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Genes Oct 2022The helminth parasites, and , are the causative agents of fasciolosis, a global and economically important disease of people and their livestock. Proteases are pivotal...
The helminth parasites, and , are the causative agents of fasciolosis, a global and economically important disease of people and their livestock. Proteases are pivotal to an array of biological processes related to parasitism (development, feeding, immune evasion, virulence) and therefore their action requires strict regulation by parasite anti-proteases (protease inhibitors). By interrogating the current publicly available spp. large sequencing datasets, including several genome assemblies and life cycle stage-specific transcriptome and proteome datasets, we reveal the complex profile and structure of proteases and anti-proteases families operating at various stages of the parasite's life cycle. Moreover, we have discovered distinct profiles of peptidases and their cognate inhibitors expressed by the parasite stages in the intermediate snail host, reflecting the different environmental niches in which they move, develop and extract nutrients. Comparative genomics revealed a similar cohort of peptidase inhibitors in and but a surprisingly reduced number of cathepsin peptidases genes in the genome assemblies. Chromosomal location of the genes provides new insights into the evolution of these gene families, and critical data for the future analysis and interrogation of spp. hybrids spreading throughout the Asian and African continents.
Topics: Animals; Fasciola; Fasciola hepatica; Parasites; Peptide Hydrolases; Virulence; Proteome; Life Cycle Stages; Protease Inhibitors; Cathepsins
PubMed: 36292739
DOI: 10.3390/genes13101854 -
Frontiers in Cellular and Infection... 2021Trematode parasites of the genus are the cause of liver fluke disease (fasciolosis) in humans and their livestock. Infection of the host involves invasion through the... (Review)
Review
Trematode parasites of the genus are the cause of liver fluke disease (fasciolosis) in humans and their livestock. Infection of the host involves invasion through the intestinal wall followed by migration in the liver that results in extensive damage, before the parasite settles as a mature egg-laying adult in the bile ducts. Genomic and transcriptomic studies revealed that increased metabolic stress during the rapid growth and development of is balanced with the up-regulation of the thiol-independent antioxidant system. In this cascade system thioredoxin/glutathione reductase (TGR) reduces thioredoxin (Trx), which then reduces and activates peroxiredoxin (Prx), whose major function is to protect cells against the damaging hydrogen peroxide free radicals. expresses a single TGR, three Trx and three Prx genes; however, the transcriptional expression of Trx1 and Prx1 far out-weighs (>50-fold) other members of their family, and both are major components of the parasite secretome. While Prx1 possesses a leader signal peptide that directs its secretion through the classical pathway and explains why this enzyme is found freely soluble in the secretome, Trx1 lacks a leader peptide and is secreted an alternative pathway that packages the majority of this enzyme into extracellular vesicles (EVs). Here we propose that Prx1 and Trx1 do not function as part of the parasite's stress-inducible thiol-dependant cascade, but play autonomous roles in defence against the general anti-pathogen oxidative burst by innate immune cells, in the modulation of host immune responses and regulation of inflammation.
Topics: Animals; Antioxidants; Fasciola hepatica; Fascioliasis; Humans; Peroxiredoxins; Thioredoxins
PubMed: 34026663
DOI: 10.3389/fcimb.2021.667272 -
PLoS Neglected Tropical Diseases Jun 2021Fascioliasis is a zoonotic trematode infection that is endemic in the highlands of Peru. Chronic fascioliasis can be asymptomatic and remain undiagnosed for years....
