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1.
Cell Discov ; 10(1): 14, 2024 Feb 06.
Artículo en Inglés | MEDLINE | ID: mdl-38320990

RESUMEN

The current SARS-CoV-2 variants strikingly evade all authorized monoclonal antibodies and threaten the efficacy of serum-neutralizing activity elicited by vaccination or prior infection, urging the need to develop antivirals against SARS-CoV-2 and related sarbecoviruses. Here, we identified both potent and broadly neutralizing antibodies from a five-dose vaccinated donor who exhibited cross-reactive serum-neutralizing activity against diverse coronaviruses. Through single B-cell sorting and sequencing followed by a tailor-made computational pipeline, we successfully selected 86 antibodies with potential cross-neutralizing ability from 684 antibody sequences. Among them, PW5-570 potently neutralized all SARS-CoV-2 variants that arose prior to Omicron BA.5, and the other three could broadly neutralize all current SARS-CoV-2 variants of concern, SARS-CoV and their related sarbecoviruses (Pangolin-GD, RaTG13, WIV-1, and SHC014). Cryo-EM analysis demonstrates that these antibodies have diverse neutralization mechanisms, such as disassembling spike trimers, or binding to RBM or SD1 to affect ACE2 binding. In addition, prophylactic administration of these antibodies significantly protects nasal turbinate and lung infections against BA.1, XBB.1, and SARS-CoV viral challenge in golden Syrian hamsters, respectively. Importantly, post-exposure treatment with PW5-5 and PW5-535 also markedly protects against XBB.1 challenge in these models. This study reveals the potential utility of computational process to assist screening cross-reactive antibodies, as well as the potency of vaccine-induced broadly neutralizing antibodies against current SARS-CoV-2 variants and related sarbecoviruses, offering promising avenues for the development of broad therapeutic antibody drugs.

2.
J Med Virol ; 96(2): e29472, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-38373201

RESUMEN

Interferons (IFNs) are critical for immune defense against pathogens. While type-I and -III IFNs have been reported to inhibit SARS-CoV-2 replication, the antiviral effect and mechanism of type-II IFN against SARS-CoV-2 remain largely unknown. Here, we evaluate the antiviral activity of type-II IFN (IFNγ) using human lung epithelial cells (Calu3) and ex vivo human lung tissues. In this study, we found that IFNγ suppresses SARS-CoV-2 replication in both Calu3 cells and ex vivo human lung tissues. Moreover, IFNγ treatment does not significantly modulate the expression of SARS-CoV-2 entry-related factors and induces a similar level of pro-inflammatory response in human lung tissues when compared with IFNß treatment. Mechanistically, we show that overexpression of indoleamine 2,3-dioxygenase 1 (IDO1), which is most profoundly induced by IFNγ, substantially restricts the replication of ancestral SARS-CoV-2 and the Alpha and Delta variants. Meanwhile, loss-of-function study reveals that IDO1 knockdown restores SARS-CoV-2 replication restricted by IFNγ in Calu3 cells. We further found that the treatment of l-tryptophan, a substrate of IDO1, partially rescues the IFNγ-mediated inhibitory effect on SARS-CoV-2 replication in both Calu3 cells and ex vivo human lung tissues. Collectively, these results suggest that type-II IFN potently inhibits SARS-CoV-2 replication through IDO1-mediated antiviral response.


Asunto(s)
COVID-19 , SARS-CoV-2 , Humanos , SARS-CoV-2/metabolismo , Indolamina-Pirrol 2,3,-Dioxigenasa/genética , Replicación Viral , Pulmón , Interferones , Células Epiteliales , Antivirales/farmacología
4.
Nat Biomed Eng ; 8(3): 291-309, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-37996617

RESUMEN

Mapping mutations and discovering cellular determinants that cause the spike protein of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) to induce infected cells to form syncytia would facilitate the development of strategies for blocking the formation of such cell-cell fusion. Here we describe high-throughput screening methods based on droplet microfluidics and the size-exclusion selection of syncytia, coupled with large-scale mutagenesis and genome-wide knockout screening via clustered regularly interspaced short palindromic repeats (CRISPR), for the large-scale identification of determinants of cell-cell fusion. We used the methods to perform deep mutational scans in spike-presenting cells to pinpoint mutable syncytium-enhancing substitutions in two regions of the spike protein (the fusion peptide proximal region and the furin-cleavage site). We also used a genome-wide CRISPR screen in cells expressing the receptor angiotensin-converting enzyme 2 to identify inhibitors of clathrin-mediated endocytosis that impede syncytium formation, which we validated in hamsters infected with SARS-CoV-2. Finding genetic and cellular determinants of the formation of syncytia may reveal insights into the physiological and pathological consequences of cell-cell fusion.


