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1.
Pathogens ; 12(7)2023 Jun 23.
Artículo en Inglés | MEDLINE | ID: mdl-37513714

RESUMEN

Influenza, a respiratory disease mainly caused by influenza A and B, viruses of the Orthomyxoviridae, is still a burden on our society's health and economic system. Influenza A viruses (IAV) circulate in mammalian and avian populations, causing seasonal outbreaks with high numbers of cases. Due to the high variability in seasonal IAV triggered by antigenic drift, annual vaccination is necessary, highlighting the need for a more broadly protective vaccine against IAV. The safety tested Modified Vaccinia virus Ankara (MVA) is licensed as a third-generation vaccine against smallpox and serves as a potent vector system for the development of new candidate vaccines against different pathogens. Here, we generated and characterized recombinant MVA candidate vaccines that deliver the highly conserved internal nucleoprotein (NP) of IAV under the transcriptional control of five newly designed chimeric poxviral promoters to further increase the immunogenic properties of the recombinant viruses (MVA-NP). Infections of avian cell cultures with the recombinant MVA-NPs demonstrated efficient synthesis of the IAV-NP which was expressed under the control of the five new promoters. Prime-boost or single shot immunizations in C57BL/6 mice readily induced circulating serum antibodies' binding to recombinant IAV-NP and the robust activation of IAV-NP-specific CD8+ T cell responses. Moreover, the MVA-NP candidate vaccines protected C57BL/6 mice against lethal respiratory infection with mouse-adapted IAV (A/Puerto Rico/8/1934/H1N1). Thus, further studies are warranted to evaluate the immunogenicity and efficacy of these recombinant MVA-NP vaccines in other IAV challenge models in more detail.

2.
Vet Pathol ; 59(2): 319-327, 2022 03.
Artículo en Inglés | MEDLINE | ID: mdl-34856834

RESUMEN

A new gene defect in Fleckvieh calves leads to a syndrome with partial phenotype overlap with bovine hereditary zinc deficiency. A mutation in a gene encoding phospholipase D4 (PLD4), an endosomal exonuclease, causes the disorder. In mice, PLD4 activity indirectly regulates the Toll-like receptor 9 (TLR9) pathway via degradation of microbial DNA. PLD4 absence thus results in visceral macrophage activation comparable to human macrophage activation syndrome. In this study, disease progression and the role of macrophages in affected calves were monitored clinically, clinicopathologically, and histologically over time. Breeding data identified 73 risk matings of heterozygous carriers resulting in 54 potentially PLD4-deficient calves born on farms. PLD4 status was examined via 5'-exonuclease assay, detecting 6 calves carrying the defect. These were purchased and monitored daily until final necropsy. The calves developed progressive skin lesions starting with small scaling areas terminating in severe crusting dermatitis, especially in areas with mechanical exposure. Histological and immunohistochemical analyses indicated that macrophages with cytoplasmic vacuolation increased considerably in skin sections obtained weekly during the disease course. Macrophage increase correlated with increased dermal lesion severity. Macrophage activation was confirmed by prominent phagocytic activity in the superficial dermis using electron microscopy. Dermal mRNA abundance of CCL2 and CCL3 measured by quantitative polymerase chain reaction verified macrophage activation. Further increase in mRNA of downstream molecule MyD88 and cytokine IL12b connected bovine PLD4 deficiency to increased TLR9 pathway activation. In contrast to human macrophage activation syndrome, the main feature of bovine PLD4 deficiency was local disease in organs with contact to microbial DNA (skin, intestine, lungs).


Asunto(s)
Enfermedades de los Bovinos , Síndrome de Activación Macrofágica , Fosfolipasa D , Enfermedades de los Roedores , Animales , Bovinos , Enfermedades de los Bovinos/patología , ADN , Progresión de la Enfermedad , Exonucleasas , Síndrome de Activación Macrofágica/veterinaria , Macrófagos/patología , Ratones , Fosfolipasa D/genética , Fosfolipasa D/metabolismo , Fosfolipasas , ARN Mensajero , Receptor Toll-Like 9/genética
3.
BMC Vet Res ; 15(1): 411, 2019 Nov 15.
Artículo en Inglés | MEDLINE | ID: mdl-31730460

RESUMEN

BACKGROUND: Alopecia is defined as the partial or complete absence of hair from areas of the body where it normally grows. Alopecia secondary to an infectious disease or parasitic infestation is commonly seen in cattle. It can also have metabolic causes, for example in newborn calves after a disease event such as diarrhoea. In the article, the investigation of a herd problem of acquired alopecia in Belgian Blue (BB) crossbred calves is described. CASE PRESENTATION: Several BB crossbred calves had presented with moderate to severe non-pruritic alopecia in a single small herd located in Southern Germany. The referring veterinarian had ruled out infectious causes, including parasitic infection and had supplemented calves with vitamins (vitamins A, B1, B2, B3, B5, B6, B7, B9, B12, C, and K3) orally. Results of the diagnostic workup at the Clinic for Ruminants are presented for three affected calves and findings from a farm visit are discussed. Because of these investigations, an additional four calves were brought to the referral clinic within the first week of life, and before onset of alopecia, in order to study the course of the condition; however, these calves never developed any signs of alopecia during their clinic stay. CONCLUSIONS: Because all other plausible differential diagnoses were ruled out during our investigation, we concluded that the documented alopecia was due to malabsorption of dietary fat and consecutive disruption of lipid metabolism leading to telogen or anagen effluvium. In this particular case, this was caused by a mixing error of milk replacer in conjunction with insufficiently tempered water. We conclude that nutritional, management or environmental factors alone can lead to moderate to severe alopecia in calves in the absence of a prior or concurrent disease event or infectious cause.


