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1.
Viral Immunol ; 34(1): 3-17, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-32315582

RESUMEN

The parvoviruses are small nonenveloped single stranded DNA viruses that constitute members that range from apathogenic to pathogenic in humans and animals. The infection with a parvovirus results in the generation of antibodies against the viral capsid by the host immune system to eliminate the virus and to prevent re-infection. For members currently either being developed as delivery vectors for gene therapy applications or as oncolytic biologics for tumor therapy, efforts are aimed at combating the detrimental effects of pre-existing or post-treatment antibodies that can eliminate therapeutic benefits. Therefore, understanding antigenic epitopes of parvoviruses can provide crucial information for the development of vaccination applications and engineering novel capsids able to escape antibody recognition. This review aims to capture the information for the binding regions of ∼30 capsid-antibody complex structures of different parvovirus capsids determined to date by cryo-electron microscopy and three-dimensional image reconstruction. The comparison of all complex structures revealed the conservation of antigenic regions among parvoviruses from different genera despite low sequence identity and indicates that the available data can be used across the family for vaccine development and capsid engineering.


Asunto(s)
Anticuerpos Antivirales/química , Anticuerpos Antivirales/inmunología , Proteínas de la Cápside , Cápside/química , Cápside/inmunología , Epítopos , Parvovirus/química , Parvovirus/inmunología , Animales , Proteínas de la Cápside/química , Proteínas de la Cápside/inmunología , Microscopía por Crioelectrón , Epítopos/química , Epítopos/inmunología , Humanos , Parvovirus/clasificación , Desarrollo de Vacunas
2.
J Virol ; 94(4)2020 01 31.
Artículo en Inglés | MEDLINE | ID: mdl-31748386

RESUMEN

Parvoviruses are an important platform for gene and cancer therapy. Their cell entry and the following steps, including nuclear import, are inefficient, limiting their use in therapeutic applications. Two models exist on parvoviral nuclear entry: the classical import of the viral capsid using nuclear transport receptors of the importin (karyopherin) family or the direct attachment of the capsid to the nuclear pore complex leading to the local disintegration of the nuclear envelope. Here, by laser scanning confocal microscopy and in situ proximity ligation analyses combined with coimmunoprecipitation, we show that infection requires importin ß-mediated access to the nuclear pore complex and nucleoporin 153-mediated interactions on the nuclear side. The importin ß-capsid interaction continued within the nucleoplasm, which suggests a mixed model of nuclear entry in which the classical nuclear import across the nuclear pore complex is accompanied by transient ruptures of the nuclear envelope, also allowing the passive entry of importin ß-capsid complexes into the nucleus.IMPORTANCE Parvoviruses are small DNA viruses that deliver their DNA into the postmitotic nuclei, which is an important step for parvoviral gene and cancer therapies. Limitations in virus-receptor interactions or endocytic entry do not fully explain the low transduction/infection efficiency, indicating a bottleneck after virus entry into the cytoplasm. We thus investigated the transfer of parvovirus capsids from the cytoplasm to the nucleus, showing that the nuclear import of the parvovirus capsid follows a unique strategy, which differs from classical nuclear import and those of other viruses.


Asunto(s)
Infecciones por Parvoviridae/metabolismo , Parvovirus/metabolismo , beta Carioferinas/metabolismo , Transporte Activo de Núcleo Celular , Animales , Cápside/metabolismo , Proteínas de la Cápside/genética , Línea Celular , Núcleo Celular/virología , Citoplasma/metabolismo , Citosol/metabolismo , Carioferinas/metabolismo , Membrana Nuclear/metabolismo , Poro Nuclear/metabolismo , Parvovirus/inmunología , Internalización del Virus , Replicación Viral , alfa Carioferinas/metabolismo
3.
Emerg Infect Dis ; 24(7): 1292-1299, 2018 07.
Artículo en Inglés | MEDLINE | ID: mdl-29912685

RESUMEN

Development of next-generation sequencing and metagenomics has revolutionized detection of novel viruses. Among these viruses are 3 human protoparvoviruses: bufavirus, tusavirus, and cutavirus. These viruses have been detected in feces of children with diarrhea. In addition, cutavirus has been detected in skin biopsy specimens of cutaneous T-cell lymphoma patients in France and in 1 melanoma patient in Denmark. We studied seroprevalences of IgG against bufavirus, tusavirus, and cutavirus in various populations (n = 840), and found a striking geographic difference in prevalence of bufavirus IgG. Although prevalence was low in adult populations in Finland (1.9%) and the United States (3.6%), bufavirus IgG was highly prevalent in populations in Iraq (84.8%), Iran (56.1%), and Kenya (72.3%). Conversely, cutavirus IgG showed evenly low prevalences (0%-5.6%) in all cohorts, and tusavirus IgG was not detected. These results provide new insights on the global distribution and endemic areas of protoparvoviruses.