Asunto(s)
COVID-19 , SARS-CoV-2 , Humanos , Ensayos Analíticos de Alto Rendimiento , Glicoproteína de la Espiga del Coronavirus/genética , COVID-19/patología , Células Gigantes/metabolismo , Células Gigantes/patología
5.
EBioMedicine ; 99: 104916, 2024 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-38101297

RESUMEN

BACKGROUND: Earlier Omicron subvariants including BA.1, BA.2, and BA.5 emerged in waves, with a subvariant replacing the previous one every few months. More recently, the post-BA.2/5 subvariants have acquired convergent substitutions in spike that facilitated their escape from humoral immunity and gained ACE2 binding capacity. However, the intrinsic pathogenicity and replication fitness of the evaluated post-BA.2/5 subvariants are not fully understood. METHODS: We systemically investigated the replication fitness and intrinsic pathogenicity of representative post-BA.2/5 subvariants (BL.1, BQ.1, BQ.1.1, XBB.1, CH.1.1, and XBB.1.5) in weanling (3-4 weeks), adult (8-10 weeks), and aged (10-12 months) mice. In addition, to better model Omicron replication in the human nasal epithelium, we further investigated the replication capacity of the post-BA.2/5 subvariants in human primary nasal epithelial cells. FINDINGS: We found that the evaluated post-BA.2/5 subvariants are consistently attenuated in mouse lungs but not in nasal turbinates when compared with their ancestral subvariants BA.2/5. Further investigations in primary human nasal epithelial cells revealed a gained replication fitness of XBB.1 and XBB.1.5 when compared to BA.2 and BA.5.2. INTERPRETATION: Our study revealed that the post-BA.2/5 subvariants are attenuated in lungs while increased in replication fitness in the nasal epithelium, indicating rapid adaptation of the circulating Omicron subvariants in the human populations. FUNDING: The full list of funding can be found at the Acknowledgements section.


Asunto(s)
COVID-19 , SARS-CoV-2 , Adulto , Humanos , Animales , Ratones , Virulencia , Células Epiteliales , Mucosa Nasal
6.
EBioMedicine ; 95: 104753, 2023 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-37579626

RESUMEN

BACKGROUND: Among the Omicron sublineages that have emerged, BA.1, BA.2, BA.5, and their related sublineages have resulted in the largest number of infections. While recent studies demonstrated that all Omicron sublineages robustly escape neutralizing antibody response, it remains unclear on whether these Omicron sublineages share any pattern of evolutionary trajectory on their replication efficiency and intrinsic pathogenicity along the respiratory tract. METHODS: We compared the virological features, replication capacity of dominant Omicron sublineages BA.1, BA.2 and BA.5 in the human nasal epithelium, and characterized their pathogenicity in K18-hACE2, A129, young C57BL/6, and aged C57BL/6 mice. FINDINGS: We found that BA.5 replicated most robustly, followed by BA.2 and BA.1, in the differentiated human nasal epithelium. Consistently, BA.5 infection resulted in higher viral gene copies, infectious viral titres and more abundant viral antigen expression in the nasal turbinates of the infected K18-hACE2 transgenic mice. In contrast, the Omicron sublineages are continuously attenuated in lungs of infected K18-hACE2 and C57BL/6 mice, leading to decreased pathogenicity. Nevertheless, lung manifestations remain severe in Omicron sublineages-infected A129 and aged C57BL/6 mice. INTERPRETATION: Our results suggested that the Omicron sublineages might be gaining intrinsic replication fitness in the upper respiratory tract, therefore highlighting the importance of global surveillance of the emergence of hyper-transmissive Omicron sublineages. On the contrary, replication and intrinsic pathogenicity of Omicron is suggested to be further attenuated in the lower respiratory tract. Effective vaccination and other precautions should be in place to prevent severe infections in the immunocompromised populations at risk. FUNDING: A full list of funding bodies that contributed to this study can be found in the Acknowledgements section.


