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1.
F1000Res ; 13: 679, 2024.
Article de Anglais | MEDLINE | ID: mdl-39193510

RÉSUMÉ

Sponges (Phylum Porifera) are aquatic sessile metazoans found worldwide in marine and freshwater environments. They are significant in the animal tree of life as one of the earliest-branching metazoan lineages and as filter feeders play crucial ecological roles, particularly in coral reefs, but are susceptible to the effects of climate change. In the face of the current biodiversity crisis, genomic data is crucial for species conservation efforts and predicting their evolutionary potential in response to environmental changes. However, there is a limited availability of culturable sponge species with annotated high-quality genomes to further comprehensive insights into animal evolution, function, and their response to the ongoing global change. Despite the publication of a few high-quality annotated sponge genomes, there remains a gap in resources for culturable sponge species. To address this gap, we provide high quality draft genomes of the two congeneric aquarium species Tethya wilhelma and Tethya minuta, small ball-shaped demosponges that are easily maintained long-term in ex situ culture. As such, they offer promising opportunities as laboratory models to contribute to advancing our understanding of sponge biology and provide valuable resources for studying animal evolution, function, and responses to environmental challenges.


Sujet(s)
Génome , Porifera , Porifera/génétique , Animaux , Phylogenèse
2.
Virus Res ; 346: 199404, 2024 08.
Article de Anglais | MEDLINE | ID: mdl-38782262

RÉSUMÉ

Parapoxviruses (PPV) of animals are spread worldwide. While the Orf virus (ORFV) species is a molecularly well-characterized prototype pathogen of small ruminants, the genomes of virus species affecting large ruminants, namely Bovine papular stomatitis virus (BPSV) and Pseudocowpox virus (PCPV), are less well known. Using Nanopore sequencing we retrospectively show the whole genome sequences (WGS) of six BPSV, three PCPV isolates and an attenuated ORFV strain, originating from different geographic locations. A phylogenetic tree shows that the de novo assembled genomes belong to PPV species including WGS of reference PPV. Remarkably, Nanopore sequencing allowed the molecular resolution of inverted terminal repeats (ITR) and the hairpin loop within the de novo assembled WGS. Additionally, peculiarities regarding map location of two genes and the heterogeneity of a genomic region were noted. Details for the molecular variability of an interferon response modulatory gene (ORF116) and the PCPV specificity of gene 073.5 are reported. In summary, WGS gained by Nanopore sequencing allowed analysis of complete PPV genomes and confident virus species attribution within a phylogenetic tree avoiding uncertainty of limited gene-based diagnostics. Nanopore-based WGS provides robust comparison of PPV genomes and reliable identity determination of new Poxviruses.


Sujet(s)
Maladies des bovins , Génome viral , Parapoxvirus , Phylogenèse , Infections à Poxviridae , Séquençage du génome entier , Animaux , Bovins , Parapoxvirus/génétique , Parapoxvirus/classification , Parapoxvirus/isolement et purification , Infections à Poxviridae/virologie , Infections à Poxviridae/médecine vétérinaire , Études rétrospectives , Maladies des bovins/virologie , Séquençage par nanopores/méthodes , ADN viral/génétique
3.
Nat Commun ; 15(1): 3813, 2024 May 07.
Article de Anglais | MEDLINE | ID: mdl-38714682

RÉSUMÉ

Innate antiviral factors are essential for effective defense against viral pathogens. However, the identity of major restriction mechanisms remains elusive. Current approaches to discover antiviral factors usually focus on the initial steps of viral replication and are limited to a single round of infection. Here, we engineered libraries of >1500 replication-competent HIV-1 constructs each expressing a single gRNAs to target >500 cellular genes for virus-driven discovery of antiviral factors. Passaging in CD4+ T cells robustly enriched HIV-1 encoding sgRNAs against GRN, CIITA, EHMT2, CEACAM3, CC2D1B and RHOA by >50-fold. Using an HIV-1 library lacking the accessory nef gene, we identified IFI16 as a Nef target. Functional analyses in cell lines and primary CD4+ T cells support that the HIV-driven CRISPR screen identified restriction factors targeting virus entry, transcription, release and infectivity. Our HIV-guided CRISPR technique enables sensitive discovery of physiologically relevant cellular defense factors throughout the entire viral replication cycle.


