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Gao F, He C, Liu M, Yuan P, Tian S, Zheng M, Zhang L, Zhou X, Xu F, Luo J, Li X. Cross-reactive immune responses to monkeypox virus induced by MVA vaccination in mice. Virol J 2023; 20:126. [PMID: 37337226 DOI: 10.1186/s12985-023-02085-0] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/23/2023] [Accepted: 05/28/2023] [Indexed: 06/21/2023] Open
Abstract
Mpox (monkeypox) infection cases increased recently in non-Mpox outbreak areas, potentially causing an international threat. The desire to defend against a potential outbreak has led to renewed efforts to develop Mpox vaccines. In this report, mice were immunized with various doses of modified vaccinia virus Ankara (MVA) to evaluate the cross-reactive immune response of MVA immunization against protective antigens of the current monkeypox virus. We demonstrated that MVA induced specific antibodies against protective antigens (A29, A35, B6, M1, H3, and I1), mediating the neutralization abilities against the MVA and the monkeypox virus (MPXV). Moreover, recombinant protective antigens of the MPXV elicited cross-binding and cross-neutralizing activities for MVA. Hence, the MVA induced cross-reactive immune responses, which may guide future efforts to develop vaccines against the recent MPXV. Notably, compared to the other protective antigens, the predominant A29 and M1 antigens mediated higher cross-neutralizing immune responses against the MVA, which could serve as antigen targets for novel orthologous orthopoxvirus vaccine.
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Affiliation(s)
- Feixia Gao
- Shanghai Institute of Biological Products, Shanghai, China
| | - Cheng He
- Shanghai Institute of Biological Products, Shanghai, China
| | - Min Liu
- Shanghai Institute of Biological Products, Shanghai, China
| | - Ping Yuan
- Shanghai Institute of Biological Products, Shanghai, China
| | - Shihua Tian
- Shanghai Institute of Biological Products, Shanghai, China
| | - Mei Zheng
- Shanghai Institute of Biological Products, Shanghai, China
| | - Linya Zhang
- Shanghai Institute of Biological Products, Shanghai, China
| | - Xu Zhou
- Shanghai Institute of Biological Products, Shanghai, China
| | | | - Jian Luo
- Shanghai Institute of Biological Products, Shanghai, China.
| | - Xiuling Li
- Shanghai Institute of Biological Products, Shanghai, China.
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2
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Zhang RR, Wang ZJ, Zhu YL, Tang W, Zhou C, Zhao SQ, Wu M, Ming T, Deng YQ, Chen Q, Jin NY, Ye Q, Li X, Qin CF. Rational development of multicomponent mRNA vaccine candidates against mpox. Emerg Microbes Infect 2023; 12:2192815. [PMID: 36947428 PMCID: PMC10071941 DOI: 10.1080/22221751.2023.2192815] [Citation(s) in RCA: 25] [Impact Index Per Article: 25.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/23/2023]
Abstract
The re-emerging mpox (formerly monkeypox) virus (MPXV), a member of Orthopoxvirus genus together with variola virus (VARV) and vaccinia virus (VACV), has led to public health emergency of international concern since July, 2022. Inspired by the unprecedent success of coronavirus disease 2019 (COVID-19) mRNA vaccines, the development of a safe and effective mRNA vaccine against MPXV is of high priority. Based on our established lipid nanoparticle (LNP)-encapsulated mRNA vaccine platform, we rationally constructed and prepared a panel of multicomponent MPXV vaccine candidates encoding different combinations of viral antigens including M1R, E8L, A29L, A35R and B6R. In vitro and in vivo characterization demonstrated that two immunizations of all mRNA vaccine candidates elicit a robust antibody response as well as antigen specific Th1-biased cellular response in mice. Importantly, the penta- and tetra-component vaccine candidates AR-MPXV5 and AR-MPXV4a showed superior capability of inducing neutralizing antibodies as well as of protecting from VACV challenge in mice. Our study provides critical insights to understand the protection mechanism of MPXV infection and direct evidence supporting further clinical development of these multicomponent mRNA vaccine candidates.
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Affiliation(s)
- Rong-Rong Zhang
- State Key Laboratory of Pathogen and Biosecurity, Beijing Institute of Microbiology and Epidemiology, Beijing 100071, China
| | - Zheng-Jian Wang
- State Key Laboratory of Pathogen and Biosecurity, Beijing Institute of Microbiology and Epidemiology, Beijing 100071, China
| | - Yi-Long Zhu
- Changchun Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Changchun, China
- Academicians Workstation of Jilin Province, Changchun University of Chinese Medicine, Changchun, 130117, China
| | - Wei Tang
- State Key Laboratory of Pathogen and Biosecurity, Beijing Institute of Microbiology and Epidemiology, Beijing 100071, China
| | - Chao Zhou
- State Key Laboratory of Pathogen and Biosecurity, Beijing Institute of Microbiology and Epidemiology, Beijing 100071, China
| | - Suo-Qun Zhao
- State Key Laboratory of Pathogen and Biosecurity, Beijing Institute of Microbiology and Epidemiology, Beijing 100071, China
| | - Mei Wu
- State Key Laboratory of Pathogen and Biosecurity, Beijing Institute of Microbiology and Epidemiology, Beijing 100071, China
| | - Tao Ming
- State Key Laboratory of Pathogen and Biosecurity, Beijing Institute of Microbiology and Epidemiology, Beijing 100071, China
| | - Yong-Qiang Deng
- State Key Laboratory of Pathogen and Biosecurity, Beijing Institute of Microbiology and Epidemiology, Beijing 100071, China
| | - Qi Chen
- State Key Laboratory of Pathogen and Biosecurity, Beijing Institute of Microbiology and Epidemiology, Beijing 100071, China
| | - Ning-Yi Jin
- Changchun Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Changchun, China
| | - Qing Ye
- State Key Laboratory of Pathogen and Biosecurity, Beijing Institute of Microbiology and Epidemiology, Beijing 100071, China
| | - Xiao Li
- Changchun Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Changchun, China
| | - Cheng-Feng Qin
- State Key Laboratory of Pathogen and Biosecurity, Beijing Institute of Microbiology and Epidemiology, Beijing 100071, China
- Research Unit of Discovery and Tracing of Natural Focus Diseases, Chinese Academy of Medical Sciences, Beijing 100071, China
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Martín-Delgado MC, Martín Sánchez FJ, Martínez-Sellés M, Molero García JM, Moreno Guillén S, Rodríguez-Artalejo FJ, Ruiz-Galiana J, Cantón R, De Lucas Ramos P, García-Botella A, García-Lledó A, Hernández-Sampelayo T, Gómez-Pavón J, González Del Castillo J, Muñoz P, Valerio M, Catalán P, Burillo A, Cobo A, Alcamí A, Bouza E. Monkeypox in humans: a new outbreak. REVISTA ESPANOLA DE QUIMIOTERAPIA : PUBLICACION OFICIAL DE LA SOCIEDAD ESPANOLA DE QUIMIOTERAPIA 2022; 35:509-518. [PMID: 35785957 PMCID: PMC9728594 DOI: 10.37201/req/059.2022] [Citation(s) in RCA: 22] [Impact Index Per Article: 11.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Subscribe] [Scholar Register] [Received: 06/27/2022] [Accepted: 07/01/2022] [Indexed: 12/24/2022]
Abstract
Infection caused by Monkeypox Virus (MPVX) has small rodents as its natural reservoir and both monkeys and humans are occasional hosts. The causative agent is an Orthopoxvirus (MPVX) that was isolated in monkeys in 1958 and proved capable of passing to humans in 1970. It remained contained in Africa, causing isolated episodes of infection, until 2003 when an outbreak occurred in the United States following importation of animals from that continent. Since then, anecdotal cases have continued to be reported outside Africa, usually very clearly linked to travelers to those countries, but in May 2022, a broad outbreak of this disease has begun, now affecting several continents, with the emergence of human cases of MPVX (H-MPVX) infection mainly among Men that have Sex with Men (MSM). The disease has an incubation time ranging from 5 to 15 days and is characterized by the presence of pustules, fever, malaise and headache. The presence of significant regional lymphadenopathy is a differential feature with episodes of classical smallpox. Proctitis and pharyngitis, with minimal skin lesions, may be another form of presentation. Diagnosis can be confirmed by PCR testing of lesions or by demonstration of MPVX in other body fluids or tissues, although in the appropriate epidemiologic setting the clinical picture is highly suggestive of the disease. Effective drug treatment has been developed as part of programs to protect against potential bioterrorist agents and smallpox vaccinees are known to have high protection against monkeypox. New vaccines are available, but neither the drugs nor the vaccines are yet freely available on the market. The prognosis of the disease appears, at least in adults in developed countries, to be good, with very low mortality figures and much less aggressive behavior than that described in classical smallpox. Isolation measures, essential for the control of the outbreak, have been published by the health authorities.
