensal colonization also regulates systemic, and not only mucosal, anti-commensal responses. The observed increased immunogenicity of the E. coli strain with the modified OmpC protein was not due to a loss of function and associated metabolic changes as a control E. coli strain without OmpC did not display increased immunogenicity.


Subject(s)
Bacteremia , Escherichia coli , Animals , Mice , Intestinal Mucosa , Symbiosis , Intestines , Bacteremia/pathology
5.
BMJ Open ; 13(4): e062279, 2023 04 06.
Article in English | MEDLINE | ID: mdl-37024251

ABSTRACT

INTRODUCTION: Athletes are not immune to mental health issues but are less likely to seek help than non-athletes and experience barriers including lack of access to services, lack of knowledge as to how to access services and negative past experiences for help-seeking. Formal (eg, university counsellors, general practitioners and psychologists) and semi-formal (eg, academic tutor, sports coach and physiotherapist) sources of support provided in healthcare, the sport context and higher education are key places for athletes to seek help for mental health, and there is a need to synthesise the evidence on athletes' access, attitudes to and experiences of these services, to understand how to improve these services specific to athletes' mental health needs. This protocol outlines a scoping review that will be used to map the evidence, identify gaps in the literature and summarise findings on athletes' access, attitudes to and experiences of help-seeking for their mental health. METHODS AND ANALYSIS: The methodological frameworks of Arksey and O'Malley (2005), Levac et al (2010) and the Joanna Briggs Institute (2020 and 2021) were used to inform this scoping review protocol alongside the Preferred Reporting Items for Systematic review and Meta-Analysis Protocols checklist and published scoping review protocols within sport and health. The six stages of Arksey and O'Malley's (2005) framework have been used for this scoping review. The searches were conducted between 30 March 2022 and 3 April 2022 in the following databases: APA PsycINFO (via OVID), Embase (via Ovid), MEDLINE (via Ovid), APA PsycArticles Full Text (via OVID), Web of Science Core Collection, SPORTDiscus (via EBSCO), CINAHL (via EBSCO), Scopus, ProQuest (Education Database), ProQuest (Education Collection), ProQuest (Health & Medical Collection), ProQuest (Nursing & Allied Health database), ProQuest (Psychology Database), ProQuest (Public Health Database) and ProQuest (Sports Medicine & Education). The main inclusion criteria of this review are: papers that focus on past help-seeking behaviour, attitudes towards help-seeking and future behavioural intentions, papers that refer to formal and semi-formal sources of support and peer-reviewed literature, primary research articles, systematic or scoping reviews and interventions. During title and abstract screening and full-text review, at least two reviewers will be involved. Data to be extracted from studies includes: details of the study population, whether the paper focuses on formal and/or semi-formal sources of support and whether the focus is on access, attitudes or experiences to help-seeking for mental health. ETHICS AND DISSEMINATION: The evidence will be mapped numerically and through content analysis to describe studies and highlight key concepts, themes and gaps in the literature. The published scoping review will be disseminated to relevant stakeholders and policymakers including those in healthcare, the sporting context and the higher education system. The resulting outputs will be in the form of both peer-reviewed and non-peer reviewed publications (eg, multimedia in the form of a blog post and at conferences). The dissemination plan will be informed by patient and public involvement. Ethics approval was not required for this study.


Subject(s)
General Practitioners , Sports , Humans , Mental Health , Educational Status , Research Design , Review Literature as Topic , Meta-Analysis as Topic
6.
Nat Commun ; 14(1): 1348, 2023 03 11.
Article in English | MEDLINE | ID: mdl-36906623

ABSTRACT

Commensal bacteria are major contributors to mammalian metabolism. We used liquid chromatography mass spectrometry to study the metabolomes of germ-free, gnotobiotic, and specific-pathogen-free mice, while also evaluating the influence of age and sex on metabolite profiles. Microbiota modified the metabolome of all body sites and accounted for the highest proportion of variation within the gastrointestinal tract. Microbiota and age explained similar amounts of variation the metabolome of urine, serum, and peritoneal fluid, while age was the primary driver of variation in the liver and spleen. Although sex explained the least amount of variation at all sites, it had a significant impact on all sites except the ileum. Collectively, these data illustrate the interplay between microbiota, age, and sex in the metabolic phenotypes of diverse body sites. This provides a framework for interpreting complex metabolic phenotypes and will help guide future studies into the role that the microbiome plays in disease.