Sujet(s)
Lymphocytes T CD4+ , VIH-1 (Virus de l'Immunodéficience Humaine de type 1) , Réplication virale , Produits du gène nef du virus de l'immunodéficience humaine , Humains , VIH-1 (Virus de l'Immunodéficience Humaine de type 1)/génétique , VIH-1 (Virus de l'Immunodéficience Humaine de type 1)/physiologie , Réplication virale/génétique , Produits du gène nef du virus de l'immunodéficience humaine/génétique , Produits du gène nef du virus de l'immunodéficience humaine/métabolisme , Lymphocytes T CD4+/virologie , Lymphocytes T CD4+/métabolisme , Lymphocytes T CD4+/immunologie , Cellules HEK293 , Systèmes CRISPR-Cas , Infections à VIH/virologie , Infections à VIH/génétique , Infections à VIH/immunologie , RNA, Guide, CRISPR-Cas Systems/génétique , RNA, Guide, CRISPR-Cas Systems/métabolisme , Phosphoprotéines/métabolisme , Phosphoprotéines/génétique , Protéine G RhoA/métabolisme , Protéine G RhoA/génétique , Clustered regularly interspaced short palindromic repeats/génétique , Pénétration virale
4.
J Autoimmun ; 146: 103234, 2024 Jun.
Article de Anglais | MEDLINE | ID: mdl-38663202

RÉSUMÉ

Narcolepsy is a rare cause of hypersomnolence and may be associated or not with cataplexy, i.e. sudden muscle weakness. These forms are designated narcolepsy-type 1 (NT1) and -type 2 (NT2), respectively. Notable characteristics of narcolepsy are that most patients carry the HLA-DQB1*06:02 allele and NT1-patients have strongly decreased levels of hypocretin-1 (synonym orexin-A) in the cerebrospinal fluid (CSF). The pathogenesis of narcolepsy is still not completely understood but the strong HLA-bias and increased frequencies of CD4+ T cells reactive to hypocretin in the peripheral blood suggest autoimmune processes in the hypothalamus. Here we analyzed the transcriptomes of CSF-cells from twelve NT1 and two NT2 patients by single cell RNAseq (scRNAseq). As controls, we used CSF cells from patients with multiple sclerosis, radiologically isolated syndrome, and idiopathic intracranial hypertension. From 27,255 CSF cells, we identified 20 clusters of different cell types and found significant differences in three CD4+ T cell and one monocyte clusters between narcolepsy and multiple sclerosis patients. Over 1000 genes were differentially regulated between patients with NT1 and other diseases. Surprisingly, the most strongly upregulated genes in narcolepsy patients as compared to controls were coding for the genome-encoded MTRNR2L12 and MTRNR2L8 peptides, which are homologous to the mitochondria-encoded HUMANIN peptide that is known playing a role in other neurological diseases including Alzheimer's disease.


Sujet(s)
Narcolepsie , Analyse sur cellule unique , Transcriptome , Humains , Narcolepsie/génétique , Narcolepsie/liquide cérébrospinal , Mâle , Femelle , Adulte , Orexines/liquide cérébrospinal , Orexines/génétique , Analyse de profil d'expression de gènes , Lymphocytes T CD4+/immunologie , Lymphocytes T CD4+/métabolisme , Chaines bêta des antigènes HLA-DQ/génétique , Adulte d'âge moyen , Jeune adulte
5.
Sci Adv ; 10(15): eadj0954, 2024 Apr 12.
Article de Anglais | MEDLINE | ID: mdl-38608027

RÉSUMÉ

Occupied between ~10,300 and 9300 years ago, the Pre-Pottery Neolithic site of Asikli Höyük in Central Anatolia went through early phases of sheep domestication. Analysis of 629 mitochondrial genomes from this and numerous sites in Anatolia, southwest Asia, Europe, and Africa produced a phylogenetic tree with excessive coalescences (nodes) around the Neolithic, a potential signature of a domestication bottleneck. This is consistent with archeological evidence of sheep management at Asikli Höyük which transitioned from residential stabling to open pasturing over a millennium of site occupation. However, unexpectedly, we detected high genetic diversity throughout Asikli Höyük's occupation rather than a bottleneck. Instead, we detected a tenfold demographic bottleneck later in the Neolithic, which caused the fixation of mitochondrial haplogroup B in southwestern Anatolia. The mitochondrial genetic makeup that emerged was carried from the core region of early Neolithic sheep management into Europe and dominates the matrilineal diversity of both its ancient and the billion-strong modern sheep populations.


Sujet(s)
Génome mitochondrial , Animaux , Ovis/génétique , Phylogenèse , Ovis aries/génétique , Turquie , Afrique
6.
Nat Commun ; 15(1): 3463, 2024 Apr 24.
Article de Anglais | MEDLINE | ID: mdl-38658564

RÉSUMÉ

Under-reporting of COVID-19 and the limited information about circulating SARS-CoV-2 variants remain major challenges for many African countries. We analyzed SARS-CoV-2 infection dynamics in Addis Ababa and Jimma, Ethiopia, focusing on reinfection, immunity, and vaccination effects. We conducted an antibody serology study spanning August 2020 to July 2022 with five rounds of data collection across a population of 4723, sequenced PCR-test positive samples, used available test positivity rates, and constructed two mathematical models integrating this data. A multivariant model explores variant dynamics identifying wildtype, alpha, delta, and omicron BA.4/5 as key variants in the study population, and cross-immunity between variants, revealing risk reductions between 24% and 69%. An antibody-level model predicts slow decay leading to sustained high antibody levels. Retrospectively, increased early vaccination might have substantially reduced infections during the delta and omicron waves in the considered group of individuals, though further vaccination now seems less impactful.


