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1.
PLoS Pathog ; 17(11): e1010053, 2021 11.
Artigo em Inglês | MEDLINE | ID: mdl-34748603

RESUMO

COVID-19 patients transmitted SARS-CoV-2 to minks in the Netherlands in April 2020. Subsequently, the mink-associated virus (miSARS-CoV-2) spilled back over into humans. Genetic sequences of the miSARS-CoV-2 identified a new genetic variant known as "Cluster 5" that contained mutations in the spike protein. However, the functional properties of these "Cluster 5" mutations have not been well established. In this study, we found that the Y453F mutation located in the RBD domain of miSARS-CoV-2 is an adaptive mutation that enhances binding to mink ACE2 and other orthologs of Mustela species without compromising, and even enhancing, its ability to utilize human ACE2 as a receptor for entry. Structural analysis suggested that despite the similarity in the overall binding mode of SARS-CoV-2 RBD to human and mink ACE2, Y34 of mink ACE2 was better suited to interact with a Phe rather than a Tyr at position 453 of the viral RBD due to less steric clash and tighter hydrophobic-driven interaction. Additionally, the Y453F spike exhibited resistance to convalescent serum, posing a risk for vaccine development. Thus, our study suggests that since the initial transmission from humans, SARS-CoV-2 evolved to adapt to the mink host, leading to widespread circulation among minks while still retaining its ability to efficiently utilize human ACE2 for entry, thus allowing for transmission of the miSARS-CoV-2 back into humans. These findings underscore the importance of active surveillance of SARS-CoV-2 evolution in Mustela species and other susceptible hosts in order to prevent future outbreaks.


Assuntos
Enzima de Conversão de Angiotensina 2/metabolismo , COVID-19/epidemiologia , Adaptação ao Hospedeiro , Vison/imunologia , Mutação , SARS-CoV-2/isolamento & purificação , Glicoproteína da Espícula de Coronavírus/genética , Adulto , Idoso , Enzima de Conversão de Angiotensina 2/genética , Animais , Sítios de Ligação , COVID-19/imunologia , COVID-19/terapia , COVID-19/transmissão , COVID-19/virologia , Feminino , Humanos , Imunização Passiva/estatística & dados numéricos , Masculino , Pessoa de Meia-Idade , Vison/virologia , Simulação de Dinâmica Molecular , Países Baixos/epidemiologia , Ligação Proteica , SARS-CoV-2/genética , Glicoproteína da Espícula de Coronavírus/metabolismo , Internalização do Vírus , Adulto Jovem
2.
Viruses ; 13(8)2021 08 19.
Artigo em Inglês | MEDLINE | ID: mdl-34452513

RESUMO

The recent emergence of SARS-CoV-2 in humans from a yet unidentified animal reservoir and the capacity of the virus to naturally infect pets, farmed animals and potentially wild animals has highlighted the need for serological surveillance tools. In this study, the luciferase immunoprecipitation systems (LIPS), employing the spike (S) and nucleocapsid proteins (N) of SARS-CoV-2, was used to examine the suitability of the assay for antibody detection in different animal species. Sera from SARS-CoV-2 naturally-infected mink (n = 77), SARS-CoV-2 experimentally-infected ferrets, fruit bats and hamsters and a rabbit vaccinated with a purified spike protein were examined for antibodies using the SARS-CoV-2 N and/or S proteins. From comparison with the known neutralization status of the serum samples, statistical analyses including calculation of the Spearman rank-order-correlation coefficient and Cohen's kappa agreement were used to interpret the antibody results and diagnostic performance. The LIPS immunoassay robustly detected the presence of viral antibodies in naturally infected SARS-CoV-2 mink, experimentally infected ferrets, fruit bats and hamsters as well as in an immunized rabbit. For the SARS-CoV-2-LIPS-S assay, there was a good level of discrimination between the positive and negative samples for each of the five species tested with 100% agreement with the virus neutralization results. In contrast, the SARS-CoV-2-LIPS-N assay did not consistently differentiate between SARS-CoV-2 positive and negative sera. This study demonstrates the suitability of the SARS-CoV-2-LIPS-S assay for the sero-surveillance of SARS-CoV-2 infection in a range of animal species.


Assuntos
Anticorpos Antivirais/sangue , COVID-19/veterinária , Vison/imunologia , SARS-CoV-2/imunologia , Animais , COVID-19/diagnóstico , COVID-19/epidemiologia , COVID-19/imunologia , Teste Sorológico para COVID-19 , Quirópteros/imunologia , Proteínas do Nucleocapsídeo de Coronavírus/imunologia , Monitoramento Epidemiológico , Furões/imunologia , Imunoprecipitação , Mesocricetus/imunologia , Fosfoproteínas/imunologia , Coelhos/imunologia , Estudos Soroepidemiológicos , Glicoproteína da Espícula de Coronavírus/imunologia
3.
Cell Rep ; 35(3): 109017, 2021 04 20.
Artigo em Inglês | MEDLINE | ID: mdl-33857422

RESUMO

Transmission of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) from humans to farmed mink has been observed in Europe and the US. In the infected animals, viral variants arose that harbored mutations in the spike (S) protein, the target of neutralizing antibodies, and these variants were transmitted back to humans. This raised concerns that mink might become a constant source of human infection with SARS-CoV-2 variants associated with an increased threat to human health and resulted in mass culling of mink. Here, we report that mutations frequently found in the S proteins of SARS-CoV-2 from mink are mostly compatible with efficient entry into human cells and its inhibition by soluble angiotensin-converting enzyme 2 (ACE2). In contrast, mutation Y453F reduces neutralization by an antibody with emergency use authorization for coronavirus disease 2019 (COVID-19) therapy and sera/plasma from COVID-19 patients. These results suggest that antibody responses induced upon infection or certain antibodies used for treatment might offer insufficient protection against SARS-CoV-2 variants from mink.