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Affiliation(s)
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | - E Bouza
- Servicio de Microbiología Clínica y Enfermedades Infecciosas del Hospital General Universitario Gregorio Marañón, Universidad Complutense. CIBERES. Ciber de Enfermedades Respiratorias. Madrid, Spain.
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A nucleic acid-based orthopoxvirus vaccine targeting the vaccinia virus L1, A27, B5 and A33 proteins protects rabbits against lethal rabbitpox virus aerosol challenge. J Virol 2021; 96:e0150421. [PMID: 34851148 DOI: 10.1128/jvi.01504-21] [Citation(s) in RCA: 24] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022] Open
Abstract
In the age of COVID, nucleic acid vaccines have garnered much attention, at least in part, because of the simplicity of construction, production, and flexibility to adjust and adapt to an evolving outbreak. Orthopoxviruses remain a threat on multiple fronts, especially as emerging zoonosis. In response, we developed a DNA vaccine, termed 4pox, that protected nonhuman primates against monkeypox virus (MPXV) induced severe disease. Here, we examined the protective efficacy of the 4pox DNA vaccine delivered by intramuscular (i.m.) electroporation (EP) in rabbits challenged with aerosolized rabbitpox virus (RPXV), a model that recapitulates the respiratory route of exposure and low dose associated with natural smallpox exposure in humans. We found that 4pox vaccinated rabbits developed immunogen-specific antibodies, including neutralizing antibodies and did not develop any clinical disease, indicating protection against aerosolized RPXV. In contrast, unvaccinated animals developed significant signs of disease, including lesions, and were euthanized. These findings demonstrate that an unformulated, non-adjuvanted DNA vaccine delivered (i.m.) can protect against an aerosol exposure. Importance The eradication of smallpox and subsequent cessation of vaccination has left a majority of the population susceptible to variola virus or other emerging poxvirus. This is exemplified by human monkeypox, as evidenced by the increase in reported endemic and imported cases over the past decades. Therefore, a malleable vaccine technology that can be mass produced, and doesn't require complex conditions for distribution and storage is sought. Herein, we show that a DNA vaccine, in the absence of a specialized formulation or adjuvant, can protect against a lethal aerosol insult of rabbitpox virus.
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Cheminay C, Körner J, Bernig C, Brückel M, Feigl M, Schletz M, Suter M, Chaplin P, Volkmann A. A single vaccination with non-replicating MVA at birth induces both immediate and long-term protective immune responses. Vaccine 2018; 36:2427-2434. [PMID: 29599088 DOI: 10.1016/j.vaccine.2018.03.048] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/01/2017] [Revised: 11/17/2017] [Accepted: 03/16/2018] [Indexed: 11/16/2022]
Abstract
Newborns are considered difficult to protect against infections shortly after birth, due to their ineffective immune system that shows quantitative and qualitative differences compared to adults. However, here we show that a single vaccination of mice at birth with a replication-deficient live vaccine Modified Vaccinia Ankara [MVA] efficiently induces antigen-specific B- and T-cells that fully protect against a lethal Ectromelia virus challenge. Protection was induced within 2 weeks and using genetically modified mice we show that this protection was mainly T-cell dependent. Persisting immunological T-cell memory and neutralizing antibodies were obtained with the single vaccination. Thus, MVA administered as early as at birth induced immediate and long-term protection against an otherwise fatal disease and appears attractive as a new generation smallpox vaccine that is effective also in children. Moreover, it may have the potential to serve as platform for childhood vaccines as indicated by measles specific T- and B-cell responses induced in newborn mice vaccinated with recombinant MVA expressing measles antigens.
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Affiliation(s)
- Cédric Cheminay
- Bavarian Nordic GmbH, Fraunhoferstrasse 13, D-82152 Martinsried, Germany
| | - Jana Körner
- Bavarian Nordic GmbH, Fraunhoferstrasse 13, D-82152 Martinsried, Germany
| | - Constanze Bernig
- Bavarian Nordic GmbH, Fraunhoferstrasse 13, D-82152 Martinsried, Germany
| | - Michael Brückel
- Bavarian Nordic GmbH, Fraunhoferstrasse 13, D-82152 Martinsried, Germany
| | - Markus Feigl
- Bavarian Nordic GmbH, Fraunhoferstrasse 13, D-82152 Martinsried, Germany
| | - Martin Schletz
- Bavarian Nordic GmbH, Fraunhoferstrasse 13, D-82152 Martinsried, Germany
| | - Mark Suter
- University of Zürich, Dekanat Vetsuisse-Fakultät Immunology, Winterthurerstrasse 204, CH-8057 Zürich, Switzerland
| | - Paul Chaplin
- Bavarian Nordic GmbH, Fraunhoferstrasse 13, D-82152 Martinsried, Germany
| | - Ariane Volkmann
- Bavarian Nordic GmbH, Fraunhoferstrasse 13, D-82152 Martinsried, Germany.
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Modified Vaccinia Ankara Virus Vaccination Provides Long-Term Protection against Nasal Rabbitpox Virus Challenge. CLINICAL AND VACCINE IMMUNOLOGY : CVI 2016; 23:648-51. [PMID: 27146001 DOI: 10.1128/cvi.00216-16] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/26/2016] [Accepted: 04/29/2016] [Indexed: 02/08/2023]
Abstract
Modified vaccinia Ankara virus (MVA) is a smallpox vaccine candidate. This study was performed to determine if MVA vaccination provides long-term protection against rabbitpox virus (RPXV) challenge, an animal model of smallpox. Two doses of MVA provided 100% protection against a lethal intranasal RPXV challenge administered 9 months after vaccination.
