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Showing papers by "Medical Research Council published in 2021"


Journal ArticleDOI
TL;DR: In this article, the authors present a set of guidelines for investigators to select and interpret methods to examine autophagy and related processes, and for reviewers to provide realistic and reasonable critiques of reports that are focused on these processes.
Abstract: In 2008, we published the first set of guidelines for standardizing research in autophagy. Since then, this topic has received increasing attention, and many scientists have entered the field. Our knowledge base and relevant new technologies have also been expanding. Thus, it is important to formulate on a regular basis updated guidelines for monitoring autophagy in different organisms. Despite numerous reviews, there continues to be confusion regarding acceptable methods to evaluate autophagy, especially in multicellular eukaryotes. Here, we present a set of guidelines for investigators to select and interpret methods to examine autophagy and related processes, and for reviewers to provide realistic and reasonable critiques of reports that are focused on these processes. These guidelines are not meant to be a dogmatic set of rules, because the appropriateness of any assay largely depends on the question being asked and the system being used. Moreover, no individual assay is perfect for every situation, calling for the use of multiple techniques to properly monitor autophagy in each experimental setting. Finally, several core components of the autophagy machinery have been implicated in distinct autophagic processes (canonical and noncanonical autophagy), implying that genetic approaches to block autophagy should rely on targeting two or more autophagy-related genes that ideally participate in distinct steps of the pathway. Along similar lines, because multiple proteins involved in autophagy also regulate other cellular pathways including apoptosis, not all of them can be used as a specific marker for bona fide autophagic responses. Here, we critically discuss current methods of assessing autophagy and the information they can, or cannot, provide. Our ultimate goal is to encourage intellectual and technical innovation in the field.

1,129 citations


Journal ArticleDOI
30 Sep 2021-BMJ
TL;DR: JBl received funding from NIHR Biomedical Research Centre at University Hospitals Bristol NHS Foundation Trust and the University of Bristol and by the MRC ConDuCT-II Hub (Collaboration and innovation for Difficult and Complex randomised controlled Trials In Invasive procedures).
Abstract: The UK Medical Research Council’s widely used guidance for developing and evaluating complex interventions has been replaced by a new framework, commissioned jointly by the Medical Research Council and the National Institute for Health Research, which takes account of recent developments in theory and methods and the need to maximise the efficiency, use, and impact of research.

1,080 citations


Journal ArticleDOI
06 Sep 2021-Nature
TL;DR: The B.617.1.2 spike protein was able to mediate highly efficient syncytium formation that was less sensitive to inhibition by neutralizing antibody, compared with that of wild-type spike as discussed by the authors.
Abstract: The B.1.617.2 (Delta) variant of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) was first identified in the state of Maharashtra in late 2020 and spread throughout India, outcompeting pre-existing lineages including B.1.617.1 (Kappa) and B.1.1.7 (Alpha)1. In vitro, B.1.617.2 is sixfold less sensitive to serum neutralizing antibodies from recovered individuals, and eightfold less sensitive to vaccine-elicited antibodies, compared with wild-type Wuhan-1 bearing D614G. Serum neutralizing titres against B.1.617.2 were lower in ChAdOx1 vaccinees than in BNT162b2 vaccinees. B.1.617.2 spike pseudotyped viruses exhibited compromised sensitivity to monoclonal antibodies to the receptor-binding domain and the amino-terminal domain. B.1.617.2 demonstrated higher replication efficiency than B.1.1.7 in both airway organoid and human airway epithelial systems, associated with B.1.617.2 spike being in a predominantly cleaved state compared with B.1.1.7 spike. The B.1.617.2 spike protein was able to mediate highly efficient syncytium formation that was less sensitive to inhibition by neutralizing antibody, compared with that of wild-type spike. We also observed that B.1.617.2 had higher replication and spike-mediated entry than B.1.617.1, potentially explaining the B.1.617.2 dominance. In an analysis of more than 130 SARS-CoV-2-infected health care workers across three centres in India during a period of mixed lineage circulation, we observed reduced ChAdOx1 vaccine effectiveness against B.1.617.2 relative to non-B.1.617.2, with the caveat of possible residual confounding. Compromised vaccine efficacy against the highly fit and immune-evasive B.1.617.2 Delta variant warrants continued infection control measures in the post-vaccination era.

839 citations


Journal ArticleDOI
19 Feb 2021-Science
TL;DR: The results indicate that, by using effective interventions, some countries could control the epidemic while avoiding stay-at-home orders, and this model accounts for uncertainty in key epidemiological parameters, such as the average delay from infection to death.
Abstract: Governments are attempting to control the COVID-19 pandemic with nonpharmaceutical interventions (NPIs). However, the effectiveness of different NPIs at reducing transmission is poorly understood. We gathered chronological data on the implementation of NPIs for several European, and other, countries between January and the end of May 2020. We estimate the effectiveness of NPIs, ranging from limiting gathering sizes, business closures, and closure of educational institutions to stay-at-home orders. To do so, we used a Bayesian hierarchical model that links NPI implementation dates to national case and death counts and supported the results with extensive empirical validation. Closing all educational institutions, limiting gatherings to 10 people or less, and closing face-to-face businesses each reduced transmission considerably. The additional effect of stay-at-home orders was comparatively small.

