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1.
Cereb Cortex ; 33(8): 4334-4349, 2023 04 04.
Artículo en Inglés | MEDLINE | ID: mdl-36066407

RESUMEN

Accumulating evidence indicates that the adult brain is capable of significant structural change following damage-a capacity once thought to be largely limited to developing brains. To date, most existing research on adult plasticity has focused on how exteroceptive sensorimotor networks compensate for damage to preserve function. Interoceptive networks-those that represent and process sensory information about the body's internal state-are now recognized to be critical for a wide range of physiological and psychological functions from basic energy regulation to maintaining a sense of self, but the extent to which these networks remain plastic in adulthood has not been established. In this report, we used detailed histological analyses to pinpoint precise changes to gray matter volume in the interoceptive-allostatic network in adult rhesus monkeys (Macaca mulatta) who received neurotoxic lesions of the anterior cingulate cortex (ACC) and neurologically intact control monkeys. Relative to controls, monkeys with ACC lesions had significant and selective unilateral expansion of the ventral anterior insula and significant relative bilateral expansion of the lateral nucleus of the amygdala. This work demonstrates the capacity for neuroplasticity in the interoceptive-allostatic network which, given that changes included expansion rather than atrophy, is likely to represent an adaptive response following damage.


Asunto(s)
Corteza Cerebral , Giro del Cíngulo , Animales , Giro del Cíngulo/fisiología , Corteza Cerebral/fisiología , Encéfalo/fisiología , Mapeo Encefálico , Macaca mulatta
2.
Clin Infect Dis ; 74(7): 1208-1219, 2022 04 09.
Artículo en Inglés | MEDLINE | ID: mdl-34216472

RESUMEN

BACKGROUND: Natural and vaccine-induced immunity will play a key role in controlling the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) pandemic. SARS-CoV-2 variants have the potential to evade natural and vaccine-induced immunity. METHODS: In a longitudinal cohort study of healthcare workers (HCWs) in Oxfordshire, United Kingdom, we investigated the protection from symptomatic and asymptomatic polymerase chain reaction (PCR)-confirmed SARS-CoV-2 infection conferred by vaccination (Pfizer-BioNTech BNT162b2, Oxford-AstraZeneca ChAdOx1 nCOV-19) and prior infection (determined using anti-spike antibody status), using Poisson regression adjusted for age, sex, temporal changes in incidence and role. We estimated protection conferred after 1 versus 2 vaccinations and from infections with the B.1.1.7 variant identified using whole genome sequencing. RESULTS: In total, 13 109 HCWs participated; 8285 received the Pfizer-BioNTech vaccine (1407 two doses), and 2738 the Oxford-AstraZeneca vaccine (49 two doses). Compared to unvaccinated seronegative HCWs, natural immunity and 2 vaccination doses provided similar protection against symptomatic infection: no HCW vaccinated twice had symptomatic infection, and incidence was 98% lower in seropositive HCWs (adjusted incidence rate ratio 0.02 [95% confidence interval {CI} < .01-.18]). Two vaccine doses or seropositivity reduced the incidence of any PCR-positive result with or without symptoms by 90% (0.10 [95% CI .02-.38]) and 85% (0.15 [95% CI .08-.26]), respectively. Single-dose vaccination reduced the incidence of symptomatic infection by 67% (0.33 [95% CI .21-.52]) and any PCR-positive result by 64% (0.36 [95% CI .26-.50]). There was no evidence of differences in immunity induced by natural infection and vaccination for infections with S-gene target failure and B.1.1.7. CONCLUSIONS: Natural infection resulting in detectable anti-spike antibodies and 2 vaccine doses both provide robust protection against SARS-CoV-2 infection, including against the B.1.1.7 variant.


