Edoardo Pozio

Publications (103)310.91 Total impact

• Article: Global proteomic analysis of the oocyst/sporozoite of Toxoplasma gondii reveals commitment to a host-independent lifestyle.

  Alessia Possenti, Federica Fratini, Luca Fantozzi, Edoardo Pozio, Jitender P Dubey, Marta Ponzi, Elisabetta Pizzi, Furio Spano
  [show abstract] [hide abstract]
  ABSTRACT: BACKGROUND: Toxoplasmosis is caused by the apicomplexan parasite Toxoplasma gondii and can be acquired either congenitally or via the oral route. In the latter case, transmission is mediated by two distinct invasive stages, i.e., bradyzoites residing in tissue cysts or sporozoites contained in environmentally resistant oocysts shed by felids in their feces. The oocyst plays a central epidemiological role, yet this stage has been scarcely investigated at the molecular level and the knowledge of its expressed proteome is very limited. RESULTS: Using one-dimensional gel electrophoresis coupled to liquid chromatography-linked tandem mass spectrometry, we analysed total or fractionated protein extracts of partially sporulated T. gondii oocysts, producing a dataset of 1304 non reduntant proteins (~18% of the total predicted proteome), ~59% of which were classified according to the MIPS functional catalogue database. Notably, the comparison of the oocyst dataset with the extensively covered proteome of T. gondii tachyzoite, the invasive stage responsible for the clinical signs of toxoplasmosis, identified 154 putative oocyst/sporozoite-specific proteins, some of which were validated by Western blot. The analysis of this protein subset showed that, compared to tachyzoites, oocysts have a greater capability of de novo amino acid biosynthesis and are well equipped to fuel the Krebs cycle with the acetyl-CoA generated through fatty acid beta-oxidation and the degradation of branched amino acids. CONCLUSIONS: The study reported herein significantly expanded our knowledge of the proteome expressed by the oocyst/sporozoite of T. gondii, shedding light on a stage-specifc subset of proteins whose functional profile is consistent with the adaptation of T. gondii oocysts to the nutrient-poor and stressing extracellular environment. FREE ONLINE http://www.biomedcentral.com/1471-2164/14/183
  BMC Genomics 03/2013; 14(1):183. · 4.07 Impact Factor
• Article: Development of an ELISA to detect the humoral immune response to Trichinella zimbabwensis in Nile crocodiles (Crocodylus niloticus).

  Alessandra Ludovisi, Louis Jacobus La Grange, Maria Angeles Gómez Morales, Edoardo Pozio
  [show abstract] [hide abstract]
  ABSTRACT: Crocodiles are known reservoir hosts of Trichinella papuae and Trichinella zimbabwensis, two zoonotic parasites that also infect mammals. Since commercial crocodile farming represents a key source of income in several countries, it is important to monitor this nematode infection in both farmed crocodiles and in breeding stocks which are frequently introduced from the wild. For this purpose, an indirect ELISA was developed to detect the anti-Trichinella immune response in crocodile sera. New Zealand rabbits were immunized with pooled sera from non-infected farmed crocodiles in the presence of Freund's complete adjuvant. The anti-crocodile serum was then conjugated with horseradish peroxidase. Serum samples from four Nile crocodiles (Crocodylus niloticus) experimentally infected with T. zimbabwensis and from four uninfected crocodiles were used to set up the ELISA. The larval burden per gram of muscle tissue was determined by muscle biopsy. The test was performed on serum samples from an additional 15 experimentally infected crocodiles as well as eight wild Nile crocodiles. Among the 19 experimentally infected crocodiles, seroconversion was observed in 11 animals. The highest antibody response was observed six weeks post infection (p.i.), but in most of these animals, antibodies were not detectable after six weeks p.i. even though live larvae were present in the muscles up to six months p.i.
  Veterinary Parasitology 02/2013; · 2.58 Impact Factor
• Article: Molecular identification of nematode larvae different from those of the Trichinella genus detected by muscle digestion.

