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1.
Nat Immunol ; 24(12): 2091-2107, 2023 Dec.
Article in English | MEDLINE | ID: mdl-37945820

ABSTRACT

Regulatory T (Treg) cell modulation of adaptive immunity and tissue homeostasis is well described; however, less is known about Treg cell-mediated regulation of the innate immune response. Here we show that deletion of ST2, the receptor for interleukin (IL)-33, on Treg cells increased granulocyte influx into the lung and increased cytokine production by innate lymphoid and γδ T cells without alteration of adaptive immunity to influenza. IL-33 induced high levels of the interleukin-1 receptor antagonist (IL-1Ra) in ST2+ Treg cells and deletion of IL-1Ra in Treg cells increased granulocyte influx into the lung. Treg cell-specific deletion of ST2 or IL-1Ra improved survival to influenza, which was dependent on IL-1. Adventitial fibroblasts in the lung expressed high levels of the IL-1 receptor and their chemokine production was suppressed by Treg cell-produced IL-1Ra. Thus, we define a new pathway where IL-33-induced IL-1Ra production by tissue Treg cells suppresses IL-1-mediated innate immune responses to respiratory viral infection.


Subject(s)
Influenza, Human , T-Lymphocytes, Regulatory , Humans , Immunity, Innate , Interleukin 1 Receptor Antagonist Protein , Interleukin-1/genetics , Interleukin-1 Receptor-Like 1 Protein/genetics , Interleukin-33/metabolism , Lymphocytes/metabolism , Animals , Mice
2.
Immunity ; 49(3): 449-463.e6, 2018 09 18.
Article in English | MEDLINE | ID: mdl-30170811

ABSTRACT

The migration of mature dendritic cells (DCs) into the draining lymph node (dLN) is thought to depend solely on the chemokine receptor CCR7. CD301b+ DCs migrate into the dLN after cutaneous allergen exposure and are required for T helper 2 (Th2) differentiation. We found that CD301b+ DCs poorly upregulated CCR7 expression after allergen exposure and required a second chemokine signal, mediated by CCR8 on CD301b+ DCs and its ligand CCL8, to exit the subcapsular sinus (SCS) and enter the lymph node (LN) parenchyma. After allergen exposure, CD169+SIGN-R1+ macrophages in interfollicular regions produced CCL8, which synergized with CCL21 in a Src-kinase-dependent manner to promote CD301b+ DC migration. In CCR8-deficient mice, CD301b+ DCs remained in the SCS and were unable to enter the LN parenchyma, resulting in defective Th2 differentiation. We have defined a CCR8-dependent stepwise mechanism of DC-subset-specific migration through which LN CD169+SIGN-R1+ macrophages control the polarization of the adaptive immune response.


Subject(s)
Dendritic Cells/physiology , Hypersensitivity/immunology , Lymph Nodes/immunology , Receptors, CCR7/metabolism , Receptors, CCR8/metabolism , Animals , Antigens, CD/metabolism , Cell Movement , Cells, Cultured , Chemokine CCL8/metabolism , Disease Models, Animal , Female , Integrin alpha Chains/metabolism , Lymphocyte Activation , Male , Mice , Mice, Inbred C57BL , Mice, Knockout , Receptors, CCR8/genetics
3.
Proc Natl Acad Sci U S A ; 120(14): e2219124120, 2023 04 04.
Article in English | MEDLINE | ID: mdl-36976762

ABSTRACT

DNA duplex stability arises from cooperative interactions between multiple adjacent nucleotides that favor base pairing and stacking when formed as a continuous stretch rather than individually. Lesions and nucleobase modifications alter this stability in complex manners that remain challenging to understand despite their centrality to biology. Here, we investigate how an abasic site destabilizes small DNA duplexes and reshapes base pairing dynamics and hybridization pathways using temperature-jump infrared spectroscopy and coarse-grained molecular dynamics simulations. We show how an abasic site splits the cooperativity in a short duplex into two segments, which destabilizes small duplexes as a whole and enables metastable half-dissociated configurations. Dynamically, it introduces an additional barrier to hybridization by constraining the hybridization mechanism to a step-wise process of nucleating and zipping a stretch on one side of the abasic site and then the other.