Asunto(s)
Alopecia/veterinaria , Enfermedades de los Bovinos/patología , Grasas de la Dieta/metabolismo , Sustitutos de la Leche/química , Alopecia/etiología , Alopecia/patología , Animales , Bovinos , Enfermedades de los Bovinos/etiología , Grasas de la Dieta/administración & dosificación , Grasas de la Dieta/análisis , Masculino
4.
Pathogens ; 8(4)2019 Oct 06.
Artículo en Inglés | MEDLINE | ID: mdl-31590460

RESUMEN

For many years, brown trout (Salmo trutta fario) mortalities within the pre-alpine Isar River in Germany were reported by the Bavarian Fisheries Association (Landesfischereiverband Bayern e.V.) and local recreational anglers during August and September. Moribund fish seemed to be affected by proliferative darkening syndrome (PDS). In addition, proliferative kidney disease (PKD) caused by Tetracapsuloides bryosalmonae was discussed. To investigate this phenomenon, the present field study monitored brown trout mortalities by daily river inspection in 2017 and 2018. Moribund brown trout (n = 31) were collected and examined using histology, immunohistochemistry, qPCR, and quantitative stereology. Our investigations identified 29 (93.5%) brown trout affected by PKD. Four brown trout (12.9%) displayed combined hepatic and splenic lesions fitting the pathology of PDS. The piscine orthoreovirus 3, suspected as causative agent of PDS, was not detectable in any of the samples. Quantitative stereological analysis of the kidneys revealed a significant increase of the renal tissue volumes with interstitial inflammation and hematopoietic hyperplasia in PKD-affected fish as compared to healthy brown trout. The identified T. bryosalmonae strain was classified as part of the North American clade by phylogenetical analysis. This study highlights PKD and PDS as contributing factors to recurrent autumnal brown trout mortalities.

5.
Future Microbiol ; 14: 275-282, 2019 03.
Artículo en Inglés | MEDLINE | ID: mdl-30757912

RESUMEN

AIM: Immunofluorescence microscopy is a powerful technique to detect surface antigens and study their distribution. Analysis of fungi is often hampered by their weak adherence to glass. We therefore established a novel immunofluorescence staining method to overcome this problem. MATERIALS & METHODS: Fungal material from colonies is bound to adhesive tape and stained with antibodies. RESULTS: The obtained samples had very good optical quality, showing low unspecific background staining and allowing analysis by confocal laser scanning microscopy. We have exemplified applying the new method to study the distribution of galactomannan on conidiophores of Aspergillus fumigatus and of ß-glucans on Malassezia pachydermatis. CONCLUSION: Tape mount immunostaining facilitates analysis of fungal surface molecules and provides a base for expeditious diagnostic procedures.


Asunto(s)
Aspergillus fumigatus/química , Técnica del Anticuerpo Fluorescente/métodos , Malassezia/química , Coloración y Etiquetado/métodos , Adhesivos/química , Aspergillus fumigatus/metabolismo , Técnica del Anticuerpo Fluorescente/instrumentación , Galactosa/análogos & derivados , Humanos , Malassezia/metabolismo , Mananos/metabolismo , Coloración y Etiquetado/instrumentación , beta-Glucanos/metabolismo
6.
Viruses ; 11(2)2019 01 28.
Artículo en Inglés | MEDLINE | ID: mdl-30696111

RESUMEN

The proliferative darkening syndrome (PDS) is a lethal disease of brown trout (Salmo trutta fario) which occurs in several alpine Bavarian limestone rivers. Because mortality can reach 100%, PDS is a serious threat for affected fish populations. Recently, Kuehn and colleagues reported that a high throughput RNA sequencing approach identified a piscine orthoreovirus (PRV) as a causative agent of PDS. We investigated samples from PDS-affected fish obtained from two exposure experiments performed at the river Iller in 2008 and 2009. Using a RT-qPCR and a well-established next-generation RNA sequencing pipeline for pathogen detection, PRV-specific RNA was not detectable in PDS fish from 2009. In contrast, PRV RNA was readily detectable in several organs from diseased fish in 2008. However, similar virus loads were detectable in the control fish which were not exposed to Iller water and did not show any signs of the disease. Therefore, we conclude that PRV is not the causative agent of PDS of brown trout in the rhithral region of alpine Bavarian limestone rivers. The abovementioned study by Kuehn used only samples from the exposure experiment from 2008 and detected a subclinical PRV bystander infection. Work is ongoing to identify the causative agent of PDS.