Asunto(s)
Infecciones por Parvoviridae/epidemiología , Infecciones por Parvoviridae/virología , Parvovirus , Adulto , Factores de Edad , Anciano , Anciano de 80 o más Años , Anticuerpos Antivirales/inmunología , Reacciones Cruzadas/inmunología , Femenino , Salud Global , Humanos , Inmunoglobulina G/inmunología , Masculino , Persona de Mediana Edad , Infecciones por Parvoviridae/inmunología , Parvovirus/clasificación , Parvovirus/genética , Parvovirus/inmunología , Vigilancia de la Población , Adulto Joven
4.
J Endocrinol ; 238(1): 61-75, 2018 07.
Artículo en Inglés | MEDLINE | ID: mdl-29743341

RESUMEN

The etiopathogenesis of type 1 diabetes (T1D) remains poorly understood. We used the LEW1.WR1 rat model of Kilham rat virus (KRV)-induced T1D to better understand the role of the innate immune system in the mechanism of virus-induced disease. We observed that infection with KRV results in cell influx into visceral adipose tissue soon following infection prior to insulitis and hyperglycemia. In sharp contrast, subcutaneous adipose tissue is free of cellular infiltration, whereas ß cell inflammation and diabetes are observed beginning on day 14 post infection. Immunofluorescence studies further demonstrate that KRV triggers CD68+ macrophage recruitment and the expression of KRV transcripts and proinflammatory cytokines and chemokines in visceral adipose tissue. Adipocytes from naive rats cultured in the presence of KRV express virus transcripts and upregulate cytokine and chemokine gene expression. KRV induces apoptosis in visceral adipose tissue in vivo, which is reflected by positive TUNEL staining and the expression of cleaved caspase-3. Moreover, KRV leads to an oxidative stress response and downregulates the expression of adipokines and genes associated with mediating insulin signaling. Activation of innate immunity with Poly I:C in the absence of KRV leads to CD68+ macrophage recruitment to visceral adipose tissue and a decrease in adipokine expression detected 5 days following Poly (I:C) treatment. Finally, proof-of-principle studies show that brief anti-inflammatory steroid therapy suppresses visceral adipose tissue inflammation and protects from virus-induced disease. Our studies provide evidence raising the hypothesis that visceral adipose tissue inflammation and dysfunction may be involved in early mechanisms triggering ß cell autoimmunity.


Asunto(s)
Tejido Adiposo/patología , Tejido Adiposo/fisiopatología , Diabetes Mellitus Tipo 1/virología , Inflamación/complicaciones , Paniculitis/complicaciones , Parvovirus/fisiología , Tejido Adiposo/inmunología , Tejido Adiposo/virología , Animales , Células Cultivadas , Diabetes Mellitus Tipo 1/inmunología , Diabetes Mellitus Tipo 1/patología , Diabetes Mellitus Tipo 1/fisiopatología , Femenino , Inmunidad Innata/fisiología , Inflamación/patología , Inflamación/virología , Macrófagos/fisiología , Masculino , Paniculitis/inmunología , Paniculitis/patología , Paniculitis/virología , Parvovirus/inmunología , Ratas , Transducción de Señal/inmunología
5.
Appl Biochem Biotechnol ; 179(4): 531-44, 2016 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-26879976

RESUMEN

CD8 molecule is a key marker on T cell surface and is connected with the antigen recognition and activation of T lymphocytes. In order to provide a detection method for quantifying goose CD8α expression, this study raised the protein and antibody for goose CD8α and developed a feasible cell marker enzyme-linked immunoabsorbent assay (ELISA) method. Recombinant protein of the extracellular region gene of goCD8α was expressed in prokaryotic expression system, and specific polyclonal antibodies for goCD8α were raised and purified, which was further confirmed by Western-blot, immunofluorescence assay (IFA), and immunohistochemistry (IHC). A cell marker ELISA was established and optimized to detect the change of goCD8α expression between goose parvovirus (GPV)-infected and mock-infected goose peripheral blood mononuclear cells (PBMCs), which is consistent with our previously results of real-time quantitative PCR (qPCR). Cell marker ELISA can provide a new method to detect goCD8α in protein level and in a sensitive, specific, and simple way. This may provide a convenient and novel method for the detection of goCD8α expression.


Asunto(s)
Antígenos de Superficie/aislamiento & purificación , Antígenos CD8/aislamiento & purificación , Ensayo de Inmunoadsorción Enzimática/métodos , Miembro 7 de la Superfamilia de Receptores de Factores de Necrosis Tumoral/aislamiento & purificación , Animales , Anticuerpos Antivirales/inmunología , Antígenos de Superficie/genética , Antígenos CD8/genética , Antígenos CD8/inmunología , Gansos/genética , Gansos/inmunología , Leucocitos Mononucleares/inmunología , Parvovirus/inmunología , Reacción en Cadena en Tiempo Real de la Polimerasa/métodos , Linfocitos T/inmunología , Miembro 7 de la Superfamilia de Receptores de Factores de Necrosis Tumoral/genética , Miembro 7 de la Superfamilia de Receptores de Factores de Necrosis Tumoral/inmunología
6.
J Virol ; 88(9): 4932-42, 2014 May.
Artículo en Inglés | MEDLINE | ID: mdl-24554651

