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Sample records for leishmania neospora plasmodium

  1. Kennel dogs as sentinels of Leishmania infantum, Toxoplasma gondii and Neospora caninum in Majorca Island, Spain

    Science.gov (United States)

    Kennel dogs can serve as sentinels and/or reservoirs of diseases of veterinary and zoonotic interest because they have often roamed free and lived outdoors, being exposed to pathogens. We tested for evidence of infection with three protozoans, Leishmania infantum, Toxoplasma gondii and Neospora cani...

  2. Serosurvey for Leishmania spp., Toxoplasma gondii, Trypanosoma cruzi and Neospora caninum in neighborhood dogs in Curitiba-Paraná, Brazil

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    Caroline Constantino

    Full Text Available Abstract Neighborhood dogs may act as reservoirs for several zoonotic protozoan infections, particularly in urban areas, thus constituting a potential public health threat. Accordingly, the aim of the present study was to evaluate the exposure of neighborhood dogs to four protozoan pathogens in public areas with high levels of human movement in Curitiba, southern Brazil. Blood samples from 26 neighborhood dogs were screened by means of the indirect immunofluorescent antibody test (IFAT for Leishmania spp., Toxoplasma gondii, Trypanosoma cruzi and Neospora caninum, and a questionnaire was answered by the respective keeper. A total of 8/26 dogs (30.7% seroreactive to T. gondii, 3/26 (11.5% to N. caninum and 2/26 (7.7% to both were identified. All the samples were seronegative for T. cruzi and Leishmania spp. Pathogen seroreactivity was not associated with the daily human movements or other epidemiological variables investigated (p > 0.05. In conclusion, the low seroprevalence for T. gondii and N. caninum indicated low environmental and food risk for animal infection and the seronegativity for Leishmania spp. and T. cruzi may reflect the absence of these pathogens in urban areas of Curitiba. Moreover, neighborhood dogs may be used as environmental sentinels for the presence of protozoan pathogens and their vectors.

  3. Occurrence of anti-Leishmania spp., Neospora caninum, and Toxoplasma gondii antibodies in dog sera from Veterinary Hospital from Universidade Estadual de LondrinaOcorrência de anticorpos contra Leishmania spp., Neospora caninum E Toxoplasma gondii em soros de cães atendidos no Hospital Veterinário da Universidade Estadual de Londrina-Pr

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    Dauton Luiz Zulpo

    2012-10-01

    Full Text Available The aim of this study was to detect the presence of IgG antibodies anti-Leishmania spp., Toxoplasma gondii and Neospora caninum in dogs from a Veterinary Hospital from Universidade Estadual de Londrina. Blood samples from 112 animals were obtained by jugular venipuncture to obtain sera. The samples were tested by indirect immunofluorescence to detect antibodies anti-Leishmania spp., anti-N. caninum and anti-T. gondii. Thirteen (11.61%, 25 (22.32%, and 57 (50.89% samples were positive for Leishmania spp., N. caninum, and T. gondii, respectively. The co-presence of anti-Leishmania spp. and N. caninum was observed in 6 (5.36%, anti-Leishmania spp. and anti-T. gondii in 8 (14.7%, and anti-N. caninum and anti-T. gondii in 18 (16.07% samples. The co-presence of anti-Leishmania spp., anti-N. caninum and anti-T. gondii was observed in 5 (4.46% dogs. There was a higher prevalence of Leishmania in Toxoplasma and Neospora positive animals, however, these results were not statistically significant (range p = 0.052 p = 0.06. The dogs have an important role in the epidemiological cycle of these diseases, which are important in animal and public health. The northern state of Paraná is an endemic area for human cutaneous leishmaniasis, therefore, studies should be conducted to uncover the real role of dogs as reservoirs of Leishmania to humans in the state. O objetivo do presente trabalho foi detectar a presença de anticorpos contra Leishmania spp., Neospora caninum e Toxoplasma gondii em cães atendidos no Hospital Veterinário, da Universidade Estadual de Londrina. Amostras de 112 animais foram obtidas por venopunção jugular ou cefálica com posterior obtenção dos soros. Estas foram submetidas à técnica de imunofluorescência indireta para detecção de anticorpos da classe IgG anti-Leishmania spp, anti-N. caninum e anti-T. gondii. Dos 112 soros examinados, 13 (11,61%, 25 (22,32% e 57 (50,89% foram positivos para Leishmania spp., N. caninum e T

  4. Serological cross-reactivity of Trypanosoma cruzi, Ehrlichia canis, Toxoplasma gondii, Neospora caninum and Babesia canis to Leishmania infantum chagasi tests in dogs

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    Maurício Franco Zanette

    2014-01-01

    Full Text Available Introduction: The aim of this study was to evaluate the serological cross-reactivity between Leishmania sp. and other canine pathogens. Methods: Positive serum samples for Ehrlichia canis, Babesia canis, Toxoplasma gondii, Neospora caninum and Trypanosoma cruzi were tested using three serological methods enzyme linked immunosorbent assay (ELISA, indirect immunofluorescent antibody test (IFAT and Kalazar Detect™, for canine visceral leishmaniasis. Results: Of the 57 dog samples tested, 24 (42.1% tested positive using one of the three serological methods: 10/57 (17.5% for ELISA, 11/57 (19.3% for IFAT and 3/57 (5.3% for Kalazar Detect™. Conclusions: Our results demonstrated that the presence of other infectious agents may lead to cross-reactivity on leishmaniasis serological tests.

  5. Effect of clinically approved HDAC inhibitors on Plasmodium, Leishmania and Schistosoma parasite growth

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    Ming Jang Chua

    2017-04-01

    Full Text Available Malaria, schistosomiasis and leishmaniases are among the most prevalent tropical parasitic diseases and each requires new innovative treatments. Targeting essential parasite pathways, such as those that regulate gene expression and cell cycle progression, is a key strategy for discovering new drug leads. In this study, four clinically approved anti-cancer drugs (Vorinostat, Belinostat, Panobinostat and Romidepsin that target histone/lysine deacetylase enzymes were examined for in vitro activity against Plasmodium knowlesi, Schistosoma mansoni, Leishmania amazonensis and L. donovani parasites and two for in vivo activity in a mouse malaria model. All four compounds were potent inhibitors of P. knowlesi malaria parasites (IC50 9–370 nM, with belinostat, panobinostat and vorinostat having 8–45 fold selectivity for the parasite over human neonatal foreskin fibroblast (NFF or human embryonic kidney (HEK 293 cells, while romidepsin was not selective. Each of the HDAC inhibitor drugs caused hyperacetylation of P. knowlesi histone H4. None of the drugs was active against Leishmania amastigote or promastigote parasites (IC50 > 20 μM or S. mansoni schistosomula (IC50 > 10 μM, however romidepsin inhibited S. mansoni adult worm parings and egg production (IC50 ∼10 μM. Modest in vivo activity was observed in P. berghei infected mice dosed orally with vorinostat or panobinostat (25 mg/kg twice daily for four days, with a significant reduction in parasitemia observed on days 4–7 and 4–10 after infection (P < 0.05, respectively.

  6. Fatores associados à soropositividade para Babesia, Toxoplasma, Neospora e Leishmania em cães atendidos em nove clínicas veterinárias do município de Lavras, MG Factors associated the seropositivity for Babesia, Toxoplasma, Neospora e Leishmania in dogs attended at nine veterinary clinics in the municipality of Lavras, MG

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    Antônio Marcos Guimarães

    2009-12-01

    Full Text Available O objetivo deste estudo foi determinar a frequência e avaliar a influência da idade, sexo e raça na soropositividade anti-Babesia canis, Toxoplasma gondii, Leishmania (L. chagasi e Neospora caninum, por meio da reação de imunofluorescência indireta (RIFI, em amostras de soros coletadas de cães atendidos em nove clínicas veterinárias particulares do município de Lavras, MG, no período de agosto de 2000 a abril de 2002. De 300 cães, 73,3% foram soropositivos (RIFI > 1:80 para B. canis, e houve um aumento significativo de reagentes (p 1:40. Para T. gondii, de 218 cães, 60,7% foram positivos (RIFI > 1:16. Em 228 amostras de soros, 3,1% foram positivas (RIFI > 1:50 para N. caninum. Infecções por B. canis e T. gondii são endêmicas em cães atendidos em clínicas veterinárias particulares em Lavras. Não há evidências de casos autóctones de leishmaniose visceral canina em Lavras. Além disso, a infecção por N. caninum é pouco comum em cães criados na zona urbana do município.The aim of the present study was to determine the frequency and evaluate the influence of age, sex and breed in seropositivity anti-Babesia canis, Toxoplasma gondii, Leishmania (L. chagasi and Neospora caninum, by means of the indirect immunofluorescence antibody test (IFAT, in serum samples collected from dogs attended in nine private veterinary clinics in municipality of Lavras, Minas Gerais, Brazil, from August 2000 to April 2002. Of 300 dogs, 73.3% were seropositive (IFAT > 1:80 to B. canis, and there was a significant increase (p 1:40. T. gondii, of 218 dogs, 60.7% were positive (IFAT > 1:16. In 228 serum samples, 3.1% were positive (IFAT > 1:50 to N. caninum. Infections to B. canis and T. gondii occur as endemic form in dogs examined at private veterinary clinics in Lavras. There is no evidence that there are autochthonous cases of canine visceral leishmaniosis in Lavras. Besides this the infection by N. caninum is uncommon in dogs breed at the