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7
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Tree JA, Hall G, Rees P, Vipond J, Funnell SGP, Roberts AD. Repeated high-dose (5 × 10(8) TCID50) toxicity study of a third generation smallpox vaccine (IMVAMUNE) in New Zealand white rabbits. Hum Vaccin Immunother 2016; 12:1795-801. [PMID: 26836234 PMCID: PMC4964806 DOI: 10.1080/21645515.2015.1134070] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/21/2015] [Revised: 12/02/2015] [Accepted: 12/15/2015] [Indexed: 11/04/2022] Open
Abstract
Concern over the release of variola virus as an agent of bioterrorism remains high and a rapid vaccination regimen is desirable for use in the event of a confirmed release of virus. A single, high-dose (5×10(8) TCID50) of Bavarian Nordic's IMVAMUNE was tested in a Phase-II clinical trial, in humans, as a substitute for the standard (1×10(8) TCID50), using a 2-dose, 28-days apart regimen. Prior to this clinical trial taking place a Good Laboratory Practice, repeated high-dose, toxicology study was performed using IMVAMUNE, in New Zealand white rabbits and the results are reported here. Male and female rabbits were dosed twice, subcutaneously, with 5×10(8) TCID50 of IMVAMUNE (test) or saline (control), 7-days apart. The clinical condition, body-weight, food consumption, haematology, blood chemistry, immunogenicity, organ-weight, and macroscopic and microscopic pathology were investigated. Haematological investigations indicated changes within the white blood cell profile that were attributed to treatment with IMVAMUNE; these comprised slight increases in neutrophil and monocyte numbers, on study days 1-3 and a marginal increase in lymphocyte numbers on day 10. Macroscopic pathology revealed reddening at the sites of administration and thickened skin in IMVAMUNE, treated animals. After the second dose of IMVAMUNE 9/10 rabbits seroconverted, as detected by antibody ELISA on day 10, by day 21, 10/10 rabbits seroconverted. Treatment-related changes were not detected in other parameters. In conclusion, the subcutaneous injection of 2 high-doses of IMVAMUNE, to rabbits, was well tolerated producing only minor changes at the site of administration. Vaccinia-specific antibodies were raised in IMVAMUNE-vaccinated rabbits only.
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Affiliation(s)
- Julia A. Tree
- National Infection Service, Public Health England, Porton Down, Salisbury, Wiltshire, UK
| | - Graham Hall
- National Infection Service, Public Health England, Porton Down, Salisbury, Wiltshire, UK
| | - Peter Rees
- Envigo CRS Limited, Occold, Eye, Suffolk, UK
| | - Julia Vipond
- National Infection Service, Public Health England, Porton Down, Salisbury, Wiltshire, UK
| | - Simon G. P. Funnell
- National Infection Service, Public Health England, Porton Down, Salisbury, Wiltshire, UK
| | - Allen D. Roberts
- National Infection Service, Public Health England, Porton Down, Salisbury, Wiltshire, UK
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8
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Greenberg RN, Hay CM, Stapleton JT, Marbury TC, Wagner E, Kreitmeir E, Röesch S, von Krempelhuber A, Young P, Nichols R, Meyer TP, Schmidt D, Weigl J, Virgin G, Arndtz-Wiedemann N, Chaplin P. A Randomized, Double-Blind, Placebo-Controlled Phase II Trial Investigating the Safety and Immunogenicity of Modified Vaccinia Ankara Smallpox Vaccine (MVA-BN®) in 56-80-Year-Old Subjects. PLoS One 2016; 11:e0157335. [PMID: 27327616 PMCID: PMC4915701 DOI: 10.1371/journal.pone.0157335] [Citation(s) in RCA: 39] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/30/2015] [Accepted: 05/27/2016] [Indexed: 01/28/2023] Open
Abstract
BACKGROUND Modified Vaccinia Ankara MVA-BN® is a live, highly attenuated, viral vaccine under advanced development as a non-replicating smallpox vaccine. In this Phase II trial, the safety and immunogenicity of Modified Vaccinia Ankara MVA-BN® (MVA) was assessed in a 56-80 years old population. METHODS MVA with a virus titer of 1 x 108 TCID50/dose was administered via subcutaneous injection to 56-80 year old vaccinia-experienced subjects (N = 120). Subjects received either two injections of MVA (MM group) or one injection of Placebo and one injection of MVA (PM group) four weeks apart. Safety was evaluated by assessment of adverse events (AE), focused physical exams, electrocardiogram recordings and safety laboratories. Solicited AEs consisted of a set of pre-defined expected local reactions (erythema, swelling, pain, pruritus, and induration) and systemic symptoms (body temperature, headache, myalgia, nausea and fatigue) and were recorded on a memory aid for an 8-day period following each injection. The immunogenicity of the vaccine was evaluated in terms of humoral immune responses measured with a vaccinia-specific enzyme-linked immunosorbent assay (ELISA) and a plaque reduction neutralization test (PRNT) before and at different time points after vaccination. RESULTS Vaccinations were well tolerated by all subjects. No serious adverse event related to MVA and no case of myopericarditis was reported. The overall incidence of unsolicited AEs was similar in both groups. For both groups immunogenicity responses two weeks after the final vaccination (i.e. Visit 4) were as follows: Seroconversion (SC) rates (doubling of titers from baseline) in vaccine specific antibody titers measured by ELISA were 83.3% in Group MM and 82.8% in Group PM (difference 0.6% with 95% exact CI [-13.8%, 15.0%]), and 90.0% for Group MM and 77.6% for Group PM measured by PRNT (difference 12.4% with 95% CI of [-1.1%, 27.0%]). Geometric mean titers (GMT) measured by ELISA two weeks after the final vaccination for Group MM were 804.1 and 605.8 for Group PM (with ratio of GMTs of 1.33 with 95% CI of [0.96, 1.84]). Similarly, GMTs measured by PRNT were 210.3 for Group MM and 126.7 for Group PM (with ratio 1.66 and 95% CI [0.95, 2.90]). CONCLUSIONS One or two doses of MVA were safe and immunogenic in a 56-80 years old vaccinia-experienced population. No cases of myopericarditis were observed following vaccinations with MVA. The safety, reactogenicity and immunogenicity were similar to that seen in younger (18-55 year old) healthy populations as investigated in other MVA trials. The results suggest that a single dose of MVA in a 56-80 years old population was well tolerated and sufficient to rapidly boost the long-term B cell memory response induced by a prior vaccination with a traditional smallpox vaccine. TRIAL REGISTRATION ClinicalTrials.gov NCT00857493.
