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1.
Risk Anal ; 2024 Aug 23.
Artículo en Inglés | MEDLINE | ID: mdl-39175371

RESUMEN

Realizing positive social and environmental outcomes from assisted ecosystem adaptation requires the management of complex, uncertain, and ambiguous risks. Using assisted coral reef adaptation as a case study, this article presents a conceptual framework that defines social impacts as the physical and cognitive consequences for people of planned intervention and social risks as potential impacts transformed into objects of management through assessment and governance. Reflecting on its multiple uses in the literature, we consider "social risk" in relation to risks to individuals and communities, risks to First Peoples, risks to businesses or project implementation, possibilities for amplified social vulnerability, and risk perceptions. Although much of this article is devoted to bringing clarity to the different ways in which social risk manifests and to the multiple characters of risk and uncertainty, it is apparent that risk governance itself must be an inherently integrative and social process.

2.
Virus Res ; 346: 199409, 2024 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-38815869

RESUMEN

Crimean-Congo Haemorrhagic Fever Virus (CCHFV) is spread by infected ticks or direct contact with blood, tissues and fluids from infected patients or livestock. Infection with CCHFV causes severe haemorrhagic fever in humans which is fatal in up to 83 % of cases. CCHFV is listed as a priority pathogen by the World Health Organization (WHO) and there are currently no widely-approved vaccines. Defining a serological correlate of protection against CCHFV infection would support the development of vaccines by providing a 'target threshold' for pre-clinical and clinical immunogenicity studies to achieve in subjects and potentially obviate the need for in vivo protection studies. We therefore sought to establish titratable protection against CCHFV using pooled human convalescent plasma, in a mouse model. Convalescent plasma collected from seven individuals with a known previous CCHFV virus infection were characterised using binding antibody and neutralisation assays. All plasma recognised nucleoprotein and the Gc glycoprotein, but some had a lower Gn glycoprotein response by ELISA. Pooled plasma and two individual donations from convalescent donors were administered intraperitoneally to A129 mice 24 h prior to intradermal challenge with CCHFV (strain IbAr10200). A partial protective effect was observed with all three convalescent plasmas characterised by longer survival post-challenge and reduced clinical score. These protective responses were titratable. Further characterisation of the serological reactivities within these samples will establish their value as reference materials to support assay harmonisation and accelerate vaccine development for CCHFV.


Asunto(s)
Anticuerpos Neutralizantes , Anticuerpos Antivirales , Modelos Animales de Enfermedad , Virus de la Fiebre Hemorrágica de Crimea-Congo , Fiebre Hemorrágica de Crimea , Animales , Fiebre Hemorrágica de Crimea/inmunología , Fiebre Hemorrágica de Crimea/prevención & control , Ratones , Virus de la Fiebre Hemorrágica de Crimea-Congo/inmunología , Anticuerpos Antivirales/sangre , Anticuerpos Antivirales/inmunología , Humanos , Anticuerpos Neutralizantes/sangre , Anticuerpos Neutralizantes/inmunología , Femenino , Pruebas de Neutralización , Plasma/inmunología , Masculino
3.
Viruses ; 15(12)2023 11 30.
Artículo en Inglés | MEDLINE | ID: mdl-38140610

RESUMEN

Rift Valley fever virus (RVFV) is a mosquito-borne zoonotic pathogen causing disease in livestock and humans. Whilst initially restricted to the African continent, recent spread to the Arabian Peninsula has highlighted the likelihood of entry into new regions. Due to the absence of a regulatory-approved human vaccine, work is ongoing to develop and assess countermeasures. As such, small animal models play a pivotal role in providing information on disease pathogenesis and elucidating which intervention strategies confer protection. To develop and establish the BALB/c mouse model, we challenged mice with RVFV grown from two separate cell lines: one derived from mosquitoes (C6/36) and the other mammalian derived (Vero E6). Following infection, we assessed the clinical course of disease progression at days 1 and 3 post-challenge and evaluated viral tropism and immune analytes. The results demonstrated that RVFV infection was affected by the cell line used to propagate the challenge virus, with those grown in insect cells resulting in a more rapid disease progression. The lowest dose that caused uniform severe disease remained the same across both virus preparations. In addition, to demonstrate reproducibility, the lowest dose was used for a subsequent infection study using male and female animals. The results further demonstrated that male mice succumbed to infection more rapidly than their female counterparts. Our results establish an RVFV mouse model and key parameters that affect the course of disease progression in BALB/c mice.


