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Larson L, Miller L, Margiasso M, Piontkowski M, Tremblay D, Dykstra S, Miller J, Slagter BJ, Champ D, Keil D, Patel M, Wasmoen T. Early administration of canine parvovirus monoclonal antibody prevented mortality after experimental challenge. J Am Vet Med Assoc 2024; 262:506-512. [PMID: 38295522 DOI: 10.2460/javma.23.09.0541] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/03/2023] [Accepted: 12/29/2023] [Indexed: 02/02/2024]
Abstract
OBJECTIVE To evaluate the effectiveness of canine parvovirus monoclonal antibody (CPMA) as a treatment against canine parvovirus (CPV-2)-induced mortality and to support USDA product licensure. ANIMALS 28 purpose-bred Beagle dogs aged 8 weeks were randomized to the treated (n = 21) or control (7) group. METHODS Dogs were challenged intranasally with 104.2 TCID50 virulent CPV-2b on Day 0 and monitored for 14 days for fecal viral shed and clinical disease. All dogs began shedding CPV-2 on Day 4 and were treated intravenously with a single dose of either CPMA (0.2 mL/kg) or saline (equal volume). No additional treatments were given to either group. Feces and sera were collected for quantitative analysis of fecal viral shed (hemagglutination) and antibody responses (hemagglutination inhibition and dot-blot ELISA), respectively. Dogs were monitored twice daily for parameters including lymphopenia, fever, vomiting, abnormal feces, inappetence, and lethargy. Humane endpoints triggered euthanasia by a veterinarian masked to treatment groups. The primary outcome variable was prevention of mortality as compared to controls. RESULTS Mortality was prevented in all CPMA-treated dogs compared to 57% mortality in the control group (P = .0017, Fisher exact test). Canine parvovirus monoclonal antibody-treated dogs also experienced less severe and/or shorter durations of diarrhea, fever, vomiting, CPV-2 shedding in feces, and lymphopenia. Both groups showed similar immunoglobulin M responses as measured by semiquantitative analysis. CLINICAL RELEVANCE Intravenous administration of CPMA can effectively improve clinical outcome when administered early in CPV-2 disease. Canine parvovirus monoclonal antibody treatment after proven infection does not interfere with adaptive immunity.
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Affiliation(s)
- Laurie Larson
- 1School of Veterinary Medicine, University of Wisconsin-Madison, Madison, WI
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Tegegne D, Tsegaye G, Faustini G, Franzo G. First genetic detection and characterization of canine parvovirus type 2 (Carnivore protoparvovirus 1) in southwestern Ethiopia. Vet Res Commun 2023; 47:975-980. [PMID: 36322244 DOI: 10.1007/s11259-022-10027-4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/25/2022] [Accepted: 10/19/2022] [Indexed: 05/25/2023]
Abstract
The species Carnivore protoparvovirus 1 includes viruses, e.g. canine parvovirus (CPV-2) and feline panleukopenia virus (FPV), which are among the most relevant for pets, causing extremely severe clinical signs and high fatality rate in dogs and cats. Moreover, a broad range of wild hosts, including endangered ones, were proven to be susceptible. Currently, no data on CPV-2 molecular epidemiology and strain characterization are available in Ethiopia, also considering the frequent contacts between domestic and wild populations. In the present study, a molecular epidemiology survey was performed on 92 fecal samples collected from domestic (n = 84) and stray (n = 8) dogs in southwestern Ethiopia in 2021. Approximately, 10% of the samples tested positive and the complete VP2 sequences of 5 strains were obtained, classified within the CPV-2a (n = 1) and CPV-2c (n = 4) antigenic variants. In most instances, the closest genetic relatives were strains of Chinese origin, which is fully compatible with the intense relationships that have been developing between the two countries, involving human being travels and their pets as well. Considering the clinical relevance of this infection and the risk it poses to local domestic and wild carnivore populations, especially endangered ones, much stronger monitoring and surveillance activity on foreign incoming animals should be performed. More strict constraints on animal introduction, e.g. compulsory vaccination, should also be considered.
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Affiliation(s)
- Dechassa Tegegne
- School of Veterinary Medicine, Jimma University College of Agriculture and Veterinary Medicine, P.O. Box 307, Jimma, Ethiopia
| | - Girma Tsegaye
- School of Veterinary Medicine, Jimma University College of Agriculture and Veterinary Medicine, P.O. Box 307, Jimma, Ethiopia
| | - Giulia Faustini
- Department of Animal Medicine, Production and Health (MAPS), University of Padua, Viale Dell'Università 16, 35020, Legnaro, PD, Italy
| | - Giovanni Franzo
- Department of Animal Medicine, Production and Health (MAPS), University of Padua, Viale Dell'Università 16, 35020, Legnaro, PD, Italy.
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Shao L, Shen W, Wang S, Qiu J. Recent Advances in Molecular Biology of Human Bocavirus 1 and Its Applications. Front Microbiol 2021; 12:696604. [PMID: 34220786 PMCID: PMC8242256 DOI: 10.3389/fmicb.2021.696604] [Citation(s) in RCA: 14] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/17/2021] [Accepted: 05/12/2021] [Indexed: 11/25/2022] Open
Abstract
Human bocavirus 1 (HBoV1) was discovered in human nasopharyngeal specimens in 2005. It is an autonomous human parvovirus and causes acute respiratory tract infections in young children. HBoV1 infects well differentiated or polarized human airway epithelial cells in vitro. Unique among all parvoviruses, HBoV1 expresses 6 non-structural proteins, NS1, NS1-70, NS2, NS3, NS4, and NP1, and a viral non-coding RNA (BocaSR), and three structural proteins VP1, VP2, and VP3. The BocaSR is the first identified RNA polymerase III (Pol III) transcribed viral non-coding RNA in small DNA viruses. It plays an important role in regulation of viral gene expression and a direct role in viral DNA replication in the nucleus. HBoV1 genome replication in the polarized/non-dividing airway epithelial cells depends on the DNA damage and DNA repair pathways and involves error-free Y-family DNA repair DNA polymerase (Pol) η and Pol κ. Importantly, HBoV1 is a helper virus for the replication of dependoparvovirus, adeno-associated virus (AAV), in polarized human airway epithelial cells, and HBoV1 gene products support wild-type AAV replication and recombinant AAV (rAAV) production in human embryonic kidney (HEK) 293 cells. More importantly, the HBoV1 capsid is able to pseudopackage an rAAV2 or rHBoV1 genome, producing the rAAV2/HBoV1 or rHBoV1 vector. The HBoV1 capsid based rAAV vector has a high tropism for human airway epithelia. A deeper understanding in HBoV1 replication and gene expression will help find a better way to produce the rAAV vector and to increase the efficacy of gene delivery using the rAAV2/HBoV1 or rHBoV1 vector, in particular, to human airways. This review summarizes the recent advances in gene expression and replication of HBoV1, as well as the use of HBoV1 as a parvoviral vector for gene delivery.
