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1.
Vet Res ; 52(1): 99, 2021 Jul 02.
Artigo em Inglês | MEDLINE | ID: mdl-34215335

RESUMO

The immunomodulatory capacity of F. hepatica antigens is probably one of the main reasons for the development of a driven non-protective Th2 immune response. In this study, we analysed the cellular response of hepatic lymph node cells and CD4+ T cells in terms of proliferative response, efficiency of antigen presentation and cytokine production, to F. hepatica-derived molecules, at early and late stages of the infection. Thirty-one sheep were allocated into five groups and were slaughtered at 16 dpi and 23 wpi. In order to analyse antigen-specific response, the following F. hepatica recombinant molecules were used: rFhCL1, rFhCL2, rFhCL3, rFhCB1, rFhCB2, rFhCB3, rFhStf-1, rFhStf-2, rFhStf-3 and rFhKT1. A cell proliferation assay using hepatic lymph node cells and an antigen presentation cell assay using CD4+ T cells were performed. At 16 dpi, all molecules but rFhStf-2 and rFhKT1 elicited a significant cell proliferative response on hepatic lymph node cells of infected animals. At both early and late stage of the infection, antigen presentation of rFhCB3 and rFhCL2 resulted in higher stimulation index of CD4+ T cells which was IL-2 mediated, although no statistically significant when compared to uninfected animals. Significant cytokine production (IL-4, IL-10 and IFN-γ) was conditioned by the antigen-specific cell stimulation. No CD4+ T cell exhaustion was detected in infected sheep at the chronic stage of the infection. This study addressed antigen-specific response to F. hepatica-derived molecules that are involved in key aspects of the parasite survival within the host.


Assuntos
Antígenos de Helmintos/imunologia , Fasciolíase/veterinária , Linfonodos/imunologia , Doenças dos Ovinos/imunologia , Linfócitos T/imunologia , Animais , Fasciola hepatica/fisiologia , Fasciolíase/imunologia , Fasciolíase/parasitologia , Fígado/imunologia , Masculino , Ovinos , Doenças dos Ovinos/parasitologia , Carneiro Doméstico
2.
Vet Parasitol ; 293: 109427, 2021 May.
Artigo em Inglês | MEDLINE | ID: mdl-33872935

RESUMO

A survey conducted on fallow deer (n = 79) in northern New South Wales Australia, aimed to ascertain the prevalence and gross pathology of liver fluke. In total, three deer populations were assessed (1 farmed and 2 wild) across 2 sites (site A and B) by conducting total fluke counts in the liver and fluke egg counts in faecal samples. At site A, 16 of 19 farmed deer (84.2 %) and 9 of 20 wild deer (45 %) had active or resolved infections. At site B, 16 of 40 wild deer (40 %) had active or resolved infections. Deer with active infections had low fluke burdens (1-11 fluke) which were in the adult development stage, shedding eggs with faeces (0-121.7 eggs per gram). Liver pathology score did not exceed 3.5 out of 5 with gross pathomorphological lesions predominately confined to the peripheral regions of the left lobe. Farmed deer, confined within a fluky habitat, attained the highest group mean pathology score, with dense fibrosis and concomitant atrophy of the left lobe (site A: farmed - 1.8, wild- 0.6; site B: wild - 0.3). Well-defined fibrotic capsules captured and restricted fluke migration beyond the peripheral region of the left lobe of the liver. The presence of live and dead fluke within the fibrotic capsules confirms the inherent ability of fallow deer to resolve infections. This survey has highlighted the susceptibility of fallow deer to liver fluke within an endemic region. Recurrent exposure, as seen in the farmed deer confined within a fluky habitat, appears to strengthen tissue response in terms of gross pathology and may impede the release of fluke eggs from the liver. Low fluke burdens and limited lesions suggest fallow deer have a strong level of resistance to liver fluke. Nevertheless, within this endemic region, fallow deer are widespread and clearly facilitating the liver fluke life cycle. Further research is warranted to ascertain the impact of fallow deer on disease transmission in livestock production when cohabiting the grazing environment.


Assuntos
Cervos , Fasciola hepatica , Fasciolíase , Animais , Cervos/parasitologia , Fasciola hepatica/fisiologia , Fasciolíase/epidemiologia , Fasciolíase/patologia , Fezes , New South Wales/epidemiologia , Óvulo , Prevalência
3.
Sci Rep ; 11(1): 6712, 2021 03 24.
Artigo em Inglês | MEDLINE | ID: mdl-33762636

RESUMO

Fasciola hepatica, a global worm parasite of humans and their livestock, regulates host innate immune responses within hours of infection. Host macrophages, essential to the first-line defence mechanisms, are quickly restricted in their ability to initiate a classic protective pro-inflammatory immune response. We found that macrophages from infected animals are enriched with parasite-derived micro(mi)RNAs. The most abundant of these miRNAs, fhe-miR-125b, is released by the parasite via exosomes and is homologous to a mammalian miRNA, hsa-miR-125b, that is known to regulate the activation of pro-inflammatory M1 macrophages. We show that the parasite fhe-miR-125b loads onto the mammalian Argonaut protein (Ago-2) within macrophages during infection and, therefore, propose that it mimics host miR-125b to negatively regulate the production of inflammatory cytokines. The hijacking of the miRNA machinery controlling innate cell function could be a fundamental mechanism by which worm parasites disarm the early immune responses of their host to ensure successful infection.