Asunto(s)
Fiebre del Valle del Rift , Virus de la Fiebre del Valle del Rift , Masculino , Femenino , Humanos , Animales , Ratones , Ratones Endogámicos BALB C , Reproducibilidad de los Resultados , Progresión de la Enfermedad , Mamíferos
5.
Sci Rep ; 13(1): 13912, 2023 08 25.
Artículo en Inglés | MEDLINE | ID: mdl-37626085

RESUMEN

The development of new therapies against SARS-CoV-2 is required to extend the toolkit of intervention strategies to combat the global pandemic. In this study, hyperimmune plasma from sheep immunised with whole spike SARS-CoV-2 recombinant protein has been used to generate candidate products. In addition to purified IgG, we have refined candidate therapies by removing non-specific IgG via affinity binding along with fragmentation to eliminate the Fc region to create F(ab')2 fragments. These preparations were evaluated for in vitro activity and demonstrated to be strongly neutralising against a range of SARS-CoV-2 strains, including Omicron B2.2. In addition, their protection against disease manifestations and viral loads were assessed using a hamster SARS-CoV-2 infection model. Results demonstrated protective effects of both IgG and F(ab')2, with the latter requiring sequential dosing to maintain in vivo activity due to rapid clearance from the circulation.


Asunto(s)
COVID-19 , SARS-CoV-2 , Cricetinae , Animales , Ovinos , Inmunización Pasiva , Cinética , Inmunoglobulina G
6.
Pathogens ; 12(8)2023 Jul 26.
Artículo en Inglés | MEDLINE | ID: mdl-37623936

RESUMEN

Nipah virus (NiV) is an emerging pathogen that can cause severe respiratory illness and encephalitis in humans. The main reservoir is fruit bats, distributed across a large geographical area that includes Australia, Southeast Asia, and Africa. Incursion into humans is widely reported through exposure of infected pigs, ingestion of contaminated food, or through contact with an infected person. With no approved treatments or vaccines, NiV poses a threat to human public health and has epidemic potential. To aid with the assessment of emerging interventions being developed, an expansion of preclinical testing capability is required. Given variations in the model parameters observed in different sites during establishment, optimisation of challenge routes and doses is required. Upon evaluating the hamster model, an intranasal route of challenge was compared with intraperitoneal delivery, demonstrating a more rapid dissemination to wider tissues in the latter. A dose effect was observed between those causing respiratory illness and those resulting in neurological disease. The data demonstrate the successful establishment of the hamster model of NiV disease for subsequent use in the evaluation of vaccines and antivirals.

7.
bioRxiv ; 2023 May 03.
Artículo en Inglés | MEDLINE | ID: mdl-37205552

RESUMEN

Cardiomyocytes in the sinoatrial node (SAN) are specialized to undergo spontaneous diastolic depolarization (DD) to create action potentials (AP) that serve as the origin of the heartbeat. Two cellular clocks govern DD: the membrane clock where ion channels contribute ionic conductance to create DD and the Ca 2+ clock where rhythmic Ca 2+ release from sarcoplasmic reticulum (SR) during diastole contributes pacemaking. How the membrane and Ca 2+ clocks interact to synchronize and drive DD is not well understood. Here, we identified stromal interaction molecule 1 (STIM1), the activator of store operated Ca 2+ entry (SOCE), in the P-cell cardiomyocytes of the SAN. Functional studies from STIM1 KO mice reveal dramatic changes in properties of AP and DD. Mechanistically, we show that STIM1 regulates the funny currents and HCN4 channels that are required to initiate DD and maintain sinus rhythm in mice. Taken together, our studies suggest that STIM1 acts as a sensor for both the Ca 2+ and membrane clocks for mouse SAN for cardiac pacemaking.

