Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 294
Filtrar
2.
Int J Mol Sci ; 24(23)2023 Nov 22.
Artigo em Inglês | MEDLINE | ID: mdl-38068938

RESUMO

The limited availability of antiviral therapy for severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has spurred the search for novel antiviral drugs. Here, we investigated the potential antiviral properties of plants adapted to high-salt environments collected in the north of France. Twenty-five crude methanolic extracts obtained from twenty-two plant species were evaluated for their cytotoxicity and antiviral effectiveness against coronaviruses HCoV-229E and SARS-CoV-2. Then, a bioguided fractionation approach was employed. The most active crude methanolic extracts were partitioned into three different sub-extracts. Notably, the dichloromethane sub-extract of the whole plant Hippophae rhamnoides L. demonstrated the highest antiviral activity against both viruses. Its chemical composition was evaluated by ultra-high performance liquid chromatography (UHPLC) coupled with mass spectrometry (MS) and then it was fractionated by centrifugal partition chromatography (CPC). Six cinnamoyl triterpenoid compounds were isolated from the three most active fractions by preparative high-performance liquid chromatography (HPLC) and identified by high resolution MS (HR-MS) and mono- and bi-dimensional nuclear magnetic resonance (NMR). Specifically, these compounds were identified as 2-O-trans-p-coumaroyl-maslinic acid, 3ß-hydroxy-2α-trans-p-coumaryloxy-urs-12-en-28-oic acid, 3ß-hydroxy-2α-cis-p-coumaryloxy-urs-12-en-28-oic acid, 3-O-trans-caffeoyl oleanolic acid, a mixture of 3-O-trans-caffeoyl oleanolic acid/3-O-cis-caffeoyl oleanolic acid (70/30), and 3-O-trans-p-coumaroyl oleanolic acid. Infection tests demonstrated a dose-dependent inhibition of these triterpenes against HCoV-229E and SARS-CoV-2. Notably, cinnamoyl oleanolic acids displayed activity against both SARS-CoV-2 and HCoV-229E. Our findings suggest that Hippophae rhamnoides could represent a source of potential antiviral agents against coronaviruses.


Assuntos
Coronavirus Humano 229E , Hippophae , Ácido Oleanólico , Triterpenos , Triterpenos/química , Hippophae/química , Plantas Tolerantes a Sal , Mar do Norte , SARS-CoV-2 , Antivirais/farmacologia , Antivirais/análise
4.
Cell Mol Life Sci ; 80(12): 353, 2023 Nov 09.
Artigo em Inglês | MEDLINE | ID: mdl-37940699

RESUMO

The coronavirus' (CoV) membrane (M) protein is the driving force during assembly, but this process remains poorly characterized. Previously, we described two motifs in the C-tail of the Middle East respiratory syndrome CoV (MERS-CoV) M protein involved in its endoplasmic reticulum (ER) exit (211DxE213) and trans-Golgi network (TGN) retention (199KxGxYR204). Here, their function in virus assembly was investigated by two different virus-like particle (VLP) assays and by mutating both motifs in an infectious MERS-CoV cDNA clone. It was shown that the 199KxGxYR204 motif was essential for VLP and infectious virus assembly. Moreover, the mislocalization of the M protein induced by mutation of this motif prevented M-E interaction. Hampering the ER export of M by mutating its 211DxE213 motif still allowed the formation of nucleocapsid-empty VLPs, but prevented the formation of fully assembled VLPs and infectious particles. Taken together, these data show that the MERS-CoV assembly process highly depends on the correct intracellular trafficking of its M protein, and hence that not only specific protein-protein interacting motifs but also correct subcellular localization of the M protein in infected cells is essential for virus formation and should be taken into consideration when studying the assembly process.