Asunto(s)
COVID-19 , Ratones , Animales , Humanos , Anciano , Ratones Endogámicos C57BL , SARS-CoV-2 , Virulencia , Anticuerpos Neutralizantes , Ratones Transgénicos , Anticuerpos Antivirales
7.
Sci Adv ; 9(3): eadd3867, 2023 01 20.
Artículo en Inglés | MEDLINE | ID: mdl-36662861

RESUMEN

Successful severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection requires proteolytic cleavage of the viral spike protein. While the role of the host transmembrane protease serine 2 in SARS-CoV-2 infection is widely recognized, the involvement of other proteases capable of facilitating SARS-CoV-2 entry remains incompletely explored. Here, we show that multiple members from the membrane-type matrix metalloproteinase (MT-MMP) and a disintegrin and metalloproteinase families can mediate SARS-CoV-2 entry. Inhibition of MT-MMPs significantly reduces SARS-CoV-2 replication in vitro and in vivo. Mechanistically, we show that MT-MMPs can cleave SARS-CoV-2 spike and angiotensin-converting enzyme 2 and facilitate spike-mediated fusion. We further demonstrate that Omicron BA.1 has an increased efficiency on MT-MMP usage, while an altered efficiency on transmembrane serine protease usage for virus entry compared with that of ancestral SARS-CoV-2. These results reveal additional protease determinants for SARS-CoV-2 infection and enhance our understanding on the biology of coronavirus entry.


Asunto(s)
COVID-19 , SARS-CoV-2 , Humanos , SARS-CoV-2/metabolismo , Péptido Hidrolasas/metabolismo , Proteolisis , Metaloproteasas/metabolismo , Internalización del Virus
8.
Microb Pathog ; 173(Pt A): 105828, 2022 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-36243381

RESUMEN

The ongoing global pandemic of novel coronavirus pneumonia (COVID-19) caused by the SARS-CoV-2 has a significant impact on global health and economy system. In this context, there have been some landmark advances in vaccine development. Over 100 new coronavirus vaccine candidates have been approved for clinical trials, with ten WHO-approved vaccines including four inactivated virus vaccines, two mRNA vaccines, three recombinant viral vectored vaccines and one protein subunit vaccine on the "Emergency Use Listing". Although the SARS-CoV-2 has an internal proofreading mechanism, there have been a number of mutations emerged in the pandemic affecting its transmissibility, pathogenicity and immunogenicity. Of these, mutations in the spike (S) protein and the resultant mutant variants have posed new challenges for vaccine development and application. In this review article, we present an overview of vaccine development, the prevalence of new coronavirus variants and their impact on protective efficacy of existing vaccines and possible immunization strategies coping with the viral mutation and diversity.


Asunto(s)
Vacunas contra la COVID-19 , COVID-19 , SARS-CoV-2 , Humanos , Anticuerpos Antivirales , COVID-19/prevención & control , Inmunogenicidad Vacunal , Mutación , SARS-CoV-2/genética , Glicoproteína de la Espiga del Coronavirus/genética , Desarrollo de Vacunas , Vacunas de Productos Inactivados
9.
Cell Rep Med ; 3(9): 100743, 2022 09 20.
Artículo en Inglés | MEDLINE | ID: mdl-36084644

RESUMEN

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) Omicron BA.2 was a dominant circulating SARS-CoV-2 variant worldwide. Recent reports hint that BA.2 is similarly potent regarding antibody evasion but may be more transmissible than BA.1. The pathogenicity of BA.2 remains unclear and is of critical public health significance. Here we investigated the virological features and pathogenicity of BA.2 with in vitro and in vivo models. We show that BA.2 is less dependent on transmembrane protease serine 2 (TMPRSS2) for virus entry in comparison with BA.1 in vitro. In K18-hACE2 mice, BA.2 replicates more efficiently than BA.1 in the nasal turbinates and replicates marginally less efficiently in the lungs, leading to decreased body weight loss and improved survival. Our study indicates that BA.2 is similarly attenuated in lungs compared with BA.1 but is potentially more transmissible because of its better replication at the nasal turbinates.