674 citations


Journal ArticleDOI
TL;DR: The current knowledge of COVID-19 in pregnancy and signpost areas for further research are explored to minimise its impact for women and their children.
Abstract: There are many unknowns for pregnant women during the coronavirus disease 2019 (COVID-19) pandemic. Clinical experience of pregnancies complicated with infection by other coronaviruses e.g., Severe Acute Respiratory Syndrome (SARS) and Middle Eastern Respiratory Syndrome, has led to pregnant woman being considered potentially vulnerable to severe SARS-CoV-2 infection. Physiological changes during pregnancy have a significant impact on the immune system, respiratory system, cardiovascular function, and coagulation. These may have positive or negative effects on COVID-19 disease progression. The impact of SARS-CoV-2 in pregnancy remains to be determined, and a concerted, global effort is required to determine the effects on implantation, fetal growth and development, labor, and neonatal health. Asymptomatic infection presents a further challenge regarding service provision, prevention, and management. Besides the direct impacts of the disease, a plethora of indirect consequences of the pandemic adversely affect maternal health, including reduced access to reproductive health services, increased mental health strain, and increased socioeconomic deprivation. In this review, we explore the current knowledge of COVID-19 in pregnancy and highlight areas for further research to minimize its impact for women and their children.

376 citations


Journal ArticleDOI
12 Feb 2021-Science
TL;DR: The United Kingdom's COVID-19 epidemic during early 2020 was one of world's largest and was unusually well represented by virus genomic sampling as mentioned in this paper, which determined the fine-scale genetic lineage structure of this epidemic through analysis of 50,887 severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) genomes, including 26,181 from the UK sampled throughout the country's first wave of infection.
Abstract: The United Kingdom’s COVID-19 epidemic during early 2020 was one of world’s largest and was unusually well represented by virus genomic sampling. We determined the fine-scale genetic lineage structure of this epidemic through analysis of 50,887 severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) genomes, including 26,181 from the UK sampled throughout the country’s first wave of infection. Using large-scale phylogenetic analyses combined with epidemiological and travel data, we quantified the size, spatiotemporal origins, and persistence of genetically distinct UK transmission lineages. Rapid fluctuations in virus importation rates resulted in >1000 lineages; those introduced prior to national lockdown tended to be larger and more dispersed. Lineage importation and regional lineage diversity declined after lockdown, whereas lineage elimination was size-dependent. We discuss the implications of our genetic perspective on transmission dynamics for COVID-19 epidemiology and control.

285 citations


Journal ArticleDOI
16 Apr 2021-Science
TL;DR: In this paper, the authors used deep-sequenced 1313 clinical samples from the United Kingdom to characterize within-host diversity and transmission of SARS-CoV-2.
Abstract: Extensive global sampling and sequencing of the pandemic virus severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) have enabled researchers to monitor its spread and to identify concerning new variants. Two important determinants of variant spread are how frequently they arise within individuals and how likely they are to be transmitted. To characterize within-host diversity and transmission, we deep-sequenced 1313 clinical samples from the United Kingdom. SARS-CoV-2 infections are characterized by low levels of within-host diversity when viral loads are high and by a narrow bottleneck at transmission. Most variants are either lost or occasionally fixed at the point of transmission, with minimal persistence of shared diversity, patterns that are readily observable on the phylogenetic tree. Our results suggest that transmission-enhancing and/or immune-escape SARS-CoV-2 variants are likely to arise infrequently but could spread rapidly if successfully transmitted.

233 citations


Journal ArticleDOI
04 Feb 2021-Cell
TL;DR: In this paper, single-cell RNA sequencing and spatial transcriptomics were used to characterize intestinal morphogenesis through time and identify 101 cell states including epithelial and mesenchymal progenitor populations and programs linked to key morphogenetic milestones.