Subject(s)
Metabolome , Microbiota , Mice , Animals , Gastrointestinal Tract/microbiology , Germ-Free Life , Specific Pathogen-Free Organisms , Metabolomics/methods , Mammals
7.
Article in English | MEDLINE | ID: mdl-36834176

ABSTRACT

BACKGROUND: Post-viral syndromes (PVS), including Long COVID, are symptoms sustained from weeks to years following an acute viral infection. Non-pharmacological treatments for these symptoms are poorly understood. This review summarises the evidence for the effectiveness of non-pharmacological treatments for PVS. METHODS: We conducted a systematic review to evaluate the effectiveness of non-pharmacological interventions for PVS, as compared to either standard care, alternative non-pharmacological therapy, or placebo. The outcomes of interest were changes in symptoms, exercise capacity, quality of life (including mental health and wellbeing), and work capability. We searched five databases (Embase, MEDLINE, PsycINFO, CINAHL, MedRxiv) for randomised controlled trials (RCTs) published between 1 January 2001 to 29 October 2021. The relevant outcome data were extracted, the study quality was appraised using the Cochrane risk-of-bias tool, and the findings were synthesised narratively. FINDINGS: Overall, five studies of five different interventions (Pilates, music therapy, telerehabilitation, resistance exercise, neuromodulation) met the inclusion criteria. Aside from music-based intervention, all other selected interventions demonstrated some support in the management of PVS in some patients. INTERPRETATION: In this study, we observed a lack of robust evidence evaluating the non-pharmacological treatments for PVS, including Long COVID. Considering the prevalence of prolonged symptoms following acute viral infections, there is an urgent need for clinical trials evaluating the effectiveness and cost-effectiveness of non-pharmacological treatments for patients with PVS. REGISTRATION: The study protocol was registered with PROSPERO [CRD42021282074] in October 2021 and published in BMJ Open in 2022.


Subject(s)
COVID-19 , Virus Diseases , Humans , Post-Acute COVID-19 Syndrome , Mental Health
8.
Int Urogynecol J ; 34(6): 1219-1225, 2023 06.
Article in English | MEDLINE | ID: mdl-36040505

ABSTRACT

INTRODUCTION AND HYPOTHESIS: During the COVID-19 pandemic, guidance was issued in the United Kingdom advising a delay in routine pessary reviews. The impact of this has not been fully explored. The null hypothesis for this study is that delayed routine pessary reviews during the COVID-19 pandemic did not result in a statistically significant increase in complication rate. METHODS: A retrospective comparative cohort study was conducted in NHS Tayside, Scotland, involving 150 patients pre-pandemic and 150 patients during the COVID-19 pandemic (before exclusions). Their notes were reviewed identifying age, care provider, pessary type, length of pessary usage, review date, time elapsed since the previous review, bleeding/infection/ulceration, removal issues, pessary replacement and outcome. Patients excluded were those with no pessary in situ at review, reviews at ≤4 months and >8 months (pre-pandemic) and reviews at ≤8 months (COVID-19 pandemic). RESULTS: The pre-pandemic group (n=106) had average review times of 10.1,6.2 and 6.2 months for cubes, rings and all others. Overall rates of bleeding/infection/ulceration; reported removal issues; and pessary subsequently not replaced were 9.4%, 11.3% and 5.7% respectively. The COVID-19 pandemic group (n=125) had average review times of 14.7, 10.8 and 11.4 months for cubes, rings and all others. Overall rates of bleeding/infection/ulceration; reported removal issues; and pessary subsequently not replaced were 21.6%, 16.0%, and 12.0% respectively. CONCLUSIONS: Overall, there was a significant increase in rates of bleeding/ulceration/infection (p=0.01). When individual pessaries were considered, this only remained true for rings (p=0.02). Our data would suggest that routine ring pessary reviews should not be extended beyond 6 months or risk bleeding/ulceration/infection.