Subject(s)
DNA , Nucleotides , Base Pairing , Nucleic Acid Conformation , DNA/metabolism , Nucleic Acid Hybridization
4.
Proc Natl Acad Sci U S A ; 120(42): e2312462120, 2023 10 17.
Article in English | MEDLINE | ID: mdl-37824523

ABSTRACT

Humans may retrieve words from memory by exploring and exploiting in "semantic space" similar to how nonhuman animals forage for resources in physical space. This has been studied using the verbal fluency test (VFT), in which participants generate words belonging to a semantic or phonetic category in a limited time. People produce bursts of related items during VFT, referred to as "clustering" and "switching." The strategic foraging model posits that cognitive search behavior is guided by a monitoring process which detects relevant declines in performance and then triggers the searcher to seek a new patch or cluster in memory after the current patch has been depleted. An alternative body of research proposes that this behavior can be explained by an undirected rather than strategic search process, such as random walks with or without random jumps to new parts of semantic space. This study contributes to this theoretical debate by testing for neural evidence of strategically timed switches during memory search. Thirty participants performed category and letter VFT during functional MRI. Responses were classified as cluster or switch events based on computational metrics of similarity and participant evaluations. Results showed greater hippocampal and posterior cerebellar activation during switching than clustering, even while controlling for interresponse times and linguistic distance. Furthermore, these regions exhibited ramping activity which increased during within-patch search leading up to switches. Findings support the strategic foraging model, clarifying how neural switch processes may guide memory search in a manner akin to foraging in patchy spatial environments.


Subject(s)
Phonetics , Semantics , Animals , Humans , Verbal Behavior/physiology , Neuropsychological Tests
5.
J Immunol ; 210(12): 1950-1961, 2023 06 15.
Article in English | MEDLINE | ID: mdl-37093656

ABSTRACT

Initial TCR affinity for peptide Ag is known to impact the generation of memory; however, its contributions later, when effectors must again recognize Ag at 5-8 d postinfection to become memory, is unclear. We examined whether the effector TCR affinity for peptide at this "effector checkpoint" dictates the extent of memory and degree of protection against rechallenge. We made an influenza A virus nucleoprotein (NP)-specific TCR transgenic mouse strain, FluNP, and generated NP-peptide variants that are presented by MHC class II to bind to the FluNP TCR over a broad range of avidity. To evaluate the impact of avidity in vivo, we primed naive donor FluNP in influenza A virus-infected host mice, purified donor effectors at the checkpoint, and cotransferred them with the range of peptides pulsed on activated APCs into second uninfected hosts. Higher-avidity peptides yielded higher numbers of FluNP memory cells in spleen and most dramatically in lung and draining lymph nodes and induced better protection against lethal influenza infection. Avidity determined memory cell number, not cytokine profile, and already impacted donor cell number within several days of transfer. We previously found that autocrine IL-2 production at the checkpoint prevents default effector apoptosis and supports memory formation. Here, we find that peptide avidity determines the level of IL-2 produced by these effectors and that IL-2Rα expression by the APCs enhances memory formation, suggesting that transpresentation of IL-2 by APCs further amplifies IL-2 availability. Secondary memory generation was also avidity dependent. We propose that this regulatory pathway selects CD4 effectors of highest affinity to progress to memory.


Subject(s)
CD4-Positive T-Lymphocytes , Interleukin-2 , Mice , Animals , CD4-Positive T-Lymphocytes/metabolism , Interleukin-2/metabolism , Peptides/metabolism , Mice, Transgenic , Receptors, Antigen, T-Cell/metabolism , Immunologic Memory , Mice, Inbred C57BL
6.
Nature ; 569(7757): 503-508, 2019 05.
Article in English | MEDLINE | ID: mdl-31068700

ABSTRACT

Large panels of comprehensively characterized human cancer models, including the Cancer Cell Line Encyclopedia (CCLE), have provided a rigorous framework with which to study genetic variants, candidate targets, and small-molecule and biological therapeutics and to identify new marker-driven cancer dependencies. To improve our understanding of the molecular features that contribute to cancer phenotypes, including drug responses, here we have expanded the characterizations of cancer cell lines to include genetic, RNA splicing, DNA methylation, histone H3 modification, microRNA expression and reverse-phase protein array data for 1,072 cell lines from individuals of various lineages and ethnicities. Integration of these data with functional characterizations such as drug-sensitivity, short hairpin RNA knockdown and CRISPR-Cas9 knockout data reveals potential targets for cancer drugs and associated biomarkers. Together, this dataset and an accompanying public data portal provide a resource for the acceleration of cancer research using model cancer cell lines.


