RESUMO
Several ebolaviruses cause outbreaks of severe disease. Vaccines and monoclonal antibody cocktails are available to treat Ebola virus (EBOV) infections, but not Sudan virus (SUDV) or other ebolaviruses. Current cocktails contain antibodies that cross-react with the secreted soluble glycoprotein (sGP) that absorbs virus-neutralizing antibodies. By sorting memory B cells from EBOV infection survivors, we isolated two broadly reactive anti-GP monoclonal antibodies, 1C3 and 1C11, that potently neutralize, protect rodents from disease, and lack sGP cross-reactivity. Both antibodies recognize quaternary epitopes in trimeric ebolavirus GP. 1C11 bridges adjacent protomers via the fusion loop. 1C3 has a tripartite epitope in the center of the trimer apex. One 1C3 antigen-binding fragment anchors simultaneously to the three receptor-binding sites in the GP trimer, and separate 1C3 paratope regions interact differently with identical residues on the three protomers. A cocktail of both antibodies completely protected nonhuman primates from EBOV and SUDV infections, indicating their potential clinical value.
Assuntos
Anticorpos Neutralizantes , Anticorpos Antivirais , Ebolavirus , Doença pelo Vírus Ebola , Animais , Epitopos , Glicoproteínas/química , Subunidades ProteicasRESUMO
Ebolaviruses cause a severe and often fatal illness with the potential for global spread. Monoclonal antibody-based treatments that have become available recently have a narrow therapeutic spectrum and are ineffective against ebolaviruses other than Ebola virus (EBOV), including medically important Bundibugyo (BDBV) and Sudan (SUDV) viruses. Here, we report the development of a therapeutic cocktail comprising two broadly neutralizing human antibodies, rEBOV-515 and rEBOV-442, that recognize non-overlapping sites on the ebolavirus glycoprotein (GP). Antibodies in the cocktail exhibited synergistic neutralizing activity, resisted viral escape, and possessed differing requirements for their Fc-regions for optimal in vivo activities. The cocktail protected non-human primates from ebolavirus disease caused by EBOV, BDBV, or SUDV with high therapeutic effectiveness. High-resolution structures of the cocktail antibodies in complex with GP revealed the molecular determinants for neutralization breadth and potency. This study provides advanced preclinical data to support clinical development of this cocktail for pan-ebolavirus therapy.
Assuntos
Anticorpos Antivirais/imunologia , Ebolavirus/imunologia , Doença pelo Vírus Ebola/imunologia , Doença pelo Vírus Ebola/prevenção & controle , Sequência de Aminoácidos , Animais , Anticorpos Monoclonais/imunologia , Anticorpos Neutralizantes/imunologia , Sítios de Ligação , Linhagem Celular , Microscopia Crioeletrônica , Ebolavirus/ultraestrutura , Epitopos/imunologia , Feminino , Glicoproteínas/química , Glicoproteínas/imunologia , Doença pelo Vírus Ebola/virologia , Humanos , Concentração de Íons de Hidrogênio , Camundongos Endogâmicos BALB C , Modelos Moleculares , Primatas , Receptores Fc/metabolismo , Proteínas Recombinantes/imunologia , Viremia/imunologiaRESUMO
Hendra (HeV) and Nipah (NiV) viruses are emerging zoonotic pathogens in the Henipavirus genus causing outbreaks of disease with very high case fatality rates. Here, we report the first naturally occurring human monoclonal antibodies (mAbs) against HeV receptor binding protein (RBP). All isolated mAbs neutralized HeV, and some also neutralized NiV. Epitope binning experiments identified five major antigenic sites on HeV-RBP. Animal studies demonstrated that the most potent cross-reactive neutralizing mAbs, HENV-26 and HENV-32, protected ferrets in lethal models of infection with NiV Bangladesh 3 days after exposure. We solved the crystal structures of mAb HENV-26 in complex with both HeV-RBP and NiV-RBP and of mAb HENV-32 in complex with HeV-RBP. The studies reveal diverse sites of vulnerability on RBP recognized by potent human mAbs that inhibit virus by multiple mechanisms. These studies identify promising prophylactic antibodies and define protective epitopes that can be used in rational vaccine design.