189 citations


Journal ArticleDOI
Ji Chen1, Ji Chen2, Cassandra N. Spracklen3, Cassandra N. Spracklen4  +475 moreInstitutions (146)
TL;DR: This paper aggregated genome-wide association studies comprising up to 281,416 individuals without diabetes (30% non-European ancestry) for whom fasting glucose, 2-h glucose after an oral glucose challenge, glycated hemoglobin and fasting insulin data were available.
Abstract: Glycemic traits are used to diagnose and monitor type 2 diabetes and cardiometabolic health. To date, most genetic studies of glycemic traits have focused on individuals of European ancestry. Here we aggregated genome-wide association studies comprising up to 281,416 individuals without diabetes (30% non-European ancestry) for whom fasting glucose, 2-h glucose after an oral glucose challenge, glycated hemoglobin and fasting insulin data were available. Trans-ancestry and single-ancestry meta-analyses identified 242 loci (99 novel; P < 5 × 10-8), 80% of which had no significant evidence of between-ancestry heterogeneity. Analyses restricted to individuals of European ancestry with equivalent sample size would have led to 24 fewer new loci. Compared with single-ancestry analyses, equivalent-sized trans-ancestry fine-mapping reduced the number of estimated variants in 99% credible sets by a median of 37.5%. Genomic-feature, gene-expression and gene-set analyses revealed distinct biological signatures for each trait, highlighting different underlying biological pathways. Our results increase our understanding of diabetes pathophysiology by using trans-ancestry studies for improved power and resolution.

178 citations


Journal ArticleDOI
Paul Bastard1, Paul Bastard2, Paul Bastard3, Elizaveta Orlova, Leila S. Sozaeva, Romain Lévy2, Romain Lévy3, Alyssa James4, Monica M. Schmitt4, Sebastian Ochoa4, Maria Kareva, Yulia Rodina, Adrian Gervais3, Adrian Gervais2, Tom Le Voyer2, Tom Le Voyer3, Jérémie Rosain3, Jérémie Rosain2, Quentin Philippot3, Quentin Philippot2, Anna-Lena Neehus3, Anna-Lena Neehus2, Elana Shaw4, Mélanie Migaud3, Lucy Bizien3, Olov Ekwall5, Stefan Berg5, Guglielmo Beccuti6, Lucia Ghizzoni6, Gérard Thiriez, Arthur Pavot, Cécile Goujard3, Marie-Louise Frémond2, Edwin Carter7, Anya Rothenbuhler, Agnès Linglart, Brigite Mignot, Aurélie Comte, Nathalie Cheikh, Olivier Hermine2, Lars Breivik8, Eystein S. Husebye9, Eystein S. Husebye10, Eystein S. Husebye8, Sébastien Humbert, Pierre Rohrlich, Alain Coaquette, Fanny Vuoto, Karine Faure, Nizar Mahlaoui11, Primož Kotnik12, Primož Kotnik13, Tadej Battelino12, Tadej Battelino13, Katarina Trebušak Podkrajšek13, Katarina Trebušak Podkrajšek12, Kai Kisand14, Elise M. N. Ferré4, Thomas DiMaggio4, Lindsey B. Rosen4, Peter D. Burbelo4, Martin Mcintyre15, Nelli Y Kann, Anna Shcherbina, Maria Pavlova, Anna Kolodkina, Steven M. Holland4, Shen-Ying Zhang1, Shen-Ying Zhang3, Shen-Ying Zhang2, Yanick J. Crow2, Yanick J. Crow7, Luigi D. Notarangelo4, Helen C. Su4, Laurent Abel2, Laurent Abel3, Laurent Abel1, Mark S. Anderson16, Emmanuelle Jouanguy2, Emmanuelle Jouanguy1, Emmanuelle Jouanguy3, Bénédicte Neven2, Anne Puel2, Anne Puel3, Anne Puel1, Jean-Laurent Casanova, Michail S. Lionakis4 
TL;DR: In this paper, the authors report 22 APS-1 patients from 21 kindreds in seven countries, aged between 8 and 48 yr and infected with SARS-CoV-2 since February 2020.
Abstract: Patients with biallelic loss-of-function variants of AIRE suffer from autoimmune polyendocrine syndrome type-1 (APS-1) and produce a broad range of autoantibodies (auto-Abs), including circulating auto-Abs neutralizing most type I interferons (IFNs). These auto-Abs were recently reported to account for at least 10% of cases of life-threatening COVID-19 pneumonia in the general population. We report 22 APS-1 patients from 21 kindreds in seven countries, aged between 8 and 48 yr and infected with SARS-CoV-2 since February 2020. The 21 patients tested had auto-Abs neutralizing IFN-α subtypes and/or IFN-ω; one had anti-IFN-β and another anti-IFN-e, but none had anti-IFN-κ. Strikingly, 19 patients (86%) were hospitalized for COVID-19 pneumonia, including 15 (68%) admitted to an intensive care unit, 11 (50%) who required mechanical ventilation, and four (18%) who died. Ambulatory disease in three patients (14%) was possibly accounted for by prior or early specific interventions. Preexisting auto-Abs neutralizing type I IFNs in APS-1 patients confer a very high risk of life-threatening COVID-19 pneumonia at any age.

