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1.
Virology ; 600: 110218, 2024 Sep 03.
Artículo en Inglés | MEDLINE | ID: mdl-39276670

RESUMEN

Emerging viruses, such as novel influenza A viruses (IAV) and severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), pose a constant threat to animal and human health. Identification of host cell factors necessary for viral replication but dispensable for cellular survival might reveal novel, attractive targets for therapeutic intervention. Proteolytic activation of IAV hemagglutinin (HA) and SARS-CoV-2 spike protein (S) by the type II transmembrane serine protease (TTSPs), e.g. TMPRSS2 is sought to be critical for viral spread and pathogenesis. Here, we investigated the secondary structure of TMPRSS2 mRNA coding sequence and designed TMPRSS2-specific antisense oligonucleotides (ASOs). Several of these ASOs markedly reduced the TMPRSS2 expression and decreased IAV infection and SARS-CoV-2 entry into cells.

2.
Eur J Cancer ; 211: 114329, 2024 Sep 12.
Artículo en Inglés | MEDLINE | ID: mdl-39293346

RESUMEN

PURPOSE: The assessment of p16INK4a (p16) in oropharyngeal squamous cell carcinoma (OPSCC) has been incorporated into tumor classification, as p16 has been shown to impact survival probability. However, a recent study demonstrated that human papillomavirus (HPV) status in addition to p16 may have a better discriminatory effect on survival probability. This study aims to determine the impact of combined evaluation of p16 and HPV on prognosis. METHODS: This was a multicenter, multinational analysis including retrospective and prospective cohorts of patients treated for primary OPSCC with curative intent, based on the data of the HNCIG-EPIC study. The primary outcome was to determine how the combined assessment of HPV and p16 status predicts prognosis of patients with OPSCC compared to p16 assessment alone. We employed multivariable analyses models to compute hazard ratios regarding survival. Analyses were stratified by stage, smoking status, and sub-anatomical region. RESULTS: The study included 7654 patients, with approximately half of the tumors being p16-negative (50.3 %, n = 3849). A total of 9.2 % of patients had discordant p16 and HPV status (n = 704). HPV status significantly impacted overall survival and disease-free survival regardless of p16 status and across both UICC 8th stage I-II and III-IVb cancers. p16-positive/HPV-positive OPSCC patients exhibited the best survival probability. CONCLUSION: The detection of HPV had a significant impact on survival probability for OPSCC patients with both p16-positive and p16-negative tumors. HPV testing should be integrated in cancer staging, especially in regions of low attributable fraction, alongside p16 evaluation to ensure a comprehensive assessment of prognosis.

3.
J Chem Eng Data ; 69(8): 2688-2699, 2024 Aug 08.
Artículo en Inglés | MEDLINE | ID: mdl-39139987

RESUMEN

Density, viscosity, and self-diffusion coefficients are reported for octan-1-ol and the related ether-alcohols 2-pentoxy-ethan-1-ol, 3-butoxypropan-1-ol, 4-propoxybutan-1-ol, 5-ethoxypentan-1-ol, and 6-methoxyhexan-1-ol covering temperature ranges from 298.15 to 359.15 K. These new data reveal structure-property relationships affected by the presence and the position of the ether moiety in the molecular structure of the ether-alcohols. Compared to octan-1-ol, the presence of the ether moiety causes an increase in intermolecular hydrogen bonding interactions, resulting in higher densities. The increase in density is less pronounced for those ether-octanols that engage in intramolecular hydrogen bonding. As for the effects of the ether moiety on the dynamics, these are generally faster for the ether-alcohols compared to octan-1-ol, suggesting that hydrogen bonding between ether oxygen and hydroxy hydrogen is weaker compared to hydrogen bonding between two hydroxy groups. The activation energies obtained from an Arrhenius analysis are higher for translational motion than for momentum transfer for all alcohols. There are additional finer details across the ether alcohols for these activation barriers. These differences cancel out for the mathematical product of self-diffusion coefficient and viscosity (Dη). The effect of water impurities on the studied properties was also investigated and found to lead to small increases in densities for all alcohols. Viscosities decrease for octan-1-ol and 2-pentoxyethan-1-ol but increase for the other ether-alcohols that can engage in intramolecular hydrogen bonding.