RESUMEN

UNLABELLED: Members of the genus Parvovirus are small, nonenveloped single-stranded DNA viruses that are nonpathogenic in humans but have potential utility as cancer therapeutics. Because the innate immune response to parvoviruses has received relatively little attention, we compared the response to parvoviruses to that of several other types of viruses in human cells. In normal human glia, fibroblasts, or melanocytes, vesicular stomatitis virus evoked robust beta interferon (IFN-ß) responses. Cytomegalovirus, pseudorabies virus, and Sindbis virus all evoked a 2-log-unit or greater upregulation of IFN-ß in glia; in contrast, LuIII and MVMp parvoviruses did not evoke a detectable IFN-ß or interferon-stimulated gene (ISG; MX1, oligoadenylate synthetase [OAS], IFIT-1) response in the same cell types. The lack of response raised the question of whether parvoviral infection can be attenuated by IFN; interestingly, we found that IFN did not decrease parvovirus (MVMp, LuIII, and H-1) infectivity in normal human glia, fibroblasts, or melanocytes. The same was true in human cancers, including glioma, sarcoma, and melanoma. Similarly, IFN failed to attenuate transduction by the dependovirus vector adeno-associated virus type 2. Progeny production of parvoviruses was also unimpaired by IFN in both glioma and melanoma, whereas vesicular stomatitis virus replication was blocked. Sarcoma cells with upregulated IFN signaling that show high levels of resistance to other viruses showed strong infection by LuIII. Unlike many other oncolytic viruses, we found no evidence that impairment of innate immunity in cancer cells plays a role in the oncoselectivity of parvoviruses in human cells. Parvoviral resistance to the effects of IFN in cancer cells may constitute an advantage in the virotherapy of some tumors. IMPORTANCE: Understanding the interactions between oncolytic viruses and the innate immune system will facilitate employing these viruses as therapeutic agents in cancer patients. The cancer-selective nature of some oncolytic viruses is based on the impaired innate immunity of many cancer cells. The parvoviruses H-1, LuIII, and MVM target cancer cells; however, their relationship with the innate immune system is relatively uncharacterized. Surprisingly, we found that these parvoviruses do not evoke an interferon response in normal human fibroblasts, glia, or melanocytes. Furthermore, unlike most other types of virus, we found that parvovirus infectivity is unaffected by interferon treatment of human normal or tumor cells. Finally, parvoviral replication was unimpaired by interferon in four human tumor types, including those with residual interferon functionality. We conclude that deficits in the interferon antiviral response of cancer cells do not contribute to parvoviral oncoselectivity in human cells. The interferon-resistant phenotype of parvoviruses may give them an advantage over interferon-sensitive oncolytic viruses in tumors showing residual interferon functionality.


Asunto(s)
Interferón Tipo I/inmunología , Parvovirus/inmunología , Línea Celular , Fibroblastos/inmunología , Fibroblastos/virología , Perfilación de la Expresión Génica , Humanos , Melanocitos/inmunología , Melanocitos/virología , Neuroglía/inmunología , Neuroglía/virología
7.
PLoS Pathog ; 9(9): e1003605, 2013 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-24068925

RESUMEN

Progeny particles of non-enveloped lytic parvoviruses were previously shown to be actively transported to the cell periphery through vesicles in a gelsolin-dependent manner. This process involves rearrangement and destruction of actin filaments, while microtubules become protected throughout the infection. Here the focus is on the intracellular egress pathway, as well as its impact on the properties and release of progeny virions. By colocalization with cellular marker proteins and specific modulation of the pathways through over-expression of variant effector genes transduced by recombinant adeno-associated virus vectors, we show that progeny PV particles become engulfed into COPII-vesicles in the endoplasmic reticulum (ER) and are transported through the Golgi to the plasma membrane. Besides known factors like sar1, sec24, rab1, the ERM family proteins, radixin and moesin play (an) essential role(s) in the formation/loading and targeting of virus-containing COPII-vesicles. These proteins also contribute to the transport through ER and Golgi of the well described analogue of cellular proteins, the secreted Gaussia luciferase in absence of virus infection. It is therefore likely that radixin and moesin also serve for a more general function in cellular exocytosis. Finally, parvovirus egress via ER and Golgi appears to be necessary for virions to gain full infectivity through post-assembly modifications (e.g. phosphorylation). While not being absolutely required for cytolysis and progeny virus release, vesicular transport of parvoviruses through ER and Golgi significantly accelerates these processes pointing to a regulatory role of this transport pathway.


Asunto(s)
Linfocitos B/virología , Retículo Endoplásmico/virología , Aparato de Golgi/virología , Interacciones Huésped-Patógeno , Parvovirus/fisiología , Virión/fisiología , Ensamble de Virus , Sustitución de Aminoácidos , Animales , Linfocitos B/inmunología , Linfocitos B/metabolismo , Linfocitos B/ultraestructura , Transporte Biológico , Proteínas de la Cápside/metabolismo , Efecto Citopatogénico Viral , Proteínas del Citoesqueleto/genética , Proteínas del Citoesqueleto/metabolismo , Retículo Endoplásmico/metabolismo , Retículo Endoplásmico/ultraestructura , Aparato de Golgi/metabolismo , Aparato de Golgi/ultraestructura , Hibridomas , Proteínas de la Membrana/genética , Proteínas de la Membrana/metabolismo , Ratones , Proteínas de Microfilamentos/genética , Proteínas de Microfilamentos/metabolismo , Mutación , Infecciones por Parvoviridae/inmunología , Infecciones por Parvoviridae/metabolismo , Infecciones por Parvoviridae/patología , Infecciones por Parvoviridae/virología , Parvovirus/inmunología , Parvovirus/ultraestructura , Fosforilación , Procesamiento Proteico-Postraduccional , Proteínas Recombinantes/metabolismo , Virión/inmunología , Virión/ultraestructura , Liberación del Virus
8.
Transfusion ; 53(10 Pt 2): 2575-84, 2013 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-23721256