Asunto(s)
COVID-19 , SARS-CoV-2 , Vacuna BNT162 , COVID-19/epidemiología , COVID-19/prevención & control , Vacunas contra la COVID-19 , ChAdOx1 nCoV-19 , Estudios de Cohortes , Personal de Salud , Humanos , Inmunoglobulinas , Incidencia , Estudios Longitudinales , Vacunación
3.
Development ; 146(20)2019 10 24.
Artículo en Inglés | MEDLINE | ID: mdl-31575649

RESUMEN

Massive, coordinated cellular changes accompany the transition of central nervous system (CNS) progenitors from forebrain neurectodermal cells to specified neuroepithelial cells. We have previously found that MYC regulates the changing ribosomal and proteostatic landscapes in mouse forebrain precursors at embryonic days E8.5 and E10.5 (before and after neural tube closure; NTC) (Chau et al., 2018). Here, we demonstrate parallel coordinated transcriptional changes in metabolic machinery during this same stage of forebrain specification. Progenitors showed striking mitochondrial structural changes transitioning from glycolytic cristae at E8.5, to more traditional mitochondria at E10.5. Accordingly, glucose use shifted in progenitors such that E8.5 progenitors relied on glycolysis, and after NTC increasingly used oxidative phosphorylation. This metabolic shift was matched by changes in surrounding amniotic and cerebrospinal fluid proteomes. Importantly, these mitochondrial morphological shifts depend on MYC downregulation. Together, our findings demonstrate that metabolic shifting accompanies dynamic organelle and proteostatic remodeling of progenitor cells during the earliest stages of forebrain development.


Asunto(s)
Mitocondrias/metabolismo , Proteoma/metabolismo , Animales , Sistema Nervioso Central/metabolismo , Epitelio/metabolismo , Femenino , Glucólisis , Immunoblotting , Masculino , Ratones , Ratones Mutantes , Microscopía Electrónica de Transmisión , Células Neuroepiteliales/citología , Células Neuroepiteliales/metabolismo , Prosencéfalo/citología , Prosencéfalo/metabolismo , RNA-Seq , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa
4.
Mol Psychiatry ; 26(12): 7560-7580, 2021 12.
Artículo en Inglés | MEDLINE | ID: mdl-34433918

RESUMEN

Reciprocal deletion and duplication of the 16p11.2 region is the most common copy number variation (CNV) associated with autism spectrum disorders. We generated cortical organoids from skin fibroblasts of patients with 16p11.2 CNV to investigate impacted neurodevelopmental processes. We show that organoid size recapitulates macrocephaly and microcephaly phenotypes observed in the patients with 16p11.2 deletions and duplications. The CNV dosage affects neuronal maturation, proliferation, and synapse number, in addition to its effect on organoid size. We demonstrate that 16p11.2 CNV alters the ratio of neurons to neural progenitors in organoids during early neurogenesis, with a significant excess of neurons and depletion of neural progenitors observed in deletions. Transcriptomic and proteomic profiling revealed multiple pathways dysregulated by the 16p11.2 CNV, including neuron migration, actin cytoskeleton, ion channel activity, synaptic-related functions, and Wnt signaling. The level of the active form of small GTPase RhoA was increased in both, deletions and duplications. Inhibition of RhoA activity rescued migration deficits, but not neurite outgrowth. This study provides insights into potential neurobiological mechanisms behind the 16p11.2 CNV during neocortical development.


Asunto(s)
Trastorno del Espectro Autista , Trastorno Autístico , Trastorno del Espectro Autista/genética , Trastorno Autístico/genética , Encéfalo , Deleción Cromosómica , Cromosomas Humanos Par 16/genética , Variaciones en el Número de Copia de ADN/genética , Humanos , Neurogénesis/genética , Organoides , Proteómica
5.
Mol Psychiatry ; 26(7): 3586-3613, 2021 07.
Artículo en Inglés | MEDLINE | ID: mdl-33727673

RESUMEN

E3-ubiquitin ligase Cullin3 (Cul3) is a high confidence risk gene for autism spectrum disorder (ASD) and developmental delay (DD). To investigate how Cul3 mutations impact brain development, we generated a haploinsufficient Cul3 mouse model using CRISPR/Cas9 genome engineering. Cul3 mutant mice exhibited social and cognitive deficits and hyperactive behavior. Brain MRI found decreased volume of cortical regions and changes in many other brain regions of Cul3 mutant mice starting from early postnatal development. Spatiotemporal transcriptomic and proteomic profiling of embryonic, early postnatal and adult brain implicated neurogenesis and cytoskeletal defects as key drivers of Cul3 functional impact. Specifically, dendritic growth, filamentous actin puncta, and spontaneous network activity were reduced in Cul3 mutant mice. Inhibition of small GTPase RhoA, a molecular substrate of Cul3 ligase, rescued dendrite length and network activity phenotypes. Our study identified defects in neuronal cytoskeleton and Rho signaling as the primary targets of Cul3 mutation during brain development.