Sujet(s)
Anticorps antiviraux , COVID-19 , SARS-CoV-2 , Humains , Éthiopie/épidémiologie , COVID-19/épidémiologie , COVID-19/immunologie , COVID-19/virologie , COVID-19/prévention et contrôle , SARS-CoV-2/immunologie , SARS-CoV-2/génétique , Anticorps antiviraux/sang , Anticorps antiviraux/immunologie , Études séroépidémiologiques , Mâle , Adulte , Femelle , Adolescent , Jeune adulte , Adulte d'âge moyen , Enfant , Sujet âgé , Enfant d'âge préscolaire , Vaccination , Vaccins contre la COVID-19/immunologie , Études rétrospectives , Réinfection/épidémiologie , Réinfection/immunologie , Réinfection/virologie
7.
Sci Immunol ; 9(93): eadd4818, 2024 Mar.
Article de Anglais | MEDLINE | ID: mdl-38427718

RÉSUMÉ

T follicular helper (TFH) cells are essential for effective antibody responses, but deciphering the intrinsic wiring of mouse TFH cells has long been hampered by the lack of a reliable protocol for their generation in vitro. We report that transforming growth factor-ß (TGF-ß) induces robust expression of TFH hallmark molecules CXCR5 and Bcl6 in activated mouse CD4+ T cells in vitro. TGF-ß-induced mouse CXCR5+ TFH cells are phenotypically, transcriptionally, and functionally similar to in vivo-generated TFH cells and provide critical help to B cells. The study further reveals that TGF-ß-induced CXCR5 expression is independent of Bcl6 but requires the transcription factor c-Maf. Classical TGF-ß-containing T helper 17 (TH17)-inducing conditions also yield separate CXCR5+ and IL-17A-producing cells, highlighting shared and distinct cell fate trajectories of TFH and TH17 cells. We demonstrate that excess IL-2 in high-density T cell cultures interferes with the TGF-ß-induced TFH cell program, that TFH and TH17 cells share a common developmental stage, and that c-Maf acts as a switch factor for TFH versus TH17 cell fates in TGF-ß-rich environments in vitro and in vivo.


Sujet(s)
Lymphocytes T auxiliaires , Facteur de croissance transformant bêta , Animaux , Souris , Facteur de croissance transformant bêta/métabolisme , Lymphocytes B , Lymphocytes T CD4+ , Différenciation cellulaire , Protéines proto-oncogènes c-maf/métabolisme
8.
Arch Orthop Trauma Surg ; 144(5): 1969-1976, 2024 May.
Article de Anglais | MEDLINE | ID: mdl-38554204

RÉSUMÉ

PURPOSE: This study presents an abnormality of the musculus rectus capitis posterior minor (RCPmi) as a new etiological factor for nontraumatic sagittal plane instability in the C0-C1-C2-complex, with a focus on identifying the absence or atrophy of RCPmi on both sides. METHODS: A 36-year-old male patient presented with recurring neck pain (VAS 8/10) and tingling paresthesia in the entire left hand over a six-month period, without significant neurological deficits. Radiated arm pain was not reported. Imaging examinations revealed sagittal plane instability in the C0-C1-C2-complex, spinal canal stenosis (SCS), and myelopathy at the C1 level. Subsequently, a dorsal C0-1 reposition and fusion with laminectomy were performed. RESULTS: The congenital absence or atrophy of RCPmi, leading to the lack of cephalad-rearward traction on the C1-tuberculum-posterius, induced a developmental failure of the C1 posterior arch. Consequently, the oblate-shaped C1 posterior arch lost support from the underlying C2 posterior arch and the necessary cephalad-rearward traction throughout the patient's 36-year life. This gradual loss of support and traction caused the C1 posterior arch to shift gradually to the anterior side of the C2 posterior arch, resulting in a rotational subluxation centered on the C0/1 joints in the sagittal plane. Ultimately, this led to SCS and myelopathy. Traumatic factors were ruled out from birth to the present, and typical degenerative changes were not found in the upper cervical spine, neck muscles, and ligaments. CONCLUSION: In this case, we not only report the atrophy or absence of RCPmi as a new etiological factor for nontraumatic sagittal plane instability in the C0-C1-C2-complex but also discovered a new function of RCPmi. The cephalad-rearward traction exerted by RCPmi on the C1 posterior arch is essential for the development of a normal C1 anterior-posterior diameter.