  Gianluca Marucci, Maria Interisano, Giuseppe La Rosa, Edoardo Pozio
  [show abstract] [hide abstract]
  ABSTRACT: Although larvae of the genus Trichinella are the most common parasite species detected in vertebrate muscles using artificial digestion, nematode larvae belonging to other genera are sometimes detected and incorrectly identified as Trichinella. However, it is often very difficult to identify these larvae at the species, genus or family level using microscopy because of the absence of specific morphological characters or cuticle damage, and the only means of identification is PCR and sequencing of specific molecular markers (12S mtDNA; COI; 18S rDNA; and ITS1). From 2008 to 2011, 18 nematode isolates not belonging to the genus Trichinella were collected from different host species. Eleven of these isolates were successfully identified at the species, genus or superfamily level: larvae from two common kestrels, three hooded crows, a hen harrier and a domestic pig were identified as Toxocara cati; larvae from a badger were identified as Toxocara canis; larvae from a domestic pig were identified as a free-living nematode of the genus Panagrolaimus; larvae from a wild boar were identified as belonging to the Metastrongylus genus; and larvae from a rough-legged buzzard were identified as belonging to the superfamily Filarioidea. The recovery of nematodes belonging to genera other than Trichinella during routine meat inspection suggests that the persons performing the analyses need to be informed of the possibility of false positives and that a molecular-based identification system that allows for a rapid and reliable response must be adopted (i.e., a DNA barcoding-like system).
  Veterinary Parasitology 02/2013; · 2.58 Impact Factor
• Article: Validation of a latex agglutination test for the detection of Trichinella infections in pigs.

  Maria Interisano, Gianluca Marucci, Maria Angeles Gómez-Morales, Walter Glawischnig, Marleen Claes, Age Kärssin, Goran Zakrisson, Edoardo Pozio
  [show abstract] [hide abstract]
  ABSTRACT: An antigen detection kit (Trichin-L), based on latex agglutination and developed by the Bio-Rad company was validated at five European laboratories. The validation parameters included specificity, sensitivity, robustness and reproducibility. Specificity was evaluated by testing parasite antigens from five non-Trichinella parasites in addition to the Trichinella genus. To evaluate sensitivity, 10 pork samples spiked with 1, 3, 6 or 15 Trichinella larvae were tested in each laboratory. To evaluate the robustness of the test, the solubilized antigens were maintained at room temperature and tested at different times. Reproducibility was assessed in each laboratory using 40, 100g minced pork samples, each spiked with Trichinella spiralis. The use of larval homogenates obtained from the Trichin-L kit as a template for parasite identification at the species level by a multiplex PCR, was also evaluated. The results showed a high specificity and sensitivity where solubilized antigens maintained their stability and reactivity for up to three days. Reproducibility was high, as similar results were obtained in the five laboratories. The larval homogenates obtained using the Trichin-L kit were successfully used in multiplex PCRs to identify Trichinella species.
  Veterinary Parasitology 02/2013; · 2.58 Impact Factor
• Article: Opisthorchis felineus an emerging infection in Italy and its implication for the European Union.

  Edoardo Pozio, Orlando Armignacco, Fabrizio Ferri, Maria Angeles Gomez Morales
  [show abstract] [hide abstract]
  ABSTRACT: The liver fluke Opisthorchis felineus is one of the few zoonotic trematodes that circulates in the European Union (EU). It is transmitted from freshwater snails to fish and then to fish-eating mammals, including humans, in which it causes opisthorchiasis. In the 20th century, the majority of infections in humans have been reported in Eastern Europe (e.g., Belarus, Russia, and Ukraine) and Asia (Siberia). In EU in the last fifty years, the parasite has been detected in humans of Germany and Greece, and in red foxes, polecats, cats, dogs, fish and mollusks of Germany, Italy, Poland, Portugal and Spain. In Italy, six individual cases and eight outbreaks of opisthorchiasis were reported from 2003 to 2011, for a total of 211 confirmed infections in humans. All infected persons had consumed raw fillets of tench (Tinca tinca) fished from two lakes in central Italy, but some of infected people were tourists who developed the disease in their respective home-countries. In the past decade, it has become increasingly popular to consume raw marinated fillets of fish. The objective of this review is to show how a change in human food habits have caused an increased the transmission of O. felineus, which has probably been circulating in the EU yet in a silent form for many years.
  Acta tropica 01/2013; · 2.22 Impact Factor
• Article: Validation of an Excretory/Secretory Antigen Based-Elisa for the Diagnosis of Opisthorchis felineus Infection in Humans from Low Trematode Endemic Areas.