Asunto(s)
COVID-19 , SARS-CoV-2 , Animales , Humanos , Ratones , SARS-CoV-2/genética , Serina , Virulencia
10.
Emerg Microbes Infect ; 11(1): 2275-2287, 2022 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-36039901

RESUMEN

SARS-CoV-2 B.1.1.529.1 (Omicron BA.1) emerged in November 2021 and quickly became the predominant circulating SARS-CoV-2 variant globally. Omicron BA.1 contains more than 30 mutations in the spike protein, which contribute to its altered virological features when compared to the ancestral SARS-CoV-2 or previous SARS-CoV-2 variants. Recent studies by us and others demonstrated that Omicron BA.1 is less dependent on transmembrane serine protease 2 (TMPRSS2), less efficient in spike cleavage, less fusogenic, and adopts an altered propensity to utilize the plasma membrane and endosomal pathways for virus entry. Ongoing studies suggest that these virological features of Omicron BA.1 are in part retained by the subsequent Omicron sublineages. However, the exact spike determinants that contribute to these altered features of Omicron remain incompletely understood. In this study, we investigated the spike determinants for the observed virological characteristics of Omicron. By screening for the individual changes on Omicron BA.1 and BA.2 spike, we identify that 69-70 deletion, E484A, and H655Y contribute to the reduced TMPRSS2 usage while 25-27 deletion, S375F, and T376A result in less efficient spike cleavage. Among the shared spike mutations of BA.1 and BA.2, S375F and H655Y reduce spike-mediated fusogenicity. Interestingly, the H655Y change consistently reduces serine protease usage while increases the use of endosomal proteases. In keeping with these findings, the H655Y substitution alone reduces plasma membrane entry and facilitates endosomal entry when compared to SARS-CoV-2 WT. Overall, our study identifies key changes in Omicron spike that contributes to our understanding on the virological determinant and pathogenicity of Omicron.


Asunto(s)
COVID-19 , SARS-CoV-2 , Humanos , Mutación , SARS-CoV-2/genética , Glicoproteína de la Espiga del Coronavirus/genética , Glicoproteína de la Espiga del Coronavirus/metabolismo
11.
Nature ; 609(7928): 785-792, 2022 09.
Artículo en Inglés | MEDLINE | ID: mdl-35922005

RESUMEN

Highly pathogenic coronaviruses, including severe acute respiratory syndrome coronavirus 2 (refs. 1,2) (SARS-CoV-2), Middle East respiratory syndrome coronavirus3 (MERS-CoV) and SARS-CoV-1 (ref. 4), vary in their transmissibility and pathogenicity. However, infection by all three viruses results in substantial apoptosis in cell culture5-7 and in patient tissues8-10, suggesting a potential link between apoptosis and pathogenesis of coronaviruses. Here we show that caspase-6, a cysteine-aspartic protease of the apoptosis cascade, serves as an important host factor for efficient coronavirus replication. We demonstrate that caspase-6 cleaves coronavirus nucleocapsid proteins, generating fragments that serve as interferon antagonists, thus facilitating virus replication. Inhibition of caspase-6 substantially attenuates lung pathology and body weight loss in golden Syrian hamsters infected with SARS-CoV-2 and improves the survival of mice expressing human DPP4 that are infected with mouse-adapted MERS-CoV. Our study reveals how coronaviruses exploit a component of the host apoptosis cascade to facilitate virus replication.


Asunto(s)
Ácido Aspártico , Caspasa 6 , Infecciones por Coronavirus , Coronavirus , Cisteína , Interacciones Huésped-Patógeno , Replicación Viral , Animales , Apoptosis , Ácido Aspártico/metabolismo , Caspasa 6/metabolismo , Coronavirus/crecimiento & desarrollo , Coronavirus/patogenicidad , Infecciones por Coronavirus/enzimología , Infecciones por Coronavirus/virología , Proteínas de la Nucleocápside de Coronavirus/inmunología , Proteínas de la Nucleocápside de Coronavirus/metabolismo , Cricetinae , Cisteína/metabolismo , Dipeptidil Peptidasa 4/genética , Dipeptidil Peptidasa 4/metabolismo , Humanos , Interferones/antagonistas & inhibidores , Interferones/inmunología , Pulmón/patología , Mesocricetus , Ratones , Coronavirus del Síndrome Respiratorio de Oriente Medio , Coronavirus Relacionado al Síndrome Respiratorio Agudo Severo , SARS-CoV-2 , Tasa de Supervivencia , Pérdida de Peso
12.
Int J Biol Sci ; 18(12): 4714-4730, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35874959