Assuntos
Anticorpos Neutralizantes/imunologia , Anticorpos Antivirais/imunologia , Vírus Hendra/imunologia , Henipavirus/imunologia , Testes de Neutralização , Vírus Nipah/imunologia , Receptores Virais/imunologia , Sequência de Aminoácidos , Animais , Anticorpos Monoclonais/química , Anticorpos Monoclonais/isolamento & purificação , Antígenos Virais/imunologia , Sítios de Ligação , Ligação Competitiva , Encéfalo/patologia , Quirópteros/virologia , Reações Cruzadas/imunologia , Cristalografia por Raios X , Efrina-B2/metabolismo , Feminino , Furões/virologia , Humanos , Interferometria , Fígado/patologia , Modelos Moleculares , Ligação Proteica , Conformação Proteica , Domínios Proteicos , Receptores Virais/química , Receptores Virais/metabolismoRESUMO
Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is responsible for an unprecedented global pandemic of COVID-19. Animal models are urgently needed to study the pathogenesis of COVID-19 and to screen vaccines and treatments. We show that African green monkeys (AGMs) support robust SARS-CoV-2 replication and develop pronounced respiratory disease, which may more accurately reflect human COVID-19 cases than other nonhuman primate species. SARS-CoV-2 was detected in mucosal samples, including rectal swabs, as late as 15 days after exposure. Marked inflammation and coagulopathy in blood and tissues were prominent features. Transcriptome analysis demonstrated stimulation of interferon and interleukin-6 pathways in bronchoalveolar lavage samples and repression of natural killer cell- and T cell-associated transcripts in peripheral blood. Despite a slight waning in antibody titers after primary challenge, enhanced antibody and cellular responses contributed to rapid clearance after re-challenge with an identical strain. These data support the utility of AGM for studying COVID-19 pathogenesis and testing medical countermeasures.
Assuntos
COVID-19/imunologia , Modelos Animais de Doenças , Reinfecção/imunologia , SARS-CoV-2/imunologia , Linfócitos T/imunologia , Animais , Anticorpos Antivirais/imunologia , COVID-19/epidemiologia , COVID-19/virologia , Chlorocebus aethiops , Epidemias/prevenção & controle , Expressão Gênica/genética , Expressão Gênica/imunologia , Perfilação da Expressão Gênica , Humanos , Interferons/genética , Interferons/imunologia , Interferons/metabolismo , Células Matadoras Naturais/imunologia , Células Matadoras Naturais/metabolismo , Reinfecção/virologia , SARS-CoV-2/fisiologia , Linfócitos T/metabolismo , Linfócitos T/virologiaRESUMO
There are no approved treatments for Lassa fever (LF), which is responsible for thousands of deaths each year in West Africa. A major challenge in developing effective medical countermeasures against LF is the high diversity of circulating Lassa virus (LASV) strains with four recognized lineages and four proposed lineages. The recent resurgence of LASV in Nigeria caused by genetically distinct strains underscores this concern. Two LASV lineages (II and III) are dominant in Nigeria. Here, we show that combinations of two or three pan-lineage neutralizing human monoclonal antibodies (8.9F, 12.1F, 37.D) known as Arevirumab-2 or Arevirumab-3 can protect up to 100% of cynomolgus macaques against challenge with both lineage II and III LASV isolates when treatment is initiated at advanced stages of disease on day 8 after LASV exposure. This work demonstrates that it may be possible to develop postexposure interventions that can broadly protect against most strains of LASV.
Assuntos
Febre Lassa , Vírus Lassa , Animais , Humanos , Febre Lassa/prevenção & controle , África Ocidental , Anticorpos Monoclonais , Anticorpos Neutralizantes , Macaca fascicularisRESUMO
SignificanceConcern has increased about the pandemic potential of Nipah virus (NiV). Similar to SARS-CoV-2, NiV is an RNA virus that is transmitted by respiratory droplets. There are currently no NiV vaccines licensed for human use. While several preventive vaccines have shown promise in protecting animals against lethal NiV disease, most studies have assessed protection 1 mo after vaccination. However, in order to contain and control outbreaks, vaccines that can rapidly confer protection in days rather than months are needed. Here, we show that a recombinant vesicular stomatitis virus vector expressing the NiV glycoprotein can completely protect monkeys vaccinated 7 d prior to NiV exposure and 67% of animals vaccinated 3 d before NiV challenge.