8.
Viruses ; 15(3)2023 03 11.
Artículo en Inglés | MEDLINE | ID: mdl-36992434

RESUMEN

The emergence of severe acute respiratory syndrome coronavirus (SARS-CoV-2) and its expansion to a worldwide pandemic resulted in efforts to assess and develop interventions to reduce the disease burden. Despite the introduction of vaccine programmes against SARS-CoV-2, global incidence levels in early 2022 remained high, demonstrating a need for the development of physiologically relevant models, which are essential for the identification of alternative antiviral strategies. The hamster model of SARS-CoV-2 infection has been widely adopted due to similarities with humans in terms of host cell entry mechanism (via ACE2), and aspects of symptomology and virus shedding. We have previously described a natural transmission hamster model that better represents the natural course of infection. In the present study, we have conducted further testing of the model using the first-in-class antiviral Neumifil, which has previously shown promise against SARS-CoV-2 after a direct intranasal challenge. Neumifil is an intranasally delivered carbohydrate-binding module (CBM) which reduces the binding of viruses to their cellular receptor. By targeting the host cell, Neumifil has the potential to provide broad protection against multiple pathogens and variants. This study demonstrates that using a combination of a prophylactic and therapeutic delivery of Neumifil significantly reduces the severity of clinical signs in animals infected via a natural route of transmission and indicates a reduction of viral loads in the upper respiratory tract. Further refinements of the model are required in order to ensure the adequate transmission of the virus. However, our results provide additional data to the evidence base of Neumifil efficacy against respiratory virus infection and demonstrate that the transmission model is a potentially valuable tool for testing antiviral compounds against SARS-CoV-2.


Asunto(s)
COVID-19 , SARS-CoV-2 , Animales , Cricetinae , Humanos , SARS-CoV-2/metabolismo , Antivirales/farmacología , Antivirales/uso terapéutico , Antivirales/química , Carbohidratos
9.
Pathogens ; 12(3)2023 Mar 01.
Artículo en Inglés | MEDLINE | ID: mdl-36986321

RESUMEN

Crimean-Congo haemorrhagic fever virus (CCHFV) is a pathogen of increasing public health concern, being a widely distributed arbovirus and the causative agent of the potentially fatal Crimean-Congo haemorrhagic fever. Hazara virus (HAZV) is a genetically and serologically related virus that has been proposed as a surrogate for antiviral and vaccine testing for CCHFV. Glycosylation analysis of HAZV has been limited; first, we confirmed for the first time the occupation of two N-glycosylation sites in the HAZV glycoprotein. Despite this, there was no apparent antiviral efficacy of a panel of iminosugars against HAZV, as determined by quantification of the total secretion and infectious virus titres produced following infection of SW13 and Vero cells. This lack of efficacy was not due to an inability of deoxynojirimycin (DNJ)-derivative iminosugars to access and inhibit endoplasmic reticulum α-glucosidases, as demonstrated by free oligosaccharide analysis in uninfected and infected SW13 and uninfected Vero cells. Even so, iminosugars may yet have potential as antivirals for CCHFV since the positions and importance of N-linked glycans may differ between the viruses, a hypothesis requiring further evaluation.

10.
EBioMedicine ; 90: 104523, 2023 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-36933409

RESUMEN

BACKGROUND: The tick-borne bunyavirus, Crimean-Congo Haemorrhagic Fever virus (CCHFV), can cause severe febrile illness in humans and has a wide geographic range that continues to expand due to tick migration. Currently, there are no licensed vaccines against CCHFV for widespread usage. METHODS: In this study, we describe the preclinical assessment of a chimpanzee adenoviral vectored vaccine (ChAdOx2 CCHF) which encodes the glycoprotein precursor (GPC) from CCHFV. FINDINGS: We demonstrate here that vaccination with ChAdOx2 CCHF induces both a humoral and cellular immune response in mice and 100% protection in a lethal CCHF challenge model. Delivery of the adenoviral vaccine in a heterologous vaccine regimen with a Modified Vaccinia Ankara vaccine (MVA CCHF) induces the highest levels of CCHFV-specific cell-mediated and antibody responses in mice. Histopathological examination and viral load analysis of the tissues of ChAdOx2 CCHF immunised mice reveals an absence of both microscopic changes and viral antigen associated with CCHF infection, further demonstrating protection against disease. INTERPRETATION: There is the continued need for an effective vaccine against CCHFV to protect humans from lethal haemorrhagic disease. Our findings support further development of the ChAd platform expressing the CCHFV GPC to seek an effective vaccine against CCHFV. FUNDING: This research was supported by funding from the Biotechnology and Biological Sciences Research Council (UKRI-BBSRC) [BB/R019991/1 and BB/T008784/1].