Sujet(s)
Vertèbres cervicales , Instabilité articulaire , Humains , Mâle , Adulte , Instabilité articulaire/chirurgie , Instabilité articulaire/étiologie , Instabilité articulaire/imagerie diagnostique , Vertèbres cervicales/imagerie diagnostique , Vertèbres cervicales/chirurgie , Articulation atlantoaxoïdienne/imagerie diagnostique , Articulation atlantoaxoïdienne/chirurgie , Arthrodèse vertébrale/méthodes
9.
Infection ; 2023 Nov 03.
Article de Anglais | MEDLINE | ID: mdl-37922037

RÉSUMÉ

PURPOSE: Lung transplant recipients are at increased risk of severe disease following infection with severe acute respiratory syndrome coronavirus type 2 (SARS-CoV-2) due to high-dose immunosuppressive drugs and the lung is the main organ affected by Coronavirus disease 2019 (COVID-19). Several studies have confirmed increased SARS-CoV-2-related mortality and morbidity in patients living with lung allografts; however, detailed immunological studies of patients with SARS-CoV-2 infection in the early phase following transplantation remain scarce. METHODS: We investigated patients who were infected with SARS-CoV-2 in the early phase (18-103 days) after receiving double-lung allografts (n = 4, LuTx) in comparison to immunocompetent patients who had not received solid organ transplants (n = 88, noTx). We analyzed SARS-CoV-2-specific antibody responses against the SARS-CoV-2 spike and nucleocapsid proteins using enzyme-linked immunosorbent assays (ELISA), chemiluminescence immunoassays (CLIA), and immunoblot assays. T cell responses were investigated using Elispot assays. RESULTS: One LuTx patient suffered from persistent infection with fatal outcome 122 days post-infection despite multiple interventions including remdesivir, convalescent plasma, and the monoclonal antibody bamlanivimab. Two patients experienced clinically mild disease with prolonged viral shedding (47 and 79 days), and one patient remained asymptomatic. Antibody and T cell responses were significantly reduced or undetectable in all LuTx patients compared to noTx patients. CONCLUSION: Patients in the early phase following lung allograft transplantation are vulnerable to infection with SARS-CoV-2 due to impaired immune responses. This patient population should be vaccinated before LuTx, protected from infection post-LuTx, and in case of infection treated generously with currently available interventions.

10.
Front Cell Dev Biol ; 11: 1265407, 2023.
Article de Anglais | MEDLINE | ID: mdl-37860816

RÉSUMÉ

Abnormalities are indispensable for studying normal biological processes and mechanisms. In the present work, we draw attention to the remarkable phenomenon of a perpetually and robustly upregulated gene, the thyroglobulin gene (Tg). The gene is expressed in the thyroid gland and, as it has been recently demonstrated, forms so-called transcription loops, easily observable by light microscopy. Using this feature, we show that Tg is expressed at a high level from the moment a thyroid cell acquires its identity and both alleles remain highly active over the entire life of the cell, i.e., for months or years depending on the species. We demonstrate that this high upregulation is characteristic of thyroglobulin genes in all major vertebrate groups. We provide evidence that Tg is not influenced by the thyroid hormone status, does not oscillate round the clock and is expressed during both the exocrine and endocrine phases of thyrocyte activity. We conclude that the thyroglobulin gene represents a unique and valuable model to study the maintenance of a high transcriptional upregulation.

11.
Hemasphere ; 7(10): e958, 2023 Oct.
Article de Anglais | MEDLINE | ID: mdl-37841755

RÉSUMÉ

Activating colony-stimulating factor-3 receptor gene (CSF3R) mutations are recurrent in acute myeloid leukemia (AML) with t(8;21) translocation. However, the nature of oncogenic collaboration between alterations of CSF3R and the t(8;21) associated RUNX1-RUNX1T1 fusion remains unclear. In CD34+ hematopoietic stem and progenitor cells from healthy donors, double oncogene expression led to a clonal advantage, increased self-renewal potential, and blast-like morphology and distinct immunophenotype. Gene expression profiling revealed hedgehog signaling as a potential mechanism, with upregulation of GLI2 constituting a putative pharmacological target. Both primary hematopoietic cells and the t(8;21) positive AML cell line SKNO-1 showed increased sensitivity to the GLI inhibitor GANT61 when expressing CSF3R T618I. Our findings suggest that during leukemogenesis, the RUNX1-RUNXT1 fusion and CSF3R mutation act in a synergistic manner to alter hedgehog signaling, which can be exploited therapeutically.