Subject(s)
COVID-19 , Pelvic Organ Prolapse , Humans , Pelvic Organ Prolapse/therapy , Pelvic Organ Prolapse/etiology , Pandemics , Pessaries/adverse effects , Retrospective Studies , Cohort Studies , COVID-19/epidemiology , Hemorrhage/etiology
9.
Nat Med ; 28(8): 1706-1714, 2022 08.
Article in English | MEDLINE | ID: mdl-35879616

ABSTRACT

Severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) infection is associated with a range of persistent symptoms impacting everyday functioning, known as post-COVID-19 condition or long COVID. We undertook a retrospective matched cohort study using a UK-based primary care database, Clinical Practice Research Datalink Aurum, to determine symptoms that are associated with confirmed SARS-CoV-2 infection beyond 12 weeks in non-hospitalized adults and the risk factors associated with developing persistent symptoms. We selected 486,149 adults with confirmed SARS-CoV-2 infection and 1,944,580 propensity score-matched adults with no recorded evidence of SARS-CoV-2 infection. Outcomes included 115 individual symptoms, as well as long COVID, defined as a composite outcome of 33 symptoms by the World Health Organization clinical case definition. Cox proportional hazards models were used to estimate adjusted hazard ratios (aHRs) for the outcomes. A total of 62 symptoms were significantly associated with SARS-CoV-2 infection after 12 weeks. The largest aHRs were for anosmia (aHR 6.49, 95% CI 5.02-8.39), hair loss (3.99, 3.63-4.39), sneezing (2.77, 1.40-5.50), ejaculation difficulty (2.63, 1.61-4.28) and reduced libido (2.36, 1.61-3.47). Among the cohort of patients infected with SARS-CoV-2, risk factors for long COVID included female sex, belonging to an ethnic minority, socioeconomic deprivation, smoking, obesity and a wide range of comorbidities. The risk of developing long COVID was also found to be increased along a gradient of decreasing age. SARS-CoV-2 infection is associated with a plethora of symptoms that are associated with a range of sociodemographic and clinical risk factors.


Subject(s)
COVID-19 , Adult , COVID-19/complications , COVID-19/epidemiology , Cohort Studies , Ethnicity , Female , Humans , Male , Minority Groups , Retrospective Studies , Risk Factors , SARS-CoV-2 , Post-Acute COVID-19 Syndrome
10.
BMJ Open ; 12(4): e060413, 2022 04 26.
Article in English | MEDLINE | ID: mdl-35473737

ABSTRACT

INTRODUCTION: Individuals with COVID-19 frequently experience symptoms and impaired quality of life beyond 4-12 weeks, commonly referred to as Long COVID. Whether Long COVID is one or several distinct syndromes is unknown. Establishing the evidence base for appropriate therapies is needed. We aim to evaluate the symptom burden and underlying pathophysiology of Long COVID syndromes in non-hospitalised individuals and evaluate potential therapies. METHODS AND ANALYSIS: A cohort of 4000 non-hospitalised individuals with a past COVID-19 diagnosis and 1000 matched controls will be selected from anonymised primary care records from the Clinical Practice Research Datalink, and invited by their general practitioners to participate on a digital platform (Atom5). Individuals will report symptoms, quality of life, work capability and patient-reported outcome measures. Data will be collected monthly for 1 year.Statistical clustering methods will be used to identify distinct Long COVID-19 symptom clusters. Individuals from the four most prevalent clusters and two control groups will be invited to participate in the BioWear substudy which will further phenotype Long COVID symptom clusters by measurement of immunological parameters and actigraphy.We will review existing evidence on interventions for postviral syndromes and Long COVID to map and prioritise interventions for each newly characterised Long COVID syndrome. Recommendations will be made using the cumulative evidence in an expert consensus workshop. A virtual supportive intervention will be coproduced with patients and health service providers for future evaluation.Individuals with lived experience of Long COVID will be involved throughout this programme through a patient and public involvement group. ETHICS AND DISSEMINATION: Ethical approval was obtained from the Solihull Research Ethics Committee, West Midlands (21/WM/0203). Research findings will be presented at international conferences, in peer-reviewed journals, to Long COVID patient support groups and to policymakers. TRIAL REGISTRATION NUMBER: 1567490.