165 citations


Journal ArticleDOI
14 Oct 2021-Science
TL;DR: In this paper, a Bayesian model explains the growth advantage of Delta through a combination of increased transmissibility and reduced sensitivity to immune responses generated against earlier variants (median estimates; ×1.5-fold, 20% reduction).
Abstract: Delhi, the national capital of India, has experienced multiple SARS-CoV-2 outbreaks in 2020 and reached population seropositivity of over 50% by 2021. During April 2021, the city became overwhelmed by COVID-19 cases and fatalities, as a new variant B.1.617.2 (Delta) replaced B.1.1.7 (Alpha). A Bayesian model explains the growth advantage of Delta through a combination of increased transmissibility and reduced sensitivity to immune responses generated against earlier variants (median estimates; ×1.5-fold, 20% reduction). Seropositivity of an employee and family cohort increased from 42% to 87.5% between March and July 2021, with 27% reinfections, as judged by increased antibody concentration after a previous decline. The likely high transmissibility and partial evasion of immunity by the Delta variant contributed to an overwhelming surge in Delhi.

Journal ArticleDOI
TL;DR: Age (young adults, particularly those aged 17–24 years) was an important initial driver of increased positivity rates in the second wave, and a substantial proportion of infections were in individuals not reporting symptoms around their positive test, indicating that continued monitoring for SARS-CoV-2 in the community will be important for managing the COVID-19 pandemic moving forwards.
Abstract: Summary Background Decisions about the continued need for control measures to contain the spread of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) rely on accurate and up-to-date information about the number of people testing positive for SARS-CoV-2 and risk factors for testing positive. Existing surveillance systems are generally not based on population samples and are not longitudinal in design. Methods Samples were collected from individuals aged 2 years and older living in private households in England that were randomly selected from address lists and previous Office for National Statistics surveys in repeated cross-sectional household surveys with additional serial sampling and longitudinal follow-up. Participants completed a questionnaire and did nose and throat self-swabs. The percentage of individuals testing positive for SARS-CoV-2 RNA was estimated over time by use of dynamic multilevel regression and poststratification, to account for potential residual non-representativeness. Potential changes in risk factors for testing positive over time were also assessed. The study is registered with the ISRCTN Registry, ISRCTN21086382. Findings Between April 26 and Nov 1, 2020, results were available from 1 191 170 samples from 280 327 individuals; 5231 samples were positive overall, from 3923 individuals. The percentage of people testing positive for SARS-CoV-2 changed substantially over time, with an initial decrease between April 26 and June 28, 2020, from 0·40% (95% credible interval 0·29–0·54) to 0·06% (0·04–0·07), followed by low levels during July and August, 2020, before substantial increases at the end of August, 2020, with percentages testing positive above 1% from the end of October, 2020. Having a patient-facing role and working outside your home were important risk factors for testing positive for SARS-CoV-2 at the end of the first wave (April 26 to June 28, 2020), but not in the second wave (from the end of August to Nov 1, 2020). Age (young adults, particularly those aged 17–24 years) was an important initial driver of increased positivity rates in the second wave. For example, the estimated percentage of individuals testing positive was more than six times higher in those aged 17–24 years than in those aged 70 years or older at the end of September, 2020. A substantial proportion of infections were in individuals not reporting symptoms around their positive test (45–68%, dependent on calendar time. Interpretation Important risk factors for testing positive for SARS-CoV-2 varied substantially between the part of the first wave that was captured by the study (April to June, 2020) and the first part of the second wave of increased positivity rates (end of August to Nov 1, 2020), and a substantial proportion of infections were in individuals not reporting symptoms, indicating that continued monitoring for SARS-CoV-2 in the community will be important for managing the COVID-19 pandemic moving forwards. Funding Department of Health and Social Care.

Journal ArticleDOI
23 Sep 2021-Nature
TL;DR: In this paper, the depletion of 15 structurally diverse drugs by 25 representative strains of gut bacteria revealed 70 bacteria-drug interactions, 29 of which had not to our knowledge been reported before.
Abstract: Bacteria in the gut can modulate the availability and efficacy of therapeutic drugs. However, the systematic mapping of the interactions between drugs and bacteria has only started recently1 and the main underlying mechanism proposed is the chemical transformation of drugs by microorganisms (biotransformation). Here we investigated the depletion of 15 structurally diverse drugs by 25 representative strains of gut bacteria. This revealed 70 bacteria-drug interactions, 29 of which had not to our knowledge been reported before. Over half of the new interactions can be ascribed to bioaccumulation; that is, bacteria storing the drug intracellularly without chemically modifying it, and in most cases without the growth of the bacteria being affected. As a case in point, we studied the molecular basis of bioaccumulation of the widely used antidepressant duloxetine by using click chemistry, thermal proteome profiling and metabolomics. We find that duloxetine binds to several metabolic enzymes and changes the metabolite secretion of the respective bacteria. When tested in a defined microbial community of accumulators and non-accumulators, duloxetine markedly altered the composition of the community through metabolic cross-feeding. We further validated our findings in an animal model, showing that bioaccumulating bacteria attenuate the behavioural response of Caenorhabditis elegans to duloxetine. Together, our results show that bioaccumulation by gut bacteria may be a common mechanism that alters drug availability and bacterial metabolism, with implications for microbiota composition, pharmacokinetics, side effects and drug responses, probably in an individual manner.