  7. Presence of antibodies against Toxoplasma gondii, Neospora caninum and Leishmania infantum in dogs from Piauí Presença de anticorpos anti-Toxoplasma gondii, Neospora caninum e Leishmania infantum em cães do Piauí

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    Marcos Gomes Lopes

    2011-06-01

    Full Text Available This study aimed to evaluate the presence of antibodies against Neospora caninum, Toxoplasma gondii and Leishmania infantum in dogs attended at the Veterinary Hospital of the Federal University of Piauí, Northeastern Brazil, where there are no reports of the occurrence of N. caninum and T. gondii in dogs. Serum samples from 530 dogs of genders, different ages and breeds from the municipality of Teresina and nearby towns were analyzed using three indirect fluorescent antibody tests, each one targeting one of the three agents. The associations between the parasites and gender, breed and age of the dogs were assessed by the chi-square test (p > 0.05. The occurrence of antibodies to N. caninum, T. gondii and L. infantum was 3.2, 18.0 and 78.1%, respectively. Toxoplasma gondii was more frequently found in older dogs (p 0.05. The results confirm the exposure of dogs to these parasites in the State of Piauí.Este estudo teve como objetivo avaliar a presença de anticorpos contra Neospora caninum, Toxoplasma gondii e Leishmania infantum em cães atendidos no Hospital Veterinário da Universidade Federal do Piauí, Teresina, Piauí, onde não há relatos de ocorrência de N. caninum e T. gondii em cães. Amostras de soro de 530 cães de ambos os sexos, diferentes idades e raças do município de Teresina e cidades vizinhas, foram analisados utilizando três testes de imunofluorescência indireta para cada um dos três agentes. Associação entre os parasitas e o sexo, a raça e a idade dos cães foram analisadas pelo teste do qui-quadrado (p > 0,05. Ocorrência de anticorpos para N. caninum, T. gondii e L. infantum foi de 3,2, 18,0 e 78,1%, respectivamente. Toxoplasma gondii foi mais freqüente em cães mais velhos (p > 0,05, enquanto L. infantum apresentou maior freqüência em animais com idade entre um e três anos (p > 0,05. Para avaliar possíveis associações entre a presença de anticorpos anti-N. caninum e anti-T. gondii com infecção por

  8. Presence of anti-Toxoplasma gondii, -Neospora caninum, -Leishmania spp. and -Ehrlichia canis antibodies in free-ranging maned wolves (Chrysocyon brachyurus in the northeastern region of the state of São Paulo, Brazil

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    Solange Oliveira

    2016-09-01

    Full Text Available O lobo-guará (Chrysocyon brachyurus habita o ecossistema de Cerrado e é considerado o maior canídeo da América do Sul e uma espécie ameaçada de extinção pela "International Union for Conservation of Nature" (IUNC. O objetivo desse estudo foi investigar a presença de anticorpos anti-Toxoplasma gondii, -Neospora caninum, -Leishmania spp. e -Ehrlichia canis em lobos-guará da região nordeste do estado de São Paulo, Brasil. Das 17 amostras de soro testadas por meio da reação de imunofluorescência indireta (RIFI, 88,2% (15/17, 17,6% (3/17 e 52,9% (9/17 apresentaram anticorpos anti-T. gondii, -Leishmania spp. e -E. canis, respectivamente. Todos os animais testados foram soronegativos para N. caninum. Esses resultados indicam a exposição dos lobos-guará dessa região aos agentes pesquisados. A presença de um complexo industrial, agricultura extensiva e fragmentação de habitat na região nordeste do estado de São Paulo, favorece a proximidade desses animais silvestres a ambientes urbanos o que pode contribuir para a transmissão de doenças entre os animais silvestres, domésticos e o homem.

  9. Neospora caninum and Wildlife

    Science.gov (United States)

    Almería, Sonia

    2013-01-01

    Bovine neosporosis caused by Neospora caninum is among the main causes of abortion in cattle nowadays. At present there is no effective treatment or vaccine. Serological evidence in domestic, wild, and zoo animals indicates that many species have been exposed to this parasite. However, many aspects of the life cycle of N. caninum are unknown and the role of wildlife in the life cycle of N. caninum is still not completely elucidated. In North America, there are data consistent with a sylvatic cycle involving white tailed-deer and canids and in Australia a plausible sylvatic cycle could be occurring between wild dogs and their macropod preys. In Europe, a similar sylvatic cycle has not been established but is very likely. The present review is a comprehensive and up to date summary of the current knowledge on the sylvatic cycle of N. caninum, species affected and their geographical distribution. These findings could have important implications in both sylvatic and domestic cycles since infected wildlife may influence the prevalence of infection in cattle farms in the same areas. Wildlife will need to be taken into account in the control measures to reduce the economical losses associated with this important disease in cattle farms. PMID:27335866

  10. A Review of Neospora caninum and Neospora-like Infections in Animals

    OpenAIRE

    Dubey, J. P.

    1992-01-01

    Neospora caninum is a recently recognized protozoan parasite of animals. Until 1988, itwas misdiagnosed as Toxoplasma gondii. Neospora caninum or Neospora-like parasites cause paralysisand death in dogs and neonatal mortality and abortion in cattle, sheep, goats and horses. Its life cycle isnot known. Tachyzoites and tissue cysts are the only asexual stages known and the carnivorous definitivehost is not known. Transplacental transmission is the only known natural route of infection.

  11. Seroprevalence of Neospora spp. in horses in South of Iran.

    Science.gov (United States)

    Moraveji, M; Hosseini, M H; Amrabadi, O; Rahimian, A; Namazi, F; Namavari, M

    2011-12-01

    Neospora caninum, an apicomplexan protozoan parasite, is recognized as a major cause of abortion in cattle. However, limited information is presently available on the seroprevalence of Neospora antibodies in horses worldwide. The aim of the present study is to determine serological prevalence of Neospora infection in horses in Iran. Blood samples were obtained from 200 horses and tested for serum antibodies against Neospora spp. by the Neospora modified direct agglutination test (N-MAT). Antibodies were found in 64 (32%) horses being tested with titers of 1:80. This is the first serological survey for Neospora antibodies performed on horses in Iran.

  12. Neospora then and now: prevalence of Neospora caninum in Maritime Canada in 1979, 1989, and 1998.

    OpenAIRE

    Keefe, G P; VanLeeuwen, J A

    2000-01-01

    The seroprevalence of Neospora caninum was compared among New Brunswick, Nova Scotia, and Prince Edward Island in 1998, 1989, and 1979. In 1998, the seroprevalence was lowest in Prince Edward Island, where it was the same as in 1989. Neospora caninum was present in 1979, but at a lower prevalence.

  13. Seroprevalence of Toxoplasma gondii and Neospora caninum ...

    African Journals Online (AJOL)

    The aim of this study was to compare the seroprevalence of Toxoplasma gondii and Neospora caninum in goats from two Argentinean provinces raised under different management conditions. A total of 2922 serum samples from adult goats of Córdoba (n=2187) and Buenos Aires provinces (n= 735), Argentina, were ...

  14. Plasmodium falciparum

    Indian Academy of Sciences (India)

    Development of nuclear DNA markers for evolutionary studies in. Plasmodium falciparum. CELIA THOMAS, SNEH SHALINI, N. RAGHAVENDRA, MEENAKSHI CHOUDHARY, ANJU VERMA,. HEMA JOSHI, A. P. DASH and APARUP DAS*. National Institute of Malaria Research (ICMR), 22 Sham Nath Marg, Delhi 110 054, ...

  15. Seroprevalence of Toxoplasma gondii and Neospora caninum in ...

    African Journals Online (AJOL)

    Background: Toxoplasma gondii and Neospora caninum are protozoans infecting a wide range of mammals; the etiologic agents of Toxoplasmosis and Neosporosis respectively, This study investigated the prevalence of antibodies to Toxoplasma gondii and Neospora caninum in dogs from southwestern Nigeria. Materials ...