Asunto(s)
Virus de la Fiebre Hemorrágica de Crimea-Congo , Fiebre Hemorrágica de Crimea , Vacunas Virales , Humanos , Animales , Ratones , Fiebre Hemorrágica de Crimea/prevención & control , Virus de la Fiebre Hemorrágica de Crimea-Congo/genética , Vacunación , Vectores Genéticos/genética , Virus Vaccinia
11.
J Immunol Methods ; 512: 113405, 2023 01.
Artículo en Inglés | MEDLINE | ID: mdl-36496007

RESUMEN

Humanised antibodies targeting Crimean-Congo Haemorrhagic virus (CCHFV) are needed for the development and standardisation of serological assays. These assays are needed to address a shortfall in available tests that meet regulatory diagnostic standards and to aid surveillance activities to extend knowledge on the distribution of CCHFV. To generate a humanised monoclonal antibody against CCHFV, we have compared two methods: the traditional mouse hybridoma approach with subsequent sequencing and humanisation of antibodies versus a non-animal alternative using a human combinatorial antibody library (HuCAL). Our results demonstrated that the mouse hybridoma followed by humanisation protocol gave higher affinity antibodies. Whilst not yet able to demonstrate the generation of equivalent humanised antibodies without the use of animals, sequencing data enables the subsequent production of recombinant antibodies, thus providing a reduction in future animal usage for this application. Ultimately, our report provides information on development of a humanised standardised control, which can form an important positive control component of serological assays against CCHFV.


Asunto(s)
Virus de la Fiebre Hemorrágica de Crimea-Congo , Fiebre Hemorrágica de Crimea , Humanos , Animales , Ratones , Fiebre Hemorrágica de Crimea/diagnóstico , Fiebre Hemorrágica de Crimea/epidemiología , Hibridomas , Anticuerpos Antivirales , Inmunoglobulina G
12.
Antiviral Res ; 203: 105332, 2022 07.
Artículo en Inglés | MEDLINE | ID: mdl-35533779

RESUMEN

Antibodies against SARS-CoV-2 are important to generate protective immunity, with convalescent plasma one of the first therapies approved. An alternative source of polyclonal antibodies suitable for upscaling would be more amendable to regulatory approval and widespread use. In this study, sheep were immunised with SARS-CoV-2 whole spike protein or one of the subunit proteins: S1 and S2. Once substantial antibody titres were generated, plasma was collected and samples pooled for each antigen. Non-specific antibodies were removed via affinity-purification to yield candidate products for testing in a hamster model of SARS-CoV-2 infection. Affinity-purified polyclonal antibodies to whole spike, S1 and S2 proteins were evaluated for in vitro for neutralising activity against SARS-CoV-2 Wuhan-like virus (Australia/VIC01/2020) and a recent variant of concern, B.1.1.529 BA.1 (Omicron), antibody-binding, complement fixation and phagocytosis assays were also performed. All antibody preparations demonstrated an effect against SARS-CoV-2 disease in the hamster model of challenge, with those raised against the S2 subunit providing the most promise. A rapid, cost-effective therapy for COVID-19 was developed which provides a source of highly active immunoglobulin specific to SARS-CoV-2 with multi-functional activity.


Asunto(s)
Tratamiento Farmacológico de COVID-19 , COVID-19 , Animales , Anticuerpos Neutralizantes/uso terapéutico , Anticuerpos Antivirales , COVID-19/terapia , Análisis Costo-Beneficio , Inmunización Pasiva , SARS-CoV-2 , Ovinos , Glicoproteína de la Espiga del Coronavirus , Sueroterapia para COVID-19
13.
J Infect Dis ; 225(8): 1367-1376, 2022 04 19.
Artículo en Inglés | MEDLINE | ID: mdl-32880628