Assuntos
Proteínas de Membrana , Coronavírus da Síndrome Respiratória do Oriente Médio , Proteínas de Membrana/metabolismo , Coronavírus da Síndrome Respiratória do Oriente Médio/genética , Coronavírus da Síndrome Respiratória do Oriente Médio/metabolismo , Proteínas da Matriz Viral/genética , Proteínas da Matriz Viral/metabolismo , Proteínas do Nucleocapsídeo/genética , Proteínas do Nucleocapsídeo/metabolismo , Montagem de Vírus/genética
5.
Front Microbiol ; 14: 1254728, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37808318

RESUMO

Despite the introduction of effective treatments for hepatitis C in clinics, issues remain regarding the liver disease induced by chronic hepatitis C virus (HCV) infection. HCV is known to disturb the metabolism of infected cells, especially lipid metabolism and redox balance, but the mechanisms leading to HCV-induced pathogenesis are still poorly understood. In an APEX2-based proximity biotinylation screen, we identified ACBD5, a peroxisome membrane protein, as located in the vicinity of HCV replication complexes. Confocal microscopy confirmed the relocation of peroxisomes near HCV replication complexes and indicated that their morphology and number are altered in approximately 30% of infected Huh-7 cells. Peroxisomes are small versatile organelles involved among other functions in lipid metabolism and ROS regulation. To determine their importance in the HCV life cycle, we generated Huh-7 cells devoid of peroxisomes by inactivating the PEX5 and PEX3 genes using CRISPR/Cas9 and found that the absence of peroxisomes had no impact on replication kinetics or infectious titers of HCV strains JFH1 and DBN3a. The impact of HCV on peroxisomal functions was assessed using sub-genomic replicons. An increase of ROS was measured in peroxisomes of replicon-containing cells, correlated with a significant decrease of catalase activity with the DBN3a strain. In contrast, HCV replication had little to no impact on cytoplasmic and mitochondrial ROS, suggesting that the redox balance of peroxisomes is specifically impaired in cells replicating HCV. Our study provides evidence that peroxisome function and morphology are altered in HCV-infected cells.

6.
J Gen Virol ; 104(10)2023 10.
Artigo em Inglês | MEDLINE | ID: mdl-37800895

RESUMO

Coronaviruses are positive-stranded RNA enveloped viruses. The helical nucleocapsid is surrounded by a lipid bilayer in which are anchored three viral proteins: the spike (S), membrane (M) and envelope (E) proteins. The M protein is the major component of the viral envelope and is believed to be its building block. The M protein of Middle East respiratory syndrome coronavirus (MERS-CoV) and severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) contains a short N-terminal domain with an N-glycosylation site. We investigated their N-glycosylation and show that polylactosamine chains are conjugated to SARS-CoV-2 and MERS-CoV M proteins in transfected and infected cells. Acidic residues present in the first transmembrane segments of the proteins are required for their glycosylation. No specific signal to specify polylactosamine conjugation could be identified and high mannose-conjugated protein was incorporated into virus-like particles.


Assuntos
COVID-19 , Coronavírus da Síndrome Respiratória do Oriente Médio , Humanos , Coronavírus da Síndrome Respiratória do Oriente Médio/genética , SARS-CoV-2/metabolismo , Proteínas da Matriz Viral/genética , Proteínas de Membrana , Glicoproteína da Espícula de Coronavírus/genética , Glicoproteína da Espícula de Coronavírus/metabolismo
7.
Ann Bot ; 132(4): 787-800, 2023 11 25.
Artigo em Inglês | MEDLINE | ID: mdl-37777476

RESUMO

BACKGROUND AND AIMS: Epiphytism has evolved repeatedly in plants and has resulted in a considerable number of species with original characteristics. Because water supply is generally erratic compared to that in soils, succulent forms in particular are widespread in epiphytic species. However, succulent organs also exist in terrestrial plants, and the question of the concomitant evolution of epiphytism and succulence has received little attention, not even in the epidendroid orchids, which account for 67.6 % of vascular epiphytes. METHODS: We built a new time-calibrated phylogenetic tree of Epidendroideae with 203 genera treated in genus Orchidacearum, from which we reconstructed the evolution of epiphytism as well as traits related to water scarcity (stem and leaf succulence and the number of velamen layers), while testing for the correlated evolution between the two. Furthermore, we estimated the ancestral geographical ranges to evaluate the palaeoclimatic context in which epiphytism evolved. KEY RESULTS: Epiphytism evolved at least three times: 39.0 million years ago (Mya) in the common ancestor of the Malaxideae and Cymbidieae that probably ranged from the Neotropics to Southeast Asia and Australia, 11.5 Mya in the Arethuseae in Southeast Asia and Australia, and 7.1 Mya in the neotropical Sobralieae, and it was notably lost in the Malaxidiinae, Collabieae, Calypsoeae, Bletiinae and Eulophiinae. Stem succulence is inferred to have evolved once, in a terrestrial ancestor at least 4.1 Mya before the emergence of epiphytic lineages. If lost, stem succulence was almost systematically replaced by leaf succulence in epiphytic lineages. CONCLUSIONS: Epiphytism may have evolved in seasonally dry forests during the Eocene climatic cooling, among stem-succulent terrestrial orchids. Our results suggest that the emergence of stem succulence in early epidendroids was a key innovation in the evolution of epiphytism, facilitating the colonization of epiphytic environments that later led to the greatest diversification of epiphytic orchids.