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Affiliation(s)
- Liting Shao
- Beijing Institute of Radiation Medicine, Beijing, China
| | - Weiran Shen
- Department of Microbiology, Molecular Genetics and Immunology, University of Kansas Medical Center, Kansas City, KS, United States
| | - Shengqi Wang
- Beijing Institute of Radiation Medicine, Beijing, China
| | - Jianming Qiu
- Department of Microbiology, Molecular Genetics and Immunology, University of Kansas Medical Center, Kansas City, KS, United States
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Molecular Epidemiological Survey of Canine Parvovirus Circulating in China from 2014 to 2019. PATHOGENS (BASEL, SWITZERLAND) 2021; 10:pathogens10050588. [PMID: 34064982 PMCID: PMC8150379 DOI: 10.3390/pathogens10050588] [Citation(s) in RCA: 17] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 03/24/2021] [Revised: 05/01/2021] [Accepted: 05/04/2021] [Indexed: 11/17/2022]
Abstract
The global distribution of canine parvovirus (CPV-2) derived from a closely related carnivore parvovirus poses a considerable threat to the dog population. The virus is continuously undergoing genetic evolution, giving rise to several variants. To investigate the prevalence of Chinese CPV-2 strains in recent years, a total of 30 CPV-2 strains were collected from 2018 to 2021 and the VP2 gene was sequenced and analyzed. Two variants, new CPV-2a (297Ala, 426Asn) and CPV-2c (426Glu), were identified. In contrast to previous reports, the CPV-2c variant has gained an epidemiological advantage over the new CPV-2a variant in China. To compensate for the relatively small sample size, 683 Chinese CPV-2 strains identified between 2014 and 2019 were retrieved from the GenBank database and previous publications, and analyses of these strains further supported our findings, which should be considered since the CPV-2c variant has been frequently associated with immune failure in adult dogs. VP2 protein sequence analysis revealed several amino acid substitutions, including Ala5Gly, Pro13Ser, Phe267Tyr, Tyr324Ile, Gln370Arg, Thr440Ala, and Lys570Arg. Phylogenetic analysis of full-length VP2 gene indicated a close relationship between Chinese strains and other Asian strains, suggesting mutual transmission between Asian countries. Furthermore, intercontinental transmission is a cause for concern. Surprisingly, two feline panleukopenia virus (FPV) strains with the Ile101Thr mutation in the VP2 protein were identified in canine fecal samples; FPV has been considered incapable of infecting dogs. This study clarified the epidemic characteristics of Chinese CPV-2 strains detected between 2014 and 2019, offering a reference for epidemic control. In addition, the detection of FPV in canine samples may provide information for future studies on the evolution of carnivore parvoviruses.
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Parvovirus B19 Uncoating Occurs in the Cytoplasm without Capsid Disassembly and It Is Facilitated by Depletion of Capsid-Associated Divalent Cations. Viruses 2019; 11:v11050430. [PMID: 31083301 PMCID: PMC6563316 DOI: 10.3390/v11050430] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/17/2019] [Revised: 05/07/2019] [Accepted: 05/09/2019] [Indexed: 12/19/2022] Open
Abstract
Human parvovirus B19 (B19V) traffics to the cell nucleus where it delivers the genome for replication. The intracellular compartment where uncoating takes place, the required capsid structural rearrangements and the cellular factors involved remain unknown. We explored conditions that trigger uncoating in vitro and found that prolonged exposure of capsids to chelating agents or to buffers with chelating properties induced a structural rearrangement at 4 °C resulting in capsids with lower density. These lighter particles remained intact but were unstable and short exposure to 37 °C or to a freeze-thaw cycle was sufficient to trigger DNA externalization without capsid disassembly. The rearrangement was not observed in the absence of chelating activity or in the presence of MgCl2 or CaCl2, suggesting that depletion of capsid-associated divalent cations facilitates uncoating. The presence of assembled capsids with externalized DNA was also detected during B19V entry in UT7/Epo cells. Following endosomal escape and prior to nuclear entry, a significant proportion of the incoming capsids rearranged and externalized the viral genome without capsid disassembly. The incoming capsids with accessible genomes accumulated in the nuclear fraction, a process that was prevented when endosomal escape or dynein function was disrupted. In their uncoated conformation, capsids immunoprecipitated from cytoplasmic or from nuclear fractions supported in vitro complementary-strand synthesis at 37 °C. This study reveals an uncoating strategy of B19V based on a limited capsid rearrangement prior to nuclear entry, a process that can be mimicked in vitro by depletion of divalent cations.
