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1.
Cell ; 187(6): 1363-1373.e12, 2024 Mar 14.
Artículo en Inglés | MEDLINE | ID: mdl-38366591

RESUMEN

In response to the 2022 outbreak of mpox driven by unprecedented human-to-human monkeypox virus (MPXV) transmission, we designed BNT166, aiming to create a highly immunogenic, safe, accessible, and scalable next-generation vaccine against MPXV and related orthopoxviruses. To address the multiple viral forms and increase the breadth of immune response, two candidate multivalent mRNA vaccines were evaluated pre-clinically: a quadrivalent vaccine (BNT166a; encoding the MPXV antigens A35, B6, M1, H3) and a trivalent vaccine (BNT166c; without H3). Both candidates induced robust T cell responses and IgG antibodies in mice, including neutralizing antibodies to both MPXV and vaccinia virus. In challenge studies, BNT166a and BNT166c provided complete protection from vaccinia, clade I, and clade IIb MPXV. Furthermore, immunization with BNT166a was 100% effective at preventing death and at suppressing lesions in a lethal clade I MPXV challenge in cynomolgus macaques. These findings support the clinical evaluation of BNT166, now underway (NCT05988203).


Asunto(s)
Monkeypox virus , Mpox , Vacuna contra Viruela , Animales , Humanos , Ratones , Macaca fascicularis , Monkeypox virus/genética , Mpox/inmunología , Mpox/prevención & control , Vacunas Combinadas , Virus Vaccinia/genética
2.
Cell ; 184(7): 1671-1692, 2021 04 01.
Artículo en Inglés | MEDLINE | ID: mdl-33743212

RESUMEN

The introduction of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) into the human population represents a tremendous medical and economic crisis. Innate immunity-as the first line of defense of our immune system-plays a central role in combating this novel virus. Here, we provide a conceptual framework for the interaction of the human innate immune system with SARS-CoV-2 to link the clinical observations with experimental findings that have been made during the first year of the pandemic. We review evidence that variability in innate immune system components among humans is a main contributor to the heterogeneous disease courses observed for coronavirus disease 2019 (COVID-19), the disease spectrum induced by SARS-CoV-2. A better understanding of the pathophysiological mechanisms observed for cells and soluble mediators involved in innate immunity is a prerequisite for the development of diagnostic markers and therapeutic strategies targeting COVID-19. However, this will also require additional studies addressing causality of events, which so far are lagging behind.


Asunto(s)
COVID-19/inmunología , Interacciones Microbiota-Huesped , Inmunidad Innata , SARS-CoV-2/fisiología , Humanos , Índice de Severidad de la Enfermedad
3.
Cell ; 182(5): 1077-1092, 2020 09 03.
Artículo en Inglés | MEDLINE | ID: mdl-32846157

RESUMEN

Infectious diseases prevalent in humans and animals are caused by pathogens that once emerged from other animal hosts. In addition to these established infections, new infectious diseases periodically emerge. In extreme cases they may cause pandemics such as COVID-19; in other cases, dead-end infections or smaller epidemics result. Established diseases may also re-emerge, for example by extending geographically or by becoming more transmissible or more pathogenic. Disease emergence reflects dynamic balances and imbalances, within complex globally distributed ecosystems comprising humans, animals, pathogens, and the environment. Understanding these variables is a necessary step in controlling future devastating disease emergences.


Asunto(s)
Enfermedades Transmisibles Emergentes/epidemiología , Infecciones por Coronavirus/epidemiología , Neumonía Viral/epidemiología , COVID-19 , Enfermedades Transmisibles Emergentes/prevención & control , Enfermedades Transmisibles Emergentes/transmisión , Infecciones por Coronavirus/prevención & control , Infecciones por Coronavirus/transmisión , Demografía , Ambiente , Interacciones Huésped-Patógeno , Humanos , Pandemias/prevención & control , Neumonía Viral/prevención & control , Neumonía Viral/transmisión
4.
Cell ; 183(3): 739-751.e8, 2020 10 29.
Artículo en Inglés | MEDLINE | ID: mdl-32991842