12.
Med Microbiol Immunol ; 212(5): 323-337, 2023 Oct.
Article de Anglais | MEDLINE | ID: mdl-37561225

RÉSUMÉ

Since late 2021, the variant landscape of the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has been dominated by the variant of concern (VoC) Omicron and its sublineages. We and others have shown that the detection of Omicron-BA.1 and -BA.2-positive respiratory specimens by rapid antigen tests (RATs) is impaired compared to Delta VoC-containing samples. Here, in a single-center retrospective laboratory study, we evaluated the performance of ten most commonly used RATs for the detection of Omicron-BA.4 and -BA.5 infections. We used 171 respiratory swab specimens from SARS-CoV-2 RNA-positive patients, of which 71 were classified as BA.4 and 100 as BA.5. All swabs were collected between July and September 2022. 50 SARS-CoV-2 PCR-negative samples from healthy individuals, collected in October 2022, showed high specificity in 9 out of 10 RATs. When assessing analytical sensitivity using clinical specimens, the 50% limit of detection (LoD50) ranged from 7.6 × 104 to 3.3 × 106 RNA copies subjected to the RATs for BA.4 compared to 6.8 × 104 to 3.0 × 106 for BA.5. Overall, intra-assay differences for the detection of these two Omicron subvariants were not significant for both respiratory swabs and tissue culture-expanded virus isolates. In contrast, marked heterogeneity was observed among the ten RATs: to be positive in these point-of-care tests, up to 443-fold (BA.4) and up to 56-fold (BA.5) higher viral loads were required for the worst performing RAT compared to the best performing RAT. True-positive rates for Omicron-BA.4- or -BA.5-containing specimens in the highest viral load category (Ct values < 25) ranged from 94.3 to 34.3%, dropping to 25.6 to 0% for samples with intermediate Ct values (25-30). We conclude that the high heterogeneity in the performance of commonly used RATs remains a challenge for the general public to obtain reliable results in the evolving Omicron subvariant-driven pandemic.


Sujet(s)
COVID-19 , SARS-CoV-2 , Humains , ARN viral , Études rétrospectives , COVID-19/diagnostic , Pandémies
13.
Med Microbiol Immunol ; 212(5): 307-322, 2023 Oct.
Article de Anglais | MEDLINE | ID: mdl-37561226

RÉSUMÉ

Diagnostic tests for direct pathogen detection have been instrumental to contain the severe acute respiratory syndrome coronavirus type 2 (SARS-CoV-2) pandemic. Automated, quantitative, laboratory-based nucleocapsid antigen (Ag) tests for SARS-CoV-2 have been launched alongside nucleic acid-based test systems and point-of-care (POC) lateral-flow Ag tests. Here, we evaluated four commercial Ag tests on automated platforms for the detection of different sublineages of the SARS-CoV-2 Omicron variant of concern (VoC) (B.1.1.529) in comparison with "non-Omicron" VoCs. A total of 203 Omicron PCR-positive respiratory swabs (53 BA.1, 48 BA.2, 23 BQ.1, 39 XBB.1.5 and 40 other subvariants) from the period February to March 2022 and from March 2023 were examined. In addition, tissue culture-expanded clinical isolates of Delta (B.1.617.2), Omicron-BA.1, -BF.7, -BN.1 and -BQ.1 were studied. These results were compared to previously reported data from 107 clinical "non-Omicron" samples from the end of the second pandemic wave (February to March 2021) as well as cell culture-derived samples of wildtype (wt) EU-1 (B.1.177), Alpha VoC (B.1.1.7) and Beta VoC (B.1.351)). All four commercial Ag tests were able to detect at least 90.9% of Omicron-containing samples with high viral loads (Ct < 25). The rates of true-positive test results for BA.1/BA.2-positive samples with intermediate viral loads (Ct 25-30) ranged between 6.7% and 100.0%, while they dropped to 0 to 15.4% for samples with low Ct values (> 30). This heterogeneity was reflected also by the tests' 50%-limit of detection (LoD50) values ranging from 44,444 to 1,866,900 Geq/ml. Respiratory samples containing Omicron-BQ.1/XBB.1.5 or other Omicron subvariants that emerged in 2023 were detected with enormous heterogeneity (0 to 100%) for the intermediate and low viral load ranges with LoD50 values between 23,019 and 1,152,048 Geq/ml. In contrast, detection of "non-Omicron" samples was more sensitive, scoring positive in 35 to 100% for the intermediate and 1.3 to 32.9% of cases for the low viral loads, respectively, corresponding to LoD50 values ranging from 6181 to 749,792 Geq/ml. All four assays detected cell culture-expanded VoCs Alpha, Beta, Delta and Omicron subvariants carrying up to six amino acid mutations in the nucleocapsid protein with sensitivities comparable to the non-VoC EU-1. Overall, automated quantitative SARS-CoV-2 Ag assays are not more sensitive than standard rapid antigen tests used in POC settings and show a high heterogeneity in performance for VoC recognition. The best of these automated Ag tests may have the potential to complement nucleic acid-based assays for SARS-CoV-2 diagnostics in settings not primarily focused on the protection of vulnerable groups. In light of the constant emergence of new Omicron subvariants and recombinants, most recently the XBB lineage, these tests' performance must be regularly re-evaluated, especially when new VoCs carry mutations in the nucleocapsid protein or immunological and clinical parameters change.