Fascioliasis is a zoonotic trematode infection that is endemic in the highlands of Peru. Chronic fascioliasis can be asymptomatic and remain undiagnosed for years. Chronic malnutrition in children, as manifested by stunting, leads to delayed cognitive development and lost productivity. We hypothesized that fascioliasis is among the factors associated with stunting in children from endemic areas. We conducted a cross-sectional study among children attending pre-school and school in 26 communities in the Anta province in the Cusco region of Peru. We conducted interviews to collect information on demographic, socioeconomic, and medical history. Blood was collected and tested for complete cell count and FAS2 ELISA for Fasciola antibodies. Three stool samples per participant were tested for parasites by Kato-Katz and Lumbreras rapid sedimentation methods. Chronic fascioliasis was determined by the presence of ova in stool. Children's height, weight, and age were recorded and used to calculate height for age Z scores (HAZ). Three thousand children participated in the study. Nine percent (264) of children had at least one positive test for Fasciola infection, 6% (164) had chronic fascioliasis, and 3% (102) had only positive antibody tests. The median HAZ was -1.41 (IQR: -2.03 to -0.81) and was similar in males and females. Twenty six percent (776) of children had stunting with HAZ < -2. Children with chronic fascioliasis had a lower median HAZ than children without Fasciola (-1.54 vs. -1.4, p = 0.014). History of treatment for malnutrition, history of treatment for anemia, having other helminths in stool, lower socioeconomic score, living at a higher elevation, and fewer years of schooling of both parents were associated with a lower HAZ score. In a multiple regression analysis, older age and a lower socioeconomic score were associated with a lower HAZ score. While fascioliasis and other helminths were associated with lower HAZ, they were not independent of the socioeconomic score.
Topics: Adolescent; Altitude; Anemia; Animals; Antibodies, Helminth; Child; Child Nutrition Disorders; Child, Preschool; Cross-Sectional Studies; Fasciola; Fascioliasis; Feces; Female; Growth Disorders; Helminths; Humans; Male; Peru; Socioeconomic Factors
PubMed: 34153050
DOI: 10.1371/journal.pntd.0009519 -
Equine Veterinary Journal Mar 2020Fasciola hepatica (liver fluke) affects grazing animals including horses but the extent to which it affects UK horses is unknown.
BACKGROUND
Fasciola hepatica (liver fluke) affects grazing animals including horses but the extent to which it affects UK horses is unknown.
OBJECTIVES
To define how liver fluke affects the UK horse population.
STUDY DESIGN
Descriptive, cross-sectional, observational study.
METHODS
An F. hepatica excretory-secretory antibody detection ELISA with a diagnostic sensitivity of 71% and specificity of 97% was validated and used to analyse serum samples. An abattoir study was performed to determine prevalence. A case-control study of 269 horses compared fluke exposure between horses with liver disease and controls. Data on clinical signs and blood test results were collected for sero-positive horses. Genotyping of adult fluke was used to produce a multilocus genotype for each parasite.
RESULTS
Four (2.2%) of 183 horses registered in the UK, sampled in the abattoir, had adult flukes in the liver, and the sero-prevalence of F. hepatica was estimated as 8.7%. In the case-control study, horses showing signs consistent with liver disease had significantly higher odds of testing positive for F. hepatica on ELISA than control horses. In 23 sero-positive horses, a range of non-specific clinical signs and blood test abnormalities was reported, with a third of the horses showing no signs. Genotypic analysis of liver flukes from horses provided evidence that these came from the same population as flukes from sheep and cattle.
MAIN LIMITATIONS
Bias could have arisen in the prevalence and case-control studies due to convenience sampling methods, in particular the geographic origin of the horses. Only a small number of horses tested positive so the data on clinical signs are limited.
CONCLUSIONS
Exposure to liver fluke occurs frequently in horses and may be an under-recognised cause of liver disease. Flukes isolated from horses are from the same population as those found in ruminants. When designing and implementing parasite control plans, fluke should be considered, and horses should be tested if appropriate.
Topics: Animals; Case-Control Studies; Cattle; Cross-Sectional Studies; Fasciola hepatica; Fascioliasis; Horses; Sheep; United Kingdom
PubMed: 31254486
DOI: 10.1111/evj.13149 -
Parasitology Research Aug 2021Fascioliasis is a foodborne trematode endemic worldwide. Children under 15 years have the highest prevalence of infection. We hypothesized that acute fascioliasis would...