Subject(s)
COVID-19 , COVID-19/complications , COVID-19/therapy , COVID-19 Testing , Humans , Patient Reported Outcome Measures , Quality of Life , Syndrome , Post-Acute COVID-19 Syndrome
11.
BMJ Open ; 12(4): e057885, 2022 04 11.
Article in English | MEDLINE | ID: mdl-35410933

ABSTRACT

INTRODUCTION: Postviral syndromes (PVS) describe the sustained presence of symptoms following an acute viral infection, for months or even years. Exposure to the SARS-CoV-2 virus and subsequent development of COVID-19 has shown to have similar effects with individuals continuing to exhibit symptoms for greater than 12 weeks. The sustained presence of symptoms is variably referred to as 'post COVID-19 syndrome', 'post-COVID condition' or more commonly 'Long COVID'. Knowledge of the long-term health impacts and treatments for Long COVID are evolving. To minimise overlap with existing work in the field exploring treatments of Long COVID, we have only chosen to focus on non-pharmacological treatments. AIMS: This review aims to summarise the effectiveness of non-pharmacological treatments for PVS, including Long COVID. A secondary aim is to summarise the symptoms and health impacts associated with PVS in individuals recruited to treatment studies. METHODS AND ANALYSIS: Primary electronic searches will be performed in bibliographic databases including: Embase, MEDLINE, PyscINFO, CINAHL and MedRxiv from 1 January 2001 to 29 October 2021. At least two independent reviewers will screen each study for inclusion and data will be extracted from all eligible studies onto a data extraction form. The quality of all included studies will be assessed using Cochrane risk of bias tools and the Newcastle-Ottawa grading system. Non-pharmacological treatments for PVS and Long COVID will be narratively summarised and effect estimates will be pooled using random effects meta-analysis where there is sufficient methodological homogeneity. The symptoms and health impacts reported in the included studies on non-pharmacological interventions will be extracted and narratively reported. ETHICS AND DISSEMINATION: This systematic review does not require ethical approval. The findings from this study will be submitted for peer-reviewed publication, shared at conference presentations and disseminated to both clinical and patient groups. PROSPERO REGISTRATION NUMBER: The review will adhere to this protocol which has also been registered with PROSPERO (CRD42021282074).


Subject(s)
COVID-19 , Bias , COVID-19/complications , COVID-19/therapy , Humans , Meta-Analysis as Topic , Research Design , SARS-CoV-2 , Syndrome , Systematic Reviews as Topic , Post-Acute COVID-19 Syndrome
13.
Br J Dermatol ; 186(5): 875-886, 2022 05.
Article in English | MEDLINE | ID: mdl-34921679