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Affiliation(s)
- Richard N. Greenberg
- University of Kentucky School of Medicine, MN663 Medical Science Bldg., 800 Rose Street, Lexington, KY, 40536, United States of America
| | - Christine M. Hay
- University of Iowa, SW54, GH, 200 Hawkins Drive, UHC, Iowa City, IA, 52242, United States of America
| | - Jack T. Stapleton
- University of Rochester Medical Center School of Medicine and Dentistry, 601 Elmwood Avenue, Box 689, Rochester, NY, 14642, United States of America
| | - Thomas C. Marbury
- Orlando Clinical Research Center, 5055 South Orange Avenue, Orlando, FL, 32809, United States of America
| | - Eva Wagner
- Bavarian Nordic GmbH, Fraunhoferstrasse 13, 82152 Martinsried, Germany
| | - Eva Kreitmeir
- Bavarian Nordic GmbH, Fraunhoferstrasse 13, 82152 Martinsried, Germany
| | - Siegfried Röesch
- Bavarian Nordic GmbH, Fraunhoferstrasse 13, 82152 Martinsried, Germany
| | | | - Philip Young
- Bavarian Nordic GmbH, Fraunhoferstrasse 13, 82152 Martinsried, Germany
| | - Richard Nichols
- Bavarian Nordic GmbH, Fraunhoferstrasse 13, 82152 Martinsried, Germany
| | - Thomas P. Meyer
- Bavarian Nordic GmbH, Fraunhoferstrasse 13, 82152 Martinsried, Germany
| | - Darja Schmidt
- Bavarian Nordic GmbH, Fraunhoferstrasse 13, 82152 Martinsried, Germany
| | - Josef Weigl
- Bavarian Nordic GmbH, Fraunhoferstrasse 13, 82152 Martinsried, Germany
| | - Garth Virgin
- Bavarian Nordic GmbH, Fraunhoferstrasse 13, 82152 Martinsried, Germany
| | | | - Paul Chaplin
- Bavarian Nordic GmbH, Fraunhoferstrasse 13, 82152 Martinsried, Germany
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Parker S, Crump R, Foster S, Hartzler H, Hembrador E, Lanier ER, Painter G, Schriewer J, Trost LC, Buller RM. Co-administration of the broad-spectrum antiviral, brincidofovir (CMX001), with smallpox vaccine does not compromise vaccine protection in mice challenged with ectromelia virus. Antiviral Res 2014; 111:42-52. [PMID: 25128688 PMCID: PMC9533899 DOI: 10.1016/j.antiviral.2014.08.003] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/23/2014] [Revised: 07/31/2014] [Accepted: 08/04/2014] [Indexed: 12/02/2022]
Abstract
Natural orthopoxvirus outbreaks such as vaccinia, cowpox, cattlepox and buffalopox continue to cause morbidity in the human population. Monkeypox virus remains a significant agent of morbidity and mortality in Africa. Furthermore, monkeypox virus’s broad host-range and expanding environs make it of particular concern as an emerging human pathogen. Monkeypox virus and variola virus (the etiological agent of smallpox) are both potential agents of bioterrorism. The first line response to orthopoxvirus disease is through vaccination with first-generation and second-generation vaccines, such as Dryvax and ACAM2000. Although these vaccines provide excellent protection, their widespread use is impeded by the high level of adverse events associated with vaccination using live, attenuated virus. It is possible that vaccines could be used in combination with antiviral drugs to reduce the incidence and severity of vaccine-associated adverse events, or as a preventive in individuals with uncertain exposure status or contraindication to vaccination. We have used the intranasal mousepox (ectromelia) model to evaluate the efficacy of vaccination with Dryvax or ACAM2000 in conjunction with treatment using the broad spectrum antiviral, brincidofovir (BCV, CMX001). We found that co-treatment with BCV reduced the severity of vaccination-associated lesion development. Although the immune response to vaccination was quantifiably attenuated, vaccination combined with BCV treatment did not alter the development of full protective immunity, even when administered two days following ectromelia challenge. Studies with a non-replicating vaccine, ACAM3000 (MVA), confirmed that BCV’s mechanism of attenuating the immune response following vaccination with live virus was, as expected, by limiting viral replication and not through inhibition of the immune system. These studies suggest that, in the setting of post-exposure prophylaxis, co-administration of BCV with vaccination should be considered a first response to a smallpox emergency in subjects of uncertain exposure status or as a means of reduction of the incidence and severity of vaccine-associated adverse events.
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Affiliation(s)
- Scott Parker
- Saint Louis University School of Medicine, 1100 S. Grand Blvd., St. Louis, MO 63104, United States
| | - Ryan Crump
- Saint Louis University School of Medicine, 1100 S. Grand Blvd., St. Louis, MO 63104, United States
| | - Scott Foster
- Chimerix Inc., 2505 Meridian Parkway, Suite 340, Durham, NC 27713, United States
| | - Hollyce Hartzler
- Saint Louis University School of Medicine, 1100 S. Grand Blvd., St. Louis, MO 63104, United States
| | - Ed Hembrador
- Saint Louis University School of Medicine, 1100 S. Grand Blvd., St. Louis, MO 63104, United States
| | - E Randall Lanier
- Chimerix Inc., 2505 Meridian Parkway, Suite 340, Durham, NC 27713, United States
| | - George Painter
- Chimerix Inc., 2505 Meridian Parkway, Suite 340, Durham, NC 27713, United States
| | - Jill Schriewer
- Saint Louis University School of Medicine, 1100 S. Grand Blvd., St. Louis, MO 63104, United States
| | - Lawrence C Trost
- Chimerix Inc., 2505 Meridian Parkway, Suite 340, Durham, NC 27713, United States
| | - R Mark Buller
- Saint Louis University School of Medicine, 1100 S. Grand Blvd., St. Louis, MO 63104, United States.
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10
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Keckler MS, Reynolds MG, Damon IK, Karem KL. The effects of post-exposure smallpox vaccination on clinical disease presentation: addressing the data gaps between historical epidemiology and modern surrogate model data. Vaccine 2013; 31:5192-201. [PMID: 23994378 DOI: 10.1016/j.vaccine.2013.08.039] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/14/2013] [Revised: 08/05/2013] [Accepted: 08/13/2013] [Indexed: 11/28/2022]
Abstract
Decades after public health interventions - including pre- and post-exposure vaccination - were used to eradicate smallpox, zoonotic orthopoxvirus outbreaks and the potential threat of a release of variola virus remain public health concerns. Routine prophylactic smallpox vaccination of the public ceased worldwide in 1980, and the adverse event rate associated with the currently licensed live vaccinia virus vaccine makes reinstatement of policies recommending routine pre-exposure vaccination unlikely in the absence of an orthopoxvirus outbreak. Consequently, licensing of safer vaccines and therapeutics that can be used post-orthopoxvirus exposure is necessary to protect the global population from these threats. Variola virus is a solely human pathogen that does not naturally infect any other known animal species. Therefore, the use of surrogate viruses in animal models of orthopoxvirus infection is important for the development of novel vaccines and therapeutics. Major complications involved with the use of surrogate models include both the absence of a model that accurately mimics all aspects of human smallpox disease and a lack of reproducibility across model species. These complications limit our ability to model post-exposure vaccination with newer vaccines for application to human orthopoxvirus outbreaks. This review seeks to (1) summarize conclusions about the efficacy of post-exposure smallpox vaccination from historic epidemiological reports and modern animal studies; (2) identify data gaps in these studies; and (3) summarize the clinical features of orthopoxvirus-associated infections in various animal models to identify those models that are most useful for post-exposure vaccination studies. The ultimate purpose of this review is to provide observations and comments regarding available model systems and data gaps for use in improving post-exposure medical countermeasures against orthopoxviruses.
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Affiliation(s)
- M Shannon Keckler
- Centers for Disease Control and Prevention, Division of High-Consequence Pathogens and Pathology, Poxvirus and Rabies Branch, United States.
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11
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Hatch GJ, Graham VA, Bewley KR, Tree JA, Dennis M, Taylor I, Funnell SGP, Bate SR, Steeds K, Tipton T, Bean T, Hudson L, Atkinson DJ, McLuckie G, Charlwood M, Roberts ADG, Vipond J. Assessment of the protective effect of Imvamune and Acam2000 vaccines against aerosolized monkeypox virus in cynomolgus macaques. J Virol 2013; 87:7805-15. [PMID: 23658452 PMCID: PMC3700201 DOI: 10.1128/jvi.03481-12] [Citation(s) in RCA: 82] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/18/2013] [Accepted: 04/30/2013] [Indexed: 12/17/2022] Open
Abstract
To support the licensure of a new and safer vaccine to protect people against smallpox, a monkeypox model of infection in cynomolgus macaques, which simulates smallpox in humans, was used to evaluate two vaccines, Acam2000 and Imvamune, for protection against disease. Animals vaccinated with a single immunization of Imvamune were not protected completely from severe and/or lethal infection, whereas those receiving either a prime and boost of Imvamune or a single immunization with Acam2000 were protected completely. Additional parameters, including clinical observations, radiographs, viral load in blood, throat swabs, and selected tissues, vaccinia virus-specific antibody responses, immunophenotyping, extracellular cytokine levels, and histopathology were assessed. There was no significant difference (P > 0.05) between the levels of neutralizing antibody in animals vaccinated with a single immunization of Acam2000 (132 U/ml) and the prime-boost Imvamune regime (69 U/ml) prior to challenge with monkeypox virus. After challenge, there was evidence of viral excretion from the throats of 2 of 6 animals in the prime-boost Imvamune group, whereas there was no confirmation of excreted live virus in the Acam2000 group. This evaluation of different human smallpox vaccines in cynomolgus macaques helps to provide information about optimal vaccine strategies in the absence of human challenge studies.
