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1.
Nat Commun ; 15(1): 2887, 2024 Apr 04.
Artículo en Inglés | MEDLINE | ID: mdl-38575573

RESUMEN

Anthropogenic disturbances and the subsequent loss of biodiversity are altering species abundances and communities. Since species vary in their pathogen competence, spatio-temporal changes in host assemblages may lead to changes in disease dynamics. We explore how longitudinal changes in bat species assemblages affect the disease dynamics of coronaviruses (CoVs) in more than 2300 cave-dwelling bats captured over two years from five caves in Ghana. This reveals uneven CoV infection patterns between closely related species, with the alpha-CoV 229E-like and SARS-related beta-CoV 2b emerging as multi-host pathogens. Prevalence and infection likelihood for both phylogenetically distinct CoVs is influenced by the abundance of competent species and naïve subadults. Broadly, bat species vary in CoV competence, and highly competent species are more common in less diverse communities, leading to increased CoV prevalence in less diverse bat assemblages. In line with the One Health framework, our work supports the notion that biodiversity conservation may be the most proactive measure to prevent the spread of pathogens with zoonotic potential.


Asunto(s)
Quirópteros , Infecciones por Coronavirus , Coronavirus , Coronavirus Relacionado al Síndrome Respiratorio Agudo Severo , Animales , Coronavirus/genética , Prevalencia , Filogenia , Infecciones por Coronavirus/epidemiología
2.
Viruses ; 16(3)2024 Mar 21.
Artículo en Inglés | MEDLINE | ID: mdl-38543849

RESUMEN

Severe acute respiratory syndrome (SARS)-coronavirus (CoV), Middle Eastern respiratory syndrome (MERS)-CoV, and SARS-CoV-2 have seriously threatened human life in the 21st century. Emerging and re-emerging ß-coronaviruses after the coronavirus disease 2019 (COVID-19) epidemic remain possible highly pathogenic agents that can endanger human health. Thus, pan-ß-coronavirus vaccine strategies to combat the upcoming dangers are urgently needed. In this study, four LNP-mRNA vaccines, named O, D, S, and M, targeting the spike protein of SARS-CoV-2 Omicron, Delta, SARS-CoV, and MERS-CoV, respectively, were synthesized and characterized for purity and integrity. All four LNP-mRNAs induced effective cellular and humoral immune responses against the corresponding spike protein antigens in mice. Furthermore, LNP-mRNA S and D induced neutralizing antibodies against SARS-CoV and SARS-CoV-2, which failed to cross-react with MERS-CoV. Subsequent evaluation of sequential and cocktail immunizations with LNP-mRNA O, D, S, and M effectively elicited broad immunity against SARS-CoV-2 variants, SARS-CoV, and MERS-CoV. A direct comparison of the sequential with cocktail regimens indicated that the cocktail vaccination strategy induced more potent neutralizing antibodies and T-cell responses against heterotypic viruses as well as broader antibody activity against pan-ß-coronaviruses. Overall, these results present a potential pan-ß-coronavirus vaccine strategy for improved preparedness prior to future coronavirus threats.


Asunto(s)
Liposomas , Nanopartículas , Coronavirus Relacionado al Síndrome Respiratorio Agudo Severo , Vacunas Virales , Animales , Ratones , Humanos , Vacunas de ARNm , SARS-CoV-2/genética , Vacunas contra la COVID-19 , Glicoproteína de la Espiga del Coronavirus/genética , Modelos Animales de Enfermedad , Vacunas Virales/genética , Coronavirus Relacionado al Síndrome Respiratorio Agudo Severo/genética , Anticuerpos Neutralizantes , ARN Mensajero/genética , Inmunidad , Anticuerpos Antivirales
4.
J Appl Genet ; 65(2): 403-413, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38514586