Assuntos
Infecções por Henipavirus/veterinária , Vírus Nipah/imunologia , Doenças dos Primatas/prevenção & controle , Vacinas Sintéticas/imunologia , Vacinas Virais/imunologia , Animais , Anticorpos Neutralizantes , Anticorpos Antivirais/imunologia , Biomarcadores , Vetores Genéticos , Estimativa de Kaplan-Meier , Testes de Neutralização , Avaliação de Resultados em Cuidados de Saúde , Doenças dos Primatas/diagnóstico , Doenças dos Primatas/mortalidade , Doenças dos Primatas/virologia , Vacinação , Carga ViralRESUMO
The COVID-19 pandemic has reemphasized the need to identify safe and scalable therapeutics to slow or reverse symptoms of disease caused by newly emerging and reemerging viral pathogens. Recent clinical successes of monoclonal antibodies (mAbs) in therapy for viral infections demonstrate that mAbs offer a solution for these emerging biothreats. We have explored this with respect to Junin virus (JUNV), an arenavirus classified as a category A high-priority agent and the causative agent of Argentine hemorrhagic fever (AHF). There are currently no Food and Drug Administration-approved drugs available for preventing or treating AHF, although immune plasma from convalescent patients is used routinely to treat active infections. However, immune plasma is severely limited in quantity, highly variable in quality, and poses significant safety risks including the transmission of transfusion-borne diseases. mAbs offer a highly specific and consistently potent alternative to immune plasma that can be manufactured at large scale. We previously described a chimeric mAb, cJ199, that provided protection in a guinea pig model of AHF. To adapt this mAb to a format more suitable for clinical use, we humanized the mAb (hu199) and evaluated it in a cynomolgus monkey model of AHF with two JUNV isolates, Romero and Espindola. While untreated control animals experienced 100% lethality, all animals treated with hu199 at 6 d postinoculation (dpi) survived, and 50% of animals treated at 8 dpi survived. mAbs like hu199 may offer a safer, scalable, and more reproducible alternative to immune plasma for rare viral diseases that have epidemic potential.
Assuntos
Anticorpos Monoclonais Humanizados/farmacologia , Anticorpos Antivirais/farmacologia , Febre Hemorrágica Americana/prevenção & controle , Vírus Junin/metabolismo , Animais , Modelos Animais de Doenças , Feminino , Cobaias , Febre Hemorrágica Americana/sangue , Humanos , Macaca fascicularisRESUMO
BACKGROUND: The filovirus Bundibugyo virus (BDBV) causes severe disease with a mortality rate of approximately 20%-51%. The only licensed filovirus vaccine in the United States, Ervebo, consists of a recombinant vesicular stomatitis virus (rVSV) vector that expresses Ebola virus (EBOV) glycoprotein (GP). Ervebo was shown to rapidly protect against fatal Ebola disease in clinical trials; however, the vaccine is only indicated against EBOV. Recent outbreaks of other filoviruses underscore the need for additional vaccine candidates, particularly for BDBV infections. METHODS: To examine whether the rVSV vaccine candidate rVSVΔG/BDBV-GP could provide therapeutic protection against BDBV, we inoculated seven cynomolgus macaques with 1000 plaque-forming units of BDBV, administering rVSVΔG/BDBV-GP vaccine to 6 of them 20-23 minutes after infection. RESULTS: Five of the treated animals survived infection (83%) compared to an expected natural survival rate of 21% in this macaque model. All treated animals showed an early circulating immune response, while the untreated animal did not. Surviving animals showed evidence of both GP-specific IgM and IgG production, while animals that succumbed did not produce significant IgG. CONCLUSIONS: This small, proof-of-concept study demonstrated early treatment with rVSVΔG/BDBV-GP provides a survival benefit in this nonhuman primate model of BDBV infection, perhaps through earlier initiation of adaptive immunity.
