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2.
Science ; 371(6527): 347-348, 2021 Jan 22.
Artigo em Inglês | MEDLINE | ID: mdl-33479140
3.
J Exp Med ; 218(3)2021 03 01.
Artigo em Inglês | MEDLINE | ID: mdl-33433624

RESUMO

Although COVID-19 is considered to be primarily a respiratory disease, SARS-CoV-2 affects multiple organ systems including the central nervous system (CNS). Yet, there is no consensus on the consequences of CNS infections. Here, we used three independent approaches to probe the capacity of SARS-CoV-2 to infect the brain. First, using human brain organoids, we observed clear evidence of infection with accompanying metabolic changes in infected and neighboring neurons. However, no evidence for type I interferon responses was detected. We demonstrate that neuronal infection can be prevented by blocking ACE2 with antibodies or by administering cerebrospinal fluid from a COVID-19 patient. Second, using mice overexpressing human ACE2, we demonstrate SARS-CoV-2 neuroinvasion in vivo. Finally, in autopsies from patients who died of COVID-19, we detect SARS-CoV-2 in cortical neurons and note pathological features associated with infection with minimal immune cell infiltrates. These results provide evidence for the neuroinvasive capacity of SARS-CoV-2 and an unexpected consequence of direct infection of neurons by SARS-CoV-2.


Assuntos
Anticorpos Bloqueadores/química , Córtex Cerebral , Neurônios , /metabolismo , /antagonistas & inibidores , Animais , /patologia , Córtex Cerebral/metabolismo , Córtex Cerebral/patologia , Córtex Cerebral/virologia , Modelos Animais de Doenças , Feminino , Humanos , Masculino , Camundongos , Pessoa de Meia-Idade , Neurônios/metabolismo , Neurônios/patologia , Neurônios/virologia , Organoides/metabolismo , Organoides/patologia , Organoides/virologia
5.
Cell ; 183(5): 1312-1324.e10, 2020 Nov 25.
Artigo em Inglês | MEDLINE | ID: mdl-33212011

RESUMO

Interferon (IFN)-Is are crucial mediators of antiviral immunity and homeostatic immune system regulation. However, the source of IFN-I signaling under homeostatic conditions is unclear. We discovered that commensal microbes regulate the IFN-I response through induction of IFN-ß by colonic DCs. Moreover, the mechanism by which a specific commensal microbe induces IFN-ß was identified. Outer membrane (OM)-associated glycolipids of gut commensal microbes belonging to the Bacteroidetes phylum induce expression of IFN-ß. Using Bacteroides fragilis and its OM-associated polysaccharide A, we determined that IFN-ß expression was induced via TLR4-TRIF signaling. Antiviral activity of this purified microbial molecule against infection with either vesicular stomatitis virus (VSV) or influenza was demonstrated to be dependent on the induction of IFN-ß. In a murine VSV infection model, commensal-induced IFN-ß regulated natural resistance to virus infection. Due to the physiological importance of IFN-Is, discovery of an IFN-ß-inducing microbial molecule represents a potential approach for the treatment of some human diseases.

7.
PLoS Biol ; 18(10): e3000867, 2020 10.
Artigo em Inglês | MEDLINE | ID: mdl-33027248

RESUMO

The current quantitative reverse transcription PCR (RT-qPCR) assay recommended for severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) testing in the United States requires analysis of 3 genomic targets per sample: 2 viral and 1 host. To simplify testing and reduce the volume of required reagents, we devised a multiplex RT-qPCR assay to detect SARS-CoV-2 in a single reaction. We used existing N1, N2, and RP primer and probe sets by the Centers for Disease Control and Prevention, but substituted fluorophores to allow multiplexing of the assay. The cycle threshold (Ct) values of our multiplex RT-qPCR were comparable to those obtained by the single assay adapted for research purposes. Low copy numbers (≥500 copies/reaction) of SARS-CoV-2 RNA were consistently detected by the multiplex RT-qPCR. Our novel multiplex RT-qPCR improves upon current single diagnostics by saving reagents, costs, time, and labor.


