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2.
JCO Oncol Pract ; : OP2300657, 2024 May 02.
Artigo em Inglês | MEDLINE | ID: mdl-38696740

RESUMO

PURPOSE: In Southeastern Ontario, increased patient distance from the regional lung cancer diagnostic assessment program (LDAP) is associated with a lower likelihood of patient care via LDAP while receiving care via LDAP is associated with improved survival. We implemented an LDAP outreach clinic to provide specialist assessment for patients with suspected lung cancer at a regional community hospital and assessed the impact on timeliness and accessibility of care. MATERIALS AND METHODS: The Kingston Health Sciences Centre LDAP team engaged with community hospital partners to develop and launch the LDAP outreach clinic. We performed a retrospective chart review of LDAP patients (N = 1,070) before (August-November 2021; n = 234) and after implementation of the outreach clinic (November 2021-October 2022; n = 836). Descriptive data are reported as No. (%). Unpaired t tests and statistical process control charts assess for significance. A cost analysis of out-of-pocket patient costs related to travel and parking is presented in 2022 Canadian dollars (CAD). RESULTS: Compared with a 3-month matched time period before (August-October 2021) and after outreach clinic (August-October 2022), the mean time from referral to assessment and time from referral to diagnosis decreased from 20.3 to 14.4 days (P = .0019) and 40.0 to 28.9 days (P = .0007), respectively. Over 12 months, the total patient travel was reduced by 8,856 km, which combined with parking cost-savings, resulted in patient out-of-pocket savings of CAD $5,755.60 (CAD $47.60/patient). Accounting for physician travel, the total travel saved was 5,688 km, corresponding to reduced CO2 emissions by 1.9 tCO2. CONCLUSION: Implementation of a lung cancer outreach clinic led to improved timeliness of care, patient cost-savings, and reduced carbon footprint while serving patients in their community.

3.
Signal Transduct Target Ther ; 8(1): 385, 2023 10 09.
Artigo em Inglês | MEDLINE | ID: mdl-37806990

RESUMO

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), the causative agent of coronavirus disease 2019 (COVID-19), has had a significant impact on healthcare systems and economies worldwide. The continuous emergence of new viral strains presents a major challenge in the development of effective antiviral agents. Strategies that possess broad-spectrum antiviral activities are desirable to control SARS-CoV-2 infection. ACE2, an angiotensin-containing enzyme that prevents the overactivation of the renin angiotensin system, is the receptor for SARS-CoV-2. ACE2 interacts with the spike protein and facilitates viral attachment and entry into host cells. Yet, SARS-CoV-2 infection also promotes ACE2 degradation. Whether restoring ACE2 surface expression has an impact on SARS-CoV-2 infection is yet to be determined. Here, we show that the ACE2-spike complex is endocytosed and degraded via autophagy in a manner that depends on clathrin-mediated endocytosis and PAK1-mediated cytoskeleton rearrangement. In contrast, free cellular spike protein is selectively cleaved into S1 and S2 subunits in a lysosomal-dependent manner. Importantly, we show that the pan-PAK inhibitor FRAX-486 restores ACE2 surface expression and suppresses infection by different SARS-CoV-2 strains. FRAX-486-treated Syrian hamsters exhibit significantly decreased lung viral load and alleviated pulmonary inflammation compared with untreated hamsters. In summary, our findings have identified novel pathways regulating viral entry, as well as therapeutic targets and candidate compounds for controlling the emerging strains of SARS-CoV-2 infection.


Assuntos
COVID-19 , SARS-CoV-2 , Internalização do Vírus , Quinases Ativadas por p21 , Humanos , Enzima de Conversão de Angiotensina 2/metabolismo , COVID-19/patologia , COVID-19/virologia , Citoesqueleto , Quinases Ativadas por p21/metabolismo , Peptidil Dipeptidase A/metabolismo , SARS-CoV-2/metabolismo , Glicoproteína da Espícula de Coronavírus/genética , Glicoproteína da Espícula de Coronavírus/metabolismo , Tratamento Farmacológico da COVID-19
4.
Immunity ; 56(10): 2442-2455.e8, 2023 Oct 10.
Artigo em Inglês | MEDLINE | ID: mdl-37776849

