Publications by authors named "Ciriaco Ligios"

29 Publications

  • Page 1 of 1

"Frozen evolution" of an RNA virus suggests accidental release as a potential cause of arbovirus re-emergence.

PLoS Biol 2020 04 28;18(4):e3000673. Epub 2020 Apr 28.

MRC-University of Glasgow Centre for Virus Research, Glasgow, United Kingdom.

The mechanisms underlying virus emergence are rarely well understood, making the appearance of outbreaks largely unpredictable. Bluetongue virus serotype 8 (BTV-8), an arthropod-borne virus of ruminants, emerged in livestock in northern Europe in 2006, spreading to most European countries by 2009 and causing losses of billions of euros. Although the outbreak was successfully controlled through vaccination by early 2010, puzzlingly, a closely related BTV-8 strain re-emerged in France in 2015, triggering a second outbreak that is still ongoing. The origin of this virus and the mechanisms underlying its re-emergence are unknown. Here, we performed phylogenetic analyses of 164 whole BTV-8 genomes sampled throughout the two outbreaks. We demonstrate consistent clock-like virus evolution during both epizootics but found negligible evolutionary change between them. We estimate that the ancestor of the second outbreak dates from the height of the first outbreak in 2008. This implies that the virus had not been replicating for multiple years prior to its re-emergence in 2015. Given the absence of any known natural mechanism that could explain BTV-8 persistence over this long period without replication, we hypothesise that the second outbreak could have been initiated by accidental exposure of livestock to frozen material contaminated with virus from approximately 2008. Our work highlights new targets for pathogen surveillance programmes in livestock and illustrates the power of genomic epidemiology to identify pathways of infectious disease emergence.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1371/journal.pbio.3000673DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7188197PMC
April 2020

Dicrocoeliosis in extensive sheep farms: a survey.

Parasit Vectors 2019 Jul 12;12(1):342. Epub 2019 Jul 12.

Istituto Zooprofilattico Sperimentale della Sardegna G. Pegreffi, Via Duca degli Abruzzi 8, Sassari, Sardinia, Italy.

Background: This study investigated the epidemiological and molecular aspects of dicrocoeliosis in extensive sheep farms.

Methods: From 2013 to 2014, copromicroscopical analyses in 190 dairy sheep farms and anatomo-pathological inspections in six slaughterhouses were carried in Sardinia, Italy. Rectal faecal samples were analyzed using the FLOTAC® method, and anatomo-pathological examinations were based on detecting thickened terminal bile ducts (TTBDs). In addition, genetic analyses were conducted on representative DNA samples of adult Dicrocoelium spp.

Results: Ninety-seven (51.1%) out of 190 sheep farms were coprologically positive for Dicrocoelium spp. In the liver, on the surface and cut surface, TTBDs were reported in 40.1% (309/770) and 15.3% (118/770) of the animals examined, respectively, with an overall prevalence of 25.5% (196/770). No intraspecific genetic variation was observed among the Dicrocoelium dendriticum isolates.

Conclusions: Our survey reveals the widespread presence of D. dendriticum in Sardinia, although seasonal, geographical and climatic conditions might be key factors in modulating the infection prevalence. Examining typical lesions due to D. dendriticum in the liver in abattoirs can be used as a marker for tracking chronic dicrocoeliosis infection.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1186/s13071-019-3609-2DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6625022PMC
July 2019

Persistence of Bluetongue virus serotype 1 virulence in sheep blood refrigerated for 10 years.

Vet Ital 2018 12 31;54(4):349-353. Epub 2018 Dec 31.

Istituto Zooprofilattico Sperimentale della Sardegna, Sassari, Italy.

This paper reports that Bluetongue virus serotype 1 (BTV-1) infected blood collected during the 2006 Sardinia (Italy) epidemic from a ewe with clinical disease and stored at ~ 5°C for 10 years, caused Bluetongue (BT)-like clinical disease and death when inoculated into a susceptible Sarda breed ram. Anatomo-histopathological examination and Real-Time Reverse Transcriptase PCR (Real-Time RT-PCR) confirmed the presence of BTV-1 in several tissues proving that the BTV-1 2006 isolate has maintained its infectivity and virulence.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.12834/VetIt.1344.7401.3DOI Listing
December 2018

Testicular Degeneration and Infertility following Arbovirus Infection.

J Virol 2018 10 12;92(19). Epub 2018 Sep 12.