  16. NEOSPORA CANINUM ANTIBODIES IN WILD CARNIVORES FROM SPAIN

    Science.gov (United States)

    Serum samples from 251 wild carnivores from different regions of Spain were tested for antibodies to Neospora caninum by the commercial competitive screening enzyme linked immunosorbent assay (c-ELISA) and confirmed by Neospora agglutination test (NAT) and/or by indirect fluorescent antibody test (I...

  17. Neospora caninum Infection in Nigeris: Evidence of Occurrence in ...

    African Journals Online (AJOL)

    Neospora caninum is a protozoan parasite causing significant economic losses due to abortions, birth of weak calves, fertility problems, reduced milk production and increased culling. The objective of this study was to investigate the presence of Neospora caninum in cattle imported to Nigeria for dairy purpose and also in ...

  18. Serum antibody to neospora caninum in indigenous African cattle ...

    African Journals Online (AJOL)

    Sera from 78 indigenous cattle were tested, by the indirect fluorescent antibody technique (IFAT), for neosporosis. In vitro cultured Neospora caninum was used as antigen. Antibodies to Neospora at titres 1/640 and above were detected in two samples (2.6%), a titre considered diagnostic for the disease. All the other serum ...

  19. Immunopathological Features of Canine Myocarditis Associated with Leishmania infantum Infection

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    Alessandro Costagliola

    2016-01-01

    Full Text Available Myocarditis associated with infectious diseases may occur in dogs, including those caused by the protozoa Neospora caninum, Trypanosoma cruzi, Babesia canis, and Hepatozoon canis. However, although cardiac disease due to Leishmania infection has also been documented, the immunopathological features of myocarditis have not been reported so far. The aim of this study was to examine the types of cellular infiltrates and expression of MHC classes I and II in myocardial samples obtained at necropsy from 15 dogs with an established intravitam diagnosis of visceral leishmaniasis. Pathological features of myocardium were characterized by hyaline degeneration of cardiomyocytes, necrosis, and infiltration of mononuclear inflammatory cells consisting of lymphocytes and macrophages, sometimes with perivascular pattern; fibrosis was also present in various degrees. Immunophenotyping of inflammatory cells was performed by immunohistochemistry on cryostat sections obtained from the heart of the infected dogs. The predominant leukocyte population was CD8+ with a fewer number of CD4+ cells. Many cardiomyocytes expressed MHC classes I and II on the sarcolemma. Leishmania amastigote forms were not detected within macrophages or any other cell of the examined samples. Our study provided evidence that myocarditis in canine visceral leishmaniasis might be related to immunological alterations associated with Leishmania infection.

  20. Immunopathological Features of Canine Myocarditis Associated with Leishmania infantum Infection

    Science.gov (United States)

    Piegari, Giuseppe; Otrocka-Domagala, Iwona; Ciccarelli, Davide; Iovane, Valentina; Oliva, Gaetano; Russo, Valeria; Rinaldi, Laura; Papparella, Serenella; Paciello, Orlando

    2016-01-01

    Myocarditis associated with infectious diseases may occur in dogs, including those caused by the protozoa Neospora caninum, Trypanosoma cruzi, Babesia canis, and Hepatozoon canis. However, although cardiac disease due to Leishmania infection has also been documented, the immunopathological features of myocarditis have not been reported so far. The aim of this study was to examine the types of cellular infiltrates and expression of MHC classes I and II in myocardial samples obtained at necropsy from 15 dogs with an established intravitam diagnosis of visceral leishmaniasis. Pathological features of myocardium were characterized by hyaline degeneration of cardiomyocytes, necrosis, and infiltration of mononuclear inflammatory cells consisting of lymphocytes and macrophages, sometimes with perivascular pattern; fibrosis was also present in various degrees. Immunophenotyping of inflammatory cells was performed by immunohistochemistry on cryostat sections obtained from the heart of the infected dogs. The predominant leukocyte population was CD8+ with a fewer number of CD4+ cells. Many cardiomyocytes expressed MHC classes I and II on the sarcolemma. Leishmania amastigote forms were not detected within macrophages or any other cell of the examined samples. Our study provided evidence that myocarditis in canine visceral leishmaniasis might be related to immunological alterations associated with Leishmania infection. PMID:27413751

  1. Neospora caninum: Cloning and expression of a gene coding for cytokine-inducing Neospora caninum profilin

    Science.gov (United States)

    Profilins are actin-binding proteins that in T. gondii stimulate innate immunity in mice by binding Toll-like receptors (TLR) on dendritic cells (DC) leading to release of inflammatory cytokines, primarily IL-12 and IFN-'. The purpose of the present study was to characterize Neospora caninum profil...

  2. Redescription of Neospora caninum and its differentiation from related coccidia

    Czech Academy of Sciences Publication Activity Database

    Dubey, J. P.; Barr, B. C.; Barta, J. R.; Bjerkas, I.; Bjorkman, C.; Blagburn, B. L.; Bowman, D. D.; Buxton, D.; Ellis, J. T.; Gottstein, B.; Hemphill, A.; Hill, D. E.; Howe, D. K.; Jenkins, M. C.; Kobayashi, Y.; Koudela, Břetislav; Marsh, A. E.; Mattsson, J. G.; McAllister, M. M.; Modrý, David; Omata, Y.; Sibley, L. D.; Speer, C. A.; Trees, A. J.; Uggla, A.; Upton, S. J.; Wlliams, D. J. L.; Lindsay, D. S.

    2002-01-01

    Roč. 32, č. 8 (2002), s. 929-946 ISSN 0020-7519 Institutional research plan: CEZ:AV0Z6022909 Keywords : Neospora caninum * coccidia * tachyzoizes Subject RIV: EG - Zoology Impact factor: 2.850, year: 2002

  3. Plasmodium falciparum metacaspase PfMCA-1 triggers a z-VAD-fmk inhibitable protease to promote cell death.

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    Benoît Meslin

    Full Text Available Activation of proteolytic cell death pathways may circumvent drug resistance in deadly protozoan parasites such as Plasmodium falciparum and Leishmania. To this end, it is important to define the cell death pathway(s in parasites and thus characterize proteases such as metacaspases (MCA, which have been reported to induce cell death in plants and Leishmania parasites. We, therefore, investigated whether the cell death function of MCA is conserved in different protozoan parasite species such as Plasmodium falciparum and Leishmania major, focusing on the substrate specificity and functional role in cell survival as compared to Saccharomyces cerevisae. Our results show that, similarly to Leishmania, Plasmodium MCA exhibits a calcium-dependent, arginine-specific protease activity and its expression in yeast induced growth inhibition as well as an 82% increase in cell death under oxidative stress, a situation encountered by parasites during the host or when exposed to drugs such as artemisins. Furthermore, we show that MCA cell death pathways in both Plasmodium and Leishmania, involve a z-VAD-fmk inhibitable protease. Our data provide evidence that MCA from both Leishmania and Plasmodium falciparum is able to induce cell death in stress conditions, where it specifically activates a downstream enzyme as part of a cell death pathway. This enzymatic activity is also induced by the antimalarial drug chloroquine in erythrocytic stages of Plasmodium falciparum. Interestingly, we found that blocking parasite cell death influences their drug sensitivity, a result which could be used to create therapeutic strategies that by-pass drug resistance mechanisms by acting directly on the innate pathways of protozoan cell death.

  4. Gluconeogenesis in Leishmania mexicana

    Science.gov (United States)

    Rodriguez-Contreras, Dayana; Hamilton, Nicklas

    2014-01-01

    Gluconeogenesis is an active pathway in Leishmania amastigotes and is essential for their survival within the mammalian cells. However, our knowledge about this pathway in trypanosomatids is very limited. We investigated the role of glycerol kinase (GK), phosphoenolpyruvate carboxykinase (PEPCK), and pyruvate phosphate dikinase (PPDK) in gluconeogenesis by generating the respective Leishmania mexicana Δgk, Δpepck, and Δppdk null mutants. Our results demonstrated that indeed GK, PEPCK, and PPDK are key players in the gluconeogenesis pathway in Leishmania, although stage-specific differences in their contribution to this pathway were found. GK participates in the entry of glycerol in promastigotes and amastigotes; PEPCK participates in the entry of aspartate in promastigotes, and PPDK is involved in the entry of alanine in amastigotes. Furthermore, the majority of alanine enters into the pathway via decarboxylation of pyruvate in promastigotes, whereas pathway redundancy is suggested for the entry of aspartate in amastigotes. Interestingly, we also found that l-lactate, an abundant glucogenic precursor in mammals, was used by Leishmania amastigotes to synthesize mannogen, entering the pathway through PPDK. On the basis of these new results, we propose a revision in the current model of gluconeogenesis in Leishmania, emphasizing the differences between amastigotes and promastigotes. This work underlines the importance of studying the trypanosomatid intracellular life cycle stages to gain a better understanding of the pathologies caused in humans. PMID:25288791