Assuntos
Anticorpos Neutralizantes/imunologia , Anticorpos Antivirais/imunologia , COVID-19 , Vison , SARS-CoV-2 , Glicoproteína da Espícula de Coronavírus , Células A549 , Enzima de Conversão de Angiotensina 2/imunologia , Animais , COVID-19/genética , COVID-19/imunologia , Chlorocebus aethiops , Cricetinae , Humanos , Vison/imunologia , Vison/virologia , SARS-CoV-2/genética , SARS-CoV-2/imunologia , Glicoproteína da Espícula de Coronavírus/genética , Glicoproteína da Espícula de Coronavírus/imunologia , Células Vero
4.
Emerg Microbes Infect ; 10(1): 472-480, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-33657971

RESUMO

Pandemic influenza, typically caused by the reassortment of human and avian influenza viruses, can result in severe or fatal infections in humans. Timely identification of potential pandemic viruses must be a priority in influenza virus surveillance. However, the range of host species responsible for the generation of novel pandemic influenza viruses remains unclear. In this study, we conducted serological surveys for avian and human influenza virus infections in farmed mink and determined the susceptibility of mink to prevailing avian and human virus subtypes. The results showed that farmed mink were commonly infected with human (H3N2 and H1N1/pdm) and avian (H7N9, H5N6, and H9N2) influenza A viruses. Correlational analysis indicated that transmission of human influenza viruses occurred from humans to mink, and that feed source was a probable route of avian influenza virus transmission to farmed mink. Animal experiments showed that mink were susceptible and permissive to circulating avian and human influenza viruses, and that human influenza viruses (H3N2 and H1N1/pdm), but not avian viruses, were capable of aerosol transmission among mink. These results indicate that farmed mink could be highly permissive "mixing vessels" for the reassortment of circulating human and avian influenza viruses. Therefore, to reduce the risk of emergence of novel pandemic viruses, feeding mink with raw poultry by-products should not be permitted, and epidemiological surveillance of influenza viruses in mink farms should be urgently implemented.


Assuntos
Vírus da Influenza A/patogenicidade , Vison/virologia , Infecções por Orthomyxoviridae/transmissão , Animais , Modelos Animais de Doenças , Humanos , Vírus da Influenza A Subtipo H1N1/imunologia , Vírus da Influenza A Subtipo H1N1/patogenicidade , Vírus da Influenza A Subtipo H3N2/imunologia , Vírus da Influenza A Subtipo H3N2/patogenicidade , Subtipo H7N9 do Vírus da Influenza A/imunologia , Subtipo H7N9 do Vírus da Influenza A/patogenicidade , Vírus da Influenza A Subtipo H9N2/imunologia , Vírus da Influenza A Subtipo H9N2/patogenicidade , Vírus da Influenza A/imunologia , Vison/imunologia , Testes de Neutralização , Infecções por Orthomyxoviridae/imunologia , Vírus Reordenados/imunologia , Vírus Reordenados/patogenicidade
5.
Arch Virol ; 166(1): 83-90, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-33068192

RESUMO

Aleutian mink disease (AMD), caused by Aleutian mink disease virus (AMDV), is a very important infectious disease of mink. Currently, elimination of antibody- or antigen-positive animals is the most successful strategy for eradicating AMD, but the claw-cutting method of blood sampling is difficult to perform and painful for the animal. In this study, we aimed to establish an antigen capture enzyme-linked immunosorbent assay (AC-ELISA) method for the efficient detection of AMDV antigens using fecal samples. A purified mouse monoclonal antibody (mAb) was used as the capture antibody, and a rabbit polyclonal antibody (pAb) was used as the detection antibody. The assay was optimized by adjusting a series of parameters. Using a cutoff value of 0.205, the limit of detection of the AC-ELISA for strain AMDV-G antigen was 2 µg/mL, and there was no cross-reaction with other mink viruses. The intra- and inter-assay standard deviations were below 0.046, and the correlation of variance (CV) values were 1.24-7.12% when testing fecal samples. Compared with conventional PCR results, the specificity and sensitivity were 91.5% and 90.6%, respectively, and the concordance rate between the two methods was 91.1%.