Assuntos
Fasciola hepatica/fisiologia , Fasciolíase/etiologia , Interações Hospedeiro-Parasita , Imunidade Inata , Macrófagos/imunologia , Macrófagos/parasitologia , MicroRNAs/genética , Animais , Suscetibilidade a Doenças/imunologia , Fasciolíase/metabolismo , Regulação da Expressão Gênica , Interações Hospedeiro-Parasita/genética , Interações Hospedeiro-Parasita/imunologia , Macrófagos/metabolismo , MicroRNAs/química , Interferência de RNA , Transdução de Sinais
4.
J Immunol ; 206(7): 1618-1630, 2021 04 01.
Artigo em Inglês | MEDLINE | ID: mdl-33579723

RESUMO

Certain proinflammatory stimuli can metabolically and epigenetically modify monocytes/macrophages or NK cells to be more responsive to secondary stimuli, a process known as trained innate immunity. However, the longevity of trained innate immunity is unclear. In this study, we report that Fasciola hepatica excretory-secretory products (FHES) can imprint an anti-inflammatory phenotype on long-term hematopoietic stem cells (HSCs) and monocyte precursor populations, enhancing their proliferation and differentiation into anti-inflammatory Ly6Clow monocytes. These monocytes expand and populate multiple compartments within mice, conferring hyporesponsiveness to proinflammatory stimuli and reduced susceptibility to induction of experimental autoimmune encephalomyelitis. Mice treated with FHES had enhanced alternatively activated macrophages, reduced Th1 and Th17 responses, and attenuating effects on autoimmunity that persisted for 8 mo. Furthermore, transplantation of HSCs from FHES-treated mice transferred the anti-inflammatory phenotype to naive mice. Our findings demonstrate that helminth products can modulate HSCs to promote development of anti-inflammatory myeloid cells that attenuate T cell-mediated autoimmune disease.


Assuntos
Encefalomielite Autoimune Experimental/imunologia , Fasciola hepatica/fisiologia , Células-Tronco Hematopoéticas/fisiologia , Inflamação/imunologia , Células Matadoras Naturais/imunologia , Macrófagos/fisiologia , Monócitos/fisiologia , Esclerose Múltipla/imunologia , Células Th1/imunologia , Células Th17/imunologia , Animais , Antígenos Ly/metabolismo , Autoimunidade , Diferenciação Celular , Proliferação de Células , Células Cultivadas , Modelos Animais de Doenças , Humanos , Ativação de Macrófagos , Camundongos
5.
Dev Comp Immunol ; 114: 103787, 2021 01.
Artigo em Inglês | MEDLINE | ID: mdl-32791176

RESUMO

Fasciola hepatica is the causative agent of fasciolosis, a worldwide distributed zoonotic disease, leading to hepatitis in humans and livestock. Newly excysted juveniles (NEJ) of F. hepatica are the first invasive stages to encounter leukocytes of host innate immune system in vivo. Among leukocytes, polymorphonuclear neutrophils (PMN) are the most abundant granulocytes of blood system and first ones to migrate into infection sites. PMN are able to cast neutrophil extracellular traps (NETs), also known as NETosis, consisting of nuclear DNA, decorated with histones, enzymes and antimicrobial peptides, which can entrap and eventually kill invasive parasites. Given that only few large parasitic helminths have been identified as potent NETosis inducers, here we studied for first time whether different F. hepatica stages can also trigger NETosis. Therefore, isolated bovine PMN were co-cultured with viable F. hepatica-NEJ, -metacercariae, -eggs and soluble antigen (FhAg). Interestingly, all stages failed to induce considerable levels of NETosis as detected by immunofluorescence- and scanning electron microscopy (SEM) analyses. NEJ remained motile until the end of incubation period. In line, NETosis quantification via nuclear area expansion (NAE) analysis revealed NEJ as weak NETosis inducers. However, bovine PMN frequently displaced towards motile NEJ and were found attached to NEJ surfaces. Functional PMN chemotaxis assays using vital F. hepatica-NEJ revealed a slight increase of PMN migration when compared to non-exposed controls. Additional experiments on intra- and extracellular reactive oxygen species (ROS) production revealed that soluble FhAg failed to induce ROS production of exposed PMN. Finally, mitochondrial oxygen consumption rates (OCR), extracellular acidification rates (ERAC) and proton production rates (PPR) were not significantly increased in FhAg-stimulated PMN. In summary, data suggest that F. hepatica might effectively evade PMN activation and NETosis by secreting parasite-specific molecules to either resolve NETs or to impair NETosis signaling pathways. We call for future molecular analysis not only on F. hepatica-derived NETosis modulation but also on its possible role in fasciolosis-associated pathology in vivo.