RESUMEN

tsRNAs (tRNA-derived small non-coding RNAs), including tRNA halves (tiRNAs) and tRNA fragments (tRFs), have been implicated in some viral infections, such as respiratory viral infections. However, their involvement in SARS-CoV infection is completely unknown. A comprehensive analysis was performed to determine tsRNA populations in a mouse model of SARS-CoV-infected samples containing the wild-type and attenuated viruses. Data from the Gene Expression Omnibus (GEO) dataset at NCBI (accession ID GSE90624 ) was used for this study. A count matrix was generated for the tRNAs. Differentially expressed tRNAs, followed by tsRNAs derived from each significant tRNAs at different conditions and time points between the two groups WT(SARS-CoV-MA15-WT) vs Mock and ΔE (SARS-CoV-MA15-ΔE) vs Mock were identified. Notably, significantly differentially expressed tRNAs at 2dpi but not at 4dpi. The tsRNAs originating from differentially expressed tRNAs across all the samples belonging to each condition (WT, ΔE, and Mock) were identified. Intriguingly, tRFs (tRNA-derived RNA fragments) exhibited higher levels compared to tiRNAs (tRNA-derived stress-induced RNAs) across all samples associated with WT SARS-CoV strain compared to ΔE and mock-infected samples. This discrepancy suggests a non-random formation of tsRNAs, hinting at a possible involvement of tsRNAs in SARS-CoV viral infection.


Asunto(s)
Coronavirus Relacionado al Síndrome Respiratorio Agudo Severo , Virosis , Ratones , Animales , ARN de Transferencia/genética , ARN de Transferencia/metabolismo , Coronavirus Relacionado al Síndrome Respiratorio Agudo Severo/genética
5.
Viruses ; 16(2)2024 Jan 31.
Artículo en Inglés | MEDLINE | ID: mdl-38399999

RESUMEN

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), the novel coronavirus responsible for the coronavirus disease 2019 (COVID-19) pandemic, represents a serious threat to public health. The spike (S) glycoprotein of SARS-CoV-2 mediates viral entry into host cells and is heavily glycosylated. In this study, we systemically analyzed the roles of 22 putative N-linked glycans in SARS-CoV-2 S protein expression, membrane fusion, viral entry, and stability. Using the α-glycosidase inhibitors castanospermine and NB-DNJ, we confirmed that disruption of N-linked glycosylation blocked the maturation of the S protein, leading to the impairment of S protein-mediated membrane fusion. Single-amino-acid substitution of each of the 22 N-linked glycosylation sites with glutamine revealed that 9 out of the 22 N-linked glycosylation sites were critical for S protein folding and maturation. Thus, substitution at these sites resulted in reduced S protein-mediated cell-cell fusion and viral entry. Notably, the N1074Q mutation markedly affected S protein stability and induced significant receptor-independent syncytium (RIS) formation in HEK293T/hACE2-KO cells. Additionally, the removal of the furin cleavage site partially compensated for the instability induced by the N1074Q mutation. Although the corresponding mutation in the SARS-CoV S protein (N1056Q) did not induce RIS in HEK293T cells, the N669Q and N1080Q mutants exhibited increased fusogenic activity and did induce syncytium formation in HEK293T cells. Therefore, N-glycans on the SARS-CoV and SARS-CoV-2 S2 subunits are highly important for maintaining the pre-fusion state of the S protein. This study revealed the critical roles of N-glycans in S protein maturation and stability, information that has implications for the design of vaccines and antiviral strategies.


Asunto(s)
COVID-19 , Coronavirus Relacionado al Síndrome Respiratorio Agudo Severo , Humanos , SARS-CoV-2/genética , SARS-CoV-2/metabolismo , Glicoproteína de la Espiga del Coronavirus/metabolismo , Glicosilación , Células HEK293 , Polisacáridos/metabolismo , Internalización del Virus
6.
Nat Commun ; 15(1): 1284, 2024 Feb 12.
Artículo en Inglés | MEDLINE | ID: mdl-38346966

RESUMEN

The 2002 SARS outbreak, the 2019 emergence of COVID-19, and the continuing evolution of immune-evading SARS-CoV-2 variants together highlight the need for a broadly protective vaccine against ACE2-utilizing sarbecoviruses. While updated variant-matched formulations are a step in the right direction, protection needs to extend beyond SARS-CoV-2 and its variants to include SARS-like viruses. Here, we introduce bivalent and trivalent vaccine formulations using our spike protein nanoparticle platform that completely protect female hamsters against BA.5 and XBB.1 challenges with no detectable virus in the lungs. The trivalent cocktails elicit highly neutralizing responses against all tested Omicron variants and the bat sarbecoviruses SHC014 and WIV1. Finally, our 614D/SHC014/XBB trivalent spike formulation completely protects human ACE2-transgenic female hamsters against challenges with WIV1 and SHC014 with no detectable virus in the lungs. Collectively, these results illustrate that our trivalent protein-nanoparticle cocktail can provide broad protection against SARS-CoV-2-like and SARS-CoV-1-like sarbecoviruses.