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Ros C, Bayat N, Wolfisberg R, Almendral JM. Protoparvovirus Cell Entry. Viruses 2017; 9:v9110313. [PMID: 29072600 PMCID: PMC5707520 DOI: 10.3390/v9110313] [Citation(s) in RCA: 28] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/09/2017] [Revised: 10/21/2017] [Accepted: 10/23/2017] [Indexed: 01/25/2023] Open
Abstract
The Protoparvovirus (PtPV) genus of the Parvoviridae family of viruses includes important animal pathogens and reference molecular models for the entire family. Some virus members of the PtPV genus have arisen as promising tools to treat tumoral processes, as they exhibit marked oncotropism and oncolytic activities while being nonpathogenic for humans. The PtPVs invade and replicate within the nucleus making extensive use of the transport, transcription and replication machineries of the host cells. In order to reach the nucleus, PtPVs need to cross over several intracellular barriers and traffic through different cell compartments, which limit their infection efficiency. In this review we summarize molecular interactions, capsid structural transitions and hijacking of cellular processes, by which the PtPVs enter and deliver their single-stranded DNA genome into the host cell nucleus. Understanding mechanisms that govern the complex PtPV entry will be instrumental in developing approaches to boost their anticancer therapeutic potential and improving their safety profile.
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Affiliation(s)
- Carlos Ros
- Department of Chemistry and Biochemistry, University of Bern, 3012 Bern, Switzerland.
| | - Nooshin Bayat
- Centro de Biología Molecular "Severo Ochoa", Consejo Superior de Investigaciones Científicas-Universidad Autónoma de Madrid, Cantoblanco, 28049 Madrid, Spain.
| | - Raphael Wolfisberg
- Copenhagen Hepatitis C Program (CO-HEP), Department of Infectious Diseases and Clinical Research Centre, Hvidovre Hospital and Department of Immunology and Microbiology, Faculty of Health and Medical Sciences, University of Copenhagen, 1165 Copenhagen, Denmark.
| | - José M Almendral
- Centro de Biología Molecular "Severo Ochoa", Consejo Superior de Investigaciones Científicas-Universidad Autónoma de Madrid, Cantoblanco, 28049 Madrid, Spain.
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Sehata G, Sato H, Yamanaka M, Takahashi T, Kainuma R, Igarashi T, Oshima S, Noro T, Oishi E. Substitutions at residues 300 and 389 of the VP2 capsid protein serve as the minimal determinant of attenuation for canine parvovirus vaccine strain 9985-46. J Gen Virol 2017; 98:2759-2770. [PMID: 28984228 DOI: 10.1099/jgv.0.000936] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023] Open
Abstract
Identifying molecular determinants of virulence attenuation in live attenuated canine parvovirus (CPV) vaccines is important for assuring their safety. To this end, we identified mutations in the attenuated CPV 9985-46 vaccine strain that arose during serial passage in Crandell-Rees feline kidney cells by comparison with the wild-type counterpart, as well as minimal determinants of the loss of virulence. Four amino acid substitutions (N93K, G300V, T389N and V562L) in VP2 of strain 9985-46 significantly restricted infection in canine A72 cells. Using an infectious molecular clone system, we constructed isogenic CPVs of the parental virulent 9985 strain carrying single or double mutations. We observed that only a single amino acid substitution in VP2, G300V or T389N, attenuated the virulent parental virus. Combinations of these mutations further attenuated CPV to a level comparable to that of 9985-46. Strains with G300V/T389N substitutions did not induce clinical symptoms in experimentally infected pups, and their ability to infect canine cells was highly restricted. We found that another G300V/V562L double mutation decreased affinity of the virus for canine cells, although its pathogenicity to dogs was maintained. These results indicate that mutation of residue 300, which plays a critical role in host tropism, is not sufficient for viral attenuation in vivo, and that attenuation of 9985-46 strain is defined by at least two mutations in residues 300 and 389 of the VP2 capsid protein. This finding is relevant for quality control of the vaccine and provides insight into the rational design of second-generation live attenuated vaccine candidates.
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Affiliation(s)
- Go Sehata
- Kyoto Biken Laboratories, Inc., 24-16 Makishima, Uji, Kyoto 611-0041, Japan
| | - Hiroaki Sato
- Kyoto Biken Laboratories, Inc., 24-16 Makishima, Uji, Kyoto 611-0041, Japan
| | - Morimasa Yamanaka
- Kyoto Biken Laboratories, Inc., 24-16 Makishima, Uji, Kyoto 611-0041, Japan
| | - Takuo Takahashi
- Kyoto Biken Laboratories, Inc., 24-16 Makishima, Uji, Kyoto 611-0041, Japan
| | - Risa Kainuma
- Kyoto Biken Laboratories, Inc., 24-16 Makishima, Uji, Kyoto 611-0041, Japan
| | - Tatsuhiko Igarashi
- Kyoto Biken Laboratories, Inc., 24-16 Makishima, Uji, Kyoto 611-0041, Japan
| | - Sho Oshima
- Kyoto Biken Laboratories, Inc., 24-16 Makishima, Uji, Kyoto 611-0041, Japan
| | - Taichi Noro
- Kyoto Biken Laboratories, Inc., 24-16 Makishima, Uji, Kyoto 611-0041, Japan
| | - Eiji Oishi
- Kyoto Biken Laboratories, Inc., 24-16 Makishima, Uji, Kyoto 611-0041, Japan
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Franzo G, Tucciarone CM, Cecchinato M, Drigo M. Canine parvovirus type 2 (CPV-2) and Feline panleukopenia virus (FPV) codon bias analysis reveals a progressive adaptation to the new niche after the host jump. Mol Phylogenet Evol 2017; 114:82-92. [PMID: 28603036 DOI: 10.1016/j.ympev.2017.05.019] [Citation(s) in RCA: 29] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/04/2017] [Revised: 05/01/2017] [Accepted: 05/21/2017] [Indexed: 10/19/2022]
Abstract
Based on virus dependence from host cell machinery, their codon usage is expected to show a strong relation with the host one. Even if this association has been stated, especially for bacteria viruses, the linkage is considered to be less consistent for more complex organisms and a codon bias adaptation after host jump has never been proven. Canine parvovirus type 2 (CPV-2) was selected as a model because it represents a well characterized case of host jump, originating from Feline panleukopenia virus (FPV). The current study demonstrates that the adaptation to specific tissue and host codon bias affected CPV-2 evolution. Remarkably, FPV and CPV-2 showed a higher closeness toward the codon bias of the tissues they display the higher tropism for. Moreover, after the host jump, a clear and significant trend was evidenced toward a reduction in the distance between CPV-2 and the dog codon bias over time. This evidence was not confirmed for FPV, suggesting that an equilibrium has been reached during the prolonged virus-host co-evolution. Additionally, the presence of an intermediate pattern displayed by some strains infecting wild species suggests that these could have facilitated the host switch also by acting on codon bias.