Asunto(s)
Enfermedades de los Peces/virología , Orthoreovirus/patogenicidad , Trucha/virología , Animales , Alemania , Secuenciación de Nucleótidos de Alto Rendimiento , Hígado/virología , Orthoreovirus/genética , ARN Viral/genética , Reacción en Cadena en Tiempo Real de la Polimerasa , Infecciones por Reoviridae , Ríos/virología , Bazo/virología
7.
Viruses ; 10(9)2018 08 24.
Artículo en Inglés | MEDLINE | ID: mdl-30149505

RESUMEN

The Modified Vaccinia virus Ankara (MVA) is a highly attenuated vaccinia virus serving as a promising vector vaccine platform to develop vaccines against infectious diseases. In contrast to the well-established replication deficiency and safety of MVA in mammals, much less is known about MVA infection in avian hosts. Here, we used a recombinant MVA expressing fluorescent reporter proteins under transcriptional control of specific viral early and late promoters to study in vivo tropism, distribution, and pathogenesis of MVA infections in embryonated chicken eggs. The chorioallantoic membrane (CAM) of embryonated chicken eggs was inoculated with recombinant MVA, MVA or phosphate-buffered saline. The infection was analyzed by fluorescence microscopy, histology, immunohistochemistry, and virus titration of embryonic tissues. After infection of the CAM, MVA spread to internal and external embryonic tissues with the liver as a major target organ. Macrophages and hematopoietic cells were identified as primary target cells of MVA infection and may be involved in virus spread. Increasing doses of MVA did not result in increased lesion severity or embryonic death. Despite MVA generalization to embryonic tissues, the CAM seems to be the major site of MVA replication. The absence of considerable organ lesions and MVA-associated mortality highlights an excellent safety profile of MVA in chicken hosts.


Asunto(s)
Pollos/virología , Enfermedades de las Aves de Corral/virología , Virus Vaccinia/patogenicidad , Tropismo Viral , Animales , Anticuerpos Monoclonales/inmunología , Embrión de Pollo , Pollos/inmunología , ADN Viral/genética , Genes Sintéticos/genética , Proteínas Fluorescentes Verdes/genética , Humanos , Hígado/inmunología , Hígado/virología , Macrófagos/inmunología , Macrófagos/virología , Enfermedades de las Aves de Corral/sangre , Enfermedades de las Aves de Corral/patología , Virus Vaccinia/genética , Virus Vaccinia/fisiología , Carga Viral , Vacunas Virales/genética , Vacunas Virales/inmunología , Virosis/sangre , Virosis/patología , Virosis/veterinaria
8.
Biologicals ; 54: 58-62, 2018 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-29759890

RESUMEN

Modified Vaccinia Virus Ankara (MVA) is a highly attenuated and replication-deficient virus serving as vaccine against infectious diseases. Here, we assessed the in vivo distribution of a recombinant MVA candidate vaccine against the Middle Eastern Respiratory Syndrome (MVA-MERS-S) in mice. Intramuscularly inoculated mice were necropsied at different time points and examined by histology, immunohistochemistry and real-time PCR. We detected inflammation and myonecrosis at the parenteral site and hyperplasia of the draining lymph nodes. MVA-MERS-S did not result in detectable lesions in tissues peripheral to the parenteral site and draining lymph nodes. Real-time PCR analysis of >240 tissue samples detected MVA-DNA predominantly at the injection site and in the draining lymph nodes, and suggested continuous clearance of the candidate vaccine during the observation period. Levels of parenteral site inflammation and hyperplasia of draining lymph nodes were considered in line with immunological responses to vaccine inoculation.


Asunto(s)
Infecciones por Coronavirus , Coronavirus del Síndrome Respiratorio de Oriente Medio/inmunología , Vacunación , Virus Vaccinia/inmunología , Vacunas Virales , Animales , Infecciones por Coronavirus/inmunología , Infecciones por Coronavirus/prevención & control , Inyecciones Intramusculares , Ratones , Vacunas Virales/inmunología , Vacunas Virales/farmacología
9.
J Gen Virol ; 98(8): 2113-2117, 2017 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-28758619

RESUMEN

We identified a novel papillomavirus, Sus scrofa papillomavirus 2 (SsPV2), which is the first papillomavirus associated with papillomas in pigs. In skin alterations of a German wild boar, showing typical gross and histological appearance of papillomas, papillomavirus-like particles were demonstrated by electron microscopy. Degenerate papillomavirus-specific primers were used to amplify and sequence parts of the viral DNA. Subsequently, the complete genomic DNA was cloned and sequenced. The SsPV2 genome had a length of 8218 bp, encoded the early proteins E6, E7, E1 and E2, the late proteins L1 and L2 and contained an upstream regulatory region. Genomic characterization demonstrated papillomavirus-typical characteristics as well as unique features. For example, the E2 protein was significantly larger than in every other known papillomavirus species. Phylogenetic analysis was not able to relate SsPV2 unambiguously with other papillomavirus species or existing genera. Therefore, it might be representative of a new papillomavirus genus.