Istituto Zooprofilattico Sperimentale della Sardegna, Sassari, Italy

Arboviruses can cause a variety of clinical signs, including febrile illness, arthritis, encephalitis, and hemorrhagic fever. The recent Zika epidemic highlighted the possibility that arboviruses may also negatively affect the male reproductive tract. In this study, we focused on bluetongue virus (BTV), the causative agent of bluetongue and one of the major arboviruses of ruminants. We show that rams that recovered from bluetongue displayed signs of testicular degeneration and azoospermia up to 100 days after the initial infection. Importantly, testicular degeneration was induced in rams experimentally infected with either a high (BTV-1)- or a low (BTV-1)-virulence strain of BTV. Rams infected with the low-virulence BTV strain displayed testicular lesions in the absence of other major clinical signs. Testicular lesions in BTV-infected rams were due to viral replication in the endothelial cells of the peritubular areas of the testes, resulting in stimulation of a type I interferon response, reduction of testosterone biosynthesis by Leydig cells and destruction of Sertoli cells and the blood-testis barrier in more severe cases. Hence, BTV induces testicular degeneration and disruption of spermatogenesis by replicating solely in the endothelial cells of the peritubular areas unlike other gonadotropic viruses. This study shows that a naturally occurring arboviral disease can cause testicular degeneration and affect male fertility at least temporarily. During the recent Zika epidemic, it has become apparent that arboviruses could potentially cause reproductive health problems in male patients. Little is known regarding the effects that arboviruses have on the male reproductive tract. Here, we studied bluetongue virus (BTV), an arbovirus of ruminants, and its effects on the testes of rams. We show that BTV was able to induce testicular degeneration in naturally and experimentally infected rams. Testicular degeneration was caused by BTV replication in the endothelial cells of the peritubular area surrounding the seminiferous tubules (the functional unit of the testes) and was associated with a localized type I interferon response, destruction of the cells supporting the developing germinal cells (Sertoli cells), and reduction of testosterone synthesis. As a result of BTV infection, rams became azoospermic. This study highlights that problems in the male reproductive tract caused by arboviruses could be more common than previously thought.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1128/JVI.01131-18DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6146814PMC
October 2018

Atypical outbreak of acute coenurosis by Taenia multiceps in a sheep flock.

Parasitol Res 2018 Jun 18;117(6):1985-1988. Epub 2018 Apr 18.

Laboratorio di Parassitologia, Ospedale Didattico Veterinario, Dipartimento di Medicina Veterinaria, Università degli Studi di Sassari, Sassari, Italy.

Herein, we examined the brain of adult ewes and lambs less than 30 days old which were found affected by neurological signs in a flock located in Sardinia (Italy). Gross anatomo-pathological examination of all brains of the animals revealed multiple linear reddish-yellow foci of necrotic purulent inflammation due to oncosphere migration. Histologically, we confirmed a multifocal pyo-granulomatous meningo-encephalitis both in ewes and in lambs, confirming acute coenurosis. Morphological examination and DNA sequencing identified the Taenia multiceps we isolated as Tm1 strain. This report describes for the first time a natural acute coenurosis infection in suckling lambs under 30 days of age.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1007/s00436-018-5873-zDOI Listing
June 2018

Depletion of follicular dendritic cells in tonsils collected from PMWS-affected pigs.

Arch Virol 2017 May 28;162(5):1281-1287. Epub 2017 Jan 28.

Istituto Zooprofilattico Sperimentale della Sardegna "G. Pegreffi", Via Vienna 2, 07100, Sassari, Italy.

Post-weaning multisystemic wasting syndrome (PMWS) is a relevant, worldwide disease caused by porcine circovirus type 2 (PCV2). Microscopically, PMWS is mainly characterized by lymphocytic depletion, macrophage infiltration and syncytia in lymphoid tissues. Some data suggest that follicular dendritic cells (FDCs) could be infected by PCV2, thus likely playing a role in the pathogenesis of PMWS. The present paper aims at assessing, qualitatively and quantitatively, the FDCs' network in the soft palate tonsils of clinically healthy and PMWS-affected pigs. Consecutive tissue sections were tested by immunohistochemistry to detect PCV2, FDCs and macrophages. FDCs and PCV2 antigens were quantitatively assessed by means of the Image J software and results submitted to statistical analysis. Our data demonstrated that FDCs are significantly reduced in PMWS-affected pigs compared with healthy pigs and that FDCs' depletion should be considered among microscopic features of PMWS. It is reasonable to hypothesize that depletion of FDCs further compromises the immune response and enhances the occurrence and the severity of secondary infections, which are relevant for the clinical manifestation of PMWS.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1007/s00705-017-3244-1DOI Listing
May 2017

Pathological findings in a Dachshund-cross dog with neuroaxonal dystrophy.

Acta Vet Scand 2016 Jun 7;58(1):37. Epub 2016 Jun 7.

Istituto Zooprofilattico Sperimentale della Sardegna "G.Pegreffi", Via Duca degli Abruzzi 8, 07100, Sassari, Italy.

Background: Neuroaxonal dystrophy (NAD) is a neurodegenerative condition affecting humans and animals characterized by the widespread presence of swollen axons (spheroids).

Case Presentation: Herein, we report the pathological findings in a case of neuroaxonal dystrophy in a Dachshund-cross puppy, which was euthanized because of a proprioceptive positioning deficits and irreversible ataxia of the hind limbs. Histologically, there was a bilaterally symmetric neuroaxonal dystrophy with eosinophilic axonal spheroids exclusively localized at the level of the ventral posterior lateral nucleus of the thalamus, medial lemniscus, gracilis nucleus, medial cuneatus nucleus in the brain as well as the gracilis and cuneatus fasciculi throughout the spinal cord.

Conclusion: To the authors' knowledge, this is the first report of canine neuroaxonal dystrophy with this exclusive and specific localization only in the neuronal circuit implicated in the transmission of conscious proprioceptive information.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1186/s13028-016-0218-3DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC4895804PMC
June 2016

Glioblastoma with oligodendroglioma component in a ewe.