Journal ArticleDOI
TL;DR: In this paper, the authors use genome-scale metabolic modeling to assess the potential for resource competition and metabolic cooperation in large co-occurring groups (up to 40 members) across thousands of habitats.
Abstract: Resource competition and metabolic cross-feeding are among the main drivers of microbial community assembly. Yet the degree to which these two conflicting forces are reflected in the composition of natural communities has not been systematically investigated. Here, we use genome-scale metabolic modelling to assess the potential for resource competition and metabolic cooperation in large co-occurring groups (up to 40 members) across thousands of habitats. Our analysis reveals two distinct community types, which are clustered at opposite ends of a spectrum in a trade-off between competition and cooperation. At one end are highly cooperative communities, characterized by smaller genomes and multiple auxotrophies. At the other end are highly competitive communities, which feature larger genomes and overlapping nutritional requirements, and harbour more genes related to antimicrobial activity. The latter are mainly present in soils, whereas the former are found in both free-living and host-associated habitats. Community-scale flux simulations show that, whereas competitive communities can better resist species invasion but not nutrient shift, cooperative communities are susceptible to species invasion but resilient to nutrient change. We also show, by analysing an additional data set, that colonization by probiotic species is positively associated with the presence of cooperative species in the recipient microbiome. Together, our results highlight the bifurcation between competitive and cooperative metabolism in the assembly of natural communities and its implications for community modulation.

Journal ArticleDOI
TL;DR: In this paper, the authors examined trends in the prevalence of non-B.1.7 lineages in London and other English regions using passive-case detection PCR data, cross-sectional community infection surveys, genomic surveillance, and wastewater monitoring.

Journal ArticleDOI
TL;DR: In this paper, the authors estimate the effectiveness of 17 nonpharmaceutical interventions in Europe's second wave from subnational case and death data by introducing a flexible hierarchical Bayesian transmission model and collecting the largest dataset of NPI implementation dates across Europe.
Abstract: European governments use non-pharmaceutical interventions (NPIs) to control resurging waves of COVID-19. However, they only have outdated estimates for how effective individual NPIs were in the first wave. We estimate the effectiveness of 17 NPIs in Europe's second wave from subnational case and death data by introducing a flexible hierarchical Bayesian transmission model and collecting the largest dataset of NPI implementation dates across Europe. Business closures, educational institution closures, and gathering bans reduced transmission, but reduced it less than they did in the first wave. This difference is likely due to organisational safety measures and individual protective behaviours-such as distancing-which made various areas of public life safer and thereby reduced the effect of closing them. Specifically, we find smaller effects for closing educational institutions, suggesting that stringent safety measures made schools safer compared to the first wave. Second-wave estimates outperform previous estimates at predicting transmission in Europe's third wave.

Journal ArticleDOI
TL;DR: In this paper, the authors investigated how the immune system may be affected by SARS-CoV-2 infection of cancer patients, including those with advanced disease, and showed that recovered solid cancer patients' immunophenotypes resemble those of non-virus-exposed cancer patients.

Posted ContentDOI
22 Jun 2021-bioRxiv
TL;DR: Combined epidemiological and in vitro data indicate that the dominance of the Delta variant in India has been most likely driven by a combination of evasion of neutralising antibodies in previously infected individuals and increased virus infectivity.
Abstract: The SARS-CoV-2 B.1.617.2 (Delta) variant was first identified in the state of Maharashtra in late 2020 and has spread throughout India, displacing the B.1.1.7 (Alpha) variant and other pre-existing lineages. Mathematical modelling indicates that the growth advantage is most likely explained by a combination of increased transmissibility and immune evasion. Indeed in vitro, the delta variant is less sensitive to neutralising antibodies in sera from recovered individuals, with higher replication efficiency as compared to the Alpha variant. In an analysis of vaccine breakthrough in over 100 healthcare workers across three centres in India, the Delta variant was responsible for greater transmission between HCW as compared to B.1.1.7 or B.1.617.1 (mean cluster size 3.2 versus 1.1, p