Asunto(s)
Trastorno del Espectro Autista , Trastorno Autístico , Animales , Trastorno del Espectro Autista/genética , Proteínas Cullin/genética , Citoesqueleto , Células Germinativas , Haploinsuficiencia/genética , Ratones , Neurogénesis/genética , Proteómica
6.
Clin Infect Dis ; 73(12): 2276-2282, 2021 12 16.
Artículo en Inglés | MEDLINE | ID: mdl-33411882

RESUMEN

BACKGROUND: The incidence of bloodstream infections (BSIs) caused by Escherichia coli and Klebsiella pneumoniae is increasing, with substantial associated morbidity, mortality, and antimicrobial resistance. Unbiased serotyping studies to guide vaccine target selection are limited. METHODS: We conducted unselected, population-level genomic surveillance of bloodstream E. coli and Klebsiella pneumoniae isolates from 2008 to 2018 in Oxfordshire, United Kingdom. We supplemented this with an analysis of publicly available global sequencing data (n = 3678). RESULTS: We sequenced 3478 E. coli isolates (3278 passed quality control) and 556 K. pneumoniae isolates (535 [K-antigen] and 549 [O-antigen] passed quality control). The 4 most common E. coli O-antigens (O1/O2/O6/O25) were identified in 1499/3278 isolates; the incidence of these O-types increased over time (incidence rate ratio per year [IRRy] = 1.14, 95% confidence interval [CI]: 1.11-1.16). These O-types accounted for 616/1434 multidrug-resistant (MDR) and 173/256 extended-spectrum beta-lactamase (ESBL)-resistant isolates in Oxfordshire but only 19/90 carbapenem-resistant isolates across all studies. For Klebsiella pneumoniae, the most common O-antigens (O2v2/O1v1/O3b/O1v2) accounted for 410/549 isolates; the incidence of BSIs caused by these also increased annually (IRRy = 1.09; 95% CI: 1.05-1.12). These O-types accounted for 122/148 MDR and 106/123 ESBL isolates in Oxfordshire and 557/734 carbapenem-resistant isolates across all studies. Conversely we observed substantial capsular antigen diversity. Analysis of 3678 isolates from global studies demonstrated the generalizability of these findings. For E. coli, based on serotyping, the ExPEC4V and ExPEC10V vaccines under investigation would cover 46% and 72% of Oxfordshire isolates respectively, and 47% and 71% of MDR isolates. CONCLUSIONS: O-antigen targeted vaccines may be useful in reducing the morbidity, mortality, and antimicrobial resistance associated with E. coli and K. pneumoniae BSIs.


Asunto(s)
Infecciones por Escherichia coli , Infecciones por Klebsiella , Antibacterianos/farmacología , Farmacorresistencia Bacteriana Múltiple/genética , Escherichia coli , Infecciones por Escherichia coli/epidemiología , Genómica , Humanos , Infecciones por Klebsiella/epidemiología , Klebsiella pneumoniae , Pruebas de Sensibilidad Microbiana , Serogrupo , Desarrollo de Vacunas , beta-Lactamasas/genética
7.
Breast Cancer Res ; 22(1): 89, 2020 08 14.
Artículo en Inglés | MEDLINE | ID: mdl-32795346

RESUMEN

BACKGROUND: Combined targeting of CDK4/6 and ER is now the standard of care for patients with advanced ER+/HER2- breast cancer. However, acquired resistance to these therapies frequently leads to disease progression. As such, it is critical to identify the mechanisms by which resistance to CDK4/6-based therapies is acquired and also identify therapeutic strategies to overcome resistance. METHODS: In this study, we developed and characterized multiple in vitro and in vivo models of acquired resistance to CDK4/6-based therapies. Resistant models were screened by reverse phase protein array (RPPA) for cell signaling changes that are activated in resistance. RESULTS: We show that either a direct loss of Rb or loss of dependence on Rb signaling confers cross-resistance to inhibitors of CDK4/6, while PI3K/mTOR signaling remains activated. Treatment with the p110α-selective PI3K inhibitor, alpelisib (BYL719), completely blocked the progression of acquired CDK4/6 inhibitor-resistant xenografts in the absence of continued CDK4/6 inhibitor treatment in models of both PIK3CA mutant and wild-type ER+/HER2- breast cancer. Triple combination therapy against PI3K:CDK4/6:ER prevented and/or delayed the onset of resistance in treatment-naive ER+/HER2- breast cancer models. CONCLUSIONS: These data support the clinical investigation of p110α-selective inhibitors of PI3K, such as alpelisib, in patients with ER+/HER2- breast cancer who have progressed on CDK4/6:ER-based therapies. Our data also support the investigation of PI3K:CDK4/6:ER triple combination therapy to prevent the onset of resistance to the combination of endocrine therapy plus CDK4/6 inhibition.