Fascioliasis is a foodborne trematode endemic worldwide. Children under 15 years have the highest prevalence of infection. We hypothesized that acute fascioliasis would be associated with more pronounced cytokine changes than in chronic disease or no helminth infections. To test this hypothesis, 33 children who lived in the Peruvian highlands were classified into 3 groups: acute fascioliasis, chronic fascioliasis, and no helminth infection. Type Th1, Th2, and Th17 cytokines were measured in plasma by cytometric bead array. Children with acute infection had higher levels of IL-5 and IL-17 compared with controls (p < 0.001 and p < 0.007, respectively). The increased IL-5 plasma concentration in children with acute infection was associated with the eosinophilia found in that group.
Topics: Animals; Child; Cytokines; Fasciola hepatica; Fascioliasis; Humans; Interleukin-5; Peru; Th17 Cells
PubMed: 34245363
DOI: 10.1007/s00436-021-07230-8 -
PLoS Pathogens Jan 2018Schistosomes are blood-dwelling trematodes with global impact on human and animal health. Because medical treatment is currently based on a single drug, praziquantel,... (Review)
Review
Schistosomes are blood-dwelling trematodes with global impact on human and animal health. Because medical treatment is currently based on a single drug, praziquantel, there is urgent need for the development of alternative control strategies. The Schistosoma mansoni genome project provides a platform to study and connect the genetic repertoire of schistosomes to specific biological functions essential for successful parasitism. G protein-coupled receptors (GPCRs) form the largest superfamily of transmembrane receptors throughout the Eumetazoan phyla, including platyhelminths. Due to their involvement in diverse biological processes, their pharmacological importance, and proven druggability, GPCRs are promising targets for new anthelmintics. However, to identify candidate receptors, a more detailed understanding of the roles of GPCR signalling in schistosome biology is essential. An updated phylogenetic analysis of the S. mansoni GPCR genome (GPCRome) is presented, facilitated by updated genome data that allowed a more precise annotation of GPCRs. Additionally, we review the current knowledge on GPCR signalling in this parasite and provide new insights into the potential roles of GPCRs in schistosome reproduction based on the findings of a recent tissue-specific transcriptomic study in paired and unpaired S. mansoni. According to the current analysis, GPCRs contribute to gonad-specific functions but also to nongonad, pairing-dependent processes. The latter may regulate gonad-unrelated functions during the multifaceted male-female interaction. Finally, we compare the schistosome GPCRome to that of another parasitic trematode, Fasciola, and discuss the importance of GPCRs to basic and applied research. Phylogenetic analyses display GPCR diversity in free-living and parasitic platyhelminths and suggest diverse functions in schistosomes. Although their roles need to be substantiated by functional studies in the future, the data support the selection of GPCR candidates for basic and applied studies, invigorating the exploitation of this important receptor class for drug discovery against schistosomes but also other trematodes.
Topics: Animals; Antiplatyhelmintic Agents; Fasciola; G-Protein-Coupled Receptor Kinases; Gene Expression Profiling; Genome, Helminth; Genomics; Helminth Proteins; Humans; Models, Biological; Organ Specificity; Phylogeny; Protein Kinase Inhibitors; Schistosoma mansoni; Signal Transduction
PubMed: 29346437
DOI: 10.1371/journal.ppat.1006718 -
Archives of Razi Institute Feb 2023Fascioliasis is a common human-animal disease that is reported in most parts of the world. Fascioliasis is also prevalent in different provinces of Iran. Since it has...