J Vet Diagn Invest 2016 Jul 6;28(4):449-54. Epub 2016 May 6.

Istituto Zooprofilattico Sperimentale della Sardegna "G. Pegreffi", Sassari, Italy (Pintus, Masia, Maestrale, Cancedda, Contu, Macciocu, Ligios)Facoltà di Medicina Veterinaria, Università degli Studi di Teramo, Teramo, Italy (Marruchella)

Herein we describe a glioblastoma partially occupying the telencephalic portion of the left cerebral hemisphere of a Sardinian (syn. Sarda) breed ewe. Microscopically, the mass consisted of a pleomorphic spindle-shaped cell component organized as bundles and numerous small areas of round cells displaying an oligodendroglioma-like aspect. A high number of mitotic figures, large areas of necrosis surrounded by pseudopalisading glial cells, and multiple foci of dystrophic mineralization were also observed. The neoplasm was highly vascularized with glomerular vascular proliferation. Immunohistochemically, neoplastic cells proved to be strongly positive for nestin, vimentin, and olig-2, whereas they were invariably negative for synaptophysin. Few neoplastic cells and reactive astrocytes, mainly located at the edge of necrotic foci, proved to be positive for glial fibrillary acidic protein, whereas glomerular vascular proliferation was clearly positive for factor VIII and vascular endothelial growth factor. Gene sequencing analysis demonstrated homozygous p53 tumor suppressor gene (TP53) point mutations in the DNA-binding domain located in exon 8. The presence of round cells immunoreactive for olig-2 demonstrated that this tumor is a glioblastoma with oligodendroglioma component. Our pathologic, immunohistochemical, and molecular findings largely overlap those previously reported in humans and dogs.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1177/1040638716644646DOI Listing
July 2016

Genetic and Pathological Follow-Up Study of Goats Experimentally and Naturally Exposed to a Sheep Scrapie Isolate.

J Virol 2015 Oct 22;89(19):10044-52. Epub 2015 Jul 22.

Istituto Zooprofilattico Sperimentale of Sardinia, Sassari, Italy

Unlabelled: Thirty-seven goats carrying different prion protein genotypes (PRNP) were orally infected with a classical scrapie brain homogenate from wild-type (ARQ/ARQ) sheep and then mated to obtain 2 additional generations of offspring, which were kept in the same environment and allowed to be naturally exposed to scrapie. Occurrence of clinical or subclinical scrapie was observed in the experimentally infected goats (F0) and in only one (F1b) of the naturally exposed offspring groups. In both groups (F0 and F1b), goats carrying the R154H, H154H, R211Q, and P168Q-P240P dimorphisms died of scrapie after a longer incubation period than wild-type, G37V, Q168Q-P240P, and S240P goats. In contrast, D145D and Q222K goats were resistant to infection. The immunobiochemical signature of the scrapie isolate and its pathological aspects observed in the sheep donors were substantially maintained over 2 goat generations, i.e., after experimental and natural transmission. This demonstrates that the prion protein gene sequence, which is shared by sheep and goats, is more powerful than any possible but unknown species-related factors in determining scrapie phenotypes. With regard to genetics, our study confirms that the K222 mutation protects goats even against ovine scrapie isolates, and for the first time, a possible association of D145 mutation with scrapie resistance is shown. In addition, it is possible that the sole diverse frequencies of these genetic variants might, at least in part, shape the prevalence of scrapie among naturally exposed progenies in affected herds.

Importance: This study was aimed at investigating the genetic and pathological features characterizing sheep-to-goat transmission of scrapie. We show that in goats with different prion protein gene mutations, the K222 genetic variant is associated with scrapie resistance after natural and experimental exposure to ovine prion infectivity. In addition, we observed for the first time a protective effect of the D145 goat variant against scrapie. Importantly, our results demonstrate that the phenotypic characteristic of the wild-type sheep scrapie isolate is substantially preserved in goats carrying different susceptible PRNP gene variants, thus indicating that the prion protein gene sequence, which is shared by sheep and goats, plays a fundamental role in determining scrapie phenotypes.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1128/JVI.01262-15DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC4577906PMC
October 2015

(1)H NMR brain metabonomics of scrapie exposed sheep.

Mol Biosyst 2015 Jul;11(7):2008-16

Department of Chemical and Geological Sciences, University of Cagliari, Monserrato, Italy.