Assuntos
Betacoronavirus/genética , Técnicas de Laboratório Clínico/métodos , Infecções por Coronavirus/diagnóstico , Reação em Cadeia da Polimerase Multiplex/normas , Pneumonia Viral/diagnóstico , RNA Viral/genética , Kit de Reagentes para Diagnóstico/normas , Reação em Cadeia da Polimerase Via Transcriptase Reversa/normas , Betacoronavirus/patogenicidade , Estudos de Casos e Controles , Técnicas de Laboratório Clínico/normas , Infecções por Coronavirus/virologia , Primers do DNA/normas , Células HEK293 , Humanos , Limite de Detecção , Nasofaringe/virologia , Pandemias , Pneumonia Viral/virologia , Estados Unidos
8.
Lancet Infect Dis ; 2020 Oct 12.
Artigo em Inglês | MEDLINE | ID: mdl-33058796
9.
J Virol ; 94(22)2020 Oct 27.
Artigo em Inglês | MEDLINE | ID: mdl-32878886

RESUMO

Herpes simplex virus 1 (HSV-1) and HSV-2 can efficiently establish lifelong, transcriptionally silent latency states in sensory neurons to escape host detection. While host factors have previously been associated with long-range insulators in the viral genome, it is still unknown whether host transcription factors can repress viral genes more proximately to promote latency in dorsal root ganglion (DRG) neurons. Here, we assessed whether RUNX (runt-related transcription factor) transcription factors, which are critical in the development of sensory neurons, could be binding HSV-1 genome directly to suppress viral gene expression and lytic infection. Using previously published transcriptome sequencing data, we confirmed that mouse DRG neurons highly express Runx1 mRNA. Through computational analysis of HSV-1 and HSV-2 genomes, we observed that putative RUNX consensus binding sites (CBSs) were more enriched and more closely located to viral gene transcription start sites than would be expected by chance. We further found that RUNX CBSs were significantly more enriched among genomes of herpesviruses compared to those of nonherpesviruses. Utilizing an in vitro model of HSV-1 infection, we found that overexpressed RUNX1 could bind putative binding sites in the HSV-1 genome, repress numerous viral genes spanning all three kinetic classes, and suppress productive infection. In contrast, knockdown of RUNX1 in neuroblastoma cells induced viral gene expression and increased HSV-1 infection in vitro In sum, these data support a novel role for RUNX1 in directly binding herpesvirus genome, silencing the transcription of numerous viral genes, and ultimately limiting overall infection.IMPORTANCE Infecting 90% of the global population, HSV-1 and HSV-2 represent some of the most prevalent viruses in the world. Much of their success can be attributed to their ability to establish lifelong latent infections in the dorsal root ganglia (DRG). It is still largely unknown, however, how host transcription factors are involved in establishing this latency. Here, we report that RUNX1, expressed highly in DRG, binds HSV-1 genome, represses transcription of numerous viral genes, and suppresses productive in vitro infection. Our computational work further suggests this strategy may be used by other herpesviruses to reinforce latency in a cell-specific manner.

10.
bioRxiv ; 2020 Sep 12.
Artigo em Inglês | MEDLINE | ID: mdl-32935102

RESUMO

A subset of patients with COVID-19 display neurologic symptoms but it remains unknown whether SARS-CoV-2 damages the central nervous system (CNS) directly through neuroinvasion, or if neurological symptoms are due to secondary mechanisms, including immune-mediated effects. Here, we examined the immune milieu in the CNS through the analysis of cerebrospinal fluid (CSF) and in circulation through analysis of peripheral blood mononuclear cells (PBMCs) of COVID-19 patients with neurological symptoms. Single cell sequencing with paired repertoire sequencing of PBMCs and CSF cells show evidence for unique immune response to SARS-CoV-2 in the CNS. Strikingly, anti-SARS-CoV-2 antibodies are present in the CSF of all patients studied, but the antibody epitope specificity in the CSF and relative prevalence of B cell receptor sequences markedly differed when compared to those found in paired serum. Finally, using a mouse model of SARS-CoV-2 infection, we demonstrate that localized CNS immune responses occur following viral neuroinvasion, and that the CSF is a faithful surrogate for responses occurring uniquely in the CNS. These results illuminate CNS compartment-specific immune responses to SARS-CoV-2, forming the basis for informed treatment of neurological symptoms associated with COVID-19.