ABSTRACT

BACKGROUND: The skin of patients with atopic dermatitis is characterized by abnormal stratum corneum lipid levels. Consequently, the lamellar matrices are disrupted and skin barrier function is diminished, increasing skin sensitivity to irritants and allergens. OBJECTIVES: To determine whether a cream containing ceramides, triglycerides and cholesterol in a multivesicular emulsion can reinforce the skin barrier and protect against skin irritation. METHODS: A randomized observer-blind intrapatient-controlled study in 34 adults with dry, eczema-prone skin was conducted. Each participant underwent 4 weeks of treatment with the test cream on one forearm and lower leg and a reference emollient cream on the other. Skin properties were determined before and after treatment. Lipid structure was assessed by Fourier-transform infrared spectroscopy using a novel interface. RESULTS: Skin barrier integrity was greater at sites treated with the test cream [effect size for area under the transepidermal water loss curve -162, 95% confidence interval (CI) -206 to -118]. Skin sensitivity to sodium lauryl sulfate was reduced (-0·5 points visual redness, 97·57% CI -1·00 to -0·25), as was transepidermal water loss (-15·3 g m-2 h-1 , 95% CI -20·3 to -10·4) compared with the reference. Sites treated with the test cream displayed enhanced lipid chain ordering, which was significantly associated with skin barrier integrity (r = 0·61). Compared with the reference, treatment with the test cream increased hydration (8·61 capacitance units, 95% CI 6·61-10·6) and decreased signs of dryness. CONCLUSIONS: The test cream facilitates skin barrier restoration and protects the skin from dryness and irritation. Compared with a commonly prescribed emollient in the UK, the test cream is highly suited to the management of dry, sensitive skin.


Subject(s)
Eczema , Skin Abnormalities , Adult , Eczema/drug therapy , Eczema/prevention & control , Emollients/therapeutic use , Humans , Skin , Skin Abnormalities/drug therapy , Sodium Dodecyl Sulfate/pharmacology , Water , Water Loss, Insensible
15.
Oncoimmunology ; 10(1): 1945202, 2021.
Article in English | MEDLINE | ID: mdl-34367729

ABSTRACT

Squamous cell carcinoma of the tonsil is one of the most frequent cancers of the oropharynx. The escalating rate of tonsil cancer during the last decades is associated with the increase of high risk-human papilloma virus (HR-HPV) infections. While the microbiome in oropharyngeal malignant diseases has been characterized to some extent, the microbial colonization of HR-HPV-associated tonsil cancer remains largely unknown. Using 16S rRNA gene amplicon sequencing, we have characterized the microbiome of human palatine tonsil crypts in patients suffering from HR-HPV-associated tonsil cancer in comparison to a control cohort of adult sleep apnea patients. We found an increased abundance of the phyla Firmicutes and Actinobacteria in tumor patients, whereas the abundance of Spirochetes and Synergistetes was significantly higher in the control cohort. Furthermore, the accumulation of several genera such as Veillonella, Streptococcus and Prevotella_7 in tonsillar crypts was associated with tonsil cancer. In contrast, Fusobacterium, Prevotella and Treponema_2 were enriched in sleep apnea patients. Machine learning-based bacterial species analysis indicated that a particular bacterial composition in tonsillar crypts is tumor-predictive. Species-specific PCR-based validation in extended patient cohorts confirmed that differential abundance of Filifactor alocis and Prevotella melaninogenica is a distinct trait of tonsil cancer. This study shows that tonsil cancer patients harbor a characteristic microbiome in the crypt environment that differs from the microbiome of sleep apnea patients on all phylogenetic levels. Moreover, our analysis indicates that profiling of microbial communities in distinct tonsillar niches provides microbiome-based avenues for the diagnosis of tonsil cancer.


Subject(s)
Carcinoma, Squamous Cell , Microbiota , Tonsillar Neoplasms , Clostridiales , Humans , Microbiota/genetics , Phylogeny , RNA, Ribosomal, 16S/genetics
16.
Cell Host Microbe ; 28(5): 660-668.e4, 2020 11 11.
Article in English | MEDLINE | ID: mdl-32810440