  Maria Angeles Gómez-Morales, Alessandra Ludovisi, Marco Amati, Edoardo Pozio
  [show abstract] [hide abstract]
  ABSTRACT: Since opisthorchiasis does not show pathognomonic signs or symptoms, physicians can have serious problems to make a differential diagnosis of this infection in non endemic areas, in particular when there is a simultaneous occurrence with other seasonal infections. Moreover, symptomatic infections due to O. felineus can last a few weeks and then the signs and symptoms disappear, but the worms survive in the bile ducts for years causing hepatobiliary diseases including hepatomegaly, cholangitis, fibrosis of the periportal system, cholecystitis, and gallstones. Consequently, an early diagnosis prevents chronicity and loss of working days. The detection of specific antibodies has been considered as a complementary tool to the fecal examination to establish the definitive diagnosis of this infection and for the follow up. Therefore the aim of this work was the development and validation of an enzyme-linked immunosorbent assay (ELISA) using excretory/secretory antigens (ESA) from O. felineus adult worms to detect anti-Opisthorchis IgG in human sera. A total of 370 human sera were tested: 144 sera from persons with a confirmed diagnosis of opisthorchiasis, 110 sera from healthy Italian people, and 116 sera from people with other parasitic or non-parasitic infections. Results were analyzed by receiver-operator characteristic (ROC) curve analysis. The accuracy of the test, calculated by the area under curve (AUC), yielded a 0.999 value, indicating the high performance of the test. The sensitivity was 100% (95% CI: 97.40% to 100%) and no false-negative sera were detected; the specificity was 99.09% (95% CI: 95.02% to 99.83%). The validated ELISA shows a good performance in terms of sensitivity, repeatability and reproducibility, and it is suitable to detect anti-Opisthorchis IgG in human sera for diagnostic purposes and for the follow up to assess the efficacy of drug treatment.
  PLoS ONE 01/2013; 8(5):e62267. · 4.09 Impact Factor
• Article: Cryptic and Asymptomatic Opisthorchis felineus Infections.

  Orlando Armignacco, Fabrizio Ferri, Maria Angeles Gomez Morales, Luciano Caterini, Edoardo Pozio
  [show abstract] [hide abstract]
  ABSTRACT: We describe the diagnostic difficulties experienced during an opisthorchiasis outbreak. Of 31 infected individuals, 61.3% were asymptomatic, and in the 12 symptomatic individuals, the duration of non-pathognomonic symptoms was shorter than 4 weeks. Serology by enzyme-linked immunosorbent assay and polymerase chain reaction fecal analysis were shown to be the most sensitive diagnostic tools.
  The American journal of tropical medicine and hygiene 12/2012; · 2.59 Impact Factor
• Source

  Available from: Fabio Tosini

  Dataset: striking image

  Ilaria Vanni, Simone Mario Cacciò, Lindy Van Lith, Marianne Lebbad, Staffan G Svä Rd, Edoardo Pozio, Fabio Tosini
• Article: A distinctive Western blot pattern to recognize Trichinella infections in humans and pigs.