Assuntos
Orchidaceae , Solo , Filogenia , Fenótipo , Florestas
8.
BMJ Open ; 13(9): e073691, 2023 09 07.
Artigo em Inglês | MEDLINE | ID: mdl-37678943

RESUMO

INTRODUCTION: Transvaginal natural orifice transluminal endoscopic surgery (vNOTES) has already proven its non-inferiority to conventional abdominal laparoscopy (CAL) for hysterectomy without conversion. The results in terms of efficacy and safety are promising. However, we note a lack of medical literature and no specific randomised controlled trial assessing women's sexual function after vNOTES for benign adnexal surgery. The aim of this RCT is to confirm the non-inferiority of the vNOTES approach for benign adnexal pathology compared with CAL on women's sexual function. Secondary outcomes will evaluate vNOTES's efficiency, morbidity and postoperative complications compared with CAL for benign adnexal surgery. The relationship between adnexal mass morcellation and the quality of the histological analysis will also be evaluated as secondary outcome. METHODS AND ANALYSIS: Women aged 18-70 years undergoing a benign adnexal surgery at the Geneva University Hospitals will be eligible and randomised with a 1:1 ratio to the CAL arm or the vNOTES arm, if inclusion criteria are met. Participants will complete the Female Sexual Function Index, the Couple Satisfaction Index-16 and a self-reported questionnaire on dyspareunia within 4 weeks prior to randomisation and at 3+6 months after surgery. General and clinical data will be collected when the patient is enrolled in the study, during hospitalisation and at 1 month postoperative to assess secondary outcomes.An absence of impairment on sexual function will be confirmed with a stability or an improvement of the evaluated scores in each group at 3 and 6 months postoperative compared with the preoperative scores. We expect to have no statistically significant difference in sexuality questionnaires scores between the two groups. ETHICS AND DISSEMINATION: Protocol of this study was validated by the Cantonal Research Ethics Commission of Geneva, Switzerland, on 9 August 2022. We aim to publish the study's results in peer-reviewed journals within 3 years. TRIAL REGISTRATION NUMBER: NCT05761275.


Assuntos
Dispareunia , Laparoscopia , Feminino , Humanos , Qualidade de Vida , Laparoscopia/efeitos adversos , Comportamento Sexual , Sexualidade , Dispareunia/etiologia , Ensaios Clínicos Controlados Aleatórios como Assunto
9.
Front Surg ; 10: 1101078, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36936661

RESUMO

Uterine leiomyoma is the most common benign tumour of the uterus in women of reproductive age. When removed surgically, a mini-invasive procedure is preferentially used (laparoscopic or robotic) and the extraction of the specimen can be managed by power morcellation. In this consecutive case-series, we present three cases of parasitic leiomyoma that appeared following previous surgical management of leiomyoma using the technique of laparoscopic myomectomy with uncontained power morcellation. The time frame in between the initial surgery and the diagnosis of the parasitic leiomyoma was 5.7 years. All three patients were diagnosed with endometriosis: 2 cases prior to the initial surgery and 1 case after the initial surgery. One hypothesis could be that, due to pelvic inflammation, endometriosis is a risk factor for iatrogenic parasitic leiomyoma development in case of uncontained morcellation of leiomyoma during myomectomy.

