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The University of Oxford, in collaboration with AstraZeneca plc, today announces interim trial data from its Phase III trials that show its candidate vaccine, ChAdOx1 nCoV-2019, is effective at preventing COVID-19 (SARS-CoV-2) and offers a high level of protection.
Perinatal outcomes after admission with COVID-19 in pregnancy: a UK national cohort study.
There are few population-based studies of sufficient size and follow-up duration to have reliably assessed perinatal outcomes for pregnant women hospitalised with SARS-CoV-2 infection. The United Kingdom Obstetric Surveillance System (UKOSS) covers all 194 consultant-led UK maternity units and included all pregnant women admitted to hospital with an ongoing SARS-CoV-2 infection. Here we show that in this large national cohort comprising two years' active surveillance over four SARS-CoV-2 variant periods and with near complete follow-up of pregnancy outcomes for 16,627 included women, severe perinatal outcomes were more common in women with moderate to severe COVID-19, during the delta dominant period and among unvaccinated women. We provide strong evidence to recommend continuous surveillance of pregnancy outcomes in future pandemics and to continue to recommend SARS-CoV-2 vaccination in pregnancy to protect both mothers and babies.
Preterm prelabour rupture of membranes before 23 weeks' gestation: prospective observational study.
ObjectiveTo describe perinatal and maternal outcomes of preterm prelabour rupture of membranes (PPROM) before 23 weeks' gestation in a national cohort.DesignProspective observational study.SettingNational population based cohort study with the UK Obstetric Surveillance System (UKOSS), a research infrastructure of all 194 obstetric units in the UK, 1 September 2019 to 28 February 2021.Participants326 women with singleton and 38 with multiple pregnancies with PPROM between 16+0 and 22+6 weeks+days' gestation.Main outcome measuresPerinatal outcomes of live birth, survival to discharge from hospital, and severe morbidity, defined as intraventricular haemorrhage grade 3 or 4, or requiring supplemental oxygen at 36 weeks' postmenstrual age, or both. Maternal outcomes were surgery for removal of the placenta, sepsis, admission to an intensive treatment unit, and death. Clinical data included rates of termination of pregnancy for medical reasons.ResultsPerinatal outcomes were calculated with all terminations of pregnancy for medical reasons excluded, and a worst-best range was calculated assuming that all terminations for medical reasons and those with missing data would have died (minimum value) or all would be liveborn (maximum value). For singleton pregnancies, the live birth rate was 44% (98/223), range 30-62% (98/326-201/326), perinatal survival to discharge from hospital was 26% (54/207), range 17-53% (54/326-173/326), and 18% (38/207), range 12-48% (38/326-157/326) of babies survived without severe morbidity. The rate of maternal sepsis was 12% (39/326) in singleton and 29% (11/38) in multiple pregnancies (P=0.004). Surgery for removal of the placenta was needed in 20% (65/326) and 16% (6/38) of singleton and twin pregnancies, respectively. Five women became severely unwell with sepsis; two died and another three required care in the intensive treatment unit.ConclusionsIn this study, 26% of women who had very early PPROM with expectant management had babies that survived to discharge from hospital. Morbidity and mortality rates were high for both mothers and neonates. Maternal sepsis is a considerable risk that needs more research. These data should be used in counselling families with PPROM before 23 weeks' gestation, and currently available guidelines should be updated accordingly.
