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1.
J Med Virol ; 96(5): e29642, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38708812

RESUMO

Molnupiravir, an oral direct-acting antiviral effective in vitro against SARS-CoV-2, has been largely employed during the COVID-19 pandemic, since December 2021. After marketing and widespread usage, a progressive increase in SARS-CoV-2 lineages characterized by a higher transition/transversion ratio, a characteristic signature of molnupiravir action, appeared in the Global Initiative on Sharing All Influenza Data (GISAID) and International Nucleotide Sequence Database Collaboration (INSDC) databases. Here, we assessed the drug effects by SARS-CoV-2 whole-genome sequencing on 38 molnupiravir-treated persistently positive COVID-19 outpatients tested before and after treatment. Seventeen tixagevimab/cilgavimab-treated outpatients served as controls. Mutational analyses confirmed that SARS-CoV-2 exhibits an increased transition/transversion ratio seven days after initiation of molnupiravir. Moreover we observed an increased G->A ratio compared to controls, which was not related to apolipoprotein B mRNAediting enzyme, catalytic polypeptide-like (APOBEC) activity. In addition, we demonstrated for the first time an increased diversity and complexity of the viral quasispecies.


Assuntos
Antivirais , Tratamento Farmacológico da COVID-19 , Citidina/análogos & derivados , Genoma Viral , Hidroxilaminas , SARS-CoV-2 , Humanos , SARS-CoV-2/genética , SARS-CoV-2/efeitos dos fármacos , Antivirais/uso terapêutico , Antivirais/farmacologia , Hidroxilaminas/farmacologia , Hidroxilaminas/uso terapêutico , Masculino , Feminino , Estudos de Casos e Controles , Pessoa de Meia-Idade , Citidina/uso terapêutico , Citidina/farmacologia , Idoso , Adulto , Sequenciamento Completo do Genoma , Variação Genética , Uridina/farmacologia , COVID-19/virologia , Mutação
2.
J Med Virol ; 95(5): e28791, 2023 05.
Artigo em Inglês | MEDLINE | ID: mdl-37226579

RESUMO

Whole-genome sequencing (WGS) has been widely used for the genomic characterization and the phylogenesis of mpox virus (MPXV) 2022 multi-country outbreak. To date, no evidence has been reported on intra-host evolution within samples collected over time from a single patient with long-term infection. Fifty-one samples were collected from five patients at different time points post-symptom onset. All samples were confirmed as MPXV DNA positive, amplified by a multiplexed PCR amplicon, and sequenced by WGS. Complete MPXV genomes were assembled by reference mapping and then aligned to perform phylogenetic and hierarchical clustering analysis. Large intra-host variability was observed among the MPXV genomes sequenced from samples of two immunocompromised with advanced HIV-1 infection patients with prolonged MPXV shedding. Overall, 20 nucleotide mutations were identified in the 32 genomes from HIV patients, differently distributed in samples collected from different tissues and at different time points. No sequence compartmentalization nor variation was observed in the three patients with rapid viral clearance. MPXV exhibits adaptation to changing environments within the infected host and consequently demonstrates tissue compartmentalization. Further studies are needed to elucidate the role of this adaptation in forming a pool of genetic variability and contributing to viral persistence and its clinical implications.


Assuntos
Infecções por HIV , Mpox , Humanos , Filogenia , Genoma Viral , Análise por Conglomerados
3.
J Med Virol ; 95(6): e28831, 2023 06.
Artigo em Inglês | MEDLINE | ID: mdl-37246793