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Smith RH, Hallwirth CV, Westerman M, Hetherington NA, Tseng YS, Cecchini S, Virag T, Ziegler ML, Rogozin IB, Koonin EV, Agbandje-McKenna M, Kotin RM, Alexander IE. Germline viral "fossils" guide in silico reconstruction of a mid-Cenozoic era marsupial adeno-associated virus. Sci Rep 2016; 6:28965. [PMID: 27377618 PMCID: PMC4932596 DOI: 10.1038/srep28965] [Citation(s) in RCA: 29] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/23/2016] [Accepted: 06/07/2016] [Indexed: 12/21/2022] Open
Abstract
Germline endogenous viral elements (EVEs) genetically preserve viral nucleotide sequences useful to the study of viral evolution, gene mutation, and the phylogenetic relationships among host organisms. Here, we describe a lineage-specific, adeno-associated virus (AAV)-derived endogenous viral element (mAAV-EVE1) found within the germline of numerous closely related marsupial species. Molecular screening of a marsupial DNA panel indicated that mAAV-EVE1 occurs specifically within the marsupial suborder Macropodiformes (present-day kangaroos, wallabies, and related macropodoids), to the exclusion of other Diprotodontian lineages. Orthologous mAAV-EVE1 locus sequences from sixteen macropodoid species, representing a speciation history spanning an estimated 30 million years, facilitated compilation of an inferred ancestral sequence that recapitulates the genome of an ancient marsupial AAV that circulated among Australian metatherian fauna sometime during the late Eocene to early Oligocene. In silico gene reconstruction and molecular modelling indicate remarkable conservation of viral structure over a geologic timescale. Characterisation of AAV-EVE loci among disparate species affords insight into AAV evolution and, in the case of macropodoid species, may offer an additional genetic basis for assignment of phylogenetic relationships among the Macropodoidea. From an applied perspective, the identified AAV “fossils” provide novel capsid sequences for use in translational research and clinical applications.
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Affiliation(s)
- Richard H Smith
- Laboratory of Molecular Virology and Gene Therapy, National Heart, Lung and Blood Institute, Bethesda, Maryland, United States of America
| | - Claus V Hallwirth
- Gene Therapy Research Unit, Children's Medical Research Institute and The Children's Hospital at Westmead, Westmead, New South Wales, Australia
| | - Michael Westerman
- Department of Biochemistry and Genetics, La Trobe University, Bundoora, Victoria, Australia
| | - Nicola A Hetherington
- Gene Therapy Research Unit, Children's Medical Research Institute and The Children's Hospital at Westmead, Westmead, New South Wales, Australia
| | - Yu-Shan Tseng
- The McKnight Brain Institute, University of Florida, Gainesville, Florida, United States of America
| | - Sylvain Cecchini
- Laboratory of Molecular Virology and Gene Therapy, National Heart, Lung and Blood Institute, Bethesda, Maryland, United States of America
| | - Tamas Virag
- Laboratory of Molecular Virology and Gene Therapy, National Heart, Lung and Blood Institute, Bethesda, Maryland, United States of America
| | - Mona-Larissa Ziegler
- Gene Therapy Research Unit, Children's Medical Research Institute and The Children's Hospital at Westmead, Westmead, New South Wales, Australia
| | - Igor B Rogozin
- Evolutionary Genomics Research Group, National Center for Biotechnology Information, National Library of Medicine, National Institutes of Health, Bethesda, Maryland, United States of America
| | - Eugene V Koonin
- Evolutionary Genomics Research Group, National Center for Biotechnology Information, National Library of Medicine, National Institutes of Health, Bethesda, Maryland, United States of America
| | - Mavis Agbandje-McKenna
- The McKnight Brain Institute, University of Florida, Gainesville, Florida, United States of America
| | - Robert M Kotin
- Laboratory of Molecular Virology and Gene Therapy, National Heart, Lung and Blood Institute, Bethesda, Maryland, United States of America
| | - Ian E Alexander
- Gene Therapy Research Unit, Children's Medical Research Institute and The Children's Hospital at Westmead, Westmead, New South Wales, Australia.,The University of Sydney, Discipline of Paediatrics and Child Health, Westmead, New South Wales, Australia
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Abstract
DNA viruses undertake their replication within the cell nucleus, and therefore they must first deliver their genome into the nucleus of their host cells. Thus, trafficking across the nuclear envelope is at the basis of DNA virus infections. Nuclear transport of molecules with diameters up to 39 nm is a tightly regulated process that occurs through the nuclear pore complex (NPC). Due to the enormous diversity of virus size and structure, each virus has developed its own strategy for entering the nucleus of their host cells, with no two strategies alike. For example, baculoviruses target their DNA-containing capsid to the NPC and subsequently enter the nucleus intact, while the hepatitis B virus capsid crosses the NPC but disassembles at the nuclear side of the NPC. For other viruses such as herpes simplex virus and adenovirus, although both dock at the NPC, they have each developed a distinct mechanism for the subsequent delivery of their genome into the nucleus. Remarkably, other DNA viruses, such as parvoviruses and human papillomaviruses, access the nucleus through an NPC-independent mechanism. This review discusses our current understanding of the mechanisms used by DNA viruses to deliver their genome into the nucleus, and further presents the experimental evidence for such mechanisms.