Asunto(s)
Nanovacunas , Coronavirus Relacionado al Síndrome Respiratorio Agudo Severo , Animales , Cricetinae , Humanos , Femenino , Enzima Convertidora de Angiotensina 2 , Vacunación , Inmunización , Anticuerpos Neutralizantes , Anticuerpos Antivirales
7.
J Neurovirol ; 30(1): 39-51, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-38172412

RESUMEN

Sarbecoviruses such as SARS and SARS-CoV-2 have been responsible for two major outbreaks in humans, the latter resulting in a global pandemic. While sarbecoviruses primarily cause an acute respiratory infection, they have been shown to infect the nervous system. However, mechanisms of sarbecovirus neuroinvasion and neuropathogenesis remain unclear. In this study, we examined the infectivity and trans-synaptic transmission potential of the sarbecoviruses SARS and SARS-CoV-2 in human stem cell-derived neural model systems. We demonstrated limited ability of sarbecoviruses to infect and replicate in human stem cell-derived neurons. Furthermore, we demonstrated an inability of sarbecoviruses to transmit between synaptically connected human stem cell-derived neurons. Finally, we determined an absence of SARS-CoV-2 infection in olfactory neurons in experimentally infected ferrets. Collectively, this study indicates that sarbecoviruses exhibit low potential to infect human stem cell-derived neurons, lack an ability to infect ferret olfactory neurons, and lack an inbuilt molecular mechanism to utilise retrograde axonal trafficking and trans-synaptic transmission to spread within the human nervous system.


Asunto(s)
Axones , COVID-19 , Hurones , SARS-CoV-2 , Coronavirus Relacionado al Síndrome Respiratorio Agudo Severo , Humanos , SARS-CoV-2/patogenicidad , SARS-CoV-2/fisiología , Animales , COVID-19/virología , COVID-19/transmisión , Axones/virología , Hurones/virología , Coronavirus Relacionado al Síndrome Respiratorio Agudo Severo/fisiología , Coronavirus Relacionado al Síndrome Respiratorio Agudo Severo/patogenicidad , Neuronas/virología , Replicación Viral , Chlorocebus aethiops , Células-Madre Neurales/virología , Células Vero
8.
Nat Commun ; 15(1): 200, 2024 Jan 03.
Artículo en Inglés | MEDLINE | ID: mdl-38172512

RESUMEN

The repeat emergence of SARS-CoV-2 variants of concern (VoC) with decreased susceptibility to vaccine-elicited antibodies highlights the need to develop next-generation vaccine candidates that confer broad protection. Here we describe the antibody response induced by the SARS-CoV-2 Spike Ferritin Nanoparticle (SpFN) vaccine candidate adjuvanted with the Army Liposomal Formulation including QS21 (ALFQ) in non-human primates. By isolating and characterizing several monoclonal antibodies directed against the Spike Receptor Binding Domain (RBD), N-Terminal Domain (NTD), or the S2 Domain, we define the molecular recognition of vaccine-elicited cross-reactive monoclonal antibodies (mAbs) elicited by SpFN. We identify six neutralizing antibodies with broad sarbecovirus cross-reactivity that recapitulate serum polyclonal antibody responses. In particular, RBD mAb WRAIR-5001 binds to the conserved cryptic region with high affinity to sarbecovirus clades 1 and 2, including Omicron variants, while mAb WRAIR-5021 offers complete protection from B.1.617.2 (Delta) in a murine challenge study. Our data further highlight the ability of SpFN vaccination to stimulate cross-reactive B cells targeting conserved regions of the Spike with activity against SARS CoV-1 and SARS-CoV-2 variants.