RESUMEN

The SARS-CoV-2 spike (S) protein variant D614G supplanted the ancestral virus worldwide, reaching near fixation in a matter of months. Here we show that D614G was more infectious than the ancestral form on human lung cells, colon cells, and on cells rendered permissive by ectopic expression of human ACE2 or of ACE2 orthologs from various mammals, including Chinese rufous horseshoe bat and Malayan pangolin. D614G did not alter S protein synthesis, processing, or incorporation into SARS-CoV-2 particles, but D614G affinity for ACE2 was reduced due to a faster dissociation rate. Assessment of the S protein trimer by cryo-electron microscopy showed that D614G disrupts an interprotomer contact and that the conformation is shifted toward an ACE2 binding-competent state, which is modeled to be on pathway for virion membrane fusion with target cells. Consistent with this more open conformation, neutralization potency of antibodies targeting the S protein receptor-binding domain was not attenuated.


Asunto(s)
Betacoronavirus/fisiología , Betacoronavirus/ultraestructura , Glicoproteína de la Espiga del Coronavirus/fisiología , Glicoproteína de la Espiga del Coronavirus/ultraestructura , Enzima Convertidora de Angiotensina 2 , Animales , Anticuerpos Monoclonales/inmunología , Anticuerpos Antivirales/inmunología , Betacoronavirus/patogenicidad , COVID-19 , Células Cultivadas , Infecciones por Coronavirus/virología , Femenino , Variación Genética , Células HEK293 , Humanos , Masculino , Modelos Moleculares , Pandemias , Peptidil-Dipeptidasa A/metabolismo , Neumonía Viral/virología , Conformación Proteica , Procesamiento Proteico-Postraduccional , Receptores de Coronavirus , Receptores Virales/metabolismo , SARS-CoV-2 , Especificidad de la Especie
5.
Immunity ; 57(5): 1160-1176.e7, 2024 May 14.
Artículo en Inglés | MEDLINE | ID: mdl-38697118

RESUMEN

Multimodal single-cell profiling methods can capture immune cell variations unfolding over time at the molecular, cellular, and population levels. Transforming these data into biological insights remains challenging. Here, we introduce a framework to integrate variations at the human population and single-cell levels in vaccination responses. Comparing responses following AS03-adjuvanted versus unadjuvanted influenza vaccines with CITE-seq revealed AS03-specific early (day 1) response phenotypes, including a B cell signature of elevated germinal center competition. A correlated network of cell-type-specific transcriptional states defined the baseline immune status associated with high antibody responders to the unadjuvanted vaccine. Certain innate subsets in the network appeared "naturally adjuvanted," with transcriptional states resembling those induced uniquely by AS03-adjuvanted vaccination. Consistently, CD14+ monocytes from high responders at baseline had elevated phospho-signaling responses to lipopolysaccharide stimulation. Our findings link baseline immune setpoints to early vaccine responses, with positive implications for adjuvant development and immune response engineering.


Asunto(s)
Linfocitos B , Vacunas contra la Influenza , Análisis de la Célula Individual , Humanos , Vacunas contra la Influenza/inmunología , Linfocitos B/inmunología , Centro Germinal/inmunología , Gripe Humana/inmunología , Gripe Humana/prevención & control , Vacunación , Anticuerpos Antivirales/inmunología , Adyuvantes Inmunológicos , Adyuvantes de Vacunas , Monocitos/inmunología , Polisorbatos , Escualeno/inmunología , Inmunidad Innata/inmunología
6.
Immunity ; 55(12): 2405-2418.e7, 2022 12 13.
Artículo en Inglés | MEDLINE | ID: mdl-36356572

RESUMEN

Current influenza vaccines predominantly induce immunity to the hypervariable hemagglutinin (HA) head, requiring frequent vaccine reformulation. Conversely, the immunosubdominant yet conserved HA stem harbors a supersite that is targeted by broadly neutralizing antibodies (bnAbs), representing a prime target for universal vaccines. Here, we showed that the co-immunization of two HA stem immunogens derived from group 1 and 2 influenza A viruses elicits cross-group protective immunity and neutralizing antibody responses in mice, ferrets, and nonhuman primates (NHPs). Immunized mice were protected from multiple group 1 and 2 viruses, and all animal models showed broad serum-neutralizing activity. A bnAb isolated from an immunized NHP broadly neutralized and protected against diverse viruses, including H5N1 and H7N9. Genetic and structural analyses revealed strong homology between macaque and human bnAbs, illustrating common biophysical constraints for acquiring cross-group specificity. Vaccine elicitation of stem-directed cross-group-protective immunity represents a step toward the development of broadly protective influenza vaccines.