10.
Surg Endosc ; 37(7): 5215-5225, 2023 07.
Artigo em Inglês | MEDLINE | ID: mdl-36952046

RESUMO

BACKGROUND: Robotic surgery has gained popularity for the reconstruction of pelvic floor defects. Nonetheless, there is no evidence that robot-assisted reconstructive surgery is either appropriate or superior to standard laparoscopy for the performance of pelvic floor reconstructive procedures or that it is sustainable. The aim of this project was to address the proper role of robotic pelvic floor reconstructive procedures using expert opinion. METHODS: We set up an international, multidisciplinary group of 26 experts to participate in a Delphi process on robotics as applied to pelvic floor reconstructive surgery. The group comprised urogynecologists, urologists, and colorectal surgeons with long-term experience in the performance of pelvic floor reconstructive procedures and with the use of the robot, who were identified primarily based on peer-reviewed publications. Two rounds of the Delphi process were conducted. The first included 63 statements pertaining to surgeons' characteristics, general questions, indications, surgical technique, and future-oriented questions. A second round including 20 statements was used to reassess those statements where borderline agreement was obtained during the first round. The final step consisted of a face-to-face meeting with all participants to present and discuss the results of the analysis. RESULTS: The 26 experts agreed that robotics is a suitable indication for pelvic floor reconstructive surgery because of the significant technical advantages that it confers relative to standard laparoscopy. Experts considered these advantages particularly important for the execution of complex reconstructive procedures, although the benefits can be found also during less challenging cases. The experts considered the robot safe and effective for pelvic floor reconstruction and generally thought that the additional costs are offset by the increased surgical efficacy. CONCLUSION: Robotics is a suitable choice for pelvic reconstruction, but this Delphi initiative calls for more research to objectively assess the specific settings where robotic surgery would provide the most benefit.


Assuntos
Laparoscopia , Procedimentos Cirúrgicos Robóticos , Robótica , Cirurgia Plástica , Humanos , Diafragma da Pelve/cirurgia , Técnica Delphi , Procedimentos Cirúrgicos Robóticos/métodos , Laparoscopia/métodos
11.
Eur J Med Chem ; 250: 115186, 2023 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-36796300

RESUMO

Since end of 2019, the global and unprecedented outbreak caused by the coronavirus SARS-CoV-2 led to dramatic numbers of infections and deaths worldwide. SARS-CoV-2 produces two large viral polyproteins which are cleaved by two cysteine proteases encoded by the virus, the 3CL protease (3CLpro) and the papain-like protease, to generate non-structural proteins essential for the virus life cycle. Both proteases are recognized as promising drug targets for the development of anti-coronavirus chemotherapy. Aiming at identifying broad spectrum agents for the treatment of COVID-19 but also to fight emergent coronaviruses, we focused on 3CLpro that is well conserved within this viral family. Here we present a high-throughput screening of more than 89,000 small molecules that led to the identification of a new chemotype, potent inhibitor of the SARS-CoV-2 3CLpro. The mechanism of inhibition, the interaction with the protease using NMR and X-Ray, the specificity against host cysteine proteases and promising antiviral properties in cells are reported.


Assuntos
COVID-19 , SARS-CoV-2 , Humanos , SARS-CoV-2/metabolismo , Peptídeo Hidrolases , Cisteína Endopeptidases/metabolismo , Inibidores de Proteases/química , Proteases 3C de Coronavírus , Antivirais/química
12.
Mol Phylogenet Evol ; 182: 107687, 2023 05.
Artigo em Inglês | MEDLINE | ID: mdl-36581141