Subject(s)
Cell Line, Tumor , Neoplasms/genetics , Neoplasms/pathology , Antineoplastic Agents/pharmacology , Biomarkers, Tumor , DNA Methylation , Drug Resistance, Neoplasm , Ethnicity/genetics , Gene Editing , Histones/metabolism , Humans , MicroRNAs/genetics , Molecular Targeted Therapy , Neoplasms/metabolism , Protein Array Analysis , RNA Splicing
7.
J Med Genet ; 2024 Sep 03.
Article in English | MEDLINE | ID: mdl-39227160

ABSTRACT

BACKGROUND: The 2015 American College of Medical Genetics/Association of Molecular Pathology (ACMG/AMP) variant classification framework specifies that case-control observations can be scored as 'strong' evidence (PS4) towards pathogenicity. METHODS: We developed the PS4-likelihood ratio calculator (PS4-LRCalc) for quantitative evidence assignment based on the observed variant frequencies in cases and controls. Binomial likelihoods are computed for two models, each defined by prespecified OR thresholds. Model 1 represents the hypothesis of association between variant and phenotype (eg, OR≥5) and model 2 represents the hypothesis of non-association (eg, OR≤1). RESULTS: PS4-LRCalc enables continuous quantitation of evidence for variant classification expressed as a likelihood ratio (LR), which can be log-converted into log LR (evidence points). Using PS4-LRCalc, observed data can be used to quantify evidence towards either pathogenicity or benignity. Variants can also be evaluated against models of different penetrance. The approach is applicable to balanced data sets generated for more common phenotypes and smaller data sets more typical in very rare disease variant evaluation. CONCLUSION: PS4-LRCalc enables flexible evidence quantitation on a continuous scale for observed case-control data. The converted LR is amenable to incorporation into the now widely used 2018 updated Bayesian ACMG/AMP framework.

8.
Proc Natl Acad Sci U S A ; 119(8)2022 02 22.
Article in English | MEDLINE | ID: mdl-35177472

ABSTRACT

While influenza infection induces robust, long-lasting, antibody responses and protection, including the T follicular helper cells (TFH) required to drive B cell germinal center (GC) responses, most influenza vaccines do not. We investigated the mechanisms that drive strong TFH responses during infection. Infection induces viral replication and antigen (Ag) presentation lasting through the CD4 effector phase, but Ag and pathogen recognition receptor signals are short-lived after vaccination. We analyzed the need for both infection and Ag presentation at the effector phase, using an in vivo sequential transfer model to time their availability. Differentiation of CD4 effectors into TFH and GC-TFH required that they recognize Ag locally in the site of TFH development, at the effector phase, but did not depend on specific Ag-presenting cells (APCs). In addition, concurrent signals from infection were necessary even when sufficient Ag was presented. Providing these signals with a second dose of live attenuated influenza vaccine at the effector phase drove TFH and GC-TFH development equivalent to live infection. The results suggest that vaccine approaches can induce strong TFH development that supports GC responses akin to infection, if they supply these effector phase signals at the right time and site. We suggest that these requirements create a checkpoint that ensures TFH only develop fully when infection is still ongoing, thereby avoiding unnecessary, potentially autoimmune, responses.


Subject(s)
Influenza Vaccines/immunology , Influenza, Human/immunology , T Follicular Helper Cells/immunology , Animals , Antibodies, Viral/immunology , Antibody Formation/immunology , Antigens , B-Lymphocytes/immunology , CD4-Positive T-Lymphocytes/immunology , CD4-Positive T-Lymphocytes/metabolism , Female , Germinal Center/immunology , Humans , Male , Mice , Mice, Inbred BALB C , Mice, Inbred C57BL , T Follicular Helper Cells/metabolism , T-Lymphocytes, Helper-Inducer/immunology , Vaccines, Attenuated/immunology
9.
Proc Natl Acad Sci U S A ; 119(4)2022 01 25.
Article in English | MEDLINE | ID: mdl-35042819

ABSTRACT

Inspired by the intriguing adaptivity of natural life, such as squids and flowers, we propose a series of dynamic and responsive multifunctional devices based on multiscale structural design, which contain metal nanocoating layers overlaid with other micro-/nanoscale soft or rigid layers. Since the optical/photothermal properties of a metal nanocoating are thickness dependent, metal nanocoatings with different thicknesses were chosen to integrate with other structural design elements to achieve dynamic multistimuli responses. The resultant devices demonstrate 1) strain-regulated cracked and/or wrinkled topography with tunable light-scattering properties, 2) moisture/photothermal-responsive structural color coupled with wrinkled surface, and 3) mechanically controllable light-shielding properties attributed to the strain-dependent crack width of the nanocoating. These devices can adapt external stimuli, such as mechanical strain, moisture, light, and/or heat, into corresponding changes of optical signals, such as transparency, reflectance, and/or coloration. Therefore, these devices can be applied as multistimuli-responsive encryption devices, smart windows, moisture/photothermal-responsive dynamic optics, and smartphone app-assisted pressure-mapping sensors. All the devices exhibit high reversibility and rapid responsiveness. Thus, this hybrid system containing ultrathin metal nanocoatings holds a unique design flexibility and adaptivity and is promising for developing next-generation multifunctional devices with widespread application.