While neurochemical metabolite modifications, determined by different techniques, have been diffusely reported in human and mice brains affected by transmissible spongiform encephalopathies (TSEs), this aspect has been little studied in the natural animal hosts with the same pathological conditions so far. Herein, we investigated, by high resolution (1)H NMR spectroscopy and multivariate statistical data analysis, the brain metabolite profile of sheep exposed to a scrapie agent in a naturally affected flock. On the basis of clinical examinations and western blotting analysis for the pathological prion protein (PrP(Sc)) in brain tissues, sheep were catalogued as not infected (H), infected with clinical signs (S), and infected without clinical signs (A). By discriminant analysis of spectral data, comparing S vs. H, we found a different metabolite distribution, with inosine, cytosine, creatine, and lactate being higher in S than in H brains, while the branched chain amino acids (leucine, isoleucine, and valine), phenylalanine, uracil, tyrosine, gamma-amino butyric acid, total aspartate (aspartate + N-acetyl aspartate) being lower in S. By a soft independent modelling of class analogy approach, 1 out of 3 A samples was assigned to class H. Furthermore, A brains were found to be higher in choline and choline-containing compounds. By means of partial least squares regression, an excellent correlation was found between the PrP(Sc) amount and the (1)H NMR metabolite profile of infected (S and A) sheep, and the metabolite mostly correlated with PrP(Sc) was alanine. The overall results, obtained using different chemometric tools, were able to describe a brain metabolite profile of infected sheep with and without clinical signs, compared to healthy ones, and indicated alanine as a biomarker for PrP(Sc) amounts in scrapie brains.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1039/c5mb00138bDOI Listing
July 2015

Genetic and pathological characteristics of Cryptococcus gattii and Cryptococcus neoformans var. neoformans from meningoencephalitis in autochthonous goats and mouflons, Sardinia, Italy.

Vet Microbiol 2015 Jun 17;177(3-4):409-13. Epub 2015 Mar 17.

Istituto Zooprofilattico Sperimentale della Sardegna, G.Pegreffi, via Duca degli Abruzzi 8, 07100 Sassari, Italy. Electronic address:

In this study, we examined in Sardinia the brain of 555 autochthonous sheep, 50 goats, and 4 mouflons which were found affected by neurological signs. We found 6 goats and one mouflon with meningoencephalitis caused by Cryptococcus sp. There was no evidence of cryptococcal infections in any of the examined sheep. MLST genotyping on Cryptococcus sp. isolates identified Cryptococcus gatti genotype AFLP4/VGI and Cryptococcus neoformans var. neoformans genotype AFLP2/VNIV. Phylogenetically, all Cryptococcus gattii isolates fell within the autochthonous animal, human and environmental Mediterranean isolate cluster, forming a distinct branch along with environmental strains from Alicante, in the southern Mediterranean coast of Spain.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1016/j.vetmic.2015.03.008DOI Listing
June 2015

Cetacean strandings in Italy: an unusual mortality event along the Tyrrhenian Sea coast in 2013.

Dis Aquat Organ 2014 Apr;109(1):81-6

IZS Piemonte Liguria Valle d'Aosta, Via Bologna, 148,10154 Torino, Italy.

An unusual mortality event involving cetaceans, mainly striped dolphins Stenella coeruleoalba (Meyen, 1833), occurred along the Tyrrhenian Sea coast of Italy during the first 3 mo of 2013. Based on post-mortem analyses carried out according to body condition on 66 dolphins (54% of stranded animals), several hypotheses to explain the causes of this mortality event were proposed. Although no definitive conclusions can be drawn, dolphin morbillivirus was deemed the most likely cause, although other infectious agents (including Photobacterium damselae damselae and herpesvirus) or environmental factors may also have contributed to this recent mortality event.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.3354/dao02726DOI Listing
April 2014

Role of palatine tonsils as a prion entry site in classical and atypical experimental sheep scrapie.

J Virol 2014 Jan 6;88(2):1065-70. Epub 2013 Nov 6.

Istituto Zooprofilattico Sperimentale of Sardinia, Sassari, Italy.

Atypical and classical scrapie-infected sheep brain tissue was monolaterally injected into the tonsils of lambs to investigate their role as a prion entry point. We first detected classical PrP(Sc) within the inoculated tonsil and in the ipsilateral retropharyngeal lymph node at 3 months postinoculation (p.i.). At 7 months p.i., PrP(Sc) colonized other lymphoid tissues bilaterally, including ileal Peyer's patches. The earliest PrP(Sc) deposition within the brain was ipsilaterally observed at 9 months p.i. in the substantia reticularis of the medulla oblongata. At 12 months p.i., PrP(Sc) deposition was present bilaterally in the nucleus parasympathicus nervi vagi, as well as in the intermediolateral cell column of the thoracolumbar spinal cord. No PrP(Sc) was detected in the lambs inoculated with atypical scrapie. These findings suggest that neuroinvasion may naturally occur from the tonsil after a widespread prion replication within the lymphoid tissues during classical scrapie only, thus mimicking the pathogenesis after oral ingestion.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1128/JVI.02750-13DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3911675PMC
January 2014

The new French 2010 Rabbit Hemorrhagic Disease Virus causes an RHD-like disease in the Sardinian Cape hare (Lepus capensis mediterraneus).

Vet Res 2013 Oct 7;44:96. Epub 2013 Oct 7.

Istituto Zooprofilattico Sperimentale della Lombardia ed Emilia Romagna, OIE Reference Laboratory for RHD, via Bianchi 9, 25124 Brescia, Italy.

Lagovirus is an emerging genus of Caliciviridae, which includes the Rabbit Hemorrhagic Disease Virus (RHDV) of rabbits and the European brown hare syndrome virus (EBHSV) of hares that cause lethal hepatitis. In 2010, a new RHDV related virus (RHDV2) with a unique genetic and antigenic profile and lower virulence was identified in France in rabbits. Here we report the identification of RHDV2 as the cause in Sardinia of several outbreaks of acute hepatitis in rabbits and Cape hare (Lepus capensis mediterraneus). This is the first account of a lagovirus that causes fatal hepatitis in both rabbits and hares.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1186/1297-9716-44-96DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3853023PMC
October 2013

Lipid profiles in brains from sheep with natural scrapie.