  Maria Angeles Gómez-Morales, Alessandra Ludovisi, Marco Amati, Radu Blaga, Milena Zivojinovic, Mabel Ribicich, Edoardo Pozio
  [show abstract] [hide abstract]
  ABSTRACT: Trichinellosis is a zoonotic disease caused by parasites of the genus Trichinella, which have a cosmopolitan distribution. For diagnostic purposes, a confirmatory test for ELISA-positive human and pig sera such as Western blotting is required, due to the high number of ELISA false positive sera. The objective of this study was to identify the Trichinella-specific antigens most frequently recognized by sera from Trichinella-infected humans and pigs, so as to define a distinctive pattern of Trichinella infection in sera from infected hosts using Western blots which allow false positive sera to be distinguished from true positive sera. Using excretory/secretory antigens, 450 human sera were tested by Western blotting: 150 from persons with a confirmed diagnosis of trichinellosis and 300 from persons who did not have trichinellosis but who tested positive by ELISA (i.e., false positives). We also tested 210 pig sera: (i) 30 from pigs experimentally infected with Trichinella spiralis; (ii) 90 from naturally T. spiralis-infected pigs; and (iii) 90 from pigs not infected with Trichinella, as shown after artificial digestion of the diaphragm pillars, yet which tested positive by ELISA (i.e., false positives). All true positive sera (i.e., sera from persons with confirmed trichinellosis as well as sera from naturally and experimentally infected pigs), reacted with a three-band pattern ranging in size from 48-72kDa. A distinctive pattern for recognizing Trichinella spp. infections in humans and pigs by Western blots is defined; it shows a sensitivity of 100% and it allows sera from Trichinella-infected humans and pigs to be distinguished from sera from persons and pigs that were not infected with Trichinella spp. (100% specificity).
  International journal for parasitology 09/2012; · 3.39 Impact Factor
• Source

  Available from: Fabio Tosini

  Article: A rare Cryptosporidium parvum genotype associated with infection of lambs and zoonotic transmission in Italy.

  Simone M Cacciò, Anna Rosa Sannella, Valeria Mariano, Silvia Valentini, Franco Berti, Fabio Tosini, Edoardo Pozio
  [show abstract] [hide abstract]
  ABSTRACT: An outbreak of cryptosporidiosis occurred in a mixed sheep/cattle farm of Central Italy in October 2011. A total of 450 ovines (250 sheep and 200 lambs) and 140 bovines (130 cows and 10 calves) were housed in two separated units, at the time of the outbreak. About half of the lambs had diarrhea due to Cryptosporidium sp. with a mortality rate of 80%; calves were not infected. Genomic DNA was extracted from an archived slide and from fecal specimens, and the parasite was identified as Cryptosporidium parvum by PCR and sequence analysis at the CpA135 gene. Genotyping at the GP60 gene showed the presence of a very rare genotype, IIaA20G2R1. Shortly after the outbreak was identified, the son of the farm's owner, aged 18 months, experienced an acute gastroenteritis and was hospitalized due to recurrent episodes of diarrhea, fever, vomiting and lack of appetite. The feces tested negative for bacteria and viruses, whereas cryptosporidiosis was diagnosed by microscopy and an immunochromatographic test. Molecular typing identified the C. parvum genotype IIaA20G2R1 in the feces of the child. This is the first case of transmission of cryptosporidiosis in Italy involving lambs as source of oocysts infectious to humans.
  Veterinary Parasitology 08/2012; · 2.58 Impact Factor
• Article: Trichinella patagoniensis n. sp. (Nematoda), a new encapsulated species infecting carnivorous mammals in South America.