Assuntos
Vacinas contra Ebola , Ebolavirus , Doença pelo Vírus Ebola , Estomatite Vesicular , Vacinas Virais , Animais , Estomatite Vesicular/prevenção & controle , Anticorpos Antivirais , Vesiculovirus/genética , Glicoproteínas/genética , Macaca fascicularis , Imunoglobulina GRESUMO
BACKGROUND: The primary route of infection by Ebola virus (EBOV) is through contact of mucosal surfaces. Few studies have explored infection of nonhuman primates (NHPs) via the oral mucosa, which is a probable portal of natural infection in humans. METHODS: To further characterize the pathogenesis of EBOV infection via the oral exposure route, we challenged cohorts of cynomolgus monkeys with low doses of EBOV variant Makona. RESULTS: Infection with 100 or 50 PFU of EBOV Makona via the oral route resulted in 50% and 83% lethality, respectively. Animals that progressed to fatal disease exhibited lymphopenia, marked coagulopathy, high viral loads, and increased levels of serum markers of inflammation and hepatic/renal injury. Survival in these cohorts was associated with milder fluctuations in leukocyte populations, lack of coagulopathy, and reduced or absent serum markers of inflammation and/or hepatic/renal function. Surprisingly, 2 surviving animals from the 100- and 50-PFU cohorts developed transient low-level viremia in the absence of other clinical signs of disease. Conversely, all animals in the 10 PFU cohort remained disease free and survived to the study end point. CONCLUSIONS: Our observations highlight the susceptibility of NHPs, and by extension, likely humans, to relatively low doses of EBOV via the oral route.
Assuntos
Ebolavirus , Doença pelo Vírus Ebola , Humanos , Animais , Modelos Animais de Doenças , Viremia , Macaca fascicularis , BiomarcadoresRESUMO
Marburg virus (MARV) causes a hemorrhagic fever disease in human and nonhuman primates with high levels of morbidity and mortality. Concerns about weaponization of aerosolized MARV have spurred the development of nonhuman primate (NHP) models of aerosol exposure. To address the potential threat of aerosol exposure, a monoclonal antibody that binds MARV glycoprotein was tested, MR186YTE, for its efficacy as a prophylactic. MR186YTE was administered intramuscularly to NHPs at 15 or 5 mg/kg 1 month prior to MARV aerosol challenge. Seventy-five percent (3/4) of the 15 mg/kg dose group and 50% (2/4) of the 5 mg/kg dose group survived. Serum analyses showed that the NHP dosed with 15 mg/kg that succumbed to infection developed an antidrug antibody response and therefore had no detectable MR186YTE at the time of challenge. These results suggest that intramuscular dosing of mAbs may be a clinically useful prophylaxis for MARV aerosol exposure.
Assuntos
Doença do Vírus de Marburg , Marburgvirus , Animais , Humanos , Anticorpos Monoclonais , Primatas , AerossóisRESUMO
BACKGROUND: The family Filoviridae consists of several virus members known to cause significant mortality and disease in humans. Among these, Ebola virus (EBOV), Marburg virus (MARV), Sudan virus (SUDV), and Bundibugyo virus (BDBV) are considered the deadliest. The vaccine, Ervebo, was shown to rapidly protect humans against Ebola disease, but is indicated only for EBOV infections with limited cross-protection against other filoviruses. Whether multivalent formulations of similar recombinant vesicular stomatitis virus (rVSV)-based vaccines could likewise confer rapid protection is unclear. METHODS: Here, we tested the ability of an attenuated, quadrivalent panfilovirus VesiculoVax vaccine (rVSV-Filo) to elicit fast-acting protection against MARV, EBOV, SUDV, and BDBV. Groups of cynomolgus monkeys were vaccinated 7 days before exposure to each of the 4 viral pathogens. All subjects (100%) immunized 1 week earlier survived MARV, SUDV, and BDBV challenge; 80% survived EBOV challenge. Survival correlated with lower viral load, higher glycoprotein-specific immunoglobulin G titers, and the expression of B-cell-, cytotoxic cell-, and antigen presentation-associated transcripts. CONCLUSIONS: These results demonstrate multivalent VesiculoVax vaccines are suitable for filovirus outbreak management. The highly attenuated nature of the rVSV-Filo vaccine may be preferable to the Ervebo "delta G" platform, which induced adverse events in a subset of recipients.
Assuntos
Vacinas contra Ebola , Ebolavirus , Doença pelo Vírus Ebola , Marburgvirus , Vacinas Virais , Humanos , Animais , Vacinas Atenuadas , Macaca fascicularis , Vesiculovirus/genética , Vírus da Estomatite Vesicular Indiana , Anticorpos AntiviraisRESUMO
BACKGROUND: Highly pathogenic filoviruses such as Ebola virus (EBOV) hold capacity for delivery by artificial aerosols, and thus potential for intentional misuse. Previous studies have shown that high doses of EBOV delivered by small-particle aerosol cause uniform lethality in nonhuman primates (NHPs), whereas only a few small studies have assessed lower doses in NHPs. METHODS: To further characterize the pathogenesis of EBOV infection via small-particle aerosol, we challenged cohorts of cynomolgus monkeys with low doses of EBOV variant Makona, which may help define risks associated with small particle aerosol exposures. RESULTS: Despite using challenge doses orders of magnitude lower than previous studies, infection via this route was uniformly lethal across all cohorts. Time to death was delayed in a dose-dependent manner between aerosol-challenged cohorts, as well as in comparison to animals challenged via the intramuscular route. Here, we describe the observed clinical and pathological details including serum biomarkers, viral burden, and histopathological changes leading to death. CONCLUSIONS: Our observations in this model highlight the striking susceptibility of NHPs, and likely humans, via small-particle aerosol exposure to EBOV and emphasize the need for further development of diagnostics and postexposure prophylactics in the event of intentional release via deployment of an aerosol-producing device.