ABSTRACT

Eradication of pathogens from the bloodstream is critical to prevent disseminated infections and sepsis. Kupffer cells in the liver form an intravascular firewall that captures and clears pathogens from the blood. Here, we show that the catching and killing of circulating pathogens by Kupffer cells in vivo are promoted by the gut microbiota through commensal-derived D-lactate that reaches the liver via the portal vein. The integrity of this Kupffer cell-mediated intravascular firewall requires continuous crosstalk with gut commensals, as microbiota depletion with antibiotics leads to a failure of pathogen clearance and overwhelming disseminated infection. Furthermore, administration of purified D-lactate to germ-free mice, or gnotobiotic colonization with D-lactate-producing commensals, restores Kupffer cell-mediated pathogen clearance by the liver firewall. Thus, the gut microbiota programs an intravascular immune firewall that protects against the spread of bacterial infections via the bloodstream.


Subject(s)
Anti-Bacterial Agents/pharmacology , Bacterial Infections/drug therapy , Gastrointestinal Microbiome/immunology , Protective Agents/pharmacology , Animals , Bacteria , Bacterial Infections/microbiology , Dysbiosis , Germ-Free Life , Kupffer Cells , Lactobacillus , Liver/microbiology , Mice , Mice, Inbred C57BL , Sepsis , Staphylococcus aureus , Symbiosis
17.
Science ; 369(6510): 1481-1489, 2020 09 18.
Article in English | MEDLINE | ID: mdl-32792462

ABSTRACT

Several species of intestinal bacteria have been associated with enhanced efficacy of checkpoint blockade immunotherapy, but the underlying mechanisms by which the microbiome enhances antitumor immunity are unclear. In this study, we isolated three bacterial species-Bifidobacterium pseudolongum, Lactobacillus johnsonii, and Olsenella species-that significantly enhanced efficacy of immune checkpoint inhibitors in four mouse models of cancer. We found that intestinal B. pseudolongum modulated enhanced immunotherapy response through production of the metabolite inosine. Decreased gut barrier function induced by immunotherapy increased systemic translocation of inosine and activated antitumor T cells. The effect of inosine was dependent on T cell expression of the adenosine A2A receptor and required costimulation. Collectively, our study identifies a previously unknown microbial metabolite immune pathway activated by immunotherapy that may be exploited to develop microbial-based adjuvant therapies.


Subject(s)
Bifidobacterium/metabolism , Gastrointestinal Microbiome , Immunotherapy , Inosine/metabolism , Intestinal Neoplasms/therapy , Lactobacillus johnsonii/metabolism , Melanoma/therapy , Skin Neoplasms/therapy , Urinary Bladder Neoplasms/therapy , Animals , Antibodies/therapeutic use , B7-H1 Antigen/antagonists & inhibitors , B7-H1 Antigen/immunology , CTLA-4 Antigen/antagonists & inhibitors , CTLA-4 Antigen/immunology , Female , Male , Mice , Mice, Inbred C57BL , Neoplasms, Experimental/therapy , Receptor, Adenosine A2A/metabolism , T-Lymphocytes/immunology
18.
Dermatol Ther (Heidelb) ; 10(5): 1031-1041, 2020 Oct.
Article in English | MEDLINE | ID: mdl-32671664

ABSTRACT

INTRODUCTION: The replenishment of skin lipids depleted in the dry skin state is a desirable therapeutic target to restore skin moisturization; however, there is limited evidence demonstrating the success of this approach through the use of topical emollients. The purpose of this study was to provide evidence of the benefits of a cream and equivalent lotion containing skin lipids in a multi-vesicular emulsion for the management of dry skin. The hypothesis was that the test cream and test lotion could sustain skin moisturization for longer than traditional emollients by sustainably delivering skin lipids. METHODS: A double-blind intra-subject vehicle-controlled single open-application test on the lower legs in people with dry, atopic dermatitis (atopic eczema)-prone, skin was conducted. There were six treatment sites, three per lower leg in each participant, which were treated with the test cream, the test lotion, three reference creams commonly prescribed in the UK and no treatment as a control. After baseline measurements of skin hydration, 100 µl of the test/reference creams was applied to each of the relevant treatment sites (random site allocation). Following treatment, measurements of skin hydration and scoring of visual dryness was conducted at timed intervals (3, 6, 12 and 24 h post-product application). RESULTS: The test cream and lotion both significantly increased skin hydration and reduced skin dryness for at least 24 h following a single application compared to a no treatment control site. Compared to three reference emollient creams the test cream and test lotion were the only products capable of sustaining clinically meaningful improvements in skin moisturization for 24 h. CONCLUSION: The sustained moisturization imparted by the test products reduces the need for frequent emollient application, often requiring 3-4 applications per day for traditional emollients, and should reduce the high burden of managing dry skin conditions like atopic dermatitis.