Chem Phys Lipids 2013 Oct-Nov;175-176:33-40. Epub 2013 Aug 16.

Department of Biomedical Sciences, University of Cagliari, Monserrato 09042, Italy. Electronic address:

Prion diseases are fatal neurodegenerative disorders affecting many mammals, ovine scrapie being the archetypal prion disease. Several independent studies in murine and cell-based models of scrapie have highlighted the presence of a link between prion generation and lipid alterations; yet, no data on natural disease are available. In this study we investigated levels of total lipids and cholesterol as well as profiles of fatty acids in brain homogenates from symptomatic and asymptomatic scrapie-infected sheep vs. healthy sheep, all belonging to the same flock. Lipid extracts were analyzed by means of gas chromatography and high performance liquid chromatography. Data of fatty acids were submitted to multivariate statistical analysis to give a picture of the brain lipid profiles of sheep. Interestingly, results revealed abnormalities in the brain fatty acid unsaturation of infected/symptomatic animals. Significant reduction of monoene 18:1 n-9 was detected in brain lipids from infected/symptomatic sheep, as compared to healthy and infected/asymptomatic animals, and this alteration occurred in combination with a significant increase in 18:0 level. The unsupervised Principal Component Analysis showed that infected/symptomatic and healthy sheep samples lie in two different regions of the plot, infected/asymptomatic lie mostly next to healthy. The increase of cerebral saturated fatty acids provides a rough indication of presumed alterations in lipid raft domains of nervous cells during scrapie, suggesting that they may exist in a notable viscous liquid-ordered state. Such physicochemical alteration would have a profound impact on the raft thermodynamic properties, its spatial organization, and signal transduction, all potentially relevant for prion generation.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1016/j.chemphyslip.2013.08.001DOI Listing
June 2014

A lympho-follicular microenvironment is required for pathological prion protein deposition in chronically inflamed tissues from scrapie-affected sheep.

PLoS One 2013 3;8(5):e62830. Epub 2013 May 3.

Dipartimento di Sanità Animale, Istituto Zooprofilattico Sperimentale della Sardegna, Sassari, Italy.

In sheep scrapie, pathological prion protein (PrP(Sc)) deposition occurs in the lymphoreticular and central nervous systems. We investigated PrP(Sc) distribution in scrapie-affected sheep showing simultaneous evidence of chronic lymphofollicular, lymphoproliferative/non-lymphofollicular, and/or granulomatous inflammations in their mammary gland, lung, and ileum. To do this, PrP(Sc) detection was carried out via immunohistochemistry and Western Blotting techniques, as well as through inflammatory cell immunophenotyping. Expression studies of gene coding for biological factors modulating the host's inflammatory response were also carried out. We demonstrated that ectopic PrP(Sc) deposition occurs exclusively in the context of lymphofollicular inflammatory sites, inside newly formed and well-organized lymphoid follicles harboring follicular dendritic cells. On the contrary, no PrP(Sc) deposition was detected in granulomas, even when they were closely located to newly formed lymphoid follicles. A significantly more consistent expression of lymphotoxin α and β mRNA was detected in lymphofollicular inflammation compared to the other two types, with lymphotoxin α and β signaling new lymphoid follicles' formation and, likely, the occurrence of ectopic PrP(Sc) deposition inside them. Our findings suggest that, in sheep co-affected by scrapie and chronic inflammatory conditions, only newly formed lymphoid follicles provide a suitable micro-environment that supports the scrapie agent's replication in inflammatory sites, with an increased risk of prion shedding through body secretions/excretions.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://journals.plos.org/plosone/article?id=10.1371/journal.pone.0062830PLOS
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3643908PMC
November 2013

Pathology in practice. Epitheliogenesis imperfecta in a lamb.

J Am Vet Med Assoc 2013 Jan;242(2):179-81

Istituto Zooprofilattico Sperimentale della Sardegna G. Pegreffi, 07100 Sassari, Italy.

View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.2460/javma.242.2.179DOI Listing
January 2013

Magnetic resonance imaging of the brain and skull of sheep with cerebral coenurosis.

Am J Vet Res 2012 Dec;73(12):1913-8

Dipartimento di Medicina Veterinaria, Facoltà di Medicina Veterinaria, Università degli Studi di Sassari, 07100 Sassari, Italy.

Objective: To determine MRI characteristics of the skulls and brains of sheep with chronic cerebral coenurosis (CC) caused by naturally acquired Taenia multiceps infection.

Animals: 33 sheep with CC and 10 healthy control sheep.

Procedures: Sheep underwent MRI of the head. Volumes of the cranial cavity and rostral and caudal fossas of the cranial cavity were determined. For CC-affected sheep, the number, location, and volume of T multiceps cysts were determined and the percentage volumes of cysts in the cranial cavity and rostral and caudal fossas of the cranial cavity were calculated. Focal and diffuse abnormalities of cranial bones in CC-affected sheep were identified. Brain edema and hemorrhage and signs of increased cranial pressure (ICP) in MRI images were determined.