RESUMEN

BACKGROUND: The largest West African monkeypox outbreak began September 2017, in Nigeria. Four individuals traveling from Nigeria to the United Kingdom (n = 2), Israel (n = 1), and Singapore (n = 1) became the first human monkeypox cases exported from Africa, and a related nosocomial transmission event in the United Kingdom became the first confirmed human-to-human monkeypox transmission event outside of Africa. METHODS: Epidemiological and molecular data for exported and Nigerian cases were analyzed jointly to better understand the exportations in the temporal and geographic context of the outbreak. RESULTS: Isolates from all travelers and a Bayelsa case shared a most recent common ancestor and traveled to Bayelsa, Delta, or Rivers states. Genetic variation for this cluster was lower than would be expected from a random sampling of genomes from this outbreak, but data did not support direct links between travelers. CONCLUSIONS: Monophyly of exportation cases and the Bayelsa sample, along with the intermediate levels of genetic variation, suggest a small pool of related isolates is the likely source for the exported infections. This may be the result of the level of genetic variation present in monkeypox isolates circulating within the contiguous region of Bayelsa, Delta, and Rivers states, or another more restricted, yet unidentified source pool.


Asunto(s)
Monkeypox virus , Mpox , Brotes de Enfermedades , Humanos , Mpox/epidemiología , Monkeypox virus/genética , Nigeria/epidemiología , Reino Unido
14.
Sci Rep ; 11(1): 23760, 2021 12 09.
Artículo en Inglés | MEDLINE | ID: mdl-34887488

RESUMEN

Protected areas aim to conserve nature, ecosystem services, and cultural values; however, they have variable success in doing so under high development pressure. Southeast Asian protected areas faced the highest level of human pressure at the turn of the twenty-first century. To estimate their effectiveness in conserving forest cover and forest carbon stocks for 2000-2018, we used statistical matching methods to control for the non-random location of protected areas, to compare protection against a matched counterfactual. We found Southeast Asian protected areas had three times less forest cover loss than similar landscapes without protection. Protected areas that had completed management reporting using the Management Effectiveness Tracking Tool (METT) conserved significantly more forest cover and forest carbon stocks than those that had not. Management scores were positively associated with the level of carbon emissions avoided, but not the level of forest cover loss avoided. Our study is the first to find that METT scores could predict the level of carbon emissions avoided in protected areas. Given that only 11% of protected areas in Southeast Asia had completed METT surveys, our results illustrate the need to scale-up protected area management effectiveness reporting programs to improve their effectiveness for conserving forests, and for storing and sequestering carbon.

15.
Viruses ; 13(11)2021 11 09.
Artículo en Inglés | MEDLINE | ID: mdl-34835057

RESUMEN

The global pandemic of coronavirus disease (COVID-19) caused by infection with severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) has led to an international thrust to study pathogenesis and evaluate interventions. Experimental infection of hamsters and the resulting respiratory disease is one of the preferred animal models since clinical signs of disease and virus shedding are similar to more severe cases of human COVID-19. The main route of challenge has been direct inoculation of the virus via the intranasal route. To resemble the natural infection, we designed a bespoke natural transmission cage system to assess whether recipient animals housed in physically separate adjacent cages could become infected from a challenged donor animal in a central cage, with equal airflow across the two side cages. To optimise viral shedding in the donor animals, a low and moderate challenge dose were compared after direct intranasal challenge, but similar viral shedding responses were observed and no discernible difference in kinetics. The results from our natural transmission set-up demonstrate that most recipient hamsters are infected within the system developed, with variation in the kinetics and levels of disease between individual animals. Common clinical outputs used for the assessment in directly-challenged hamsters, such as weight loss, are less obvious in hamsters who become infected from naturally acquiring the infection. The results demonstrate the utility of a natural transmission model for further work on assessing the differences between virus strains and evaluating interventions using a challenge system which more closely resembles human infection.


Asunto(s)
COVID-19/transmisión , Modelos Animales de Enfermedad , Mesocricetus , SARS-CoV-2/fisiología , Animales , COVID-19/patología , COVID-19/virología , Cricetinae , Femenino , Pulmón/patología , Masculino , Cavidad Nasal/patología , Carga Viral , Esparcimiento de Virus
16.
Glob Chang Biol ; 27(19): 4935-4945, 2021 10.
Artículo en Inglés | MEDLINE | ID: mdl-34170593