RESUMEN

The Coronavirus Disease 2019 (COVID-19) pandemic caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is the biggest public health challenge the world has witnessed in the past decades. SARS-CoV-2 undergoes constant mutations and new variants of concerns (VOCs) with altered transmissibility, virulence, and/or susceptibility to vaccines and therapeutics continue to emerge. Detailed analysis of host factors involved in virus replication may help to identify novel treatment targets. In this study, we dissected the metabolome derived from COVID-19 patients to identify key host factors that are required for efficient SARS-CoV-2 replication. Through a series of metabolomic analyses, in vitro, and in vivo investigations, we identified ATP citrate lyase (ACLY) as a novel host factor required for efficient replication of SARS-CoV-2 wild-type and variants, including Omicron. ACLY should be further explored as a novel intervention target for COVID-19.


Asunto(s)
COVID-19 , SARS-CoV-2 , ATP Citrato (pro-S)-Liasa , Humanos , Pandemias , Replicación Viral/genética
13.
JCI Insight ; 7(11)2022 06 08.
Artículo en Inglés | MEDLINE | ID: mdl-35446790

RESUMEN

SARS-CoV-2 has been confirmed in over 450 million confirmed cases since 2019. Although several vaccines have been certified by the WHO and people are being vaccinated on a global scale, it has been reported that multiple SARS-CoV-2 variants can escape neutralization by antibodies, resulting in vaccine breakthrough infections. Bacillus Calmette-Guérin (BCG) is known to induce heterologous protection based on trained immune responses. Here, we investigated whether BCG-induced trained immunity protected against SARS-CoV-2 in the K18-hACE2 mouse model. Our data demonstrate that i.v. BCG (BCG-i.v.) vaccination induces robust trained innate immune responses and provides protection against WT SARS-CoV-2, as well as the B.1.617.1 and B.1.617.2 variants. Further studies suggest that myeloid cell differentiation and activation of the glycolysis pathway are associated with BCG-induced training immunity in K18-hACE2 mice. Overall, our study provides the experimental evidence that establishes a causal relationship between BCG-i.v. vaccination and protection against SARS-CoV-2 challenge.


Asunto(s)
COVID-19 , SARS-CoV-2 , Animales , Vacuna BCG , COVID-19/prevención & control , Humanos , Melfalán , Ratones , gammaglobulinas
14.
Front Public Health ; 10: 825645, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35284384

RESUMEN

Influenza-like illness (ILI) is one of the most important public health problems globally, causing an enormous disease burden. Influenza infections are the most common cause of ILI. Bacterial and virus co-infection is common yet the data of co-infection with influenza A and B viruses are scarce. To identify the epidemiological patterns of and co-infection of influenza A and B in Anhui province, China, we analyzed the surveillance data of 5 years from 2009 to 2014 collected by the Chinese National influenzas network. The results showed that the weekly ratio of ILI was 3.96 ± 1.9% (95% CI 3.73-4.2%) in outpatients and the highest affected population was children under 5 years old. The epidemic of influenza viruses was highest during 2009-2010. For the other 4 surveillance years, school-aged people (5-14 years) were the most highly affected population. Influenza B and H3N2 viruses were more prevalent than H1N1pdm09 virus after 2010. In addition, a significant co-circulation of influenza A (H1N1pdm09 and H3N2) and influenza B virus was detected with 0.057% PCR positive rate during 2009-2014 in Eastern China, yet isolated only in pediatric patients. Our data reveals school-aged population would be the main vulnerable population and a distinct seasonality for influenza. In addition, the co-infection of influenza A and B were found in Anhui Province, China. Ongoing surveillance is critical to understand the seasonality variation and make evidence-based vaccination recommendations. Information on the epidemiological patterns and co-infections of influenza A and B can help us to implement different strategies for selecting vaccine formulations and monitoring new emerging influenza strains. In addition, the identification of the susceptible population can help us to develop more precise protection measures.