RESUMO

SARS-CoV-2 continues to evolve, with many variants evading clinically authorized antibodies. To isolate monoclonal antibodies (mAbs) with broadly neutralizing capacities against the virus, we screened serum samples from convalescing COVID-19 patients. We isolated two mAbs, 12-16 and 12-19, which neutralized all SARS-CoV-2 variants tested, including the XBB subvariants, and prevented infection in hamsters challenged with Omicron BA.1 intranasally. Structurally, both antibodies targeted a conserved quaternary epitope located at the interface between the N-terminal domain and subdomain 1, uncovering a site of vulnerability on SARS-CoV-2 spike. These antibodies prevented viral receptor engagement by locking the receptor-binding domain (RBD) of spike in the down conformation, revealing a mechanism of virus neutralization for non-RBD antibodies. Deep mutational scanning showed that SARS-CoV-2 could mutate to escape 12-19, but such mutations are rarely found in circulating viruses. Antibodies 12-16 and 12-19 hold promise as prophylactic agents for immunocompromised persons who do not respond robustly to COVID-19 vaccines.


Assuntos
COVID-19 , Glicoproteína da Espícula de Coronavírus , Animais , Cricetinae , Humanos , Vacinas contra COVID-19 , SARS-CoV-2 , Receptores Virais , Anticorpos Monoclonais , Anticorpos Antivirais , Anticorpos Neutralizantes
5.
Emerg Microbes Infect ; 12(2): 2245921, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37542391

RESUMO

Prevention of robust severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) infection in nasal turbinate (NT) requires in vivo evaluation of IgA neutralizing antibodies. Here, we report the efficacy of receptor binding domain (RBD)-specific monomeric B8-mIgA1 and B8-mIgA2, and dimeric B8-dIgA1, B8-dIgA2 and TH335-dIgA1 against intranasal SARS-CoV-2 challenge in Syrian hamsters. These antibodies exhibited comparable neutralization potency against authentic virus by competing with human angiotensin converting enzyme-2 (ACE2) receptor for RBD binding. While reducing viral loads in lungs significantly, prophylactic intranasal B8-dIgA unexpectedly led to high amount of infectious viruses and extended damage in NT compared to controls. Mechanistically, B8-dIgA failed to inhibit SARS-CoV-2 cell-to-cell transmission, but was hijacked by the virus through dendritic cell-mediated trans-infection of NT epithelia leading to robust nasal infection. Cryo-EM further revealed B8 as a class II antibody binding trimeric RBDs in 3-up or 2-up/1-down conformation. Neutralizing dIgA, therefore, may engage an unexpected mode of SARS-CoV-2 nasal infection and injury.


Assuntos
COVID-19 , Resfriado Comum , Cricetinae , Animais , Humanos , SARS-CoV-2 , Mesocricetus , Anticorpos Antivirais , Anticorpos Neutralizantes , Imunoglobulina A , Glicoproteína da Espícula de Coronavírus
6.
bioRxiv ; 2023 Apr 10.
Artigo em Inglês | MEDLINE | ID: mdl-37090592

RESUMO

SARS-CoV-2 continues to evolve and evade most existing neutralizing antibodies, including all clinically authorized antibodies. We have isolated and characterized two human monoclonal antibodies, 12-16 and 12-19, which exhibited neutralizing activities against all SARS-CoV-2 variants tested, including BQ.1.1 and XBB.1.5. They also blocked infection in hamsters challenged with Omicron BA.1 intranasally. Structural analyses revealed both antibodies targeted a conserved quaternary epitope located at the interface between the N-terminal domain and subdomain 1, revealing a previously unrecognized site of vulnerability on SARS-CoV-2 spike. These antibodies prevent viral receptor engagement by locking the receptor-binding domain of spike in the down conformation, revealing a novel mechanism of virus neutralization for non-RBD antibodies. Deep mutational scanning showed that SARS-CoV-2 could mutate to escape 12-19, but the responsible mutations are rarely found in circulating viruses. Antibodies 12-16 and 12-19 hold promise as prophylactic agents for immunocompromised persons who do not respond robustly to COVID-19 vaccines.