RESUMO

Despite the higher transmissibility of Omicron Variant of Concern (VOC), several reports have suggested lower risk for hospitalization and severe outcomes compared to previous variants of SARS-CoV-2. This study, enrolling all COVID-19 adults admitted to a reference hospital who underwent both the S-gene-target-failure test and VOC identification by Sanger sequencing, aimed to describe the evolving prevalence of Delta and Omicron variants and to compare the main in-hospital outcomes of severity, during a trimester (December 2021 to March 2022) of VOCs' cocirculation. Factors associated with clinical progression to noninvasive ventilation (NIV)/mechanical ventilation (MV)/death within 10 days and to MV/admission to intensive care unit (ICU)/death within 28 days, were investigated through multivariable logistic regressions. Overall, VOCs were: Delta n = 130/428, Omicron n = 298/428 (sublineages BA.1 n = 275 and BA.2 n = 23). Until mid-February, Delta predominance shifted to BA.1, which was gradually displaced by BA.2 until mid-March. Participants with Omicron VOC were more likely to be older, fully vaccinated, with multiple comorbidities and to have a shorter time from symptoms' onset, and less likely to have systemic symptoms and respiratory complications. Although the need of NIV within 10 days and MV within 28 days from hospitalization and the admission to ICU were less frequent for patients with Omicron compared to those with Delta infections, mortality was similar between the two VOCs. In the adjusted analysis, multiple comorbidities and a longer time from symptoms' onset predicted 10-day clinical progression, while complete vaccination halved the risk. Multimorbidity was the only risk factor associated with 28-day clinical progression. In our population, in the first trimester of 2022, Omicron rapidly displaced Delta in COVID-19 hospitalized adults. Clinical profile and presentation differed between the two VOCs and, although Omicron infections showed a less severe clinical picture, no substantial differences for clinical progression were found. This finding suggests that any hospitalization, especially in more vulnerable individuals, may be at risk for severe progression, which is more related to the underlying frailty of patients than to the intrinsic severity of the viral variant.


Assuntos
COVID-19 , SARS-CoV-2 , Adulto , Humanos , SARS-CoV-2/genética , COVID-19/epidemiologia , Hospitais , Progressão da Doença
4.
Euro Surveill ; 28(2)2023 01.
Artigo em Inglês | MEDLINE | ID: mdl-36695479

RESUMO

With numbers of COVID-19 cases having substantially increased at the end of 2022 in China, some countries have started or expanded testing and genomic surveillance of travellers. We report screening results in Italy in late December 2022 of 556 flight passengers in provenance from two Chinese provinces. Among these passengers, 126 (22.7%) tested SARS-CoV-2 positive. Whole genome sequencing of 61 passengers' positive samples revealed Omicron variants, notably sub-lineages BA.5.2.48, BF.7.14 and BQ.1.1, in line with data released from China.


Assuntos
COVID-19 , SARS-CoV-2 , Humanos , SARS-CoV-2/genética , COVID-19/epidemiologia , Genômica , China/epidemiologia , Itália/epidemiologia
5.
Euro Surveill ; 28(44)2023 11.
Artigo em Inglês | MEDLINE | ID: mdl-37917030

RESUMO

Between August and September 2023, three distinct autochthonous dengue virus transmission events occurred in Lazio, Italy, with the main event in Rome. The events involved three different dengue serotypes. No link with previous imported cases was identified. Here we describe the epidemiological and phylogenetic analysis of the first autochthonous cases and the implemented control actions. The multiple transmission events call for a strengthening of the vector control strategies and future research to better characterise the risk in countries like Italy.


Assuntos
Dengue , Surtos de Doenças , Humanos , Filogenia , Itália/epidemiologia , Sorogrupo , Dengue/epidemiologia
6.
Virol J ; 19(1): 4, 2022 01 06.
Artigo em Inglês | MEDLINE | ID: mdl-34991646