Asunto(s)
Papillomaviridae/aislamiento & purificación , Infecciones por Papillomavirus/veterinaria , Sus scrofa/virología , Enfermedades de los Porcinos/virología , Animales , Genoma Viral , Sistemas de Lectura Abierta , Papillomaviridae/clasificación , Papillomaviridae/genética , Infecciones por Papillomavirus/virología , Porcinos , Proteínas Virales/genética , Proteínas Virales/metabolismo
10.
Genet Sel Evol ; 48: 25, 2016 Mar 31.
Artículo en Inglés | MEDLINE | ID: mdl-27036302

RESUMEN

BACKGROUND: Low birth weight and postnatal growth restriction are the most evident symptoms of dwarfism. Accompanying skeletal aberrations may compromise the general condition and locomotion of affected individuals. Several paternal half-sibs with a low birth weight and a small size were born in 2013 in the Fleckvieh cattle population. RESULTS: Affected calves were strikingly underweight at birth in spite of a normal gestation length and had craniofacial abnormalities such as elongated narrow heads and brachygnathia inferior. In spite of a normal general condition, their growth remained restricted during rearing. We genotyped 27 affected and 10,454 unaffected animals at 44,672 single nucleotide polymorphisms and performed association tests followed by homozygosity mapping, which allowed us to map the locus responsible for growth failure to a 1.85-Mb segment on bovine chromosome 3. Analysis of whole-genome re-sequencing data from one affected and 289 unaffected animals revealed a 1-bp deletion (g.15079217delC, rs723240647) in the coding region of the GON4L gene that segregated with the dwarfism-associated haplotype. We showed that the deletion induces intron retention and premature termination of translation, which can lead to a severely truncated protein that lacks domains that are likely essential to normal protein function. The widespread use of an undetected carrier bull for artificial insemination has resulted in a tenfold increase in the frequency of the deleterious allele in the female population. CONCLUSIONS: A frameshift mutation in GON4L is associated with autosomal recessive proportionate dwarfism in Fleckvieh cattle. The mutation has segregated in the population for more than 50 years without being recognized as a genetic disorder. However, the widespread use of an undetected carrier bull for artificial insemination caused a sudden accumulation of homozygous calves with dwarfism. Our findings provide the basis for genome-based mating strategies to avoid the inadvertent mating of carrier animals and thereby prevent the birth of homozygous calves with impaired growth.


Asunto(s)
Enfermedades de los Bovinos/genética , Enanismo/veterinaria , Mutación del Sistema de Lectura/genética , Genes Recesivos , Factores de Transcripción/genética , Alelos , Animales , Bovinos , Enanismo/genética , Femenino , Genotipo , Haplotipos/genética , Homocigoto , Masculino , Fenotipo , Polimorfismo de Nucleótido Simple
11.
J Am Heart Assoc ; 5(5)2016 04 27.
Artículo en Inglés | MEDLINE | ID: mdl-27121849

RESUMEN

BACKGROUND: Cell damage, tissue and vascular injury are associated with the exposure and release of intracellular components such as RNA, which promote inflammatory reactions and thrombosis. Based on the counteracting anti-inflammatory and cardioprotective functions of ribonuclease A (RNase A) in this context, its role in an experimental model of heart transplantation in rats was studied. METHODS AND RESULTS: Inbred BN/OrlRj rat cardiac allografts were heterotopically transplanted into inbred LEW/OrlRj rats. Recipients were intravenously treated every other day with saline or bovine pancreatic RNase A (50 µg/kg). Toxic side effects were not found (macroscopically and histologically). Heart tissue flow cytometry and quantitative morphological analyses of explanted hearts at postoperative day 1 or postoperative day 4 showed reduced leukocyte infiltration, edema, and thrombus formation in RNase A-treated rats. In allogeneic mixed lymphocyte reactions, RNase A decreased the proliferation of effector T cells. RNase A treatment of rats resulted in prolonged median graft survival up to 10.5 days (interquartile range 1.8) compared to 6.5 days (interquartile range 1.0) in saline treatment (P=0.001). Treatment of rats with a new generated (recombinant) human pancreatic RNase 1 prolonged median graft survival similarly, unlike treatment with (recombinant) inactive human RNase 1 (each 50 µg/kg IV every other day, 11.0 days, interquartile range 0.3, versus 8.0 days, interquartile range 0.5, P=0.007). CONCLUSIONS: Upon heart transplantation, RNase administration appears to present a promising and safe drug to counteract ischemia/reperfusion injury and graft rejection. Furthermore, RNase treatment may be considered in situations of critical reperfusion after percutaneous coronary interventions or in cardiac surgery using the heart-lung machine.


Asunto(s)
Supervivencia de Injerto/efectos de los fármacos , Trasplante de Corazón , Corazón/efectos de los fármacos , Daño por Reperfusión Miocárdica/inmunología , Miocardio/patología , Ribonucleasa Pancreática/farmacología , Animales , Bovinos , Proliferación Celular/efectos de los fármacos , Edema/inmunología , Edema/patología , Humanos , Masculino , Daño por Reperfusión Miocárdica/patología , Ratas , Ratas Endogámicas BN , Ratas Endogámicas Lew , Linfocitos T/efectos de los fármacos , Trombosis/inmunología , Trombosis/patología , Trasplante Homólogo
12.
Exp Parasitol ; 163: 46-56, 2016 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-26836446