Assuntos
Armadilhas Extracelulares/metabolismo , Fasciola hepatica/fisiologia , Fasciolíase/imunologia , Hepatite/imunologia , Mitocôndrias/metabolismo , Neutrófilos/imunologia , Animais , Bovinos , Respiração Celular , Interações Hospedeiro-Parasita , Humanos , Evasão da Resposta Imune , Imunidade Inata , Espécies Reativas de Oxigênio/metabolismo , Zoonoses
6.
Anal Chem ; 92(23): 15361-15369, 2020 12 01.
Artigo em Inglês | MEDLINE | ID: mdl-33170647

RESUMO

Cholangiocarcinoma (CCA) is a bile duct cancer that originates in the bile duct epithelium. Northeastern Thailand has the highest incidence of CCA, and there is a direct correlation with liver fluke (Opisthorchis viverrini) infection. The high mortality rate of CCA is a consequence of delayed diagnosis. Fourier transform infrared (FTIR) spectroscopy is a powerful technique that detects the absorbance of molecular vibrations and is perfectly suited for the interrogation of biological samples. In this study, we applied synchrotron radiation-FTIR (SR-FTIR) microspectroscopy and focal plane array (FPA-FTIR) microspectroscopy to characterize periductal fibrosis and bile duct cells progressing to CCA induced by inoculating O. viverrini metacercariae into hamsters. SR-FTIR and FPA-FTIR measurements were performed in liver sections harvested from 1-, 2-, 3-, and 6-month post-infected hamsters compared to uninfected liver tissues. Principal component analysis (PCA) of the tissue samples showed a clear discrimination among uninfected and early-stage (1 and 2 months) and cancerous-stage (3 and 6 months) tissues. The discrimination is based on intensity changes in the phosphodiester band (1081 cm-1), amino acid residue (∼1396 cm-1), and C═O stretching carboxylic esters (1745 cm-1). Infected tissues also show definitive bands at ∼1280, 1234, and 1201 cm-1 characteristic of the collagen triplet and indicative of fibrosis. Hierarchical cluster analysis (HCA) was performed on the FPA data and showed a classification into specific cell types. Hepatocyte, fibrotic lesion, and bile duct (cancer) were classified and HCA mapping showed similar cellular distribution pattern compared to Sirius red staining. This study was also extended to less invasive sample analysis using attenuated total reflectance-FTIR (ATR-FTIR) spectroscopy. Sera from O. viverrini-infected and uninfected hamsters were analyzed using multivariate analysis, including principal component analysis (PCA), and partial least squares-discriminant analysis (PLS-DA). PCA was able to classify spectra of normal, early-stage CCA, and CCA, while the PLS-DA gave 100% accuracy for the validation. The model was established from 17 samples (11 normal, 6 cancer) in the calibration set and 9 samples in the validation set (4 normal, 2 cancer, 3 precancerous). These results indicate that FTIR-based technology is a potential tool to detect the progression of CCA, especially in the early stages of the disease.


Assuntos
Neoplasias dos Ductos Biliares/diagnóstico por imagem , Colangiocarcinoma/diagnóstico por imagem , Progressão da Doença , Fasciola hepatica/fisiologia , Imagem Óptica/instrumentação , Espectroscopia de Infravermelho com Transformada de Fourier/instrumentação , Síncrotrons , Animais , Neoplasias dos Ductos Biliares/etiologia , Neoplasias dos Ductos Biliares/patologia , Colangiocarcinoma/etiologia , Colangiocarcinoma/patologia , Cricetinae , Modelos Animais de Doenças
7.
Parasit Vectors ; 13(1): 496, 2020 Sep 30.
Artigo em Inglês | MEDLINE | ID: mdl-32998778

RESUMO

BACKGROUND: Fascioliasis caused by the trematodes Fasciola hepatica and F. gigantica, is a global neglected zoonotic disease estimated to cost the livestock industry over €2.5 billion annually. Farm management measures and sustainable use of anthelmintics can, in principle, effectively control trematode infection in livestock and reduce the rate of developing anthelmintic resistance. Previously, we designed an environmental DNA (eDNA) assay to identify a common trematode intermediate host, the freshwater snail Galba truncatula, in water sources to measure specific trematode infection risk areas on pasture-land. To improve this procedure, we now report a loop-mediated isothermal amplification (LAMP) assay to identify G. truncatula eDNA. METHODS: A LAMP assay was designed and optimised (e.g. temperature, time duration and primer concentration) to identify G. truncatula DNA. The ability of the LAMP assay to target G. truncatula DNA was identified, and LAMP assay limit of detection was investigated in comparison to conventional PCR. In the field, 48 water samples were collected from stream, ditch and water pool habitats in four locations at two Aberystwyth University farms over a seven week period to investigate the applicability of the LAMP assay for use on eDNA samples, in comparison to conventional PCR. RESULTS: The LAMP assay delivered detectable results in 30 min at 63 °C. The assay discriminated between G. truncatula DNA and non-target DNA, presenting a level of DNA detection comparable to conventional PCR. No significant difference was found between the ability of the LAMP and PCR assay to identify G. truncatula eDNA in water samples. Kappa coefficient analysis revealed a moderate level of agreement between LAMP and PCR assays. CONCLUSIONS: This study demonstrated that the LAMP assay can detect G. truncatula eDNA in a simple and rapid manner. The LAMP assay may become a valuable tool to determine optimum pasture management for trematode parasite control.