10.
Biophys J ; 123(2): 118-133, 2024 Jan 16.
Article in English | MEDLINE | ID: mdl-38006207

ABSTRACT

Local perturbations to DNA base-pairing stability from lesions and chemical modifications can alter the stability and dynamics of an entire oligonucleotide. End effects may cause the position of a disruption within a short duplex to influence duplex stability and structural dynamics, yet this aspect of nucleic acid modifications is often overlooked. We investigate how the position of an abasic site (AP site) impacts the stability and dynamics of short DNA duplexes. Using a combination of steady-state and time-resolved spectroscopy and molecular dynamics simulations, we unravel an interplay between AP-site position and nucleobase sequence that controls energetic and dynamic disruption to the duplex. The duplex is disrupted into two segments by an entropic barrier for base-pairing on each side of the AP site. The barrier induces fraying of the short segment when an AP site is near the termini. Shifting the AP site inward promotes a transition from short-segment fraying to fully encompassing the barrier into the thermodynamics of hybridization, leading to further destabilization of the duplex. Nucleobase sequence determines the length scale for this transition by tuning the barrier height and base-pair stability of the short segment, and certain sequences enable out-of-register base-pairing to minimize the barrier height.


Subject(s)
DNA , Nucleic Acid Conformation , Base Pairing , Thermodynamics , DNA/genetics , DNA/chemistry , Entropy
11.
Lancet ; 402 Suppl 1: S54, 2023 Nov.
Article in English | MEDLINE | ID: mdl-37997097

ABSTRACT

BACKGROUND: Polygenic Risk Scores (PRSs) have been proposed as a mechanism for risk-stratification of screening, increasing efficiency and enabling extension of existing programmes to improve survival in our aging population. We sought to model the impact of three hypothetical programmes of annual breast cancer screening in women aged 40-49 years: screening the PRS-defined high-risk quintile, screening the oldest quintile, and screening the full population. METHODS: In this UK-based modelling study, we used the published estimate of the area under the curve (AUC) of a currently available breast cancer PRS (0·64) to calculate the proportion of cancers captured by the PRS-defined high-risk quintile. We used population size estimates from the Office for National Statistics alongside age-stratified incidence rates of breast cancer, and age or stage-specific survival data from the National Cancer Registry, to build our model. We used stage-specific route-to-diagnosis data to reassign stage-specific survival for screen-detected cancers. Ethics approval was not required. FINDINGS: The PRS-defined high-risk quintile, oldest quintile, and full population capture 37% (n=2811), 29% (n=2198), and 100% (n=7533) of breast cancers occurring in women aged 40-49 each year. Annual screening of each group using digital mammography (sensitivity 70%, specificity 92%) would identify 1968, 1538, and 5273 breast cancers per year, respectively. This corresponds to an improvement in survival of 1·4% (102 deaths averted), 1·1% (80 deaths averted) and 3·6% (274 deaths averted) compared with baseline (no screening). Full population screening would require 4 369 703 mammograms and 354 246 confirmatory tests (breast biopsies) every year, while screening the oldest quintile would require 937 850 mammograms and 76 390 biopsies. Screening the PRS-defined high-risk quintile would require 873 941 mammograms and 71 658 biopsies, in addition to a PRS for all women in the age group (4 369 703). INTERPRETATION: Under favourable assumptions, stratifying screening by PRS rather than age results in modest gains in survival but increases overdiagnoses, logistical complexity, and economic costs. Our study is limited by our modelling parameters (anticipated to maximise survival estimates), including complete uptake of PRS profiling and cancer screening, no interval cancers, and application of screening tools superior to those currently available in the UK. Only with randomised controlled trials, can the uptake, clinical impact, costs, and harms of PRS-stratified screening be definitively assessed. FUNDING: The Wellcome Trust.