Sujet(s)
COVID-19 , Acides nucléiques , Humains , SARS-CoV-2/génétique , COVID-19/diagnostic , Protéines nucléocapside
14.
Sci Total Environ ; 903: 166540, 2023 Dec 10.
Article de Anglais | MEDLINE | ID: mdl-37634730

RÉSUMÉ

Wastewater-based SARS-CoV-2 epidemiology (WBE) has proven as an excellent tool to monitor pandemic dynamics supporting individual testing strategies. WBE can also be used as an early warning system for monitoring the emergence of novel pathogens or viral variants. However, for a timely transmission of results, sophisticated sample logistics and analytics performed in decentralized laboratories close to the sampling sites are required. Since multiple decentralized laboratories commonly use custom in-house workflows for sample purification and PCR-analysis, comparative quality control of the analytical procedures is essential to report reliable and comparable results. In this study, we performed an interlaboratory comparison at laboratories specialized for PCR and high-throughput-sequencing (HTS)-based WBE analysis. Frozen reserve samples from low COVID-19 incidence periods were spiked with different inactivated authentic SARS-CoV-2 variants in graduated concentrations and ratios. Samples were sent to the participating laboratories for analysis using laboratory specific methods and the reported viral genome copy numbers and the detection of viral variants were compared with the expected values. All PCR-laboratories reported SARS-CoV-2 genome copy equivalents (GCE) for all spiked samples with a mean intra- and inter-laboratory variability of 19 % and 104 %, respectively, largely reproducing the spike-in scheme. PCR-based genotyping was, in dependence of the underlying PCR-assay performance, able to predict the relative amount of variant specific substitutions even in samples with low spike-in amount. The identification of variants by HTS, however, required >100 copies/ml wastewater and had limited predictive value when analyzing at a genome coverage below 60 %. This interlaboratory test demonstrates that despite highly heterogeneous isolation and analysis procedures, overall SARS-CoV-2 GCE and mutations were determined accurately. Hence, decentralized SARS-CoV-2 wastewater monitoring is feasible to generate comparable analysis results. However, since not all assays detected the correct variant, prior evaluation of PCR and sequencing workflows as well as sustained quality control such as interlaboratory comparisons are mandatory for correct variant detection.

15.
EMBO Rep ; 24(9): e56150, 2023 09 06.
Article de Anglais | MEDLINE | ID: mdl-37424514

RÉSUMÉ

The largest subunit of RNA polymerase (Pol) II harbors an evolutionarily conserved C-terminal domain (CTD), composed of heptapeptide repeats, central to the transcriptional process. Here, we analyze the transcriptional phenotypes of a CTD-Δ5 mutant that carries a large CTD truncation in human cells. Our data show that this mutant can transcribe genes in living cells but displays a pervasive phenotype with impaired termination, similar to but more severe than previously characterized mutations of CTD tyrosine residues. The CTD-Δ5 mutant does not interact with the Mediator and Integrator complexes involved in the activation of transcription and processing of RNAs. Examination of long-distance interactions and CTCF-binding patterns in CTD-Δ5 mutant cells reveals no changes in TAD domains or borders. Our data demonstrate that the CTD is largely dispensable for the act of transcription in living cells. We propose a model in which CTD-depleted Pol II has a lower entry rate onto DNA but becomes pervasive once engaged in transcription, resulting in a defect in termination.


Sujet(s)
RNA polymerase II , Transcription génétique , Humains , RNA polymerase II/métabolisme , Noyau de la cellule/métabolisme , Mutation , Phosphorylation
16.
Neurology ; 101(9): e933-e939, 2023 08 29.
Article de Anglais | MEDLINE | ID: mdl-37407270