Asunto(s)
Nanopartículas , Coronavirus Relacionado al Síndrome Respiratorio Agudo Severo , Animales , Ratones , Anticuerpos Neutralizantes , Macaca mulatta , Vacunación , Anticuerpos Antivirales , Anticuerpos Monoclonales , Vacunas contra la COVID-19 , Ferritinas , Glicoproteína de la Espiga del Coronavirus/genética
9.
ACS Infect Dis ; 10(2): 553-561, 2024 Feb 09.
Artículo en Inglés | MEDLINE | ID: mdl-38281136

RESUMEN

Structure-guided rational immunogen design can generate optimized immunogens that elicit a desired humoral response. Design strategies often center on targeting conserved sites on viral glycoproteins that will ultimately confer potent neutralization. For SARS-CoV-2 (SARS-2), the surface-exposed spike glycoprotein includes a broadly conserved portion, the receptor binding motif (RBM), that is required to engage the host cellular receptor, ACE2. Expanding humoral responses to this site may result in a more potent neutralizing antibody response against diverse sarbecoviruses. Here, we used a "resurfacing" approach and iterative design cycles to graft the SARS-2 RBM onto heterologous sarbecovirus scaffolds. The scaffolds were selected to vary the antigenic distance relative to SARS-2 to potentially focus responses to RBM. Multimerized versions of these immunogens elicited broad neutralization against sarbecoviruses in the context of preexisting SARS-2 immunity. These validated engineering approaches can help inform future immunogen design efforts for sarbecoviruses and are generally applicable to other viruses.


Asunto(s)
COVID-19 , Coronavirus Relacionado al Síndrome Respiratorio Agudo Severo , Humanos , SARS-CoV-2 , Anticuerpos Neutralizantes
10.
ACS Infect Dis ; 10(2): 398-411, 2024 Feb 09.
Artículo en Inglés | MEDLINE | ID: mdl-38270149

RESUMEN

The SARS-CoV-1 spike glycoprotein contains a fusion peptide (FP) segment that mediates the fusion of the viral and host cell membranes. Calcium ions are thought to position the FP optimally for membrane insertion by interacting with negatively charged residues in this segment (E801, D802, D812, E821, D825, and D830); however, which residues bind to calcium and in what combinations supportive of membrane insertion are unknown. Using biological assays and molecular dynamics studies, we have determined the functional configurations of FP-Ca2+ binding that likely promote membrane insertion. We first individually mutated the negatively charged residues in the SARS CoV-1 FP to assay their roles in cell entry and syncytia formation, finding that charge loss in the D802A or D830A mutants greatly reduced syncytia formation and pseudoparticle transduction of VeroE6 cells. Interestingly, one mutation (D812A) led to a modest increase in cell transduction, further indicating that FP function likely depends on calcium binding at specific residues and in specific combinations. To interpret these results mechanistically and identify specific modes of FP-Ca2+ binding that modulate membrane insertion, we performed molecular dynamics simulations of the SARS-CoV-1 FP and Ca2+ions. The preferred residue pairs for Ca2+ binding we identified (E801/D802, E801/D830, and D812/E821) include the two residues found to be essential for S function in our biological studies (D802 and D830). The three preferred Ca2+ binding pairs were also predicted to promote FP membrane insertion. We also identified a Ca2+ binding pair (E821/D825) predicted to inhibit FP membrane insertion. We then carried out simulations in the presence of membranes and found that binding of Ca2+ to SARS-CoV-1 FP residue pairs E801/D802 and D812/E821 facilitates membrane insertion by enabling the peptide to adopt conformations that shield the negative charges of the FP to reduce repulsion by the membrane phospholipid headgroups. This calcium binding mode also optimally positions the hydrophobic LLF region of the FP for membrane penetration. Conversely, Ca2+ binding to the FP E801/D802 and D821/D825 pairs eliminates the negative charge screening and instead creates a repulsive negative charge that hinders membrane penetration of the LLF motif. These computational results, taken together with our biological studies, provide an improved and nuanced mechanistic understanding of the dymanics of SARS-CoV-1 calcium binding and their potential effects on host cell entry.