11.
bioRxiv ; 2020 Sep 08.
Artigo em Inglês | MEDLINE | ID: mdl-32935108

RESUMO

Although COVID-19 is considered to be primarily a respiratory disease, SARS-CoV-2 affects multiple organ systems including the central nervous system (CNS). Yet, there is no consensus whether the virus can infect the brain, or what the consequences of CNS infection are. Here, we used three independent approaches to probe the capacity of SARS-CoV-2 to infect the brain. First, using human brain organoids, we observed clear evidence of infection with accompanying metabolic changes in the infected and neighboring neurons. However, no evidence for the type I interferon responses was detected. We demonstrate that neuronal infection can be prevented either by blocking ACE2 with antibodies or by administering cerebrospinal fluid from a COVID-19 patient. Second, using mice overexpressing human ACE2, we demonstrate in vivo that SARS-CoV-2 neuroinvasion, but not respiratory infection, is associated with mortality. Finally, in brain autopsy from patients who died of COVID-19, we detect SARS-CoV-2 in the cortical neurons, and note pathologic features associated with infection with minimal immune cell infiltrates. These results provide evidence for the neuroinvasive capacity of SARS-CoV2, and an unexpected consequence of direct infection of neurons by SARS-CoV-2.

12.
medRxiv ; 2020 Sep 08.
Artigo em Inglês | MEDLINE | ID: mdl-32935119

RESUMO

Coronavirus disease-2019 (COVID-19) has poorer clinical outcomes in males compared to females, and immune responses underlie these sex-related differences in disease trajectory. As immune responses are in part regulated by metabolites, we examined whether the serum metabolome has sex-specificity for immune responses in COVID-19. In males with COVID- 19, kynurenic acid (KA) and a high KA to kynurenine (K) ratio was positively correlated with age, inflammatory cytokines, and chemokines and was negatively correlated with T cell responses, revealing that KA production is linked to immune responses in males. Males that clinically deteriorated had a higher KA:K ratio than those that stabilized. In females with COVID-19, this ratio positively correlated with T cell responses and did not correlate with age or clinical severity. KA is known to inhibit glutamate release, and we observed that serum glutamate is lower in patients that deteriorate from COVID-19 compared to those that stabilize, and correlates with immune responses. Analysis of Genotype-Tissue Expression (GTEx) data revealed that expression of kynurenine aminotransferase, which regulates KA production, correlates most strongly with cytokine levels and aryl hydrocarbon receptor activation in older males. This study reveals that KA has a sex-specific link to immune responses and clinical outcomes, in COVID-19 infection.

13.
medRxiv ; 2020 Sep 10.
Artigo em Inglês | MEDLINE | ID: mdl-32935121

RESUMO

BACKGROUND: Healthcare workers (HCW) treating COVID-19 patients are at high risk for infection and may also spread infection through their contact with vulnerable patients. Smell loss has been associated with SARS-CoV-2 infection, but it is unknown whether monitoring for smell loss can be used to identify asymptomatic infection among high risk individuals, like HCW. METHODS: We performed a prospective cohort study, tracking 473 HCW across three months to determine if smell loss could predict SARS-CoV-2 infection in this high-risk group. HCW subjects completed a longitudinal, novel behavioral at-home assessment of smell function with household items, as well as detailed symptom surveys that included a parosmia screening questionnaire, and RT-qPCR testing to identify SARS-CoV-2 infection. RESULTS: SARS-CoV-2 was identified in 17 (3.6%) of 473 HCW. Among the 17 infected HCW, 53% reported smell loss, and were more likely to report smell loss than COVID-negative HCW on both the at-home assessment and the screening questionnaire (P < .01). 67% reported smell loss prior to having a positive SARS-CoV-2 test, and smell loss was reported a median of two days before testing positive. Neurological symptoms were reported more frequently among COVID-positive HCW who reported smell loss (P < .01). CONCLUSIONS: In this prospective study of HCW, self-reported changes in smell using two different measures were predictive of COVID-19 infection. Smell loss frequently preceded a positive test and was associated with neurological symptoms.