RESUMEN

BACKGROUND: Human parvovirus 4 (ParV4), a newly described member of the family Parvoviridae, like B19V, has been found in pooled plasma preparations. The extent, and significance, of ParV4 exposure in UK blood donors remain to be determined and reliable detection of ParV4 immunoglobulin (Ig)G, using validated methods, is needed. STUDY DESIGN AND METHODS: With ParV4 virus-like particles a ParV4 IgG time-resolved fluorescence immunoassay (TRFIA) was developed. There is no gold standard or reference assay for measuring ParV4 IgG and the utility of the TRFIA was first examined using a panel of sera from people who inject drugs (PWIDS)--a high-prevalence population for ParV4 infection. Western blotting was used to confirm the specificity of TRFIA-reactive sera. Two cohorts of UK blood donor sera comprising 452 sera collected in 1999 and 156 sera collected in 2009 were tested for ParV4 IgG. Additional testing for B19V IgG, hepatitis C virus antibodies (anti-HCV), and ParV4 DNA was also undertaken. RESULTS: The rate of ParV4 IgG seroprevalence in PWIDS was 20.7% and ParV4 IgG was positively associated with the presence of anti-HCV with 68.4% ParV4 IgG-positive sera testing anti-HCV-positive versus 17.1% ParV4 IgG-negative sera. Overall seropositivity for ParV4 IgG, in 608 UK blood donors was 4.76%. The ParV4 IgG seropositivity for sera collected in 1999 was 5.08%, compared to 3.84% for sera collected in 2009. No ParV4 IgG-positive blood donor sera had detectable ParV4 DNA. CONCLUSION: ParV4 IgG has been found in UK blood donors and this finding needs further investigation.


Asunto(s)
Donantes de Sangre , Fluoroinmunoensayo , Tamizaje Masivo/métodos , Infecciones por Parvoviridae/diagnóstico , Parvovirus/aislamiento & purificación , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Animales , Anticuerpos Antivirales/sangre , Western Blotting , Humanos , Persona de Mediana Edad , Infecciones por Parvoviridae/sangre , Infecciones por Parvoviridae/epidemiología , Parvovirus/genética , Parvovirus/inmunología , Reacción en Cadena de la Polimerasa/métodos , Estudios Seroepidemiológicos , Células Sf9 , Reino Unido/epidemiología , Adulto Joven
9.
J Med Virol ; 84(8): 1267-73, 2012 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-22711355

RESUMEN

Human bocaviruses 1-4 (HBoV1-4) and parvovirus 4 (PARV4) are recently discovered human parvoviruses. HBoV1 is associated with respiratory infections of young children, while HBoV2-4 are enteric viruses. The clinical manifestations of PARV4 remain unknown. The objective of this study was to determine whether the DNAs of HBoV1-4 and PARV4 persist in human tissues long after primary infection. Biopsies of tonsillar tissue, skin, and synovia were examined for HBoV1-4 DNA and PARV4 DNA by PCR. Serum samples from the tissue donors were assayed for HBoV1 and PARV4 IgG and IgM antibodies. To obtain species-specific seroprevalences for HBoV1 and for HBoV2/3 combined, the sera were analyzed after virus-like particle (VLP) competition. While HBoV1 DNA was detected exclusively in the tonsillar tissues of 16/438 individuals (3.7%), all of them ≤8 years of age. HBoV2-4 and PARV4 DNAs were absent from all tissue types. HBoV1 IgG seroprevalence was 94.9%. No subject had HBoV1 or PARV4 IgM, nor did they have PARV4 IgG. The results indicate that HBoV1 DNA occurred in a small proportion of tonsils of young children after recent primary HBoV1 infection, but did not persist long in the other tissue types studied, unlike parvovirus B19 DNA. The results obtained by the PARV4 assays are in line with previous results on PARV4 epidemiology.


Asunto(s)
Bocavirus Humano/aislamiento & purificación , Tonsila Palatina/virología , Infecciones por Parvoviridae/epidemiología , Parvovirus/aislamiento & purificación , Piel/virología , Líquido Sinovial/virología , Adolescente , Adulto , Anciano , Biopsia , Niño , Preescolar , ADN Viral/análisis , Bocavirus Humano/genética , Bocavirus Humano/inmunología , Humanos , Inmunoglobulina G/sangre , Inmunoglobulina M/sangre , Lactante , Persona de Mediana Edad , Infecciones por Parvoviridae/inmunología , Infecciones por Parvoviridae/virología , Parvovirus/genética , Parvovirus/inmunología , Reacción en Cadena de la Polimerasa , Especificidad de la Especie , Tonsilitis/epidemiología , Tonsilitis/inmunología , Tonsilitis/virología , Adulto Joven
10.
Hybridoma (Larchmt) ; 31(2): 125-30, 2012 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-22509917