Asunto(s)
Coronavirus Relacionado al Síndrome Respiratorio Agudo Severo , Secuencia de Aminoácidos , Calcio/metabolismo , Fusión de Membrana/fisiología , Péptidos/química , Iones
11.
Cell Rep ; 43(1): 113653, 2024 01 23.
Artículo en Inglés | MEDLINE | ID: mdl-38175758

RESUMEN

Omicron, as the emerging variant with enhanced vaccine tolerance, has sharply disrupted most therapeutic antibodies. Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) belongs to the subgenus Sarbecovirus, members of which share high sequence similarity. Herein, we report one sarbecovirus antibody, 5817, which has broad-spectrum neutralization capacity against SARS-CoV-2 variants of concern (VOCs) and SARS-CoV, as well as related bat and pangolin viruses. 5817 can hardly compete with six classes of receptor-binding-domain-targeted antibodies grouped by structural classifications. No obvious impairment in the potency is detected against SARS-CoV-2 Omicron and subvariants. The cryoelectron microscopy (cryo-EM) structure of neutralizing antibody 5817 in complex with Omicron spike reveals a highly conserved epitope, only existing at the receptor-binding domain (RBD) open state. Prophylactic and therapeutic administration of 5817 potently protects mice from SARS-CoV-2 Beta, Delta, Omicron, and SARS-CoV infection. This study reveals a highly conserved cryptic epitope targeted by a broad sarbecovirus neutralizing antibody, which would be beneficial to meet the potential threat of pre-emergent SARS-CoV-2 VOCs.


Asunto(s)
Coronavirus Relacionado al Síndrome Respiratorio Agudo Severo , Animales , Ratones , Anticuerpos ampliamente neutralizantes , Microscopía por Crioelectrón , Anticuerpos Neutralizantes , Epítopos , Anticuerpos Antivirales
12.
Planta Med ; 90(3): 172-203, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-37956978

RESUMEN

In early 2020, a global pandemic was announced due to the emergence of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), known to cause COVID-19. Despite worldwide efforts, there are only limited options regarding antiviral drug treatments for COVID-19. Although vaccines are now available, issues such as declining efficacy against different SARS-CoV-2 variants and the aging of vaccine-induced immunity highlight the importance of finding more antiviral drugs as a second line of defense against the disease. Drug repurposing has been used to rapidly find COVID-19 therapeutic options. Due to the lack of clinical evidence for the therapeutic benefits and certain serious side effects of repurposed antivirals, the search for an antiviral drug against SARS-CoV-2 with fewer side effects continues. In recent years, numerous studies have included antiviral chemicals from a variety of plant species. A better knowledge of the possible antiviral natural products and their mechanism against SARS-CoV-2 will help to develop stronger and more targeted direct-acting antiviral agents. The aim of the present study was to compile the current data on potential plant metabolites that can be investigated in COVID-19 drug discovery and development. This review represents a collection of plant secondary metabolites and their mode of action against SARS-CoV and SARS-CoV-2.


Asunto(s)
COVID-19 , Hepatitis C Crónica , Coronavirus Relacionado al Síndrome Respiratorio Agudo Severo , Humanos , SARS-CoV-2 , Antivirales/farmacología , Antivirales/uso terapéutico , Tratamiento Farmacológico de COVID-19 , Hepatitis C Crónica/tratamiento farmacológico , Descubrimiento de Drogas
13.
Annu Rev Pathol ; 19: 423-451, 2024 Jan 24.
Artículo en Inglés | MEDLINE | ID: mdl-37832946

RESUMEN

Over the last two decades the world has witnessed the global spread of two genetically related highly pathogenic coronaviruses, severe acute respiratory syndrome coronavirus (SARS-CoV) and SARS-CoV-2. However, the impact of these outbreaks differed significantly with respect to the hospitalizations and fatalities seen worldwide. While many studies have been performed recently on SARS-CoV-2, a comparative pathogenesis analysis with SARS-CoV may further provide critical insights into the mechanisms of disease that drive coronavirus-induced respiratory disease. In this review, we comprehensively describe clinical and experimental observations related to transmission and pathogenesis of SARS-CoV-2 in comparison with SARS-CoV, focusing on human, animal, and in vitro studies. By deciphering the similarities and disparities of SARS-CoV and SARS-CoV-2, in terms of transmission and pathogenesis mechanisms, we offer insights into the divergent characteristics of these two viruses. This information may also be relevant to assessing potential novel introductions of genetically related highly pathogenic coronaviruses.