14.
medRxiv ; 2020 Sep 03.
Artigo em Inglês | MEDLINE | ID: mdl-32909003

RESUMO

Expanding testing capabilities is integral to managing the further spread of SARS-CoV-2 and developing reopening strategies, particularly in regards to identifying and isolating asymptomatic and pre-symptomatic individuals. Central to meeting testing demands are specimens that can be easily and reliably collected and laboratory capacity to rapidly ramp up to scale. We and others have demonstrated that high and consistent levels of SARS-CoV-2 RNA can be detected in saliva from COVID-19 inpatients, outpatients, and asymptomatic individuals. As saliva collection is non-invasive, extending this strategy to test pooled saliva samples from multiple individuals could thus provide a simple method to expand testing capacity. However, hesitation towards pooled sample testing arises due to the dilution of positive samples, potentially shifting weakly positive samples below the detection limit for SARS-CoV-2 and thereby decreasing the sensitivity. Here, we investigated the potential of pooling saliva samples by 5, 10, and 20 samples prior to RNA extraction and RT-qPCR detection of SARS-CoV-2. Based on samples tested, we conservatively estimated a reduction of 7.41%, 11.11%, and 14.81% sensitivity, for each of the pool sizes, respectively. Using these estimates we modeled anticipated changes in RT-qPCR cycle threshold to show the practical impact of pooling on results of SARS-CoV-2 testing. In tested populations with greater than 3% prevalence, testing samples in pools of 5 requires the least overall number of tests. Below 1% however, pools of 10 or 20 are more beneficial and likely more supportive of ongoing surveillance strategies.

15.
J Exp Med ; 217(12)2020 12 07.
Artigo em Inglês | MEDLINE | ID: mdl-32750141

RESUMO

Severe acute respiratory syndrome-coronavirus 2 (SARS-Cov-2) has caused over 13,000,000 cases of coronavirus disease (COVID-19) with a significant fatality rate. Laboratory mice have been the stalwart of therapeutic and vaccine development; however, they do not support infection by SARS-CoV-2 due to the virus's inability to use the mouse orthologue of its human entry receptor angiotensin-converting enzyme 2 (hACE2). While hACE2 transgenic mice support infection and pathogenesis, these mice are currently limited in availability and are restricted to a single genetic background. Here we report the development of a mouse model of SARS-CoV-2 based on adeno-associated virus (AAV)-mediated expression of hACE2. These mice support viral replication and exhibit pathological findings found in COVID-19 patients. Moreover, we show that type I interferons do not control SARS-CoV-2 replication in vivo but are significant drivers of pathological responses. Thus, the AAV-hACE2 mouse model enables rapid deployment for in-depth analysis following robust SARS-CoV-2 infection with authentic patient-derived virus in mice of diverse genetic backgrounds.


Assuntos
Betacoronavirus/metabolismo , Infecções por Coronavirus/metabolismo , Modelos Animais de Doenças , Interferon Tipo I/metabolismo , Camundongos/genética , Peptidil Dipeptidase A/metabolismo , Pneumonia Viral/metabolismo , Animais , Linhagem Celular Tumoral , Infecções por Coronavirus/patologia , Infecções por Coronavirus/virologia , Dependovirus/genética , Feminino , Humanos , Inflamação/metabolismo , Pulmão/patologia , Pulmão/virologia , Masculino , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , Pandemias , Infecções por Parvoviridae/metabolismo , Infecções por Parvoviridae/virologia , Peptidil Dipeptidase A/genética , Pneumonia Viral/patologia , Pneumonia Viral/virologia , Transdução de Sinais/genética , Replicação Viral/genética
16.
medRxiv ; 2020 Jul 21.
Artigo em Inglês | MEDLINE | ID: mdl-32743602