Translational profiling of motor neurons with C9orf72 mutations under acute oxidative stress
Amyotrophic lateral sclerosis (ALS) is the most common adult-onset motor neuron disease (MND) with a median survival of 30 months from disease onset and no cure available. Mutations in the gene C9orf72-SMCR8 complex subunit (C9orf72) are the most common cause of ALS in populations of European genetic heritage. Previous studies suggest that RNA processing, global translation and stress granule (SG) dynamics are dysregulated in C9orf72-ALS, which might alter the profile of translating mRNAs (translatome) in motor neurons. To test this hypothesis, I employed translating ribosome affinity purification (TRAP) to obtain the parallel transcriptome and translatome of human induced pluripotent stem cell-derived motor neurons (iPSC-MNs) from patients with C9orf72 mutations and healthy controls. I examined their expression profiles both at baseline and after transient oxidative stress. While minimal differences were present in the transcriptome and translatome at baseline and immediately after stress, 68 differentially expressed genes (DEGs) were identified in the translatome 2 h after stress removal. Functional over-representation analysis showed that they were enriched in synaptic transmission, small GTPase-mediated signalling transduction, and neuron projection. Two of the downregulated DEGs, unc-13 homolog A (UNC13A) and purine rich element binding protein A (PURA), have been previously associated with ALS. Further characterisation of the acute stress response in iPSC-MNs revealed that transient oxidative stress exacerbated or induced some key molecular phenotypes related to C9orf72-ALS. Additionally, the mutant iPSC-MNs exhibited a gradual and persistent decrease in the signal of a cell viability assay, in contrast to the control group. No differences were found between the two groups in global translational activity or SG dynamics. Preliminary investigation into the subcellular distribution of UNC13A and PURA transcripts suggested potential dysregulation in nucleocytoplasmic redistribution and sequestration by SGs in C9orf72-ALS iPSC-MNs, although further experimentation is needed to reach a definitive conclusion.
Emerging variants develop total escape from potent monoclonal antibodies induced by BA.4/5 infection.
The rapid evolution of SARS-CoV-2 is driven in part by a need to evade the antibody response in the face of high levels of immunity. Here, we isolate spike (S) binding monoclonal antibodies (mAbs) from vaccinees who suffered vaccine break-through infections with Omicron sub lineages BA.4 or BA.5. Twenty eight potent antibodies are isolated and characterised functionally, and in some cases structurally. Since the emergence of BA.4/5, SARS-CoV-2 has continued to accrue mutations in the S protein, to understand this we characterize neutralization of a large panel of variants and demonstrate a steady attrition of neutralization by the panel of BA.4/5 mAbs culminating in total loss of function with recent XBB.1.5.70 variants containing the so-called 'FLip' mutations at positions 455 and 456. Interestingly, activity of some mAbs is regained on the recently reported variant BA.2.86.
A Report on the Safety of Acitretin Use in Renal Failure Patients on Hemodialysis
Abstract Acitretin, commonly used for severe psoriasis and keratinocyte carcinoma chemoprevention in high-risk patients, is contraindicated in patients with end stage renal disease on hemodialysis. However, these patients often lack medication choices and in certain clinical scenarios, the benefits of acitretin may outweigh the potential risks. We identified 24 end stage renal disease patients on HD taking acitretin from Duke and Vanderbilt University Medical Centers. While adverse effects were common, patients did not frequently discontinue the medication due to them. We also found no association between acitretin with hospital admissions or mortality. We lastly found statistically significant increases in ALP and total bilirubin when on acitretin and dialysis compared to baseline. However, there was no dose-dependency or temporal association with acitretin or hemodialysis initiation. Based off these preliminary findings, we find that acitretin may safely be used in patients receiving HD with close monitoring of ALP and bilirubin.
Crucial role of the transcription factors family activator protein 2 in cancer: current clue and views.
The transcription factor family activator protein 2 (TFAP2) is vital for regulating both embryonic and oncogenic development. The TFAP2 family consists of five DNA-binding proteins, including TFAP2A, TFAP2B, TFAP2C, TFAP2D and TFAP2E. The importance of TFAP2 in tumor biology is becoming more widely recognized. While TFAP2D is not well studied, here, we mainly focus on the other four TFAP2 members. As a transcription factor, TFAP2 regulates the downstream targets directly by binding to their regulatory region. In addition, the regulation of downstream targets by epigenetic modification, posttranslational regulation, and interaction with noncoding RNA have also been identified. According to the pathways in which the downstream targets are involved in, the regulatory effects of TFAP2 on tumorigenesis are generally summarized as follows: stemness and EMT, interaction between TFAP2 and tumor microenvironment, cell cycle and DNA damage repair, ER- and ERBB2-related signaling pathway, ferroptosis and therapeutic response. Moreover, the factors that affect TFAP2 expression in oncogenesis are also summarized. Here, we review and discuss the most recent studies on TFAP2 and its effects on carcinogenesis and regulatory mechanisms.