Subject(s)
Breast Neoplasms , Female , Humans , Aged , Breast Neoplasms/diagnosis , Breast Neoplasms/epidemiology , Breast Neoplasms/genetics , Early Detection of Cancer/methods , Mammography/methods , Breast , Risk Factors , Mass Screening/methods , Risk Assessment
12.
Am J Gastroenterol ; 2024 Apr 22.
Article in English | MEDLINE | ID: mdl-38501671

ABSTRACT

INTRODUCTION: The 2021 American Association for the Study of Liver Disease (AASLD) Practice Guidance recommends albumin infusion when removing ≥5 L of ascites to prevent post-paracentesis circulatory dysfunction. However, the optimal criteria and scenarios for initiating albumin infusion subsequent to therapeutic paracentesis (TP) have been subject to limited scientific inquiry. METHODS: We conducted a retrospective cohort study at a US academic healthcare center. Participants received elective, outpatient TP between July 2019 and December 2022. Patients with spontaneous bacterial peritonitis, post-TP clinical adjustments, and/or hospitalization were excluded. The institution strictly followed the AASLD Guidance. We used a sharp regression discontinuity (RD) design to estimate the effect of albumin infusion at the AASLD Guidance-recommended cutoff of 5 L on serum creatinine and sodium trajectory after TP. RESULTS: Over the study period, 1,457 elective TPs were performed on 235 unique patients. Albumin infusion at the threshold of 5 L of ascites removal reduced serum creatinine levels by 0.046 mg/dL/d (95% confidence interval 0.003-0.116, P = 0.037) and increased serum sodium levels by 0.35 mEq/L/d (95% confidence interval 0.15-0.55, P = 0.001) compared with those who did not receive albumin infusion. The RD plots indicated worsened serum creatine/sodium levels after draining 3 L of fluid, approaching levels similar to or worse than with albumin infusion at 5 L or more. DISCUSSION: Our RD models supported the 2021 AASLD Guidance with robust estimation of causal effect sizes at the cutoff level of 5 L. Nevertheless, the findings also highlight the need to further evaluate the efficacy of albumin infusion in patients who undergo elective TP and have 3-5 L of ascites removed.

13.
Am J Gastroenterol ; 2024 Sep 06.
Article in English | MEDLINE | ID: mdl-39248599

ABSTRACT

OBJECTIVES: Obstetric anal sphincter injury (OASI) is associated with serious morbidity and reduced quality of life. The role of anorectal manometry (ARM) to guide treatment is unclear. We aimed to define the role of ARM and symptom assessment post OASI in predicting anal incontinence at long-term follow-up. METHODS: Prospective evaluation of 205 consecutive post-OASI women who underwent baseline ARM and symptom assessment in a tertiary setting was undertaken. 99 were available for long term follow-up (median 6.6 years). Associations between post-OASI ARM testing and short- and long- term anal incontinence were examined in addition to clinical and obstetric factors. RESULTS: 4th degree tears and lower anal resting and squeeze pressures were associated with short-term anal incontinence. Females with anal incontinence at baseline, and females with lower anal resting pressure, were more likely to suffer from long-term fecal incontinence (FI). A best-fit cut-off value of 59 mmHg for baseline anal resting pressure predicted long-term FI, and none of the short-term asymptomatic females with an anal resting pressure of >59mmHg reported FI at long-term follow-up. CONCLUSIONS: Symptoms of anal incontinence and ARM in patients post OASI are both useful to predict subsequent long-term FI with a best-fit cut-off of 59mmHg for anal resting pressure. This provides rationale for routine ARM and accurate symptom assessment in all patients after OASI, to identify high risk groups to follow and treat, and it may assist decision-making regarding mode of subsequent obstetric deliveries.

14.
Am J Gastroenterol ; 2024 Apr 24.
Article in English | MEDLINE | ID: mdl-38483301

ABSTRACT

INTRODUCTION: Disorders of gut-brain interaction (DGBIs) may originate in childhood. There are currently limited data on persistence of DGBI into adulthood and risk factors for persistence. Furthermore, there are no data on this question from general practice, where the majority of DGBIs are diagnosed and managed. This study documents the proportion of childhood-diagnosed DGBIs that persisted into adulthood and what factors were associated with persistence. METHODS: General practice records were obtained for more than 60,000 patients whose medical record spanned both childhood and adulthood years. Patients with diagnosed organic gastrointestinal disorder were excluded. Medical records were also interrogated for potential risk factors. RESULTS: Eleven percent of patients with irritable bowel syndrome (IBS) and 20% of patients with functional dyspepsia (FD) diagnosed in childhood had repeat diagnoses of the same condition in adulthood. Female sex (odds ratio [OR] 2.02) was associated with persistence for IBS, while a childhood diagnosis of gastritis (OR 0.46) was risk-protective. Childhood non-steroidal anti-inflammatory drug use (OR 1.31, 95% confidence interval [CI] 1.09-1.56) was a risk factor for persistence in IBS. For FD, a childhood diagnosis of asthma (OR 1.30, 95% CI 1.00-1.70) was a risk factor, as was anxiety for both IBS (OR 1.24, 95% CI 1.00-1.54) and FD (OR 1.48 95% CI 1.11-1.97) with a similar finding for depression for IBS (OR 1.34, 95% CI 1.11-1.62) and FD (OR 1.88 95% CI 1.47-2.42). DISCUSSION: Childhood DGBIs persist into adulthood in 10%-20% of patients, suggesting that management monitoring should continue into adulthood. Those diagnosed with anxiety or mood disorders in childhood should receive particular attention, and prescription of non-steroidal anti-inflammatory drugs in children should be made judiciously.