Assuntos
Vírus da Doença Aleutiana do Vison/imunologia , Doença Aleutiana do Vison/diagnóstico , Antígenos/imunologia , Ensaio de Imunoadsorção Enzimática/métodos , Vison/virologia , Doença Aleutiana do Vison/imunologia , Animais , Anticorpos Antivirais/imunologia , Proteínas do Capsídeo/imunologia , Camundongos , Camundongos Endogâmicos BALB C , Vison/imunologia , Coelhos
6.
Vet Microbiol ; 251: 108920, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-33197867

RESUMO

Canine distemper virus (CDV) is the causative agent of canine distemper (CD), which is one of the most important infectious diseases affecting wild and domestic carnivores. Vaccination represents an effective approach to prevent CDV infection among domestic carnivores. Canarypox-vectored recombinant CD vaccines (such as Recombitek CDV, PureVax Ferret Distemper, and Merial) with the CDV hemagglutinin (H) and fusion (F) genes can induce a potent immune response in dogs and ferrets. However, the vaccine's effectiveness varies with the species. In the current study, we developed a highly efficient recombinant canarypox virus termed as "ALVAC-CDV-M-F-H/C5-" that contained CDV virus-like particles (VLPs) by using the CRISPR/Cas9 gene editing method, which enabled concurrent expression of the matrix (M), H, and F genes. The recombinant strain provided faster seroconversion than the parent strain among minks as well as provided higher rates of antibody positivity than the parent strain among foxes and minks even before the administration of a second booster vaccination. We demonstrated, for the first time, that the CRISPR/Cas9 system can be applied for the rapid and efficient modification of the ALVAC-CDV-F-H genome and also that a high-dose new recombinant strain that produces CDV VLPs may present good outcomes in the prevention of CD among foxes and minks.


Assuntos
Anticorpos Antivirais/sangue , Sistemas CRISPR-Cas , Vírus da Varíola dos Canários/genética , Vírus da Cinomose Canina/genética , Vírus da Cinomose Canina/imunologia , Cinomose/prevenção & controle , Edição de Genes/métodos , Vacinas Virais/imunologia , Animais , Vírus da Varíola dos Canários/imunologia , Embrião de Galinha/citologia , Galinhas , Chlorocebus aethiops , Cães , Feminino , Fibroblastos/virologia , Raposas/imunologia , Glicoproteínas/genética , Glicoproteínas/imunologia , Hemaglutininas Virais/genética , Hemaglutininas Virais/imunologia , Masculino , Vison/imunologia , Vacinas Sintéticas/administração & dosagem , Vacinas Sintéticas/imunologia , Células Vero , Proteínas Virais de Fusão/genética , Proteínas Virais de Fusão/imunologia , Vacinas Virais/administração & dosagem , Vacinas Virais/genética
7.
Arch Virol ; 165(9): 2065-2071, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32613291

RESUMO

Mink enteritis virus (MEV) is a parvovirus that causes acute enteritis in mink. The capsid protein VP2 of MEV is a major immunogenicity that is important for disease prevention. In this study, this protein was expressed in Spodoptera frugiperda 9 cells using a recombinant baculovirus system and was observed to self-assemble into virus-like particles (VLPs) with a high hemagglutination (HA) titer (1:216). A single-dose injection of VLPs (HA titer, 1:256) resulted in complete protection of mink against virulent MEV challenge for at least 180 days. These data suggest that these MEV VLPs could be used as a vaccine for the prevention of viral enteritis in mink.


Assuntos
Proteínas do Capsídeo/genética , Proteínas do Capsídeo/imunologia , Enterite Viral do Vison/prevenção & controle , Vírus da Enterite do Vison/imunologia , Animais , Baculoviridae/genética , Baculoviridae/metabolismo , Proteínas do Capsídeo/administração & dosagem , Expressão Gênica , Vison/imunologia , Vison/virologia , Enterite Viral do Vison/imunologia , Enterite Viral do Vison/virologia , Vírus da Enterite do Vison/genética , Vírus da Enterite do Vison/patogenicidade , Proteínas Recombinantes/administração & dosagem , Proteínas Recombinantes/genética , Proteínas Recombinantes/imunologia , Células Sf9 , Spodoptera , Vacinas Virais/administração & dosagem , Vacinas Virais/genética , Vacinas Virais/imunologia , Virulência
8.
Microb Pathog ; 139: 103908, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31830583