  Silvio J Krivokapich, Edoardo Pozio, Graciana M Gatti, Cinthia L Gonzalez Prous, Mabel Ribicich, Gianluca Marucci, Giuseppe La Rosa, Viviana Confalonieri
  [show abstract] [hide abstract]
  ABSTRACT: Until a few years ago, Trichinella spiralis was the only taxon of the genus Trichinella detected in both domestic and wild animals of South America. Recently, a new genotype, named Trichinella T12, was identified in cougars (Puma concolor) from Argentina, on the basis of molecular studies using mitochondrial and nuclear ribosomal markers. In the present study, cross-breeding experiments indicated that Trichinella T12 is reproductively isolated from all other encapsulated Trichinella spp. and suggested that it is biologically more similar to Trichinella britovi and Trichinella murrelli than to the other encapsulated species/genotypes. Biological assays revealed that the reproductive capacity index of Trichinella T12 was ∼4 and >2000 times lower than those of T. spiralis in mice and rats, respectively. The reproductive capacity index of Trichinella T12 in domestic pigs ranged from 0.0 to 0.05. Larvae parasitising the muscles of carnivores were infective to mice after freezing at -5°C for 3months, but they lost infectivity after freezing at -18°C for 1week. The region within the rDNA, known as the expansion segment V, showed a unique sequence which differs from those of all other known Trichinella spp./genotypes. The biological, geographical and molecular data support the classification of the genotype Trichinella T12 as a new species widespread in the Neotropical region, for which we propose the name Trichinella patagoniensis n. sp.
  International journal for parasitology 08/2012; 42(10):903-10. · 3.39 Impact Factor
• Article: Detection of Giardia duodenalis Assemblages A and B in Human Feces by Simple, Assemblage-Specific PCR Assays.

  Ilaria Vanni, Simone Mario Cacciò, Lindy van Lith, Marianne Lebbad, Staffan G Svärd, Edoardo Pozio, Fabio Tosini
  [show abstract] [hide abstract]
  ABSTRACT: The flagellated protozoan Giardia duodenalis is a common gastrointestinal parasite of mammals, including humans. Molecular characterizations have shown the existence of eight genetic groups (or assemblages) in the G. duodenalis species complex. Human infections are caused by assemblages A and B, which infect other mammals as well. Whether transmission routes, animal reservoirs and associations with specific symptoms differ for assemblage A and assemblage B is not clear. Furthermore, the occurrence and clinical significance of mixed (A+B) infections is also poorly understood. To date, the majority of PCR assays has been developed to identify all G. duodenalis assemblages based on the use of primers that bind to conserved regions, yet a reliable identification of specific assemblages is better achieved by ad hoc methods. The aim of this work was to design simple PCR assays that, based on the use of assemblage-specific primers, produce diagnostic bands of different lengths for assemblage A and B. We first generated novel sequence information from assemblage B, identified homologous sequences in the assemblage A genome, and designed primers at six independent loci. Experiments performed on DNA extracted from axenic cultures showed that two of the six assays can detect the equivalent of a single cyst and are not negatively influenced by disproportions between DNA of each assemblage, at least up to a 9∶1 ratio. Further experiments on DNAs extracted from feces showed that the two assays can detect both assemblages in single tube reactions with excellent reliability. Finally, the robustness of these assays was demonstrated by testing a large collection of human isolates previously typed by multi-locus genotyping.
  PLoS Neglected Tropical Diseases 08/2012; 6(8):e1776. · 4.69 Impact Factor
• Source

  Available from: Fabio Tosini

  Article: Detection of Giardia duodenalis Assemblages A and B in Human Feces by Simple, Assemblage-Specific PCR Assays

  Ilaria Vanni, Simone Mario Cacciò, Lindy Van Lith, Marianne Lebbad, Staffan G Svä Rd, Edoardo Pozio, Fabio Tosini
  [show abstract] [hide abstract]
  ABSTRACT: The flagellated protozoan Giardia duodenalis is a common gastrointestinal parasite of mammals, including humans. Molecular characterizations have shown the existence of eight genetic groups (or assemblages) in the G. duodenalis species complex. Human infections are caused by assemblages A and B, which infect other mammals as well. Whether transmission routes, animal reservoirs and associations with specific symptoms differ for assemblage A and assemblage B is not clear. Furthermore, the occurrence and clinical significance of mixed (A+B) infections is also poorly understood. To date, the majority of PCR assays has been developed to identify all G. duodenalis assemblages based on the use of primers that bind to conserved regions, yet a reliable identification of specific assemblages is better achieved by ad hoc methods. The aim of this work was to design simple PCR assays that, based on the use of assemblage-specific primers, produce diagnostic bands of different lengths for assemblage A and B. We first generated novel sequence information from assemblage B, identified homologous sequences in the assemblage A genome, and designed primers at six independent loci. Experiments performed on DNA extracted from axenic cultures showed that two of the six assays can detect the equivalent of a single cyst and are not negatively influenced by disproportions between DNA of each assemblage, at least up to a 9:1 ratio. Further experiments on DNAs extracted from feces showed that the two assays can detect both assemblages in single tube reactions with excellent reliability. Finally, the robustness of these assays was demonstrated by testing a large collection of human isolates previously typed by multi-locus genotyping.
  PLoS Neglected Tropical Diseases 08/2012; 6(8):e1776. · 4.69 Impact Factor
• Source