Asunto(s)
COVID-19 , Coronavirus Relacionado al Síndrome Respiratorio Agudo Severo , Animales , Humanos , SARS-CoV-2
14.
Virus Res ; 340: 199300, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-38092254

RESUMEN

ACE2 has been confirmed to be a functional receptor for SARS-CoV and SARS-CoV-2, but research on animal coronaviruses, especially PEDV, are still unknown. The present study investigated whether ACE2 plays a role in receptor recognition and subsequent infection during PEDV invasion of host cells. IPEC-J2 cells stably expressing porcine ACE2 did not increase the production of PEDV-N but inhibited its expression. Porcine ACE2 knockout cells was generated by CRISPR/Cas9 genome editing in IPEC-J2 cells. The expression of PEDV-N did not decrease but slightly increased. The Co-IP results showed that there was no significant association between ACE2 and PEDV-S. There were no obvious interaction between PEDV-S, PEDV-E, PEDV-M and porcine ACE2 promoters, but PEDV-N could inhibit the activity of ACE2 promoters. PEDV-N degraded STAT1 and prevented its phosphorylation, thereby inhibiting the expression of interferon-stimulated genes. Repeated infection of PEDV further confirmed the above results. PEDV activated ACE-Ang II-AT1R axis, while ACE2-Ang (1-7)-MasR axis activity was decreased and inflammatory response was intensified. However, excess ACE2 can reverse this reaction. These results reveal that ACE2 does not facilitate PEDV entry into cells, but relieves PEDV-induced inflammation by promoting STAT1 phosphorylation.


Asunto(s)
Virus de la Diarrea Epidémica Porcina , Coronavirus Relacionado al Síndrome Respiratorio Agudo Severo , Chlorocebus aethiops , Porcinos , Animales , Células Vero , Línea Celular , Virus de la Diarrea Epidémica Porcina/fisiología , Enzima Convertidora de Angiotensina 2/genética , Fosforilación , SARS-CoV-2 , Células Epiteliales
15.
Pathologica ; 115(5): 257-262, 2023 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-38054900

RESUMEN

A brief overview on the management of autopsies during the SARS-CoV-19 epidemic is proposed. In particular, the point is made of the Italian laws on the subject, the characteristics required for the autopsy room and the sampling suggested for the histological examination.


Asunto(s)
Coronavirus Relacionado al Síndrome Respiratorio Agudo Severo , Humanos , Autopsia
16.
Proc Natl Acad Sci U S A ; 120(51): e2317367120, 2023 Dec 19.
Artículo en Inglés | MEDLINE | ID: mdl-38096415

RESUMEN

Vaccination will likely be a key component of strategies to curtail or prevent future sarbecovirus pandemics and to reduce the prevalence of infection and disease by future SARS-CoV-2 variants. A "pan-sarbecovirus" vaccine, that provides maximum possible mitigation of human disease, should elicit neutralizing antibodies with maximum possible breadth. By positioning multiple different receptor binding domain (RBD) antigens in close proximity on a single immunogen, it is postulated that cross-reactive B cell receptors might be selectively engaged. Heteromultimeric vaccines could therefore elicit individual antibodies that neutralize a broad range of viral species. Here, we use model systems to investigate the ability of multimeric sarbecovirus RBD immunogens to expand cross-reactive B cells and elicit broadly reactive antibodies. Homomultimeric RBD immunogens generated higher serum neutralizing antibody titers than the equivalent monomeric immunogens, while heteromultimeric RBD immunogens generated neutralizing antibodies recognizing each RBD component. Moreover, RBD heterodimers elicited a greater fraction of cross-reactive germinal center B cells and cross-reactive RBD binding antibodies than did homodimers. However, when serum antibodies from RBD heterodimer-immunized mice were depleted using one RBD component, neutralization activity against the homologous viral pseudotype was removed, but neutralization activity against pseudotypes corresponding to the other RBD component was unaffected. Overall, simply combining divergent RBDs in a single immunogen generates largely separate sets of individual RBD-specific neutralizing serum antibodies that are mostly incapable of neutralizing viruses that diverge from the immunogen components.


Asunto(s)
Anticuerpos Neutralizantes , Coronavirus Relacionado al Síndrome Respiratorio Agudo Severo , Animales , Ratones , Humanos , Anticuerpos Antivirales , Pruebas de Neutralización , Vacunación , Glicoproteína de la Espiga del Coronavirus/química
17.
Maryland; National Institutes of;Health; Dec. 20, 2023. 469 p. tab.
No convencional en Inglés | BIGG - guías GRADE | ID: biblio-1525923

RESUMEN

The COVID-19 Treatment Guidelines were developed to provide clinicians with guidance on caring for patients with COVID-19. Because clinical information about the optimal management of COVID-19 is evolving quickly, these Guidelines are updated frequently to reflect newly published data and other authoritative information.