RESUMEN

Addressing climate change risks requires collaboration and engagement across all sectors of society. In particular, effective partnerships are needed between research scientists producing new knowledge, policy-makers and practitioners who apply conservation actions on the ground. We describe the implementation of a model for increasing the application and useability of biodiversity research in climate adaptation policy and practice. The focus of the program was to increase the ability of a state government agency and natural resource practitioners in Australia to manage and protect biodiversity in a changing climate. The model comprised a five-stage process for enhancing impact (i) initiation of research projects that addressed priority conservation policy and management issues; (ii) co-design of the research using a collaborative approach involving multiple stakeholders; (iii) implementation of the research and design of decision tools and web-based resources; (iv) collaborative dissemination of the tools and resources via government and community working groups; and (v) evaluation of research impact. We report on the model development and implementation, and critically reflect on the model's impact. We share the lessons learnt from the challenges of operating within a stakeholder group with diverse objectives and criteria for success, and provide a template for creating an environmental research program with real world impact.


Asunto(s)
Biodiversidad , Recursos Naturales , Cambio Climático , Conservación de los Recursos Naturales , Políticas
17.
J Osteopath Med ; 121(1): 71-83, 2021 Jan 01.
Artículo en Inglés | MEDLINE | ID: mdl-33125033

RESUMEN

CONTEXT: There is a paucity of research assessing the efficacy of osteopathic manipulative treatment (OMT) in patients with vertigo. OBJECTIVE: To assess the feasibility of conducting a randomized, controlled trial comparing OMT and vestibular rehabilitation therapy (VRT), alone or in combination, in patients with vertigo and somatic dysfunction. METHODS: Volunteers with vertigo who were also diagnosed with somatic dysfunction (SD) were prospectively enrolled in a blinded, randomized, controlled cohort comparative effectiveness study and assigned to 1 of 4 groups: OMT alone, VRT alone, a combination of OMT and VRT (OMT/VRT), or a nonintervention control group. Participants between 18 and 79 years of age were included if they had experienced symptoms of vertigo for at least 3 months' duration, demonstrated somatic dysfunction, and could participate in computerized dynamic posturography (CDP) testing, tolerate manual therapy and exercises, and communicate effectively in English or Spanish. A total of 3 treatments lasting 45 minutes each were administered 1 week apart to each participant. OMT in this study consisted of counterstrain, myofascial release, balanced ligamentous tension, soft tissue, HVLA, and articulatory techniques. Comparisons were made between composite scores (CS) assessed with computerized dynamic posturography (CDP), dizziness handicap inventory (DHI), optometric evaluation, and osteopathic structural examinations collected before the first treatment, after the third/final treatment, and 3 months after the final treatment. (ClinicalTrials.gov number NCT01529151). RESULTS: A total of 23 patients were included in the study: 7 in the OMT group, 5 in the VRT group, 6 in the OMT/VRT group, and 5 in the control group. The OMT/VRT group demonstrated significant improvement in DHI score (P=0.0284) and CS (P=0.0475) between pre- and 3-month posttreatment measures. For total severity, improvements were significant in the OMT group both from pretreatment to immediate posttreatment measures (P=0.0114) and from pretreatment to 3-month posttreatment measures (P=0.0233). There was a statistical difference between the OMT and control groups from pretreatment to 3-month posttreatment DHI scores (P=0.0332). Also, there was a statistical difference in DHI score between VRT and control from pre- to 3-month posttreatment scores (P=0.0338). OMT/VRT statistically and clinically improved visual acuity in patients' right eyes from pre- to posttreatment (P=0.0325). In all participants, vergence dysfunction was prevalent (5; 21.7%) in addition to vertical heterophoria (15; 65.2%). CONCLUSION: A combination of OMT and VRT significantly reduced vertigo and improved balance 3 months after treatment (P<0.05). There was a high prevalence in vergence and vertical heterophoria, which are not typical screening measurements used by physical therapists and physicians to assess vertigo patients. With a small sample size, this study demonstrated the feasibility of an interdisciplinary team evaluating and treating patients with vertigo in a community setting. A larger study is needed to assess the efficacy of OMT/VRT in vertigo patients.