RESUMO

Dispersals have been shown to be critical to the evolution of the long isolated but megadiverse flora of Madagascar and the surrounding islands of the western Indian Ocean, but we are just beginning to understand the directionality of these dispersals. With more than half of its species occurring in the western Indian Ocean region (WIOR), the paleotropical subfamily Dombeyoideae provides a particularly useful case study through which to better understand the biogeography of the WIOR, and yet its biogeography is poorly understood. Here we sampled six molecular markers from all 20 genera in the Dombeyoideae to reconstruct the most complete phylogeny to date for the subfamily. From this, divergence times, calibrated with three fossils (two dombeyoid, one malvoid), and ancestral range estimations were hypothesized. Biogeographic stochastic mapping (BSM) analyses on the maximum clade credibility tree were completed and compared to BSM analyses on 1,000 trees randomly sampled from the posterior distribution of trees resulting from the dating analysis. We found the Dombeyoideae crown node diverged ca. 53 million years ago out of a broad ancestral range involving all three major areas of its distribution: Madagascar, Africa, and Asia. The majority of diversification and dispersals in the subfamily occurred within the last ca. 10 million years, mostly from the Pliocene onwards. There were roughly five dispersals from Madagascar to Africa (and only one in reverse), at least six from Madagascar to surrounding islands of the WIOR (Mascarenes and Comoros), and one dispersal from Madagascar to Asia (and ca. 1 in reverse). Other long-distance dispersals included one from Africa to St. Helena and one from Africa to Australasia, both from within the most widespread clade, the Cheirolaena & allies clade, and one dispersal from Asia to Africa. Critically, the Dombeyoideae provide strong evidence for considering the island of Madagascar as a source for the colonization of continents, as well as the surrounding islands of the WIOR. Furthermore, narrow sympatry was a key process in the evolution of the subfamily, particularly in Madagascar and the Mascarenes.


Assuntos
Malvaceae , Filogenia , Madagáscar , Filogeografia , África
13.
Cell Mol Life Sci ; 79(12): 615, 2022 Dec 03.
Artigo em Inglês | MEDLINE | ID: mdl-36460928

RESUMO

Although hepatitis E virus (HEV) is the major leading cause of enterically transmitted viral hepatitis worldwide, many gaps remain in the understanding of the HEV lifecycle. Notably, viral factories induced by HEV have not been documented yet, and it is currently unknown whether HEV infection leads to cellular membrane modeling as many positive-strand RNA viruses. HEV genome encodes the ORF1 replicase, the ORF2 capsid protein and the ORF3 protein involved in virion egress. Previously, we demonstrated that HEV produces different ORF2 isoforms including the virion-associated ORF2i form. Here, we generated monoclonal antibodies that specifically recognize the ORF2i form and antibodies that recognize the different ORF2 isoforms. One antibody, named P1H1 and targeting the ORF2i N-terminus, recognized delipidated HEV particles from cell culture and patient sera. Importantly, AlphaFold2 modeling demonstrated that the P1H1 epitope is exposed on HEV particles. Next, antibodies were used to probe viral factories in HEV-producing/infected cells. By confocal microscopy, we identified subcellular nugget-like structures enriched in ORF1, ORF2 and ORF3 proteins and viral RNA. Electron microscopy analyses revealed an unprecedented HEV-induced membrane network containing tubular and vesicular structures. We showed that these structures are dependent on ORF2i capsid protein assembly and ORF3 expression. An extensive colocalization study of viral proteins with subcellular markers, and silencing experiments demonstrated that these structures are derived from the endocytic recycling compartment (ERC) for which Rab11 is a central player. Hence, HEV hijacks the ERC and forms a membrane network of vesicular and tubular structures that might be the hallmark of HEV infection.


Assuntos
Vírus da Hepatite E , Humanos , Vírus da Hepatite E/genética , Compartimentos de Replicação Viral , Proteínas do Capsídeo , Transporte Biológico , Anticorpos Monoclonais
14.
Front Microbiol ; 13: 1031204, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36246297

RESUMO

The SARS-CoV-2 pandemic and the urgent need for massive antiviral testing highlighted the lack of a good cell-based assay that allowed for a fast, automated screening of antivirals in high-throughput content with minimal handling requirements in a BSL-3 environment. The present paper describes the construction of a green fluorescent substrate that, upon cleavage by the SARS-CoV-2 main protease, re-localizes from the cytoplasm in non-infected cells to the nucleus in infected cells. The construction was stably expressed, together with a red fluorescent nuclear marker, in a highly susceptible clone derived from Vero-81 cells. With this fluorescent reporter cell line, named F1G-red, SARS-CoV-2 infection can be scored automatically in living cells by comparing the patterns of green and red fluorescence signals acquired by automated confocal microscopy in a 384-well plate format. We show the F1G-red system is sensitive to several SARS-CoV-2 variants of concern and that it can be used to assess antiviral activities of compounds in dose-response experiments. This high-throughput system will provide a reliable tool for antiviral screening against SARS-CoV-2.