Journal ArticleDOI
TL;DR: In this article, the authors discussed three areas-cancer genomics, cancer immunology and cell-therapy manufacturing-that are essential to the effective translation of T-cell therapies in the treatment of solid malignancies.
Abstract: Cancer is a leading cause of death worldwide and, despite new targeted therapies and immunotherapies, many patients with advanced-stage- or high-risk cancers still die, owing to metastatic disease Adoptive T-cell therapy, involving the autologous or allogeneic transplant of tumour-infiltrating lymphocytes or genetically modified T cells expressing novel T-cell receptors or chimeric antigen receptors, has shown promise in the treatment of cancer patients, leading to durable responses and, in some cases, cure Technological advances in genomics, computational biology, immunology and cell manufacturing have brought the aspiration of individualised therapies for cancer patients closer to reality This new era of cell-based individualised therapeutics challenges the traditional standards of therapeutic interventions and provides opportunities for a paradigm shift in our approach to cancer therapy Invited speakers at a 2020 symposium discussed three areas-cancer genomics, cancer immunology and cell-therapy manufacturing-that are essential to the effective translation of T-cell therapies in the treatment of solid malignancies Key advances have been made in understanding genetic intratumour heterogeneity, and strategies to accurately identify neoantigens, overcome T-cell exhaustion and circumvent tumour immunosuppression after cell-therapy infusion are being developed Advances are being made in cell-manufacturing approaches that have the potential to establish cell-therapies as credible therapeutic options T-cell therapies face many challenges but hold great promise for improving clinical outcomes for patients with solid tumours

Journal ArticleDOI
TL;DR: In this article, a fluorescent probe (DAOTA-M2) in conjunction with fluorescence lifetime imaging microscopy (FLIM) can identify G-quadruplexes (G4s) within nuclei of live and fixed cells.
Abstract: Guanine rich regions of oligonucleotides fold into quadruple-stranded structures called G-quadruplexes (G4s). Increasing evidence suggests that these G4 structures form in vivo and play a crucial role in cellular processes. However, their direct observation in live cells remains a challenge. Here we demonstrate that a fluorescent probe (DAOTA-M2) in conjunction with fluorescence lifetime imaging microscopy (FLIM) can identify G4s within nuclei of live and fixed cells. We present a FLIM-based cellular assay to study the interaction of non-fluorescent small molecules with G4s and apply it to a wide range of drug candidates. We also demonstrate that DAOTA-M2 can be used to study G4 stability in live cells. Reduction of FancJ and RTEL1 expression in mammalian cells increases the DAOTA-M2 lifetime and therefore suggests an increased number of G4s in these cells, implying that FancJ and RTEL1 play a role in resolving G4 structures in cellulo.


Posted ContentDOI
20 Aug 2021-medRxiv
TL;DR: In this paper, the authors trace viral, host, and social factors contributing to the scale and exponent of the fourth wave of SARS-CoV2 pandemic, when compared to preceding waves, in an epidemiological context.
Abstract: In April 2021, after successfully enduring three waves of the SARS-CoV2 pandemic in 2020, and having reached population seropositivity of about 50%, Delhi, the national capital of India was overwhelmed by the fourth wave Here, we trace viral, host, and social factors contributing to the scale and exponent of the fourth wave, when compared to preceding waves, in an epidemiological context Genomic surveillance data from Delhi and surrounding states shows an early phase of the upsurge driven by the entry of the more transmissible B117 variant of concern (VOC) into the region in January, with at least one B117 super spreader event in February 2021, relatable to known mass gatherings over this period This was followed by seeding of the B1617 VOC, which too is highly transmissible, with rapid expansion of B16172 sub-lineage outpacing all other lineages This unprecedented growth of cases occurred in the background of high seropositivity, but with low median neutralizing antibody levels, in a serially sampled cohort Vaccination breakthrough cases over this period were noted, disproportionately related to VOC in sequenced cases, but usually mild We find that this surge of SARS-CoV2 infections in Delhi is best explained by the introduction of a new highly transmissible VOC, B16172, with likely immune-evasion properties; insufficient neutralizing immunity, despite high seropositivity; and social behavior that promoted transmission

Journal ArticleDOI
28 Jul 2021-Nature
TL;DR: In this article, the authors identify a tandem BRCT-domain-associated ubiquitin-dependent recruitment motif (BUDR) in BRCA1-associated RING domain protein (BARD1) that, by engaging H2AK15ub, recruits BRCa1 to DSBs.
Abstract: Protein ubiquitination at sites of DNA double-strand breaks (DSBs) by RNF168 recruits BRCA1 and 53BP11,2, which are mediators of the homologous recombination and non-homologous end joining DSB repair pathways, respectively3. Non-homologous end joining relies on 53BP1 binding directly to ubiquitinated lysine 15 on H2A-type histones (H2AK15ub)4,5 (which is an RNF168-dependent modification6), but how RNF168 promotes BRCA1 recruitment and function remains unclear. Here we identify a tandem BRCT-domain-associated ubiquitin-dependent recruitment motif (BUDR) in BRCA1-associated RING domain protein 1 (BARD1) (the obligate partner protein of BRCA1) that, by engaging H2AK15ub, recruits BRCA1 to DSBs. Disruption of the BUDR of BARD1 compromises homologous recombination and renders cells hypersensitive to PARP inhibition and cisplatin. We further show that BARD1 binds nucleosomes through multivalent interactions: coordinated binding of H2AK15ub and unmethylated H4 lysine 20 by its adjacent BUDR and ankyrin repeat domains, respectively, provides high-affinity recognition of DNA lesions in replicated chromatin and promotes the homologous recombination activities of the BRCA1–BARD1 complex. Finally, our genetic epistasis experiments confirm that the need for BARD1 chromatin-binding activities can be entirely relieved upon deletion of RNF168 or 53BP1. Thus, our results demonstrate that by sensing DNA-damage-dependent and post-replication histone post-translation modification states, BRCA1–BARD1 complexes coordinate the antagonization of the 53BP1 pathway with promotion of homologous recombination, establishing a simple paradigm for the governance of the choice of DSB repair pathway. A tandem BRCT-domain-associated ubiquitin-dependent recruitment motif in BARD1 recruits BRCA1 to DNA double-strand breaks (DSBs) to promote homologous recombination and antagonize the 53BP1 DSB repair pathway that mediates non-homologous end joining.