Assuntos
Ebolavirus , Doença pelo Vírus Ebola , Humanos , Animais , Macaca fascicularis , Aerossóis , Carga ViralRESUMO
The severe death toll caused by the recent outbreak of Ebola virus disease reinforces the importance of developing ebolavirus prevention and treatment strategies. Here, we have explored the immunogenicity of a novel immunization regimen priming with vesicular stomatitis virus particles bearing Sudan Ebola virus (SUDV) glycoprotein (GP) that consists of GP1 & GP2 subunits and boosting with soluble SUDV GP in macaques, which developed robust neutralizing antibody (nAb) responses following immunizations. Moreover, EB46, a protective nAb isolated from one of the immune macaques, is found to target the GP1/GP2 interface, with GP-binding mode and neutralization mechanism similar to a number of ebolavirus nAbs from human and mouse, indicating that the ebolavirus GP1/GP2 interface is a common immunological target in different species. Importantly, selected immune macaque polyclonal sera showed nAb specificity similar to EB46 at substantial titers, suggesting that the GP1/GP2 interface region is a viable target for ebolavirus vaccine.Importance: The elicitation of sustained neutralizing antibody (nAb) responses against diverse ebolavirus strains remains as a high priority for the vaccine field. The most clinically advanced rVSV-ZEBOV vaccine could elicit moderate nAb responses against only one ebolavirus strain, EBOV, among the five ebolavirus strains, which last less than 6 months. Boost immunization strategies are desirable to effectively recall the rVSV vector-primed nAb responses to prevent infections in prospective epidemics, while an in-depth understanding of the specificity of immunization-elicited nAb responses is essential for improving vaccine performance. Here, using non-human primate animal model, we demonstrated that booster immunization with a stabilized trimeric soluble form of recombinant glycoprotein derived from the ebolavirus Sudan strain following the priming rVSV vector immunization led to robust nAb responses that substantially map to the subunit interface of ebolavirus glycoprotein, a common B cell repertoire target of multiple species including primates and rodents.
RESUMO
The current outbreak of Ebola virus in West Africa is unprecedented, causing more cases and fatalities than all previous outbreaks combined, and has yet to be controlled. Several post-exposure interventions have been employed under compassionate use to treat patients repatriated to Europe and the United States. However, the in vivo efficacy of these interventions against the new outbreak strain of Ebola virus is unknown. Here we show that lipid-nanoparticle-encapsulated short interfering RNAs (siRNAs) rapidly adapted to target the Makona outbreak strain of Ebola virus are able to protect 100% of rhesus monkeys against lethal challenge when treatment was initiated at 3 days after exposure while animals were viraemic and clinically ill. Although all infected animals showed evidence of advanced disease including abnormal haematology, blood chemistry and coagulopathy, siRNA-treated animals had milder clinical features and fully recovered, while the untreated control animals succumbed to the disease. These results represent the first, to our knowledge, successful demonstration of therapeutic anti-Ebola virus efficacy against the new outbreak strain in nonhuman primates and highlight the rapid development of lipid-nanoparticle-delivered siRNA as a countermeasure against this highly lethal human disease.