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Affiliation(s)
- Graham J Hatch
- Microbiological Services, Public Health England, Salisbury, Wiltshire, United Kingdom.
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12
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Parker S, Chen NG, Foster S, Hartzler H, Hembrador E, Hruby D, Jordan R, Lanier R, Painter G, Painter W, Sagartz JE, Schriewer J, Mark Buller R. Evaluation of disease and viral biomarkers as triggers for therapeutic intervention in respiratory mousepox - an animal model of smallpox. Antiviral Res 2012; 94:44-53. [PMID: 22381921 PMCID: PMC3722602 DOI: 10.1016/j.antiviral.2012.02.005] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/01/2011] [Revised: 12/16/2011] [Accepted: 02/08/2012] [Indexed: 11/26/2022]
Abstract
The human population is currently faced with the potential use of natural or recombinant variola and monkeypox viruses as biological weapons. Furthermore, the emergence of human monkeypox in Africa and its expanding environs poses a significant natural threat. Such occurrences would require therapeutic and prophylactic intervention with antivirals to minimize morbidity and mortality of exposed populations. Two orally-bioavailable antivirals are currently in clinical trials; namely CMX001, an ether-lipid analog of cidofovir with activity at the DNA replication stage and ST-246, a novel viral egress inhibitor. Both of these drugs have previously been evaluated in the ectromelia/mousepox system; however, the trigger for intervention was not linked to a disease biomarker or a specific marker of virus replication. In this study we used lethal, intranasal, ectromelia virus infections of C57BL/6 and hairless SKH1 mice to model human disease and evaluate exanthematous rash (rash) as an indicator to initiate antiviral treatment. We show that significant protection can be provided to C57BL/6 mice by CMX001 or ST-246 when therapy is initiated on day 6 post infection or earlier. We also show that significant protection can be provided to SKH1 mice treated with CMX001 at day 3 post infection or earlier, but this is four or more days before detection of rash (ST-246 not tested). Although in this model rash could not be used as a treatment trigger, viral DNA was detected in blood by day 4 post infection and in the oropharyngeal secretions (saliva) by day 2–3 post infection – thus providing robust and specific markers of virus replication for therapy initiation. These findings are discussed in the context of current respiratory challenge animal models in use for the evaluation of poxvirus antivirals.
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Affiliation(s)
- Scott Parker
- Department of Molecular Microbiology and Immunology, Saint Louis University School of Medicine, MO 63104, United States
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13
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Golden JW, Hooper JW. The strategic use of novel smallpox vaccines in the post-eradication world. Expert Rev Vaccines 2012; 10:1021-35. [PMID: 21806397 PMCID: PMC9491137 DOI: 10.1586/erv.11.46] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
We still face a threat of orthopoxviruses in the form of biological weapons and emerging zoonoses. Therefore, there is a need to maintain a comprehensive defense strategy to counter the low-probability, high-impact threat of smallpox, as well as the ongoing threat of naturally occurring orthopoxvirus disease. The currently licensed live-virus smallpox vaccine ACAM2000 is effective, but associated with serious and even life-threatening adverse events. The health threat posed by this vaccine, and other previously licensed vaccines, has prevented many first responders, and even many in the military, from receiving a vaccine against smallpox. At the same time, global immunity produced during the smallpox eradication campaign is waning. Here, we review novel subunit/component vaccines and how they might play roles in unconventional strategies to defend against emerging orthopoxvirus diseases throughout the world and against smallpox used as a weapon of mass destruction.
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Affiliation(s)
- Joseph W Golden
- Department of Molecular Virology, Virology Division, United States Army Medical Research Institute of Infectious Diseases, Fort Detrick, MD 21702, USA
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14
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Verreault D, Sivasubramani SK, Talton JD, Doyle LA, Reddy JD, Killeen SZ, Didier PJ, Marx PA, Roy CJ. Evaluation of inhaled cidofovir as postexposure prophylactic in an aerosol rabbitpox model. Antiviral Res 2012; 93:204-8. [PMID: 22146565 PMCID: PMC3505885 DOI: 10.1016/j.antiviral.2011.11.013] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/21/2011] [Revised: 11/18/2011] [Accepted: 11/22/2011] [Indexed: 11/16/2022]
Abstract
Smallpox is considered a biological threat based upon the possibility of deliberate reintroduction into the population, creating an urgent need for effective antivirals. The antiviral drug cidofovir (Cr) has shown to be effective against poxviruses, although route-specific nephrotoxicity has hampered its development for emergency post-exposure prophylaxis (PEP). In this study, we use a micronized dry powder formulation of pharmaceutical-grade Cr (NanoFOVIRTM; Nf) to treat rabbits exposed to aerosolized rabbitpox virus (RPXV) to further evaluate the effectiveness of direct drug delivery to the lung. Naïve rabbits were infected with RPXV by aerosol; three subsets received aerosolized Nf at 0.5, 1.0 or 1.75mg/kg daily for 3days post-exposure, positive and negative control groups received intravenous (IV) Cr treatments and no treatment, respectively. Nf groups showed an antiviral-dose associated survival of 50% (0.5mg/kg), 80% (1.0mg/kg) and 100% (1.75mg/kg). All animals (100%) from the IV-Cr treatment group and none (0%) from the untreated controls survived. Nf (1.75) protected rabbits from RPX at approximately 10% of the equivalent IV-Cr dose. A dose-related effect was observed in clinical development of RPX disease in Nf groups. Significant reduction of RPX-induced pathological changes was observed in Nf (1.75) and IV-Cr groups. Results suggest that Nf may be a viable antiviral for emergency post-exposure prophylaxis and should be evaluated in other models of poxviral disease.
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Affiliation(s)
- Daniel Verreault
- Divisions of Microbiology, Tulane National Primate Research Center, Covington, Louisiana USA
| | | | | | - Lara A. Doyle
- Veterinary Medicine, Tulane National Primate Research Center, Covington, Louisiana USA
| | | | - Stephanie Z. Killeen
- Divisions of Microbiology, Tulane National Primate Research Center, Covington, Louisiana USA
| | | | | | - Chad J. Roy
- Divisions of Microbiology, Tulane National Primate Research Center, Covington, Louisiana USA
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15
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Denzler KL, Rice AD, MacNeill AL, Fukushima N, Lindsey SF, Wallace G, Burrage AM, Smith AJ, Manning BR, Swetnam DM, Gray SA, Moyer RW, Jacobs BL. The NYCBH vaccinia virus deleted for the innate immune evasion gene, E3L, protects rabbits against lethal challenge by rabbitpox virus. Vaccine 2011; 29:7659-69. [PMID: 21840358 PMCID: PMC3190037 DOI: 10.1016/j.vaccine.2011.07.140] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/14/2011] [Revised: 07/28/2011] [Accepted: 07/31/2011] [Indexed: 11/29/2022]
Abstract
Vaccinia virus deleted for the innate immune evasion gene, E3L, has been shown to be highly attenuated and yet induces a protective immune response against challenge by homologous virus in a mouse model. In this manuscript the NYCBH vaccinia virus vaccine strain was compared to NYCBH vaccinia virus deleted for E3L (NYCBHΔE3L) in a rabbitpox virus (RPV) challenge model. Upon scarification, both vaccines produced a desired skin lesion, although the lesion produced by NYCBHΔE3L was smaller. Both vaccines fully protected rabbits against lethal challenge by escalating doses of RPV, from 10LD(50) to 1000LD(50). A single dose of NYCBHΔE3L protected rabbits from weight loss, fever, and clinical symptoms following the lowest dose challenge of 10LD(50), however it allowed a moderate level of RPV replication at the challenge site, some spread to external skin and mucosal surfaces, and increased numbers of secondary lesions as compared to vaccination with NYCBH. Alternately, two doses of NYCBHΔE3L fully protected rabbits from weight loss, fever, and clinical symptoms, following challenge with 100-1000LD(50) RPV, and it prevented development of secondary lesions similar to protection seen with NYCBH. Finally, vaccination with either one or two doses of NYCBHΔE3L resulted in similar neutralizing antibody titers following RPV challenge as compared to titers obtained by vaccination with NYCBH. These results support the efficacy of the attenuated NYCBHΔE3L in protection against an orthologous poxvirus challenge.