Asunto(s)
Subtipo H5N1 del Virus de la Influenza A , Subtipo H7N9 del Virus de la Influenza A , Vacunas contra la Influenza , Gripe Humana , Infecciones por Orthomyxoviridae , Animales , Ratones , Humanos , Hemaglutininas , Anticuerpos ampliamente neutralizantes , Glicoproteínas Hemaglutininas del Virus de la Influenza , Anticuerpos Antivirales , Hurones , Anticuerpos Neutralizantes , Inmunización
7.
Immunity ; 54(3): 557-570.e5, 2021 03 09.
Artículo en Inglés | MEDLINE | ID: mdl-33577760

RESUMEN

The emergence and spread of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has resulted in significant global morbidity, mortality, and societal disruption. A better understanding of virus-host interactions may potentiate therapeutic insights toward limiting this infection. Here we investigated the dynamics of the systemic response to SARS-CoV-2 in hamsters by histological analysis and transcriptional profiling. Infection resulted in consistently high levels of virus in the upper and lower respiratory tracts and sporadic occurrence in other distal tissues. A longitudinal cohort revealed a wave of inflammation, including a type I interferon (IFN-I) response, that was evident in all tissues regardless of viral presence but was insufficient to prevent disease progression. Bolstering the antiviral response with intranasal administration of recombinant IFN-I reduced viral disease, prevented transmission, and lowered inflammation in vivo. This study defines the systemic host response to SARS-CoV-2 infection and supports use of intranasal IFN-I as an effective means of early treatment.


Asunto(s)
COVID-19/metabolismo , COVID-19/virología , Interacciones Huésped-Patógeno , Interferón Tipo I/metabolismo , SARS-CoV-2/fisiología , Animales , Biopsia , COVID-19/genética , COVID-19/inmunología , Cricetinae , Citocinas/genética , Citocinas/metabolismo , Modelos Animales de Enfermedad , Perfilación de la Expresión Génica , Interacciones Huésped-Patógeno/inmunología , Humanos , Inmunidad Innata , Interferón Tipo I/genética , Pulmón/inmunología , Pulmón/metabolismo , Pulmón/patología , Pulmón/virología , Especificidad de Órganos/inmunología , Virulencia , Replicación Viral/inmunología
8.
CA Cancer J Clin ; 70(6): 480-504, 2020 11.
Artículo en Inglés | MEDLINE | ID: mdl-32910493

RESUMEN

The severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has given rise to a pandemic of unprecedented proportions in the modern era because of its highly contagious nature and impact on human health and society: coronavirus disease 2019 (COVID-19). Patients with cardiovascular (CV) risk factors and established CV disease (CVD) are among those initially identified at the highest risk for serious complications, including death. Subsequent studies have pointed out that patients with cancer are also at high risk for a critical disease course. Therefore, the most vulnerable patients are seemingly those with both cancer and CVD, and a careful, unified approach in the evaluation and management of this patient population is especially needed in times of the COVID-19 pandemic. This review provides an overview of the unique implications of the viral outbreak for the field of cardio-oncology and outlines key modifications in the approach to this ever-increasing patient population. These modifications include a shift toward greater utilization of cardiac biomarkers and a more focused CV imaging approach in the broader context of modifications to typical practice pathways. The goal of this strategic adjustment is to minimize the risk of SARS-CoV-2 infection (or other future viral outbreaks) while not becoming negligent of CVD and its important impact on the overall outcomes of patients who are being treated for cancer.