Assuntos
Ebolavirus/efeitos dos fármacos , Ebolavirus/genética , Doença pelo Vírus Ebola/terapia , Doença pelo Vírus Ebola/virologia , Nanopartículas/administração & dosagem , RNA Interferente Pequeno/administração & dosagem , RNA Interferente Pequeno/uso terapêutico , Animais , Sequência de Bases , Modelos Animais de Doenças , Ebolavirus/classificação , Feminino , Doença pelo Vírus Ebola/patologia , Doença pelo Vírus Ebola/prevenção & controle , Humanos , Macaca mulatta/virologia , Masculino , RNA Interferente Pequeno/farmacologia , Análise de Sobrevida , Fatores de Tempo , Resultado do Tratamento , Carga Viral/efeitos dos fármacosRESUMO
The family Filoviridae contains three genera, Ebolavirus (EBOV), Marburg virus, and Cuevavirus. Some members of the EBOV genus, including Zaire ebolavirus (ZEBOV), can cause lethal haemorrhagic fever in humans. During 2014 an unprecedented ZEBOV outbreak occurred in West Africa and is still ongoing, resulting in over 10,000 deaths, and causing global concern of uncontrolled disease. To meet this challenge a rapid-acting vaccine is needed. Many vaccine approaches have shown promise in being able to protect nonhuman primates against ZEBOV. In response to the current ZEBOV outbreak several of these vaccines have been fast tracked for human use. However, it is not known whether any of these vaccines can provide protection against the new outbreak Makona strain of ZEBOV. One of these approaches is a first-generation recombinant vesicular stomatitis virus (rVSV)-based vaccine expressing the ZEBOV glycoprotein (GP) (rVSV/ZEBOV). To address safety concerns associated with this vector, we developed two candidate, further-attenuated rVSV/ZEBOV vaccines. Both attenuated vaccines produced an approximately tenfold lower vaccine-associated viraemia compared to the first-generation vaccine and both provided complete, single-dose protection of macaques from lethal challenge with the Makona outbreak strain of ZEBOV.
Assuntos
Vacinas contra Ebola/administração & dosagem , Vacinas contra Ebola/imunologia , Ebolavirus/imunologia , Doença pelo Vírus Ebola/prevenção & controle , Doença pelo Vírus Ebola/virologia , Vacinas Atenuadas/imunologia , Vesiculovirus/genética , África Ocidental/epidemiologia , Animais , Anticorpos Antivirais/imunologia , República Democrática do Congo/epidemiologia , Vacinas contra Ebola/genética , Ebolavirus/classificação , Feminino , Vetores Genéticos/genética , Doença pelo Vírus Ebola/imunologia , Humanos , Imunoglobulina G/imunologia , Cinética , Macaca fascicularis , Masculino , Análise de Sobrevida , Vacinação , Vacinas Atenuadas/administração & dosagem , Vacinas Atenuadas/genética , Vesiculovirus/crescimento & desenvolvimentoRESUMO
BACKGROUND: Nipah virus (NiV) and Hendra virus (HeV) are zoonotic paramyxoviruses that cause severe disease in both animals and humans. There are no approved vaccines or treatments for use in humans; however, therapeutic treatment of both NiV and HeV infection in ferrets and non-human primates with a cross-reactive, neutralizing human monoclonal antibody (mAb), m102.4, targeting the G glycoprotein has been demonstrated. In a previous study, we isolated, characterized, and humanized a cross-reactive, neutralizing anti-F mAb (h5B3.1). The mAb h5B3.1 blocks the required F conformational change needed to facilitate membrane fusion and virus infection, and the epitope recognized by h5B3.1 has been structurally defined; however, the efficacy of h5B3.1 in vivo is unknown. METHODS: The post-infection antiviral activity of h5B3.1 was evaluated in vivo by administration in ferrets after NiV and HeV virus challenge. RESULTS: All subjects that received h5B3.1 from 1 to several days after infection with a high-dose, oral-nasal virus challenge were protected from disease, whereas all controls died. CONCLUSIONS: This is the first successful post-exposure antibody therapy for NiV and HeV using a humanized cross-reactive mAb targeting the F glycoprotein, and the findings suggest that a combination therapy targeting both F and G should be evaluated as a therapy for NiV/HeV infection.
Assuntos
Anticorpos Monoclonais/uso terapêutico , Vírus Hendra , Infecções por Henipavirus/terapia , Vírus Nipah , Proteínas Virais de Fusão/imunologia , Animais , Reações Cruzadas , Furões , Infecções por Henipavirus/prevenção & controle , Infecções por Henipavirus/virologia , HumanosRESUMO
The high case-fatality rates and potential for use as a biological weapon make Nipah virus (NiV) a significant public health concern. Previous studies assessing the pathogenic potential of NiV delivered by the aerosol route in African green monkeys (AGMs) used the Malaysia strain (NiVM), which has caused lower instances of respiratory illness and person-to-person transmission during human outbreaks than the Bangladesh strain (NiVB). Accordingly, we developed a small particle aerosol model of NiVB infection in AGMs. Consistent with other mucosal AGM models of NiVB infection, we achieved uniform lethality and disease pathogenesis reflective of that observed in humans.