Assuntos
/genética , Fasciolíase/veterinária , Água Doce/parasitologia , Técnicas de Diagnóstico Molecular/métodos , Técnicas de Amplificação de Ácido Nucleico/métodos , Caramujos/genética , Animais , Ecossistema , Fasciola hepatica/genética , Fasciola hepatica/fisiologia , Fasciolíase/parasitologia , Fasciolíase/prevenção & controle , Fasciolíase/transmissão , Gado/parasitologia , Caramujos/parasitologia
8.
Front Immunol ; 11: 579801, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33042162

RESUMO

Eosinophils are granulocytes that participate in the defense against helminth parasites and in hypersensitivity reactions. More recently, eosinophils were shown to have other immunomodulatory functions, such as tissue reparation, metabolism regulation, and suppression of Th1 and Th17 immune responses. In the context of parasitic helminth infections, eosinophils have a controversial role, as they can be beneficial or detrimental for the host. In this work, we investigate the role of eosinophils in an experimental infection in mice with the trematode parasite Fasciola hepatica, which causes substantial economical losses around the world due to the infection of livestock. We demonstrate that eosinophils are recruited to the peritoneal cavity and liver from F. hepatica-infected mice and this recruitment is associated with increased levels of CCL11, TSLP, and IL-5. Moreover, the characterization of peritoneal and hepatic eosinophils from F. hepatica-infected mice showed that they express distinctive molecules of activation and cell migration. Depletion of eosinophils with an anti-Siglec-F antibody provoked more severe clinical signs and increased liver damage than control animals which were accompanied by an increase in the production of IL-10 by hepatic and splenic CD4+ T cells. In addition, we also report that eosinophils participate in the modulation of humoral immune responses during F. hepatica infection, contributing to their degranulation. In conclusion, we demonstrate that eosinophils are beneficial for the host during F. hepatica infection, by limiting the production of IL-10 by specific CD4+ T cells and favoring eosinophil degranulation induced by specific antibodies. This work contributes to a better understanding of the role of eosinophils in parasitic helminth infections.


Assuntos
Linfócitos T CD4-Positivos/imunologia , Eosinófilos/imunologia , Fasciola hepatica/fisiologia , Fasciolíase/imunologia , Fígado/patologia , Animais , Citotoxicidade Celular Dependente de Anticorpos , Degranulação Celular , Células Cultivadas , Quimiocina CCL11/metabolismo , Modelos Animais de Doenças , Feminino , Interações Hospedeiro-Patógeno , Humanos , Imunomodulação , Interleucina-10/metabolismo , Camundongos , Camundongos Endogâmicos BALB C , Ovinos , Lectinas Semelhantes a Imunoglobulina de Ligação ao Ácido Siálico/imunologia
9.
Vet Parasitol ; 285: 109218, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32841785

RESUMO

The parasitic liver fluke, Fasciola hepatica, has a detrimental impact on food security and poses a welfare concern to ruminant livestock. F. hepatica metacercariae, shed from an intermediate mud snail host, encyst on vegetation and present a source of infection to grazing livestock. Feeding grass silage to ruminants is a common practice, however the role it plays in the transmission of F. hepatica remains largely unknown. Our current understanding relies on historical studies that are not representative of current silage production and did not apply molecular methods to detect F. hepatica DNA persistence within silages. This study determined the impact of specific fermentation factors, including grass dry matter (DM) content (20, 30 & 40 %), length of ensiling period and maintaining an anaerobic environment on F. hepatica metacercariae viability. In vitro excystment assays demonstrated that regardless of grass DM content, metacercariae ensiled under anaerobic conditions were not viable from two weeks post-sealing. Metacercariae recovered from ensiled grass of 20 % DM content subjected to aerobic spoilage, remained viable for up to 10 weeks. DNA of F. hepatica remained detectable for up to 10 weeks in both anaerobic and spoiled silages. This study highlights i) the importance of maintaining an anaerobic ensiling environment to eliminate the risk of F. hepatica transmission from silage and ii) an inverse relationship between grass DM content and duration of metacercariae survival within spoiled silages. Improving our understanding of trematode metacercariae survival rates within silages, especially of highly pathogenic species such as F. hepatica, allows farmers to make informed decisions regarding on-farm parasite control.


Assuntos
Fasciola hepatica/fisiologia , Fasciolíase/veterinária , Fermentação , Metacercárias/fisiologia , Poaceae/metabolismo , Poaceae/parasitologia , Silagem/parasitologia , Anaerobiose , Animais , Fasciolíase/prevenção & controle
10.
Prev Vet Med ; 182: 105103, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32750638