RESUMEN

In the present study, monoclonal antibodies (MAbs) against NS1 protein of Goose parvovirus (GPV) were generated. The secreted MAbs were obtained by fusing mouse myeloma cells and spleen cells of BALB/c mice, which were immunized with the plasmid pcDNA3.1-GPV-NS1 and recombinant protein of GPV-NS1. With indirect ELISA, six hybridoma cell lines against GPV-NS1 were screened. The subtypes of the two MAbs were IgG2a; the others were IgM. The light chain was κ. Western blot analysis showed that six MAbs reacted with recombinant protein GPV-NS1. GPV-NS1 was dissected into 15 overlapping epitopes, which were used to react with MAbs in Western blot. Results showed that six MAbs recognized NS1 protein linear B-cell epitopes located at the C-terminus 453-514 aa, 485-542 aa, and 533-598 aa.


Asunto(s)
Anticuerpos Monoclonales/inmunología , Gansos , Infecciones por Parvoviridae/veterinaria , Parvovirus/inmunología , Enfermedades de las Aves de Corral/virología , Proteínas Recombinantes/inmunología , Proteínas no Estructurales Virales/inmunología , Animales , Anticuerpos Monoclonales/biosíntesis , Anticuerpos Antivirales/inmunología , Especificidad de Anticuerpos/inmunología , Línea Celular , Epítopos/inmunología , Femenino , Ratones , Ratones Endogámicos BALB C , Infecciones por Parvoviridae/virología , Proteínas Recombinantes/biosíntesis , Proteínas Recombinantes/genética , Proteínas Recombinantes/aislamiento & purificación , Proteínas no Estructurales Virales/genética , Proteínas no Estructurales Virales/metabolismo
11.
Vet Immunol Immunopathol ; 145(1-2): 522-6, 2012 Jan 15.
Artículo en Inglés | MEDLINE | ID: mdl-22209204

RESUMEN

Goose parvovirus (GPV), a small non-enveloped ssDNA virus, can cause Derzsy's disease, a highly contagious and lethal disease in goslings and muscovy ducklings, leading to a huge economic loss. However, little is known about the localization of B-cell epitopes on GPV structural protein. To address the issue, the structural protein of GPV was dissected into sets of partially overlapping fragments and expressed in Escherichia coli. Then Western blot reactivity of these glutathione S-transferase (GST) fusion short peptides to viral infected sera was surveyed. The results showed linear immunodominant epitopes, which were found in seven fragments covering amino acid residues 35-71, 123-198, 423-444, 474-491, 531-566, 616-669, 678-732. Our findings may provide the basis for the development of immunity-based prophylactic, therapeutic, and diagnostic clinical techniques for Derzsy's disease.


Asunto(s)
Epítopos de Linfocito B/inmunología , Gansos/virología , Infecciones por Parvoviridae/veterinaria , Parvovirus/inmunología , Enfermedades de las Aves de Corral/virología , Proteínas Estructurales Virales/inmunología , Secuencia de Aminoácidos , Animales , Western Blotting/veterinaria , Mapeo Epitopo/veterinaria , Gansos/inmunología , Datos de Secuencia Molecular , Infecciones por Parvoviridae/inmunología , Infecciones por Parvoviridae/virología , Parvovirus/ultraestructura , Enfermedades de las Aves de Corral/inmunología , Alineación de Secuencia/veterinaria , Proteínas Estructurales Virales/ultraestructura
12.
Autoimmunity ; 44(2): 137-48, 2011 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-20695765

RESUMEN

The adipokine, leptin, regulates blood glucose and the insulin secretory function of beta cells, while also modulating immune cell function. We hypothesized that the dual effects of leptin may prevent or suppress the autoreactive destruction of beta cells in a virally induced rodent model of type 1 diabetes. Nearly 100% of weanling BBDR rats treated with the combination of an innate immune system activator, polyinosinic:polycytidylic acid (pIC), and Kilham rat virus (KRV) become diabetic within a predictable time frame. We utilized this model to test the efficacy of leptin in preventing diabetes onset, remitting new onset disease, and preventing autoimmune recurrence in diabetic rats transplanted with syngeneic islet grafts. High doses of leptin delivered via an adenovirus vector (AdLeptin) or alzet pump prevented diabetes in>90% of rats treated with pIC+KRV. The serum hyperleptinemia generated by this treatment was associated with decreased body weight, decreased non-fasting serum insulin levels, and lack of islet insulitis in leptin-treated rats. In new onset diabetics, hyperleptinemia prevented rapid weight loss and diabetic ketoacidosis, and temporarily restored euglycemia. Leptin treatment also prolonged the survival of syngeneic islets transplanted into diabetic BBDR rats. In diverse therapeutic settings, we found leptin treatment to have significant beneficial effects in modulating virally induced diabetes. These findings merit further evaluation of leptin as a potential adjunct therapeutic agent for treatment of human type 1 diabetes.