Asunto(s)
Coinfección , Vacunas contra la Influenza , Gripe Humana , Niño , Preescolar , China/epidemiología , Coinfección/epidemiología , Humanos , Subtipo H3N2 del Virus de la Influenza A , Virus de la Influenza B , Gripe Humana/epidemiología
15.
Nature ; 603(7902): 693-699, 2022 03.
Artículo en Inglés | MEDLINE | ID: mdl-35062016

RESUMEN

The Omicron (B.1.1.529) variant of SARS-CoV-2 emerged in November 2021 and is rapidly spreading among the human population1. Although recent reports reveal that the Omicron variant robustly escapes vaccine-associated and therapeutic neutralization antibodies2-10, the pathogenicity of the virus remains unknown. Here we show that the replication of Omicron is substantially attenuated in human Calu3 and Caco2 cells. Further mechanistic investigations reveal that Omicron is inefficient in its use of transmembrane serine protease 2 (TMPRSS2) compared with wild-type SARS-CoV-2 (HKU-001a) and previous variants, which may explain its reduced replication in Calu3 and Caco2 cells. The replication of Omicron is markedly attenuated in both the upper and lower respiratory tracts of infected K18-hACE2 mice compared with that of the wild-type strain and Delta (B.1.617.2) variant, resulting in its substantially ameliorated lung pathology. Compared with wild-type SARS-CoV-2 and the Alpha (B.1.1.7), Beta (1.351) and Delta variants, infection by Omicron causes the lowest reduction in body weight and the lowest mortality rate. Overall, our study demonstrates that the replication and pathogenicity of the Omicron variant of SARS-CoV-2 in mice is attenuated compared with the wild-type strain and other variants.


Asunto(s)
COVID-19/patología , COVID-19/virología , SARS-CoV-2/patogenicidad , Replicación Viral , Enzima Convertidora de Angiotensina 2/genética , Enzima Convertidora de Angiotensina 2/metabolismo , Animales , COVID-19/inmunología , Células CACO-2 , Femenino , Humanos , Masculino , Ratones , Ratones Endogámicos C57BL , Ratones Transgénicos , SARS-CoV-2/inmunología , SARS-CoV-2/metabolismo , Serina Endopeptidasas/metabolismo , Virulencia
16.
Clin Infect Dis ; 75(1): e1101-e1111, 2022 08 24.
Artículo en Inglés | MEDLINE | ID: mdl-34536277

RESUMEN

BACKGROUND: The effect of low environmental temperature on viral shedding and disease severity of Coronavirus Disease 2019 (COVID-19) is uncertain. METHODS: We investigated the virological, clinical, pathological, and immunological changes in hamsters housed at room (21°C), low (12-15°C), and high (30-33°C) temperature after challenge by 105 plaque-forming units of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). RESULTS: The nasal turbinate, trachea, and lung viral load and live virus titer were significantly higher (~0.5-log10 gene copies/ß-actin, P < .05) in the low-temperature group at 7 days postinfection (dpi). The low-temperature group also demonstrated significantly higher level of tumor necrosis factor-α, interferon-γ (IFN-γ), interleukin-1ß, and C-C motif chemokine ligand 3, and lower level of the antiviral IFN-α in lung tissues at 4 dpi than the other 2 groups. Their lungs were grossly and diffusely hemorrhagic, with more severe and diffuse alveolar and peribronchiolar inflammatory infiltration, bronchial epithelial cell death, and significantly higher mean total lung histology scores. By 7 dpi, the low-temperature group still showed persistent and severe alveolar inflammation and hemorrhage, and little alveolar cell proliferative changes of recovery. The viral loads in the oral swabs of the low-temperature group were significantly higher than those of the other two groups from 10 to 17 dpi by about 0.5-1.0 log10 gene copies/ß-actin. The mean neutralizing antibody titer of the low-temperature group was significantly (P < .05) lower than that of the room temperature group at 7 dpi and 30 dpi. CONCLUSIONS: This study provided in vivo evidence that low environmental temperature exacerbated the degree of virus shedding, disease severity, and tissue proinflammatory cytokines/chemokines expression, and suppressed the neutralizing antibody response of SARS-CoV-2-infected hamsters. Keeping warm in winter may reduce the severity of COVID-19.