4.
mBio ; 15(9): e0107724, 2024 Sep 11.
Artículo en Inglés | MEDLINE | ID: mdl-39115315

RESUMEN

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) spike is the fusion machine for host cell entry. Still, the mechanism by which spike protein interacts with the target lipid membrane to facilitate membrane fusion during entry is not fully understood. Here, using steady-state membrane fusion and single-molecule fluorescence resonance energy transfer imaging of spike trimers on the surface of SARS-CoV-2 pseudovirion, we directly show that spike protein interacts with phosphatidylserine (PS) lipid in the target membrane for mediating fusion. We observed that the fusion peptide of the spike S2 domain interacts with the PS lipid of the target membrane. Low pH and Ca2+ trigger the spike conformational change and bring fusion peptide in close proximity to the PS lipid of the membrane. The binding of the spike with PS lipid of its viral membrane (cis interaction) impedes the fusion activation. PS on the target membrane promotes spike binding via trans interaction, prevents the cis interaction, and accelerates fusion. Sequestering or absence of PS lipid abrogates the spike-mediated fusion process and restricts SARS-CoV-2 infectivity. We found that PS-dependent interaction for fusion is conserved across all the SARS-CoV-2 spike variants of concern (D614G, Alpha, Beta, Delta, and Omicron). Our study suggests that PS lipid is indispensable for SARS-CoV-2 spike-mediated virus and target membrane fusion for entry, and restricting PS interaction with spike inhibits the SARS-CoV-2 spike-mediated entry. Therefore, PS is an important cofactor and acts as a molecular beacon in the target membrane for SARS-CoV-2 entry. IMPORTANCE: The role of lipids in the host cell target membrane for severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) entry is not clear. We do not know whether SARS-CoV-2 spike protein has any specificity in terms of lipid for membrane fusion reaction. Here, using in vitro reconstitution of membrane fusion assay and single-molecule fluorescence resonance energy transfer imaging of SARS-CoV-2 spike trimers on the surface of the virion, we have demonstrated that phosphatidylserine (PS) lipid plays a key role in SARS-CoV-2 spike-mediated membrane fusion reaction for entry. Membrane-externalized PS lipid strongly promotes spike-mediated membrane fusion and COVID-19 infection. Blocking externalized PS lipid with PS-binding protein or in the absence of PS, SARS-CoV-2 spike-mediated fusion is strongly inhibited. Therefore, PS is an important target for restricting viral entry and intervening spike, and PS interaction presents new targets for COVID-19 interventions.


Asunto(s)
Fusión de Membrana , Fosfatidilserinas , SARS-CoV-2 , Glicoproteína de la Espiga del Coronavirus , Internalización del Virus , Glicoproteína de la Espiga del Coronavirus/metabolismo , Glicoproteína de la Espiga del Coronavirus/química , Glicoproteína de la Espiga del Coronavirus/genética , Fosfatidilserinas/metabolismo , SARS-CoV-2/metabolismo , SARS-CoV-2/fisiología , Humanos , COVID-19/virología , COVID-19/metabolismo , Unión Proteica , Transferencia Resonante de Energía de Fluorescencia
5.
Nucleic Acids Res ; 52(17): 10144-10160, 2024 Sep 23.
Artículo en Inglés | MEDLINE | ID: mdl-39175109

RESUMEN

Most heritable diseases are polygenic. To comprehend the underlying genetic architecture, it is crucial to discover the clinically relevant epistatic interactions (EIs) between genomic single nucleotide polymorphisms (SNPs) (1-3). Existing statistical computational methods for EI detection are mostly limited to pairs of SNPs due to the combinatorial explosion of higher-order EIs. With NeEDL (network-based epistasis detection via local search), we leverage network medicine to inform the selection of EIs that are an order of magnitude more statistically significant compared to existing tools and consist, on average, of five SNPs. We further show that this computationally demanding task can be substantially accelerated once quantum computing hardware becomes available. We apply NeEDL to eight different diseases and discover genes (affected by EIs of SNPs) that are partly known to affect the disease, additionally, these results are reproducible across independent cohorts. EIs for these eight diseases can be interactively explored in the Epistasis Disease Atlas (https://epistasis-disease-atlas.com). In summary, NeEDL demonstrates the potential of seamlessly integrated quantum computing techniques to accelerate biomedical research. Our network medicine approach detects higher-order EIs with unprecedented statistical and biological evidence, yielding unique insights into polygenic diseases and providing a basis for the development of improved risk scores and combination therapies.