RESUMO

Mink Aleutian disease (AMD) is the first of the three major diseases of fur animals. It is a common immunosuppressive disease in mink farms worldwide, which seriously endangers the development of the mink farming industry. Strengthening the understanding of the positive serum rate and spatial distribution of AMD is of great significance for the prevention and control of disease caused by the Aleutian virus. Therefore, we conducted a systematic review and meta-analysis to assess the seroprevalence of AMD in China. We extracted 45 studies related to the seroprevalence of Chinese AMD, with samples taken between 1981 and 2017. Our systematic review and meta-analysis results show that, during the selected period, the overall positive rate of AMD in China was 55.3% (95% CI 48.5-62.0). The results from subgroups analysis of the potential risk factors showed that the seroprevalence rate of AMD in China in the past 36 years rose from 48% (95% CI 37.0-60.5) in 1981-2009 to 61.4% (95% CI 43.6-79.3) in 2010-2017. The date of the spatial difference in AMD seroprevalence indicated that AMD seroprevalence was unevenly distributed in different regions: the number of mink in eastern China and northeastern China was relatively high, and the seroprevalence rates were 57.9%, (95% CI 46.2-69.7) and 61.3% (95% CI 53.1-69.5), respectively. Central China had the highest seroprevalence rate of AMD at 69.8% (95% CI 64.4-75.2). At the provincial level, the AMD seroprevalence rate in Jiangsu was as high as 96% (95% CI 94.1-97.8), and the AMD seroprevalence rate in Shaanxi was the lowest at 22.1% (95% CI 20.3-23.9). This suggested that the AMD seroprevalence rate in China was unevenly distributed. In other subgroups, the positive rate of AMD in adult mink was higher than in juvenile mink. This implied that the high prevalence of AMD in China was caused by multiple factors. The meta-regression results indicated that the detection method subgroup (P = 0.008) may be the source of heterogeneity. Our data system evaluated the prevalence of Aleutian disease in China in the last 37 years and a preliminary discussion on the risk factors of AMD. It may help prevent and control AMD in China. It is recommended to conduct further epidemiological testing and develop a comprehensive testing plan to determine the risk factors associated with Aleutian disease and improve the Aleutian disease control strategy.


Assuntos
Vírus da Doença Aleutiana do Vison/isolamento & purificação , Doença Aleutiana do Vison/sangue , Doença Aleutiana do Vison/epidemiologia , Doença Aleutiana do Vison/virologia , Vírus da Doença Aleutiana do Vison/classificação , Vírus da Doença Aleutiana do Vison/genética , Vírus da Doença Aleutiana do Vison/imunologia , Animais , Anticorpos Antivirais/sangue , China/epidemiologia , Feminino , Masculino , Vison/imunologia , Vison/virologia , Filogenia , Prevalência , Estudos Soroepidemiológicos
9.
Acta Vet Scand ; 61(1): 26, 2019 Jun 10.
Artigo em Inglês | MEDLINE | ID: mdl-31182127

RESUMO

BACKGROUND: Pre-weaning diarrhea (PWD) is a severe syndrome, with world-wide occurrence, affecting farmed mink (Neovison vison) kits during the lactation period. Kits affected by PWD often display clinical signs such as: yellow-white diarrhea, greasy skin, and dehydration. In severe cases the kits eventually die. It is common practice to treat PWD using antimicrobials; however the effect is not well documented. Due to the multifactorial etiology of PWD vaccine development is not feasible. The role played by the immune status of the mink kits with respect to their susceptibility to PWD is not well studied. To elucidate the possible association between PWD and total IgG serum concentration in young kits we analyzed blood collected from kits from 100 litters on two mink farms during the same breeding period, one farm being a case farm with high prevalence of PWD, and the other being a control farm with no cases of PWD. RESULTS: Kits affected by PWD had a significantly reduced weight gain compared to unaffected control kits. Litters born later in the breeding period came down with PWD at an earlier age than litters born at the start of the breeding period. We found that PWD affected kits had significantly lower concentrations of serum IgG compared to unaffected kits at 13-15 days of age (the last blood sampling point of the study). CONCLUSION: The results in this study suggest that PWD affected kits less efficiently absorbed IgG from maternal milk or had a lower intake of maternal milk, potentially contributing to the exacerbation of disease. A lower intake of IgG and/or less absorption from maternal milk could also pre-dispose kits for PWD. Future studies will be needed to elucidate if the circulating level of IgG is directly related to protection against disease and to investigate if administration of IgG could be helpful in alleviating and/or preventing PWD in mink kits.


Assuntos
Animais Lactentes/imunologia , Diarreia/veterinária , Imunoglobulina G/sangue , Vison/imunologia , Animais , Animais Lactentes/sangue , Diarreia/sangue , Diarreia/imunologia , Diarreia/patologia , Vison/sangue , Desmame , Ganho de Peso
10.
Acta Vet Scand ; 60(1): 36, 2018 Jun 18.
Artigo em Inglês | MEDLINE | ID: mdl-29914557

RESUMO

BACKGROUND: The significance of maternal immunoglobulin G (IgG) for the resistance against a number of infections affecting the health of young mink offspring is not known. Here, we present a validated immunoassay for quantification of mink IgG in serum and milk, using a commercially available polyclonal goat anti-ferret IgG antibody cross-reactive with mink IgG as both the catching and the detection antibody, in a sandwich format enzyme linked immunosorbent assay (ELISA). Using this ELISA, serum IgG concentrations was analyzed over time in both mothers and kits in order to establish a correlation between maternal IgG serum concentrations and those of the offspring. RESULTS: Intra-assay coefficient of variation (CV) for a serum sample ranged from 2.15 to 5.97% depending on the dilution, while the inter-assay CV ranged from 5.17 to 17.78%. In addition, the range of milk intra-assay CV was 2.71-5.92%, while the range of the inter-assay CV was 4.20-16.03%. Calibrating the ELISA with purified mink IgG (an in-house preparation purified from mink serum) the lower limit of detection was found to be 5 ng/mL for serum and 1 ng/mL for milk. Both serum and milk showed high precision and good linearity over a two-log dilution range. When comparing the serum IgG concentrations of the mink kits a clear within litter effect was seen, while the mean serum IgG concentrations of litters differed significantly between some of the litters (P = 0.0013). Mean maternal serum IgG concentrations correlated positively with the IgG serum concentration of the corresponding offspring sampled over a 3 week period (R2 = 0.63). CONCLUSIONS: A calibrated and reproducible sandwich ELISA for quantifying mink IgG concentrations in both milk and serum with high analytical sensitivity was developed and validated. The results in this study corroborate previous investigations supporting the usability of the ELISA, paving the way for investigations into the importance of maternal IgG in milk and in serum for the welfare and health of the offspring.