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Affiliation(s)
- Nikta Fay
- Department of Zoology, University of British Columbia Vancouver, BC, Canada
| | - Nelly Panté
- Department of Zoology, University of British Columbia Vancouver, BC, Canada
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11
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Abstract
Attenuated, live viral vaccines have been extraordinarily successful in protecting against many diseases. The main drawbacks in their development and use have been reliance on an unpredictable method of attenuation and the potential for evolutionary reversion to high virulence. Methods of genetic engineering now provide many safer alternatives to live vaccines, so if live vaccines are to compete with these alternatives in the future, they must either have superior immunogenicity or they must be able to overcome these former disadvantages. Several live vaccine designs that were historically inaccessible are now feasible because of advances in genome synthesis. Some of those methods are addressed here, with an emphasis on whether they enable predictable levels of attenuation and whether they are stable against evolutionary reversion. These new designs overcome many of the former drawbacks and position live vaccines to be competitive with alternatives. Not only do new methods appear to retard evolutionary reversion enough to prevent vaccine-derived epidemics, but it may even be possible to permanently attenuate live vaccines that are transmissible but cannot evolve to higher virulence under prolonged adaptation.
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Affiliation(s)
- J J Bull
- Department of Integrative Biology, The University of Texas at Austin, Austin, TX 78712, USA; Institute for Cellular and Molecular Biology, The University of Texas at Austin, Austin, TX 78712, USA; Center for Computational Biology and Bioinformatics, The University of Texas at Austin, Austin, TX 78712, USA
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12
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Abstract
UNLABELLED Bovine parvovirus (BPV), the causative agent of respiratory and gastrointestinal disease in cows, is the type member of the Bocaparvovirus genus of the Parvoviridae family. Toward efforts to obtain a template for the development of vaccines and small-molecule inhibitors for this pathogen, the structure of the BPV capsid, assembled from the major capsid viral protein 2 (VP2), was determined using X-ray crystallography as well as cryo-electron microscopy and three-dimensional image reconstruction (cryo-reconstruction) to 3.2- and 8.8-Å resolutions, respectively. The VP2 region ordered in the crystal structure, from residues 39 to 536, conserves the parvoviral eight-stranded jellyroll motif and an αA helix. The BPV capsid displays common parvovirus features: a channel at and depressions surrounding the 5-fold axes and protrusions surrounding the 3-fold axes. However, rather than a depression centered at the 2-fold axes, a raised surface loop divides this feature in BPV. Additional observed density in the capsid interior in the cryo-reconstructed map, compared to the crystal structure, is interpreted as 10 additional N-terminal residues, residues 29 to 38, that radially extend the channel under the 5-fold axis, as observed for human bocavirus 1 (HBoV1). Surface loops of various lengths and conformations extend from the core jellyroll motif of VP2. These loops confer the unique surface topology of the BPV capsid, making it strikingly different from HBoV1 as well as the type members of other Parvovirinae genera for which structures have been determined. For the type members, regions structurally analogous to those decorating the BPV capsid surface serve as determinants of receptor recognition, tissue and host tropism, pathogenicity, and antigenicity. IMPORTANCE Bovine parvovirus (BPV), identified in the 1960s in diarrheic calves, is the type member of the Bocaparvovirus genus of the nonenveloped, single-stranded DNA (ssDNA) Parvoviridae family. The recent isolation of human bocaparvoviruses from children with severe respiratory and gastrointestinal infections has generated interest in understanding the life cycle and pathogenesis of these emerging viruses. We have determined the high-resolution structure of the BPV capsid assembled from its predominant capsid protein VP2, known to be involved in a myriad of functions during host cell entry, pathogenesis, and antigenicity for other members of the Parvovirinae. Our results show the conservation of the core secondary structural elements and the location of the N-terminal residues for the known bocaparvovirus capsid structures. However, surface loops with high variability in sequence and conformation give BPV a unique capsid surface topology. Similar analogous regions in other Parvovirinae type members are important as determinants of receptor recognition, tissue and host tropism, pathogenicity, and antigenicity.
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Truyen U, Parrish CR. Feline panleukopenia virus: its interesting evolution and current problems in immunoprophylaxis against a serious pathogen. Vet Microbiol 2013; 165:29-32. [PMID: 23561891 DOI: 10.1016/j.vetmic.2013.02.005] [Citation(s) in RCA: 33] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/04/2012] [Revised: 02/10/2013] [Accepted: 02/11/2013] [Indexed: 11/26/2022]
Abstract
Vaccination of cats against feline panleukopenia virus (FPV) has been a routine part of feline medicine for the past 40 or more years, and many of the same vaccines that were first developed in the 1960s are still in routine use today. However, there has been significant evolution of the virus in the last 40 years, in particular the emergence of canine parvovirus (CPV) in dogs in the late 1970s, which was a host range variant of the FPV-like virus, and the world-wide spread of the CPV-derived viruses since 1978. FPV and the various antigenic types of CPV have been isolated from cats, raccoons, and many different wild and captive carnivores. The consequences of these changes in the viral populations have not been investigated, and the effectiveness of the current vaccine protocols have not been reported. Here we review the recent findings about the evolution of the viruses in carnivores including cats, and describe a study that looks at the efficiency of vaccination of kittens using the standard protocols, which shows that many cats are not protected by those approaches.
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Affiliation(s)
- Uwe Truyen
- Institut für Tierhygiene und Öffentliches Veterinärwesen, Universität Leipzig, An den Tierkliniken 1, 04103 Leipzig, Germany.
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Networks of evolutionary interactions underlying the polyphyletic origin of ssDNA viruses. Curr Opin Virol 2013; 3:578-86. [PMID: 23850154 DOI: 10.1016/j.coviro.2013.06.010] [Citation(s) in RCA: 86] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/30/2013] [Revised: 06/13/2013] [Accepted: 06/17/2013] [Indexed: 11/22/2022]
Abstract
Viruses with single-stranded (ss) DNA genomes infect hosts from all three domains of life and are present in all imaginable environments. Many new ssDNA viruses have been recently isolated, including those infecting algae, fungi, insects and even archaea. In parallel, culture-independent metagenomic approaches have illuminated the tremendous genetic diversity of these viruses, yielding valuable insights into their evolution. Here, I integrate this knowledge to propose a scenario in which certain groups of ssDNA viruses (including Geminiviridae, Circoviridae, Parvoviridae and Microviridae) have originated from plasmids via acquisition of jelly-roll capsid protein genes from ssRNA viruses. This scenario places structurally related viruses with DNA and RNA genomes into an evolutionary continuum and highlights general evolutionary trends in the virosphere.
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15
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Moyer CL, Nemerow GR. Viral weapons of membrane destruction: variable modes of membrane penetration by non-enveloped viruses. Curr Opin Virol 2012; 1:44-9. [PMID: 21804909 DOI: 10.1016/j.coviro.2011.05.002] [Citation(s) in RCA: 48] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/03/2023]
Abstract
Significant progress has recently been obtained in our understanding of cellular entry by nonenveloped viruses (NEVs). A key step in the entry process involves the disruption or remodeling of the limiting cell membrane allowing the virus to gain access to the cellular replication machinery. Biochemical, genetic and structural data from diverse virus groups have shed light on the process of membrane penetration thereby revealing both the conservation and divergence of the mechanisms and principles governing this process. In general, membrane breach is achieved via the highly regulated spatiotemporal exposure of a virally encoded membrane lytic factor, resulting in the transfer of the viral genome or nucleocapsid into the cytosol.
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Affiliation(s)
- Crystal L Moyer
- Department of Immunology and Microbial Sciences, The Scripps Research Institute, La Jolla, CA 92037, USA
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16
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Abstract
The early steps of human parvovirus B19 (B19V) infection were investigated in UT7/Epo cells. B19V and its receptor globoside (Gb4Cer) associate with lipid rafts, predominantly of the noncaveolar type. Pharmacological disruption of the lipid rafts inhibited infection when the drug was added prior to virus attachment but not after virus uptake. B19V is internalized by clathrin-dependent endocytosis and spreads rapidly throughout the endocytic pathway, reaching the lysosomal compartment within minutes, where a substantial proportion is degraded. B19V did not permeabilize the endocytic vesicles, indicating a mechanism of endosomal escape without apparent membrane damage. Bafilomycin A(1) (BafA1) and NH(4)Cl, which raise endosomal pH, blocked the infection by preventing endosomal escape, resulting in a massive accumulation of capsids in the lysosomes. In contrast, in the presence of chloroquine (CQ), the transfer of incoming viruses from late endosomes to lysosomes was prevented; the viral DNA was not degraded; and the infection was boosted. In contrast to the findings for untreated or BafA1-treated cells, the viral DNA was progressively associated with the nucleus in CQ-treated cells, reaching a plateau by 3 h postinternalization, a time coinciding with the initiation of viral transcription. At this time, more than half of the total intracellular viral DNA was associated with the nucleus; however, the capsids remained extranuclear. Our studies provide the first insight into the early steps of B19V infection and reveal mechanisms involved in virus uptake, endocytic trafficking, and nuclear penetration.
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Impact of VP1-specific protein sequence motifs on adeno-associated virus type 2 intracellular trafficking and nuclear entry. J Virol 2012; 86:9163-74. [PMID: 22696661 DOI: 10.1128/jvi.00282-12] [Citation(s) in RCA: 63] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022] Open
Abstract
Adeno-associated virus type 2 (AAV2) has gained much interest as a gene delivery vector. A hallmark of AAV2-mediated gene transfer is an intracellular conformational change of the virus capsid, leading to the exposure of infection-relevant protein domains. These protein domains, which are located on the N-terminal portion of the structural proteins VP1 and VP2, include a catalytic phospholipase A(2) domain and three clusters of basic amino acids. We have identified additional protein sequence motifs located on the VP1/2 N terminus that also proved to be obligatory for virus infectivity. These motifs include signals that are known to be involved in protein interaction, endosomal sorting and signal transduction in eukaryotic cells. Among different AAV serotypes they are highly conserved and mutation of critical amino acids of the respective motifs led to a severe infection-deficient phenotype. In particular, mutation of a YXXQ-sequence motif significantly reduced accumulation of virus capsids around the nucleus in comparison to wild-type AAV2. Interestingly, intracellular trafficking of AAV2 was shown to be independent of PLA(2) activity. Moreover, mutation of three PDZ-binding motifs, which are located consecutively at the very tip of the VP1 N terminus, revealed a nuclear transport-defective phenotype, suggesting a role in nuclear uptake of the virus through an as-yet-unknown mechanism.
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18
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DiMattia MA, Nam HJ, Van Vliet K, Mitchell M, Bennett A, Gurda BL, McKenna R, Olson NH, Sinkovits RS, Potter M, Byrne BJ, Aslanidi G, Zolotukhin S, Muzyczka N, Baker TS, Agbandje-McKenna M. Structural insight into the unique properties of adeno-associated virus serotype 9. J Virol 2012; 86:6947-58. [PMID: 22496238 PMCID: PMC3393551 DOI: 10.1128/jvi.07232-11] [Citation(s) in RCA: 143] [Impact Index Per Article: 11.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/28/2011] [Accepted: 04/03/2012] [Indexed: 12/20/2022] Open
Abstract
Adeno-associated virus serotype 9 (AAV9) has enhanced capsid-associated tropism for cardiac muscle and the ability to cross the blood-brain barrier compared to other AAV serotypes. To help identify the structural features facilitating these properties, we have used cryo-electron microscopy (cryo-EM) and three-dimensional image reconstruction (cryo-reconstruction) and X-ray crystallography to determine the structure of the AAV9 capsid at 9.7- and 2.8-Å resolutions, respectively. The AAV9 capsid exhibits the surface topology conserved in all AAVs: depressions at each icosahedral two-fold symmetry axis and surrounding each five-fold axis, three separate protrusions surrounding each three-fold axis, and a channel at each five-fold axis. The AAV9 viral protein (VP) has a conserved core structure, consisting of an eight-stranded, β-barrel motif and the αA helix, which are present in all parvovirus structures. The AAV9 VP differs in nine variable surface regions (VR-I to -IX) compared to AAV4, but at only three (VR-I, VR-II, and VR-IV) compared to AAV2 and AAV8. VR-I differences modify the raised region of the capsid surface between the two-fold and five-fold depressions. The VR-IV difference produces smaller three-fold protrusions in AAV9 that are less "pointed" than AAV2 and AAV8. Significantly, residues in the AAV9 VRs have been identified as important determinants of cellular tropism and transduction and dictate its antigenic diversity from AAV2. Hence, the AAV9 VRs likely confer the unique infection phenotypes of this serotype.
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Affiliation(s)
- Michael A. DiMattia
- Department of Biochemistry and Molecular Biology, Center for Structural Biology, McKnight Brain Institute, College of Medicine, University of Florida, Gainesville, Florida, USA
| | - Hyun-Joo Nam
- Department of Biochemistry and Molecular Biology, Center for Structural Biology, McKnight Brain Institute, College of Medicine, University of Florida, Gainesville, Florida, USA
| | - Kim Van Vliet
- Department of Biochemistry and Molecular Biology, Center for Structural Biology, McKnight Brain Institute, College of Medicine, University of Florida, Gainesville, Florida, USA
| | - Matthew Mitchell
- Department of Biochemistry and Molecular Biology, Center for Structural Biology, McKnight Brain Institute, College of Medicine, University of Florida, Gainesville, Florida, USA
| | - Antonette Bennett
- Department of Biochemistry and Molecular Biology, Center for Structural Biology, McKnight Brain Institute, College of Medicine, University of Florida, Gainesville, Florida, USA
| | - Brittney L. Gurda
- Department of Biochemistry and Molecular Biology, Center for Structural Biology, McKnight Brain Institute, College of Medicine, University of Florida, Gainesville, Florida, USA
| | - Robert McKenna
- Department of Biochemistry and Molecular Biology, Center for Structural Biology, McKnight Brain Institute, College of Medicine, University of Florida, Gainesville, Florida, USA
| | - Norman H. Olson
- Department of Chemistry and Biochemistry and Division of Biological Sciences, University of California—San Diego, La Jolla, California, USA
| | - Robert S. Sinkovits
- Department of Chemistry and Biochemistry and Division of Biological Sciences, University of California—San Diego, La Jolla, California, USA
| | - Mark Potter
- Department of Pediatrics and Powell Gene Therapy Center, Division of Cell and Molecular Therapy, College of Medicine, University of Florida, Gainesville, Florida, USA
| | - Barry J. Byrne
- Department of Pediatrics and Powell Gene Therapy Center, Division of Cell and Molecular Therapy, College of Medicine, University of Florida, Gainesville, Florida, USA
| | - George Aslanidi
- Department of Pediatrics and Powell Gene Therapy Center, Division of Cell and Molecular Therapy, College of Medicine, University of Florida, Gainesville, Florida, USA
| | - Sergei Zolotukhin
- Department of Pediatrics and Powell Gene Therapy Center, Division of Cell and Molecular Therapy, College of Medicine, University of Florida, Gainesville, Florida, USA
| | - Nicholas Muzyczka
- Department of Molecular Genetics and Microbiology and Powell Gene Therapy Center, College of Medicine, University of Florida, Gainesville, Florida, USA
| | - Timothy S. Baker
- Department of Chemistry and Biochemistry and Division of Biological Sciences, University of California—San Diego, La Jolla, California, USA
| | - Mavis Agbandje-McKenna
- Department of Biochemistry and Molecular Biology, Center for Structural Biology, McKnight Brain Institute, College of Medicine, University of Florida, Gainesville, Florida, USA
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19
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Allaume X, El-Andaloussi N, Leuchs B, Bonifati S, Kulkarni A, Marttila T, Kaufmann JK, Nettelbeck DM, Kleinschmidt J, Rommelaere J, Marchini A. Retargeting of rat parvovirus H-1PV to cancer cells through genetic engineering of the viral capsid. J Virol 2012; 86:3452-65. [PMID: 22258256 PMCID: PMC3302485 DOI: 10.1128/jvi.06208-11] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/02/2011] [Accepted: 01/03/2012] [Indexed: 11/20/2022] Open
Abstract
The rat parvovirus H-1PV is a promising anticancer agent given its oncosuppressive properties and the absence of known side effects in humans. H-1PV replicates preferentially in transformed cells, but the virus can enter both normal and cancer cells. Uptake by normal cells sequesters a significant portion of the administered viral dose away from the tumor target. Hence, targeting H-1PV entry specifically to tumor cells is important to increase the efficacy of parvovirus-based treatments. In this study, we first found that sialic acid plays a key role in H-1PV entry. We then genetically engineered the H-1PV capsid to improve its affinity for human tumor cells. By analogy with the resolved crystal structure of the closely related parvovirus minute virus of mice, we developed an in silico three-dimensional (3D) model of the H-1PV wild-type capsid. Based on this model, we identified putative amino acids involved in cell membrane recognition and virus entry at the level of the 2-fold axis of symmetry of the capsid, within the so-called dimple region. In situ mutagenesis of these residues significantly reduced the binding and entry of H-1PV into permissive cells. We then engineered an entry-deficient viral capsid and inserted a cyclic RGD-4C peptide at the level of its 3-fold axis spike. This peptide binds α(v)β(3) and α(v)β(5) integrins, which are overexpressed in cancer cells and growing blood vessels. The insertion of the peptide rescued viral infectivity toward cells overexpressing α(v)β(5) integrins, resulting in the efficient killing of these cells by the reengineered virus. This work demonstrates that H-1PV can be genetically retargeted through the modification of its capsid, showing great promise for a more efficient use of this virus in cancer therapy.
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Affiliation(s)
- Xavier Allaume
- Tumour Virology Division F010a and Inserm Unit 701,b German Cancer Research Center (DKFZ), Im Neuenheimer Feld 242, Heidelberg, Germany.
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20
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Eggers PK, Becker T, Melvin MK, Boulos RA, James E, Morellini N, Harvey AR, Dunlop SA, Fitzgerald M, Stubbs KA, Raston CL. Composite fluorescent vesicles based on ionic and cationic amphiphilic calix[4]arenes. RSC Adv 2012. [DOI: 10.1039/c2ra20491f] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
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21
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Streck AF, Bonatto SL, Homeier T, Souza CK, Gonçalves KR, Gava D, Canal CW, Truyen U. High rate of viral evolution in the capsid protein of porcine parvovirus. J Gen Virol 2011; 92:2628-2636. [DOI: 10.1099/vir.0.033662-0] [Citation(s) in RCA: 47] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
In recent years, it has been shown that some parvoviruses exhibit high substitution rates, close to those of RNA viruses. In order to monitor and determine new mutations in porcine parvovirus (PPV), recent PPV field isolates from Austria, Brazil, Germany and Switzerland were sequenced and analysed. These samples, together with sequences retrieved from GenBank, were included in three datasets, consisting of the complete NS1 and VP1 genes and a partial VP1 gene. For each dataset, the nucleotide substitution rate and the molecular clock were determined. Analysis of the PPV field isolates revealed that a recently described amino acid substitution, S436T, appeared to be common in the VP2 protein in the Austrian, Brazilian and German virus populations. Furthermore, new amino acid substitutions were identified, located mainly in the viral capsid loops. By inferring the evolutionary dynamics of the PPV sequences, nucleotide substitution rates of approximately 10−5 substitutions per site per year for the non-structural protein gene and 10−4 substitutions per site per year for the capsid protein gene (for both viral protein datasets) were found. The latter rate is similar to those commonly found in RNA viruses. An association of the phylogenetic tree with the molecular clock analysis revealed that the mutations on which the divergence for both capsid proteins was based occurred in the past 30 years. Based on these findings, it was concluded that PPV variants are continuously evolving and that vaccines, which are based mainly on strains isolated about 30 years ago, should perhaps be updated.
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Affiliation(s)
- André Felipe Streck
- Institute for Animal Hygiene and Veterinary Public Health, Faculty of Veterinary Medicine, University of Leipzig, An den Tierkliniken 1, 04103 Leipzig, Germany
| | - Sandro Luis Bonatto
- Laboratório de Biologia Genômica e Molecular, Pontifícia Universidade Católica, Av. Ipiranga 6681, Prédio12, bloco C, sala 172, 90619-900 Porto Alegre, Brazil
| | - Timo Homeier
- Institute for Animal Hygiene and Veterinary Public Health, Faculty of Veterinary Medicine, University of Leipzig, An den Tierkliniken 1, 04103 Leipzig, Germany
| | - Carine Kunzler Souza
- Laboratório de Virologia, Faculdade de Veterinária, Universidade Federal do Rio Grande do Sul, Av. Bento Gonçalves 9090, Prédio 42.602, CEP 91540-000, Porto Alegre, Brazil
| | - Karla Rathje Gonçalves
- Laboratório de Virologia, Faculdade de Veterinária, Universidade Federal do Rio Grande do Sul, Av. Bento Gonçalves 9090, Prédio 42.602, CEP 91540-000, Porto Alegre, Brazil
| | - Danielle Gava
- Laboratório de Virologia, Faculdade de Veterinária, Universidade Federal do Rio Grande do Sul, Av. Bento Gonçalves 9090, Prédio 42.602, CEP 91540-000, Porto Alegre, Brazil
| | - Cláudio Wageck Canal
- Laboratório de Virologia, Faculdade de Veterinária, Universidade Federal do Rio Grande do Sul, Av. Bento Gonçalves 9090, Prédio 42.602, CEP 91540-000, Porto Alegre, Brazil
| | - Uwe Truyen
- Institute for Animal Hygiene and Veterinary Public Health, Faculty of Veterinary Medicine, University of Leipzig, An den Tierkliniken 1, 04103 Leipzig, Germany
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22
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Abstract
Adeno-associated viruses (AAV) are widely spread throughout the human population, yet no pathology has been associated with infection. This fact, together with the availability of simple molecular techniques to alter the packaged viral genome, has made AAV a serious contender in the search for an ideal gene therapy delivery vehicle. However, our understanding of the intriguing features of this virus is far from exhausted and it is likely that the mechanisms underlying the viral lifestyle will reveal possible novel strategies that can be employed in future clinical approaches. One such aspect is the unique approach AAV has evolved in order to establish latency. In the absence of a cellular milieu that will support productive viral replication, wild-type AAV can integrate its genome site specifically into a locus on human chromosome 19 (termed AAVS1), where it resides without apparent effects on the host cell until cellular conditions are changed by outside influences, such as adenovirus super-infection, which will lead to the rescue of the viral genome and productive replication. This article will introduce the biology of AAV, the unique viral strategy of targeted genome integration and address relevant questions within the context of attempts to establish therapeutic approaches that will utilize targeted gene addition to the human genome.
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Affiliation(s)
- Els Henckaerts
- Department of Infectious Diseases, King's College London School of Medicine, Guy's Hospital, London, SE1 9RT, UK
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