Asunto(s)
Epistasis Genética , Polimorfismo de Nucleótido Simple , Humanos , Teoría Cuántica , Herencia Multifactorial/genética , Enfermedad/genética , Biología Computacional/métodos , Algoritmos , Predisposición Genética a la Enfermedad
6.
Front Immunol ; 15: 1383086, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-39119342

RESUMEN

Current vaccines against COVID-19 elicit immune responses that are overall strong but wane rapidly. As a consequence, the necessary booster shots have contributed to vaccine fatigue. Hence, vaccines that would provide lasting protection against COVID-19 are needed, but are still unavailable. Cytomegaloviruses (CMVs) elicit lasting and uniquely strong immune responses. Used as vaccine vectors, they may be attractive tools that obviate the need for boosters. Therefore, we tested the murine CMV (MCMV) as a vaccine vector against COVID-19 in relevant preclinical models of immunization and challenge. We have previously developed a recombinant MCMV vaccine vector expressing the spike protein of the ancestral SARS-CoV-2 (MCMVS). In this study, we show that the MCMVS elicits a robust and lasting protection in young and aged mice. Notably, spike-specific humoral and cellular immunity was not only maintained but also even increased over a period of at least 6 months. During that time, antibody avidity continuously increased and expanded in breadth, resulting in neutralization of genetically distant variants, like Omicron BA.1. A single dose of MCMVS conferred rapid virus clearance upon challenge. Moreover, MCMVS vaccination controlled two variants of concern (VOCs), the Beta (B.1.135) and the Omicron (BA.1) variants. Thus, CMV vectors provide unique advantages over other vaccine technologies, eliciting broadly reactive and long-lasting immune responses against COVID-19.


Asunto(s)
Anticuerpos Antivirales , Vacunas contra la COVID-19 , COVID-19 , SARS-CoV-2 , Glicoproteína de la Espiga del Coronavirus , Animales , SARS-CoV-2/inmunología , SARS-CoV-2/genética , Ratones , Vacunas contra la COVID-19/inmunología , COVID-19/prevención & control , COVID-19/inmunología , Glicoproteína de la Espiga del Coronavirus/inmunología , Glicoproteína de la Espiga del Coronavirus/genética , Anticuerpos Antivirales/inmunología , Anticuerpos Antivirales/sangre , Muromegalovirus/inmunología , Muromegalovirus/genética , Femenino , Anticuerpos Neutralizantes/inmunología , Anticuerpos Neutralizantes/sangre , Ratones Endogámicos BALB C , Humanos , Vectores Genéticos , Inmunidad Celular , Inmunidad Humoral , Modelos Animales de Enfermedad
7.
Laryngorhinootologie ; 2024 Jul 12.
Artículo en Alemán | MEDLINE | ID: mdl-38996431

RESUMEN

INTRODUCTION: Subglottic stenoses (SGS) are constrictions in the region below the vocal folds, that can pose a life-threatening problem for those affected. The aim of this research project was to identify the patient group for which the treatment of SGS by balloon dilatation can lead to long-term success. METHODS: 14 patients with SGS were examined (before and up to12 months after intervention) using pulmonary function tests, laryngoscopies and two questionnaires (Clinical Chronic Obstructive Pulmonary Disease Questionnaire), (modified Medical Research Council Dyspnoea Scale) regarding the respiratory situation. Additionally, the number of necessary interventions, the degree of stenosis (according to Myer Cotton and measured in millimeters) were documented. RESULTS: Four patients who required only one intervention with the balloon showed better pre-interventional respiratory function and a higher subjective stress level. Lung function tests and evaluation of the questionnaires showed an improvement in the respiratory situation and state of health of all 14 patients after the initial intervention. The degree of stenosis measured in millimeters shows that patients with a stenosis diameter of less than 4 mm only required one intervention. All patients who received an intervention using a 12-mm-balloon had to be treated several times. CONCLUSIONS: Patients with a high degree of stenosis and a tendency towards greater subjective stress and less objective restriction of the respiratory function appear to have a higher probability of long-term successful treatment with the balloon. Furthermore, the choice of balloon size seems to be an additional decisive factor for the success of an intervention.