RÉSUMÉ

BACKGROUND OBJECTIVES: It is unclear whether IV thrombolysis (IVT) outperforms early dual antiplatelet therapy (DAPT) in the acute setting of mild ischemic stroke. The aim of this study was to compare the early safety and efficacy of IVT with that of DAPT. METHODS: Data of mild noncardioembolic stroke patients with admission NIH Stroke Scale (NIHSS) score ≤3 who received IVT or early DAPT in the period 2018-2021 were extracted from a nationwide, prospective stroke unit registry. Study endpoints included symptomatic intracerebral hemorrhage (sICH), early neurologic deterioration ≥4 NIHSS points (END), and 3-month functional outcome by modified Rankin scale (mRS). RESULTS: A total of 1,195 mild stroke patients treated with IVT and 2,625 patients treated with DAPT were included. IVT patients were younger (68.1 vs 70.8 years), had less hypertension (72.8% vs 83.5%), diabetes (19% vs 28.8%), and a history of myocardial infarction (7.6% vs 9.2%), and slightly higher admission NIHSS scores (median 2 vs median 1) when compared with DAPT patients. After propensity score matching and multivariable adjustment, IVT was associated with sICH (4 [1.2%] vs 0) and END (adjusted odds ratio [aOR] 2.8, 95% CI 1.1-7.5), and there was no difference in mRS 0-1 at 3 months (aOR 1.3, 95% CI 0.7-2.6). DISCUSSION: This analysis from a prospective nationwide stroke unit network indicates that IVT is not superior to DAPT in the setting of mild noncardioembolic stroke and may eventually be associated with harm. Further research focusing on acute therapy of mild stroke is highly warranted. CLASSIFICATION OF EVIDENCE: This study provides Class III evidence that IVT is not superior to DAPT in patients with acute mild (NIHSS score ≤3) noncardioembolic stroke. The study lacks the statistical precision to exclude clinically important superiority of either therapy.


Sujet(s)
Encéphalopathie ischémique , Accident vasculaire cérébral ischémique , Accident vasculaire cérébral , Humains , Fibrinolytiques/usage thérapeutique , Antiagrégants plaquettaires/usage thérapeutique , Accident vasculaire cérébral ischémique/traitement médicamenteux , Traitement thrombolytique/effets indésirables , Résultat thérapeutique , Accident vasculaire cérébral/thérapie , Hémorragie cérébrale/étiologie , Encéphalopathie ischémique/complications , Encéphalopathie ischémique/traitement médicamenteux
17.
Int J Parasitol ; 53(13): 751-761, 2023 Nov.
Article de Anglais | MEDLINE | ID: mdl-37516335

RÉSUMÉ

Ticks are important vectors of human and animal pathogens, but many questions remain unanswered regarding their taxonomy. Molecular sequencing methods have allowed research to start understanding the evolutionary history of even closely related tick species. Ixodes inopinatus is considered a sister species and highly similar to Ixodes ricinus, an important vector of many tick-borne pathogens in Europe, but identification between these species remains ambiguous with disagreement on the geographic extent of I. inopinatus. In 2018-2019, 1583 ticks were collected from breeding great tits (Parus major) in southern Germany, of which 45 were later morphologically identified as I. inopinatus. We aimed to confirm morphological identification using molecular tools. Utilizing two genetic markers (16S rRNA, TROSPA) and whole genome sequencing of specific ticks (n = 8), we were able to determine that German samples, morphologically identified as I. inopinatus, genetically represent I. ricinus regardless of previous morphological identification, and most likely are not I. ricinus/I. inopinatus hybrids. Further, our results showed that the entire mitochondrial genome, let alone singular mitochondrial genes (i.e., 16S), is unable to distinguish between I. ricinus and I. inopinatus. Our results suggest that I. inopinatus is geographically isolated as a species (northern Africa and potentially southern Spain and Portugal) and brings into question whether I. inopinatus exists in central Europe. Our results highlight the probable existence of I. inopinatus and the power of utilizing genomic data in answering questions regarding tick taxonomy.


Sujet(s)
Ixodes , Humains , Animaux , Ixodes/génétique , ARN ribosomique 16S/génétique , Europe , Allemagne , Portugal
18.
R Soc Open Sci ; 10(6): 230423, 2023 Jun.
Article de Anglais | MEDLINE | ID: mdl-37351491

RÉSUMÉ

Well-annotated and contiguous genomes are an indispensable resource for understanding the evolution, development, and metabolic capacities of organisms. Sponges, an ecologically important non-bilaterian group of primarily filter-feeding sessile aquatic organisms, are underrepresented with respect to available genomic resources. Here we provide a high-quality and well-annotated genome of Aphrocallistes vastus, a glass sponge (Porifera: Hexactinellida) that forms large reef structures off the coast of British Columbia (Canada). We show that its genome is approximately 80 Mb, small compared to most other metazoans, and contains nearly 2500 nested genes, more than other genomes. Hexactinellida is characterized by a unique skeletal architecture made of amorphous silicon dioxide (SiO2), and we identified 419 differentially expressed genes between the osculum, i.e. the vertical growth zone of the sponge, and the main body. Among the upregulated ones, mineralization-related genes such as glassin, as well as collagens and actins, dominate the expression profile during growth. Silicateins, suggested being involved in silica mineralization, especially in demosponges, were not found at all in the A. vastus genome and suggests that the underlying mechanisms of SiO2 deposition in the Silicea sensu stricto (Hexactinellida + Demospongiae) may not be homologous.