Fascioliasis is a common human-animal disease that is reported in most parts of the world. Fascioliasis is also prevalent in different provinces of Iran. Since it has done no study on the excretory/secretory and somatic immunogenic antigens profiles of adult in Iran, the present study was performed on the collected from Mazandaran province. For this purpose, the worm was isolated from the liver of infected sheep, then its excretory/secretory and somatic antigens were prepared from adult worms. The protein of the samples was measured by the Lowry method. Then, somatic and secretory excretions were examined by SDS-PAGE and the protein profile of the two substances was determined. To evaluate the immunogenicity, the somatic and secretory excretions antigens of were injected into white rabbits and after boosting, the blood serum of the rabbits was collected and then Western blotting was performed on them and the results were evaluated. According to the results of Western blotting, 11 somatic antigen bands with a molecular weight of 149, 122, 99, 85, 75, 65, 50, 46, 40, 37, 30 kDa and 12 protein bands of excretory/secretory antigens with molecular weights of 100, 82, 75, 70, 58, 55, 47, 40, 38, 37, 30,25 kDa were observed in adult that immunogenic, which appear to have a protective effect or can be used to prepare a diagnostic kit.
Topics: Animals; Rabbits; Blotting, Western; Electrophoresis, Polyacrylamide Gel; Fasciola; Fascioliasis; Iran; Sheep; Sheep Diseases
PubMed: 37312739
DOI: 10.22092/ARI.2022.359262.2393 -
Annals of Parasitology 2021Fasciolosis is an important food and water-borne parasitic infection caused by the two trematode species, Fasciola hepatica, and F. gigantica. The present study aimed to...
Genetic characterization and phylogenetic analysis of Fasciola species based on ITS2 gene sequence, with first molecular evidence of intermediate Fasciola from water buffaloes in Aswan, Egypt.
Fasciolosis is an important food and water-borne parasitic infection caused by the two trematode species, Fasciola hepatica, and F. gigantica. The present study aimed to identify the phenotypic features and genetic characterization of adult fasciolid that infecting buffaloes were studied in Aswan, Egypt. The genetic identity of Fasciola species was investigated by the analysis of forward and reverse sequences of the ITS-2 of the rDNA gene. The Fasciola isolates were obtained from sheep, buffaloes, and cows in the regions of Aswan. The sequence of ITS2 gene isolates obtained from the present investigation were compared with GenBank reference sequences of F. hepatica, F. gigantica, and intermediate Fasciola. The obtained results were based on morphometric and genetic data which revealed the existence of F. gigantica, F. hepatica, and an intermediate form of Fasciola. Several variable sites were encountered among the investigated isolates in the Aswan, that were compared with the Fasciola species acquiesced in Gene Bank. Furthermore, the relationships between Egyptian Fasciola and Fasciola spp. from various other nations were discussed in the study.
Topics: Animals; Buffaloes; Cattle; Egypt; Fasciola; Fasciola hepatica; Fascioliasis; Phylogeny; Sheep
PubMed: 34021980
DOI: 10.17420/ap6701.312 -
Acta Veterinaria Scandinavica Dec 2021Pasture management influences the prevalence and impact of the pasture parasites (PP) in cattle herds, which cause production-limiting disease worldwide. Evaluating...
BACKGROUND
Pasture management influences the prevalence and impact of the pasture parasites (PP) in cattle herds, which cause production-limiting disease worldwide. Evaluating farmer management strategies is vital when considering sustainable PP control practices. The aim of this questionnaire-based study was to describe the pasture management and control strategies regarding PP in Norwegian beef cattle (BC) and dairy cattle (DC) production systems with a focus on gastrointestinal nematodes (GIN) and Fasciola hepatica.
RESULTS
A total of 745 responses from BC (return rate 20.5%) and 1347 responses from DC farmers (30.7%) were included. The mean total pasture time for DC was 4.2 months for first-season grazers and 4.3 months for second-season grazers and cows, while the corresponding finding in BC was 5.4 months. Home pasture was used for most of the pasture period, particularly for first-season grazer dairy heifers (81%), which were also commonly grazed on the same pasture every year (79%). For most farmers it was necessary for grazing areas to be used for cattle for more than one season (77% of BC farmers and 89% of DC farmers). However, changing the pasture during the season was common in both DC (67%) and BC (70%) herds. The majority of DC farmers (60%) stated that they did not consider that they had a problem with PP. Of the remaining 40%, few respondents could specify whether their herds had a problem due to infection by GIN (11%) or liver flukes (12%). Treatment for GIN was performed by 52% of DC and 34% of BC farmers. Diagnostic faecal samples were collected upon suspicion of parasitic disease by 5% of DC and 16% of BC farmers. Veterinarians were stated as a central source of information about parasite management and treatment.