8.
Mucosal Immunol ; 2024 Jun 18.
Artículo en Inglés | MEDLINE | ID: mdl-38901763

RESUMEN

T lymphocytes and myeloid cells express the immunoglobulin-like glycoprotein cluster of differentiation (CD)101, notably in the gut. Here, we investigated the cell-specific functions of CD101 during dextran sulfate sodium (DSS)-induced colitis and Salmonella enterica Typhimurium infection. Similar to conventional CD101-/- mice, animals with a regulatory T cell-specific Cd101 deletion developed more severe intestinal pathology than littermate controls in both models. While the accumulation of T helper 1 cytokines in a CD101-deficient environment entertained DSS-induced colitis, it impeded the replication of Salmonella as revealed by studying CD101-/- x interferon-g-/- mice. Moreover, CD101-expressing neutrophils were capable to restrain Salmonella infection in vitro and in vivo. Both cell-intrinsic and -extrinsic mechanisms of CD101 contributed to the control of bacterial growth and spreading. The CD101-dependent containment of Salmonella infection required the expression of Irg-1 and Nox2 and the production of itaconate and reactive oxygen species. The level of intestinal microbial antigens in the sera of inflammatory bowel disease patients correlated inversely with the expression of CD101 on myeloid cells, which is in line with the suppression of CD101 seen in mice following DSS application or Salmonella infection. Thus, depending on the experimental or clinical setting, CD101 helps to limit inflammatory insults or bacterial infections due to cell type-specific modulation of metabolic, immune-regulatory, and anti-microbial pathways.

9.
Nucleic Acids Res ; 52(W1): W481-W488, 2024 Jul 05.
Artículo en Inglés | MEDLINE | ID: mdl-38783119

RESUMEN

In recent decades, the development of new drugs has become increasingly expensive and inefficient, and the molecular mechanisms of most pharmaceuticals remain poorly understood. In response, computational systems and network medicine tools have emerged to identify potential drug repurposing candidates. However, these tools often require complex installation and lack intuitive visual network mining capabilities. To tackle these challenges, we introduce Drugst.One, a platform that assists specialized computational medicine tools in becoming user-friendly, web-based utilities for drug repurposing. With just three lines of code, Drugst.One turns any systems biology software into an interactive web tool for modeling and analyzing complex protein-drug-disease networks. Demonstrating its broad adaptability, Drugst.One has been successfully integrated with 21 computational systems medicine tools. Available at https://drugst.one, Drugst.One has significant potential for streamlining the drug discovery process, allowing researchers to focus on essential aspects of pharmaceutical treatment research.


Asunto(s)
Reposicionamiento de Medicamentos , Programas Informáticos , Reposicionamiento de Medicamentos/métodos , Humanos , Internet , Descubrimiento de Drogas/métodos , Biología de Sistemas/métodos , Biología Computacional/métodos
10.
Vaccines (Basel) ; 12(5)2024 May 01.
Artículo en Inglés | MEDLINE | ID: mdl-38793739

RESUMEN

Transmissibility and immune evasion of the recently emerged, highly mutated SARS-CoV-2 BA.2.87.1 are unknown. Here, we report that BA.2.87.1 efficiently enters human cells but is more sensitive to antibody-mediated neutralization than the currently dominating JN.1 variant. Acquisition of adaptive mutations might thus be needed for efficient spread in the population.

11.
Molecules ; 29(9)2024 Apr 30.
Artículo en Inglés | MEDLINE | ID: mdl-38731561

RESUMEN

Polyethylene glycol (PEG) is one of the environmentally benign solvent options for green chemistry. It readily absorbs water when exposed to the atmosphere. The Molecular Dynamics (MD) simulations of PEG200, a commercial mixture of low molecular weight polyethyelene glycol oligomers, as well as di-, tetra-, and hexaethylene glycol are presented to study the effect of added water impurities up to a weight fraction of 0.020, which covers the typical range of water impurities due to water absorption from the atmosphere. Each system was simulated a total of four times using different combinations of two force fields for the water (SPC/E and TIP4P/2005) and two force fields for the PEG and oligomer (OPLS-AA and modified OPLS-AA). The observed trends in the effects of water addition were qualitatively quite robust with respect to these force field combinations and showed that the water does not aggregate but forms hydrogen bonds at most between two water molecules. In general, the added water causes overall either no or very small and nuanced effects in the simulation results. Specifically, the obtained water RDFs are mostly identical regardless of the water content. The added water reduces oligomer hydrogen bonding interactions overall as it competes and forms hydrogen bonds with the oligomers. The loss of intramolecular oligomer hydrogen bonding is in part compensated by oligomers switching from inter- to intramolecular hydrogen bonding. The interplay of the competing hydrogen bonding interactions leads to the presence of shallow extrema with respect to the water weight fraction dependencies for densities, viscosities, and self-diffusion coefficients, in contrast to experimental measurements, which show monotonous dependencies. However, these trends are very small in magnitude and thus confirm the experimentally observed insensitivity of these physical properties to the presence of water impurities.