USP28 deletion and small-molecule inhibition destabilizes c-MYC and elicits regression of squamous cell lung carcinoma
Lung squamous cell carcinoma (LSCC) is a considerable global health burden, with an incidence of over 600,000 cases per year. Treatment options are limited, and patient’s 5-year survival rate is less than 5%. The ubiquitin-specific protease 28 (USP28) has been implicated in tumourigenesis through its stabilization of the oncoproteins c-MYC, c-JUN, and Δp63. Here, we show that genetic inactivation of Usp28-induced regression of established murine LSCC lung tumours. We developed a small molecule that inhibits USP28 activity in the low nanomole range. While displaying cross-reactivity against the closest homologue USP25, this inhibitor showed a high degree of selectivity over other deubiquitinases. USP28 inhibitor treatment resulted in a dramatic decrease in c-MYC, c-JUN, and Δp63 proteins levels and consequently induced substantial regression of autochthonous murine LSCC tumours and human LSCC xenografts, thereby phenocopying the effect observed by genetic deletion. Thus, USP28 may represent a promising therapeutic target for the treatment of squamous cell lung carcinoma.
Neutrophilia, lymphopenia and myeloid dysfunction: a living review of the quantitative changes to innate and adaptive immune cells which define COVID-19 pathology
Abstract Destabilization of balanced immune cell numbers and frequencies is a common feature of viral infections. This occurs due to, and further enhances, viral immune evasion and survival. Since the discovery of the Severe Acute Respiratory Syndrome coronavirus 2 (SARS-CoV-2), which manifests in coronavirus disease 2019 (COVID-19), a great number of studies have described the association between this virus and pathologically increased or decreased immune cell counts. In this review, we consider the absolute and relative changes to innate and adaptive immune cell numbers, in COVID-19. In severe disease particularly, neutrophils are increased, which can lead to inflammation and tissue damage. Dysregulation of other granulocytes, basophils and eosinophils represents an unusual COVID-19 phenomenon. Contrastingly, the impact on the different types of monocytes leans more strongly to an altered phenotype, e.g. HLA-DR expression, rather than numerical changes. However, it is the adaptive immune response that bears the most profound impact of SARS-CoV-2 infection. T cell lymphopenia correlates with increased risk of intensive care unit admission and death; therefore, this parameter is particularly important for clinical decision-making. Mild and severe diseases differ in the rate of immune cell counts returning to normal levels post disease. Tracking the recovery trajectories of various immune cell counts may also have implications for long-term COVID-19 monitoring. This review represents a snapshot of our current knowledge, showing that much has been achieved in a short period of time. Alterations in counts of distinct immune cells represent an accessible metric to inform patient care decisions or predict disease outcomes.
T cell phenotypes in COVID-19 - a living review
Abstract COVID-19 is characterized by profound lymphopenia in the peripheral blood, and the remaining T cells display altered phenotypes, characterized by a spectrum of activation and exhaustion. However, antigen-specific T cell responses are emerging as a crucial mechanism for both clearance of the virus and as the most likely route to long-lasting immune memory that would protect against re-infection. Therefore, T cell responses are also of considerable interest in vaccine development. Furthermore, persistent alterations in T cell subset composition and function post-infection have important implications for patients’ long-term immune function. In this review, we examine T cell phenotypes, including those of innate T cells, in both peripheral blood and lungs, and consider how key markers of activation and exhaustion correlate with, and may be able to predict, disease severity. We focus on SARS-CoV-2-specific T cells to elucidate markers that may indicate formation of antigen-specific T cell memory. We also examine peripheral T cell phenotypes in recovery and the likelihood of long-lasting immune disruption. Finally, we discuss T cell phenotypes in the lung as important drivers of both virus clearance and tissue damage. As our knowledge of the adaptive immune response to COVID-19 rapidly evolves, it has become clear that while some areas of the T cell response have been investigated in some detail, others, such as the T cell response in children remain largely unexplored. Therefore, this review will also highlight areas where T cell phenotypes require urgent characterisation.
Dietary n-3 polyunsaturated fatty acids alter the number, fatty acid profile and coagulatory activity of circulating and platelet-derived extracellular vesicles: a randomized, controlled crossover trial.