RESUMEN

Toxoplasma gondii infects animals habiting terrestrial and aquatic environments. Its oocysts and tissue cysts are important for the horizontal transmission of this parasite. The oocyst and tissue cyst walls are crucial for the ability of the parasite to persist in the environment or in animal tissues, respectively. However, the composition of these walls is not well understood. We report the generation of monoclonal antibodies directed against wall components using mice immunized with oocyst antigens of T. gondii. One monoclonal antibody (mAb) G1/19 reacted solely with T. gondii sporozoites. The respective antigen had a relative molecular weight (Mr) of 30 kDa. MAb G1/19 failed to react with sporozoites of any other coccidian parasite species tested (Hammondia hammondi, Hammondia heydorni, Cystoisospora felis, Eimeria bovis, Sarcocystis sp.). Another mAb, designated K8/15-15, recognized antigens in sporocyst walls of the parasite and in the walls of in vivo or in vitro produced tissue cysts, as demonstrated by immunofluorescence and immunoblot assays. Antigens of 80 to a high molecular weight protein of about 350 kDa Mr were recognized by this antibody using antigen extracts from sporocysts, and from in vitro or in vivo generated tissue cysts of the parasite. Tissue cyst and sporocyst walls of H. hammondi and H. heydorni, and tissue cysts of Neospora caninum were also recognized by mAb K8/15-15. Sporocyst walls of C. felis also reacted to this mAb. The cyst walls of Sarcocystis sp. and Besnoitia besnoiti were not recognized by mAb K8/15-15. Reactivity by a single mAb against T. gondii antigens in tissue cysts and sporocysts had not been reported previously. MAb K8/15-15 may be a practical tool for the identification of both cysts and sporocysts of the parasite, and may also be potentially employed in proteomic studies on the identification of new components of the cyst and sporocyst walls of T. gondii.


Asunto(s)
Anticuerpos Monoclonales/inmunología , Antígenos de Protozoos/inmunología , Inmunoglobulina G/inmunología , Toxoplasma/inmunología , Animales , Anticuerpos Monoclonales/biosíntesis , Antígenos de Protozoos/administración & dosificación , Gatos , Bovinos , Coccidios/clasificación , Coccidios/inmunología , Perros , Técnica del Anticuerpo Fluorescente , Hibridomas , Inmunización Secundaria , Inyecciones Intravenosas , Inyecciones Subcutáneas , Ratones , Ratones Endogámicos BALB C , Ratones Endogámicos C57BL , Oocistos/inmunología , Ovinos
13.
J Gen Virol ; 97(1): 128-133, 2016 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-26555294

RESUMEN

We describe a novel papillomavirus - Rusa alfredi papillomavirus 1 (RalPV1) - which causes endemic fibropapillomatosis in the European conservation breeding population of the highly endangered Visayan spotted deer (Rusa alfredi). Degenerated papillomavirus-specific primers were used to amplify and sequence parts of the viral DNA. Subsequently, the complete genomic DNA was cloned and the sequence was determined. The RalPV1 genome has a length of 8029 bp, encodes the early proteins E6, E7, E1, E2 and E5, the two late proteins L1 and L2 and contains an upstream regulatory region. Highest sequence identities were observed with two deltapapillomaviruses, the Capreolus capreolus PV1 and Cervus elaphus PV1. Pairwise comparisons and phylogenetic analysis based on the ORF L1 suggested that RalPV1 is a putative new type of the papillomavirus species Deltapapillomavirus 5.


Asunto(s)
Ciervos/virología , Deltapapillomavirus/clasificación , Deltapapillomavirus/aislamiento & purificación , Enfermedades Endémicas , Papiloma/veterinaria , Animales , Análisis por Conglomerados , ADN Viral/química , ADN Viral/genética , Europa (Continente)/epidemiología , Genoma Viral , Histocitoquímica , Microscopía , Datos de Secuencia Molecular , Papiloma/epidemiología , Papiloma/patología , Papiloma/virología , Filogenia , Análisis de Secuencia de ADN , Homología de Secuencia , Proteínas Virales/genética
14.
Berl Munch Tierarztl Wochenschr ; 128(11-12): 464-72, 2015.
Artículo en Alemán | MEDLINE | ID: mdl-26697713

RESUMEN

Poxviruses as expression vectors are widely used in medical research for the development of recombinant vaccines and molecular therapies. Here we review recent accomplishments in vaccine research using recombinant modified vaccinia virus ankara (MVA). MVA is a highly attenuated vaccinia virus strain that originated from serial tissue culture passage in chicken embryo fibroblasts more than 40 years ago. Growth adaptation to avian host cells caused deletions and mutations in the viral genome affecting about 15% of the original genetic information. In consequence, MVA is replication-deficient in cells of mammalian origin and fails to produce many of the virulence factors encoded by conventional vaccinia virus. Because of its safety for the general environment MVA can be handled under conditions of biosafety level one. Non-replicating MVA can enter any target cell and activate its molecular life cycle to express all classes of viral and recombinant genes. Therefore, recombinant MVA have been established as an extremely safe and efficient vector system for vaccine development in medical research. By now, various recombinant MVA vaccines have been found safe and immunogenic when used for phase I/II clinical testing in humans, and suitable for industrial scale production following good practice of manufacturing. Thus, there is an obvious usefulness of recombinant MVA vaccines for novel prophylactic and therapeutic approaches also in veterinary medicine. Results from first studies in companion and farm animals are highly promising.