12.
iScience ; 27(6): 109904, 2024 Jun 21.
Artículo en Inglés | MEDLINE | ID: mdl-38812550

RESUMEN

In July/August 2023, the highly mutated severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) BA.2.86 lineage emerged and its descendant JN.1 is on track to become the dominant SARS-CoV-2 lineage globally. Compared to the spike (S) protein of the parental BA.2.86 lineage, the JN.1 S protein contains one mutation, L455S, which may affect receptor binding and antibody evasion. Here, we performed a virological assessment of the JN.1 lineage employing pseudovirus particles bearing diverse SARS-CoV-2 S proteins. Using this strategy, it was found that S protein mutation L455S confers increased neutralization resistance but reduces ACE2 binding capacity and S protein-driven cell entry efficiency. Altogether, these data suggest that the benefit of increased antibody evasion outweighs the reduced ACE2 binding capacity and further enabled the JN.1 lineage to effectively spread in the human population.

13.
Ann Rheum Dis ; 2024 May 03.
Artículo en Inglés | MEDLINE | ID: mdl-38702177

RESUMEN

Due to optimised treatment strategies and the availability of new therapies during the last decades, formerly devastating chronic inflammatory diseases such as rheumatoid arthritis or systemic sclerosis (SSc) have become less menacing. However, in many patients, even state-of-the-art treatment cannot induce remission. Moreover, the risk for flares strongly increases once anti-inflammatory therapy is tapered or withdrawn, suggesting that underlying pathological processes remain active even in the absence of overt inflammation. It has become evident that tissues have the ability to remember past encounters with pathogens, wounds and other irritants, and to react more strongly and/or persistently to the next occurrence. This priming of the tissue bears a paramount role in defence from microbes, but on the other hand drives inflammatory pathologies (the Dr Jekyll and Mr Hyde aspect of tissue adaptation). Emerging evidence suggests that long-lived tissue-resident cells, such as fibroblasts, macrophages, long-lived plasma cells and tissue-resident memory T cells, determine inflammatory tissue priming in an interplay with infiltrating immune cells of lymphoid and myeloid origin, and with systemically acting factors such as cytokines, extracellular vesicles and antibodies. Here, we review the current state of science on inflammatory tissue priming, focusing on tissue-resident and tissue-occupying cells in arthritis and SSc, and reflect on the most promising treatment options targeting the maladapted tissue response during these diseases.

14.
Eur J Immunol ; 54(7): e2451056, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-38593351

RESUMEN

COVID-19 induces re-circulating long-lived memory B cells (MBC) that, upon re-encounter with the pathogen, are induced to mount immunoglobulin responses. During convalescence, antibodies are subjected to affinity maturation, which enhances the antibody binding strength and generates new specificities that neutralize virus variants. Here, we performed a single-cell RNA sequencing analysis of spike-specific B cells from a SARS-CoV-2 convalescent subject. After COVID-19 vaccination, matured infection-induced MBC underwent recall and differentiated into plasmablasts. Furthermore, the transcriptomic profiles of newly activated B cells transiently shifted toward the ones of atypical and CXCR3+ B cells and several B-cell clonotypes massively expanded. We expressed monoclonal antibodies (mAbs) from all B-cell clones from the largest clonotype that used the VH3-53 gene segment. The in vitro analysis revealed that some somatic hypermutations enhanced the neutralization breadth of mAbs in a putatively stochastic manner. Thus, somatic hypermutation of B-cell clonotypes generates an anticipatory memory that can neutralize new virus variants.


Asunto(s)
Anticuerpos Neutralizantes , Anticuerpos Antivirales , COVID-19 , SARS-CoV-2 , Hipermutación Somática de Inmunoglobulina , SARS-CoV-2/inmunología , Humanos , Hipermutación Somática de Inmunoglobulina/genética , COVID-19/inmunología , Anticuerpos Neutralizantes/inmunología , Anticuerpos Antivirales/inmunología , Células B de Memoria/inmunología , Glicoproteína de la Espiga del Coronavirus/inmunología , Glicoproteína de la Espiga del Coronavirus/genética , Anticuerpos Monoclonales/inmunología , Linfocitos B/inmunología , Región Variable de Inmunoglobulina/genética , Región Variable de Inmunoglobulina/inmunología , Memoria Inmunológica/inmunología , Vacunas contra la COVID-19/inmunología
15.
Viruses ; 16(4)2024 04 10.
Artículo en Inglés | MEDLINE | ID: mdl-38675925