  5. A transgenic Neospora caninum strain based on mutations of the dihydrofolate reductase-thymidylate synthase gene.

    Science.gov (United States)

    Pereira, Luiz Miguel; Baroni, Luciana; Yatsuda, Ana Patrícia

    2014-03-01

    Neospora caninum is an Apicomplexa parasite related to abortion and losses of fertility in cattle. The amenability of Toxoplasma gondii and Plasmodium to genetic manipulation offers several tools to determine the invasion and replication processes, which support posterior strategies related to the combat of these diseases. For Plasmodium the use of pyrimethamine as an auxiliary drug on malaria treatment has been affected by the rise of resistant strains and the analyses on Dihydrofolate reductase-thymidylate synthase (DHFR-TS) gene indicated several point mutations. In this work we developed a method for stable insertion of genes based on resistance to pyrimethamine. For that, the coding sequence of NcDHFR-TS (Dihydrofolate reductase-thymidylate synthase) was point mutated in two amino acids, generating DHFRM2M3. The DHFRM2M3 flanked by the promoter and 3'UTR of Ncdhfr-ts (Ncdhfr-DHFRM2M3) conferred resistance to pyrimethamine after transfection. For illustration of stability and expression, the cassette Ncdhfr-DHFRM2M3 was ligated to the reporter gene Lac-Z (β-galactosidase enzyme) controlled by the N. caninum tubulin promoter and was transfected and selected in N. caninum. The cassette was integrated into the genome and the selected tachyzoites expressed Lac-Z, allowing the detection of tachyzoites by the CPRG reaction and X-gal precipitation. The obtainment of transgenic N. caninum resistant to pyrimethamine confirms the effects on DHFR-TS among the Apicomplexa members and will support future approaches on pholate inhibitors for N. caninum prophylaxis. The construction of stable tachyzoites based on vectors with N. caninum promoters initiates the molecular manipulation of this parasite independently of T. gondii. Copyright © 2014. Published by Elsevier Inc.

  6. Neospora caninum in crows from Israel.

    Science.gov (United States)

    Salant, H; Mazuz, M L; Savitsky, I; Nasereddin, A; Blinder, E; Baneth, G

    2015-09-15

    A cross-sectional Neospora caninum seroprevalence study was performed on free ranging crows (Corvus cornix, Corvus monedula and Corvus splendens) from Israel in order to assess their exposure to this pathogen and evaluate their role as potential hosts or as sentinels of infection. Using the modified agglutination test (MAT) with a cutoff titer of 1:100, 30 out of 183 crows (16.4%) were found to be N. caninum seropositive. Positive results were validated and confirmed by the indirect fluorescent antibody test (IFAT). There was 100% agreement between tests when cut-off titers of 1:50 and 1:100 were applied for the IFAT and MAT, respectively. PCR analysis of brain extracts from all crows resulted in the detection of N. caninum DNA for the first time in crows belonging to two species, C. cornix and C. monedula. The high N. caninum seroprevalence in crows suggests that widespread exposure to infection with N. caninum exists especially in central and northern Israel and that crows may act as suitable markers for disease prevalence in the areas in which they are found. Copyright © 2015 Elsevier B.V. All rights reserved.

  7. Increased transmission potential of Leishmania major/Leishmania infantum hybrids

    OpenAIRE

    Volf, Petr; Benkova, Ivana; Myskova, Jitka; Sadlova, Jovana; Campino, Lenea; Ravel, Christophe

    2007-01-01

    Development of Leishmania infantum/Leishmania major hybrids was studied in two sand fly species. In Phlebotomus papatasi, which supported development of L. major but not L. infantum, the hybrids produced heavy late-stage infections with high numbers of metacyclic promastigotes. In the permissive vector Lutzomyia longipalpis, all Leishmania strains included in this study developed well. Hybrids were found to express L. major lipophosphoglycan, apparently enabling them to survive in P. papatasi...

  8. Seroprevalence of Neospora spp. in horses from Central Province of ...

    African Journals Online (AJOL)

    HP

    2013-02-27

    Feb 27, 2013 ... Vet. Parasitol. 79:269-274. Hoane JS, Gennari SM, Dubey JP, Ribeiro MG, Borges AS Yai, LE,. Aguiar DM, Cavalcante GT, Bonesi GL, Howe DK (2006). Prevalence of Sarcocystis neurona and Neospora spp. infection in horses from. Brazil based on presence of serum antibodies to parasite surface antigen.

  9. Comparative gene expression profiling of Neospora caninum strains

    Science.gov (United States)

    To understand the genetic basis of virulence, gene expression profiles of a temperature-sensitive strain (NCts-8) and its wild type (NC-1) of Neospora caninum were characterized and compared using a high-density microarray with approximately 63,000 distinct oligonucleotides. Each sequence is represe...

  10. Significance of Neospora caninum in cattle farming

    Directory of Open Access Journals (Sweden)

    Ilić Tamara

    2006-01-01

    Full Text Available Neospora caninum is an obligate intracellular protozoan parasite which primarily causes diseases in dogs and cattle all over the world. It was first described in Norway in the mid-eighties in dogs, after which, until the present time, clinical neosporosis was proven in sheep, goats, deer, rhinoceroses, horses, and experimental rodents. Antibodies against N. caninum have been found also in the serum of water buffalo, red and gray foxes, coyotes, camels, and felines. Due to the similarity of this Coccidia with Toxoplasma gondi, the neosporosis was for a series of years incorrectly diagnozed as toxoplasmosis. Domestic canines, dogs, are the only real host for N. caninum. Its life cycle covers three stages of development: tachyzoites, tissue cysts and oocysts. Carnivores are infected by ingesting parts of infected tissue which contain tissue cysts with bradyzoites. The dominant pathway of transmission of this cause in cattle is transplacentary infection, but cattle can also be infected by ingestion of feed or water contaminated by sporulated oo-cysts of N. caninum. Bitches can be subclinical carriers of the parasite, when they pass on the cause transplacentarily, which results in more than one litter being born with the infection. Neosporosis today appears as the main cause of abortions and neonatal deaths in dairy cows and fattening cattle in almost all parts of the world, but with the highest incidence in the United States (US, New Zealand, The Netherlands, and Germany. The treatment of this disease has not been fully determined, but medicines used for the treatment of toxoplasmosis have yielded certain good results. There is no verified vaccine that would prevent undesired abortions in cattle. .

  11. The first detection of Neospora caninum DNA in brains of calves in Poland

    OpenAIRE

    Wisniewski M.; Cabaj W.; Moskwa B.; Wedrychowicz H.

    2002-01-01

    The recognition of prevalence ofNeospora caninum infections in Poland is very poor. Vertical transmission of N. caninum has been shown to be a major route of infection in cattle. In the present study we examined the utility of PCR methods in detecting Neospora caninum DNA in brains of calves born from mothers with a high liter of anti-Neospora antibodies. Conventional and nested PCR reactions were performed on DNA extracted from brain tissue of Neospora-suspected calves using primers compleme...

  12. Diagnostic Antigens of Leishmania.

    Science.gov (United States)

    1994-01-31

    L. major (LTM p-2), L. major (Friedlander), and Trypanosoma cruzi (MHOM/CH/00/Tulahuen C2) were used. Leishmania promastigotes and T. cruzi ...some weak hybridization was observed with L. amazonensis, but none was seen with L. braziliensis, L. guyanensis, or T cruzi . A similar, overlapping... cruzi (8) have been previously isolated by us. To address this possibility in rLt-1, a portion of the repeat was expressed separately as rLt-lr. The

  13. Peroxisome proliferator-activated receptor-γ-mediated polarization of macrophages in Neospora caninum infection.

    Science.gov (United States)

    He, Xuexiu; Gong, Pengtao; Wei, Zhengkai; Liu, Weijian; Wang, Weili; Li, Jianhua; Yang, Zhengtao; Zhang, Xichen

    2017-07-01

    Neospora caninum is an apicomplexan parasite closely related Toxoplasma gondii, which causes neurological disease and abortion in multiple animal species. Macrophage polarization plays an important role in host immune responses to parasites infection, such as Toxoplasma gondii, Leishmania, Trypanosoma cruzi. However, the dynamics of macrophage polarization, as well as the possible mechanism that regulate macrophage polarization, during N. caninum infection remains unclear. The M1 and M2-phenotypic markers of peritoneal macrophages from mice infected with tachyzoites of Nc-1 were analyzed by flow cytometry (FCM) analysis. Then J774A.1 cells were respectively treated with GW9662 and RGZ, and stimulated by tachyzoites of Nc-1. M1 and M2-phenotypic markers were determined by FCM and ELISA. And the activations of PPAR-γ and NF-κB were determined by Western blotting. In this study, our data showed that macrophages were preferentially differentiated into the M1 type during the acute stage of N. caninum infection, while the level of M2 macrophages significantly increased during the chronic stage of infection. In vitro study, compared with the GW9662 group and RGZ group, N. caninum can promote M2-polarized phenotype through up-regulate the activity of PPAR-γ and inhibting NF-κB activation. In conclusion, this study demonstrated that macrophages are plastic since M1 differentiated macrophages can express M2 markers with N. caninum infection through up-regulating the activity of PPAR-γ and inhibting NF-κB activation and may be providing new insights for the prevention and treatment of N. caninum infection. Copyright © 2017. Published by Elsevier Inc.