Asunto(s)
Animales Domésticos , Vectores Genéticos , Virus Vaccinia/inmunología , Medicina Veterinaria/métodos , Vacunas Virales , Animales , Regulación Viral de la Expresión Génica , Vacunas Atenuadas/genética , Vacunas Atenuadas/inmunología , Vacunas Sintéticas/administración & dosificación , Vacunas Sintéticas/normas , Virus Vaccinia/genética , Vacunas Virales/genética , Vacunas Virales/inmunología
15.
Xenotransplantation ; 22(6): 427-42, 2015.
Artículo en Inglés | MEDLINE | ID: mdl-26602740

RESUMEN

BACKGROUND: As a step towards clinical cardiac xenotransplantation, our experimental heterotopic intrathoracic xenotransplantation model offers a beating and ejecting donor heart while retaining the recipient's native organ as a backup in case of graft failure. Clinically applicable immunosuppressive regimens (IS) were investigated first, then treatments known to be effective in hypersensitized patients or those with recalcitrant rejection reactions. METHODS: Consecutive experiments were carried out between 2009 and 2013. Twenty-one genetically modified pigs (GGTA1-knockout/hCD46/± thrombomodulin, in one case HLA-E instead) were used as donors. In all experiments, two cycles of immunoabsorption reduced preformed antibodies. Recipient baboons were divided into two groups according to IS regimen: In group one (n = 10), pre-treatment started either one (anti-CD20) or four weeks (anti-CD20 plus the proteasome inhibitor bortezomib) prior to transplantation. The extended conventional (as for allotransplantation) immunosuppressive maintenance regimen included anti-thymocyte globuline, tacrolimus, mycophenolate mofetil, methylprednisolone and weekly anti-CD20. In group two (n = 11), myeloablative pre-treatment as in multiple myeloma patients (long and short regimens) was added to extended conventional IS; postoperative total thoracic and abdominal lymphoid irradiation (TLI; single dose of 600 cGY) was used to further reduce antibody-producing cells. RESULTS: In the perioperative course, the surgical technique was safely applied: 19 baboons were weaned off extracorporeal circulation and 17 extubated. Nine animals were lost in the early postoperative course due to causes unrelated to surgical technique or IS regimen. Excluding these early failures, median graft survival times of group 1 and 2 were 18.5 (12-50) days and 16 (7-35) days. Necropsy examination of group 1 donor organs revealed hypertrophy of the left ventricular wall in the six longer-lasting grafts; myocardial histology confirmed pre-clinical suspicion of humoral rejection, which was not inhibited by the extended conventional IS including intensified treatments, and signs of thrombotic microangiopathy. Grafts of group 2 presented with only mild-to-moderate features of humoral rejection and thrombotic microangiopathy, except in one case of delayed rejection on day 17. The other experiments in this group were terminated because of untreatable pulmonary oedema, recurring ventricular fibrillation, Aspergillus sepsis, as well as a combination of a large donor organ and late toxic side effects due to TLI. CONCLUSIONS: Longer-term results were difficult to achieve in this model due to the IS regimens used. However, we conclude that heterotopic intrathoracic heart transplantation may be an option for clinical xenotransplantation.


Asunto(s)
Rechazo de Injerto/inmunología , Supervivencia de Injerto/inmunología , Trasplante de Corazón , Inmunosupresores/farmacología , Animales , Animales Modificados Genéticamente , Anticuerpos/inmunología , Anticuerpos/farmacología , Trasplante de Corazón/métodos , Porcinos , Trasplante Heterólogo/métodos
16.
BMC Vet Res ; 11: 35, 2015 Feb 14.
Artículo en Inglés | MEDLINE | ID: mdl-25886463

RESUMEN

BACKGROUND: Bovine besnoitiosis is an emerging protozoan disease in cattle. Neither vaccines nor chemotherapeutic drugs are currently available for prevention and treatment of Besnoitia besnoiti infections. Therefore the implementation of appropriate disease management strategies is of utmost importance. The aim of this longitudinal study was to complement current knowledge on the chronology of disease progression. This was realized by correlating clinical findings in early stages of naturally acquired bovine besnoitiosis with results of real-time PCR of skin biopsies and of two western immunoblots and an immunofluorescent antibody test (IFAT). Animals for this study were obtained by i) closely monitoring a cow-calf operation with a high prevalence of bovine besnoitiosis for cases of acute disease, and by ii) conducting a 12-week cohabitation experiment on pasture with five healthy heifers, a healthy bull and five B. besnoiti infected cows. A control group of six healthy heifers was kept at a minimal distance of 20 m. Further, the spectrum of potential insect vectors was determined. RESULTS: Infected cattle were followed up to a maximum of 221 days after first detection of B. besnoiti antibodies. Two severely affected cows developed visible and palpable alterations of skin, a decrease in body condition despite good feed intake, and chronic bovine besnoitiosis-associated laminitis leading to non-healing sole ulcers. The cows also had high reciprocal IFAT titers and high loads of parasite DNA in skin samples. Two heifers developed a mild clinical course characterized by few parasitic cysts visible in the scleral conjunctivae and vestibula vaginae. Both heifers became infected during the time of high insect activity of the species Musca domestica, Musca autumnalis, Haematobia irritans, and Stomoxys calcitrans. When a third heifer became subclinically infected, low insect activity was recorded. None of the six control heifers contracted a B. besnoiti infection. CONCLUSIONS: In chronic besnoitiosis, the severe clinical course apparently corresponded with high reciprocal IFAT titers and high loads of parasite DNA in skin, whereas mild and subclinical cases displayed lower values. Bovine besnoitiosis-associated laminitis represents an important complication in severe chronic disease which severely impairs animal welfare.