15.
PLoS Pathog ; 18(9): e1010799, 2022 09.
Artigo em Inglês | MEDLINE | ID: mdl-36067253

RESUMO

The binding of the SARS-CoV-2 spike to angiotensin-converting enzyme 2 (ACE2) promotes virus entry into the cell. Targeting this interaction represents a promising strategy to generate antivirals. By screening a phage-display library of biosynthetic protein sequences build on a rigid alpha-helicoidal HEAT-like scaffold (named αReps), we selected candidates recognizing the spike receptor binding domain (RBD). Two of them (F9 and C2) bind the RBD with affinities in the nM range, displaying neutralisation activity in vitro and recognizing distinct sites, F9 overlapping the ACE2 binding motif. The F9-C2 fusion protein and a trivalent αRep form (C2-foldon) display 0.1 nM affinities and EC50 of 8-18 nM for neutralization of SARS-CoV-2. In hamsters, F9-C2 instillation in the nasal cavity before or during infections effectively reduced the replication of a SARS-CoV-2 strain harbouring the D614G mutation in the nasal epithelium. Furthermore, F9-C2 and/or C2-foldon effectively neutralized SARS-CoV-2 variants (including delta and omicron variants) with EC50 values ranging from 13 to 32 nM. With their high stability and their high potency against SARS-CoV-2 variants, αReps provide a promising tool for SARS-CoV-2 therapeutics to target the nasal cavity and mitigate virus dissemination in the proximal environment.


Assuntos
Enzima de Conversão de Angiotensina 2 , Tratamento Farmacológico da COVID-19 , Proteínas Recombinantes de Fusão , Glicoproteína da Espícula de Coronavírus , Enzima de Conversão de Angiotensina 2/química , Enzima de Conversão de Angiotensina 2/metabolismo , Antivirais/química , Antivirais/farmacologia , Humanos , Peptidil Dipeptidase A/metabolismo , Ligação Proteica , Proteínas Recombinantes de Fusão/farmacologia , Proteínas Recombinantes de Fusão/uso terapêutico , Proteínas Recombinantes/farmacologia , Proteínas Recombinantes/uso terapêutico , SARS-CoV-2/genética , Glicoproteína da Espícula de Coronavírus/metabolismo
16.
PLoS Pathog ; 18(8): e1010798, 2022 08.
Artigo em Inglês | MEDLINE | ID: mdl-36007070

RESUMO

Hepatitis E virus (HEV) infection is the most common cause of acute viral hepatitis worldwide. Hepatitis E is usually asymptomatic and self-limiting but it can become chronic in immunocompromised patients and is associated with increased fulminant hepatic failure and mortality rates in pregnant women. HEV genome encodes three proteins including the ORF2 protein that is the viral capsid protein. Interestingly, HEV produces 3 isoforms of the ORF2 capsid protein which are partitioned in different subcellular compartments and perform distinct functions in the HEV lifecycle. Notably, the infectious ORF2 (ORF2i) protein is the structural component of virions, whereas the genome-free secreted and glycosylated ORF2 proteins likely act as a humoral immune decoy. Here, by using a series of ORF2 capsid protein mutants expressed in the infectious genotype 3 p6 HEV strain as well as chimeras between ORF2 and the CD4 glycoprotein, we demonstrated how an Arginine-Rich Motif (ARM) located in the ORF2 N-terminal region controls the fate and functions of ORF2 isoforms. We showed that the ARM controls ORF2 nuclear translocation likely to promote regulation of host antiviral responses. This motif also regulates the dual topology and functionality of ORF2 signal peptide, leading to the production of either cytosolic infectious ORF2i or reticular non-infectious glycosylated ORF2 forms. It serves as maturation site of glycosylated ORF2 by furin, and promotes ORF2-host cell membrane interactions. The identification of ORF2 ARM as a unique central regulator of the HEV lifecycle uncovers how viruses settle strategies to condense their genetic information and hijack cellular processes.