Asunto(s)
Diabetes Mellitus Experimental/tratamiento farmacológico , Diabetes Mellitus Tipo 1/tratamiento farmacológico , Leptina/uso terapéutico , Infecciones por Parvoviridae/inmunología , Parvovirus/inmunología , Animales , Glucemia , Diabetes Mellitus Experimental/inmunología , Diabetes Mellitus Experimental/patología , Diabetes Mellitus Experimental/virología , Diabetes Mellitus Tipo 1/patología , Diabetes Mellitus Tipo 1/virología , Cetoacidosis Diabética/prevención & control , Humanos , Trasplante de Islotes Pancreáticos , Leptina/administración & dosificación , Leptina/inmunología , Infecciones por Parvoviridae/virología , Poli I-C/administración & dosificación , Poli I-C/inmunología , Ratas , Ratas Endogámicas BB , Resultado del Tratamiento
13.
Rev Argent Microbiol ; 42(1): 27-9, 2010.
Artículo en Inglés | MEDLINE | ID: mdl-20461290

RESUMEN

The Kilham rat virus (KRV) is a parvovirus originally isolated from a rat sarcoma in the late 1950s. The clinical signs associated with a natural KRV infection include foetal resorption in dams, runting, ataxia, cerebellar hypoplasia and jaundice in suckling rats, and sudden death, scrotal cyanosis, abdominal swelling and dehydration in juvenile rats. The ability of this virus to produce persistent infections has resulted in a high frequency of contamination of cell cultures and transplantable-tumor system. In addition, the virus may interfere with research in other ways. The remarkable resistance to environmental conditions determines the importance of the detection and control of this agent, especially in the laboratory animal production. This study determines the seroprevalence of Kilham antibodies from sera of adult rats from conventional facilities, using the haemagglutination inhibition test. The seroprevalence varied between 27.8% and 75%. This result confirms that the virus is circulating in Argentinean conventional facilities and might be interfering with research. The recognized Kilham virus may be prevented from supply sources by implementing a health monitoring schedule including a regular serological surveillance, and by keeping the animals under barrier systems.


Asunto(s)
Animales de Laboratorio/inmunología , Anticuerpos Antivirales/sangre , Infecciones por Parvoviridae/veterinaria , Parvovirus/inmunología , Ratas/inmunología , Enfermedades de los Roedores/epidemiología , Animales , Anticuerpos Antivirales/inmunología , Argentina/epidemiología , Pruebas de Inhibición de Hemaglutinación , Infecciones por Parvoviridae/epidemiología , Infecciones por Parvoviridae/inmunología , Infecciones por Parvoviridae/virología , Enfermedades de los Roedores/inmunología , Enfermedades de los Roedores/virología , Estudios Seroepidemiológicos , Organismos Libres de Patógenos Específicos
14.
Arq. bras. med. vet. zootec ; 61(3): 752-754, jun. 2009. tab
Artículo en Inglés | LILACS | ID: lil-519472

RESUMEN

A ocorrência da infecção por coronavírus felino (FCoV), herpesvírus felino tipo 1 (FHV-1), calicivírus felino (FCV) e parvovírus felino (FPV) foi investigada mediante a detecção de anticorpos no soro de 97 gatos domésticos de Pelotas, RS, pelo teste de soro-neutralização. Entre os animais estudados, 51 não eram vacinados, 11 haviam sido vacinados contra FHV-1, FCV e FPV com pelo menos uma dose, e 35 tinham histórico de vacinação desconhecido. Foram detectados anticorpos para o FCoV em 75,2% (73/97) dos gatos. Anticorpos contra o FHV-1 estavam presentes em 38,1% (37/97): 73% (8/11) dos gatos vacinados, 39,2% (20/51) dos não vacinados e 25,7% (9/35) dos gatos com histórico de vacinação desconhecido. Anticorpos para o FCV estavam presentes em 56,7% (55/97): 81,8% (9/11) dos gatos vacinados, 52,9% (27/51) dos não vacinados, e 54,3% (19/35) dos gatos com histórico de vacinação desconhecido. Para o FPV, havia anticorpos em 69,1% (67/97): 100% (11/11) dos vacinados, 66,6% (34/51) dos não vacinados e 62,8% (22/35) dos gatos com histórico de vacinação desconhecido. Os resultados sugerem alta exposição ao FCoV, FHV-1, FCV e FPV na população de gatos na área estudada.


Asunto(s)
Animales , Masculino , Femenino , Anticuerpos Antivirales/aislamiento & purificación , Anticuerpos Antivirales/sangre , Calicivirus Felino/inmunología , Coronavirus Felino/inmunología , Gatos/inmunología , Herpesviridae/inmunología , Parvovirus/inmunología
16.
J Feline Med Surg ; 10(3): 247-51, 2008 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-18243743

RESUMEN

In-house tests for the identification of faecal parvovirus antigen are now available. The majority of these are licensed for canine parvovirus only; but anecdotal information suggests that they will detect feline panleukopenia virus (FPV) as well. This prospective study was designed to compare five commercially available test systems. In total, 200 faecal samples from randomly selected healthy cats (148) and cats with diarrhoea (52) were tested and compared with the results of examination by electron microscopy. Ten cats were positive for FPV and all of these had diarrhoea. In-house canine parvovirus tests can be used to detect FPV. All tests were suitable to screen cats for faecal parvovirus excretion (positive predictive values for the Witness Parvo, the Snap Parvo, the SAS Parvo, the Fastest Parvo Strip, and the Speed Parvo were 100.0, 100.0, 57.1, 38.9, and 100%, respectively, negative predictive values for the Witness Parvo, the Snap Parvo, the SAS Parvo, the Fastest Parvo Strip, and the Speed Parvo were 97.4, 97.9, 98.9, 98.4, and 97.4%, respectively). In-house parvovirus tests may be positive up to 2 weeks after vaccination, and therefore, in recently vaccinated cats positive results do not necessarily mean infection.