Journal ArticleDOI
TL;DR: The associating challenges of phosphoproteomics that are linked to experimental design, sample preparation, and proteolytic digestion are outlined, and the future outlooks in phospho)proteomics are discussed, focusing on elucidating the noncanonical phosphoproteinome and deciphering the "dark phospho-isoforms".
Abstract: Phosphorylation is a form of protein posttranslational modification (PTM) that regulates many biological processes. Whereas phosphoproteomics is a scientific discipline that identifies and quantifies the phosphorylated proteome using mass spectrometry (MS). This task is extremely challenging as ~30% of the human proteome is phosphorylated; and each phosphoprotein may exist as multiple phospho-isoforms that are present in low abundance and stoichiometry. Hence, phosphopeptide enrichment techniques are indispensable to (phospho)proteomics laboratories. These enrichment methods encompass widely-adopted techniques such as (i) affinity-based chromatography; (ii) ion exchange and mixed-mode chromatography (iii) enrichment with phospho-specific antibodies and protein domains, and (iv) functionalized polymers and other less common but emerging technologies such as hydroxyapatite chromatography and precipitation with inorganic ions. Here, we review these techniques, their history, continuous development and evaluation. Besides, we outline associating challenges of phosphoproteomics that are linked to experimental design, sample preparation, and proteolytic digestion. In addition, we also discuss about the future outlooks in phosphoproteomics, focusing on elucidating the noncanonical phosphoproteome and deciphering the "dark phosphoproteome". © 2020 John Wiley & Sons Ltd. Mass Spec Rev.

Journal ArticleDOI
TL;DR: This diagnostic study investigates whether proteomic biomarkers may aid the prediction of transition to psychotic disorder in the clinical high-risk state and adolescent psychotic experiences in the general population.
Abstract: Importance: Biomarkers that are predictive of outcomes in individuals at risk of psychosis would facilitate individualized prognosis and stratification strategies. Objective: To investigate whether proteomic biomarkers may aid prediction of transition to psychotic disorder in the clinical high-risk (CHR) state and adolescent psychotic experiences (PEs) in the general population. Design, Setting, and Participants: This diagnostic study comprised 2 case-control studies nested within the European Network of National Schizophrenia Networks Studying Gene-Environment Interactions (EU-GEI) and the Avon Longitudinal Study of Parents and Children (ALSPAC). EU-GEI is an international multisite prospective study of participants at CHR referred from local mental health services. ALSPAC is a United Kingdom-based general population birth cohort. Included were EU-GEI participants who met CHR criteria at baseline and ALSPAC participants who did not report PEs at age 12 years. Data were analyzed from September 2018 to April 2020. Main Outcomes and Measures: In EU-GEI, transition status was assessed by the Comprehensive Assessment of At-Risk Mental States or contact with clinical services. In ALSPAC, PEs at age 18 years were assessed using the Psychosis-Like Symptoms Interview. Proteomic data were obtained from mass spectrometry of baseline plasma samples in EU-GEI and plasma samples at age 12 years in ALSPAC. Support vector machine learning algorithms were used to develop predictive models. Results: The EU-GEI subsample (133 participants at CHR (mean [SD] age, 22.6 [4.5] years; 68 [51.1%] male) comprised 49 (36.8%) who developed psychosis and 84 (63.2%) who did not. A model based on baseline clinical and proteomic data demonstrated excellent performance for prediction of transition outcome (area under the receiver operating characteristic curve [AUC], 0.95; positive predictive value [PPV], 75.0%; and negative predictive value [NPV], 98.6%). Functional analysis of differentially expressed proteins implicated the complement and coagulation cascade. A model based on the 10 most predictive proteins accurately predicted transition status in training (AUC, 0.99; PPV, 76.9%; and NPV, 100%) and test (AUC, 0.92; PPV, 81.8%; and NPV, 96.8%) data. The ALSPAC subsample (121 participants from the general population with plasma samples available at age 12 years (61 [50.4%] male) comprised 55 participants (45.5%) with PEs at age 18 years and 61 (50.4%) without PEs at age 18 years. A model using proteomic data at age 12 years predicted PEs at age 18 years, with an AUC of 0.74 (PPV, 67.8%; and NPV, 75.8%). Conclusions and Relevance: In individuals at risk of psychosis, proteomic biomarkers may contribute to individualized prognosis and stratification strategies. These findings implicate early dysregulation of the complement and coagulation cascade in the development of psychosis outcomes.