7.
Transp Res Rec ; 2677(4): 531-546, 2023 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38602901

RESUMO

COVID-19 has radically transformed urban travel behavior throughout the world. Agencies have had to provide adequate service while navigating a rapidly changing environment with reduced revenue. As COVID-19-related restrictions are lifted, transit agencies are concerned about their ability to adapt to changes in ridership behavior and public transit usage. To aid their becoming more adaptive to sudden or persistent shifts in ridership, we addressed three questions: To what degree has COVID-19 affected fixed-line public transit ridership and what is the relationship between reduced demand and -vehicle trips? How has COVID-19 changed ridership patterns and are they expected to persist after restrictions are lifted? Are there disparities in ridership changes across socioeconomic groups and mobility-impaired riders? Focusing on Nashville and Chattanooga, TN, ridership demand and vehicle trips were compared with anonymized mobile location data to study the relationship between mobility patterns and transit usage. Correlation analysis and multiple linear regression were used to investigate the relationship between socioeconomic indicators and changes in transit ridership, and an analysis of changes in paratransit demand before and during COVID-19. Ridership initially dropped by 66% and 65% over the first month of the pandemic for Nashville and Chattanooga, respectively. Cellular mobility patterns in Chattanooga indicated that foot traffic recovered to a greater degree than transit ridership between mid-April and the last week in June, 2020. Education-level had a statistically significant impact on changes in fixed-line bus transit, and the distribution of changes in demand for paratransit services were similar to those of fixed-line bus transit.

8.
Cell Rep Med ; 3(10): 100774, 2022 10 18.
Artigo em Inglês | MEDLINE | ID: mdl-36195094

RESUMO

"Pan-coronavirus" antivirals targeting conserved viral components can be designed. Here, we show that the rationally engineered H84T-banana lectin (H84T-BanLec), which specifically recognizes high mannose found on viral proteins but seldom on healthy human cells, potently inhibits Middle East respiratory syndrome coronavirus (MERS-CoV), severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) (including Omicron), and other human-pathogenic coronaviruses at nanomolar concentrations. H84T-BanLec protects against MERS-CoV and SARS-CoV-2 infection in vivo. Importantly, intranasally and intraperitoneally administered H84T-BanLec are comparably effective. Mechanistic assays show that H84T-BanLec targets virus entry. High-speed atomic force microscopy depicts real-time multimolecular associations of H84T-BanLec dimers with the SARS-CoV-2 spike trimer. Single-molecule force spectroscopy demonstrates binding of H84T-BanLec to multiple SARS-CoV-2 spike mannose sites with high affinity and that H84T-BanLec competes with SARS-CoV-2 spike for binding to cellular ACE2. Modeling experiments identify distinct high-mannose glycans in spike recognized by H84T-BanLec. The multiple H84T-BanLec binding sites on spike likely account for the drug compound's broad-spectrum antiviral activity and the lack of resistant mutants.


Assuntos
COVID-19 , Coronavírus da Síndrome Respiratória do Oriente Médio , Humanos , SARS-CoV-2 , Lectinas/farmacologia , Manose/farmacologia , Enzima de Conversão de Angiotensina 2 , Glicoproteína da Espícula de Coronavírus/farmacologia , Antivirais/farmacologia
9.
JHEP Rep ; 4(10): 100546, 2022 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-36052220

RESUMO

Background & Aims: HEV variants such as swine genotypes within Paslahepevirus species balayani (HEV-A) and rat HEV (Rocahepevirus ratti; HEV-C1) cause chronic hepatitis E in immunocompromised individuals. There are few reliable and accessible small animal models that accurately reflect chronic HEV infection. We aimed to develop an immunocompromised rat model of chronic hepatitis E infection. Methods: In this animal model infection study, rats were immunosuppressed with a drug combination (prednisolone, tacrolimus, and mycophenolate mofetil) commonly taken by transplant recipients. Rats were challenged with human- and rat-derived HEV-C1 strains or a human-derived HEV-A strain. Viral load, liver function, liver histology, humoural, and cellular immune responses were monitored. Results: A high-dose (HD) immunosuppressive regimen consistently prolonged human- and rat-derived HEV-C1 infection in rats (up to 12 weeks post infection) compared with transient infections in low-dose (LD) immunosuppressant-treated and immunocompetent (IC) rats. Mean HEV-C1 viral loads in stool, serum, and liver tissue were higher in HD regimen-treated rats than in LD or IC rats (p <0.05). Alanine aminotransferase elevation was observed in chronically infected rats, which was consistent with histological hepatitis and HEV-C1 antigen expression in liver tissue. None (0/6) of the HD regimen-treated, 5/6 LD regimen-treated, and 6/6 IC rats developed antibodies to HEV-C1 in species-specific immunoblots. Reversal of immunosuppression was associated with clearance of viraemia and restoration of HEV-C1-specific humoural and cellular immune responses in HD regimen-treated rats, mimicking patterns in treated patients with chronic hepatitis E. Viral load suppression was observed with i.p. ribavirin treatment. HD regimen-treated rats remained unsusceptible to HEV-A infection. Conclusions: We developed a scalable immunosuppressed rat model of chronic hepatitis E that closely mimics this infection phenotype in transplant recipients. Lay summary: Convenient small animal models are required for the study of chronic hepatitis E in humans. We developed an animal model of chronic hepatitis E by suppressing immune responses of rats with drugs commonly taken by humans as organ transplant rejection prophylaxis. This model closely mimicked features of chronic hepatitis E in humans.