  14. Genomic Organization of Leishmania Species

    Directory of Open Access Journals (Sweden)

    B Kazemi

    2011-09-01

    Full Text Available Leishmania is a protozoan parasite belonging to the family Trypanosomatidae, which is found among 88 different countries. The parasite lives as an amastigote in vertebrate macro­phages and as a promastigote in the digestive tract of sand fly. It can be cultured in the laboratory us­ing appropriate culture media. Although the sexual cycle of Leishmania has not been observed during the promastigote and amastigote stages, it has been reported by some researchers. Leishma­nia has eukaryotic cell organization. Cell culture is convenient and cost effective, and because posttranslational modifications are common processes in the cultured cells, the cells are used as hosts for preparing eukaryotic recombinant proteins for research. Several transcripts of rDNA in the Leishmania genome are suitable regions for conducting gene transfer. Old World Leishmania spp. has 36 chromosomes, while New World Leishmania spp. has 34 or 35 chromo­somes. The genomic organization and parasitic characteristics have been investigated. Leishmania spp. has a unique genomic organization among eukaryotes; the genes do not have introns, and the chromosomes are smaller with larger numbers of genes confined to a smaller space within the nucleus. Leishmania spp. genes are organized on one or both DNA strands and are transcribed as polycistronic (prokaryotic-like transcripts from undefined promoters. Regulation of gene expres­sion in the members of Trypanosomatidae differs from that in other eukaryotes. The trans-splic­ing phenomenon is a necessary step for mRNA processing in lower eukaryotes and is observed in Leishmania spp. Another particular feature of RNA editing in Leishmania spp. is that mitochon­drial genes encoding respiratory enzymes are edited and transcribed. This review will discuss the chromosomal and mitochondrial (kinetoplast genomes of Leishmania spp. as well as the phenome­non of RNA editing in the kinetoplast genome.

  15. Review of Neospora caninum and neosporosis in animals

    Science.gov (United States)

    2003-01-01

    Neospora caninum is a coccidian parasite of animals. It is a major pathogen for cattle and dogs and it occasionally causes clinical infections in horses, goats, sheep, and deer. Domestic dogs are the only known definitive hosts for N. caninum. It is one of the most efficiently transmitted parasite of cattle and up to 90% of cattle in some herds are infected. Transplacental transmission is considered the major route of transmission of N. caninum in cattle. Neospora caninum is a major cause of abortion in cattle in many countries. To elicit protective immunity against abortion in cows that already harbor a latent infection is a major problem. This paper reviews information on biology, diagnosis, epidemiology and control of neosporosis in animals. PMID:12666725

  16. Epidemiology and control of neosporosis and Neospora caninum.

    Science.gov (United States)

    Dubey, J P; Schares, G; Ortega-Mora, L M

    2007-04-01

    Neospora caninum is a protozoan parasite of animals. Until 1988, it was misidentified as Toxoplasma gondii. Since its first recognition in dogs in 1984 and the description of the new genus and species Neospora caninum in 1988, neosporosis has emerged as a serious disease of cattle and dogs worldwide. Abortions and neonatal mortality are a major problem in livestock operations, and neosporosis is a major cause of abortion in cattle. Although antibodies to N. caninum have been reported, the parasite has not been detected in human tissues. Thus, the zoonotic potential is uncertain. This review is focused mainly on the epidemiology and control of neosporosis in cattle, but worldwide seroprevalences of N. caninum in animals and humans are tabulated. The role of wildlife in the life cycle of N. caninum and strategies for the control of neosporosis in cattle are discussed.

  17. Equine protozoal myeloencephalitis caused by Neospora hughesi in an adult horse in Saskatchewan

    Science.gov (United States)

    Wobeser, Bruce K.; Godson, Dale L.; Rejmanek, Daniel; Dowling, Patricia

    2009-01-01

    A protozoal parasite identified as Neospora hughesi was found in inflammatory lesions in the central nervous system of a Canadian-born adult horse presented with neurological signs. This is believed to be the first case of equine protozoal myeloencephalitis (EPM) caused by Neospora hughesi in a horse outside of the United States. PMID:19881924

  18. Gray wolf (Canis lupus) is a natural definitive host for Neospora caninum

    Science.gov (United States)

    The gray wolf (Canis lupus) was found to be a new natural definitive host for Neospora caninum. This finding is based on the recovery of Neospora-like oocysts from the feces of 3 of 73 wolves from Minnesota examined at necropsy, and on successful amplification of N. caninum-specific sequences from ...

  19. Transmission of Neospora caninum between wild and domestic animals

    Science.gov (United States)

    Gondim, L.F.P.; McAllister, M.M.; Mateus-Pinilla, N. E.; Pitt, W.; Mech, L.D.; Nelson, M.E.; Lenarz, M.S.

    2004-01-01

    Neospora caninum is a protozoan parasite that can cause abortions in cows. N. caninum antibody seroprevalence was detected in 64/164 (39%) free-ranging gray wolves from Minnesota, 30/150 (20%) white-tailed deer, and 8/61 (13%) moose. These data are consistent with a sylvatic transmission cycle of N. caninum between cervids and canids. Infection of canids increases the risk of transmitting the parasite to domestic livestock.

  20. Neospora caninum - Associated Abortions in Slovak Dairy Farm.

    Directory of Open Access Journals (Sweden)

    Silvia Špilovská

    2015-03-01

    Full Text Available Neospora caninum is considered one of the major causes of repeated abortions in livestock. This study aimed to determine the seropositivity to N. caninum using indirect ELISA and the influence of the infection on the occurrence of abortions in selected dairy herd in Slovakia.Blood samples were obtained from 490 cattle over a period of two years and were tested for N. caninum antibodies using indirect ELISA.The presence of specific antibodies in the herd was detected in 118 (24.1% cows. According to selected groups; 117 (41.0% cows with a history of abortion, 65 (43.3% heifers and 223 (2.2% cows without abortions were tested positive to Neospora. Vertical transmission of N. caninum dominated in examined herd and the relative risk (RR of dam-daughter seropositivity in progenies of seropositive mothers was 2.1 times higher than in progenies of seronegative dams. Molecular analyses of aborted foetuses of seropositive mothers showed the presence of Neospora DNA. However, 23 (28.1% of heifers born to seronegative cows were seropositive, indicating also the postnatal transmission of the infection from the environment.Study revealed significant correlation between the presence of specific antibodies and the occurrence of abortions, the risk of abortion in seropositive animals was 3.8 times higher than in seronegative ones. Incorrect farm management contributed to spread and circulation of neosporosis in entire dairy herd what could significantly impair the reproduction and economic parameters of breeding.

  1. A case report of Plasmodium vivax , Plasmodium falciparum and ...

    African Journals Online (AJOL)

    India being a tropical country, parasitic infections especially with Plasmodium species are very common in this region. The present case report is that of Plasmodium vivax, Plasmodium falciparum and dengue co‑infection in a 6 months pregnant lady who was timely diagnosed and appropriately treated followed by a ...

  2. Seroprevalensi Neospora caninum pada sapi bali yang dipotong di Rumah Potong Hewan (RPH Denpasar

    Directory of Open Access Journals (Sweden)

    Adryani Ris

    2015-06-01

    Full Text Available Recent years the infection of Neospora caninum parasite has been a significant reproductive disease on cattle. The purpose of this study was to determine the seroprevalence of Neospora caninum in Bali cattle that are slaughtered in Denpasar’s slaughter house.A total of 184 serums was collected and tested using enzyme linked immunosorbent assay (ELISA. The results showed that there were 2 serum samples (1.08% contain Neospora caninum antibodies. While the remaining samples, 182 samples (98.92%, were negative. Though the neosporosis seroprevalence rate in Bali is very low, a sustainable surveylance must be carried out to mitigate the broadness of the disease distribution.