CONCLUSIONS
Potential risks for exposure to PP were identified, such as use of the same pasture every year for first-season grazers and frequent use of home pasture. The perception of problems related to PP appeared low. Regular anthelmintic treatment without concurrent use of diagnostic faecal samples seems to be common practice.
Topics: Animals; Cattle; Farmers; Fasciola hepatica; Female; Gastrointestinal Tract; Humans; Nematoda; Surveys and Questionnaires
PubMed: 34863233
DOI: 10.1186/s13028-021-00618-7 -
Preventive Veterinary Medicine Jul 2024The common liver fluke, Fasciola hepatica, is a trematode parasite found worldwide, typically with a focal distribution due to its requirement for suitable climatic and...
Estimation of diagnostic sensitivity and specificity of abattoir registrations and bulk tank milk ELISA as herd-level tests for Fasciola hepatica using Bayesian latent class modelling.
The common liver fluke, Fasciola hepatica, is a trematode parasite found worldwide, typically with a focal distribution due to its requirement for suitable climatic and environmental conditions to complete its lifecycle. Bovine fasciolosis causes suboptimal production and economic losses, including liver condemnation at slaughter. The lack of reliable diagnostic methods is a disadvantage to the increasing demand for surveillance and control. The aim of this study was to evaluate the diagnostic accuracy of bulk tank milk (BTM) antibody testing and aggregated abattoir registrations (AAR) of liver fluke as herd-level tests for F. hepatica infection using Bayesian latent class models. Data from the abattoirs in 2019-2021 and BTM, sampled in the winter of 2020/2021, were collected from 437 herds on the southwest coast of Norway. The BTM samples were analysed with the SVANOVIR® F. hepatica-Ab ELISA test, with results given as an optical density ratio (ODR), and later dichotomized using the recommended cut-off value from the test manufacturer (ODR ≥0.3). Based on the BTM ELISA test, 47.8% of the herds tested positive. The AAR test was defined as the herd-level proportion of female slaughtered animals registered with liver fluke infection during the study period. For this test, three cut-offs were used (a proportion of 0.05, 0.1 and 0.2). The herds were split into two subpopulations ("Coastal" and "Inland"), which were expected to differ in true prevalence of F. hepatica infection based on climate-related and geographical factors. The diagnostic accuracies of both tests were estimated using Bayesian latent class models with minimally informative priors. Post-hoc analysis revealed that the maximum sum of sensitivity (Se) and specificity (Sp) of the tests was achieved with a herd-level proportion of ≥0.1 registered with liver fluke as the AAR test. Using this cut-off, the median estimate for the diagnostic accuracy of the BTM ELISA was 90.4% (84.0-96.2 95% Posterior Credible Interval (PCI)) for Se and 95.3% (90.6-100% PCI) for Sp, while the median estimate of Se for AAR was 87.5% (81.4-93.1% PCI) and the median estimate of Sp for AAR was 91.0% (85.2-96.5% PCI). The cut-off evaluation of the SVANOVIR® F. hepatica-Ab ELISA test for BTM confirmed the manufacturer's recommended cut-off of ODR ≥0.3 to denote positive and negative herds. This study suggests that AAR and BTM ELISA test can be used as herd-level tools to monitor liver fluke infection, so that appropriate interventions against infection can be implemented as necessary.
Topics: Animals; Fascioliasis; Cattle; Abattoirs; Enzyme-Linked Immunosorbent Assay; Fasciola hepatica; Bayes Theorem; Cattle Diseases; Sensitivity and Specificity; Milk; Latent Class Analysis; Norway; Female; Prevalence; Antibodies, Helminth
PubMed: 38744092
DOI: 10.1016/j.prevetmed.2024.106213