RESUMO

We report a European wide assessment of the economic burden of gastrointestinal nematodes, Fasciola hepatica (common liver fluke) and Dictyocaulus viviparus (bovine lungworm) infections to the ruminant livestock industry. The economic impact of these parasitic helminth infections was estimated by a deterministic spreadsheet model as a function of the proportion of the ruminant population exposed to grazing, the infection frequency and intensity, the effect of the infection on animal productivity and mortality and anthelmintic treatment costs. In addition, we estimated the costs of anthelmintic resistant nematode infections and collected information on public research budgets addressing helminth infections in ruminant livestock. The epidemiologic and economic input data were collected from international databases and via expert opinion of the Working Group members of the European Co-operation in Science and Technology (COST) action COMbatting Anthelmintic Resistance in ruminants (COMBAR). In order to reflect the effects of uncertainty in the input data, low and high cost estimates were obtained by varying uncertain input data arbitrarily in both directions by 20 %. The combined annual cost [low estimate-high estimate] of the three helminth infections in 18 participating countries was estimated at € 1.8 billion [€ 1.0-2.7 billion]. Eighty-one percent of this cost was due to lost production and 19 % was attributed to treatment costs. The cost of gastrointestinal nematode infections with resistance against macrocyclic lactones was estimated to be € 38 million [€ 11-87 million] annually. The annual estimated costs of helminth infections per sector were € 941 million [€ 488 - 1442 million] in dairy cattle, € 423 million [€ 205-663 million] in beef cattle, € 151million [€ 90-213 million] in dairy sheep, € 206 million [€ 132-248 million] in meat sheep and € 86 million [€ 67-107 million] in dairy goats. Important data gaps were present in all phases of the calculations which lead to large uncertainties around the estimates. Accessibility of more granular animal population datasets at EU level, deeper knowledge of the effects of infection on production, levels of infection and livestock grazing exposure across Europe would make the largest contribution to improved burden assessments. The known current public investment in research on helminth control was 0.15 % of the estimated annual costs for the considered parasitic diseases. Our data suggest that the costs of enzootic helminth infections which usually occur at high prevalence annually in ruminants, are similar or higher than reported costs of epizootic diseases. Our data can support decision making in research and policy to mitigate the negative impacts of helminth infections and anthelmintic resistance in Europe, and provide a baseline against which to measure future changes.


Assuntos
Doenças dos Bovinos/economia , Efeitos Psicossociais da Doença , Infecções por Dictyocaulus/economia , Fasciolíase/veterinária , Doenças das Cabras/economia , Doenças dos Ovinos/economia , Animais , Bovinos , Dictyocaulus/fisiologia , Europa (Continente) , Fasciola hepatica/fisiologia , Fasciolíase/economia , Cabras , Ovinos , Carneiro Doméstico
11.
Rev Bras Parasitol Vet ; 29(2): e019019, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32609241

RESUMO

The aim of this research was to assess the copro-prevalence of Fasciola hepatica in owned Chilean breed horses (Equus caballus) residing in the province of Concepción, Chile. The study was carried out throughout October 2017. Samples were taken from all (100%) Chilean breed horse (124 specimens; 45 females and 79 males, aged between 7 months and 24 years old) from the Concepción province. A rectal stool sample was obtained from each animal. This was analyzed using the Army Medical School method (AMS III) technique to detect F. hepatica eggs. Information about the horse's age, sex, previous fasciolicide application, and an assessment of body condition was also obtained. Fisher tests were carried out to analyze the results. Ten horses (8.06%) were positive for the presence of F. hepatica eggs. No significant difference of copro-prevalence was found between age (young 8.47%, old 7.69%), sex (female 11.1%, male 6.33%), the previous application of fasciolicide (dewormed 10%, not dewormed 7.89%), or body condition (low condition 11.1%, high condition 0.7%) categories (Fisher tests: P>0.05 in all cases). The results of this study suggest that Chilean breed horses constitute part of the reservoir of F. hepatica for both ruminant populations and humans in the Concepción province.


Assuntos
Fasciola hepatica , Fasciolíase , Fezes , Doenças dos Cavalos , Animais , Chile/epidemiologia , Fasciola hepatica/fisiologia , Fasciolíase/epidemiologia , Fasciolíase/veterinária , Fezes/parasitologia , Feminino , Doenças dos Cavalos/epidemiologia , Doenças dos Cavalos/parasitologia , Cavalos , Humanos , Masculino , Prevalência
12.
Vet Res ; 51(1): 76, 2020 Jun 05.
Artigo em Inglês | MEDLINE | ID: mdl-32503674

RESUMO

Polyparasitism occurs when animals harbour multiple parasites concomitantly. It is a common occurrence but is generally understudied in wild and domestic animals. Fasciola hepatica and Echinococcus granulosus, which are helminths of ungulates, frequently coinfect cattle. The effects of this particular type of polyparasitism are not well documented. The metacestode of Echinococcus granulosus is surrounded by the adventitial layer, which constitutes the host immune response to the parasite. This layer in cattle is produced by a granulomatous reaction and is involved in echinococcal cyst (EC) fertility. Due to the systemic immune-modulating abilities of Fasciola hepatica, coinfection possibly generates a favourable environment for EC growth. A total of 203 Echinococcus granulosus sensu stricto cysts were found in 82 cattle, of which 42 ECs were found in 31 animals coinfected with Fasciola hepatica. The overall infection intensity was 3 cysts per animal. Coinfection with Fasciola hepatica decreased the mean infection intensity to 1.4 cysts per animal. Regarding EC size, coinfection resulted in smaller ECs (15.91 vs 22.09 mm), especially for infertile lung cysts. The adventitial layer of ECs in coinfected animals lacked lymphoid follicles and palisading macrophages, which are generally hallmarks of the granulomatous immune response. The ECs in coinfected animals had organized laminated layers, whereas those in animals without coinfection did not. Although coinfection was not statistically associated with EC fertility, we did not find fertile cysts in the livers of coinfected animals. We concluded that coinfection with Fasciola hepatica and Echinococcus granulosus has a detrimental effect on ECs, particularly infertile cysts.