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Affiliation(s)
- Karen L Denzler
- Biodesign Institute, Arizona State University, Tempe, AZ 85287-5401, USA
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16
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Establishment of the black-tailed prairie dog (Cynomys ludovicianus) as a novel animal model for comparing smallpox vaccines administered preexposure in both high- and low-dose monkeypox virus challenges. J Virol 2011; 85:7683-98. [PMID: 21632764 DOI: 10.1128/jvi.02174-10] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
The 2003 monkeypox virus (MPXV) outbreak and subsequent laboratory studies demonstrated that the black-tailed prairie dog is susceptible to MPXV infection and that the ensuing rash illness is similar to human systemic orthopoxvirus (OPXV) infection, including a 7- to 9-day incubation period and, likely, in some cases a respiratory route of infection; these features distinguish this model from others. The need for safe and efficacious vaccines for OPVX in areas where it is endemic or epidemic is important to protect an increasingly OPXV-naïve population. In this study, we tested current and investigational smallpox vaccines for safety, induction of anti-OPXV antibodies, and protection against mortality and morbidity in two MPXV challenges. None of the smallpox vaccines caused illness in this model, and all vaccinated animals showed anti-OPXV antibody responses and neutralizing antibody. We tested vaccine efficacy by challenging the animals with 10(5) or 10(6) PFU Congo Basin MPXV 30 days postvaccination and evaluating morbidity and mortality. Our results demonstrated that vaccination with either Dryvax or Acambis2000 protected the animals from death with no rash illness. Vaccination with IMVAMUNE also protected the animals from death, albeit with (modified) rash illness. Based on the results of this study, we believe prairie dogs offer a novel and potentially useful small animal model for the safety and efficacy testing of smallpox vaccines in pre- and postexposure vaccine testing, which is important for public health planning.
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17
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Rice AD, Adams MM, Lampert B, Foster S, Lanier R, Robertson A, Painter G, Moyer RW. Efficacy of CMX001 as a prophylactic and presymptomatic antiviral agent in New Zealand white rabbits infected with rabbitpox virus, a model for orthopoxvirus infections of humans. Viruses 2011; 3:63-82. [PMID: 21369346 PMCID: PMC3045966 DOI: 10.3390/v3020063] [Citation(s) in RCA: 38] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/23/2010] [Accepted: 01/04/2011] [Indexed: 01/24/2023] Open
Abstract
CMX001, a lipophilic nucleotide analog formed by covalently linking 3-(hexdecyloxy)propan-1-ol to cidofovir (CDV), is being developed as a treatment for smallpox. CMX001 has dramatically increased potency versus CDV against all dsDNA viruses and, in contrast to CDV, is orally available and has shown no evidence of nephrotoxicity in healthy volunteers or severely ill transplant patients to date. Although smallpox has been eliminated from the environment, treatments are urgently being sought due to the risk of smallpox being used as a bioterrorism agent and for monkeypox virus, a zoonotic disease of Africa, and adverse reactions to smallpox virus vaccinations. In the absence of human cases of smallpox, new treatments must be tested for efficacy in animal models. Here we first review and discuss the rabbitpox virus (RPV) infection of New Zealand White rabbits as a model for smallpox to test the efficacy of CMX001 as a prophylactic and early disease antiviral. Our results should also be applicable to monkeypox virus infections and for treatment of adverse reactions to smallpox vaccination.
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Affiliation(s)
- Amanda D. Rice
- Department of Molecular Genetics and Microbiology, University of Florida, 1600 SW Archer Rd, Gainesville, FL 32610, USA; E-Mails: (A.D.R.); (M.M.A.)
| | - Mathew M. Adams
- Department of Molecular Genetics and Microbiology, University of Florida, 1600 SW Archer Rd, Gainesville, FL 32610, USA; E-Mails: (A.D.R.); (M.M.A.)
| | - Bernhard Lampert
- Chimerix, Inc., 2505 Meridian Parkway Suite, 340 Durham, NC 27713, USA; E-Mails: (B.L.); (S.F.); (R.L.); (A.R.); (G.P.)
| | - Scott Foster
- Chimerix, Inc., 2505 Meridian Parkway Suite, 340 Durham, NC 27713, USA; E-Mails: (B.L.); (S.F.); (R.L.); (A.R.); (G.P.)
| | - Randall Lanier
- Chimerix, Inc., 2505 Meridian Parkway Suite, 340 Durham, NC 27713, USA; E-Mails: (B.L.); (S.F.); (R.L.); (A.R.); (G.P.)
| | - Alice Robertson
- Chimerix, Inc., 2505 Meridian Parkway Suite, 340 Durham, NC 27713, USA; E-Mails: (B.L.); (S.F.); (R.L.); (A.R.); (G.P.)
| | - George Painter
- Chimerix, Inc., 2505 Meridian Parkway Suite, 340 Durham, NC 27713, USA; E-Mails: (B.L.); (S.F.); (R.L.); (A.R.); (G.P.)
| | - Richard W. Moyer
- Department of Molecular Genetics and Microbiology, University of Florida, 1600 SW Archer Rd, Gainesville, FL 32610, USA; E-Mails: (A.D.R.); (M.M.A.)
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18
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Rice AD, Adams MM, Wallace G, Burrage AM, Lindsey SF, Smith AJ, Swetnam D, Manning BR, Gray SA, Lampert B, Foster S, Lanier R, Robertson A, Painter G, Moyer RW. Efficacy of CMX001 as a post exposure antiviral in New Zealand White rabbits infected with rabbitpox virus, a model for orthopoxvirus infections of humans. Viruses 2011; 3:47-62. [PMID: 21373379 PMCID: PMC3046869 DOI: 10.3390/v3010047] [Citation(s) in RCA: 35] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/01/2010] [Revised: 01/04/2011] [Accepted: 01/05/2011] [Indexed: 11/30/2022] Open
Abstract
CMX001, a lipophilic nucleotide analog formed by covalently linking 3-(hexdecyloxy)propan-1-ol to cidofovir (CDV), is being developed as a treatment for smallpox. In the absence of human cases of smallpox, new treatments must be tested for efficacy in animal models. Previously, we demonstrated the efficacy of CMX001 in protecting New Zealand White rabbits from mortality following intradermal infection with rabbitpox virus as a model for smallpox, monkeypox and for treatment of adverse reactions to smallpox vaccination. Here we extend these studies by exploring different dosing regimens and performing randomized, blinded, placebo-controlled studies. In addition, because rabbitpox virus can be transmitted via naturally generated aerosols (animal to animal transmission), we report on studies to test the efficacy of CMX001 in protecting rabbits from lethal rabbitpox virus disease when infection occurs by animal to animal transmission. In all cases, CMX001 treatment was initiated at the onset of observable lesions in the ears to model the use of CMX001 as a treatment for symptomatic smallpox. The results demonstrate that CMX001 is an effective treatment for symptomatic rabbitpox virus infection. The rabbitpox model has key similarities to human smallpox including an incubation period, generalized systemic disease, the occurrence of lesions which may be used as a trigger for initiating therapy, and natural animal to animal spread, making it an appropriate model.