19.
Nat Commun ; 11(1): 1329, 2020 03 12.
Article in English | MEDLINE | ID: mdl-32165624

ABSTRACT

While the ontogeny and recruitment of the intestinal monocyte/macrophage lineage has been studied extensively, their precise localization and function has been overlooked. Here we show by imaging the murine small and large intestines in steady-state that intestinal CX3CR1+ macrophages form an interdigitated network intimately adherent to the entire mucosal lamina propria vasculature. The macrophages form contacts with each other, which are disrupted in the absence of microbiome, monocyte recruitment (Ccr2-/-), or monocyte conversion (Nr4a1-/-). In dysbiosis, gaps exist between the perivascular macrophages correlating with increased bacterial translocation from the lamina propria into the bloodstream. The recruitment of monocytes and conversion to macrophages during intestinal injury is also dependent upon CCR2, Nr4a1 and the microbiome. These findings demonstrate a relationship between microbiome and the maturation of lamina propria perivascular macrophages into a tight anatomical barrier that might function to prevent bacterial translocation. These cells are also critical for emergency vascular repair.


Subject(s)
Gastrointestinal Microbiome , Intestinal Mucosa/blood supply , Intestinal Mucosa/cytology , Macrophages/metabolism , Nuclear Receptor Subfamily 4, Group A, Member 1/metabolism , Animals , CX3C Chemokine Receptor 1/metabolism , Colitis/pathology , Dextran Sulfate , Dysbiosis/pathology , Mice, Inbred C57BL , Monocytes/metabolism , Receptors, CCR2/metabolism , Wound Healing
20.
Nutrients ; 11(2)2019 Feb 16.
Article in English | MEDLINE | ID: mdl-30781503

ABSTRACT

The dynamics of the tripartite relationship between the host, gut bacteria and diet in the gut is relatively unknown. An imbalance between harmful and protective gut bacteria, termed dysbiosis, has been linked to many diseases and has most often been attributed to high-fat dietary intake. However, we recently clarified that the type of fat, not calories, were important in the development of murine colitis. To further understand the host-microbe dynamic in response to dietary lipids, we fed mice isocaloric high-fat diets containing either milk fat, corn oil or olive oil and performed 16S rRNA gene sequencing of the colon microbiome and mass spectrometry-based relative quantification of the colonic metaproteome. The corn oil diet, rich in omega-6 polyunsaturated fatty acids, increased the potential for pathobiont survival and invasion in an inflamed, oxidized and damaged gut while saturated fatty acids promoted compensatory inflammatory responses involved in tissue healing. We conclude that various lipids uniquely alter the host-microbe interaction in the gut. While high-fat consumption has a distinct impact on the gut microbiota, the type of fatty acids alters the relative microbial abundances and predicted functions. These results support that the type of fat are key to understanding the biological effects of high-fat diets on gut health.


Subject(s)
Dietary Fats/administration & dosage , Fats/chemistry , Fatty Acids/chemistry , Gastrointestinal Microbiome/genetics , Intestinal Mucosa/microbiology , Animals , Colon/microbiology , Corn Oil/administration & dosage , Diet, High-Fat/methods , Female , Male , Mice , Mice, Inbred C57BL , Milk/chemistry , Olive Oil/administration & dosage , RNA, Ribosomal, 16S/analysis
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