  3. Serological evidence of Neospora caninum in alpacas from eastern Australia.

    Science.gov (United States)

    King, J S; Vaughan, J L; Windsor, P A

    2015-07-01

    The aim of this study was to investigate if there was any serological evidence of Neospora caninum in alpaca populations in south-eastern Australia. Serum samples from 100 alpacas were collected from four farms. All serum samples were screened for N. caninum antibodies using a commercially available competitive ELISA. Of the 100 alpacas sampled, 3 were suspect seropositive for N. caninum. There is natural N. caninum seroprevalence in alpacas in south-eastern Australia; however, it remains undetermined whether or not this infection is currently contributing to reproductive failure in alpacas in Australia. © 2015 Australian Veterinary Association.

  4. Variabilidad adaptativa y patogénica en "Neospora caninum"

    OpenAIRE

    Pérez Zaballos, Francisco José

    2004-01-01

    Neospora caninum es un protozoo parásito que infecta principalmente al perro y al ganado bovino, con estrechas semejanzas biológicas y estructurales con Toxoplasma gondii. Evidencias recientes sugieren la existencia de una marcada variación de las propiedades genéticas y biológicas entre los diferentes aislados del parásito, similar a las observadas en T. gondii. En el primer experimento de esta tesis doctoral, se ha comparado la adaptación de tres aislados de N. caninum a nuevos ambientes, c...

  5. Peptidomimetic and organometallic derivatives of primaquine active against Leishmania infantum.

    Science.gov (United States)

    Vale-Costa, Sílvia; Vale, Nuno; Matos, Joana; Tomás, Ana; Moreira, Rui; Gomes, Paula; Gomes, Maria Salomé

    2012-11-01

    The current treatment of visceral leishmaniasis is made difficult by the low efficacy, elevated costs, low bioavailability, and high toxicity of many of the available drugs. Primaquine, an antimalarial 8-aminoquinoline, displays activity against Leishmania spp., and several of its derivatives have been developed as potential antileishmanial drugs. However, primaquine exhibits low oral bioavailability due to oxidative deamination of its aliphatic chain. We previously developed peptidomimetic and organometallic derivatives of primaquine, with higher resistance to proteolytic degradation and oxidative deamination, which presented significant activity against primaquine-sensitive pathogens such as Plasmodium or Pneumocystis. In light of these relevant findings, we decided to evaluate these compounds against both the promastigote and intramacrophagic amastigote forms of Leishmania infantum, the agent of Mediterranean visceral leishmaniasis. We found that several of these compounds had significant activity against L. infantum. One of the peptidomimetic (3c) and one of the organometallic (7a) derivatives of primaquine were active against the clinically relevant intramacrophagic amastigote form of the parasite, causing >96% reductions in the number of amastigotes per 100 macrophages at 60 and 40 μM, respectively, while being less cytotoxic for host cells than the reference drugs sitamaquine and miltefosine. Hence, compounds 3c and 7a represent new entries toward the development of new antileishmanial leads.

  6. Humoral and cellular immune responses to synthetic peptides of the Leishmania donovani kinetoplastid membrane protein-11

    DEFF Research Database (Denmark)

    Jensen, A T; Gasim, S; Ismail, A

    1998-01-01

    Native kinetoplastid membrane protein-11 (KMP-11), purified from crude extracts of Leishmania donovani parasites, activates T cells from individuals who have recovered from visceral leishmaniasis. In this work we used three 38-mer peptides spanning the amino acid sequence of the L. donovani KMP-11...... as solid-phase ligands in enzyme-linked immunosorbent assays (ELISAs) and as stimulating antigens in lymphoproliferative assays in order to evaluate humoral and cellular immune responses to well-defined sequences of the protein. Antibody reactivity against the three peptides was measured in plasma from 63......-11 peptides was detected in plasma from Sudanese patients suffering from Leishmania major infections and in plasma from Sudanese and Danish patients infected with Plasmodium falciparum. In lymphoproliferative assays, 10 of 17 PBMC isolates from donors previously infected with L. donovani showed...

  7. Effects of toltrazuril and ponazuril on Hammondia heydorni (syn. Neospora caninum) infections in mice.

    Science.gov (United States)

    Darius, Anne Kathrin; Mehlhorn, Heinz; Heydorn, Alfred Otto

    2004-04-01

    Mice infected with tachyzoites of Neospora caninum (syn.: Hammondia heydorni) must be pretreated with cortisone in order to show disease symptoms. This indicates the status of an opportunistic agent of disease. Toltrazuril was an effective curative agent.

  8. Prevalence of antibodies against Neospora spp. and Sarcocystis neurona in donkeys from northeastern Brazil

    Directory of Open Access Journals (Sweden)

    Solange Maria Gennari

    2016-03-01

    Full Text Available Abstract Sarcocystis neurona and Neospora hughesi are coccidian protozoa that can cause neurological illness in horses in America. In this study we report seroprevalence of Neospora spp. andS. neurona in sera of 333 donkeys from the northeastern region of Brazil. Antibodies to Neospora spp. were detected in 2% (7 donkeys of 333 sera tested by the indirect fluorescent antibody test (IFAT with a cut-off dilution of 1:40. Antibodies to S. neurona were found in 3% (10 donkeys of the samples tested by IFAT (cut-off ≥50 and 21% (69 donkeys by the direct agglutination test (SAT ≥50. The SAT and IFAT results for S. neurona showed a poor concordance (value of Kappa=0.051. This is the first report ofNeospora spp. antibodies in Brazilian donkeys and the first detection of antibodies against S. neurona in this animal species.

  9. On the Biological and Genetic Diversity in Neospora caninum

    Directory of Open Access Journals (Sweden)

    John T. Ellis

    2010-03-01

    Full Text Available Neospora caninum is a parasite regarded a major cause of foetal loss in cattle. A key requirement to an understanding of the epidemiology and pathogenicity of N. caninum is knowledge of the biological characteristics of the species and the genetic diversity within it. Due to the broad intermediate host range of the species, worldwide geographical distribution and its capacity for sexual reproduction, significant biological and genetic differences might be expected to exist. N. caninum has now been isolated from a variety of different host species including dogs and cattle. Although isolates of this parasite show only minor differences in ultrastructure, considerable differences have been reported in pathogenicity using mainly mouse models. At the DNA level, marked levels of polymorphism between isolates were detected in mini- and microsatellites found in the genome of N. caninum. Knowledge of what drives the biological differences that have been observed between the various isolates at the molecular level is crucial in aiding our understanding of the epidemiology of this parasite and, in turn, the development of efficacious strategies, such as live vaccines, for controlling its impact. The purpose of this review is to document and discuss for the first time, the nature of the diversity found within the species Neospora caninum.

  10. The in vitro development of Neospora caninum bradyzoites

    Science.gov (United States)

    Weiss, Louis M.; Ma, Yan Fen; Halonen, Sandra; McAllister, Milton M.; Zhang, Yi Wei

    2011-01-01

    Neospora caninum is a recently identified apicomplexan protozoan parasite that is closely related to Toxoplasma gondii. Neospora caninum is of significant economic importance as it causes neurological disease and abortion in numerous animals. Antibodies to BAG1/hsp30 (also known as BAG5), a T. gondii bradyzoite-specific protein, have been demonstrated to react with N. caninum tissue cysts in vivo. Bradyzoite differentiation of N. caninum in vitro was investigated using culture conditions previously utilised for T. gondii in vitro bradyzoite development. Utilising the NC-Liverpool isolate of N. caninum, cyst-like structures developed within 3–4 days of culture of this parasite in human fibroblasts. In addition, an antigen reacting with mAb 74.1.8 (anti-BAG1) and rabbit anti-recombinant BAG1 was demonstrable by immunofluorescence, fluorescence-activated cell sorter, and immunoblot analyses. Expression of this antigen was increased by stress conditions, similar to that which has been described for T. gondii bradyzoite induction. Cyst-wall formation in vitro, as assayed by lectin binding, did not occur as readily for N. caninum as it does for T. gondii. PMID:10608459

  11. Neospora caninum seropositivity and reproductive risk factors in dogs.

    Science.gov (United States)

    Robbe, Domenico; Passarelli, Alessandra; Gloria, Alessia; Di Cesare, Angela; Capelli, Gioia; Iorio, Raffaella; Traversa, Donato

    2016-05-01

    Despite the importance of Neospora caninum in veterinary medicine, knowledge of distribution of neosporosis in dog populations in some countries is still poor. The aims of the present study were to determine the occurrence of anti-N. caninum antibodies in one-hundred dogs living in cattle farms or dog breedings in central Italy and to evaluate the risk factors associated with seropositivity. The incidence of reproductive system disorders (e.g. infertility after first pregnancy) was also evaluated. Serum from breeding and farm dogs was tested to an indirect immunofluorescent antibody test (IFAT) to assess the occurrence of seropositivity. Management and individual data were collected and analysed both by linear and logistic multiple-regression models to find reliable predictors of seroprevalence and anti-N. caninum antibody level. The seropositivity for N. caninum was 32%. Dogs reared for breeding and presence of cattle on the farm were associated with seropositivity for N. caninum. Dogs living in the cattle farms showed a higher seropositivity for N. caninum (46%) compared with those living in dogs breeding (18%) (P Neospora seropositivity in dog breedings may appear relatively low if compared with that found in dogs living with livestock, this infection, apparently underestimated, should be considered as a potential serious problem in canine medicine. Copyright © 2016 Elsevier Inc. All rights reserved.