Asunto(s)
Neoplasias de la Mama/tratamiento farmacológico , Quinasa 4 Dependiente de la Ciclina/antagonistas & inhibidores , Quinasa 6 Dependiente de la Ciclina/antagonistas & inhibidores , Resistencia a Antineoplásicos , Receptor alfa de Estrógeno/antagonistas & inhibidores , Fosfatidilinositol 3-Quinasas/química , Serina-Treonina Quinasas TOR/antagonistas & inhibidores , Animales , Neoplasias de la Mama/metabolismo , Neoplasias de la Mama/patología , Línea Celular Tumoral , Evaluación Preclínica de Medicamentos , Femenino , Humanos , Ratones Desnudos , Terapia Molecular Dirigida , Fosfatidilinositol 3-Quinasas/metabolismo , Embarazo , Inhibidores de Proteínas Quinasas/farmacología , Transducción de Señal , Serina-Treonina Quinasas TOR/metabolismo , Ensayos Antitumor por Modelo de Xenoinjerto
8.
Euro Surveill ; 25(42)2020 10.
Artículo en Inglés | MEDLINE | ID: mdl-33094717

RESUMEN

SARS-CoV-2 IgG screening of 1,000 antenatal serum samples in the Oxford area, United Kingdom, between 14 April and 15 June 2020, yielded a 5.3% seroprevalence, mirroring contemporaneous regional data. Among the 53 positive samples, 39 showed in vitro neutralisation activity, correlating with IgG titre (Pearson's correlation p<0.0001). While SARS-CoV-2 seroprevalence in pregnancy cohorts could potentially inform population surveillance, clinical correlates of infection and immunity in pregnancy, and antenatal epidemiology evolution over time need further study.


Asunto(s)
Anticuerpos Neutralizantes/sangre , Anticuerpos Antivirales/sangre , Betacoronavirus/inmunología , Infecciones por Coronavirus/epidemiología , Inmunoglobulina G/sangre , Pandemias , Neumonía Viral/epidemiología , Vigilancia de la Población , Complicaciones Infecciosas del Embarazo/sangre , Primer Trimestre del Embarazo/sangre , Adolescente , Adulto , COVID-19 , Estudios de Cohortes , Infecciones por Coronavirus/sangre , Inglaterra/epidemiología , Ensayo de Inmunoadsorción Enzimática , Femenino , Humanos , Persona de Mediana Edad , Neumonía Viral/sangre , Embarazo , Diagnóstico Prenatal , Prevalencia , SARS-CoV-2 , Estudios Seroepidemiológicos , Método Simple Ciego , Adulto Joven
10.
Am J Pathol ; 188(6): 1334-1344, 2018 06.
Artículo en Inglés | MEDLINE | ID: mdl-29545198

RESUMEN

Choroid plexus tumors and ciliary body medulloepithelioma are predominantly pediatric neoplasms. Progress in understanding the pathogenesis of these tumors has been hindered by their rarity and lack of models that faithfully recapitulate the disease. Here, we find that endogenous Myc proto-oncogene protein is down-regulated in the forebrain neuroepithelium, whose neural plate border domains give rise to the anterior choroid plexus and ciliary body. To uncover the consequences of persistent Myc expression, MYC expression was forced in multipotent neural precursors (nestin-Cre:Myc), which produced fully penetrant models of choroid plexus carcinoma and ciliary body medulloepithelioma. Nestin-mediated MYC expression in the epithelial cells of choroid plexus leads to the regionalized formation of choroid plexus carcinoma in the posterior domain of the lateral ventricle choroid plexus and the fourth ventricle choroid plexus that is accompanied by loss of multiple cilia, up-regulation of protein biosynthetic machinery, and hydrocephalus. Parallel MYC expression in the ciliary body leads also to up-regulation of protein biosynthetic machinery. Additionally, Myc expression in human choroid plexus tumors increases with aggressiveness of disease. Collectively, our findings expose a select vulnerability of the neuroepithelial lineage to postnatal tumorigenesis and provide a new mouse model for investigating the pathogenesis of these rare pediatric neoplasms.