Results: Volumes of the cranial cavity and rostral and caudal fossas of the cranial cavity were significantly larger for CC-affected sheep versus healthy control sheep. Total volumes of cysts ranged from 4.40% to 46.93% in cranial cavities of sheep, 4.12% to 51.53% in rostral fossas of cranial cavities of sheep, and 15.24% to 68.30% in caudal fossas of cranial cavities of sheep. Moderate to severe diffuse cranial bone abnormalities and signs of increased ICP in MRI images were detected in 21 and 24 sheep, respectively, and were positively correlated with cyst volumes.

Conclusions And Clinical Relevance: Results suggested that cranial cavity volume and morphological abnormalities can be detected in sheep with CC. These changes may reflect abnormalities in ossification of the cranial bones secondary to chronically increased ICP caused by development of T multiceps cysts.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.2460/ajvr.73.12.1913DOI Listing
December 2012

Functionalized multiwalled carbon nanotubes as ultrasound contrast agents.

Proc Natl Acad Sci U S A 2012 Oct 24;109(41):16612-7. Epub 2012 Sep 24.

Dipartimento di Chimica e Farmacia, Sperimentale e Oncologica, Università degli Studi di Sassari, 07100 Sassari, Italy.

Ultrasonography is a fundamental diagnostic imaging tool in everyday clinical practice. Here, we are unique in describing the use of functionalized multiwalled carbon nanotubes (MWCNTs) as hyperechogenic material, suggesting their potential application as ultrasound contrast agents. Initially, we carried out a thorough investigation to assess the echogenic property of the nanotubes in vitro. We demonstrated their long-lasting ultrasound contrast properties. We also showed that ultrasound signal of functionalized MWCNTs is higher than graphene oxide, pristine MWCNTs, and functionalized single-walled CNTs. Qualitatively, the ultrasound signal of CNTs was equal to that of sulfur hexafluoride (SonoVue), a commercially available contrast agent. Then, we found that MWCNTs were highly echogenic in liver and heart through ex vivo experiments using pig as an animal model. In contrast to the majority of ultrasound contrast agents, we observed in a phantom bladder that the tubes can be visualized within a wide variety of frequencies (i.e., 5.5-10 MHz) and 12.5 MHz using tissue harmonic imaging modality. Finally, we demonstrated in vivo in the pig bladder that MWCNTs can be observed at low frequencies, which are appropriate for abdominal organs. Importantly, we did not report any toxicity of CNTs after 7 d from the injection by animal autopsy, organ histology and immunostaining, blood count, and chemical profile. Our results reveal the enormous potential of CNTs as ultrasound contrast agents, giving support for their future applications as theranostic nanoparticles, combining diagnostic and therapeutic modalities.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1073/pnas.1208312109DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3478634PMC
October 2012

Age, scrapie status, PrP genotype and follicular dendritic cells in ovine ileal Peyer's patches.

Res Vet Sci 2012 Oct 2;93(2):853-6. Epub 2011 Oct 2.

University of Teramo, Faculty of Veterinary Medicine, Department of Comparative Biomedical Sciences, Piazza Aldo Moro 45, 64100 Teramo, Italy.

Follicular dendritic cells (FDCs) residing within ileal Peyer's patches (PPs) are of crucial relevance for sheep scrapie early pathogenesis and subsequent scrapie prion neuroinvasion. In this study, ileal PP follicles were significantly more numerous in lambs than in adult Sarda breed sheep, with significant differences being also found in lymphoid follicle area, perimeter and FDC density. Furthermore, PrPd deposition within ileal PPs and host's PrP genotype did not significantly influence these parameters. We conclude that age significantly affects FDC density in ileal PPs from Sarda breed ovines, independently from host's scrapie status and PrP genotype.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1016/j.rvsc.2011.09.002DOI Listing
October 2012

Comparative performance of three TSE rapid tests for surveillance in healthy sheep affected by scrapie.

J Virol Methods 2011 May 21;173(2):161-8. Epub 2011 Jan 21.

CEA - Istituto Zooprofilattico Sperimentale del Piemonte Liguria e Valle d'Aosta, Via Bologna 148, 10154 Turin, Italy.

Rapid tests specific for sheep and goats became part of European Union-wide active scrapie surveillance in 2006. Performance of three approved TSE rapid tests for the detection of sheep infected with scrapie in field cases in the pre-clinical stage of the disease was compared. The medulla oblongata of 969 asymptomatic sheep of various genotype and breed aged over 18 months from 23 Italian flocks affected with scrapie, were tested by the Bio-Rad TeSeE Sheep/Goat (A), the IDEXX HerdChek BSE-Scrapie Antigen Test Kit, EIA (B) and the Prionics(®)-Check Western Small Ruminant (C) rapid tests. Of 136 positive samples of classical scrapie, as confirmed by Western blot assay, 132 were positive with test A (Se 97.06%, CI 95% 92.64-99.19); 135 with test B (Se 99.26%, 95% CI 95.97-99.98) and 128 with test C (Se 94.12%, 95% CI 88.74-97.43). Tests A and B showed the best performance on analytical sensitivity. All three systems demonstrated good reproducibility: being the intrarater and interrater kappa coefficients always over 0.83. The one available atypical scrapie sample was positive with tests A and B, negative with test C. Considering the discrepant results in the detection of low PrP(sc) concentrations and of the atypical case, differences can be expected in the efficacy of an active surveillance system, depending on the test adopted.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1016/j.jviromet.2011.01.008DOI Listing
May 2011

Sheep with scrapie and mastitis transmit infectious prions through the milk.