Asunto(s)
Diarrea/veterinaria , Virus de la Panleucopenia Felina/inmunología , Infecciones por Parvoviridae/veterinaria , Parvovirus Canino/inmunología , Animales , Antígenos Virales , Gatos , Diarrea/microbiología , Heces/virología , Panleucopenia Felina/inmunología , Femenino , Alemania , Masculino , Parvovirus/inmunología , Estudios Prospectivos , Sensibilidad y Especificidad , Vacunas Virales/inmunología
17.
Immunology ; 124(1): 68-75, 2008 May.
Artículo en Inglés | MEDLINE | ID: mdl-18034821

RESUMEN

Lactobacillus casei ATCC 393 was selected as a bacterial carrier for the development of mucosal vaccine against porcine parvovirus (PPV) infection. The PPV major structural polypeptide VP2 was used as the model parvovirus antigen. Two inducible expression systems, namely pPG611.1 of the cell-surface expression system and pPG612.1 of the secretion expression system based on the xylose operon promoter were used to express the VP2 protein. The immunogenicity of recombinant strains producing VP2 protein in two cellular locations, cell-surface exposed and secreted, was compared to each other by immunizing mice through the intragastric administration. The two types of constructs were able to induce strong specific immune responses against VP2 via intragastric administration and maximum titres of IgA and IgG were attained on days 46 post oral immunization, while the highest antibody levels were obtained with the strain producing the VP2 protein in extracellular milieu. The induced antibodies demonstrated neutralizing effects on PPV infection.


Asunto(s)
Antígenos Virales/inmunología , Proteínas de la Cápside/inmunología , Lacticaseibacillus casei/genética , Infecciones por Parvoviridae/inmunología , Parvovirus/inmunología , Vacunas Virales/inmunología , Administración Oral , Animales , Anticuerpos Antivirales/biosíntesis , Vectores Genéticos , Inmunidad Mucosa , Inmunización/métodos , Inmunoglobulina A/biosíntesis , Inmunoglobulina G/biosíntesis , Lacticaseibacillus casei/inmunología , Ratones , Ratones Endogámicos BALB C , Proteínas Recombinantes/inmunología , Vacunas Sintéticas/inmunología
18.
Eur J Immunol ; 37(6): 1485-93, 2007 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-17506032

RESUMEN

The ability of human keratinocytes to present antigen to T cells is controversial and, indeed, it has been suggested that keratinocytes may promote T cell hyporesponsiveness. Furthermore, it is unclear whether keratinocytes can process antigen prior to MHC class I and class II presentation. We tested the ability of keratinocytes to induce functional responses in epitope-specific CD4+ and CD8+ memory T cells using peptides, protein and recombinant expression vectors as sources of antigen. Keratinocytes were able to efficiently process and present protein antigen to CD4+ T cells, resulting in cytokine secretion (Th1 and Th2). This interaction was dependent on keratinocyte expression of HLA class II and ICAM-1, which could be induced by IFN-gamma. In addition, keratinocytes could present virally encoded or exogenous peptide to CD8+ T cells, resulting in T cell cytokine production and target cell lysis. Finally, T cell lines grown using keratinocytes as stimulators showed no loss of function. These findings demonstrate that keratinocytes are able to efficiently process and present antigen to CD4+ and CD8+ memory T cells and induce functional responses. The findings have broad implications for the pathogenesis of cutaneous disease and for transcutaneous drug or vaccine delivery.


Asunto(s)
Presentación de Antígeno/inmunología , Linfocitos T CD4-Positivos/inmunología , Linfocitos T CD8-positivos/inmunología , Queratinocitos/inmunología , Anticuerpos Monoclonales/inmunología , Anticuerpos Monoclonales/farmacología , Presentación de Antígeno/efectos de los fármacos , Antígenos Dermatofagoides/inmunología , Proteínas de Artrópodos , Linfocitos B/inmunología , Antígeno B7-1/metabolismo , Antígeno B7-2/metabolismo , Linfocitos T CD4-Positivos/citología , Linfocitos T CD4-Positivos/metabolismo , Linfocitos T CD8-positivos/citología , Linfocitos T CD8-positivos/metabolismo , Línea Celular , Línea Celular Transformada , Células Cultivadas , Cisteína Endopeptidasas , Citotoxicidad Inmunológica/efectos de los fármacos , Citotoxicidad Inmunológica/inmunología , Antígenos HLA-D/metabolismo , Antígenos de Histocompatibilidad Clase I/metabolismo , Humanos , Molécula 1 de Adhesión Intercelular/metabolismo , Interferón gamma/metabolismo , Interferón gamma/farmacología , Interleucina-4/metabolismo , Queratinocitos/citología , Queratinocitos/metabolismo , Antígeno-1 Asociado a Función de Linfocito/inmunología , Oligopéptidos/inmunología , Parvovirus/inmunología , Fosfoproteínas/inmunología , Receptores de Interferón/metabolismo , Transactivadores/inmunología , Proteínas Virales/inmunología , Receptor de Interferón gamma
19.
J Immunol ; 178(2): 693-701, 2007 Jan 15.
Artículo en Inglés | MEDLINE | ID: mdl-17202329