Asunto(s)
COVID-19 , Actinas , Animales , Anticuerpos Neutralizantes , Cricetinae , Modelos Animales de Enfermedad , Humanos , Pulmón , Mesocricetus , SARS-CoV-2 , Temperatura
17.
EBioMedicine ; 73: 103643, 2021 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-34689086

RESUMEN

BACKGROUND: Wildtype mice are not susceptible to SARS-CoV-2 infection. Emerging SARS-CoV-2 variants, including B.1.1.7, B.1.351, P.1, and P.3, contain mutations in spike that has been suggested to associate with an increased recognition of mouse ACE2, raising the postulation that these SARS-CoV-2 variants may have evolved to expand species tropism to wildtype mouse and potentially other murines. Our study evaluated this possibility with substantial public health importance. METHODS: We investigated the capacity of wildtype (WT) SARS-CoV-2 and SARS-CoV-2 variants in infecting mice (Mus musculus) and rats (Rattus norvegicus) under in vitro and in vivo settings. Susceptibility to infection was evaluated with RT-qPCR, plaque assays, immunohistological stainings, and neutralization assays. FINDINGS: Our results reveal that B.1.1.7 and other N501Y-carrying variants but not WT SARS-CoV-2 can infect wildtype mice. High viral genome copies and high infectious virus particle titres are recovered from the nasal turbinate and lung of B.1.1.7-inocluated mice for 4-to-7 days post infection. In agreement with these observations, robust expression of viral nucleocapsid protein and histopathological changes are detected from the nasal turbinate and lung of B.1.1.7-inocluated mice but not that of the WT SARS-CoV-2-inoculated mice. Similarly, B.1.1.7 readily infects wildtype rats with production of infectious virus particles. INTERPRETATION: Our study provides direct evidence that the SARS-CoV-2 variant, B.1.1.7, as well as other N501Y-carrying variants including B.1.351 and P.3, has gained the capability to expand species tropism to murines and public health measures including stringent murine control should be implemented to facilitate the control of the ongoing pandemic. FUNDING: A full list of funding bodies that contributed to this study can be found in the Acknowledgements section.


Asunto(s)
COVID-19/patología , SARS-CoV-2/fisiología , Tropismo Viral , Enzima Convertidora de Angiotensina 2/genética , Enzima Convertidora de Angiotensina 2/metabolismo , Animales , Anticuerpos Antivirales/sangre , Anticuerpos Antivirales/inmunología , COVID-19/virología , Femenino , Humanos , Pulmón/patología , Pulmón/virología , Ratones , Ratones Endogámicos C57BL , Ratones Transgénicos , Pruebas de Neutralización , Proteínas de la Nucleocápside/inmunología , Proteínas de la Nucleocápside/metabolismo , ARN Viral/análisis , ARN Viral/metabolismo , Ratas , Ratas Sprague-Dawley , SARS-CoV-2/inmunología , SARS-CoV-2/aislamiento & purificación , Cornetes Nasales/patología , Cornetes Nasales/virología , Internalización del Virus
18.
J Med Virol ; 93(10): 5998-6007, 2021 10.
Artículo en Inglés | MEDLINE | ID: mdl-34232513

RESUMEN

In the context of the coronavirus disease 2019 pandemic, we investigated the epidemiological and clinical characteristics of a young patient infected by avian influenza A (H5N6) virus in Anhui Province, East China, and analyzed genomic features of the pathogen in 2020. Through the cross-sectional investigation of external environment monitoring (December 29-31, 2020), 1909 samples were collected from Fuyang City. It was found that the positive rate of H5N6 was higher than other areas obviously in Tianma poultry market, where the case appeared. In addition, dual coinfections were detected with a 0.057% polymerase chain reaction positive rate the surveillance years. The virus was the clade 2.3.4.4, which was most likely formed by genetic reassortment between H5N6 and H9N2 viruses. This study found that the evolution rates of the hemagglutinin and neuraminidase genes of the virus were higher than those of common seasonal influenza viruses. The virus was still highly pathogenic to poultry and had a preference for avian receptor binding.