  Available from: Fabio Tosini

  Article: Pigs as natural hosts of Dientamoeba fragilis genotypes found in humans.

  Simone M Cacciò, Anna Rosa Sannella, Elisabetta Manuali, Fabio Tosini, Marco Sensi, Daniele Crotti, Edoardo Pozio
  [show abstract] [hide abstract]
  ABSTRACT: Dientamoeba fragilis is a common intestinal parasite in humans. Transmission routes and natural host range are unknown. To determine whether pigs are hosts, we analyzed 152 fecal samples by microscopy and molecular methods. We confirmed that pigs are a natural host and harbor genotypes found in humans, suggesting zoonotic potential.
  Emerging Infectious Diseases 05/2012; 18(5):838-41. · 6.79 Impact Factor
• Article: Interaction network of the 14-3-3 protein in the ancient protozoan parasite Giardia duodenalis.

  Marco Lalle, Serena Camerini, Serena Cecchetti, Ahmed Sayadi, Marco Crescenzi, Edoardo Pozio
  [show abstract] [hide abstract]
  ABSTRACT: 14-3-3s are phosphoserine/phosphotreonine binding proteins that play pivotal roles as regulators of multiple cellular processes in eukaryotes. The flagellated protozoan parasite Giardia duodenalis, the causing agent of giardiasis, is a valuable simplified eukaryotic model. A single 14-3-3 isoform (g14-3-3) is expressed in Giardia, and it is directly involved in the differentiation of the parasite into cyst. To define the overall functions of g14-3-3, the protein interactome has been investigated. A transgenic G. duodenalis strain was engineered to express a FLAG-tagged g14-3-3 under its own promoter. Affinity chromatography coupled with tandem mass spectrometry analysis have been used to purify and identify FLAG-g14-3-3-associated proteins from trophozoites and encysting parasites. A total of 314 putative g14-3-3 interaction partners were identified, including proteins involved in several pathways. Some interactions seemed to be peculiar of one specific stage, while others were shared among the different stages. Furthermore, the interaction of g14-3-3 with the giardial homologue of the CDC7 protein kinase (gCDC7) was characterized, leading to the identification of a multiprotein complex containing not only g14-3-3 and gCDC7 but also a newly identified and highly divergent homologue of DBF4, the putative regulatory subunit of gCDC7. The relevance of g14-3-3 interactions in G. duodenalis biology was discussed.
  Journal of Proteome Research 03/2012; 11(5):2666-83. · 5.11 Impact Factor
• Article: Evidence of host-associated populations of Cryptosporidium parvum in Italy.