Assuntos
Doenças dos Bovinos/parasitologia , Coinfecção/veterinária , Equinococose Hepática/veterinária , Equinococose Pulmonar/veterinária , Echinococcus granulosus/fisiologia , Fasciola hepatica/fisiologia , Fasciolíase/veterinária , Animais , Bovinos , Doenças dos Bovinos/imunologia , Doenças dos Bovinos/patologia , Coinfecção/imunologia , Coinfecção/patologia , Cistos/parasitologia , Cistos/patologia , Cistos/veterinária , Equinococose Hepática/imunologia , Equinococose Hepática/parasitologia , Equinococose Hepática/patologia , Equinococose Pulmonar/imunologia , Equinococose Pulmonar/parasitologia , Equinococose Pulmonar/patologia , Fasciolíase/imunologia , Fasciolíase/parasitologia , Fasciolíase/patologia
14.
Vet Parasitol ; 281: 109094, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-32344146

RESUMO

Fasciola hepatica is a common parasite of livestock in Ireland, causing significant economic losses and affecting animal welfare. A previous abattoir study of 200 horses led to an estimated 9.5 % prevalence of infection in horses slaughtered in Ireland. However, the epidemiology and pathogenic significance of this infection in this species is not well-described. The objectives of this study were to determine the susceptibility of horses to oral challenge infection with F. hepatica metacercariae, and to document the course of the infection along with serological and biochemical response. We attempted an experimental infection of horses (n = 10; 9 geldings and 1 mare) with F. hepatica. Four were given 1000 metacercariae, four 500 metacercariae and two were sham-infected. Blood and faecal samples were taken at intervals up to 18 weeks post-infection (wpi). ELISA assays were used to assess sero-conversion in the experimental horses and also in a panel of sera from horses of known fluke status. No flukes were recovered from any of the livers, and neither were any lesions that could be attributed to F. hepatica infection observed. Coproantigen ELISA was negative throughout for all horses. Three antibody detection ELISAs, useful in diagnosing fasciolosis in other species, had limitations as diagnostic aids as determined using a panel of sera from horses of known F. hepatica infection status. This study is limited by the relatively small number of animals included, and the relatively short duration of the study period. Failure to establish infection after oral challenge raises fundamental questions on the pathophysiology and epidemiology of equine fasciolosis.


Assuntos
Suscetibilidade a Doenças/veterinária , Fasciola hepatica/fisiologia , Fasciolíase/veterinária , Doenças dos Cavalos/parasitologia , Animais , Suscetibilidade a Doenças/parasitologia , Fasciolíase/parasitologia , Cavalos
15.
Vet Res ; 51(1): 33, 2020 Mar 04.
Artigo em Inglês | MEDLINE | ID: mdl-32131896

RESUMO

Fasciola hepatica has been shown to have a high capacity for immunomodulation of the host response, making the development of protective vaccines extremely difficult. One of these immunomodulation mechanisms is the impairment of dendritic cells (DC) maturation and, therefore, suppression of antigenic presentation. The aim of this study was to evaluate the pathological changes as well as the characterization of two antigen presenting cells, DC (CD1b, CD83 and MHC-II positive) and follicular dendritic cells (FDC) (CNA.42, S100 and CD83 positive) by immunohistochemistry in the hepatic lymph nodes (HLN) and livers of sheep during the early stages of infection with F. hepatica [9 and 18 days post-infection (dpi)], compared with an uninfected group (UC) as a control. The results revealed a marked hyperplasia of HLN germinal centres at 9 and, in particular, 18 dpi, with respect to the UC group, with coincidental increased expression of CNA.42 in FDC of lymphoid follicles and CD1b in the DC of paracortical areas at 18 dpi. However, the expression of MHC-II and CD83 decreased at 9 and, particularly, at 18 dpi in HLN compared with that in the UC group. Since both markers are related to active presentation of antigens by DC and FDC, the results of the present study suggest that, despite the marked hyperplasia of HLN and increase in DC and FDC numbers during early stages of infection, the DC and FDC antigenic presentation capacity, as suggested by the expression of the markers MHC-II and CD83, is suppressed by the parasite. This suppression was not observed in the liver, probably because of the low number of DC. This is the first study of the immunophenotype of DCs and FDC in sheep infected with F. hepatica.


Assuntos
Células Dendríticas Foliculares/patologia , Células Dendríticas/patologia , Fasciolíase/veterinária , Fígado/patologia , Linfonodos/patologia , Doenças dos Ovinos/patologia , Animais , Fasciola hepatica/fisiologia , Fasciolíase/patologia , Marcadores Genéticos , Ovinos
16.
Parasite ; 27: 17, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32186511

RESUMO

Field investigations in 14 wild watercress beds located in the French region of Limousin, a known endemic area for distomatosis, were performed for three years to determine the distance that cercariae of Fasciola hepatica can reach in water before their encystment on the host plant. Each bed was located on the course of an open drainage furrow, while snails (Galba truncatula) lived upstream around the emergence of a source. Five plant species were collected in early April and examined to find metacercariae. Most cysts were noted on Nasturtium officinale (188 on 48.7 kg of dripped plants), followed by Helosciadium nodiflorum (125 on 33.4 kg). On the other plant species, there were few larvae. Most cercariae encysted on the plants growing in the most upstream part of each bed, usually on the first 50 cm in length. When water in the beds was fast running, the distribution of metacercariae was more limited and their number was fewer than those in the beds fed by a slow flow of water. Cercariae were able to swim or were carried away by the current up to a mean of 5 m in slow-flow waters before encysting; this distance was only 4 m in faster waters. Plants growing on the most upstream section of a watercress bed located in a drainage furrow are the most used by cercariae for their encystment, when snails live around the emergence of a source. The speed of the water current affected the number and distribution of metacercariae in the bed.