Asunto(s)
Antineoplásicos/efectos adversos , COVID-19/complicaciones , Enfermedades Cardiovasculares/etiología , Infección Hospitalaria/prevención & control , Neoplasias/complicaciones , Neoplasias/terapia , Antraciclinas/efectos adversos , COVID-19/fisiopatología , COVID-19/prevención & control , COVID-19/transmisión , Enfermedades Cardiovasculares/diagnóstico por imagen , Enfermedades Cardiovasculares/terapia , Humanos , Inhibidores de Proteasoma/efectos adversos , Inhibidores de Proteínas Quinasas/efectos adversos , Radioterapia/efectos adversos , Receptor ErbB-2/antagonistas & inhibidores , Derivación y Consulta , SARS-CoV-2 , Trastuzumab/efectos adversos
9.
Proc Natl Acad Sci U S A ; 121(33): e2407322121, 2024 Aug 13.
Artículo en Inglés | MEDLINE | ID: mdl-39110729

RESUMEN

While studies have examined the effects of schools offering in-person learning during the pandemic, this study provides analysis of student enrollment decisions (remote versus in-person) in response to schools providing in-person learning opportunities. In Connecticut during the 2020-21 school year, we find that student take-up of in-person learning opportunities was low with students on average enrolled in-person for only half of the days offered, and take-up was even lower in schools with larger shares of disadvantaged students. The provision of in-person learning opportunities has been previously shown to mitigate pandemic learning losses. By exploiting data on actual enrollment, we show that the protective benefits of in-person learning are twice as large as previously estimated once we account for the low rates of student take-up. Finally, we provide evidence suggesting that a key mechanism behind the benefits of in-person learning is alleviating the burden faced by schools and teachers in delivering remote education. First, we show that the benefits to individual students of their in-person learning are substantially smaller than the overall benefits a student receives from their school average level of in-person enrollment. Second, we show that a combination of remote and in-person learning (hybrid) with a full-time on-line presence of students when at home was worse than hybrid learning with students never or only partially online. This second finding is consistent with qualitative evidence showing that teachers found hybrid learning especially challenging when having to manage both in-person and remote students for the entire class period.


Asunto(s)
COVID-19 , Educación a Distancia , Pandemias , Instituciones Académicas , Estudiantes , Humanos , COVID-19/epidemiología , COVID-19/prevención & control , COVID-19/psicología , Estudiantes/psicología , Educación a Distancia/métodos , Pandemias/prevención & control , Connecticut/epidemiología , Aprendizaje , Adolescente , Femenino , Masculino , Niño , SARS-CoV-2
10.
Annu Rev Med ; 75: 1-11, 2024 Jan 29.
Artículo en Inglés | MEDLINE | ID: mdl-37625124

RESUMEN

The COVID-19 pandemic led to disruption of health services around the world, including cancer services. We carried out a narrative review of the effect of the pandemic on cancer prevention services, including screening. Services were severely affected in the early months of the pandemic, and in some areas are still recovering. Large numbers of additional cancers or additional late-stage cancers have been predicted to arise over the coming years as a result of this disruption. To minimize the effects on cancer outcomes, it is necessary to return as quickly as possible to prepandemic levels of screening and prevention activity or indeed to exceed these levels. The recovery of services should address health inequalities.


Asunto(s)
COVID-19 , Neoplasias , Humanos , Pandemias/prevención & control , Neoplasias/epidemiología , Neoplasias/prevención & control
11.
Proc Natl Acad Sci U S A ; 120(42): e2304545120, 2023 10 17.
Artículo en Inglés | MEDLINE | ID: mdl-37812724

RESUMEN

One of the most well-known yet least understood aspects of the 1918 influenza pandemic is the disproportionately high mortality among young adults. Contemporary accounts further describe the victims as healthy young adults, which is contrary to the understanding of selective mortality, which posits that individuals with the highest frailty within a group are at the greatest risk of death. We use a bioarchaeological approach, combining individual-level information on health and stress gleaned from the skeletal remains of individuals who died in 1918 to determine whether healthy individuals were dying during the 1918 pandemic or whether underlying frailty contributed to an increased risk of mortality. Skeletal data on tibial periosteal new bone formation were obtained from 369 individuals from the Hamann-Todd documented osteological collection in Cleveland, Ohio. Skeletal data were analyzed alongside known age at death using Kaplan-Meier survival and Cox proportional hazards analysis. The results suggest that frail or unhealthy individuals were more likely to die during the pandemic than those who were not frail. During the flu, the estimated hazards for individuals with periosteal lesions that were active at the time of death were over two times higher compared to the control group. The results contradict prior assumptions about selective mortality during the 1918 influenza pandemic. Even among young adults, not everyone was equally likely to die-those with evidence of systemic stress suffered greater mortality. These findings provide time depth to our understanding of how variation in life experiences can impact morbidity and mortality even during a pandemic caused by a novel pathogen.