  Rosanna Drumo, Giovanni Widmer, Liam J Morrison, Andy Tait, Vincenzo Grelloni, Nicoletta D'Avino, Edoardo Pozio, Simone M Cacciò
  [show abstract] [hide abstract]
  ABSTRACT: Recent studies have revealed extensive genetic variation among isolates of Cryptosporidium parvum, an Apicomplexan parasite that causes gastroenteritis in both humans and animals worldwide. The parasite's population structure is influenced by the intensity of transmission, the host-parasite interaction, and husbandry practices. As a result, C. parvum populations can be panmictic, clonal, or even epidemic on both a local scale and a larger geographical scale. To extend the study of C. parvum populations to an unexplored region, 173 isolates of C. parvum collected in Italy from humans and livestock (calf, sheep, and goat) over a 10-year period were genotyped using a multilocus scheme based on 7 mini- and microsatellite loci. In agreement with other studies, extensive polymorphism was observed, with 102 distinct multilocus genotypes (MLGs) identified among 173 isolates. The presence of linkage disequilibrium, the confinement of MLGs to individual farms, and the relationship of many MLGs inferred using network analysis (eBURST) suggest a predominantly clonal population structure, but there is also evidence that part of the diversity can be explained by genetic exchange. MLGs from goats were found to differ from bovine and sheep MLGs, supporting the existence of C. parvum subpopulations. Finally, MLGs from isolates collected between 1997 and 1999 were also identified as a distinct subgroup in principal-component analysis and eBURST analysis, suggesting a continuous introduction of novel genotypes in the parasite population.
  Applied and environmental microbiology 03/2012; 78(10):3523-9. · 3.69 Impact Factor
• Article: Genetic variability of Echinococcus granulosus sensu stricto in Europe inferred by mitochondrial DNA sequences.

  Adriano Casulli, Maria Interisano, Tamas Sreter, Lidia Chitimia, Zvezdelina Kirkova, Giuseppe La Rosa, Edoardo Pozio
  [show abstract] [hide abstract]
  ABSTRACT: The genetic diversity of Echinococcus granulosus sensu stricto (s.s.) metacestodes from four European countries was evaluated by the DNA sequence analysis of the cytochrome c oxidase subunit 1 (cox1) mitochondrial gene. Of the 312 organisms investigated, 132 were from Bulgaria, 35 from Hungary, 89 from Italy and 56 from Romania. Considerable intraspecific variation was observed in the mitochondrial cox1 sequences: 24 haplotypes were detected in the Eastern European population and seven in the Italian population. The Eastern European population parsimony network displayed a star-like features consisting of the most common haplotype EG1 (G1 genotype) and the three major haplotypes: EG2, EG3 and EG4. The EG1 was also the major haplotype in the Italian population network, though with a higher prevalence (73%) compared to the Eastern European network. The percentage of the population constituted by the G1 genotype was used as an indirect index to evaluate the genetic diversity within E. granulosus s.s. populations of Eurasia. A clinal correlation between the percentage of the G1 genotype and the geographical regions of Eurasia was observed: the G1 genotype is highly represented in the Mediterranean Basin; it decreases in Eastern Europe and South-West Asia and increases in China. This clinal correlation could reflect the spreading of livestock domestication from Southern-Western Asia during the Neolithic period, beginning around 12,000 BC.
  Infection, genetics and evolution: journal of molecular epidemiology and evolutionary genetics in infectious diseases 03/2012; 12(2):377-83. · 3.22 Impact Factor
• Article: Development of a single larva microsatellite analysis to investigate the population structure of Trichinella spiralis.

  Giuseppe La Rosa, Gianluca Marucci, Benjamin M Rosenthal, Edoardo Pozio
  [show abstract] [hide abstract]
  ABSTRACT: Trichinella spiralis is the most important etiological agent of human trichinellosis. It has a cosmopolitan distribution and is transmitted to humans mainly through the consumption of pork. In nature, transmission occurs among animals through the ingestion of an infected carcass by one or more hosts. Microsatellite markers have provided insight into how T. spiralis dispersed geographically over its evolutionary history. The objectives of the present study were to develop microsatellite markers capable of differentiating single larvae for investigating the inter- and intra-specific population structure of T. spiralis and to determine their usefulness as genetic markers to study transmission mechanisms of this zoonotic parasite. A panel of 48 larvae derived from each of 22 distinct isolates originating from the Americas, Asia and Europe, were investigated. A total of 27 alleles were detected in these samples using seven new markers. The sequences of the amplified fragments containing the microsatellites support the homology of the amplified products and validate their use for genetic population studies. We documented the first known occurrence of a genetically variable larval admixture, indicating that more than two adults gave rise to the ensuing population of this host's muscle larvae. Globally, T. spiralis was observed to harbor less genetic variation than other nematodes, a result consistent with previous assays of nuclear and mitochondrial variation.
  Infection, genetics and evolution: journal of molecular epidemiology and evolutionary genetics in infectious diseases 03/2012; 12(2):369-76. · 3.22 Impact Factor
• Article: Genotyping Giardia duodenalis isolates from dogs: lessons from a multilocus sequence typing study.