J Virol 2011 Jan 17;85(2):1136-9. Epub 2010 Nov 17.

Istituto Zooprofilattico Sperimentale della Sardegna, Sassari, Italy.

Prions are misfolded proteins that are infectious and naturally transmitted, causing a fatal neurological disease in humans and animals. Prion shedding routes have been shown to be modified by inflammation in excretory organs, such as the kidney. Here, we show that sheep with scrapie and lentiviral mastitis secrete prions into the milk and infect nearly 90% of naïve suckling lambs. Thus, lentiviruses may enhance prion transmission, conceivably sustaining prion infections in flocks for generations. This study also indicates a risk of prion spread to sheep and potentially to other animals through dietary exposure to pooled sheep milk or milk products.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1128/JVI.02022-10DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3020009PMC
January 2011

Association of N176K and L141F dimorphisms of the PRNP gene with lack of pathological prion protein deposition in placentas of naturally and experimentally scrapie-affected ARQ/ARQ sheep.

J Gen Virol 2010 Sep 12;91(Pt 9):2402-7. Epub 2010 May 12.

Istituto Zooprofilattico Sperimentale della Sardegna, 07100 Sassari, Italy.

The placenta is important in the horizontal transmission of the aetiological agent in scrapie-affected sheep. It has been demonstrated that the placentas of fetuses carrying the dimorphism Q171R of the PRNP gene is resistant to pathological prion protein (PrP(Sc)) accumulation in the placenta. To test whether other PRNP polymorphisms are associated with a lack of placental PrP(Sc) deposition, we carried out a study on 26 naturally and 11 experimentally scrapie-affected ewes with or without clinical signs. PrP(Sc) was detected in the placenta of ARQ/ARQ(wild type) fetuses by Western blot and immunohistochemical analysis, but not in ARQN(176)/ARQK(176) or, as expected, ARQ/ARR samples. Furthermore, three of four AL(141)RQ/AF(141)RQ placentas were also PrP(Sc) negative, suggesting that the dimorphism at codon 141 may also mediate placental deposition of PrP(Sc). This finding demonstrates for the first time that fetal PRNP polymorphisms, other than those at codon 171, are associated with the lack of placental deposition of PrP(Sc).
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1099/vir.0.021188-0DOI Listing
September 2010

Human variant Creutzfeldt-Jakob disease and sheep scrapie PrP(res) detection using seeded conversion of recombinant prion protein.

Protein Eng Des Sel 2009 Aug 1;22(8):515-21. Epub 2009 Jul 1.

Laboratory of Persistent Viral Diseases, National Institute for Allergy and Infectious Diseases, National Institutes of Health, Rocky Mountain Laboratories, 903 S. 4th St., Hamilton, MT 59840, USA.

The pathological isoform of the prion protein (PrP(res)) can serve as a marker for prion diseases, but more practical tests are needed for preclinical diagnosis and sensitive detection of many prion infections. Previously we showed that the quaking-induced conversion (QuIC) assay can detect sub-femtogram levels of PrP(res) in scrapie-infected hamster brain tissue and distinguish cerebral spinal fluid (CSF) samples from normal and scrapie-infected hamsters. We now report the adaptation of the QuIC reaction to prion diseases of medical and agricultural interest: human variant Creutzfeldt-Jakob disease (vCJD) and sheep scrapie. PrP(res)-positive and -negative brain homogenates from humans and sheep were discriminated within 1-2 days with a sensitivity of 10-100 fg PrP(res). More importantly, in as little as 22 h we were able to distinguish CSF samples from scrapie-infected and uninfected sheep. These results suggest the presence of prions in CSF from scrapie-infected sheep. This new method enables the relatively rapid and sensitive detection of human CJD and sheep scrapie PrP(res) and may facilitate the development of practical preclinical diagnostic and high-throughput interference tests.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1093/protein/gzp031DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC2719501PMC
August 2009

Enteroglial and neuronal involvement without apparent neuron loss in ileal enteric nervous system plexuses from scrapie-affected sheep.

J Gen Virol 2007 Oct;88(Pt 10):2899-2904

Department of Comparative Biomedical Sciences, Faculty of Veterinary Medicine, University of Teramo, Teramo, Italy.