RESUMO

INTRODUCTION: Transplantation among HIV positive patients may be a valuable therapeutic intervention. This study involves an HIV D+/R+ kidney-liver transplantation, where PBMC-associated HIV quasispecies were analyzed in donor and transplant recipients (TR) prior to transplantation and thereafter, together with standard viral monitoring. METHODS: The donor was a 54 year of age HIV infected woman: kidney and liver recipients were two HIV infected men, aged 49 and 61. HIV quasispecies in PBMC was analyzed by ultra-deep sequencing of V3 env region. During TR follow-up, plasma HIV-1 RNA, HIV-1 DNA in PBMC, analysis of proviral integration sites and drug-resistance genotyping were performed. Other virological and immunological monitoring included CMV and EBV DNA quantification in blood and CD4 T cell counts. RESULTS: Donor and TR were all ART-HIV suppressed at transplantation. Thereafter, TR maintained a nearly suppressed HIV-1 viremia, but HIV-1 RNA blips and the increase of proviral integration sites in PBMC attested some residual HIV replication. A transient peak in HIV-1 DNA occurred in the liver recipient. No major changes of drug-resistance genotype were detected after transplantation. CMV and EBV transient reactivations were observed only in the kidney recipient, but did not require specific treatment. CD4 counts remained stable. No intermixed quasispecies between donor and TR was observed at transplantation or thereafter. Despite signs of viral evolution in TR, HIV genetic heterogeneity did not increase over the course of the months of follow up. CONCLUSIONS: No evidence of HIV superinfection was observed in the donor nor in the recipients. The immunosuppressive treatment administrated to TR did not result in clinical relevant viral reactivations.


Assuntos
Infecções por HIV , Transplante de Fígado , Humanos , Rim , Leucócitos Mononucleares , Fígado , Quase-Espécies
7.
Euro Surveill ; 27(22)2022 06.
Artigo em Inglês | MEDLINE | ID: mdl-35656836

RESUMO

Since May 2022, an outbreak of monkeypox has been ongoing in non-endemic countries. We report four cases in Italy in young adult men reporting condomless sexual intercourse. The patients are in good clinical condition with no need for specific antiviral drugs. Biological samples from seminal fluid were positive for monkeypox viral DNA. For many other viruses found in semen there is no evidence of sexual transmission. The possibility of sexual transmission of monkeypox virus needs to be investigated.


Assuntos
Mpox , Comportamento Sexual , Surtos de Doenças , Humanos , Masculino , Mpox/epidemiologia , Mpox/transmissão , Monkeypox virus , Sêmen , Adulto Jovem
8.
Int J Mol Sci ; 23(21)2022 Oct 28.
Artigo em Inglês | MEDLINE | ID: mdl-36361870

RESUMO

A large number of SARS-CoV-2 mutations in a short period of time has driven scientific research related to vaccines, new drugs, and antibodies to combat the new variants of the virus. Herein, we present a web portal containing the structural information, the tridimensional coordinates, and the molecular dynamics trajectories of the SARS-CoV-2 spike protein and its main variants. The Spike Mutants website can serve as a rapid online tool for investigating the impact of novel mutations on virus fitness. Taking into account the high variability of SARS-CoV-2, this application can help the scientific community when prioritizing molecules for experimental assays, thus, accelerating the identification of promising drug candidates for COVID-19 treatment. Below we describe the main features of the platform and illustrate the possible applications for speeding up the drug discovery process and hypothesize new effective strategies to overcome the recurrent mutations in SARS-CoV-2 genome.


Assuntos
COVID-19 , SARS-CoV-2 , Humanos , SARS-CoV-2/genética , Glicoproteína da Espícula de Coronavírus/metabolismo , Mutação , Tratamento Farmacológico da COVID-19
9.
Int J Mol Sci ; 23(15)2022 Aug 04.
Artigo em Inglês | MEDLINE | ID: mdl-35955815