Assuntos
Vírus da Hepatite E , Hepatite E , Motivos de Aminoácidos , Proteínas do Capsídeo/química , Proteínas do Capsídeo/metabolismo , Feminino , Glicosilação , Hepatite E/genética , Hepatite E/metabolismo , Vírus da Hepatite E/crescimento & desenvolvimento , Humanos , Gravidez
17.
Nat Genet ; 54(8): 1090-1102, 2022 08.
Artigo em Inglês | MEDLINE | ID: mdl-35879413

RESUMO

CRISPR knockout (KO) screens have identified host factors regulating severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) replication. Here, we conducted a meta-analysis of these screens, which showed a high level of cell-type specificity of the identified hits, highlighting the necessity of additional models to uncover the full landscape of host factors. Thus, we performed genome-wide KO and activation screens in Calu-3 lung cells and KO screens in Caco-2 colorectal cells, followed by secondary screens in four human cell lines. This revealed host-dependency factors, including AP1G1 adaptin and ATP8B1 flippase, as well as inhibitors, including mucins. Interestingly, some of the identified genes also modulate Middle East respiratory syndrome coronavirus (MERS-CoV) and seasonal human coronavirus (HCoV) (HCoV-NL63 and HCoV-229E) replication. Moreover, most genes had an impact on viral entry, with AP1G1 likely regulating TMPRSS2 activity at the plasma membrane. These results demonstrate the value of multiple cell models and perturbational modalities for understanding SARS-CoV-2 replication and provide a list of potential targets for therapeutic interventions.


Assuntos
COVID-19 , Coronavírus da Síndrome Respiratória do Oriente Médio , COVID-19/genética , Células CACO-2 , Repetições Palindrômicas Curtas Agrupadas e Regularmente Espaçadas/genética , Humanos , Coronavírus da Síndrome Respiratória do Oriente Médio/genética , SARS-CoV-2/genética , Estações do Ano
18.
J Virol ; 96(13): e0047422, 2022 07 13.
Artigo em Inglês | MEDLINE | ID: mdl-35678602

RESUMO

SARS-CoV-2 spike (S) envelope glycoprotein constitutes the main determinant of virus entry and the target of host immune response, thus being of great interest for antiviral research. It is constituted of S1 and S2 subunits, which are involved in ACE2 receptor binding and fusion between the viral envelope and host cell membrane, respectively. Induction of the fusion process requires S cleavage at the S1-S2 junction and the S2' site located upstream of the fusion peptide. Interestingly, the SARS-CoV-2 spike harbors a 4-residue insertion at the S1-S2 junction that is absent in its closest relatives and constitutes a polybasic motif recognized by furin-like proteases. In addition, the S2' site is characterized by the presence of conserved basic residues. Here, we sought to determine the importance of the furin cleavage site (FCS) and the S2' basic residues for S-mediated entry functions. We determined the impact of mutations introduced at these sites on S processing, fusogenic activity, and its ability to mediate entry in different cellular backgrounds. Strikingly, mutation phenotypes were highly dependent on the host cell background. We confirmed that although the FCS was not absolutely required for virus entry, it contributed to extending the fusogenic potential of S. Cleavage site mutations, as well as inhibition of furin protease activity, affected the cell surface expression of S in a host cell-dependent manner. Finally, inhibition of furin activity differentially affected SARS-CoV-2 virus infectivity in the tested host cells, thereby confirming the host cell-dependent effect of spike processing for the viral life cycle. IMPORTANCE SARS-CoV-2 is responsible for the current global pandemic that has resulted in several million deaths. As the key determinant of virus entry into host cells and the main target of host immune response, the spike glycoprotein constitutes an attractive target for therapeutics development. Entry functions of spike rely on its processing at two sites by host cell proteases. While SARS-CoV-2 spike differs from its closest relatives by the insertion of a basic furin cleavage motif at the first site, it harbors conserved basic residues at the second cleavage site. Characterization of the importance of the basic sequences present at the two cleavage sites revealed that they were influencing spike processing, intracellular localization, induction of fusion, and entry in a host cell-dependent manner. Thus, our results revealed a high heterogeneity in spike sequence requirement for entry functions in the different host cells, in agreement with the high adaptability of the SARS-CoV-2 virus.