Asunto(s)
Carcinogénesis/patología , Neoplasias del Plexo Coroideo/patología , Cuerpo Ciliar/patología , Modelos Animales de Enfermedad , Neuronas/metabolismo , Proteínas Proto-Oncogénicas c-myc/metabolismo , Adolescente , Adulto , Animales , Carcinogénesis/genética , Carcinogénesis/metabolismo , Niño , Preescolar , Neoplasias del Plexo Coroideo/genética , Neoplasias del Plexo Coroideo/metabolismo , Cuerpo Ciliar/metabolismo , Femenino , Humanos , Lactante , Masculino , Ratones , Ratones Endogámicos C57BL , Ratones Transgénicos , Neuronas/patología , Proto-Oncogenes Mas , Proteínas Proto-Oncogénicas c-myc/genética , Adulto Joven
11.
Euro Surveill ; 23(27)2018 07.
Artículo en Inglés | MEDLINE | ID: mdl-29991383

RESUMEN

We describe a gonorrhoea case with combined high-level azithromycin resistance and ceftriaxone resistance. In February 2018, a heterosexual male was diagnosed with gonorrhoea in the United Kingdom following sexual intercourse with a locally resident female in Thailand and failed treatment with ceftriaxone plus doxycycline and subsequently spectinomycin. Resistance arose from two mechanisms combining for the first time in a genetic background similar to a commonly circulating strain. Urgent action is essential to prevent further spread.


Asunto(s)
Farmacorresistencia Bacteriana/efectos de los fármacos , Gonorrea/tratamiento farmacológico , Neisseria gonorrhoeae/efectos de los fármacos , Neisseria gonorrhoeae/aislamiento & purificación , Espectinomicina/uso terapéutico , Adulto , Antibacterianos/uso terapéutico , Azitromicina/farmacología , Ceftriaxona/farmacología , Doxiciclina/farmacología , Inglaterra , Gonorrea/diagnóstico , Humanos , Masculino , Pruebas de Sensibilidad Microbiana , Neisseria gonorrhoeae/genética , Análisis de Secuencia , Tailandia , Viaje , Insuficiencia del Tratamiento
13.
J Neurosci ; 35(12): 4903-16, 2015 Mar 25.
Artículo en Inglés | MEDLINE | ID: mdl-25810521

RESUMEN

A sheet of choroid plexus epithelial cells extends into each cerebral ventricle and secretes signaling factors into the CSF. To evaluate whether differences in the CSF proteome across ventricles arise, in part, from regional differences in choroid plexus gene expression, we defined the transcriptome of lateral ventricle (telencephalic) versus fourth ventricle (hindbrain) choroid plexus. We find that positional identities of mouse, macaque, and human choroid plexi derive from gene expression domains that parallel their axial tissues of origin. We then show that molecular heterogeneity between telencephalic and hindbrain choroid plexi contributes to region-specific, age-dependent protein secretion in vitro. Transcriptome analysis of FACS-purified choroid plexus epithelial cells also predicts their cell-type-specific secretome. Spatial domains with distinct protein expression profiles were observed within each choroid plexus. We propose that regional differences between choroid plexi contribute to dynamic signaling gradients across the mammalian cerebroventricular system.