19.
Hypertension ; 80(7): 1555-1567, 2023 07.
Article de Anglais | MEDLINE | ID: mdl-37125608

RÉSUMÉ

BACKGROUND: Primary aldosteronism is frequently caused by an adrenocortical aldosterone-producing adenoma (APA) carrying a somatic mutation that drives aldosterone overproduction. APAs with a mutation in KCNJ5 (APA-KCNJ5MUT) are characterized by heterogeneous CYP11B2 (aldosterone synthase) expression, a particular cellular composition and larger tumor diameter than those with wild-type KCNJ5 (APA-KCNJ5WT). We exploited these differences to decipher the roles of transcriptome and metabolome reprogramming in tumor pathogenesis. METHODS: Consecutive adrenal cryosections (7 APAs and 7 paired adjacent adrenal cortex) were analyzed by spatial transcriptomics (10x Genomics platform) and metabolomics (in situ matrix-assisted laser desorption/ionization mass spectrometry imaging) co-integrated with CYP11B2 immunohistochemistry. RESULTS: We identified intratumoral transcriptional heterogeneity that delineated functionally distinct biological pathways. Common transcriptomic signatures were established across all APA specimens which encompassed 2 distinct transcriptional profiles in CYP11B2-immunopositive regions (CYP11B2-type 1 or 2). The CYP11B2-type 1 signature was characterized by zona glomerulosa gene markers and was detected in both APA-KCNJ5MUT and APA-KCNJ5WT. The CYP11B2-type 2 signature displayed markers of the zona fasciculata or reticularis and predominated in APA-KCNJ5MUT. Metabolites that promote oxidative stress and cell death accumulated in APA-KCNJ5WT. In contrast, antioxidant metabolites were abundant in APA-KCNJ5MUT. Finally, APA-like cell subpopulations-negative for CYP11B2 gene expression-were identified in adrenocortical tissue adjacent to APAs suggesting the existence of tumor precursor states. CONCLUSIONS: Our findings provide insight into intra- and intertumoral transcriptional heterogeneity and support a role for prooxidant versus antioxidant systems in APA pathogenesis highlighting genotype-dependent capacities for tumor expansion.


Sujet(s)
Adénomes , Tumeurs corticosurrénaliennes , Adénome corticosurrénalien , Hyperaldostéronisme , Humains , Aldostérone/métabolisme , Cytochrome P-450 CYP11B2/génétique , Cytochrome P-450 CYP11B2/métabolisme , Antioxydants , Multi-omique , Hyperaldostéronisme/métabolisme , Adénome corticosurrénalien/métabolisme , Génotype , Mutation , Adénomes/métabolisme , Canaux potassiques rectifiants entrants couplés aux protéines G/génétique , Canaux potassiques rectifiants entrants couplés aux protéines G/métabolisme , Tumeurs corticosurrénaliennes/génétique , Tumeurs corticosurrénaliennes/complications
20.
Life Sci Alliance ; 6(6)2023 06.
Article de Anglais | MEDLINE | ID: mdl-36977594

RÉSUMÉ

The IFN system constitutes a powerful antiviral defense machinery. Consequently, effective IFN responses protect against severe COVID-19 and exogenous IFNs inhibit SARS-CoV-2 in vitro. However, emerging SARS-CoV-2 variants of concern (VOCs) may have evolved reduced IFN sensitivity. Here, we determined differences in replication and IFN susceptibility of an early SARS-CoV-2 isolate (NL-02-2020) and the Alpha, Beta, Gamma, Delta, and Omicron VOCs in Calu-3 cells, iPSC-derived alveolar type-II cells (iAT2) and air-liquid interface (ALI) cultures of primary human airway epithelial cells. Our data show that Alpha, Beta, and Gamma replicated to similar levels as NL-02-2020. In comparison, Delta consistently yielded higher viral RNA levels, whereas Omicron was attenuated. All viruses were inhibited by type-I, -II, and -III IFNs, albeit to varying extend. Overall, Alpha was slightly less sensitive to IFNs than NL-02-2020, whereas Beta, Gamma, and Delta remained fully sensitive. Strikingly, Omicron BA.1 was least restricted by exogenous IFNs in all cell models. Our results suggest that enhanced innate immune evasion rather than higher replication capacity contributed to the effective spread of Omicron BA.1.


Sujet(s)
COVID-19 , Interférons , Humains , Interférons/pharmacologie , SARS-CoV-2 , Antiviraux/pharmacologie
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