RESUMO

The vast amount of epidemiologic and genomic data that were gathered as a global response to the COVID-19 pandemic that was caused by SARS-CoV-2 offer a unique opportunity to shed light on the structural evolution of coronaviruses and in particular on the spike (S) glycoprotein, which mediates virus entry into the host cell by binding to the human ACE2 receptor. Herein, we carry out an investigation into the dynamic properties of the S glycoprotein, focusing on the much more transmissible Delta and Omicron variants. Notwithstanding the great number of mutations that have accumulated, particularly in the Omicron S glycoprotein, our data clearly showed the conservation of some structural and dynamic elements, such as the global motion of the receptor binding domain (RBD). However, our studies also revealed structural and dynamic alterations that were concentrated in the aa 627-635 region, on a small region of the receptor binding motif (aa 483-485), and the so-called "fusion-peptide proximal region". In particular, these last two S regions are known to be involved in the human receptor ACE2 recognition and membrane fusion. Our structural evidence, therefore, is likely involved in the observed different transmissibility of these S mutants. Finally, we highlighted the role of glycans in the increased RBD flexibility of the monomer in the up conformation of Omicron.


Assuntos
COVID-19 , Glicoproteína da Espícula de Coronavírus , Enzima de Conversão de Angiotensina 2/genética , COVID-19/genética , Glicoproteínas , Humanos , Mutação , Pandemias , SARS-CoV-2/genética , Glicoproteína da Espícula de Coronavírus/metabolismo
10.
Emerg Infect Dis ; 26(8): 1842-1845, 2020 08.
Artigo em Inglês | MEDLINE | ID: mdl-32459984
11.
Cytokine ; 125: 154839, 2020 01.
Artigo em Inglês | MEDLINE | ID: mdl-31542514

RESUMO

Antiretroviral treatment (ART) of Primary HIV Infection (PHI) has demonstrated virological and immunological benefits. The effect of early ART during PHI on the level of growth factors and chemokines modulating immune cell functions remains to be established. The aim of our work was to analyze the dynamics of 27 cytokines, chemokines and growth/regulation factors in plasma of HIV infected patients treated during PHI. Patients with PHI (n = 43) were enrolled before, 24 and 48 weeks after therapy initiation. Quantification of soluble immune mediators was performed in plasma from HIV infected patients and healthy donors (HD, n = 7) by Luminex technology. The cytokines profile was strongly perturbed in primary HIV infected patients when compared to healthy donors (HD). After 48 weeks of ART, some of these factors were restored to HD level (IL-2, IL-5, IL-7, IL-9, IL12p70, TNFα) while others persisted higher than HD (IL-6, IL-10, IL-13). Interestingly, a subset of chemokines, such as IL-8, MCP-1, RANTES and CCL27, and growth factors such as HGF, SCF and GM-CSF, increased during ART, reaching values significantly higher than HD after 48 weeks. Moreover, the G-CSF and MIP-1ß soluble mediators were persistently altered and showed an inverse correlation with the CD4/CD8 T cell ratio. The increase of chemokines with antiviral activity and of growth factors with hematopoietic and immunomodulatory properties may have beneficial effects. Other studies are mandatory to evaluate the effects of long lasting levels of these factors to clarify their possible role in the context of protection/pathogenesis.


Assuntos
Antirretrovirais/uso terapêutico , Quimiocinas/sangue , Citocinas/sangue , Infecções por HIV/sangue , Infecções por HIV/tratamento farmacológico , Peptídeos e Proteínas de Sinalização Intercelular/metabolismo , Terapia Antirretroviral de Alta Atividade , Linfócitos T CD4-Positivos/citologia , Linfócitos T CD4-Positivos/imunologia , Linfócitos T CD8-Positivos/citologia , Linfócitos T CD8-Positivos/imunologia , Quimiocina CCL2/sangue , Quimiocina CCL27/sangue , Quimiocina CCL5/sangue , Regulação para Baixo , Fator Estimulador de Colônias de Granulócitos/sangue , Fator Estimulador de Colônias de Granulócitos e Macrófagos/sangue , Fator de Crescimento de Hepatócito/sangue , Humanos , Interleucina-10/sangue , Interleucina-12/sangue , Interleucina-13/sangue , Interleucina-2/sangue , Interleucina-5/sangue , Interleucina-7/sangue , Interleucina-8/sangue , Análise de Componente Principal , Fator de Células-Tronco/sangue , Fator de Necrose Tumoral alfa/sangue
13.
Euro Surveill ; 24(5)2019 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-30722811