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Affiliation(s)
- Amanda D. Rice
- Department of Molecular Genetics and Microbiology, University of Florida, 1600 SW Archer Rd, Gainesville, FL 32610, USA; E-Mails: (A.D.R.); (M.M.A.); (G.W.); (A.M.B.); (S.F.L.); (A.J.S.); (D.S.); (B.R.M.); (S.A.G.)
| | - Mathew M. Adams
- Department of Molecular Genetics and Microbiology, University of Florida, 1600 SW Archer Rd, Gainesville, FL 32610, USA; E-Mails: (A.D.R.); (M.M.A.); (G.W.); (A.M.B.); (S.F.L.); (A.J.S.); (D.S.); (B.R.M.); (S.A.G.)
| | - Greg Wallace
- Department of Molecular Genetics and Microbiology, University of Florida, 1600 SW Archer Rd, Gainesville, FL 32610, USA; E-Mails: (A.D.R.); (M.M.A.); (G.W.); (A.M.B.); (S.F.L.); (A.J.S.); (D.S.); (B.R.M.); (S.A.G.)
| | - Andrew M. Burrage
- Department of Molecular Genetics and Microbiology, University of Florida, 1600 SW Archer Rd, Gainesville, FL 32610, USA; E-Mails: (A.D.R.); (M.M.A.); (G.W.); (A.M.B.); (S.F.L.); (A.J.S.); (D.S.); (B.R.M.); (S.A.G.)
| | - Scott F. Lindsey
- Department of Molecular Genetics and Microbiology, University of Florida, 1600 SW Archer Rd, Gainesville, FL 32610, USA; E-Mails: (A.D.R.); (M.M.A.); (G.W.); (A.M.B.); (S.F.L.); (A.J.S.); (D.S.); (B.R.M.); (S.A.G.)
| | - Andrew J. Smith
- Department of Molecular Genetics and Microbiology, University of Florida, 1600 SW Archer Rd, Gainesville, FL 32610, USA; E-Mails: (A.D.R.); (M.M.A.); (G.W.); (A.M.B.); (S.F.L.); (A.J.S.); (D.S.); (B.R.M.); (S.A.G.)
| | - Daniele Swetnam
- Department of Molecular Genetics and Microbiology, University of Florida, 1600 SW Archer Rd, Gainesville, FL 32610, USA; E-Mails: (A.D.R.); (M.M.A.); (G.W.); (A.M.B.); (S.F.L.); (A.J.S.); (D.S.); (B.R.M.); (S.A.G.)
| | - Brandi R. Manning
- Department of Molecular Genetics and Microbiology, University of Florida, 1600 SW Archer Rd, Gainesville, FL 32610, USA; E-Mails: (A.D.R.); (M.M.A.); (G.W.); (A.M.B.); (S.F.L.); (A.J.S.); (D.S.); (B.R.M.); (S.A.G.)
| | - Stacey A. Gray
- Department of Molecular Genetics and Microbiology, University of Florida, 1600 SW Archer Rd, Gainesville, FL 32610, USA; E-Mails: (A.D.R.); (M.M.A.); (G.W.); (A.M.B.); (S.F.L.); (A.J.S.); (D.S.); (B.R.M.); (S.A.G.)
| | - Bernhard Lampert
- Chimerix, Inc., 2505 Meridian Parkway Suite, 340 Durham, NC 27713, USA; E-Mails: (B.L.); (S.F.); (R.L.); (A.R.); (G.P.)
| | - Scott Foster
- Chimerix, Inc., 2505 Meridian Parkway Suite, 340 Durham, NC 27713, USA; E-Mails: (B.L.); (S.F.); (R.L.); (A.R.); (G.P.)
| | - Randall Lanier
- Chimerix, Inc., 2505 Meridian Parkway Suite, 340 Durham, NC 27713, USA; E-Mails: (B.L.); (S.F.); (R.L.); (A.R.); (G.P.)
| | - Alice Robertson
- Chimerix, Inc., 2505 Meridian Parkway Suite, 340 Durham, NC 27713, USA; E-Mails: (B.L.); (S.F.); (R.L.); (A.R.); (G.P.)
| | - George Painter
- Chimerix, Inc., 2505 Meridian Parkway Suite, 340 Durham, NC 27713, USA; E-Mails: (B.L.); (S.F.); (R.L.); (A.R.); (G.P.)
| | - Richard W. Moyer
- Department of Molecular Genetics and Microbiology, University of Florida, 1600 SW Archer Rd, Gainesville, FL 32610, USA; E-Mails: (A.D.R.); (M.M.A.); (G.W.); (A.M.B.); (S.F.L.); (A.J.S.); (D.S.); (B.R.M.); (S.A.G.)
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Abstract
Smallpox is a human disease caused by infection with variola virus, a member of the genus Orthopoxvirus. Although smallpox has been eradicated, concern that it might be reintroduced through bioterrorism has therefore led to intensive efforts to develop new vaccines and antiviral drugs against this disease. Because these vaccines and therapeutics cannot be tested in human trials, it is necessary to test such medical countermeasures in different animal models. Although several orthopoxviruses cause disease in laboratory animals, only rabbitpox virus (RPXV) infection of rabbits shows patterns of natural airborne transmission similar to smallpox. Studies have shown that a smallpox-like disease can be produced in rabbits in a controlled fashion through exposure to a small-particle RPXV aerosol, and rabbitpox spreads from animal to animal by the airborne route in a laboratory setting. This model can therefore be utilized to test drugs and vaccines against variola virus and other aerosolized orthopoxviruses.
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Affiliation(s)
- Aysegul Nalca
- Center for Aerobiological Sciences, US Army Medical Research Institute of Infectious Diseases, Fort Detrick, Maryland, USA.
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20
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Roy CJ, Voss TG. Use of the Aerosol Rabbitpox Virus Model for Evaluation of Anti-Poxvirus Agents. Viruses 2010; 2:2096-2107. [PMID: 20953322 PMCID: PMC2954426 DOI: 10.3390/v2092096] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022] Open
Abstract
Smallpox is an acute disease caused by infection with variola virus that has had historic effects on the human population due to its virulence and infectivity. Because variola remains a threat to humans, the discovery and development of novel pox therapeutics and vaccines has been an area of intense focus. As variola is a uniquely human virus lacking a robust animal model, the development of rational therapeutic or vaccine approaches for variola requires the use of model systems that reflect the clinical aspects of human infection. Many laboratory animal models of poxviral disease have been developed over the years to study host response and to evaluate new therapeutics and vaccines for the treatment or prevention of human smallpox. Rabbitpox (rabbitpox virus infection in rabbits) is a severe and often lethal infection that has been identified as an ideal disease model for the study of poxviruses in a non-rodent species. The aerosol infection model (aerosolized rabbitpox infection) embodies many of the desired aspects of the disease syndrome that involves the respiratory system and thus may serve as an appropriate model for evaluation of antivirals under development for the therapeutic treatment of human smallpox. In this review we summarize the aerosol model of rabbitpox, discuss the development efforts that have thus far used this model for antiviral testing, and comment on the prospects for its use in future evaluations requiring a poxviral model with a focus on respiratory infection.