Assuntos
Ensaio de Imunoadsorção Enzimática/veterinária , Imunoglobulina G/metabolismo , Leite/química , Vison/imunologia , Animais , Calibragem , Ensaio de Imunoadsorção Enzimática/métodos , Feminino , Imunoglobulina G/sangue
11.
Viral Immunol ; 31(1): 69-77, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-28829241

RESUMO

Aleutian mink disease (AD) is a chronic viral infection that causes autoimmune disorders in minks and presents a significant economic burden on mink farming. Despite the substantial challenges presented by AD, no effective vaccine is available and only partial protection has been achieved. We constructed a whole-gene nucleic acid vaccine from an isolated virulent Aleutian mink disease virus (ADV) strain (pcDNA3.1-ADV). Based on this whole-gene nucleic acid vaccine, we generated truncated mutant constructs by removing portions of the ADV VP2 gene using overlap extension polymerase chain reaction. pcDNA3.1-ADV-428 lacks nucleotides encoding VP2 amino acid residues 428-466, and pcDNA3.1-ADV-428-487 harbors additional deletion of nucleotides coding for VP2 amino acid residues 487-501. We also generated nucleic acid vaccines for the ADV NS1 gene, truncated ADV NS1 gene, ADV VS2 gene, and truncated ADV VS2 gene: pcDNA3.1-NS1, pcDNA3.1-NS1-D, pcDNA3.1-VP2, and pcDNA3.1-VP2-D, respectively. The immunogenicity of the seven DNA vaccines was confirmed by immunofluorescent evaluation. Sixty female minks were divided into 10 groups: seven groups were immunized with the DNA vaccines, one control group was injected with phosphate-buffered saline, one group was immunized with pcDNA3.1 empty vector, and one group was immunized with inactivated ADV-G virus. ADV antibody levels, percentage of CD8+ cells in blood, and levels of γ-globulin and circulating immune complexes in the serum were evaluated longitudinally over 36 weeks after ADV challenge. Minks that were immunized with the pcDNA3.1-ADV-428-487 nucleic acid vaccine produced ADV antibodies. After ADV challenge, the minks immunized with pcDNA3.1-ADV-428-487 nucleic acid vaccine had lower γ-globulin content and lower CIC in serum compared to other immunization groups. Although the pcDNA3.1-ADV-428-487 nucleic acid vaccine did not demonstrate complete protection against ADV, it demonstrated marked efficacy and could potentially be used as a vaccine to prevent losses in mink populations due to ADV. Discovery of effective means to vaccinate mink against ADV will not only improve overall health of mink populations but will also reduce the economic impact of ADV.


Assuntos
Vírus da Doença Aleutiana do Vison/imunologia , Doença Aleutiana do Vison/prevenção & controle , Genoma Viral/genética , Vison/virologia , Vacinas de DNA/imunologia , Vírus da Doença Aleutiana do Vison/genética , Vírus da Doença Aleutiana do Vison/isolamento & purificação , Vírus da Doença Aleutiana do Vison/patogenicidade , Animais , Anticorpos Antivirais/sangue , Complexo Antígeno-Anticorpo/sangue , Linfócitos T CD8-Positivos/imunologia , Proteínas do Capsídeo/genética , Proteínas do Capsídeo/imunologia , Gatos , Linhagem Celular , DNA Viral/genética , Feminino , Contagem de Linfócitos , Vison/imunologia , Vacinas de DNA/administração & dosagem , Proteínas não Estruturais Virais/genética , Proteínas não Estruturais Virais/imunologia , gama-Globulinas/metabolismo
12.
Res Vet Sci ; 111: 127-134, 2017 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-28249174

RESUMO

The objective of this study was to measure the effect of selection for tolerance on the severity of the Aleutian disease (AD) lesions in mink. Sensitivity and specificity of antibody detection in the blood by counter-immunoelectrophoresis (CIEP) relative to the presence of Aleutian mink disease virus (AMDV) in the spleen by PCR in naturally infected farmed mink were also estimated. Carcasses of 680 sero-positive (CIEP-P) black mink from 28 farms in Nova Scotia, Canada, and from 132 sero-negative (CIEP-N) mink from 14 of these farms were collected at pelting time. A total of 116 of the CIEP-P mink were from three farms where animals have been selected for tolerating AD for almost 20years. The severity of the AD lesions was assessed by histopathological examination of kidneys, lungs, heart, brain and liver on a scale of 0 to 4. Sensitivity and specificity of CIEP relative to PCR were 0.97 and 0.85, respectively, and 16.5% of CIEP-N mink were PCR positive, which could be one of the reasons for the failure of virus eradication by CIEP in Canada. The CIEP-N and tolerant CIEP-P animals had 9.39 and 6.23 greater odds of showing lower lesion severity, respectively, than the CIEP-P animals (P<0.01). The CIEP-N mink had a slightly higher chance (P=0.07) of showing lower lesion severity (odds ratio 1.51) compared with tolerant CIEP-P mink. The results suggested that tolerant mink had significantly reduced severity of AD lesions despite having anti-viral antibodies and carrying the virus.