RESUMEN

Viral infections are associated epidemiologically with the expression of type 1 diabetes in humans, but the mechanisms underlying this putative association are unknown. To investigate the role of viruses in diabetes, we used a model of viral induction of autoimmune diabetes in genetically susceptible biobreeding diabetes-resistant (BBDR) rats. BBDR rats do not develop diabetes in viral-Ab-free environments, but approximately 25% of animals infected with the parvovirus Kilham rat virus (KRV) develop autoimmune diabetes via a mechanism that does not involve beta cell infection. Using this model, we recently documented that TLR agonists synergize with KRV infection and increase disease penetrance. We now report that KRV itself activates innate immunity through TLR ligation. We show that KRV infection strongly stimulates BBDR splenocytes to produce the proinflammatory cytokines IL-6 and IL-12p40 but not TNF-alpha. KRV infection induces high levels of IL-12p40 by splenic B cells and Flt-3-ligand-induced bone marrow-derived dendritic cells (DCs) but only low levels of IL-12p40 production by thioglycolate-elicited peritoneal macrophages or GM-CSF plus IL-4-induced bone marrow-derived DCs. KRV-induced cytokine production is blocked by pharmacological inhibitors of protein kinase R and NF-kappaB. Genomic KRV DNA also induces BBDR splenocytes and Flt-3L-induced DCs from wild-type but not TLR9-deficient mice to produce IL-12p40; KRV-induced up-regulation of B lymphocytes can be blocked by TLR9 antagonists including inhibitory CpG and chloroquine. Administration of chloroquine to virus-infected BBDR rats decreases the incidence of diabetes and decreases blood levels of IL-12p40. Our data implicate the TLR9-signaling pathway in KRV-induced innate immune activation and autoimmune diabetes in the BBDR rat.


Asunto(s)
Diabetes Mellitus Tipo 1/inmunología , Diabetes Mellitus Tipo 1/metabolismo , Salud , Parvovirus/inmunología , Transducción de Señal , Receptor Toll-Like 9/metabolismo , Animales , Linfocitos B/inmunología , Linfocitos B/metabolismo , Cruzamiento , Células Cultivadas , Cloroquina/farmacología , ADN Viral/genética , ADN Viral/aislamiento & purificación , Diabetes Mellitus Tipo 1/virología , Susceptibilidad a Enfermedades , Femenino , Genoma Viral/genética , Subunidad p40 de la Interleucina-12/biosíntesis , Subunidad p40 de la Interleucina-12/metabolismo , Interleucina-6/metabolismo , Macrófagos/metabolismo , Masculino , Proteínas de la Membrana/inmunología , Proteínas de la Membrana/metabolismo , FN-kappa B/metabolismo , Ratas , Bazo/efectos de los fármacos , Bazo/inmunología , Bazo/metabolismo , Receptor Toll-Like 9/deficiencia , Receptor Toll-Like 9/genética , Factor de Necrosis Tumoral alfa/metabolismo
20.
J Wildl Dis ; 42(2): 470-7, 2006 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-16870878

RESUMEN

Serum samples from 18 pumas (Puma concolor), one ocelot (Leopardus pardalis), and two little spotted cats (Leopardus tigrinus) collected from free-ranging animals in Brazil between 1998 and 2004 were tested by indirect immunofluorescence (IFA) for antibodies to feline herpesvirus 1 (FHV 1), calicivirus (FCV), coronavirus (FCoV), parvo-virus (FPV), Ehrlichia canis, Anaplasma pha-gocytophilum, and Bartonella henselae. Serum samples also were tested, by Western blot and ELISA, for feline leukemia virus (FeLV) specific antibodies and antigen, respectively, by Western blot for antibodies to feline immunodeficiency virus (FIV), and by indirect ELISA for antibodies to puma lentivirus (PLV). Antibodies to FHV 1, FCV, FCoV, FPV, FeLV, FIV, PLV or related viruses, and to B. henselae were detected. Furthermore, high-titered antibodies to E. canis or a closely related agent were detected in a puma for the first time.


Asunto(s)
Anticuerpos Antibacterianos/sangre , Anticuerpos Antivirales/sangre , Panthera/microbiología , Puma/microbiología , Animales , Animales Salvajes/microbiología , Animales Salvajes/virología , Western Blotting/veterinaria , Brasil/epidemiología , Calicivirus Felino/inmunología , Ehrlichia/inmunología , Técnica del Anticuerpo Fluorescente Indirecta/métodos , Técnica del Anticuerpo Fluorescente Indirecta/veterinaria , Herpesviridae/inmunología , Panthera/virología , Parvovirus/inmunología , Puma/virología , Estudios Seroepidemiológicos
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