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Affiliation(s)
- Chad J. Roy
- Infectious Disease Aerobiology, Microbiology Division, Tulane National Primate Research Center, 18703 Three Rivers Road, Covington, Louisiana, USA
- Department of Microbiology & Immunology, Tulane University School of Medicine, New Orleans, Louisiana, USA; E-Mail:
- Author to whom correspondence should be addressed; E-Mail: ; Tel.: +1-985-871-6417; Fax: +1-985-871-6260
| | - Thomas G. Voss
- Department of Microbiology & Immunology, Tulane University School of Medicine, New Orleans, Louisiana, USA; E-Mail:
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21
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Nalca A, Livingston VA, Garza NL, Zumbrun EE, Frick OM, Chapman JL, Hartings JM. Experimental infection of cynomolgus macaques (Macaca fascicularis) with aerosolized monkeypox virus. PLoS One 2010; 5:e12880. [PMID: 20862223 PMCID: PMC2942837 DOI: 10.1371/journal.pone.0012880] [Citation(s) in RCA: 55] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/24/2010] [Accepted: 08/11/2010] [Indexed: 11/18/2022] Open
Abstract
Monkeypox virus (MPXV) infection in humans results in clinical symptoms very similar to ordinary smallpox. Aerosol is a route of secondary transmission for monkeypox, and a primary route of smallpox transmission in humans. Therefore, an animal model for aerosol exposure to MPXV is needed to test medical countermeasures. To characterize the pathogenesis in cynomolgus macaques (Macaca fascicularis), groups of macaques were exposed to four different doses of aerosolized MPXV. Blood was collected the day before, and every other day after exposure and assessed for complete blood count (CBC), clinical chemistry analysis, and quantitative PCR. Macaques showed mild anorexia, depression, and fever on day 6 post-exposure. Lymphadenopathy, which differentiates monkeypox from smallpox, was observed in exposed macaques around day 6 post-exposure. CBC and clinical chemistries showed abnormalities similar to human monkeypox cases. Whole blood and throat swab viral loads peaked around day 10, and in survivors, gradually decreased until day 28 post-exposure. Survival was not dose dependent. As such, doses of 4 × 10(4) PFU, 1 × 10(5) PFU, or 1 × 10(6) PFU resulted in lethality for 70% of the animals, whereas a dose of 4 × 10(5) PFU resulted in 85% lethality. Overall, cynomolgus macaques exposed to aerosolized MPXV develop a clinical disease that resembles that of human monkeypox. These findings provide a strong foundation for the use of aerosolized MPXV exposure of cynomolgus macaques as an animal model to test medical countermeasures against orthopoxviruses.
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Affiliation(s)
- Aysegul Nalca
- Center for Aerobiological Sciences, United States Army Medical Research Institute of Infectious Diseases, Fort Detrick, Maryland, USA.
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22
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Meseda CA, Weir JP. Third-generation smallpox vaccines: challenges in the absence of clinical smallpox. Future Microbiol 2010; 5:1367-82. [DOI: 10.2217/fmb.10.98] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
Smallpox, a disease caused by variola virus, is estimated to have killed hundreds of millions to billions of people before it was certified as eradicated in 1980. However, there has been renewed interest in smallpox vaccine development due in part to zoonotic poxvirus infections and the possibility of a re-emergence of smallpox, as well as the fact that first-generation smallpox vaccines are associated with relatively rare, but severe, adverse reactions in some vaccinees. An understanding of the immune mechanisms of vaccine protection and the use of suitable animal models for vaccine efficacy assessment are paramount to the development of safer and effective smallpox vaccines. This article focuses on studies aimed at understanding the immune responses elicited by vaccinia virus and the various animal models that can be used to evaluate smallpox vaccine efficacy. Harnessing this information is necessary to assess the effectiveness and potential usefulness of new-generation smallpox vaccines.
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Affiliation(s)
| | - Jerry P Weir
- Division of Viral Products, Center for Biologics Evaluation & Research, USFDA, 1401 Rockville Pike, HFM-457, Rockville, MD 20852, USA
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Chapman JL, Nichols DK, Martinez MJ, Raymond JW. Animal models of orthopoxvirus infection. Vet Pathol 2010; 47:852-70. [PMID: 20682806 DOI: 10.1177/0300985810378649] [Citation(s) in RCA: 89] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
Smallpox was one of the most devastating diseases known to humanity. Although smallpox was eradicated through a historically successful vaccination campaign, there is concern in the global community that either Variola virus (VARV), the causative agent of smallpox, or another species of Orthopoxvirus could be used as agents of bioterrorism. Therefore, development of countermeasures to Orthopoxvirus infection is a crucial focus in biodefense research, and these efforts rely on the use of various animal models. Smallpox typically presented as a generalized pustular rash with 30 to 40% mortality, and although smallpox-like syndromes can be induced in cynomolgus macaques with VARV, research with this virus is highly restricted; therefore, animal models with other orthopoxviruses have been investigated. Monkeypox virus causes a generalized vesiculopustular rash in rhesus and cynomolgus macaques and induces fatal systemic disease in several rodent species. Ectromelia virus has been extensively studied in mice as a model of orthopoxviral infection in its natural host. Intranasal inoculation of mice with some strains of vaccinia virus produces fatal bronchopneumonia, as does aerosol or intranasal inoculation of mice with cowpox virus. Rabbitpox virus causes pneumonia and fatal systemic infections in rabbits and can be naturally transmitted between rabbits by an aerosol route similar to that of VARV in humans. No single animal model recapitulates all known aspects of human Orthopoxvirus infections, and each model has its advantages and disadvantages. This article provides a brief review of the Orthopoxvirus diseases of humans and the key pathologic features of animal models of Orthopoxvirus infections.
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Affiliation(s)
- J L Chapman
- DVM, Major, US Army, US Army Medical Research Institute of Infectious Diseases, 1425 Porter Street, Frederick, MD 21702, USA.
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Lauterbach H, Kassub R, Pätzold J, Körner J, Brückel M, Verschoor A, Chaplin P, Suter M, Hochrein H. Immune requirements of post-exposure immunization with modified vaccinia Ankara of lethally infected mice. PLoS One 2010; 5:e9659. [PMID: 20300179 PMCID: PMC2836377 DOI: 10.1371/journal.pone.0009659] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/15/2009] [Accepted: 02/19/2010] [Indexed: 11/20/2022] Open
Abstract
Current prophylactic vaccines work via the induction of B and T cell mediated memory that effectively control further replication of the pathogen after entry. In the case of therapeutic or post-exposure vaccinations the situation is far more complex, because the pathogen has time to establish itself in the host, start producing immune-inhibitory molecules and spread into distant organs. So far it is unclear which immune parameters have to be activated in order to thwart an existing lethal infection. Using the mousepox model, we investigated the immunological mechanisms responsible for a successful post-exposure immunization with modified vaccinia Ankara (MVA). In contrast to intranasal application of MVA, we found that intravenous immunization fully protected mice infected with ectromelia virus (ECTV) when applied three days after infection. Intravenous MVA immunization induced strong innate and adaptive immune responses in lethally infected mice. By using various gene-targeted and transgenic mouse strains we show that NK cells, CD4 T cells, CD8 T cells and antibodies are essential for the clearance of ECTV after post-exposure immunization. Post-exposure immunization with MVA is an effective measure in a murine model of human smallpox. MVA activates innate and adaptive immune parameters and only a combination thereof is able to purge ECTV from its host. These data not only provide a basis for therapeutic vaccinations in the case of the deliberate release of pathogenic poxviruses but possibly also for the treatment of chronic infections and cancer.
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