Asunto(s)
Osteopatía , Vértigo , Adolescente , Adulto , Anciano , Mareo , Terapia por Ejercicio , Estudios de Factibilidad , Humanos , Persona de Mediana Edad , Adulto Joven
18.
Sci Rep ; 10(1): 21431, 2020 12 08.
Artículo en Inglés | MEDLINE | ID: mdl-33293534

RESUMEN

In the event of an unpredictable viral outbreak requiring high/maximum biosafety containment facilities (i.e. BSL3 and BSL4), X-ray irradiation has the potential to relieve pressures on conventional diagnostic bottlenecks and expediate work at lower containment. Guided by Monte Carlo modelling and in vitro 1-log10 decimal-reduction value (D-value) predictions, the X-ray photon energies required for the effective inactivation of zoonotic viruses belonging to the medically important families of Flaviviridae, Nairoviridae, Phenuiviridae and Togaviridae are demonstrated. Specifically, it is shown that an optimized irradiation approach is attractive for use in a multitude of downstream detection and functional assays, as it preserves key biochemical and immunological properties. This study provides evidence that X-ray irradiation can support emergency preparedness, outbreak response and front-line diagnostics in a safe, reproducible and scalable manner pertinent to operations that are otherwise restricted to higher containment BSL3 or BSL4 laboratories.


Asunto(s)
Virus ARN/fisiología , ARN Viral/genética , Inactivación de Virus , Rayos X/efectos adversos , Animales , Chlorocebus aethiops , Defensa Civil , Contención de Riesgos Biológicos , Células Nutrientes , Humanos , Método de Montecarlo , Nairovirus/fisiología , Nairovirus/efectos de la radiación , Virus ARN/efectos de la radiación , ARN Viral/efectos de la radiación , Análisis de Secuencia de ARN , Togaviridae/fisiología , Togaviridae/efectos de la radiación , Células Vero , Zoonosis Virales/prevención & control , Virus Zika/fisiología , Virus Zika/efectos de la radiación
19.
J Gen Virol ; 101(10): 1047-1055, 2020 10.
Artículo en Inglés | MEDLINE | ID: mdl-32667279

RESUMEN

Type I interferon receptor knockout mice (strain A129) were assessed as a disease model of hantavirus infection. A range of infection routes (intramuscular, intraperitoneal and intranasal) were assessed using minimally passaged Seoul virus (strain Humber). Dissemination of virus to the spleen, kidney and lung was observed at 5 days after intramuscular and intraperitoneal challenge, which was resolved by day 14. In contrast, intranasal challenge of A129 mice demonstrated virus tropism to the lung, which was maintained to day 14 post-challenge. These data support the use of the A129 mouse model for future infection studies and the in vivo evaluation of interventions.


Asunto(s)
Modelos Animales de Enfermedad , Infecciones por Hantavirus , Orthohantavirus/fisiología , Animales , Orthohantavirus/aislamiento & purificación , Orthohantavirus/patogenicidad , Infecciones por Hantavirus/patología , Infecciones por Hantavirus/virología , Fiebre Hemorrágica con Síndrome Renal/patología , Fiebre Hemorrágica con Síndrome Renal/virología , Riñón/virología , Hígado/patología , Pulmón/patología , Pulmón/virología , Masculino , Ratones , Ratones Noqueados , ARN Viral/análisis , ARN Viral/sangre , Receptor de Interferón alfa y beta/genética , Bazo/patología , Bazo/virología , Tropismo Viral
20.
Vaccines (Basel) ; 8(2)2020 Jun 16.
Artículo en Inglés | MEDLINE | ID: mdl-32560145

RESUMEN

The flavivirus envelope protein domain III (EDIII) was an effective immunogen against dengue virus (DENV) and other related flaviviruses. Whether this can be applied to the Zika virus (ZIKV) vaccinology remains an open question. Here, we tested the efficacy of ZIKV-EDIII against ZIKV infection, using several vaccine platforms that present the antigen in various ways. We provide data demonstrating that mice vaccinated with a ZIKV-EDIII as DNA or protein-based vaccines failed to raise fully neutralizing antibodies and did not control viremia, following a ZIKV challenge, despite eliciting robust antibody responses. Furthermore, we showed that ZIKV-EDIII encoded in replication-deficient Chimpanzee adenovirus (ChAdOx1-EDIII) elicited anti-ZIKV envelope antibodies in vaccinated mice but also provided limited protection against ZIKV in two physiologically different mouse challenge models. Taken together, our data indicate that contrary to what was shown for other flaviviruses like the dengue virus, which has close similarities with ZIKV-EDIII, this antigen might not be a suitable vaccine candidate for the correct induction of protective immune responses against ZIKV.

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