  Relja Beck, Hein Sprong, Edoardo Pozio, Simone M Cacciò
  [show abstract] [hide abstract]
  ABSTRACT: Giardiasis is a common infection of dogs, and the occurrence of both zoonotic and host-adapted assemblages of Giardia duodenalis is well documented in this host. In the current study, G. duodenalis isolates from dogs collected in Croatia from both private owners (n=44) and kennels (n=52) were analyzed at four genetic loci: the ITS1-5.8S-ITS2 (ITS), the glutamate dehydrogenase (gdh), the triosephosphate isomerase (tpi), and the beta-giardin (bg). Both generic and assemblage D specific primers were used for the amplification of the tpi gene. All data were stored in a dedicated database, and analyzed to evaluate (1) the rate of amplification of G. duodenalis DNA from dogs at the four loci; (2) the distribution of assemblages and the occurrence of mixed infections; (3) the genetic variability at the intra-assemblage level; and (4) the zoonotic potential. We found that only half of the isolates could be amplified at either the gdh or the bg gene, whereas the combined use of generic and D-specific tpi primers yielded the highest amplification rate (85%). Sequence analysis showed that assemblages C and D are largely predominant in both kennel and household dogs, thus suggesting a minor role of dogs in zoonotic transmission of giardiasis. However, in many kennel dogs, incongruent results were obtained by using different markers, a result that is more likely explained by mixed infections rather than by genetic recombination. Phylogenetic analysis based on single or multiple loci failed to reveal the presence of distinct subpopulations within assemblages C and D. Our study illustrates the problems associated with the characterization of G. duodenalis isolates from dogs, and it casts doubts on the interpretation of genotyping results based on the analysis of single markers. We concluded that the current typing scheme is not suited to distinguish between recombinants and mixed infections in field isolates.
  Vector borne and zoonotic diseases (Larchmont, N.Y.) 03/2012; 12(3):206-13. · 2.61 Impact Factor
• Article: Molecular characterisation of a Cryptosporidium parvum rhoptry protein candidate related to the rhoptry neck proteins TgRON1 of Toxoplasma gondii and PfASP of Plasmodium falciparum.

  Elisabetta Valentini, Simona Cherchi, Alessia Possenti, Jean-François Dubremetz, Edoardo Pozio, Furio Spano
  [show abstract] [hide abstract]
  ABSTRACT: Given the lack of knowledge on the rhoptry proteins of Cryptosporidium parvum, we searched for putative members of this protein class in the CryptoDB database using as queries known Toxoplasma gondii rhoptry molecules. We cloned a C. parvum sporozoite cDNA of 4269bp encoding the sushi domain-containing protein cgd8_2530, which shared low amino acid sequence identity, yet a highly conserved domain architecture with the rhoptry neck proteins TgRON1 of T. gondii and PfASP of Plasmodium falciparum. On denaturing and native gels, cgd8_2530 migrated at approximately 150 and 1000 kDa, respectively, suggesting an involvement in a multi-subunit protein complex. Immunoflorescence localised cgd8_2530 to a single, elongated area anterior to sporozoite micronemes and showed protein relocation to the parasite-host cell interface in early epicellular stages. Our data strongly suggest a rhoptry localization for the newly characterised protein, which was therefore renamed C. parvum putative rhoptry protein-1 (CpPRP1).
  Molecular and Biochemical Parasitology 02/2012; 183(1):94-9. · 2.55 Impact Factor