Asunto(s)
COVID-19/epidemiología , Virus de la Influenza A/aislamiento & purificación , Gripe Aviar/virología , Gripe Humana/virología , Animales , Preescolar , China , Femenino , Genoma Viral/genética , Humanos , Virus de la Influenza A/clasificación , Virus de la Influenza A/genética , Gripe Humana/diagnóstico , Mutación , Filogenia , Aves de Corral/virología , Virus Reordenados/clasificación , Virus Reordenados/genética , Virus Reordenados/aislamiento & purificación , SARS-CoV-2 , Proteínas Virales/genética
19.
Sci Adv ; 7(25)2021 06.
Artículo en Inglés | MEDLINE | ID: mdl-34134991

RESUMEN

Infection by highly pathogenic coronaviruses results in substantial apoptosis. However, the physiological relevance of apoptosis in the pathogenesis of coronavirus infections is unknown. Here, with a combination of in vitro, ex vivo, and in vivo models, we demonstrated that protein kinase R-like endoplasmic reticulum kinase (PERK) signaling mediated the proapoptotic signals in Middle East respiratory syndrome coronavirus (MERS-CoV) infection, which converged in the intrinsic apoptosis pathway. Inhibiting PERK signaling or intrinsic apoptosis both alleviated MERS pathogenesis in vivo. Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) and SARS-CoV induced apoptosis through distinct mechanisms but inhibition of intrinsic apoptosis similarly limited SARS-CoV-2- and SARS-CoV-induced apoptosis in vitro and markedly ameliorated the lung damage of SARS-CoV-2-inoculated human angiotensin-converting enzyme 2 (hACE2) mice. Collectively, our study provides the first evidence that virus-induced apoptosis is an important disease determinant of highly pathogenic coronaviruses and demonstrates that this process can be targeted to attenuate disease severity.


Asunto(s)
Antivirales/farmacología , Apoptosis/efectos de los fármacos , Tratamiento Farmacológico de COVID-19 , Infecciones por Coronavirus/tratamiento farmacológico , eIF-2 Quinasa/metabolismo , Adenina/análogos & derivados , Adenina/farmacología , Enzima Convertidora de Angiotensina 2/genética , Animales , Apoptosis/fisiología , COVID-19/etiología , COVID-19/patología , Línea Celular , Infecciones por Coronavirus/etiología , Infecciones por Coronavirus/patología , Dipeptidil Peptidasa 4/genética , Células Epiteliales/virología , Femenino , Humanos , Indoles/farmacología , Pulmón/virología , Masculino , Ratones Transgénicos , eIF-2 Quinasa/antagonistas & inhibidores , eIF-2 Quinasa/genética
20.
Emerg Microbes Infect ; 10(1): 1024-1037, 2021 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-33979266

RESUMEN

Zika virus (ZIKV) is an emerging mosquito-borne flavivirus that poses significant threats to global public health. Macrophages and dendritic cells are both key sentinel cells in the host immune response and play critical roles in the pathogenesis of flavivirus infections. Recent studies showed that ZIKV could productively infect monocyte-derived dendritic cells (moDCs), but the role of macrophages in ZIKV infection remains incompletely understood. In this study, we first compared ZIKV infection in monocyte-derived macrophages (MDMs) and moDCs derived from the same donors. We demonstrated that while both MDMs and moDCs were susceptible to epidemic (Puerto Rico) and pre-epidemic (Uganda) strains of ZIKV, virus replication was largely restricted in MDMs but not in moDCs. ZIKV induced significant apoptosis in moDCs but not MDMs. The restricted virus replication in MDMs was not due to inefficient virus entry but was related to post-entry events in the viral replication cycle. In stark contrast with moDCs, ZIKV failed to inhibit STAT1 and STAT2 phosphorylation in MDMs. This resulted in the lack of efficient antagonism of the host type I interferon-mediated antiviral responses. Importantly, depletion of STAT2 but not STAT1 in MDMs significantly rescued the replication of ZIKV and the prototype flavivirus yellow fever virus. Overall, our findings revealed a differential interplay between macrophages and dendritic cells with ZIKV. While dendritic cells may be exploited by ZIKV to facilitate virus replication, macrophages restricted ZIKV infection.


Asunto(s)
Células Dendríticas/virología , Macrófagos/virología , Factor de Transcripción STAT1/metabolismo , Factor de Transcripción STAT2/metabolismo , Virus Zika/fisiología , Animales , Línea Celular , Chlorocebus aethiops , Células Dendríticas/efectos de los fármacos , Células Dendríticas/metabolismo , Técnicas de Inactivación de Genes , Humanos , Interferón Tipo I/farmacología , Macrófagos/efectos de los fármacos , Macrófagos/metabolismo , Fosforilación , Factor de Transcripción STAT1/genética , Factor de Transcripción STAT2/genética , Células Vero , Replicación Viral , Infección por el Virus Zika/metabolismo
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