Asunto(s)
Enfermedades de los Bovinos/parasitología , Coccidiosis/veterinaria , Sarcocystidae , Animales , Anticuerpos Antiprotozoarios/inmunología , Western Blotting , Bovinos , Enfermedades de los Bovinos/patología , Coccidiosis/patología , Dípteros , Progresión de la Enfermedad , Femenino , Técnica del Anticuerpo Fluorescente/veterinaria , Microscopía/veterinaria , Reacción en Cadena en Tiempo Real de la Polimerasa/veterinaria , Piel/patología , Factores de Tiempo
17.
BMC Vet Res ; 11: 32, 2015 Feb 13.
Artículo en Inglés | MEDLINE | ID: mdl-25880447

RESUMEN

BACKGROUND: The emerging disease bovine besnoitiosis is caused by the apicomplexan parasite Besnoitia besnoiti. Clinical signs of acute besnoitiosis are pyrexia, anorexia and subcutaneous edema. In subacute and chronic besnoitiosis parasitic cysts arise in a variety of tissues and affected cattle display skin lesions and weight loss. In all stages of bovine besnoitiosis, lesions can be found in many organ systems and therefore presumably alter a variety of laboratory parameters. In this study, the impact of naturally acquired acute, subacute and chronic bovine besnoitiosis on hematologic parameters, serum chemistry, and enzyme activities was investigated. Laboratory parameters of two Simmental heifers and two Limousin cows were monitored during acute, subacute and chronic besnoitiosis and in another Simmental heifer during subclinical besnoitiosis. To determine aberrations of laboratory parameters, values were compared with reference ranges obtained from B. besnoiti negative Simmentals (224 samples of nine animals) and Limousins (41 animals). Further, laboratory parameters of B. besnoiti seropositive Limousin cows (54 animals; 32 of these showing clinical signs) and healthy B. besnoiti seronegative Limousin cows (41 animals) were compared. RESULTS: During acute and subacute besnoitiosis, a reduction of leukocyte and erythrocyte concentrations, hematocrit, serum albumin, urea, magnesium, and calcium concentrations were observed. Serum total protein, globulin, total bilirubin and creatinine concentrations were increased and aspartate transaminase (AST) and creatine kinase (CK) activities were elevated. In chronic besnoitiosis, erythrocyte parameters were statistically significantly lower, and total protein and globulin concentrations were significantly higher in B. besnoiti seropositive compared with B. besnoiti seronegative Limousin cows. CONCLUSIONS: In this study, altered laboratory parameters during the course of naturally acquired acute, subacute and chronic bovine besnoitiosis are described for the first time. Only a few animals were examined in acute and subacute besnoitiosis, however the alterations of laboratory parameters during these stages reflected i) the acute inflammatory state (e.g. high levels of serum globulin fractions), ii) clinical findings such as disturbed condition (e.g. bilirubin concentrations), and iii) lesions such as muscle necroses described in the literature (e.g. AST or CK activities). Chronic besnoitiosis led to typical alterations of chronic inflammatory diseases like hyper-(gamma)-globulinemia or reduced erythrocyte concentrations.


Asunto(s)
Enfermedades de los Bovinos/parasitología , Coccidiosis/veterinaria , Sarcocystidae , Animales , Bilirrubina/sangre , Bovinos/sangre , Bovinos/parasitología , Enfermedades de los Bovinos/sangre , Coccidiosis/sangre , Progresión de la Enfermedad , Electroforesis en Gel de Agar/veterinaria , Femenino , Globulinas/análisis , Hematócrito/veterinaria , Hemoglobinas/análisis , Recuento de Leucocitos , Albúmina Sérica/análisis
18.
BMC Genomics ; 15: 623, 2014 Jul 22.
Artículo en Inglés | MEDLINE | ID: mdl-25052073