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TL;DR: In this article, a scoping review of literature between 1 January 2020 and 1 August 2021 was performed to synthesise evidence on the impact of the COVID-19 pandemic on vaccine hesitancy.
Abstract: Background: Vaccines have been contributing to eradicate or drastically reduce the incidence of common diseases. Simultaneously, vaccine hesitancy is considered among the top ten global health threats. The COVID-19 pandemic has caused a tremendous impact on health, economics, and society worldwide, while also reinforcing faulty beliefs about the necessity of vaccine programs as a whole. This study aims to synthesise evidence on the impact of the COVID-19 pandemic on vaccine hesitancy. Methods: A scoping review of literature between 1 January 2020 and 1 August 2021 was performed. Results: COVID-19 vaccine acceptance decreased from more than 70 to <50% in 8 months starting from January 2020. Healthcare professionals demonstrate higher rates of vaccine receptivity than the public, which was more influenced by (social) media. The circulation of misinformation was associated with increased fear of side effects related to COVID-19 vaccines. Regarding other vaccines coverage, parents' intentions to vaccinate their children against influenza increased 15.8% during the COVID-19 pandemic so far. Nonetheless, the number of vaccines administered decreased, influenced by factors like fear of being exposed to the virus at healthcare facilities and restrictions. Conclusions: Several efforts should be undertaken to improve vaccine acceptance and coverage now and beyond the pandemic to optimal population protection.

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TL;DR: In this article, a cross-sectional study of eligible adolescents and adults from the Africa Health Research Institute demographic surveillance area in the uMkhanyakude district of KwaZulu-Natal, South Africa was conducted to identify the prevalence and overlap of infectious and non-communicable diseases in such a population in rural South Africa.

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TL;DR: In this article, the influence of cancer on the systemic alteration of monocyte subset abundance and transcriptional profiles in the circulation has been revealed, exemplified by the influence that cancer can enhance the metastatic spread of primary cancers and may offer therapeutic opportunities.

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TL;DR: The research emphasises the importance of listening to community perspectives and accounting for context-specific realities to design locally appropriate and effective responses to COVID-19 communities require support with basic needs and reliable information to enable them to follow prevention measures Healthcare workers urgently need personal 3 protective equipment.
Abstract: Objective: To investigate community and health-care workers' perspectives on the coronavirus disease 2019 (COVID-19) pandemic and on early pandemic responses during the first 2 weeks of national lockdown in Zimbabwe. Methods: Rapid qualitative research was carried out between March and April 2020 via phone interviews with one representative from each of four community-based organizations and 16 health-care workers involved in a trial of community-based services for young people. In addition, information on COVID-19 was collected from social media platforms, news outlets and government announcements. Data were analysed thematically. Findings: Four themes emerged: (i) individuals were overloaded with information but lacked trusted sources, which resulted in widespread fear and unanswered questions; (ii) communities had limited ability to comply with prevention measures, such as social distancing, because access to long-term food supplies and water at home was limited and because income had to be earned daily; (iii) health-care workers perceived themselves to be vulnerable and undervalued because of a shortage of personal protective equipment and inadequate pay; and (iv) other health conditions were sidelined because resources were redirected, with potentially wide-reaching implications. Conclusion: It is important that prevention measures against COVID-19 are appropriate for the local context. In Zimbabwe, communities require support with basic needs and access to reliable information to enable them to follow prevention measures. In addition, health-care workers urgently need personal protective equipment and adequate salaries. Essential health-care services and medications for conditions other than COVID-19 must also continue to be provided to help reduce excess mortality and morbidity.

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TL;DR: The authors adapted the variant call format to store GWAS summary statistics (GWAS-VCF) and developed open-source tools to use this format in downstream analyses for GWAS analysis.
Abstract: GWAS summary statistics are fundamental for a variety of research applications yet no common storage format has been widely adopted. Existing tabular formats ambiguously or incompletely store information about genetic variants and associations, lack essential metadata and are typically not indexed yielding poor query performance and increasing the possibility of errors in data interpretation and post-GWAS analyses. To address these issues, we adapted the variant call format to store GWAS summary statistics (GWAS-VCF) and developed open-source tools to use this format in downstream analyses. We provide open access to over 10,000 complete GWAS summary datasets converted to this format ( https://gwas.mrcieu.ac.uk ).