15.
Breast Cancer Res Treat ; 206(2): 295-305, 2024 Jul.
Article in English | MEDLINE | ID: mdl-38653906

ABSTRACT

PURPOSE: Mammographic density phenotypes, adjusted for age and body mass index (BMI), are strong predictors of breast cancer risk. BMI is associated with mammographic density measures, but the role of circulating sex hormone concentrations is less clear. We investigated the relationship between BMI, circulating sex hormone concentrations, and mammographic density phenotypes using Mendelian randomization (MR). METHODS: We applied two-sample MR approaches to assess the association between genetically predicted circulating concentrations of sex hormones [estradiol, testosterone, sex hormone-binding globulin (SHBG)], BMI, and mammographic density phenotypes (dense and non-dense area). We created instrumental variables from large European ancestry-based genome-wide association studies and applied estimates to mammographic density phenotypes in up to 14,000 women of European ancestry. We performed analyses overall and by menopausal status. RESULTS: Genetically predicted BMI was positively associated with non-dense area (IVW: ß = 1.79; 95% CI = 1.58, 2.00; p = 9.57 × 10-63) and inversely associated with dense area (IVW: ß = - 0.37; 95% CI = - 0.51,- 0.23; p = 4.7 × 10-7). We observed weak evidence for an association of circulating sex hormone concentrations with mammographic density phenotypes, specifically inverse associations between genetically predicted testosterone concentration and dense area (ß = - 0.22; 95% CI = - 0.38, - 0.053; p = 0.009) and between genetically predicted estradiol concentration and non-dense area (ß = - 3.32; 95% CI = - 5.83, - 0.82; p = 0.009), although results were not consistent across a range of MR approaches. CONCLUSION: Our findings support a positive causal association between BMI and mammographic non-dense area and an inverse association between BMI and dense area. Evidence was weaker and inconsistent for a causal effect of circulating sex hormone concentrations on mammographic density phenotypes. Based on our findings, associations between circulating sex hormone concentrations and mammographic density phenotypes are weak at best.


Subject(s)
Body Mass Index , Breast Density , Breast Neoplasms , Genome-Wide Association Study , Gonadal Steroid Hormones , Mendelian Randomization Analysis , Humans , Female , Breast Neoplasms/genetics , Breast Neoplasms/blood , Breast Neoplasms/diagnostic imaging , Gonadal Steroid Hormones/blood , Sex Hormone-Binding Globulin/analysis , Sex Hormone-Binding Globulin/metabolism , Sex Hormone-Binding Globulin/genetics , Middle Aged , Polymorphism, Single Nucleotide , Mammography , Estradiol/blood , Testosterone/blood , Phenotype
16.
Clin Exp Allergy ; 54(1): 21-33, 2024 01.
Article in English | MEDLINE | ID: mdl-38177093

ABSTRACT

BACKGROUND: Vancomycin, a glycopeptide antibiotic used for Gram-positive bacterial infections, has been linked with drug reaction with eosinophilia and systemic symptoms (DRESS) in HLA-A*32:01-expressing individuals. This is associated with activation of T lymphocytes, for which glycolysis has been isolated as a fuel pathway following antigenic stimulation. However, the metabolic processes that underpin drug-reactive T-cell activation are currently undefined and may shed light on the energetic conditions needed for the elicitation of drug hypersensitivity or tolerogenic pathways. Here, we sought to characterise the immunological and metabolic pathways involved in drug-specific T-cell activation within the context of DRESS pathogenesis using vancomycin as model compound and drug-reactive T-cell clones (TCCs) generated from healthy donors and vancomycin-hypersensitive patients. METHODS: CD4+ and CD8+ vancomycin-responsive TCCs were generated by serial dilution. The Seahorse XFe96 Analyzer was used to measure the extracellular acidification rate (ECAR) as an indicator of glycolytic function. Additionally, T-cell proliferation and cytokine release (IFN-γ) assay were utilised to correlate the bioenergetic characteristics of T-cell activation with in vitro assays. RESULTS: Model T-cell stimulants induced non-specific T-cell activation, characterised by immediate augmentation of ECAR and rate of ATP production (JATPglyc). There was a dose-dependent and drug-specific glycolytic shift when vancomycin-reactive TCCs were exposed to the drug. Vancomycin-reactive TCCs did not exhibit T-cell cross-reactivity with structurally similar compounds within proliferative and cytokine readouts. However, cross-reactivity was observed when analysing energetic responses; TCCs with prior specificity for vancomycin were also found to exhibit glycolytic switching after exposure to teicoplanin. Glycolytic activation of TCC was HLA restricted, as exposure to HLA blockade attenuated the glycolytic induction. CONCLUSION: These studies describe the glycolytic shift of CD4+ and CD8+ T cells following vancomycin exposure. Since similar glycolytic switching is observed with teicoplanin, which did not activate T cells, it is possible the master switch for T-cell activation is located upstream of metabolic signalling.