Asunto(s)
Humanos , Masculino , Femenino , Embarazo , Recién Nacido , Lactante , Preescolar , Niño , Adolescente , Adulto , Persona de Mediana Edad , Anciano , Anciano de 80 o más Años , Coronavirus Relacionado al Síndrome Respiratorio Agudo Severo/inmunología , Prueba Serológica para COVID-19 , COVID-19/diagnóstico , Tratamiento Farmacológico de COVID-19 , Antivirales/uso terapéutico , Corticoesteroides/uso terapéutico , Suplementos Dietéticos , Inmunoterapia
18.
Monoclon Antib Immunodiagn Immunother ; 42(6): 189-193, 2023 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-38156889

RESUMEN

In small animal models of severe acute respiratory syndrome coronaviruses (SARS-CoV and SARS-CoV-2) infection, ferrets (Mustela putorius furo) have been used to investigate the pathogenesis. Podoplanin (PDPN) is an essential marker in lung type I alveolar epithelial cells, kidney podocytes, and lymphatic endothelial cells. Monoclonal antibodies (mAbs) against ferret PDPN (ferPDPN) are useful for the pathological analyses of those tissues. We previously established an anti-ferPDPN mAb, PMab-292 using the Cell-Based Immunization and Screening (CBIS) method. In this study, we determined the critical epitope of PMab-292 using flow cytometry. The ferPDPN deletion mutants analysis revealed that the Val34 is located at the N-terminus of the PMab-292 epitope. Furthermore, the PA tag-substituted analysis (PA scanning) showed that Asp39 is located at the C-terminus of PMab-292 epitope. The epitope sequence (VRPEDD) also exists between Val26 and Asp31 of ferPDPN, indicating that PMab-292 recognizes the tandem repeat of the VRPEDD sequence of ferPDPN.


Asunto(s)
Hurones , Coronavirus Relacionado al Síndrome Respiratorio Agudo Severo , Animales , Cricetinae , Mapeo Epitopo/métodos , Anticuerpos Monoclonales , Células Endoteliales , SARS-CoV-2 , Glicoproteínas de Membrana/genética , Epítopos , Células CHO , Factores de Transcripción , Cricetulus , Especificidad de Anticuerpos
19.
Viruses ; 15(12)2023 Nov 30.
Artículo en Inglés | MEDLINE | ID: mdl-38140605

RESUMEN

Coronavirus infection induces interferon-stimulated genes, one of which encodes Tetherin, a transmembrane protein inhibiting the release of various enveloped viruses from infected cells. Previous studies revealed that SARS-CoV encodes two Tetherin antagonists: the Spike protein (S), inducing lysosomal degradation of Tetherin, and ORF7a, altering its glycosylation. Similarly, SARS-CoV-2 has also been shown to use ORF7a and Spike to enhance virion release in the presence of Tetherin. Here, we directly compare the abilities and mechanisms of these two viral proteins to counteract Tetherin. Therefore, cell surface and total Tetherin levels upon ORF7a or S expression were investigated using flow cytometry and Western blot analysis. SARS-CoV and SARS-CoV-2 S only marginally reduced Tetherin cell surface levels in a cell type-dependent manner. In HEK293T cells, under conditions of high exogenous Tetherin expression, SARS-CoV-2 S and ORF7a reduced total cellular Tetherin levels much more efficiently than the respective counterparts derived from SARS-CoV. Nevertheless, ORF7a from both species was able to alter Tetherin glycosylation. The ability to decrease total protein levels of Tetherin was conserved among S proteins from different SARS-CoV-2 variants (α, γ, δ, ο). While SARS-CoV-2 S and ORF7a both colocalized with Tetherin, only ORF7a directly interacted with the restriction factor in a two-hybrid assay. Despite the presence of multiple Tetherin antagonists, SARS-CoV-2 replication in Caco-2 cells was further enhanced upon Tetherin knockout. Altogether, our data show that endogenous Tetherin restricts SARS-CoV-2 replication and that the antiviral activity of Tetherin is only partially counteracted by viral antagonists with differential and complementary modes of action.