BackgroundExtracellular vesicles (EVs) are proposed to play a role in the development of cardiovascular diseases (CVDs) and are considered emerging markers of CVDs. n-3 PUFAs are abundant in oily fish and fish oil and are reported to reduce CVD risk, but there has been little research to date examining the effects of n-3 PUFAs on the generation and function of EVs.ObjectivesWe aimed to investigate the effects of fish oil supplementation on the number, generation, and function of EVs in subjects with moderate risk of CVDs.MethodsA total of 40 participants with moderate risk of CVDs were supplemented with capsules containing either fish oil (1.9 g/d n-3 PUFAs) or control oil (high-oleic safflower oil) for 12 wk in a randomized, double-blind, placebo-controlled crossover intervention study. The effects of fish oil supplementation on conventional CVD and thrombogenic risk markers were measured, along with the number and fatty acid composition of circulating and platelet-derived EVs (PDEVs). PDEV proteome profiles were evaluated, and their impact on coagulation was assessed using assays including fibrin clot formation, thrombin generation, fibrinolysis, and ex vivo thrombus formation.Resultsn-3 PUFAs decreased the numbers of circulating EVs by 27%, doubled their n-3 PUFA content, and reduced their capacity to support thrombin generation by >20% in subjects at moderate risk of CVDs. EVs derived from n-3 PUFA-enriched platelets in vitro also resulted in lower thrombin generation but did not alter thrombus formation in a whole blood ex vivo assay.ConclusionsDietary n-3 PUFAs alter the number, composition, and function of EVs, reducing their coagulatory activity. This study provides clear evidence that EVs support thrombin generation and that this EV-dependent thrombin generation is reduced by n-3 PUFAs, which has implications for prevention and treatment of thrombosis.Clinical trial registryThis trial was registered at clinicaltrials.gov as NCT03203512.
Type I interferon regulation by USP18 is a key vulnerability in cancer
Precise regulation of Type I interferon signaling is crucial for combating infection and cancer while avoiding autoimmunity. Type I interferon signaling is negatively regulated by USP18. USP18 cleaves ISG15, an interferon-induced ubiquitin-like modification, via its canonical catalytic function, and inhibits Type I interferon receptor activity through its scaffold role. USP18 loss-of-function dramatically impacts immune regulation, pathogen susceptibility, and tumor growth. However, prior studies have reached conflicting conclusions regarding the relative importance of catalytic versus scaffold function. Here, we develop biochemical and cellular methods to systematically define the physiological role of USP18. By comparing a patient-derived mutation impairing scaffold function (I60N) to a mutation disrupting catalytic activity (C64S), we demonstrate that scaffold function is critical for cancer cell vulnerability to Type I interferon. Surprisingly, we discovered that human USP18 exhibits minimal catalytic activity, in stark contrast to mouse USP18. These findings resolve human USP18's mechanism-of-action and enable USP18-targeted therapeutics.
Semmaphorin 3 A causes immune suppression by inducing cytoskeletal paralysis in tumour-specific CD8+ T cells.
Semaphorin-3A (SEMA3A) functions as a chemorepulsive signal during development and can affect T cells by altering their filamentous actin (F-actin) cytoskeleton. The exact extent of these effects on tumour-specific T cells are not completely understood. Here we demonstrate that Neuropilin-1 (NRP1) and Plexin-A1 and Plexin-A4 are upregulated on stimulated CD8+ T cells, allowing tumour-derived SEMA3A to inhibit T cell migration and assembly of the immunological synapse. Deletion of NRP1 in both CD4+ and CD8+ T cells enhance CD8+ T-cell infiltration into tumours and restricted tumour growth in animal models. Conversely, over-expression of SEMA3A inhibit CD8+ T-cell infiltration. We further show that SEMA3A affects CD8+ T cell F-actin, leading to inhibition of immune synapse formation and motility. Examining a clear cell renal cell carcinoma patient cohort, we find that SEMA3A expression is associated with reduced survival, and that T-cells appear trapped in SEMA3A rich regions. Our study establishes SEMA3A as an inhibitor of effector CD8+ T cell tumour infiltration, suggesting that blocking NRP1 could improve T cell function in tumours.