  12. Incidence and vertical transmission rate of Neospora caninum in sheep.

    Science.gov (United States)

    Filho, Paulo César G A; Oliveira, Júnior M B; Andrade, Muller R; Silva, José G; Kim, Pomy C P; Almeida, Jonatas C; Porto, Wagnner J N; Mota, Rinaldo A

    2017-06-01

    The infection by Neospora caninum in sheep can lead to abortion and the birth of weak and debilitated lambs. The aim of this study was to assess the incidence of natural infection by Neospora caninum and the vertical transmission rate among sheep. A flock of 50 sheep was monitored for serum antibody titres against N. caninum and seroconversion over a period of six months using an indirect ELISA technique. The offspring of the herd was also investigated regarding anti-N. caninum antibodies to determine the vertical transmission rate through the indirect immunofluorescence technique. The initial and final prevalences of infection by N. caninum were 26.0% (13/50) and 72.0% (36/50), respectively, and the incidence of infection by N. caninum in the present study was 62.2% (23/37). The vertical transmission rate found was 15.4% (2/13). A high incidence of infection by N. caninum in sheep was observed, and this is the first report assessing the incidence of N. caninum among naturally infected sheep. Copyright © 2017 Elsevier Ltd. All rights reserved.

  13. Seroprevalence of Neospora caninum in cattle in Sudan

    Directory of Open Access Journals (Sweden)

    Mohammed O. Hussien

    Full Text Available Aim: This cross-sectional survey was conducted to detect anti- N. caninum antibodies in bovine dams' sera samples in nine States of the Sudan. Materials and Methods: Two hundred and seventy six bovine dams' sera samples collected from nine States in the Sudan were screened for anti-Neospora caninum antibodies using a commercial competitive ELISA (cELISA kits. Results: The results showed an overall prevalence rate of 15.9% (range 6.7% - 70% of Neospora caninum antibodies. The prevalence rates were high in White Nile (70% and North Kordofan (30%, moderate in the Northern (15.6%, Red Sea (13.3% States and was low in the South Kordofan (9.4% and River Nile (6.7%. States with high values of percentage inhibition (PI detected in White Nile State compared to other States. No antibodies were detected in El Gadarif, Kassala and South Darfur States. The prevalence was observed to be high in crossbred dams (70% with statistically significant difference (P<0.05 compared to local ecotype (9.3%. However, no correlation was observed between infection rates in two age groups. Conclusion: Neosporosis is prevalent in cattle in most States of Sudan. Absence of evidence of infection in three of the States investigated may reflect the small number of herds and sera tested. [Vet. World 2012; 5(8.000: 465-468

  14. Seroprevalence and Potential Risk Factors Associated with Neospora spp. Infection among Asymptomatic Horses in Jordan.

    Science.gov (United States)

    Talafha, Abdelsalam Q; Abutarbush, Sameeh M; Rutley, David L

    2015-04-01

    This study aimed to determine the seroprevalence and to identify risk factors associated with Neospora spp. infection in horses in Jordan. Management related data were collected from each farm and individual horses. Sera from 227 horses from 5 of 6 climatic regions in Jordan were analyzed for the presence of antibodies to Neospora spp. by ELISA kit. The study was performed during spring of 2010. The association between seropositivity and risk factors was analyzed. A total of 7 (3%) of 227 sera had antibodies for Neospora spp. There was a significant regional difference (P=0.018) between the 5 climatic regions. Positive cases were located in Amman and Irbid, while the other regions (Zarqa, Jordan Valley, and Wadi Mousa) had zero prevalence. The use of anthelmintics at least once a year resulted in a significant reduction of the seroprevalence to Neospora spp. (1.6% vs 9.8%). However, this might be a phenomenon by chance and a better hygiene since owners can invest in anthelmintics. Other risk factors such as age, gender, breed, usage, body condition score, grazing, presence of other animals mixed with the horses in the same property, and a history of previous diseases were not significantly associated with the seroprevalence to Neospora spp. infection. This is the first study to report on the presence of Neospora seropositive horses in Jordan. Further studies are warranted to better understand the role of certain risk factors in the transmission of Neospora spp. among horse population and to determine which Neospora spp. are responsible for the infection.

  15. Secular and seasonal trends of Neospora abortion in California dairy cows.

    Science.gov (United States)

    Thurmond, M C; Anderson, M L; Blanchard, P C

    1995-06-01

    This study was undertaken to determine if the proportion of dairy cow abortions attributable to Neospora sp. infection increased or occurred in a seasonal cycle during a 6-yr period. Abortions caused by Neospora sp. were tallied for all fetuses submitted to the Tulare branch of the California Veterinary Diagnostic Laboratory between January 1985 and December 1990. Regression analysis of 221 cases of Neospora among 762 fetuses submitted showed a weak increasing secular trend (P = 0.053, r2 = 0.05), with predicted monthly proportions at the beginning and end of the 6 yr of 0.16 and 0.33, respectively. Using a Kolmogorov-Smirnov-type statistic, comparison of the 12-mo distribution of Neospora sp. cases and a hypothetical distribution of cows at risk of aborting found about 16% of variation in cases was attributable to season (P fall. Results indicate that Neospora sp. abortion in California dairy cows is not new or recently emerging and that seasonally related factors influence some of the risk of abortion. Results suggest that Neospora sp. has contributed to the high dairy cow abortion rate for many years, and that seasonally varying exposures may predispose to transmission or recrudescence of infection.

  16. Seroprevalence of Neospora Spp. in Horses in North East of Iran

    Directory of Open Access Journals (Sweden)

    MH Hosseini

    2011-06-01

    Full Text Available Background: Neospora caninum, an obligate intracellular protozoan parasite, is recognized as a major cause of abortion in cattle, while limited information is presently available on the seropreva­lence of Neospora antibodies in horses' worldwide .The aim of the present study was to de­termine serologic prevalence of Neospora infection in horses in Iran.Methods: Sera from 150 horses from Mashhad suburb in Razavi Khorasan Province, northeast Iran were examined for antibodies to Neospora spp. using Neospora modified direct agglutina­tion test (N-MAT.Results: Antibodies to this parasite were detected in 45 (30% of the examined serum samples. Thirty four percent of the samples had titer of 1:40 while then reduced to 30% when 1:80 serum dilution was applied as significant cut off titer.Conclusion: This study is the first investigation carried out on the Neospora in horses in Iran and indi­cates that horses in Iran are exposed to this parasite.

  17. Neospora caninum: Biological Relationship with Toxoplasma gondii and its Potential as Zoonosis

    Directory of Open Access Journals (Sweden)

    Laura Robayo-Sánchez

    2017-09-01

    Full Text Available Objective. To carry out a systematic review of the literature on the zoonotic potential of Neospora caninum taking into account its biological relationship with Toxoplasma gondii. Materials and methods. A systematic review was carried out, using two databases for the collection of information (Science direct and Scielo, a search engine (Google Scholar and the National University of Colombia Repository, all documents were organized through the bibliographic manager Mendeley for proper review. Key words like Neosporosis, Neospora caninum, “Toxoplasmosis”, “Toxoplasma gondii”, “Neospora humans”, “Neospora human infection”, “Neospora zoonotic” were used. A total of 8 articles were selected that look for the infection in humans. Results. Eight documents concerning the subject of Neospora in humans were used, whereas these reports show evidence of seropositivity in human samples of anti-N. caninum no studies were found that look for the isolation of the parasite in human tissues (by molecular or in vitro culture. Conclusions. According to the results of these studies, it is not ruled out that the existence of cross-reactions with T. gondii and therefore it should not be ruled out that Neosporosis can behave as a zoonosis. In this regard, more research is required to demonstrate exposure, associated clinical signs, or pathologies related to this infection.