Asunto(s)
Antígeno 2 del Estroma de la Médula Ósea , COVID-19 , Coronavirus Relacionado al Síndrome Respiratorio Agudo Severo , Humanos , Células CACO-2 , COVID-19/metabolismo , COVID-19/virología , Proteínas Ligadas a GPI/genética , Proteínas Ligadas a GPI/metabolismo , Células HEK293 , SARS-CoV-2/genética , SARS-CoV-2/metabolismo
20.
Rev. neurol. (Ed. impr.) ; 77(1): 13-18, Jul-Dic. 2023. tab, graf
Artículo en Español | IBECS | ID: ibc-222653

RESUMEN

Objetivo: El objetivo de este estudio es evaluar los efectos de la vacunación contra el SARS-CoV-2 sobre el patrón convulsivo en pacientes pediátricos con epilepsia que acudieron a nuestro centro terciario en la ciudad de Bogotá, Colombia. Pacientes y métodos: Se pidió a los niños con epilepsia que fueron tratados en nuestro centro y que habían recibido la vacuna contra el SARS-CoV-2 y a sus cuidadores que informaran de su experiencia después de la vacunación. Se documentaron la edad, el sexo, la edad de inicio de la epilepsia, la duración de la epilepsia, el tipo de epilepsia, la frecuencia de las convulsiones, el número de medicamentos, el tiempo transcurrido desde la última crisis, los esquemas de vacunación y las convulsiones dos semanas después de la vacunación. Resultados: Se incluyó a 101 pacientes con epilepsia (58%, hombres; y 42%, mujeres). La edad promedio fue de 11 años, el 73% tenía epilepsia focal, y el 27%, generalizada. Veintiuno cumplían los criterios para la epilepsia refractaria y 11 tenían antecedentes personales de convulsiones febriles. Cuarenta y siete pacientes habían sido vacunados con la vacuna de Sinovac; 41, con Pfizer; 12, con Moderna; y uno, con CoronaVac. Tres pacientes presentaron convulsiones 24 horas después de la aplicación de la vacuna sin una relación clara entre la vacunación y la frecuencia de las convulsiones, y un paciente requirió ingreso en el hospital por una convulsión prolongada. Conclusión: La vacunación contra el SARS-CoV-2 en pacientes pediátricos con epilepsia es segura. Aproximadamente el 3% de los pacientes con epilepsia podría eventualmente tener convulsiones en el período posterior a la vacunación.


Aim: The objective of this study is to evaluate effects of SARS-CoV-2 vaccination on seizure pattern in paediatric patients with epilepsy that attended our tertiary center in the city of Bogotá, Colombia. Patients and methods: Children with epilepsy who were treated at our center and have had SARS-CoV-2 vaccination and their caregivers were asked to report their experience following vaccination. We documented age, sex, age at onset of epilepsy, duration of epilepsy, epilepsy type, seizure frequency, number of medications, time from last crisis, vaccination schemes, and seizures two weeks after vaccination. Results: One hundred and one patients with epilepsy were included (58%, male; and 42%, female). The average age was 11 years, 73% had focal epilepsy, and 27%, generalized. Twenty-one fulfilled criteria for refractory epilepsy and 11 had a personal history of febrile seizures. Forty-seven patients had been vaccinated with Sinovac’s vaccine; 41 patients, with Pfizer’s; 12 patients, with Moderna’s; and one, with CoronaVac’s. Three patients presented seizures 24 hours after the application of the vaccine with no clear relation between vaccination and seizure frequency, and one patient required admission to the hospital for a prolonged seizure. Conclusion: Vaccination against SARS-CoV-2 in paediatric patients with epilepsy is safe. Approximately 3% of patients with epilepsy could eventually have seizures in the post-vaccination period.(AU)


Asunto(s)
Humanos , Masculino , Femenino , Niño , Coronavirus Relacionado al Síndrome Respiratorio Agudo Severo , Infecciones por Coronavirus/epidemiología , Infecciones por Coronavirus/inmunología , Pandemias , Epilepsia , Vacunación/efectos adversos , Neurología , Enfermedades del Sistema Nervioso , Pediatría , Colombia , Convulsiones Febriles
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