10.
Nature ; 609(7928): 785-792, 2022 09.
Artigo em Inglês | MEDLINE | ID: mdl-35922005

RESUMO

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.


Assuntos
Ácido Aspártico , Caspase 6 , Infecções por Coronavirus , Coronavirus , Cisteína , Interações Hospedeiro-Patógeno , Replicação Viral , Animais , Apoptose , Ácido Aspártico/metabolismo , Caspase 6/metabolismo , Coronavirus/crescimento & desenvolvimento , Coronavirus/patogenicidade , Infecções por Coronavirus/enzimologia , Infecções por Coronavirus/virologia , Proteínas do Nucleocapsídeo de Coronavírus/imunologia , Proteínas do Nucleocapsídeo de Coronavírus/metabolismo , Cricetinae , Cisteína/metabolismo , Dipeptidil Peptidase 4/genética , Dipeptidil Peptidase 4/metabolismo , Humanos , Interferons/antagonistas & inibidores , Interferons/imunologia , Pulmão/patologia , Mesocricetus , Camundongos , Coronavírus da Síndrome Respiratória do Oriente Médio , Coronavírus Relacionado à Síndrome Respiratória Aguda Grave , SARS-CoV-2 , Taxa de Sobrevida , Redução de Peso
11.
J Pastoral Care Counsel ; 76(4): 304-306, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-35942727

RESUMO

Reflecting on his long career that integrated medicine, therapy, and Christian theology, the author shares his insight to help future students to have a simple framework of doing counseling, family therapy, and relating to the Christian faith. This article offers his personal views on how to do therapy, and proposes a way of looking at a Christian theory of personality, and towards a Christian theory of marriage and family therapy.


Assuntos
Terapia Familiar , Assistência Religiosa , Humanos , Teologia , Cristianismo/psicologia
12.
Emerg Microbes Infect ; 11(1): 2093-2101, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-35943779

RESUMO

The replication and pathogenicity of SARS-CoV-2 Omicron BA.2 are comparable to that of BA.1 in experimental animal models. However, BA.2 has rapidly emerged to overtake BA.1 to become the predominant circulating SARS-CoV-2 variant worldwide. Here, we compared the replication fitness of BA.1 and BA.2 in cell culture and in the Syrian hamster model of COVID-19. Using a reverse genetics approach, we found that the BA.1-specific spike mutation G496S compromises its replication fitness, which may contribute to BA.1 being outcompeted by BA.2 in the real world. Additionally, the BA.1-unique G496S substitution confers differentiated sensitivity to therapeutic monoclonal antibodies, which partially recapitulates the immunoevasive phenotype of BA.1 and BA.2. In summary, our study identified G496S as an important determinant during the evolutionary trajectory of SARS-CoV-2.


Assuntos
COVID-19 , SARS-CoV-2 , Animais , Anticorpos Monoclonais , Cricetinae , Humanos , Mesocricetus , Mutação de Sentido Incorreto , SARS-CoV-2/genética , Glicoproteína da Espícula de Coronavírus/genética
13.
Science ; 377(6604): 428-433, 2022 07 22.
Artigo em Inglês | MEDLINE | ID: mdl-35737809

RESUMO

The in vivo pathogenicity, transmissibility, and fitness of the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) Omicron (B.1.1.529) variant are not well understood. We compared these virological attributes of this new variant of concern (VOC) with those of the Delta (B.1.617.2) variant in a Syrian hamster model of COVID-19. Omicron-infected hamsters lost significantly less body weight and exhibited reduced clinical scores, respiratory tract viral burdens, cytokine and chemokine dysregulation, and lung damage than Delta-infected hamsters. Both variants were highly transmissible through contact transmission. In noncontact transmission studies Omicron demonstrated similar or higher transmissibility than Delta. Delta outcompeted Omicron without selection pressure, but this scenario changed once immune selection pressure with neutralizing antibodies-active against Delta but poorly active against Omicron-was introduced. Next-generation vaccines and antivirals effective against this new VOC are therefore urgently needed.