RESUMEN

BACKGROUND: Bovine hereditary zinc deficiency (BHZD) is an autosomal recessive disorder of cattle, first described in Holstein-Friesian animals. Affected calves suffer from severe skin lesions and show a poor general health status. Recently, eight calves with the phenotypic appearance of BHZD have been reported in the Fleckvieh cattle population. RESULTS: In spite of the similar disease phenotypes, SLC39A4, the gene responsible for BHZD in Holstein-Friesian was excluded as underlying gene for the disorder in the affected Fleckvieh calves. In order to identify the disease-associated region, genotypes of eight affected calves obtained with the Illumina BovineHD BeadChip comprising 777,962 SNPs were contrasted with the genotypes of 1,339 unaffected animals. A strong association signal was observed on chromosome 21 (P = 5.87 × 10(-89)). Autozygosity mapping in the eight affected animals revealed a common segment of extended homozygosity encompassing 1,023 kb (BTA 21: 70,550,045 - 71,573,501). This region contains 17 genes/transcripts, among them two genes encoding gastro-intestinal zinc transporters (CRIP1, CRIP2). However, no mutation that was compatible with recessive inheritance could be detected in these candidate genes. One of the affected calves was re-sequenced together with 42 unaffected Fleckvieh animals. Analysis of the sequencing data revealed a nonsense mutation (p.W215X) in a phospholipase encoding gene (PLD4) as candidate causal polymorphism. To confirm the causality, genotypes of the p.W215X-mutation were obtained from 3,650 animals representing three different breeds. None of the unaffected animals was homozygous for the defect allele, while all eight affected calves were homozygous. The deleterious effect of the mutation is manifested in a significantly lower survival rate of descendants from risk matings when compared with the survival rate of descendants from non-risk matings. The deleterious allele has an estimated frequency of 1.1% in the Fleckvieh population. CONCLUSION: Our results provide strong evidence that a newly identified recessive disorder in the Fleckvieh population is caused by a nonsense mutation in PLD4, most likely resulting in an impaired function of the encoded protein. Although the phenotype of affected calves strongly resembles BHZD, a zinc deficiency resulting from malabsorption is unlikely to be responsible for the diseased Fleckvieh calves.


Asunto(s)
Enfermedades de los Bovinos/genética , Errores Innatos del Metabolismo de los Metales/genética , Fosfolipasa D/genética , Animales , Bovinos , Enfermedades de los Bovinos/patología , Mapeo Cromosómico , Codón sin Sentido , Dermis/patología , Genotipo , Secuenciación de Nucleótidos de Alto Rendimiento , Homocigoto , Proteínas con Dominio LIM/genética , Errores Innatos del Metabolismo de los Metales/patología , Fenotipo , Polimorfismo de Nucleótido Simple , Análisis de Secuencia de ADN , Síndrome , Zinc/metabolismo
19.
J Virol ; 88(18): 10946-57, 2014 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-25008931

RESUMEN

UNLABELLED: Immunization with modified vaccinia virus Ankara (MVA) can rapidly protect mice against lethal ectromelia virus (ECTV) infection, serving as an experimental model for severe systemic infections. Importantly, this early protective capacity of MVA vaccination completely depends on virus-specific cytotoxic CD8(+) T cell responses. We used MVA vaccination in the mousepox challenge model using ECTV infection to investigate the previously unknown factors required to elicit rapid protective T cell immunity in normal C57BL/6 mice and in mice lacking the interferon alpha/beta receptor (IFNAR(-/-)). We found a minimal dose of 10(5) PFU of MVA vaccine fully sufficient to allow robust protection against lethal mousepox, as assessed by the absence of disease symptoms and failure to detect ECTV in organs from vaccinated animals. Moreover, MVA immunization at low dosage also protected IFNAR(-/-) mice, indicating efficient activation of cellular immunity even in the absence of type I interferon signaling. When monitoring for virus-specific CD8(+) T cell responses in mice vaccinated with the minimal protective dose of MVA, we found significantly enhanced levels of antigen-specific T cells in animals that were MVA vaccinated and ECTV challenged compared to mice that were only vaccinated. The initial priming of naive CD8(+) T cells by MVA immunization appears to be highly efficient and, even at low doses, mediates a rapid in vivo burst of pathogen-specific T cells upon challenge. Our findings define striking requirements for protective emergency immunization against severe systemic infections with orthopoxviruses. IMPORTANCE: We demonstrate that single-shot low-dose immunizations with vaccinia virus MVA can rapidly induce T cell-mediated protective immunity against lethal orthopoxvirus infections. Our data provide new evidence for an efficient protective capacity of vaccination with replication-deficient MVA. These data are of important practical relevance for public health, as the effectiveness of a safety-tested, next-generation smallpox vaccine based on MVA is still debated. Furthermore, producing sufficient amounts of vaccine is expected to be a major challenge should an outbreak occur. Moreover, prevention of other infections may require rapidly protective immunization; hence, MVA could be an extremely useful vaccine for delivering heterologous T cell antigens, particularly for infectious diseases that fit a scenario of emergency vaccination.


Asunto(s)
Linfocitos T CD8-positivos/inmunología , Protección Cruzada , Virus de la Ectromelia/fisiología , Ectromelia Infecciosa/inmunología , Receptor de Interferón alfa y beta/deficiencia , Virus Vaccinia/inmunología , Animales , Linfocitos T CD8-positivos/virología , Virus de la Ectromelia/inmunología , Ectromelia Infecciosa/virología , Femenino , Inmunidad Celular , Inmunización , Ratones , Ratones Endogámicos C57BL , Ratones Noqueados , Receptor de Interferón alfa y beta/genética , Receptor de Interferón alfa y beta/inmunología , Vaccinia/inmunología , Vaccinia/virología , Virus Vaccinia/genética
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