Asunto(s)
Líquido Cefalorraquídeo/metabolismo , Plexo Coroideo/metabolismo , Cuarto Ventrículo/metabolismo , Ventrículos Laterales/metabolismo , Transcriptoma , Envejecimiento/metabolismo , Animales , Células Epiteliales/metabolismo , Femenino , Humanos , Macaca mulatta , Masculino , Ratones
14.
Sci Adv ; 10(20): eadl0161, 2024 May 17.
Artículo en Inglés | MEDLINE | ID: mdl-38748791

RESUMEN

Reliable prediction of T cell specificity against antigenic signatures is a formidable task, complicated by the immense diversity of T cell receptor and antigen sequence space and the resulting limited availability of training sets for inferential models. Recent modeling efforts have demonstrated the advantage of incorporating structural information to overcome the need for extensive training sequence data, yet disentangling the heterogeneous TCR-antigen interface to accurately predict MHC-allele-restricted TCR-peptide interactions has remained challenging. Here, we present RACER-m, a coarse-grained structural model leveraging key biophysical information from the diversity of publicly available TCR-antigen crystal structures. Explicit inclusion of structural content substantially reduces the required number of training examples and maintains reliable predictions of TCR-recognition specificity and sensitivity across diverse biological contexts. Our model capably identifies biophysically meaningful point-mutant peptides that affect binding affinity, distinguishing its ability in predicting TCR specificity of point-mutants from alternative sequence-based methods. Its application is broadly applicable to studies involving both closely related and structurally diverse TCR-peptide pairs.


Asunto(s)
Receptores de Antígenos de Linfocitos T , Linfocitos T , Receptores de Antígenos de Linfocitos T/química , Receptores de Antígenos de Linfocitos T/metabolismo , Receptores de Antígenos de Linfocitos T/inmunología , Receptores de Antígenos de Linfocitos T/genética , Linfocitos T/inmunología , Linfocitos T/metabolismo , Humanos , Unión Proteica , Modelos Moleculares , Péptidos/química , Péptidos/metabolismo , Especificidad del Receptor de Antígeno de Linfocitos T , Conformación Proteica
15.
Nat Commun ; 15(1): 1612, 2024 Feb 22.
Artículo en Inglés | MEDLINE | ID: mdl-38383544

RESUMEN

Plasmids carry genes conferring antimicrobial resistance and other clinically important traits, and contribute to the rapid dissemination of such genes. Previous studies using complete plasmid assemblies, which are essential for reliable inference, have been small and/or limited to plasmids carrying antimicrobial resistance genes (ARGs). In this study, we sequenced 1,880 complete plasmids from 738 isolates from bloodstream infections in Oxfordshire, UK. The bacteria had been originally isolated in 2009 (194 isolates) and 2018 (368 isolates), plus a stratified selection from intervening years (176 isolates). We demonstrate that plasmids are largely, but not entirely, constrained to a single host species, although there is substantial overlap between species of plasmid gene-repertoire. Most ARGs are carried by a relatively small number of plasmid groups with biological features that are predictable. Plasmids carrying ARGs (including those encoding carbapenemases) share a putative 'backbone' of core genes with those carrying no such genes. These findings suggest that future surveillance should, in addition to tracking plasmids currently associated with clinically important genes, focus on identifying and monitoring the dissemination of high-risk plasmid groups with the potential to rapidly acquire and disseminate these genes.


Asunto(s)
Antibacterianos , Bacterias , Plásmidos/genética , Bacterias/genética
16.
Microb Genom ; 9(5)2023 05.
Artículo en Inglés | MEDLINE | ID: mdl-37145848

RESUMEN

Wastewater-based epidemiology (WBE) for population-level surveillance of antimicrobial resistance (AMR) is gaining significant traction, but the impact of wastewater sampling methods on results is unclear. In this study, we characterized taxonomic and resistome differences between single-timepoint-grab and 24 h composites of wastewater influent from a large UK-based wastewater treatment work [WWTW (population equivalent: 223 435)]. We autosampled hourly influent grab samples (n=72) over three consecutive weekdays, and prepared additional 24 h composites (n=3) from respective grabs. For taxonomic profiling, metagenomic DNA was extracted from all samples and 16S rRNA gene sequencing was performed. One composite and six grabs from day 1 underwent metagenomic sequencing for metagenomic dissimilarity estimation and resistome profiling. Taxonomic abundances of phyla varied significantly across hourly grab samples but followed a repeating diurnal pattern for all 3 days. Hierarchical clustering grouped grab samples into four time periods dissimilar in both 16S rRNA gene-based profiles and metagenomic distances. 24H-composites resembled mean daily phyla abundances and showed low variability of taxonomic profiles. Of the 122 AMR gene families (AGFs) identified across all day 1 samples, single grab samples identified a median of six (IQR: 5-8) AGFs not seen in the composite. However, 36/36 of these hits were at lateral coverage <0.5 (median: 0.19; interquartile range: 0.16-0.22) and potential false positives. Conversely, the 24H-composite identified three AGFs not seen in any grab with higher lateral coverage (0.82; 0.55-0.84). Additionally, several clinically significant human AGFs (bla VIM, bla IMP, bla KPC) were intermittently or completely missed by grab sampling but captured by the 24 h composite. Wastewater influent undergoes significant taxonomic and resistome changes on short timescales potentially affecting interpretation of results based on sampling strategy. Grab samples are more convenient and potentially capture low-prevalence/transient targets but are less comprehensive and temporally variable. Therefore, we recommend 24H-composite sampling where feasible. Further validation and optimization of WBE methods is vital for its development into a robust AMR surveillance approach.