Assuntos
COVID-19 , SARS-CoV-2 , Animais , COVID-19/transmissão , Modelos Animais de Doenças , Mesocricetus , SARS-CoV-2/patogenicidade , Virulência
14.
Nat Commun ; 13(1): 3589, 2022 06 23.
Artigo em Inglês | MEDLINE | ID: mdl-35739114

RESUMO

The strikingly high transmissibility and antibody evasion of SARS-CoV-2 Omicron variants have posed great challenges to the efficacy of current vaccines and antibody immunotherapy. Here, we screen 34 BNT162b2-vaccinees and isolate a public broadly neutralizing antibody ZCB11 derived from the IGHV1-58 family. ZCB11 targets viral receptor-binding domain specifically and neutralizes all SARS-CoV-2 variants of concern, especially with great potency against authentic Omicron and Delta variants. Pseudovirus-based mapping of 57 naturally occurred spike mutations or deletions reveals that S371L results in 11-fold neutralization resistance, but it is rescued by compensating mutations in Omicron variants. Cryo-EM analysis demonstrates that ZCB11 heavy chain predominantly interacts with Omicron spike trimer with receptor-binding domain in up conformation blocking ACE2 binding. In addition, prophylactic or therapeutic ZCB11 administration protects lung infection against Omicron viral challenge in golden Syrian hamsters. These results suggest that vaccine-induced ZCB11 is a promising broadly neutralizing antibody for biomedical interventions against pandemic SARS-CoV-2.


Assuntos
Anticorpos Antivirais , Anticorpos Amplamente Neutralizantes , COVID-19 , Animais , Anticorpos Antivirais/imunologia , Vacina BNT162 , Anticorpos Amplamente Neutralizantes/imunologia , COVID-19/prevenção & controle , Cricetinae , Humanos , Mesocricetus , SARS-CoV-2/genética , Glicoproteína da Espícula de Coronavírus/genética
15.
Nat Commun ; 13(1): 2539, 2022 05 09.
Artigo em Inglês | MEDLINE | ID: mdl-35534483

RESUMO

Extrapulmonary complications of different organ systems have been increasingly recognized in patients with severe or chronic Coronavirus Disease 2019 (COVID-19). However, limited information on the skeletal complications of COVID-19 is known, even though inflammatory diseases of the respiratory tract have been known to perturb bone metabolism and cause pathological bone loss. In this study, we characterize the effects of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection on bone metabolism in an established golden Syrian hamster model for COVID-19. SARS-CoV-2 causes significant multifocal loss of bone trabeculae in the long bones and lumbar vertebrae of all infected hamsters. Moreover, we show that the bone loss is associated with SARS-CoV-2-induced cytokine dysregulation, as the circulating pro-inflammatory cytokines not only upregulate osteoclastic differentiation in bone tissues, but also trigger an amplified pro-inflammatory cascade in the skeletal tissues to augment their pro-osteoclastogenesis effect. Our findings suggest that pathological bone loss may be a neglected complication which warrants more extensive investigations during the long-term follow-up of COVID-19 patients. The benefits of potential prophylactic and therapeutic interventions against pathological bone loss should be further evaluated.


Assuntos
COVID-19 , Animais , COVID-19/complicações , Cricetinae , Modelos Animais de Doenças , Humanos , Mesocricetus , SARS-CoV-2
17.
Sci Transl Med ; 14(646): eabn6859, 2022 05 25.
Artigo em Inglês | MEDLINE | ID: mdl-35438546

RESUMO

The devastation caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has made clear the importance of pandemic preparedness. To address future zoonotic outbreaks due to related viruses in the sarbecovirus subgenus, we identified a human monoclonal antibody, 10-40, that neutralized or bound all sarbecoviruses tested in vitro and protected against SARS-CoV-2 and SARS-CoV in vivo. Comparative studies with other receptor-binding domain (RBD)-directed antibodies showed 10-40 to have the greatest breadth against sarbecoviruses, suggesting that 10-40 is a promising agent for pandemic preparedness. Moreover, structural analyses on 10-40 and similar antibodies not only defined an epitope cluster in the inner face of the RBD that is well conserved among sarbecoviruses but also uncovered a distinct antibody class with a common CDRH3 motif. Our analyses also suggested that elicitation of this class of antibodies may not be overly difficult, an observation that bodes well for the development of a pan-sarbecovirus vaccine.