RESUMO

BackgroundCrimean-Congo haemorrhagic fever virus (CCHFV) is considered an emerging infectious disease threat in the European Union. Since 2000, the incidence and geographic range of confirmed CCHF cases have markedly increased, following changes in the distribution of its main vector, Hyalomma ticks.AimsTo review scientific literature and collect experts' opinion to analyse relevant aspects of the laboratory management of human CCHF cases and any exposed contacts, as well as identify areas for advancement of international collaborative preparedness and laboratory response plans.MethodsWe conducted a literature review on CCHF molecular diagnostics through an online search. Further, we obtained expert opinions on the key laboratory aspects of CCHF diagnosis. Consulted experts were members of two European projects, EMERGE (Efficient response to highly dangerous and emerging pathogens at EU level) and EVD-LabNet (Emerging Viral Diseases-Expert Laboratory Network).ResultsConsensus was reached on relevant and controversial aspects of CCHF disease with implications for laboratory management of human CCHF cases, including biosafety, diagnostic algorithm and advice to improve lab capabilities. Knowledge on the diffusion of CCHF can be obtained by promoting syndromic approach to infectious diseases diagnosis and by including CCHFV infection in the diagnostic algorithm of severe fevers of unknown origin.ConclusionNo effective vaccine and/or therapeutics are available at present so outbreak response relies on rapid identification and appropriate infection control measures. Frontline hospitals and reference laboratories have a crucial role in the response to a CCHF outbreak, which should integrate laboratory, clinical and public health responses.


Assuntos
Técnicas de Laboratório Clínico/métodos , DNA Viral/genética , Vírus da Febre Hemorrágica da Crimeia-Congo/genética , Vírus da Febre Hemorrágica da Crimeia-Congo/isolamento & purificação , Febre Hemorrágica da Crimeia/diagnóstico , Febre Hemorrágica da Crimeia/transmissão , Ensaio de Proficiência Laboratorial/normas , Animais , Doenças Transmissíveis Emergentes/epidemiologia , DNA Viral/análise , Surtos de Doenças/prevenção & controle , Ensaio de Imunoadsorção Enzimática , Vírus da Febre Hemorrágica da Crimeia-Congo/imunologia , Febre Hemorrágica da Crimeia/epidemiologia , Febre Hemorrágica da Crimeia/virologia , Humanos , Imunoglobulina G/sangue , Ixodidae , Laboratórios , Ensaio de Proficiência Laboratorial/métodos , Análise de Sequência de RNA , Carrapatos/virologia
14.
Emerg Infect Dis ; 23(12): 1941-1949, 2017 12.
Artigo em Inglês | MEDLINE | ID: mdl-28975882

RESUMO

In January 2015, during a 3-week period, 12 captive Tonkean macacques at a sanctuary in Italy died. An orthopoxvirus infection was suspected because of negative-staining electron microscopy results. The diagnosis was confirmed by histology, virus isolation, and molecular analysis performed on different organs from all animals. An epidemiologic investigation was unable to define the infection source in the surrounding area. Trapped rodents were negative by virologic testing, but specific IgG was detected in 27.27% of small rodents and 14.28% of rats. An attenuated live vaccine was administered to the susceptible monkey population, and no adverse reactions were observed; a detectable humoral immune response was induced in most of the vaccinated animals. We performed molecular characterization of the orthopoxvirus isolate by next-generation sequencing. According to the phylogenetic analysis of the 9 conserved genes, the virus could be part of a novel clade, lying between cowpox and ectromelia viruses.