RESUMO

Objective: Severe acute respiratory syndrome virus (SARS-CoV-2) has infected millions of people worldwide. Our goal was to identify risk factors associated with admission and disease severity in patients with SARS-CoV-2. Design: This was an observational, retrospective study based on real-world data for 7,995 patients with SARS-CoV-2 from a clinical data repository. Setting: Yale New Haven Health (YNHH) is a five-hospital academic health system serving a diverse patient population with community and teaching facilities in both urban and suburban areas. Populations: The study included adult patients who had SARS-CoV-2 testing at YNHH between March 1 and April 30, 2020. Main outcome and performance measures: Primary outcomes were admission and in-hospital mortality for patients with SARS-CoV-2 infection as determined by RT-PCR testing. We also assessed features associated with the need for respiratory support. Results: Of the 28605 patients tested for SARS-CoV-2, 7995 patients (27.9%) had an infection (median age 52.3 years) and 2154 (26.9%) of these had an associated admission (median age 66.2 years). Of admitted patients, 1633 (75.8%) had a discharge disposition at the end of the study period. Of these, 192 (11.8%) required invasive mechanical ventilation and 227 (13.5%) expired. Increased age and male sex were positively associated with admission and in-hospital mortality (median age 81.9 years), while comorbidities had a much weaker association with the risk of admission or mortality. Black race (OR 1.43, 95%CI 1.14-1.78) and Hispanic ethnicity (OR 1.81, 95%CI 1.50-2.18) were identified as risk factors for admission, but, among discharged patients, age-adjusted in-hospital mortality was not significantly different among racial and ethnic groups. Conclusions: This observational study identified, among people testing positive for SARS-CoV-2 infection, older age and male sex as the most strongly associated risks for admission and in-hospital mortality in patients with SARS-CoV-2 infection. While minority racial and ethnic groups had increased burden of disease and risk of admission, age-adjusted in-hospital mortality for discharged patients was not significantly different among racial and ethnic groups. Ongoing studies will be needed to continue to evaluate these risks, particularly in the setting of evolving treatment guidelines.

17.
Nature ; 588(7837): 315-320, 2020 12.
Artigo em Inglês | MEDLINE | ID: mdl-32846427

RESUMO

There is increasing evidence that coronavirus disease 2019 (COVID-19) produces more severe symptoms and higher mortality among men than among women1-5. However, whether immune responses against severe acute respiratory syndrome coronavirus (SARS-CoV-2) differ between sexes, and whether such differences correlate with the sex difference in the disease course of COVID-19, is currently unknown. Here we examined sex differences in viral loads, SARS-CoV-2-specific antibody titres, plasma cytokines and blood-cell phenotyping in patients with moderate COVID-19 who had not received immunomodulatory medications. Male patients had higher plasma levels of innate immune cytokines such as IL-8 and IL-18 along with more robust induction of non-classical monocytes. By contrast, female patients had more robust T cell activation than male patients during SARS-CoV-2 infection. Notably, we found that a poor T cell response negatively correlated with patients' age and was associated with worse disease outcome in male patients, but not in female patients. By contrast, higher levels of innate immune cytokines were associated with worse disease progression in female patients, but not in male patients. These findings provide a possible explanation for the observed sex biases in COVID-19, and provide an important basis for the development of a sex-based approach to the treatment and care of male and female patients with COVID-19.

20.
medRxiv ; 2020 Aug 04.
Artigo em Inglês | MEDLINE | ID: mdl-32793924

RESUMO

Most currently approved strategies for the collection of saliva for COVID-19 diagnostics require specialized tubes containing buffers promoted for the stabilization of SARS-CoV-2 RNA and virus inactivation. Yet many of these are expensive, in limited supply, and not necessarily validated specifically for viral RNA. While saliva is a promising sample type as it can be reliably self-collected for the sensitive detection of SARS-CoV-2, the expense and availability of these collection tubes are prohibitive to mass testing efforts. Therefore, we investigated the stability of SARS-CoV-2 RNA and infectious virus detection from saliva without supplementation. We tested RNA stability over extended periods of time (2-25 days) and at temperatures representing at-home storage and elevated temperatures which might be experienced when cold chain transport may be unavailable. We found SARS-CoV-2 RNA in saliva from infected individuals is stable at 4°C, room temperature (~19°C), and 30°C for prolonged periods and found limited evidence for viral replication in saliva. This work demonstrates that expensive saliva collection options involving RNA stabilization and virus inactivation buffers are not always needed, permitting the use of cheaper collection options. Affordable testing methods are urgently needed to meet current testing demands and for continued surveillance in reopening strategies.

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