Assuntos
COVID-19 , SARS-CoV-2 , Anticorpos Antivirais , Humanos , Isotipos de Imunoglobulinas , Glicoproteína da Espícula de Coronavírus
18.
Clin Infect Dis ; 75(1): e76-e81, 2022 08 24.
Artigo em Inglês | MEDLINE | ID: mdl-35234870

RESUMO

BACKGROUND: Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) can infect human and other mammals, including hamsters. Syrian (Mesocricetus auratus) and dwarf (Phodopus sp.) hamsters are susceptible to SARS-CoV-2 infection in the laboratory setting. However, pet shop-related Coronavirus Disease 2019 (COVID-19) outbreaks have not been reported. METHODS: We conducted an investigation of a pet shop-related COVID-19 outbreak due to Delta variant AY.127 involving at least 3 patients in Hong Kong. We tested samples collected from the patients, environment, and hamsters linked to this outbreak and performed whole genome sequencing analysis of the reverse transcription polymerase chain reaction (RT-PCR)-positive samples. RESULTS: The patients included a pet shop keeper (Patient 1), a female customer of the pet shop (Patient 2), and the husband of Patient 2 (Patient 3). Investigation showed that 17.2% (5/29) and 25.5% (13/51) environmental specimens collected from the pet shop and its related warehouse, respectively, tested positive for SARS-CoV-2 RNA by RT-PCR. Among euthanized hamsters randomly collected from the storehouse, 3% (3/100) tested positive for SARS-CoV-2 RNA by RT-PCR and seropositive for anti-SARS-CoV-2 antibody by enzyme immunoassay. Whole genome analysis showed that although all genomes from the outbreak belonged to the Delta variant AY.127, there were at least 3 nucleotide differences among the genomes from different patients and the hamster cages. Genomic analysis suggests that multiple strains have emerged within the hamster population, and these different strains have likely transmitted to human either via direct contact or via the environment. CONCLUSIONS: Our study demonstrated probable hamster-to-human transmission of SARS-CoV-2. As pet trading is common around the world, this can represent a route of international spread of this pandemic virus.


Assuntos
COVID-19 , SARS-CoV-2 , Animais , Cricetinae , Surtos de Doenças , Feminino , Hong Kong/epidemiologia , Humanos , Mamíferos , RNA Viral/genética , SARS-CoV-2/genética
19.
Clin Infect Dis ; 75(1): e1101-e1111, 2022 08 24.
Artigo em Inglês | MEDLINE | ID: mdl-34536277

RESUMO

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.


Assuntos
COVID-19 , Actinas , Animais , Anticorpos Neutralizantes , Cricetinae , Modelos Animais de Doenças , Humanos , Pulmão , Mesocricetus , SARS-CoV-2 , Temperatura
20.
EMBO Mol Med ; 14(1): e14485, 2022 01 11.
Artigo em Inglês | MEDLINE | ID: mdl-34826211

RESUMO

SPINK6 was identified in human skin as a cellular inhibitor of serine proteases of the KLK family. Airway serine proteases are required to cleave hemagglutinin (HA) of influenza A viruses (IAVs) to initiate an infection in the human airway. We hypothesized that SPINK6 may inhibit common airway serine proteases and restrict IAV activation. We demonstrate that SPINK6 specifically suppresses the proteolytic activity of HAT and KLK5, HAT- and KLK5-mediated HA cleavage, and restricts virus maturation and replication. SPINK6 constrains the activation of progeny virions and impairs viral growth; and vice versa, blocking endogenous SPINK6 enhances HA cleavage and viral growth in physiological-relevant human airway organoids where SPINK6 is intrinsically expressed. In IAV-infected mice, SPINK6 significantly suppresses viral growth and improves mouse survival. Notably, individuals carrying the higher SPINK6 expression allele were protected from human H7N9 infection. Collectively, SPINK6 is a novel host inhibitor of serine proteases in the human airway and restricts IAV activation.


Assuntos
Subtipo H7N9 do Vírus da Influenza A , Influenza Humana , Inibidores de Serinopeptidase do Tipo Kazal/metabolismo , Ativação Viral , Animais , Glicoproteínas de Hemaglutininação de Vírus da Influenza/metabolismo , Humanos , Subtipo H7N9 do Vírus da Influenza A/fisiologia , Camundongos , Serina Proteases/metabolismo
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