The enteric nervous system (ENS) probably plays a dominant role in sheep scrapie pathogenesis, but little is known about the cell types involved. We investigated the ileal myenteric and submucosal plexuses of four naturally and four orally experimentally scrapie-affected ARQ/ARQ Sarda sheep, as well as those of 12 healthy-control Sarda sheep carrying different PrP genotypes. All scrapie-affected animals, euthanized at clinical-disease end stage, showed PrPd deposition within enteric glial cells (EGCs) and calbindin-immunoreactive (CALB-IR) and neuronal nitric oxide synthase (nNOS)-IR neurons. Whole-mount investigations revealed no significant differences between the densities of total, CALB-IR and nNOS-IR neurons in scrapie-affected versus healthy sheep, irrespective of PrP genotype. Our results suggest that EGCs and CALB-IR and nNOS-IR neurons are probably involved in the pathogenesis of natural and oral experimental sheep scrapie. Furthermore, the infectious agent may be less pathogenic towards ENS neurons than it is towards central nervous system neurons.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1099/vir.0.82907-0DOI Listing
October 2007

Intraepithelial and interstitial deposition of pathological prion protein in kidneys of scrapie-affected sheep.

PLoS One 2007 Sep 12;2(9):e859. Epub 2007 Sep 12.

Istituto Zooprofilattico Sperimentale della Sardegna, Sassari, Italy.

Prions have been documented in extra-neuronal and extra-lymphatic tissues of humans and various ruminants affected by Transmissible Spongiform Encephalopathy (TSE). The presence of prion infectivity detected in cervid and ovine blood tempted us to reason that kidney, the organ filtrating blood derived proteins, may accumulate disease associated PrP(Sc). We collected and screened kidneys of experimentally, naturally scrapie-affected and control sheep for renal deposition of PrP(Sc) from distinct, geographically separated flocks. By performing Western blot, PET blot analysis and immunohistochemistry we found intraepithelial (cortex, medulla and papilla) and occasional interstitial (papilla) deposition of PrP(Sc )in kidneys of scrapie-affected sheep. Interestingly, glomerula lacked detectable signals indicative of PrP(Sc). PrP(Sc) was also detected in kidneys of subclinical sheep, but to significantly lower degree. Depending on the stage of the disease the incidence of PrP(Sc) in kidney varied from approximately 27% (subclinical) to 73.6% (clinical) in naturally scrapie-affected sheep. Kidneys from flocks without scrapie outbreak were devoid of PrP(Sc). Here we demonstrate unexpectedly frequent deposition of high levels of PrP(Sc) in ovine kidneys of various flocks. Renal deposition of PrP(Sc) is likely to be a pre-requisite enabling prionuria, a possible co-factor of horizontal prion-transmission in sheep.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://journals.plos.org/plosone/article?id=10.1371/journal.pone.0000859PLOS
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC1964536PMC
September 2007

Gene expression profiling on sheep brain reveals differential transcripts in scrapie-affected/not-affected animals.

Brain Res 2007 Apr 17;1142:217-22. Epub 2007 Jan 17.

Department of Food Safety and Veterinary Public Health, Istituto Superiore di Sanità, Rome, Italy.

This study aimed at identifying genes that could mark scrapie infection in the central nervous system of sheep. We used the subtractive suppressive hybridization (SSH) technique on brain samples from sheep healthy or clinically affected by scrapie. Following subtraction, several discrete differential bands appeared between the two reciprocally subtracted samples. These bands were cloned and sequenced, allowing identifying the genes COX1, CHN1, PPP2CA, LRFN5, CAMK2A and RABEPK. Two of the genes identified, CHN1 and RABEPK, appear to locate inside a QTL region known to modulate prion disease incubation time in mice, and LRFN5 maps inside a QTL region identified in sheep. Furthermore, CHN1 and RABEKP showed new unreported differential splicing.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1016/j.brainres.2007.01.033DOI Listing
April 2007

Molecular analysis of cases of Italian sheep scrapie and comparison with cases of bovine spongiform encephalopathy (BSE) and experimental BSE in sheep.

J Clin Microbiol 2003 Sep;41(9):4127-33

Laboratory of Veterinary Medicine, Istituto Superiore di Sanità Istituto Zooprofilattico Sperimentale del Lazio e della Toscana, Rome, Italy.

Concerns have been raised about the possibility that the bovine spongiform encephalopathy (BSE) agent could have been transmitted to sheep populations via contaminated feedstuffs. The objective of our study was to investigate the suitability of molecular strain typing methods as a surveillance tool for studying scrapie strain variations and for differentiating PrP(Sc) from sheep scrapie, BSE, and sheep BSE. We studied 38 Italian sheep scrapie cases from 13 outbreaks, along with a British scrapie case, an experimental ovine BSE, and 3 BSE cases, by analyzing the glycoform patterns and the apparent molecular masses of the nonglycosylated forms of semipurified, proteinase-treated PrP(Sc). Both criteria were able to clearly differentiate sheep scrapie from BSE and ovine experimental BSE. PrP(Sc) from BSE and sheep BSE showed a higher glycoform ratio and a lower molecular mass of the nonglycosylated form compared to scrapie PrP(Sc). Scrapie cases displayed homogeneous PrP(Sc) features regardless of breed, flock, and geographic origin. The glycoform patterns observed varied with the antibody used, but either a monoclonal antibody (MAb) (F99/97.6.1) or a polyclonal antibody (P7-7) was able to distinguish scrapie from BSE PrP(Sc). While more extensive surveys are needed to further corroborate these findings, our results suggest that large-scale molecular screening of sheep populations for BSE surveillance may be eventually possible.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC193806PMC
http://dx.doi.org/10.1128/jcm.41.9.4127-4133.2003DOI Listing
September 2003