Asunto(s)
Metagenoma , Aguas Residuales , Humanos , ARN Ribosómico 16S/genética
17.
Front Microbiol ; 14: 1070340, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-36998408

RESUMEN

Introduction: There are concerns that antimicrobial usage (AMU) is driving an increase in multi-drug resistant (MDR) bacteria so treatment of microbial infections is becoming harder in humans and animals. The aim of this study was to evaluate factors, including usage, that affect antimicrobial resistance (AMR) on farm over time. Methods: A population of 14 cattle, sheep and pig farms within a defined area of England were sampled three times over a year to collect data on AMR in faecal Enterobacterales flora; AMU; and husbandry or management practices. Ten pooled samples were collected at each visit, with each comprising of 10 pinches of fresh faeces. Up to 14 isolates per visit were whole genome sequenced to determine presence of AMR genes. Results: Sheep farms had very low AMU in comparison to the other species and very few sheep isolates were genotypically resistant at any time point. AMR genes were detected persistently across pig farms at all visits, even on farms with low AMU, whereas AMR bacteria was consistently lower on cattle farms than pigs, even for those with comparably high AMU. MDR bacteria was also more commonly detected on pig farms than any other livestock species. Discussion: The results may be explained by a complex combination of factors on pig farms including historic AMU; co-selection of AMR bacteria; variation in amounts of antimicrobials used between visits; potential persistence in environmental reservoirs of AMR bacteria; or importation of pigs with AMR microbiota from supplying farms. Pig farms may also be at increased risk of AMR due to the greater use of oral routes of group antimicrobial treatment, which were less targeted than cattle treatments; the latter mostly administered to individual animals. Also, farms which exhibited either increasing or decreasing trends of AMR across the study did not have corresponding trends in their AMU. Therefore, our results suggest that factors other than AMU on individual farms are important for persistence of AMR bacteria on farms, which may be operating at the farm and livestock species level.

18.
Elife ; 122023 Mar 24.
Artículo en Inglés | MEDLINE | ID: mdl-36961866

RESUMEN

Plasmids enable the dissemination of antimicrobial resistance (AMR) in common Enterobacterales pathogens, representing a major public health challenge. However, the extent of plasmid sharing and evolution between Enterobacterales causing human infections and other niches remains unclear, including the emergence of resistance plasmids. Dense, unselected sampling is essential to developing our understanding of plasmid epidemiology and designing appropriate interventions to limit the emergence and dissemination of plasmid-associated AMR. We established a geographically and temporally restricted collection of human bloodstream infection (BSI)-associated, livestock-associated (cattle, pig, poultry, and sheep faeces, farm soils) and wastewater treatment work (WwTW)-associated (influent, effluent, waterways upstream/downstream of effluent outlets) Enterobacterales. Isolates were collected between 2008 and 2020 from sites <60 km apart in Oxfordshire, UK. Pangenome analysis of plasmid clusters revealed shared 'backbones', with phylogenies suggesting an intertwined ecology where well-conserved plasmid backbones carry diverse accessory functions, including AMR genes. Many plasmid 'backbones' were seen across species and niches, raising the possibility that plasmid movement between these followed by rapid accessory gene change could be relatively common. Overall, the signature of identical plasmid sharing is likely to be a highly transient one, implying that plasmid movement might be occurring at greater rates than previously estimated, raising a challenge for future genomic One Health studies.