Assuntos
COVID-19 , Furina , SARS-CoV-2 , Glicoproteína da Espícula de Coronavírus , Internalização do Vírus , COVID-19/virologia , Furina/metabolismo , Humanos , SARS-CoV-2/genética , SARS-CoV-2/metabolismo , Glicoproteína da Espícula de Coronavírus/metabolismo
19.
Cell Mol Life Sci ; 79(7): 365, 2022 Jun 16.
Artigo em Inglês | MEDLINE | ID: mdl-35708858

RESUMO

SARS-CoV-2, although not being a circulatory virus, spread from the respiratory tract resulting in multiorgan failures and thrombotic complications, the hallmarks of fatal COVID-19. A convergent contributor could be platelets that beyond hemostatic functions can carry infectious viruses. Here, we profiled 52 patients with severe COVID-19 and demonstrated that circulating platelets of 19 out 20 non-survivor patients contain SARS-CoV-2 in robust correlation with fatal outcome. Platelets containing SARS-CoV-2 might originate from bone marrow and lung megakaryocytes (MKs), the platelet precursors, which were found infected by SARS-CoV-2 in COVID-19 autopsies. Accordingly, MKs undergoing shortened differentiation and expressing anti-viral IFITM1 and IFITM3 RNA as a sign of viral sensing were enriched in the circulation of deadly COVID-19. Infected MKs reach the lung concomitant with a specific MK-related cytokine storm rich in VEGF, PDGF and inflammatory molecules, anticipating fatal outcome. Lung macrophages capture SARS-CoV-2-containing platelets in vivo. The virus contained by platelets is infectious as capture of platelets carrying SARS-CoV-2 propagates infection to macrophages in vitro, in a process blocked by an anti-GPIIbIIIa drug. Altogether, platelets containing infectious SARS-CoV-2  alter COVID-19 pathogenesis and provide a powerful fatality marker. Clinical targeting of platelets might prevent viral spread, thrombus formation and exacerbated inflammation at once and increase survival in COVID-19.


Assuntos
COVID-19 , Trombose , Plaquetas , Humanos , Pulmão , Megacariócitos , Proteínas de Membrana , Proteínas de Ligação a RNA , SARS-CoV-2
20.
J Minim Invasive Gynecol ; 29(9): 1036, 2022 09.
Artigo em Inglês | MEDLINE | ID: mdl-35750194

RESUMO

STUDY OBJECTIVE: To demonstrate a new wet-lab model for training in conservative bowel endometriosis surgery (shaving and discoid resection). DESIGN: Video demonstration. MATERIALS AND METHODS: (1) Modeling deep infiltrating endometriosis using cryopreserved porcine rectum. (2) Conservative resection (shaving and discoid resection) using cold scissor and carbon dioxide laser (free beam and fiber). (3) Discoid resection. RESULTS: In this video, we present a new training model for improving the surgical management of bowel endometriosis. After dissection of the serosa and muscular layers, a modified biological glue is injected into the porcine rectum to accurately simulate an infiltrating bowel endometriosis lesion. Once dried, the simulated lesion can be resected using conventional laparoscopic instruments (cold scissors) or using more advanced techniques such as carbon dioxide laser, free beam and fiber (Storz and Lumenis). In case of bowel perforation during resection, this model enables realistic suturing. CONCLUSION: This new and highly realistic model allows the next generation of endometriosis surgeons to acquire adequate training to make bowel surgery safer and more effective.


Assuntos
Procedimentos Cirúrgicos do Sistema Digestório , Endometriose , Laparoscopia , Doenças Retais , Procedimentos Cirúrgicos do Sistema Digestório/métodos , Endometriose/patologia , Endometriose/cirurgia , Feminino , Humanos , Laparoscopia/métodos , Doenças Retais/cirurgia , Reto/cirurgia , Resultado do Tratamento
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA