1
|
Canuti M, Pénzes JJ, Lang AS. A new perspective on the evolution and diversity of the genus Amdoparvovirus (family Parvoviridae) through genetic characterization, structural homology modeling, and phylogenetics. Virus Evol 2022; 8:veac056. [PMID: 35783582 PMCID: PMC9242002 DOI: 10.1093/ve/veac056] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/12/2022] [Revised: 05/13/2022] [Accepted: 06/13/2022] [Indexed: 12/11/2022] Open
Abstract
Amdoparvoviruses (genus Amdoparvovirus, family Parvoviridae) are primarily viruses of carnivorans, but recent studies have indicated that their host range might also extend to rodents and chiropterans. While their classification is based on the full sequence of the major nonstructural protein (NS1), several studies investigating amdoparvoviral diversity have been focused on partial sequences, leading to difficulties in accurately determining species demarcations and leaving several viruses unclassified. In this study, while reporting the complete genomic sequence of a novel amdoparvovirus identified in an American mink (British Columbia amdoparvovirus, BCAV), we studied the phylogenetic relationships of all amdoparvovirus-related sequences and provide a comprehensive reevaluation of their diversity and evolution. After excluding recombinant sequences, phylogenetic and pairwise sequence identity analyses allowed us to define fourteen different viruses, including the five currently classified species, BCAV, and four additional viruses that fulfill the International Committee on Taxonomy of Viruses criteria to be classified as species. We show that the group of viruses historically known as Aleutian mink disease virus (species Carnivore amdoparvovirus 1) should be considered as a cluster of at least four separate viral species that have been co-circulating in mink farms, facilitating the occurrence of inter-species recombination. Genome organization, splicing donor and acceptor sites, and protein sequence motifs were surprisingly conserved within the genus. The sequence of the major capsid protein virus protein 2 (VP2) was significantly more conserved between and within species compared to NS1, a phenomenon possibly linked to antibody-dependent enhancement (ADE). Homology models suggest a remarkably high degree of conservation of the spikes located near the icosahedral threefold axis of the capsid, comprising the surface region associated with ADE. A surprisingly high number of divergent amino acid positions were found in the luminal threefold and twofold axes of the capsid, regions of hitherto unknown function. We emphasize the importance of complete genome analyses and, given the marked phylogenetic inconsistencies across the genome, advise to obtain the complete coding sequences of divergent strains. Further studies on amdoparvovirus biology and structure as well as epidemiological and virus discovery investigations are required to better characterize the ecology and evolution of this important group of viruses.
Collapse
Affiliation(s)
- Marta Canuti
- Department of Biology, Memorial University of Newfoundland, 45 Arctic Ave., St. John’s NL A1C 5S7, Canada
| | - Judit J Pénzes
- Institute for Quantitative Biomedicine, Rutgers the State University of New Jersey, 174 Frelinghuysen Rd, Piscataway, NJ 08854, USA
| | - Andrew S Lang
- Department of Biology, Memorial University of Newfoundland, 45 Arctic Ave., St. John’s NL A1C 5S7, Canada
| |
Collapse
|
2
|
Seroprevalence and Molecular Epidemiology of Aleutian Disease in Various Countries during 1972-2021: A Review and Meta-Analysis. Animals (Basel) 2021; 11:ani11102975. [PMID: 34679996 PMCID: PMC8533000 DOI: 10.3390/ani11102975] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/13/2021] [Revised: 10/08/2021] [Accepted: 10/13/2021] [Indexed: 12/31/2022] Open
Abstract
Simple Summary Aleutian disease is caused by the Aleutian mink disease virus and is one of the most serious infectious diseases that affect the family Mustelidae, including the American mink, wild European mink, weasels, badgers and other animal species, such as skunks, raccoons, dogs, cats and mice, as well as humans. Effective treatments and vaccines against Aleutian disease have not been developed to date. Prophylactic programs that focus on the identification and elimination of infected mink are one of the methods of controlling the negative outcomes of Aleutian disease. This article analyses the seroprevalence of Aleutian mink disease virus infections in American and European mink and other species around the world, and reviews recent knowledge relating to the molecular epidemiology of the Aleutian mink disease virus. Abstract Aleutian disease (AD) poses a serious threat to both free-ranging and farmed mink around the world. The disease is caused by the Aleutian mink disease virus (AMDV), which also poses a health risk for other members of the family Mustelidae, including wild mink, weasels, badgers and other animal species. This article analyses the seroprevalence of AMDV infections in mink and other species around the world, and reviews recent knowledge relating to the molecular epidemiology of the AMDV. Depending on the applied diagnostic technique and the country, the prevalence of anti-AMDV antibodies or AMDV DNA was established at 21.60–100.00% in farmed American mink, 0.00–93.30% in free-ranging American mink and 0.00–25.00% in European mink. Anti-AMDV antibodies or AMDV DNA were also detected in other free-living fur-bearing animals in Europe and Canada, where their prevalence was determined at 0.00–32.00% and 0.00–70.50%, respectively. This may indicate a potential threat to various animal species. AMDV strains are not clustered into genotypes based on the geographic origin, year of isolation or pathogenicity. The isolates that were identified on mink farms around the world originated from North America because American mink were introduced to Europe and Asia for breeding purposes and to restock natural populations.
Collapse
|
3
|
Duplex PCR for Detection of Aleutian Disease Virus from Biological and Environmental Samples. ACTA VET-BEOGRAD 2019. [DOI: 10.2478/acve-2019-0034] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Abstract
Aleutian disease is one of the most serious disease entities affecting mink farms. The disease causes significant economic losses in mink breeding countries. The aim of the study was to optimize a diagnostic test based on duplex PCR to enable detection of Aleutian disease virus in biological and environmental samples.
Blood (n = 40) and spleen (n = 40) samples from animals with suspected infection, and swabs from cages in which infected animals were kept (n = 20) were used for analysis. DNA was isolated from the samples, followed by optimization of the duplex PCR reaction targeting sequences coding NS1 and VP2 proteins. The qPCR method was used to determine the sensitivity of the reaction. The specificity of the analysis was confirmed by the sequencing results.
Optimized duplex PCR enabled detection of Aleutian Mink Disease Virus (AMDV) genetic material in biological and environmental samples. Testing of the sensitivity of the method indicated clear amplification for both primer pairs at 102 copies of viral DNA in a reaction. Sequencing confirmed the specificity of the reaction, which in the case of both primer pairs indicated an over 90% agreement between the isolates and the variants of the virus from the databases.
The use of duplex PCR to detect two regions of the AMDV genome may increase the sensitivity and specificity of the method and significantly expand the possibilities of further analysis based on sequencing.
Collapse
|
4
|
Kowalczyk M, Gąsiorek B, Kostro K, Borzym E, Jakubczak A. Breeding parameters on a mink farm infected with Aleutian mink disease virus following the use of methisoprinol. Arch Virol 2019; 164:2691-2698. [PMID: 31428916 PMCID: PMC6768903 DOI: 10.1007/s00705-019-04375-x] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/08/2018] [Accepted: 05/18/2019] [Indexed: 11/26/2022]
Abstract
Aleutian mink disease virus is one of the greatest threats to modern mink farming. The disease reduces fecundity and causes high mortality among kits. The aim of this study was to evaluate the effectiveness of methisoprinol in counteracting the effects of Aleutian disease, both by inhibiting replication of the virus and by mitigating the harmful effects of the disease on the fecundity and weight of infected animals. The study included 300 individuals with confirmed infection, divided according to antibody titres into three experimental groups, which received a 20% methisoprinol solution, and three control groups, which did not receive the immunostimulant. In the mink from the experimental groups, the number of copies of the genetic material of the virus in the spleens and lymph nodes was one order of magnitude lower than in the case of the control groups. Mink receiving the supplement also showed higher fecundity (on average 5.83 in the experimental groups and 4.83 in the control groups), and the weight of their offspring before slaughter was over 200 g higher. Given the lack of effective methods for immunoprophylaxis and treatment, methisoprinol supplementation can be an effective means of counteracting the effects of AMDV on persistently infected farms.
Collapse
Affiliation(s)
- Marek Kowalczyk
- Department of Biological Basis of Animal Production, Faculty of Biology, Animal Sciences and Bioeconomy, University of Life Sciences in Lublin, Akademicka 13, 20-950, Lublin, Poland
| | - Bolesław Gąsiorek
- Department of Epizootiology and Clinic of Infectious Diseases, Faculty of Veterinary Medicine, University of Life Sciences, Głęboka 30, 20-612, Lublin, Poland
| | - Krzysztof Kostro
- Department of Epizootiology and Clinic of Infectious Diseases, Faculty of Veterinary Medicine, University of Life Sciences, Głęboka 30, 20-612, Lublin, Poland
| | - Ewa Borzym
- Department of Fish Diseases, National Veterinary Research Institute, 57 al. Partyzantów, 24-100, Pulawy, Poland
| | - Andrzej Jakubczak
- Department of Biological Basis of Animal Production, Faculty of Biology, Animal Sciences and Bioeconomy, University of Life Sciences in Lublin, Akademicka 13, 20-950, Lublin, Poland.
| |
Collapse
|
5
|
A comparative molecular characterization of AMDV strains isolated from cases of clinical and subclinical infection. Virus Genes 2018; 54:561-569. [PMID: 29845505 DOI: 10.1007/s11262-018-1576-x] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/22/2018] [Accepted: 05/23/2018] [Indexed: 10/16/2022]
Abstract
The Aleutian mink disease virus (AMDV) is one of the most serious threats to modern mink breeding. The disease can have various courses, from progressive to subclinical infections. The objective of the study was to provide a comparative molecular characterization of isolates of AMDV from farms with a clinical and subclinical course of the disease. The qPCR analysis showed a difference of two orders of magnitude between the number of copies of the viral DNA on the farm with the clinical course of the disease (105) and the farm with the subclinical course (103). The sequencing results confirm a high level of homogeneity within each farm and variation between them. The phylogenetic analysis indicates that the variants belonging to different farms are closely related and occupy different branches of the same clade. The in silico analysis of the effect of differences in the sequence encoding the VP2 protein between the farms revealed no effect of the polymorphism on its functionality. The close phylogenetic relationship between the isolates from the two farms, the synonymous nature of most of the polymorphisms and the potentially minor effect on the functionality of the protein indicate that the differences in the clinical picture may be due not only to polymorphisms in the nucleotide and amino acid sequences, but also to the stage of infection on the farm and the degree of stabilization of the pathogen-host relationship.
Collapse
|
6
|
Xi J, Zhang Y, Wang J, Yu Y, Zhang X, Li Z, Cui S, Liu W. Generation of an infectious clone of AMDV and identification of capsid residues essential for infectivity in cell culture. Virus Res 2017; 242:58-65. [DOI: 10.1016/j.virusres.2017.09.011] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/10/2017] [Revised: 08/25/2017] [Accepted: 09/04/2017] [Indexed: 10/18/2022]
|
7
|
Ma F, Zhang L, Wang Y, Lu R, Hu B, Lv S, Xue X, Li X, Ling M, Fan S, Zhang H, Yan X. Development of a Peptide ELISA for the Diagnosis of Aleutian Mink Disease. PLoS One 2016; 11:e0165793. [PMID: 27802320 PMCID: PMC5089682 DOI: 10.1371/journal.pone.0165793] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/29/2016] [Accepted: 10/18/2016] [Indexed: 01/26/2023] Open
Abstract
Aleutian disease (AD) is a common immunosuppressive disease in mink farms world-wide. Since the 1980s, counterimmunoelectrophoresis (CIEP) has been the main detection method for infection with the Aleutian Mink Disease Virus (AMDV). In this study, six peptides derived from the AMDV structural protein VP2 were designed, synthesized, and used as ELISA antigens to detect anti-AMDV antibodies in the sera of infected minks. Serum samples were collected from 764 minks in farms from five different provinces, and analyzed by both CIEP (a gold standard) and peptide ELISA. A peptide designated P1 (415 aa-433 aa) exhibited good antigenicity. A novel ELISA was developed using ovalbumin-linked peptide P1 to detect anti-AMDV antibodies in mink sera. The sensitivity and specificity of the peptide ELISA was 98.0% and 97.5%, respectively. Moreover, the ELISA also detected 342 early-stage infected samples (negative by CIEP and positive by PCR), of which 43.6% (149/342) were true positives. These results showed that the peptide ELISA had better sensitivity compared with CIEP, and therefore could be preferable over CIEP for detecting anti-AMDV antibodies in serological screening.
Collapse
Affiliation(s)
- Fanshu Ma
- Division of Infectious Diseases of Special Animal, Institute of Special Animal and Plant Sciences, The Chinese Academy of Agricultural Sciences, Changchun, China
| | - Lei Zhang
- Division of Infectious Diseases of Special Animal, Institute of Special Animal and Plant Sciences, The Chinese Academy of Agricultural Sciences, Changchun, China
| | - Yang Wang
- Division of Infectious Diseases of Special Animal, Institute of Special Animal and Plant Sciences, The Chinese Academy of Agricultural Sciences, Changchun, China
| | - Rongguang Lu
- Division of Infectious Diseases of Special Animal, Institute of Special Animal and Plant Sciences, The Chinese Academy of Agricultural Sciences, Changchun, China
| | - Bo Hu
- Division of Infectious Diseases of Special Animal, Institute of Special Animal and Plant Sciences, The Chinese Academy of Agricultural Sciences, Changchun, China
| | - Shuang Lv
- Division of Infectious Diseases of Special Animal, Institute of Special Animal and Plant Sciences, The Chinese Academy of Agricultural Sciences, Changchun, China
| | - Xianghong Xue
- Division of Infectious Diseases of Special Animal, Institute of Special Animal and Plant Sciences, The Chinese Academy of Agricultural Sciences, Changchun, China
| | - Xintong Li
- Division of Infectious Diseases of Special Animal, Institute of Special Animal and Plant Sciences, The Chinese Academy of Agricultural Sciences, Changchun, China
| | - Mingyu Ling
- Division of Infectious Diseases of Special Animal, Institute of Special Animal and Plant Sciences, The Chinese Academy of Agricultural Sciences, Changchun, China
| | - Sining Fan
- Division of Infectious Diseases of Special Animal, Institute of Special Animal and Plant Sciences, The Chinese Academy of Agricultural Sciences, Changchun, China
| | - Hailing Zhang
- Division of Infectious Diseases of Special Animal, Institute of Special Animal and Plant Sciences, The Chinese Academy of Agricultural Sciences, Changchun, China
| | - Xijun Yan
- Division of Infectious Diseases of Special Animal, Institute of Special Animal and Plant Sciences, The Chinese Academy of Agricultural Sciences, Changchun, China
| |
Collapse
|
8
|
Identification of a novel Aleutian mink disease virus B-cell epitope using a monoclonal antibody against VP2 protein. Virus Res 2016; 223:39-42. [PMID: 27354304 DOI: 10.1016/j.virusres.2016.06.014] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/25/2016] [Revised: 06/17/2016] [Accepted: 06/22/2016] [Indexed: 11/22/2022]
Abstract
Aleutian mink disease virus (AMDV) is a parvovirus that causes an immune complex-mediated disease in minks. Capsid protein VP2 is a major structural viral protein and can be used to diagnose AMDV. In this study, a specific monoclonal antibody, 1M13, was produced against the AMDV VP2 protein (amino acids 291-502). A linear VP2-protein epitope was identified by subjecting a series of partially overlapping synthesized peptides to be enzyme-linked immunosorbent assay (ELISA) analysis. The results indicated that (386)HLQQNFSTRYIYD(398) was the minimal linear epitope that could be recognized by mAb 1M13. ELISA assays revealed that mink anti-AMDV sera could also recognize the minimal linear epitope. Sequence alignments demonstrated that the linear epitope is highly conserved among AMDV strains except (386)H and is less conserved among Raccoon dog amdovirus, Gray fox amdovirus, Red fox amdovirus, Bat parvovirus and Mink enteritis parvovirus. Taken together, the generation of this VP2-specific mAb with a defined linear peptide epitope may have potential applications in the development of suitable diagnostic techniques for AMDV.
Collapse
|
9
|
Xi J, Wang J, Yu Y, Zhang X, Mao Y, Hou Q, Liu W. Genetic characterization of the complete genome of an Aleutian mink disease virus isolated in north China. Virus Genes 2016; 52:463-73. [PMID: 27007772 DOI: 10.1007/s11262-016-1320-3] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/06/2016] [Accepted: 03/12/2016] [Indexed: 12/16/2022]
Abstract
The genome of a highly pathogenic strain of Aleutian disease mink virus (AMDV-BJ) isolated from a domestic farm in North China has been determined and compared with other strains. Alignment analysis of the major structural protein VP2 revealed that AMDV-BJ is unique among 17 other AMDV strains. Compared with the nonpathogenic strain ADV-G, the 3' end Y-shaped hairpin was highly conserved, while a 4-base deletion in the 5' U-shaped terminal palindrome resulted in a different unpaired "bubble" group near the NS1-binding region of the 5' end hairpin which may affect replication efficiency in vivo. We also performed a protein analysis of the NS1, NS2, and new-confirmed NS3 of AMDV-BJ with some related AMDV DNA sequence published, providing information on evolution of AMDV genes. This study shows a useful method to obtain the full-length genome of AMDV and some other parvoviruses.
Collapse
Affiliation(s)
- Ji Xi
- State Key Laboratory of Agrobiotechnology, Department of Biochemistry and Molecular Biology, College of Biological Sciences, China Agricultural University, No. 2 Yuanmingyuan West Road, Haidian District, Beijing, 100193, China
| | - Jigui Wang
- State Key Laboratory of Agrobiotechnology, Department of Biochemistry and Molecular Biology, College of Biological Sciences, China Agricultural University, No. 2 Yuanmingyuan West Road, Haidian District, Beijing, 100193, China
| | - Yongle Yu
- State Key Laboratory of Agrobiotechnology, Department of Biochemistry and Molecular Biology, College of Biological Sciences, China Agricultural University, No. 2 Yuanmingyuan West Road, Haidian District, Beijing, 100193, China
| | - Xiaomei Zhang
- State Key Laboratory of Agrobiotechnology, Department of Biochemistry and Molecular Biology, College of Biological Sciences, China Agricultural University, No. 2 Yuanmingyuan West Road, Haidian District, Beijing, 100193, China
| | - Yaping Mao
- State Key Laboratory of Agrobiotechnology, Department of Biochemistry and Molecular Biology, College of Biological Sciences, China Agricultural University, No. 2 Yuanmingyuan West Road, Haidian District, Beijing, 100193, China
| | - Qiang Hou
- State Key Laboratory of Agrobiotechnology, Department of Biochemistry and Molecular Biology, College of Biological Sciences, China Agricultural University, No. 2 Yuanmingyuan West Road, Haidian District, Beijing, 100193, China
| | - Weiquan Liu
- State Key Laboratory of Agrobiotechnology, Department of Biochemistry and Molecular Biology, College of Biological Sciences, China Agricultural University, No. 2 Yuanmingyuan West Road, Haidian District, Beijing, 100193, China.
| |
Collapse
|
10
|
Nelson CD, Palermo LS, Hafenstein SL, Parrish CR. Different mechanisms of antibody-mediated neutralization of parvoviruses revealed using the Fab fragments of monoclonal antibodies. Virology 2007; 361:283-93. [PMID: 17217977 PMCID: PMC1991280 DOI: 10.1016/j.virol.2006.11.032] [Citation(s) in RCA: 42] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/24/2006] [Revised: 10/25/2006] [Accepted: 11/29/2006] [Indexed: 11/20/2022]
Abstract
Antibody binding and neutralization are major host defenses against viruses, yet the mechanisms are often not well understood. Eight monoclonal antibodies and their Fab fragments were tested for neutralization of canine parvovirus and feline panleukopenia virus. All IgGs neutralized >85% of virus infectivity. Two Fabs neutralized when present at 5 nM, while the others gave little or no neutralization even at 20-100 nM. The antibodies bind two antigenic sites on the capsids which overlap the binding site of the host transferrin receptor (TfR). There was no specific correlation between Fab binding affinity and neutralization. All Fabs reduced capsid binding of virus to purified feline TfR in vitro, but the highly neutralizing Fabs were more efficient competitors. All partially prevented binding and uptake of capsids by feline TfR on cells. The virus appears adapted to allow some infectivity in the presence of at least low levels of antibodies.
Collapse
Affiliation(s)
- Christian D.S. Nelson
- Baker Institute for Animal Health, and Department of Microbiology and Immunology, Collegeof Veterinary Medicine, Cornell University, Ithaca, NY 14853 USA
| | - Laura S. Palermo
- Baker Institute for Animal Health, and Department of Microbiology and Immunology, Collegeof Veterinary Medicine, Cornell University, Ithaca, NY 14853 USA
| | - Susan L. Hafenstein
- Department of Biological Sciences, Lilley Hall, Purdue University, West Lafayette, IN 47907-1392 USA
| | - Colin R. Parrish
- Baker Institute for Animal Health, and Department of Microbiology and Immunology, Collegeof Veterinary Medicine, Cornell University, Ithaca, NY 14853 USA
- *Corresponding author: Colin R. Parrish, Baker Institute for Animal Health, and Department of Microbiology and Immunology, College of Veterinary Medicine, Cornell University, Ithaca, NY 14853 USA Telephone: (607) 256-5649 Fax: (607) 256-5608
| |
Collapse
|
11
|
Zhang HG, Xie J, Dmitriev I, Kashentseva E, Curiel DT, Hsu HC, Mountz JD. Addition of six-His-tagged peptide to the C terminus of adeno-associated virus VP3 does not affect viral tropism or production. J Virol 2002; 76:12023-31. [PMID: 12414944 PMCID: PMC136915 DOI: 10.1128/jvi.76.23.12023-12031.2002] [Citation(s) in RCA: 31] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Production of large quantities of recombinant adeno-associated virus (AAV) is difficult and not cost-effective. To overcome this problem, we have explored the feasibility of creating a recombinant AAV encoding a 6xHis tag on the VP3 capsid protein. We generated a plasmid vector containing a six-His (6xHis)-tagged AAV VP3. A second plasmid vector was generated that contained the full-length AAV capsid capable of producing VP1 and VP2, but not VP3 due to a mutation at position 2809 that encodes the start codon for VP3. These plasmids, necessary for production of AAV, were transfected into 293 cells to generate a 6xHis-tagged VP3mutant recombinant AAV. The 6xHis-tagged VP3 did not affect the formation of AAV virus, and the physical properties of the 6xHis-modified AAV were equivalent to those of wild-type particles. The 6xHis-tagged AAV did not affect the production titer of recombinant AAV and could be used to purify the recombinant AAV using an Ni-nitrilotriacetic acid column. Addition of the 6xHis tag did not alter the viral tropism compared to wild-type AAV. These observations demonstrate the feasibility of producing high-titer AAV containing a 6xHis-tagged AAV VP3 capsid protein and to utilize the 6xHis-tagged VP3 capsid to achieve high-affinity purification of this recombinant AAV.
Collapse
Affiliation(s)
- Huang-Ge Zhang
- Division of Clinical Immunology and Rheumatology, Department of Medicine, The University of Alabama at Birmingham, Birmingham, Alabama 35294, USA
| | | | | | | | | | | | | |
Collapse
|
12
|
Christensen J, Tattersall P. Parvovirus initiator protein NS1 and RPA coordinate replication fork progression in a reconstituted DNA replication system. J Virol 2002; 76:6518-31. [PMID: 12050365 PMCID: PMC136255 DOI: 10.1128/jvi.76.13.6518-6531.2002] [Citation(s) in RCA: 84] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
We show here that the DNA helicase activity of the parvoviral initiator protein NS1 is highly directional, binding to the single strand at a recessed 5' end and displacing the other strand while progressing in a 3'-to-5' direction on the bound strand. NS1 and a cellular site-specific DNA binding factor, PIF, also known as glucocorticoid modulating element binding protein, bind to the left-end minimal replication origin of minute virus of mice, forming a ternary complex. In this complex, NS1 is activated to nick one DNA strand, becoming covalently attached to the 5' end of the nick in the process and providing a 3' OH for priming DNA synthesis. In this situation, the helicase activity of NS1 did not displace the nicked strand, but the origin duplex was distorted by the NS1-PIF complex, as assayed by its sensitivity to KMnO(4) oxidation, and a stretch of about 14 nucleotides on both strands of the nicked origin underwent limited unwinding. Addition of Escherichia coli single-stranded DNA binding protein (SSB) did not lead to further unwinding. However, addition of recombinant human single-stranded DNA binding protein (RPA) to the initiation reaction catalyzed extensive unwinding of the nicked origin, suggesting that RPA may be required to form a functional replication fork. Accordingly, the unwinding mediated by NS1 and RPA promoted processive leading-strand synthesis catalyzed by recombinant human DNA polymerase delta, PCNA, and RFC, using the minimal left-end origin cloned in a plasmid as a template. The requirement for RPA, rather than SSB, in the unwinding reaction indicated that specific NS1-RPA protein interactions were formed. NS1 was tested by enzyme-linked immunosorbent assay for binding to two- or three-subunit RPA complexes expressed from recombinant baculoviruses. NS1 efficiently bound each of the baculovirus-expressed complexes, indicating that the small subunit of RPA is not involved in specific NS1 binding. No NS1 interactions were observed with E. coli SSB or other proteins included as controls.
Collapse
Affiliation(s)
- Jesper Christensen
- Institute of Medical Microbiology and Immunology, Panum Institute, University of Copenhagen, Building 24.2, Blegdamsvej 3b, Copenhagen 2200 N, Denmark.
| | | |
Collapse
|
13
|
Bloom ME, Best SM, Hayes SF, Wells RD, Wolfinbarger JB, McKenna R, Agbandje-McKenna M. Identification of aleutian mink disease parvovirus capsid sequences mediating antibody-dependent enhancement of infection, virus neutralization, and immune complex formation. J Virol 2001; 75:11116-27. [PMID: 11602751 PMCID: PMC114691 DOI: 10.1128/jvi.75.22.11116-11127.2001] [Citation(s) in RCA: 37] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/28/2001] [Accepted: 07/30/2001] [Indexed: 11/20/2022] Open
Abstract
Aleutian mink disease parvovirus (ADV) causes a persistent infection associated with circulating immune complexes, immune complex disease, hypergammaglobulinemia, and high levels of antiviral antibody. Although antibody can neutralize ADV infectivity in Crandell feline kidney cells in vitro, virus is not cleared in vivo, and capsid-based vaccines have proven uniformly ineffective. Antiviral antibody also enables ADV to infect macrophages, the target cells for persistent infection, by Fc-receptor-mediated antibody-dependent enhancement (ADE). The antibodies involved in these unique aspects of ADV pathogenesis may have specific targets on the ADV capsid. Prominent differences exist between the structure of ADV and other, more-typical parvoviruses, which can be accounted for by short peptide sequences in the flexible loop regions of the capsid proteins. In order to determine whether these short sequences are targets for antibodies involved in ADV pathogenesis, we studied heterologous antibodies against several peptides present in the major capsid protein, VP2. Of these antibodies, a polyclonal rabbit antibody to peptide VP2:428-446 was the most interesting. The anti-VP2:428-446 antibody aggregated virus particles into immune complexes, mediated ADE, and neutralized virus infectivity in vitro. Thus, antibody against this short peptide can be implicated in key facets of ADV pathogenesis. Structural modeling suggested that surface-exposed residues of VP2:428-446 are readily accessible for antibody binding. The observation that antibodies against a single target peptide in the ADV capsid can mediate both neutralization and ADE may explain the failure of capsid-based vaccines.
Collapse
Affiliation(s)
- M E Bloom
- Laboratory of Persistent Viral Diseases, Rocky Mountain Laboratories, National Institute of Allergy and Infectious Diseases, Hamilton, Montana 59840, USA.
| | | | | | | | | | | | | |
Collapse
|