Subject(s)
Teicoplanin , Vancomycin , Humans , Vancomycin/adverse effects , CD8-Positive T-Lymphocytes , Lymphocyte Activation , Cytokines , Glycolysis
17.
Electrophoresis ; 45(15-16): 1389-1397, 2024 Aug.
Article in English | MEDLINE | ID: mdl-38415778

ABSTRACT

The work describes the use of SYBR Gold to improve the detection sensitivity of plasmid DNA topoisomers by capillary gel electrophoresis with laser induced fluorescence in an uncoated capillary. The impact of different dyes, including ethidium bromide, SYBR Green and SYBR Gold, was compared based on detection and separation of DNA plasmid topoisomers. Use of SYBR Gold enabled improvement of detection sensitivity by 15-fold while maintaining good separation resolution of the different topoisomers. The baseline dropped with the use SYBR Gold but was overcome by the employment of a capillary with longer ineffective length (40 vs. 20 cm). Separation resolution and reproducibility were impacted by the concentration of SYBR Gold and hydroxypropyl methylcellulose. With the use of a short capillary (10 cm effective length and 50 cm total length), fast separations of supercoiled, linear, open circular, and other isoforms were accomplished within 8 min. Appropriate capillary cleaning with 0.1 M sodium hydroxide/0.1 M hydrochloric acid and capillary storage with 0.1 M hydrochloric acid ensured good separation reproducibility of 217 runs during an extended period of use.


Subject(s)
Electrophoresis, Capillary , Plasmids , Electrophoresis, Capillary/methods , Reproducibility of Results , DNA/analysis , DNA/chemistry , DNA/isolation & purification , Lasers , Organic Chemicals/chemistry , Sensitivity and Specificity , Fluorescent Dyes/chemistry , Ethidium/chemistry
18.
Br J Dermatol ; 2024 Jul 24.
Article in English | MEDLINE | ID: mdl-39044673

ABSTRACT

BACKGROUND: The main conventional systemic atopic dermatitis (AD) treatments are methotrexate (MTX) and ciclosporin (CyA). Dupilumab was the first novel systemic agent to enter routine clinical practice. There are no head-to-head randomised controlled trials or real-world studies comparing these agents directly. Network meta-analyses provide indirect comparative efficacy and safety data and have shown strong evidence for dupilumab and CyA. OBJECTIVES: The aim of this study was to compare the real-world clinical effectiveness and safety of CyA, dupilumab and MTX in AD. METHODS: We compared the effectiveness and safety of these systemic agents in a prospective observational cohort study of adult and paediatric patients recruited into the UK-Irish Atopic eczema Systemic TherApy Register (A-STAR). Treatment effectiveness measures included Eczema Area and Severity Index (EASI), Patient-Oriented Eczema Measure (POEM), Peak Pruritus Numerical Rating Scale (PP-NRS), Dermatology Life Quality Index (DLQI) and children's DLQI (cDLQI). Minimum duration of treatment was 28 days and follow-up was 12 months. Adjusted Cox-regression was used to compare the hazards of achieving EASI-50, EASI-75 and EASI-90 over time, and linear mixed-effects models were used to estimate changes in efficacy scores. Treatment safety was assessed by examining adverse events (AEs) at follow-up visits. RESULTS: 488 patients (n=311 adults and n=177 children/adolescents) on dupilumab (n=282), methotrexate (n=149), or CyA (n=57) were included. CyA and MTX were primarily used first line, while dupilumab was mainly a second line systemic as per UK National Institute of Clinical and Care Excellence (NICE) recommendations. EASI-50, EASI-75 and EASI-90 were achieved more rapidly in the dupilumab and CyA groups compared to MTX. After adjustment for previous severity, the reduction in EASI, POEM, PP-NRS and DLQI was greater for patients treated with dupilumab compared to MTX. In severe patients the reduction in EASI, POEM, and PP-NRS was even greater with CyA. The incidence of AEs was similar across groups (734, 654 and 594 per 10,000 person-month on CyA, dupilumab and MTX respectively). CONCLUSIONS: This real-world comparison of CyA, dupilumab and MTX in AD suggests that dupilumab is consistently more effective than MTX and that CyA is most effective in very severe disease within one follow-up year.