Asunto(s)
Fragilidad , Gripe Humana , Adulto Joven , Humanos , Fragilidad/epidemiología , Pandemias , Gripe Humana/epidemiología , Morbilidad , Periostio/patología
12.
Proc Natl Acad Sci U S A ; 120(10): e2211422120, 2023 03 07.
Artículo en Inglés | MEDLINE | ID: mdl-36848558

RESUMEN

The two nearby Amazonian cities of Iquitos and Manaus endured explosive COVID-19 epidemics and may well have suffered the world's highest infection and death rates over 2020, the first year of the pandemic. State-of-the-art epidemiological and modeling studies estimated that the populations of both cities came close to attaining herd immunity (>70% infected) at the termination of the first wave and were thus protected. This makes it difficult to explain the more deadly second wave of COVID-19 that struck again in Manaus just months later, simultaneous with the appearance of a new P.1 variant of concern, creating a catastrophe for the unprepared population. It was suggested that the second wave was driven by reinfections, but the episode has become controversial and an enigma in the history of the pandemic. We present a data-driven model of epidemic dynamics in Iquitos, which we also use to explain and model events in Manaus. By reverse engineering the multiple epidemic waves over 2 y in these two cities, the partially observed Markov process model inferred that the first wave left Manaus with a highly susceptible and vulnerable population (≈40% infected) open to invasion by P.1, in contrast to Iquitos (≈72% infected). The model reconstructed the full epidemic outbreak dynamics from mortality data by fitting a flexible time-varying reproductive number [Formula: see text] while estimating reinfection and impulsive immune evasion. The approach is currently highly relevant given the lack of tools available to assess these factors as new SARS-CoV-2 virus variants appear with different degrees of immune evasion.


Asunto(s)
COVID-19 , Humanos , COVID-19/epidemiología , SARS-CoV-2/genética , Ciudades/epidemiología , Pandemias
13.
Proc Natl Acad Sci U S A ; 120(46): e2303640120, 2023 Nov 14.
Artículo en Inglés | MEDLINE | ID: mdl-37943837

RESUMEN

The COVID-19 pandemic struck societies directly and indirectly, not just challenging population health but disrupting many aspects of life. Different effects of the spreading virus-and the measures to fight it-are reported and discussed in different scientific fora, with hard-to-compare methods and metrics from different traditions. While the pandemic struck some groups more than others, it is difficult to assess the comprehensive impact on social inequalities. This paper gauges social inequalities using individual-level administrative data for Sweden's entire population. We describe and analyze the relative risks for different social groups in four dimensions-gender, education, income, and world region of birth-to experience three types of COVID-19 incidence, as well as six additional negative life outcomes that reflect general health, access to medical care, and economic strain. During the pandemic, the overall population faced severe morbidity and mortality from COVID-19 and saw higher all-cause mortality, income losses and unemployment risks, as well as reduced access to medical care. These burdens fell more heavily on individuals with low income or education and on immigrants. Although these vulnerable groups experienced larger absolute risks of suffering the direct and indirect consequences of the pandemic, the relative risks in pandemic years (2020 and 2021) were conspicuously similar to those in prepandemic years (2016 to 2019).


Asunto(s)
COVID-19 , Humanos , COVID-19/epidemiología , Pandemias , Suecia/epidemiología , Riesgo , Clase Social
14.
Proc Natl Acad Sci U S A ; 120(33): e2301926120, 2023 08 15.
Artículo en Inglés | MEDLINE | ID: mdl-37552753