TITLE: Fasciola hepatica : la dispersion des cercaires émises par le mollusque Galba truncatula. ABSTRACT: Des investigations de terrain dans 14 cressonnières naturelles localisées dans la région française du Limousin, zone connue d'endémie de distomatose, ont été effectuées pendant trois années pour déterminer la distance que les cercaires de Fasciola hepatica peuvent atteindre dans l'eau avant leur enkystement sur la plante hôte. Chaque cressonnière était située sur le cours d'une rigole de drainage superficiel, tandis que les mollusques (Galba truncatula) vivaient plus en amont autour de l'émergence d'une source. Cinq espèces végétales ont été recueillies au début d'avril et examinées pour y trouver des métacercaires. La plupart des kystes ont été observés sur Nasturtium officinale (188 sur 48,7 kg de plantes égouttées), suivis par Helosciadium nodiflorum (125 sur 33,4 kg). Sur les autres espèces végétales, il y avait peu de larves. La plupart des cercaires étaient enkystées sur les plantes qui poussaient dans la partie la plus en amont de chaque cressonnière (habituellement sur les premiers 50 cm de longueur). Lorsque l'eau courante dans les cressonnières était rapide, la distribution des métacercaires était plus limitée et leur nombre était inférieur à celui observé dans les stations alimentées par un débit d'eau lent. Les cercaires ont été capables de nager ou ont été entrainées par le courant jusqu'à 5 m en moyenne dans une eau à écoulement lent avant leur enkystement ; cette distance n'était que de 4 m dans les eaux plus rapides. Les plantes qui poussent sur la section la plus en amont d'une cressonnière située dans une rigole de drainage sont les plus utilisées par les cercaires pour leur enkystement lorsque les mollusques vivent autour de l'émergence d'une source. La vitesse du courant d'eau affecte le nombre et la distribution des métacercaires dans la cressonnière.


Assuntos
Cercárias/fisiologia , Vetores de Doenças , Fasciola hepatica/fisiologia , Caramujos/parasitologia , Animais , Larva , Metacercárias , Nasturtium/parasitologia , Plantas/parasitologia
17.
Vet Parasitol Reg Stud Reports ; 19: 100359, 2020 01.
Artigo em Inglês | MEDLINE | ID: mdl-32057386

RESUMO

Fasciolosis is a zoonotic disease caused by Fasciola hepatica and Fasciola gigantica. Over the last decade, diagnostic tools to detect and differentiate Fasciola species have improved, but our knowledge of the distribution of haplotypes and gene flow of this parasite is not comprehensive yet. The purpose of this study was to investigate this gap in the epidemiology of F. hepatica in different provinces of Iran between 2015 and 2017. Isolated Fasciola were collected from abattoirs in 9 provinces. The partial sequence of mitochondrial NADH dehydrogenase subunit 1 (ND1) gene was used for the identification and molecular analysis of F. hepatica isolates. The amplified PCR products were purified and subjected to direct sequencing for subsequent construction of phylogenetic tree and network analysis. In the 130 subjects analyzed, 37 ND1 haplotypes were detected. This is the first study in Iran which investigates F. hepatica population and its genetic structure, based on mitochondrial ND1 marker in different geographical regions of Iran.


Assuntos
Doenças dos Bovinos/parasitologia , Fasciola hepatica/fisiologia , Fasciolíase/veterinária , Variação Genética , Doenças das Cabras/parasitologia , Proteínas de Helminto/genética , NADH Desidrogenase/genética , Doenças dos Ovinos/parasitologia , Animais , Bovinos , Fasciola hepatica/genética , Fasciolíase/parasitologia , Cabras , Haplótipos , Irã (Geográfico) , Ovinos , Carneiro Doméstico
18.
Vet Parasitol Reg Stud Reports ; 19: 100364, 2020 01.
Artigo em Inglês | MEDLINE | ID: mdl-32057392

RESUMO

Fasciola hepatica is a parasitic trematode of worldwide distribution, which affects cattle and a large number of mammals, including man. An investigation was carried out to the Colombian Northeastern Mountain between October 2017 and February 2018 with the aim to determine the prevalence and risk factors associated with Fasciola hepatica. Thirty-four farms whose owners agreed to participate in the study were included. Overall, 103 bovines and 97 sheep were examined. A fecal and blood sample was collected from each animal, and all the samples were identified and stored in a refrigerated box to be transported to the Parasitology laboratory for analysis. Fecal samples were processed with a coprological technique, and blood by ELISA test. A written epidemiological survey was applied on all farms. The results indicate 20.5% of coprological prevalence and 41.5% of seroprevalence (SP). Evidence of the parasite was demonstrated in the three municipalities; however, statistical differences were found (P < .05), with higher seropositivity in Duitama municipality (SP = 83.3%). Regarding risk factor, pure breeds of cattle showed 2.5 (SP = 56.1, OR = 2.5) times higher of infection than crossed breed. Cattle and sheep from 12 to 24 months of age, showed 2.5 (SP = 66.7%, OR = 2.5) and 5.9 times (SP = 44.2%, OR = 5.9), respectively, increased infection risk. The presence of snails on the farms had higher odds for testing F. hepatica-positive, therefore, showed to be an important risk factor. The presence of antibodies against F. hepatica in cattle and sheep from the region under study suggests it is endemic and should be controlled by control and prevention programs in the farms.