Assuntos
Vírus da Doença Aleutiana do Vison/fisiologia , Doença Aleutiana do Vison/patologia , Vison/imunologia , Doença Aleutiana do Vison/epidemiologia , Doença Aleutiana do Vison/virologia , Animais , Nova Escócia , Prevalência
13.
J Microbiol Biotechnol ; 26(12): 2214-2223, 2016 Dec 28.
Artigo em Inglês | MEDLINE | ID: mdl-27435536

RESUMO

Toll-like receptors (TLRs) can recognize conserved molecular patterns and initiate a wide range of innate and adaptive immune responses against invading infectious agents. The aim of this study was to assess the transcript profile of mink TLRs (mTLRs) in mink peripheral blood mononuclear cells (PBMCs) and a range of tissues, and to explore the potential role of mTLRs in the antiviral immune response process. The results indicated that the mTLR partial nucleotide sequences had a high degree of nucleotide identity with ferret sequences (95-98%). Phylogenetic analysis showed that mammalian TLRs grouped into five TLR families, with a closer relationship of the mTLRs with those of ferret than the other mammalian sequences. Moreover, all the mTLRs were ubiquitously expressed in lymphoid organs (spleen and lymph nodes) and PBMCs. Interestingly, the mTLR expression patterns in lung, uterus, and heart showed quite a lot of similarity. Another remarkable observation was the wide expression of mTLR1-3 mRNAs in all tissues. Among the analyzed tissues, skeletal muscle was revealed to being the lowest repertoire of mTLR expression. Additionally, mink PBMCs exposed to the canine distemper virus revealed significant upregulation of mTLR2, mTLR4, mTLR7, and mTLR8 mRNAs, indicating that mTLRs have a role in innate immunity in the mink. Collectively, our results are the first to establish the basic expression patterns of mTLRs and the relationship between mTLRs and a virus, which will contribute to better understanding of the evolution and the functions of mTLRs in the innate immune system in minks.


Assuntos
Infecções Bacterianas/veterinária , Vison/genética , Receptores Toll-Like/genética , Transcrição Genética , Viroses/veterinária , Animais , Infecções Bacterianas/genética , Infecções Bacterianas/imunologia , Infecções Bacterianas/microbiologia , Perfilação da Expressão Gênica , Imunidade Inata , Leucócitos Mononucleares/imunologia , Pulmão/imunologia , Vison/imunologia , Vison/microbiologia , Vison/virologia , Músculo Esquelético/imunologia , Baço/imunologia , Receptores Toll-Like/imunologia , Viroses/genética , Viroses/imunologia , Viroses/virologia
14.
J Virol Methods ; 235: 144-151, 2016 09.
Artigo em Inglês | MEDLINE | ID: mdl-27283885

RESUMO

There is a growing interest among mink ranchers to select their stock for tolerance to the Aleutian mink disease virus (AMDV). Enzyme-linked immunosorbent assays (ELISA) are used to identify mink which have low anti-AMDV antibody titres and are expected to tolerate the AMDV infection. The objective of this study was to calculate the accuracy of three ELISA systems which were performed on blood or serum of AMDV-inoculated American mink (Neovison vison) at five laboratories in Canada, USA, Finland, the Netherlands and Denmark. The accuracy was determined by comparing the ELISA results with antibody titres measured by the counter-immunoelectrophoresis (CIEP) using 10 two-fold serial dilutions of the plasma. Antibody titres of 880 black mink which were inoculated with a spleen homogenate from a naturally infected mink were measured between 16 and 176 weeks post-inoculation. Each ELISA result from every laboratory covered a wide range of antibody titres and the Spearman's rank correlation coefficients between CIEP and ELISA results from different laboratories varied between 0.41 and 0.83, indicating a low to moderate accuracy of ELISA systems for ranking mink by antibody titre. The recombinant VP2-based ELISA used in the Netherlands and Finland ranked the mink by antibody titres more accurately than did the AMDV-G-based ELISA platforms developed in Denmark and the USA, suggesting that the source of antigen was one of the factors affecting the accuracy of ELISA results. It was concluded that the ELISA systems, particularly those based on AMDV-G antigen, require further refinement to improve their accuracy for ranking mink by antibody titre.