Assuntos
Surtos de Doenças , Doenças dos Macacos/epidemiologia , Orthopoxvirus/genética , Filogenia , Infecções por Poxviridae/epidemiologia , Infecções por Poxviridae/veterinária , Animais , Anticorpos Antivirais/sangue , Abrigo para Animais , Imunidade Humoral/efeitos dos fármacos , Imunoglobulina G/sangue , Itália/epidemiologia , Macaca , Masculino , Doenças dos Macacos/imunologia , Doenças dos Macacos/mortalidade , Doenças dos Macacos/prevenção & controle , Orthopoxvirus/classificação , Orthopoxvirus/isolamento & purificação , Orthopoxvirus/patogenicidade , Infecções por Poxviridae/mortalidade , Infecções por Poxviridae/prevenção & controle , Ratos , Roedores/virologia , Pele/patologia , Pele/virologia , Análise de Sobrevida , Vacinação , Vacinas Virais/administração & dosagem
15.
Viruses ; 16(7)2024 Jun 24.
Artigo em Inglês | MEDLINE | ID: mdl-39066176

RESUMO

Enteroviruses (EVs) are ubiquitous viruses that circulate worldwide, causing sporadic or epidemic infections, typically during the summer and fall. They cause a broad spectrum of illnesses, ranging from an unspecified febrile clinical presentation to a severe illness. EVs are recognized to be the most frequent etiological agents of aseptic meningitis in children. However, as the infection is usually mild and self-limiting, it remains underestimated, and the epidemiology of EVs is poorly understood. To date, no vaccine or effective therapy for all types of enteroviruses is available, and EVs constitute a public health concern. Here, we investigated the molecular epidemiology of EV strains circulating in the Lazio region over a 10-year time span (2012-2023) by using a sequence-typing approach and phylogenetic analysis. The epidemiological trend of EV infection has undergone changes during the SARS-CoV-2 pandemic (2020-2021), which resulted in a modification in terms of the number of diagnosed cases and seasonality. From 2022, the circulation of EVs showed a behavior typical of the pre-pandemic period, although changes in predominantly circulating strains have been noted. Both epidemic and sporadic circulation events have been characterized in the Lazio region. Further analyses are needed to better characterize any strain with higher potential pathogenic power and to identify possible recombinant strains.


Assuntos
Infecções por Enterovirus , Enterovirus , Genótipo , Epidemiologia Molecular , Filogenia , Humanos , Infecções por Enterovirus/virologia , Infecções por Enterovirus/epidemiologia , Enterovirus/genética , Enterovirus/classificação , Enterovirus/isolamento & purificação , Estações do Ano , COVID-19/epidemiologia , COVID-19/virologia , SARS-CoV-2/genética , SARS-CoV-2/classificação , Criança
16.
BMC Vet Res ; 9: 122, 2013 Jun 19.
Artigo em Inglês | MEDLINE | ID: mdl-23782433

RESUMO

BACKGROUND: Bovine Spastic Paresis (BSP) is a neuromuscular disorder which affects both male and female cattle. BSP is characterized by spastic contraction and overextension of the gastrocnemious muscle of one or both limbs and is associated with a scarce increase in body weight. This disease seems to be caused by an autosomal and recessive gene, with incomplete penetration, although no genes clearly involved with its onset have been so far identified. We employed cDNA microarrays to identify metabolic pathways affected by BSP in Romagnola cattle breed. Investigation of those pathways at the genome level can help to understand this disease. RESULTS: Microarray analysis of control and affected individuals resulted in 268 differentially expressed genes. These genes were subjected to KEGG pathway functional clustering analysis, revealing that they are predominantly involved in Cell Communication, Signalling Molecules and Interaction and Signal Transduction, Diseases and Nervous System classes. Significantly enriched KEGG pathway's classes for the differentially expressed genes were calculated; interestingly, all those significantly under-expressed in the affected samples are included in Neurodegenerative Diseases. To identify genome locations possibly harbouring gene(s) involved in the disease, the chromosome distribution of the differentially expressed genes was also investigated. CONCLUSIONS: The cDNA microarray we used in this study contains a brain library and, even if carrying an incomplete transcriptome representation, it has proven to be a valuable tool allowing us to add useful and new information to a poorly studied disease. By using this tool, we examined nearly 15000 transcripts and analysed gene pathways affected by the disease. Particularly, our data suggest also a defective glycinergic synaptic transmission in the development of the disease and an alteration of calcium signalling proteins. We provide data to acquire knowledge of a genetic disease for which literature still presents poor results and that could be further and specifically analysed in the next future. Moreover this study, performed in livestock, may also harbour molecular information useful for understanding human diseases.