RESUMEN

Swine are a primary source for the emergence of pandemic influenza A viruses. The intensification of swine production, along with global trade, has amplified the transmission and zoonotic risk of swine influenza A virus (swIAV). Effective surveillance is essential to uncover emerging virus strains; however gaps remain in our understanding of the swIAV genomic landscape in Southeast Asia. More than 4,000 nasal swabs were collected from pigs in Cambodia, yielding 72 IAV-positive samples by RT-qPCR and 45 genomic sequences. We unmasked the cocirculation of multiple lineages of genetically diverse swIAV of pandemic concern. Genomic analyses revealed a novel European avian-like H1N2 swIAV reassortant variant with North American triple reassortant internal genes, that emerged approximately seven years before its first detection in pigs in 2021. Using phylogeographic reconstruction, we identified south central China as the dominant source of swine viruses disseminated to other regions in China and Southeast Asia. We also identified nine distinct swIAV lineages in Cambodia, which diverged from their closest ancestors between two and 15 B.P., indicating significant undetected diversity in the region, including reverse zoonoses of human H1N1/2009 pandemic and H3N2 viruses. A similar period of cryptic circulation of swIAVs occurred in the decades before the H1N1/2009 pandemic. The hidden diversity of swIAV observed here further emphasizes the complex underlying evolutionary processes present in this region, reinforcing the importance of genomic surveillance at the human-swine interface for early warning of disease emergence to avoid future pandemics.


Asunto(s)
Subtipo H1N1 del Virus de la Influenza A , Virus de la Influenza A , Gripe Humana , Infecciones por Orthomyxoviridae , Enfermedades de los Porcinos , Porcinos , Animales , Humanos , Subtipo H3N2 del Virus de la Influenza A/genética , Subtipo H1N1 del Virus de la Influenza A/genética , Virus Reordenados/genética , Infecciones por Orthomyxoviridae/epidemiología , Infecciones por Orthomyxoviridae/veterinaria , Gripe Humana/epidemiología , Virus de la Influenza A/genética , Genómica , Filogenia , Cambodia/epidemiología , Enfermedades de los Porcinos/epidemiología
15.
Proc Natl Acad Sci U S A ; 120(19): e2300717120, 2023 05 09.
Artículo en Inglés | MEDLINE | ID: mdl-37126673

RESUMEN

Every country in Europe experienced an adverse impact from the COVID-19 pandemic on life satisfaction, though on average, satisfaction with life in the summer of 2022 is about the same as the pre-pandemic value in the autumn of 2019. Typically, an upsurge in the severity of the pandemic (measured by the number of COVID-related deaths) is associated with declining life satisfaction and an ebbing, with increasing life satisfaction. Of the three waves of the pandemic between March 2020 and the autumn of 2022, the most severe impact typically occurred in 2021 during the second wave; in the third wave, the response declined due to the spread of effective vaccines and the takeover of omicron variants.


Asunto(s)
COVID-19 , Humanos , Pandemias , SARS-CoV-2 , Europa (Continente)
16.
Proc Natl Acad Sci U S A ; 120(14): e2216207120, 2023 04 04.
Artículo en Inglés | MEDLINE | ID: mdl-36972447

RESUMEN

In this study, we examined emotional distress using annual representative survey data from 1.53 million individuals surveyed in 113 countries from 2009 to 2021. Participants reported whether they had experienced worry, sadness, stress, or anger during a lot of the previous day. Within-country estimates showed that the prevalence of feelings of emotional distress increased from 25 to 31% between 2009 and 2021, with those with low levels of education and income experiencing the largest increases in distress. On a global level, the pandemic period was characterized by an initial increase in distress in 2020 followed by recovery in 2021.


Asunto(s)
Distrés Psicológico , Estrés Psicológico , Humanos , Estrés Psicológico/epidemiología , Estrés Psicológico/psicología , Emociones , Renta , Ira , Pandemias
17.
Immunol Rev ; 309(1): 8-11, 2022 08.
Artículo en Inglés | MEDLINE | ID: mdl-35770708

RESUMEN

Pandemics have devastating effects that can be mitigated with the existence of global infrastructure for pandemic preparedness along with the adaptation of existing research studies and establishment of biorepositories early in an outbreak. Observational cohort studies in place prior to a pandemic, that are rapidly scalable in response to emerging infectious diseases, are essential for both the early pandemic response and evaluation of its long-term effects. The ability to quickly collect and share samples from convalescent individuals is also critical for the development of vaccines and therapeutics. We provide a reflection on key lessons learned from establishing a longitudinal observational cohort study during the SARS-CoV-2 pandemic in order to provide guidance for future pandemic preparedness.