RESUMEN

The interferon-induced host cell protein Shiftless (SFL) inhibits -1 programmed ribosomal frameshifting (-1PRF) required for the expression of HIV-1 Gal-Pol and the formation of infectious HIV-1 particles. However, the specific regions in SFL required for antiviral activity and the mechanism by which SFL inhibits -1PRF remain unclear. Employing alanine scanning mutagenesis, we found that basic amino acids in the predicted zinc ribbon motif of SFL are essential for the suppression of Gag-Pol expression but dispensable for anti-HIV-1 activity. We have shown that SFL inhibits the expression of the murine leukemia virus (MLV) Gag-Pol polyprotein and the formation of infectious MLV particles, although Gag-Pol expression of MLV is independent of -1PRF but requires readthrough of a stop codon. These findings indicate that SFL might inhibit HIV-1 infection by more than one mechanism and that SFL might target programmed translational readthrough as well as -1PRF signals, both of which are regulated by mRNA secondary structure elements.


Asunto(s)
Proteínas de Fusión gag-pol , Infecciones por VIH , VIH-1 , Proteínas de Unión al ARN , Humanos , Sistema de Lectura Ribosómico , Proteínas de Fusión gag-pol/genética , Proteínas de Fusión gag-pol/metabolismo , Regulación Viral de la Expresión Génica , Células HEK293 , Infecciones por VIH/virología , Infecciones por VIH/genética , Infecciones por VIH/metabolismo , VIH-1/genética , VIH-1/fisiología , Virus de la Leucemia Murina/genética , Virus de la Leucemia Murina/fisiología , Replicación Viral , Proteínas de Unión al ARN/metabolismo
16.
Molecules ; 29(7)2024 Apr 08.
Artículo en Inglés | MEDLINE | ID: mdl-38611950

RESUMEN

This review gives an overview of current trends in the investigation of confined molecules such as water, small and higher alcohols, carbonic acids, ethylene glycol, and non-ionic surfactants, such as polyethylene glycol or Triton-X, as guest molecules in neat and functionalized mesoporous silica materials employing solid-state NMR spectroscopy, supported by calorimetry and molecular dynamics simulations. The combination of steric interactions, hydrogen bonds, and hydrophobic and hydrophilic interactions results in a fascinating phase behavior in the confinement. Combining solid-state NMR and relaxometry, DNP hyperpolarization, molecular dynamics simulations, and general physicochemical techniques, it is possible to monitor these confined molecules and gain deep insights into this phase behavior and the underlying molecular arrangements. In many cases, the competition between hydrogen bonding and electrostatic interactions between polar and non-polar moieties of the guests and the host leads to the formation of ordered structures, despite the cramped surroundings inside the pores.

17.
Nat Microbiol ; 9(4): 905-921, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38528146

RESUMEN

Some viruses are rarely transmitted orally or sexually despite their presence in saliva, breast milk, or semen. We previously identified that extracellular vesicles (EVs) in semen and saliva inhibit Zika virus infection. However, the antiviral spectrum and underlying mechanism remained unclear. Here we applied lipidomics and flow cytometry to show that these EVs expose phosphatidylserine (PS). By blocking PS receptors, targeted by Zika virus in the process of apoptotic mimicry, they interfere with viral attachment and entry. Consequently, physiological concentrations of EVs applied in vitro efficiently inhibited infection by apoptotic mimicry dengue, West Nile, Chikungunya, Ebola and vesicular stomatitis viruses, but not severe acute respiratory syndrome coronavirus 2, human immunodeficiency virus 1, hepatitis C virus and herpesviruses that use other entry receptors. Our results identify the role of PS-rich EVs in body fluids in innate defence against infection via viral apoptotic mimicries, explaining why these viruses are primarily transmitted via PS-EV-deficient blood or blood-ingesting arthropods rather than direct human-to-human contact.