Assuntos
Doenças dos Bovinos/metabolismo , Perfilação da Expressão Gênica/veterinária , Sistema Nervoso/metabolismo , Análise de Sequência com Séries de Oligonucleotídeos/veterinária , Paraparesia Espástica/veterinária , Animais , Bovinos , Doenças dos Bovinos/genética , Feminino , Expressão Gênica/genética , Masculino , Paraparesia Espástica/genética , Paraparesia Espástica/metabolismo , Reação em Cadeia da Polimerase em Tempo Real/veterinária , ATPases Transportadoras de Cálcio do Retículo Sarcoplasmático/genética
17.
Diagnostics (Basel) ; 13(9)2023 Apr 27.
Artigo em Inglês | MEDLINE | ID: mdl-37174964

RESUMO

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is characterized by fast evolution with the appearance of several variants. Next-Generation Sequencing (NGS) technology is considered the gold standard for monitoring known and new SARS-CoV-2 variants. However, the complexity of this technology renders this approach impracticable in laboratories located in areas with limited resources. We analyzed the capability of the ThermoFisher TaqPath COVID-19 RT-PCR (TaqPath) and the Seegene Novaplex SARS-CoV-2 Variant assay (Novaplex) to detect Omicron variants; the Allplex VariantII (Allplex) was also evaluated for Delta variants. Sanger sequencing (SaS) was the reference method. The results obtained with n = 355 nasopharyngeal samples were: negative with TaqPath, although positive with other qualitative molecular assays (n = 35); undetermined (n = 40) with both the assays; negative for the ∆69/70 mutation and confirmed as the Delta variant via SaS (n = 100); positive for ∆69/70 and confirmed as Omicron BA.1 via SaS (n = 80); negative for ∆69/70 and typed as Omicron BA.2 via SaS (n = 80). Novaplex typed 27.5% of samples as undetermined with TaqPath, 11.4% of samples as negative with TaqPath, and confirmed 100% of samples were Omicron subtypes. In total, 99/100 samples were confirmed as the Delta variant with Allplex with a positive per cent agreement (PPA) of 98% compared to SaS. As undermined samples with Novaplex showed RdRp median Ct values (Ct = 35.4) statistically higher than those of typed samples (median Ct value = 22.0; p < 0.0001, Mann-Whitney test), the inability to establish SARS-CoV-2 variants was probably linked to the low viral load. No amplification was obtained with SaS among all 35 negative TaqPath samples. Overall, 20% of samples which were typed as negative or undetermined with TaqPath, and among them, twelve were not typed even by SaS, but they were instead correctly identified with Novaplex. Although full-genome sequencing remains the elected method to characterize new strains, our data show the high ability of a SNP-based assay to identify VOCs, also resolving samples typed as undetermined with TaqPath.