Assuntos
Infecções por Henipavirus/virologia , Vírus Nipah/classificação , Vírus Nipah/fisiologia , Aerossóis , Animais , Infecções por Henipavirus/patologiaRESUMO
Due to the difficulty in conducting clinical trials for vaccines and treatments against Nipah virus (NiV), licensure will likely require animal models, most importantly non-human primates (NHPs). The NHP models of infection have primarily relied on intratracheal instillation or small particle aerosolization of NiV. However, neither of these routes adequately models natural mucosal exposure to NiV. To develop a more natural NHP model, we challenged African green monkeys with the Bangladesh strain of NiV by the intranasal route using the laryngeal mask airway (LMA) mucosal atomization device (MAD). LMA MAD exposure resulted in uniformly lethal disease that accurately reflected the human condition.
Assuntos
Chlorocebus aethiops , Modelos Animais de Doenças , Infecções por Henipavirus/virologia , Vírus Nipah , Administração Intranasal , Aerossóis , Animais , Feminino , Infecções por Henipavirus/mortalidade , Masculino , Carga Viral , Tropismo ViralRESUMO
BACKGROUND: The henipaviruses, Hendra virus (HeV) and Nipah virus (NiV), are capable of causing severe and often lethal respiratory and/or neurologic disease in animals and humans. Given the sporadic nature of henipavirus outbreaks, licensure of vaccines and therapeutics for human use will likely require demonstration of efficacy in animal models that faithfully reproduce the human condition. Currently, the African green monkey (AGM) best mimics human henipavirus-induced disease. METHODS: The pathogenic potential of HeV and both strains of NiV (Malaysia, Bangladesh) was assessed in cynomolgus monkeys and compared with henipavirus-infected historical control AGMs. Multiplex gene and protein expression assays were used to compare host responses. RESULTS: In contrast to AGMs, in which henipaviruses cause severe and usually lethal disease, HeV and NiVs caused only mild or asymptomatic infections in macaques. All henipaviruses replicated in macaques with similar kinetics as in AGMs. Infection in macaques was associated with activation and predicted recruitment of cytotoxic CD8+ T cells, Th1 cells, IgM+ B cells, and plasma cells. Conversely, fatal outcome in AGMs was associated with aberrant innate immune signaling, complement dysregulation, Th2 skewing, and increased secretion of MCP-1. CONCLUSION: The restriction factors identified in macaques can be harnessed for development of effective countermeasures against henipavirus disease.
Assuntos
Vírus Hendra , Infecções por Henipavirus/veterinária , Imunidade Celular , Imunidade Humoral , Macaca fascicularis , Vírus Nipah , Animais , Infecções por Henipavirus/virologia , Masculino , Doenças dos Macacos/imunologia , Doenças dos Macacos/virologia , Carga Viral , Tropismo ViralRESUMO
We recently reported the development of the first African green monkey (AGM) model for COVID-19 based on a combined liquid intranasal (i.n.) and intratracheal (i.t.) exposure to severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). Here, we followed up on this work by assessing an i.n. particle only route of exposure using the LMA mucosal atomization device (MAD). Six AGMs were infected with SARS-CoV-2; three animals were euthanized near the peak stage of virus replication (day 5) and three animals were euthanized during the early convalescence period (day 34). All six AGMs supported robust SARS-CoV-2 replication and developed respiratory disease. Evidence of coagulation dysfunction as noted by a transient increases in aPTT and circulating levels of fibrinogen was observed in all AGMs. The level of SARS-CoV-2 replication and lung pathology was not quite as pronounced as previously reported with AGMs exposed by the combined i.n. and i.t. routes; however, SARS-CoV-2 RNA was detected in nasal swabs of some animals as late as day 15 and rectal swabs as late as day 28 after virus challenge. Of particular importance to this study, all three AGMs that were followed until the early convalescence stage of COVID-19 showed substantial lung pathology at necropsy as evidenced by multifocal chronic interstitial pneumonia and increased collagen deposition in alveolar walls despite the absence of detectable SARS-CoV-2 in any of the lungs of these animals. These findings are consistent with human COVID-19 further demonstrating that the AGM faithfully reproduces the human condition.