Assuntos
Vírus da Doença Aleutiana do Vison/imunologia , Doença Aleutiana do Vison/imunologia , Anticorpos Antivirais/sangue , Proteínas do Capsídeo/imunologia , Ensaio de Imunoadsorção Enzimática , Animais , Canadá , Dinamarca , Imunoeletroforese , Vison/imunologia , Vison/virologia , Países Baixos , Baço
15.
PLoS One ; 10(3): e0122194, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25822750

RESUMO

Aleutian mink disease (AMD) is a chronic viral disease in farmed mink and the virus (AMDV) has been found in many free-ranging mink (Neovison vison) populations in Europe and North America. In this study, AMDV DNA and AMDV antibodies were analysed in 144 free-ranging mink hunted in Sweden. Associations between being AMDV infected (defined as positive for both viral DNA and antibodies) and the weight of the spleen, liver, kidneys, adrenal glands and body condition were calculated and the sequences of ten AMDV isolates were analysed in order to characterize the genetic relationships. In total, 46.1% of the mink were positive for AMDV antibodies and 57.6% were positive for AMDV DNA. Twenty-two percent of the mink tested on both tests (n = 133) had dissimilar results. The risk of having AMDV antibodies or being positive for AMDV DNA clearly increased with age and the majority of the mink that were two years or older were infected. Few macroscopic changes were found upon necropsy. However, the relative weight of the spleen was sexually dimorphic and was found to be slightly, but significantly (p = 0.006), heavier in AMDV infected male mink than uninfected. No association between AMDV infection and body condition, weight of the kidneys, liver or adrenal glands were found. Several different strains of AMDV were found across the country. Two of the AMDV sequences from the very north of Sweden did not group with any of the previously described groups of strains. In summary, AMDV seems to be prevalent in wild mink in Sweden and may subtly influence the weight of the spleen.


Assuntos
Vírus da Doença Aleutiana do Vison/genética , Doença Aleutiana do Vison/virologia , Vison/virologia , Doença Aleutiana do Vison/imunologia , Vírus da Doença Aleutiana do Vison/imunologia , Animais , Anticorpos Antivirais/imunologia , DNA Viral/genética , Masculino , Vison/imunologia , Filogenia , Suécia
16.
Ugeskr Laeger ; 176(40)2014 Sep 29.
Artigo em Dinamarquês | MEDLINE | ID: mdl-25294518

RESUMO

We report two cases of asthma among mink workers. The first case is about a mink farmer who had asthma that was difficult to treat. In the medical history there was no clear relation to work, and no conclusive work relation with peak flow monitoring. He had a positive histamine release test to mink urine. The second case is about a mink farm worker, who had an asthma attack when handling mink furs. Peak flow monitoring showed a clear relation to this work, but there were no signs of allergy. We conclude that these two cases suggest an increased risk of asthma among mink workers.


Assuntos
Asma Ocupacional/etiologia , Vison/imunologia , Animais , Asma Ocupacional/diagnóstico , Asma Ocupacional/tratamento farmacológico , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Pico do Fluxo Expiratório
17.
Bing Du Xue Bao ; 30(4): 450-5, 2014 Jul.
Artigo em Chinês | MEDLINE | ID: mdl-25272602

RESUMO

Aleutian mink disease parvovirus (AMDV) causes a persistent infection associated with immune complex disease, hypergammaglobulinemia, and high levels of antiviral antibodies. Despite the presence of an antibody, the virus is not cleared in vivo. Pre-existing antibodies may enhance viral infections, by Fc-receptor-mediated antibody-dependent enhancement (ADE), but the mechanism that underlies ADE has not been fully defined. Three models have been proposed, including: (1) interactions between antibody and FcR, complement C3 fragment and CR, or between C1q and C1qR, which promotes viral attachment to cells; (2) suppression of IFN-gamma-mediated host-cell antiviral gene expression by the upregulation of negative regulators of pathogen pattern recognition; and (3) the promotion of early IL-10 secretion. In addition, the role of cytokine IL-6 in ADE mediated disease development is discussed, to facilitate a better understanding of the pathogenesis of AMDV infection, as well as give insights into rational vaccine design approaches.


Assuntos
Vírus da Doença Aleutiana do Vison/imunologia , Doença Aleutiana do Vison/virologia , Anticorpos Antivirais/imunologia , Anticorpos Facilitadores , Doença Aleutiana do Vison/imunologia , Vírus da Doença Aleutiana do Vison/genética , Animais , Vison/imunologia , Vison/virologia
18.
PLoS One ; 8(12): e82978, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-24376619

RESUMO

Astroviruses are becoming a growing concern in veterinary and public health. To date there are no registered vaccines against astrovirus-induced disease, mostly due to the difficulty to cultivate astroviruses to high titer for vaccine development using conventional techniques. As means to circumvent this drawback, we have developed stably transfected mink fetal cells and BHK21 cells constitutively expressing the full-length and truncated capsid proteins of two distinct genotypes of mink astrovirus. Protein expression in these stably transfected cells was demonstrated by strong signals as evaluated by in-situ PLA and IFA, and confirmed by Western blotting. The recombinant full-length and truncated proteins induced a high level of antibodies in mink, evaluated by ELISA, demonstrating their immunogenicity. In a challenge experiment in mink, a reduction in presentation clinical signs and virus shedding was observed in mink kits born from immunized females. The gene integration and protein expression were sustained through cell passage, showing that the used approach is robust and reliable for expression of functional capsid proteins for vaccine and diagnostic applications.