18.
Viruses ; 15(11)2023 Oct 31.
Artigo em Inglês | MEDLINE | ID: mdl-38005872

RESUMO

Since the beginning of the COVID-19 pandemic, large-scale genomic sequencing has immediately pointed out that SARS-CoV-2 has rapidly mutated during the course of the pandemic, resulting in the emergence of variants with a public health impact. In this context, strictly monitoring the circulating strains via NGS has proven to be crucial for the early identification of new emerging variants and the study of the genomic evolution and transmission of SARS-CoV-2. Following national and international guidelines, the Lazio region has created a sequencing laboratory network (WGSnet-Lazio) that works in synergy with the reference center for epidemiological surveillance (SERESMI) to monitor the circulation of SARS-CoV-2. Sequencing was carried out with the aims of characterizing outbreak transmission dynamics, performing the genomic analysis of viruses infecting specific categories of patients (i.e., immune-depressed, travelers, and people with severe symptoms) and randomly monitoring variant circulation. Here we report data emerging from sequencing activities carried out by WGSnet-Lazio (from February 2020 to October 2022) linked with epidemiological data to correlate the circulation of variants with the clinical and demographic characteristics of patients. The model of the sequencing network developed in the Lazio region proved to be a useful tool for SARS-CoV-2 surveillance and to support public health measures for epidemic containment.


Assuntos
COVID-19 , SARS-CoV-2 , Humanos , SARS-CoV-2/genética , Pandemias , COVID-19/epidemiologia , Genômica , Monitoramento Epidemiológico , Itália/epidemiologia
19.
Biomolecules ; 13(10)2023 10 18.
Artigo em Inglês | MEDLINE | ID: mdl-37892220

RESUMO

Mutations in the SARS-CoV-2 Spike glycoprotein can affect monoclonal antibody efficacy. Recent findings report the occurrence of resistant mutations in immunocompromised patients after tixagevimab/cilgavimab treatment. More recently, the Food and Drug Agency revoked the authorization for tixagevimab/cilgavimab, while this monoclonal antibody cocktail is currently recommended by the European Medical Agency. We retrospectively reviewed 22 immunocompetent patients at high risk for disease progression who received intramuscular tixagevimab/cilgavimab as early COVID-19 treatment and presented a prolonged high viral load. Complete SARS-CoV-2 genome sequences were obtained for a deep investigation of mutation frequencies in Spike protein before and during treatment. At seven days, only one patient showed evidence of treatment-emergent cilgavimab resistance. Quasispecies analysis revealed two different deletions on the Spike protein (S:del138-144 or S:del141-145) in combination with the resistance S:K444N mutation. The structural and dynamic impact of the two quasispecies was characterized by using molecular dynamics simulations, showing the conservation of the principal functional movements in the mutated systems and their capabilities to alter the structure and dynamics of the RBD, responsible for the interaction with the ACE2 human receptor. Our study underlines the importance of prompting an early virological investigation to prevent drug resistance or clinical failures in immunocompetent patients.


Assuntos
Pacientes Ambulatoriais , Glicoproteína da Espícula de Coronavírus , Humanos , Glicoproteína da Espícula de Coronavírus/genética , Tratamento Farmacológico da COVID-19 , Estudos Retrospectivos , Anticorpos Monoclonais
20.
Microorganisms ; 11(11)2023 Oct 27.
Artigo em Inglês | MEDLINE | ID: mdl-38004656

RESUMO

The SARS-CoV-2 Delta variant of concern (VOC) was often associated with serious clinical course of the COVID-19 disease. Herein, we investigated the selective pressure, gene flow and evaluation on the frequencies of mutations causing amino acid substitutions in the Delta variant in three Italian regions. A total of 1500 SARS-CoV-2 Delta genomes, collected in Italy from April to October 2021 were investigated, including a subset of 596 from three Italian regions. The selective pressure and the frequency of amino acid substitutions and the prediction of their possible impact on the stability of the proteins were investigated. Delta variant dataset, in this study, identified 68 sites under positive selection: 16 in the spike (23.5%), 11 in nsp2 (16.2%) and 10 in nsp12 (14.7%) genes. Three of the positive sites in the spike were located in the receptor-binding domain (RBD). In Delta genomes from the three regions, 6 changes were identified as very common (>83.7%), 4 as common (>64.0%), 21 at low frequency (2.1%-25.0%) and 29 rare (≤2.0%). The detection of positive selection on key mutations may represent a model to identify recurrent signature mutations of the virus.

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