Assuntos
Doenças dos Bovinos/epidemiologia , Fasciola hepatica/fisiologia , Fasciolíase/veterinária , Doenças dos Ovinos/epidemiologia , Animais , Bovinos , Doenças dos Bovinos/parasitologia , Colômbia/epidemiologia , Fasciolíase/epidemiologia , Fasciolíase/parasitologia , Prevalência , Fatores de Risco , Ovinos , Doenças dos Ovinos/parasitologia , Carneiro Doméstico
19.
Vet Parasitol ; 278: 109028, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31986420

RESUMO

Fasciola hepatica is the causative agent of fasciolosis, a parasitic zoonosis of global distribution causing significant economic losses in animal production and a human public health problem in low-income countries. Hosts are infected by ingestion of aquatic plants carrying metacercariae. Once ingested, the juvenile parasites excyst in the small intestine and, after crossing it, they follow a complex migratory route that lead the parasites to their definitive location in the bile ducts. Despite being a critical event in the progression of the infection, the available data on the cross-talk relationships between the parasite and the host at an early stage of the infection are scarce. The objective of the present work is to characterize the proteomic changes occurring in both the parasite and the host, through the development of a novel in vitro model, to shed light on the molecular pathways of communication between the newly excysted juveniles (NEJ) from F. hepatica and the host's intestinal epithelium. For this, in vitro excystation of F. hepatica metacercariae was carried out and NEJ were obtained. Additionally, optimal conditions of growth and expansion of mouse primary small intestinal epithelial cells (MPSIEC) in culture were fine-tuned. Tegumentary and somatic parasite antigens (NEJ-Teg and NEJ-Som), as well as host cell protein lysate (MPSIEC-Lys) were obtained before and after 24 h co-culture of NEJ with MPSIEC. We used an isobaric tags for relative and absolute quantitation (iTRAQ)-based strategy to detect 191 and 62 up-regulated, and 112 and 57 down-regulated proteins in the NEJ-Teg and NEJ-Som extracts, respectively. Similarly, 87 up-regulated and 73 down-regulated proteins in the MPSIEC-Lys extract were identified. Taking into account the biological processes in which these proteins were involved, interesting mechanisms related to parasite development, invasion and evasion, as well as manipulation of the host intestinal epithelial cell adhesion, immunity and apoptosis pathways, among others, could be inferred, taking place at the host-parasite interface. The further understanding of these processes could constitute promising therapeutic targets in the future against fasciolosis.


Assuntos
Fasciola hepatica/fisiologia , Interações Hospedeiro-Parasita , Técnicas In Vitro/veterinária , Mucosa Intestinal/parasitologia , Intestino Delgado/parasitologia , Animais , Células Epiteliais/parasitologia , Fasciola hepatica/crescimento & desenvolvimento , Técnicas In Vitro/métodos , Camundongos , Camundongos Endogâmicos C57BL
20.
Microb Pathog ; 139: 103909, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31805319

RESUMO

Liver flukes of animals are parasitic flatworms of major socioeconomic importance in many countries. Particularly, Fasciola gigantica is a leading cause of production losses to the livestock (mainly sheep and cattle) and meat industries due to clinical disease, reduced weight gain and milk production, and deaths. Immune responses induced by helminth have been extensively studied, but there is limited information on this aspect by F. gigantica, especially on macrophages induced with this parasite. Studies have shown that host immune responses induced by parasitic infection is greatly correlated with the macrophage polarization axis. In the present study, we used the murine model of F. gigantica to explore the interaction of host and F. gigantica. We found F. gigantica NEJs promoted pathology and fibrosis of mice liver, and the enlargement of mice spleen. We also showed that macrophages were recruited to mice peritoneal cavity at 5 days post infection. By evaluating the expression of genetic markers of M2 macrophages such as Arg-1, Ym1 and RELMɑ, and genetic marker of M1 macrophages iNOS, we showed that M2 macrophages were induced by F. gigantica. M2 macrophages are central to the immune response during helminth infection, and our findings in this study provided insight into the immune interaction between F. gigantica and host.


Assuntos
Fasciola hepatica/fisiologia , Fasciola/fisiologia , Fasciolíase/parasitologia , Cirrose Hepática/parasitologia , Macrófagos/parasitologia , Animais , Fasciola/genética , Fasciola/crescimento & desenvolvimento , Fasciola hepatica/crescimento & desenvolvimento , Fasciolíase/imunologia , Fasciolíase/patologia , Feminino , Humanos , Cirrose Hepática/imunologia , Cirrose Hepática/patologia , Macrófagos/imunologia , Masculino , Camundongos , Fenótipo
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