Assuntos
Anticorpos Antivirais/biossíntese , Infecções por Astroviridae/prevenção & controle , Infecções por Astroviridae/veterinária , Astroviridae/imunologia , Proteínas do Capsídeo/imunologia , Vison/imunologia , Animais , Anticorpos Antivirais/sangue , Astroviridae/genética , Infecções por Astroviridae/imunologia , Infecções por Astroviridae/virologia , Proteínas do Capsídeo/administração & dosagem , Proteínas do Capsídeo/genética , Linhagem Celular , Cricetinae , Feminino , Feto , Efeito Fundador , Expressão Gênica , Imunidade Ativa , Vison/virologia , Proteínas Recombinantes/administração & dosagem , Proteínas Recombinantes/genética , Proteínas Recombinantes/imunologia , Transfecção
19.
Can J Vet Res ; 77(3): 199-204, 2013 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-24101796

RESUMO

Hemorrhagic pneumonia can be a major cause of mortality in farmed mink in the fall. In its classic form, hemorrhagic pneumonia is caused by the bacterium Pseudomonas aeruginosa. In recent years, however, outbreaks of this type of pneumonia that are associated with hemolytic Escherichia coli have also occurred in farmed mink. The purpose of this study was to compare histological lesions of acute hemorrhagic pneumonia associated with both P. aeruginosa and E. coli in mink, including a description of tissue distribution of pathogens, in an attempt to differentiate between the 2 disease entities based on histopathology. The study included material submitted for diagnostic investigation to the National Veterinary Institute in Denmark from 2006 to 2009. Altogether, 19 cases of hemorrhagic pneumonia with a pure lung culture of P. aeruginosa and 18 cases of hemorrhagic pneumonia with a pure lung culture of E. coli were examined. Formalin-fixed paraffin-embedded lung tissue obtained from the mink was examined by histology and fluorescence in-situ hybridization (FISH). It was possible to detect a slight histological difference between hemorrhagic pneumonia caused by P. aeruginosa and by E. coli, as P. aeruginosa was most often found surrounding blood vessels and lining the alveoli, while E. coli showed a more diffuse distribution in the lung tissue. Furthermore, P. aeruginosa often elicited a very hemorrhagic response in the lung, while infection with E. coli was associated with a higher frequency of alveolar edema and mild lymphoid cuffing in the lungs.


Assuntos
Infecções por Escherichia coli/veterinária , Escherichia coli/imunologia , Vison/microbiologia , Pneumonia/veterinária , Infecções por Pseudomonas/veterinária , Pseudomonas aeruginosa/imunologia , Animais , DNA Bacteriano/química , DNA Bacteriano/genética , Dinamarca , Surtos de Doenças/veterinária , Escherichia coli/genética , Infecções por Escherichia coli/imunologia , Infecções por Escherichia coli/microbiologia , Histocitoquímica/veterinária , Hibridização in Situ Fluorescente/veterinária , Pulmão/imunologia , Pulmão/microbiologia , Pulmão/patologia , Vison/imunologia , Pneumonia/imunologia , Pneumonia/microbiologia , Reação em Cadeia da Polimerase/veterinária , Infecções por Pseudomonas/imunologia , Infecções por Pseudomonas/microbiologia , Pseudomonas aeruginosa/genética
20.
Can J Vet Res ; 77(3): 221-5, 2013 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-24101800

RESUMO

Hemorrhagic pneumonia is an acute and fatal disease of farmed mink caused by Pseudomonas aeruginosa. The pathogenesis of this disease has not yet been resolved. Mink are the only animals known to be susceptible to acute, contagious, and fatal lung infections caused by P. aeruginosa. The purpose of this study was to investigate the correlation between dose-response and season of infection and to clarify whether Danish mink are carriers of P. aeruginosa on their nasal mucosa during the season for hemorrhagic pneumonia. To elucidate the pathogenesis of the disease, an infectious dose-response trial was carried out on adult mink and mink kits, both in the season for hemorrhagic pneumonia (November) as well as out of season (July). It proved difficult to infect mink via the intra-nasal route. Only 4 out of 60 infected mink developed clinical disease and were euthanized, all of them in November, illustrating that predisposing factors in the mink itself and not infectious dose might be crucial for disease development. We were able to culture P. aeruginosa from the nasal cavity of the clinically healthy experimental mink 8 d after inoculation. This indicated that the mink can carry P. aeruginosa on their nasal mucosa without developing the disease. It was not possible, however, to culture P. aeruginosa from the nasal cavity of clinically healthy mink obtained from farms in November, which indicates that the organism is not a normal part of the nasal mucosal flora of mink.


Assuntos
Portador Sadio/veterinária , Hemorragia/veterinária , Vison/microbiologia , Pneumonia/veterinária , Infecções por Pseudomonas/veterinária , Pseudomonas aeruginosa/imunologia , Animais , Portador Sadio/imunologia , Portador Sadio/virologia , Dinamarca , Feminino , Masculino , Vison/imunologia , Mucosa Nasal/virologia , Pneumonia/imunologia , Pneumonia/virologia , Infecções por Pseudomonas/imunologia , Infecções por Pseudomonas/virologia , Estações do Ano
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