19.
Br J Dermatol ; 2024 Sep 05.
Article in English | MEDLINE | ID: mdl-39236226

ABSTRACT

BACKGROUND: Atopic dermatitis (AD) is the most common inflammatory skin condition which affects all ages. New therapies, including the monoclonal antibody therapy dupilumab, offer excellent efficacy. However, in clinical trials, and emphasised in real-world observations, the unexpected increased frequency of ocular adverse effects became apparent. The effectiveness of dupilumab and the unpredictability of ocular adverse effects mean that clinicians need guidance on counselling patients prior to treatment and on managing them if they arise. OBJECTIVES: The British Association of Dermatologists (BAD) and Royal College of Ophthalmologists collaborated on this consensus guidance on managing dupilumab-related ocular surface disorders (DROSD). METHODS: A multidisciplinary group was formed of adult and paediatric dermatologists and ophthalmologists with DROSD expertise, patient representation, and BAD Clinical Standards Unit. A literature search was conducted, and the results reviewed. All recommendations were reviewed, discussed and voted on. RESULTS: The recommendations pertain to dermatology and ophthalmology management, and apply to all ages, unless otherwise stated. Importantly, initiation of dupilumab for AD should not be delayed for most eye disorders except acute new problems, e.g. infections, or potentially severe conditions, e.g. a history of corneal transplant (ophthalmology advice should be sought first). There is insufficient evidence to recommend lubricant drops prophylactically. Dermatologists should assess eye complaints to diagnose DROSD; a severity grading system is provided. DROSD management differs slightly in those aged <7 years as ocular complications may affect neuro-ocular development; therefore, irrespective of DROSD severity, this population should be referred for ophthalmology advice. In those aged ≥7 years, dermatologists should feel confident to trial treatment and reserve ophthalmology advice for severe or non-responding cases. Discussion about dupilumab withdrawal should be prompted by a significant impact on quality of life, threat to sight, or other complications. CONCLUSIONS: Although dupilumab is a highly effective agent for treating AD, the risk of ocular adverse effects should not inhibit clinicians or patients from using it, but clinicians should be aware of them. If a patient develops DROSD, there are clear pathways to assess severity and offer initial management; where ineffective, dermatologists should assess the urgency and seek advice from or initiate referral to ophthalmology. While the evidence reviewed for these guidelines reflects the extensive literature on dupilumab, we believe our advice has relevance for ocular surface disorders in atopic dermatitis (AD) patients treated with tralokinumab and lebrikizumab.

20.
J Clin Gastroenterol ; 58(1): 57-63, 2024 01 01.
Article in English | MEDLINE | ID: mdl-36730549

ABSTRACT

GOALS: To evaluate the usefulness of a 2-week patient-completed bowel habit and symptom diary as a screening tool for disordered rectoanal coordination (DRC). BACKGROUND: DRC is an important subgroup of chronic constipation that benefits from biofeedback treatment. Diagnosis of DRC requires a dyssynergic pattern (DP) of attempted defecation in high-resolution anorectal manometry (HRAM) and at least 1 other positive standardized examination, such as the balloon expulsion test or defecography. However, HRAM is generally limited to tertiary gastroenterology centres and finding tools for selecting patients for referral for further investigations would be of clinical value. STUDY: Retrospective data from HRAM and a 2-week patient-completed bowel habit and symptom diary from 99 chronically constipated patients were analyzed. RESULTS: Fifty-seven percent of the patients had a DP pattern during HRAM. In the DP group, 76% of bowel movements with loose or normal stool resulted in a sense of incomplete evacuation compared with 55% of the non-DP group ( P =0.004). Straining and sensation of incomplete evacuation with the loose stool were significantly more common in the DP group ( P =0.032). Hard stool was a discriminator for non-DP ( P =0.044). Multiple logistic regression including incomplete evacuation and normal stool predicted DP with a sensitivity of 82% and a specificity of 50%. CONCLUSIONS: The sensation of incomplete evacuation with loose or normal stool could be a potential discriminator in favor of DP in chronically constipated patients. The bowel habit and symptom diary may be a useful tool for stratifying constipated patients for further investigation of suspected DRC.


Subject(s)
Constipation , Defecation , Humans , Retrospective Studies , Manometry/methods , Constipation/diagnosis , Constipation/therapy , Biofeedback, Psychology/methods , Anal Canal
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