Asunto(s)
COVID-19 , Pandemias , Estudios de Cohortes , Brotes de Enfermedades , Humanos , Estudios Observacionales como Asunto , Pandemias/prevención & control , SARS-CoV-2
18.
J Biol Chem ; : 107884, 2024 Oct 10.
Artículo en Inglés | MEDLINE | ID: mdl-39395809

RESUMEN

Although COVID-19 pandemic was declared no longer a global emergency by the World Health Organization in May 2023, SARS-CoV-2 is still infecting people across the world. Many therapeutic oligonucleotides such as ASOs, siRNAs or CRISPR-based systems emerged as promising antiviral strategies for the treatment of SARS-CoV-2. In this work we explored the inhibitory potential on SARS-CoV-2 replication of Polypurine Reverse Hoogsteen Hairpins (PPRHs), CC1-PPRH and CC3-PPRH, targeting specific polypyrimidine sequences within the replicase and Spike regions, respectively, and previously validated for COVID-19 diagnosis. Both PPRHs bound to their target sequences in the viral genome with high affinity in the order of nM. In vitro, both PPRHs reduced viral replication by more than 92% when transfected into VERO-E6 cells 24 hours prior infection with SARS-CoV-2. In vivo intranasal administration of CC1-PPRH in K18-hACE2 mice expressing the human ACE receptor protected all the animals from SARS-CoV-2 infection. The properties of PPRHs position them as promising candidates for the development of novel therapeutics against SARS-CoV-2 and other viral infections.

19.
J Biol Chem ; 300(8): 107514, 2024 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-38945449

RESUMEN

The development of safe and effective broad-spectrum antivirals that target the replication machinery of respiratory viruses is of high priority in pandemic preparedness programs. Here, we studied the mechanism of action of a newly discovered nucleotide analog against diverse RNA-dependent RNA polymerases (RdRps) of prototypic respiratory viruses. GS-646939 is the active 5'-triphosphate metabolite of a 4'-cyano modified C-adenosine analog phosphoramidate prodrug GS-7682. Enzyme kinetics show that the RdRps of human rhinovirus type 16 (HRV-16) and enterovirus 71 incorporate GS-646939 with unprecedented selectivity; GS-646939 is incorporated 20-50-fold more efficiently than its natural ATP counterpart. The RdRp complex of respiratory syncytial virus and human metapneumovirus incorporate GS-646939 and ATP with similar efficiency. In contrast, influenza B RdRp shows a clear preference for ATP and human mitochondrial RNA polymerase does not show significant incorporation of GS-646939. Once incorporated into the nascent RNA strand, GS-646939 acts as a chain terminator although higher NTP concentrations can partially overcome inhibition for some polymerases. Modeling and biochemical data suggest that the 4'-modification inhibits RdRp translocation. Comparative studies with GS-443902, the active triphosphate form of the 1'-cyano modified prodrugs remdesivir and obeldesivir, reveal not only different mechanisms of inhibition, but also differences in the spectrum of inhibition of viral polymerases. In conclusion, 1'-cyano and 4'-cyano modifications of nucleotide analogs provide complementary strategies to target the polymerase of several families of respiratory RNA viruses.


Asunto(s)
Antivirales , ARN Polimerasa Dependiente del ARN , Humanos , Antivirales/farmacología , Antivirales/química , ARN Polimerasa Dependiente del ARN/antagonistas & inhibidores , ARN Polimerasa Dependiente del ARN/metabolismo , ARN Polimerasa Dependiente del ARN/química , Virus ARN/efectos de los fármacos , Virus ARN/enzimología , Metapneumovirus/efectos de los fármacos , Nucleótidos/química , Nucleótidos/farmacología , Nucleótidos/metabolismo
20.
J Virol ; 98(9): e0124024, 2024 Sep 17.
Artículo en Inglés | MEDLINE | ID: mdl-39087765

RESUMEN

Science is humanity's best insurance against threats from nature, but it is a fragile enterprise that must be nourished and protected. The preponderance of scientific evidence indicates a natural origin for SARS-CoV-2. Yet, the theory that SARS-CoV-2 was engineered in and escaped from a lab dominates media attention, even in the absence of strong evidence. We discuss how the resulting anti-science movement puts the research community, scientific research, and pandemic preparedness at risk.


Asunto(s)
COVID-19 , SARS-CoV-2 , Humanos , COVID-19/virología , COVID-19/transmisión , Pandemias , Animales
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