Asunto(s)
Líquidos Corporales , Vesículas Extracelulares , Virus , Infección por el Virus Zika , Virus Zika , Femenino , Humanos , Fosfatidilserinas , Acoplamiento Viral
18.
Biochimie ; 2024 Mar 01.
Artículo en Inglés | MEDLINE | ID: mdl-38432290

RESUMEN

SARS-CoV-2 mainly infects the respiratory tract but can also target other organs, including the central nervous system. While it was recently shown that cells of the blood-brain-barrier are permissive to SARS-CoV-2 infection in vitro, it remains debated whether neurons can be infected. In this study, we demonstrate that vesicular stomatitis virus particles pseudotyped with the spike protein of SARS-CoV-2 variants WT, Alpha, Delta and Omicron enter the neuronal model cell line SH-SY5Y. Cell biological analyses of the pseudo-virus treated cultures showed marked alterations in microtubules of SH-SY5Y cells. Because the changes in ß-tubulin occurred in most cells, but only few were infected, we further asked whether interaction of the cells with spike protein might be sufficient to cause molecular and structural changes. For this, SH-SY5Y cells were incubated with trimeric spike proteins for time intervals of up to 24 h. CellProfiler™-based image analyses revealed changes in the intensities of microtubule staining in spike protein-incubated cells. Furthermore, expression of the spike protein-processing protease cathepsin L was found to be up-regulated by wild type, Alpha and Delta spike protein pseudotypes and cathepsin L was found to be secreted from spike protein-treated cells. We conclude that the mere interaction of the SARS-CoV-2 with neuronal cells can affect cellular architecture and proteolytic capacities. The molecular mechanisms underlying SARS-CoV-2 spike protein induced cytoskeletal changes in neuronal cells remain elusive and require future studies.

19.
Sci Rep ; 14(1): 2808, 2024 02 02.
Artículo en Inglés | MEDLINE | ID: mdl-38307916

RESUMEN

Bulk RNA sequencing (RNA-seq) of blood is typically used for gene expression analysis in biomedical research but is still rarely used in clinical practice. In this study, we propose that RNA-seq should be considered a diagnostic tool, as it offers not only insights into aberrant gene expression and splicing but also delivers additional readouts on immune cell type composition as well as B-cell and T-cell receptor (BCR/TCR) repertoires. We demonstrate that RNA-seq offers insights into a patient's immune status via integrative analysis of RNA-seq data from patients infected with various SARS-CoV-2 variants (in total 196 samples with up to 200 million reads sequencing depth). We compare the results of computational cell-type deconvolution methods (e.g., MCP-counter, xCell, EPIC, quanTIseq) to complete blood count data, the current gold standard in clinical practice. We observe varying levels of lymphocyte depletion and significant differences in neutrophil levels between SARS-CoV-2 variants. Additionally, we identify B and T cell receptor (BCR/TCR) sequences using the tools MiXCR and TRUST4 to show that-combined with sequence alignments and BLASTp-they could be used to classify a patient's disease. Finally, we investigated the sequencing depth required for such analyses and concluded that 10 million reads per sample is sufficient. In conclusion, our study reveals that computational cell-type deconvolution and BCR/TCR methods using bulk RNA-seq analyses can supplement missing CBC data and offer insights into immune responses, disease severity, and pathogen-specific immunity, all achievable with a sequencing depth of 10 million reads per sample.


Asunto(s)
COVID-19 , SARS-CoV-2 , Humanos , SARS-CoV-2/genética , COVID-19/genética , Perfilación de la Expresión Génica , Receptores de Antígenos de Linfocitos T/genética , Análisis de Secuencia de ARN/métodos , Inmunidad
20.
bioRxiv ; 2024 Jan 15.
Artículo en Inglés | MEDLINE | ID: mdl-38313260

RESUMEN

RNA sequencing offers unique insights into transcriptome diversity, and a plethora of tools have been developed to analyze alternative splicing. One important task is to detect changes in the relative transcript abundance in differential transcript usage (DTU) analysis. The choice of the right analysis tool is non-trivial and depends on experimental factors such as the availability of single- or paired-end and bulk or single-cell data. To help users select the most promising tool for their task, we performed a comprehensive benchmark of DTU detection tools. We cover a wide array of experimental settings, using simulated bulk and single-cell RNA-seq data as well as real transcriptomics datasets, including time-series data. Our results suggest that DEXSeq, edgeR, and LimmaDS are better choices for paired-end data, while DSGseq and DEXSeq can be used for single-end data. In single-cell simulation settings, we showed that satuRn performs better than DTUrtle. In addition, we showed that Spycone is optimal for time series DTU/IS analysis based on the evidence provided using GO terms enrichment analysis.

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