Asunto(s)
Gammaproteobacteria , Sepsis , Humanos , Animales , Bovinos , Porcinos , Ovinos/genética , Escherichia coli/genética , Ganado/genética , Aguas Residuales , Plásmidos/genética , Klebsiella pneumoniae/genética , Reino Unido , Antibacterianos , beta-Lactamasas/genética , Pruebas de Sensibilidad Microbiana
19.
Clin Cancer Res ; 29(11): 2131-2143, 2023 06 01.
Artículo en Inglés | MEDLINE | ID: mdl-36884217

RESUMEN

PURPOSE: Claudin-6 (CLDN6) is expressed at elevated levels in multiple human cancers including ovarian and endometrial malignancies, with little or no detectable expression in normal adult tissue. This expression profile makes CLDN6 an ideal target for development of a potential therapeutic antibody-drug conjugate (ADC). This study describes the generation and preclinical characterization of CLDN6-23-ADC, an ADC consisting of a humanized anti-CLDN6 monoclonal antibody coupled to monomethyl auristatin E (MMAE) via a cleavable linker. EXPERIMENTAL DESIGN: A fully humanized anti-CLDN6 antibody was conjugated to MMAE resulting in the potential therapeutic ADC, CLDN6-23-ADC. The antitumor efficacy of CLDN6-23-ADC was assessed for antitumor efficacy in CLDN6-positive (CLDN6+) and -negative (CLDN6-) xenografts and patient-derived xenograft (PDX) models of human cancers. RESULTS: CLDN6-23-ADC selectively binds to CLDN6, versus other CLDN family members, inhibits the proliferation of CLDN6+ cancer cells in vitro, and is rapidly internalized in CLDN6+ cells. Robust tumor regressions were observed in multiple CLDN6+ xenograft models and tumor inhibition led to markedly enhanced survival of CLDN6+ PDX tumors following treatment with CLDN6-23-ADC. IHC assessment of cancer tissue microarrays demonstrate elevated levels of CLDN6 in 29% of ovarian epithelial carcinomas. Approximately 45% of high-grade serous ovarian carcinomas and 11% of endometrial carcinomas are positive for the target. CONCLUSIONS: We report the development of a novel ADC, CLDN6-23-ADC, that selectively targets CLDN6, a potential onco-fetal-antigen which is highly expressed in ovarian and endometrial cancers. CLDN6-23-ADC exhibits robust tumor regressions in mouse models of human ovarian and endometrial cancers and is currently undergoing phase I study.


Asunto(s)
Neoplasias Endometriales , Inmunoconjugados , Ratones , Animales , Humanos , Femenino , Anticuerpos Monoclonales/farmacología , Anticuerpos Monoclonales/uso terapéutico , Ensayos Antitumor por Modelo de Xenoinjerto , Anticuerpos Monoclonales Humanizados , Inmunoconjugados/farmacología , Inmunoconjugados/uso terapéutico , Modelos Animales de Enfermedad , Neoplasias Endometriales/tratamiento farmacológico , Línea Celular Tumoral
20.
NPJ Genom Med ; 8(1): 5, 2023 Feb 14.
Artículo en Inglés | MEDLINE | ID: mdl-36788231

RESUMEN

Universal newborn screening (NBS) is a highly successful public health intervention. Archived dried bloodspots (DBS) collected for NBS represent a rich resource for population genomic studies. To fully harness this resource in such studies, DBS must yield high-quality genomic DNA (gDNA) for whole genome sequencing (WGS). In this pilot study, we hypothesized that gDNA of sufficient quality and quantity for WGS could be extracted from archived DBS up to 20 years old without PCR (Polymerase Chain Reaction) amplification. We describe simple methods for gDNA extraction and WGS library preparation from several types of DBS. We tested these methods in DBS from 25 individuals who had previously undergone diagnostic, clinical WGS and 29 randomly selected DBS cards collected for NBS from the California State Biobank. While gDNA from DBS had significantly less yield than from EDTA blood from the same individuals, it was of sufficient quality and quantity for WGS without PCR. All samples DBS yielded WGS that met quality control metrics for high-confidence variant calling. Twenty-eight variants of various types that had been reported clinically in 19 samples were recapitulated in WGS from DBS. There were no significant effects of age or paper type on WGS quality. Archived DBS appear to be a suitable sample type for WGS in population genomic studies.

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