  18. Brazilian donkeys (Equus asinus have a low exposure to Neospora spp.

    Directory of Open Access Journals (Sweden)

    Cynthia Maria Morais de Queiroz Galvão

    Full Text Available Donkeys (Equus asinus are closely related to horses and are known to be infected by several equine pathogens. Neospora caninum and Neospora hughesi are protozoan parasites that infect horses, but they were not confirmed in donkeys up to this date. The aim of this study was to evaluate the exposure of donkeys (Equus asinus to Neospora spp. using tachyzoites of N. caninum as antigen and employing two common serologic methods, IFAT and immunoblot. Sera from 500 donkeys were obtained from 30 municipalities in Bahia state and tested by IFAT. Two of 500 sera were positive for Neospora spp. by IFAT with antibody titers of 100, and recognized a 37kDa antigen in immunoblot. Approximately 22% of the samples showed strong apical reactions and/or incomplete fluorescence, what may cause confusion in the interpretation of IFAT. We concluded that Neospora spp. are possibly of minor importance for Brazilian donkeys. Future studies are necessary to prove that Neospora spp. can naturally infect donkeys.

  19. Brazilian donkeys (Equus asinus) have a low exposure to Neospora spp.

    Science.gov (United States)

    Galvão, Cynthia Maria Morais de Queiroz; Rezende-Gondim, Mariana Marrega; Chaves, Ana Carla Rodrigues; Schares, Gereon; Ribas, Jorge Raimundo Lins; Gondim, Luís Fernando Pita

    2015-01-01

    Donkeys (Equus asinus) are closely related to horses and are known to be infected by several equine pathogens. Neospora caninum and Neospora hughesi are protozoan parasites that infect horses, but they were not confirmed in donkeys up to this date. The aim of this study was to evaluate the exposure of donkeys (Equus asinus) to Neospora spp. using tachyzoites of N. caninum as antigen and employing two common serologic methods, IFAT and immunoblot. Sera from 500 donkeys were obtained from 30 municipalities in Bahia state and tested by IFAT. Two of 500 sera were positive for Neospora spp. by IFAT with antibody titers of 100, and recognized a 37kDa antigen in immunoblot. Approximately 22% of the samples showed strong apical reactions and/or incomplete fluorescence, what may cause confusion in the interpretation of IFAT. We concluded that Neospora spp. are possibly of minor importance for Brazilian donkeys. Future studies are necessary to prove that Neospora spp. can naturally infect donkeys.

  20. Serology based comprehensive study of Neospora infection in domestic animals in Hamedan province, Iran

    Directory of Open Access Journals (Sweden)

    Jamal Gharekhani

    2014-09-01

    Full Text Available This study was conducted to determine seroprevalence of Neospora infection in cattle, sheep, horses, donkeys, and dogs in Hamedan province, Iran. Blood samples (n=2254 from the animals were collected randomly during 2009 to 2012. Sera were prepared from the collected blood samples, which were then examined for the presence of antibodies against Neospora using enzyme-linked immunosorbent assay (ELISA, Neospora modified direct agglutination test (N-MAT, and indirect fluorescent antibody test (IFAT. The seroprevalence rates of Neospora were found as 17.4% (n=245/1406 in cattle, 2.2% (n=8/358 in sheep, 40.8% (n=49/120 in horses, 52% (n=52/100 in donkeys, and 27% (n=73/270 in dogs. In this study, higher levels of Neospora infection were detected in cattle, horses, donkeys, and dogs. This is the first comprehensive study of Neospora infection in domestic animals in Iran. Further researches on molecular and bioassay studies and designing appropriate control strategies against neosporosis in Iran are necessary and strongly recommended.

  1. Survey of Toxoplasma gondii and Neospora caninum, haemotropic mycoplasmas and other arthropod-borne pathogens in cats from Albania

    Science.gov (United States)

    2014-01-01

    Background Albania is a country on the western part of the Balkan Peninsula. The Mediterranean climate is favourable for the stable development of many arthropod species, which are incriminated as vectors for various agents. Recently, several papers have reported on epidemiological aspects of parasitic diseases including vector-borne disease agents of dogs with zoonotic characteristics in Albania. However, data on the epidemiology of feline parasitic and bacterial agents in Albania is scarce. Methods Serum and EDTA-blood samples collected from 146 domestic cats from Tirana during 2008 through 2010 were examined for exposure to Toxoplasma gondii, Neospora caninum, Leishmania infantum, and Anaplasma spp. with IFAT, for infection with L. infantum, A. phagocytophilum, Bartonella spp. and haemotropic mycoplasmas with conventional PCR and real-time PCR and for Dirofilaria immitis with antigen ELISA. Additionally blood smear microscopy was carried out for detection of blood-borne pathogens. Results Antibodies to T. gondii (titre ≥1:100) were demonstrated in 91 cats (62.3%). Antibodies to N. caninum (titre ≥1:100), L. infantum (titre ≥1:64) and Anaplasma spp. (titre ≥1:100) were found in the serum of 15 (10.3%), 1 (0.7%) or 3 (2.1%) cats, respectively. DNA of haemotropic mycoplasmas was detected in the blood of 45 cats (30.8%), namely Candidatus Mycoplasma haemominutum (21.9%), Mycoplasma haemofelis (10.3%), and Candidatus Mycoplasma turicensis (5.5%), with ten cats harbouring co-infections of two mycoplasmas each; blood from one cat was PCR positive for Bartonella henselae. No DNA of Leishmania spp. and A. phagocytophilum or circulating D. immitis antigen was detected in any cat sample. The overall prevalence of haemotropic mycoplasmas was significantly higher in male compared to female cats (40.6% vs. 24.1%, p = 0.0444); and age was associated positively with the prevalence of antibodies to T. gondii (p = 0.0008) and the percentage of haemotropic

  2. Neospora Caninum em canídeos selvagens

    OpenAIRE

    Mattos, Bianca Chaim

    2012-01-01

    Resumo: A neosporose, doença causada pelo protozoário Neospora caninum, está amplamente disseminada em espécies domésticas e selvagens. A preocupação com esta protozoose é principalmente devido ao grande número de abortos em rebanhos bovinos e a doença neurológica, muitas vezes fatal, em cães. O N. caninum possui ciclo heteroxeno e seus hospedeiros definitivos são os cães e os coiotes (Canis latrans). O presente estudo contém uma revisão bibliográfica da neosporose nas principais espécies, co...

  3. Estimated economic losses due to neospora caninum infection in dairy herds with and without a history of neospora caninum associated abortion epidemics

    NARCIS (Netherlands)

    Bartels, C.J.M.; Hogeveen, H.; Schaik, van G.; Wouda, W.; Dijkstra, Th.

    2006-01-01

    In this study, direct economic losses due to Neospora caninum infection, based on actual data from N. caninum seropositive reference herds and from herds that experienced an N. caninum- associated abortion epidemic, were calculated using a stochastic model with random elements. The results

  4. Detection of Leishmania RNA virus in Leishmania parasites.

    Directory of Open Access Journals (Sweden)

    Haroun Zangger

    Full Text Available Patients suffering from cutaneous leishmaniasis (CL caused by New World Leishmania (Viannia species are at high risk of developing mucosal (ML or disseminated cutaneous leishmaniasis (DCL. After the formation of a primary skin lesion at the site of the bite by a Leishmania-infected sand fly, the infection can disseminate to form secondary lesions. This metastatic phenotype causes significant morbidity and is often associated with a hyper-inflammatory immune response leading to the destruction of nasopharyngeal tissues in ML, and appearance of nodules or numerous ulcerated skin lesions in DCL. Recently, we connected this aggressive phenotype to the presence of Leishmania RNA virus (LRV in strains of L. guyanensis, showing that LRV is responsible for elevated parasitaemia, destructive hyper-inflammation and an overall exacerbation of the disease. Further studies of this relationship and the distribution of LRVs in other Leishmania strains and species would benefit from improved methods of viral detection and quantitation, especially ones not dependent on prior knowledge of the viral sequence as LRVs show significant evolutionary divergence.This study reports various techniques, among which, the use of an anti-dsRNA monoclonal antibody (J2 stands out for its specific and quantitative recognition of dsRNA in a sequence-independent fashion. Applications of J2 include immunofluorescence, ELISA and dot blot: techniques complementing an arsenal of other detection tools, such as nucleic acid purification and quantitative real-time-PCR. We evaluate each method as well as demonstrate a successful LRV detection by the J2 antibody in several parasite strains, a freshly isolated patient sample and lesion biopsies of infected mice.We propose that refinements of these methods could be transferred to the field for use as a diagnostic tool in detecting the presence of LRV, and potentially assessing the LRV-related risk of complications in cutaneous leishmaniasis.

  5. Identification of novel proteins in Neospora caninum using an organelle purification and monoclonal antibody approach.

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    Catherine S Sohn

    2011-04-01

    Full Text Available Neospora caninum is an important veterinary pathogen that causes abortion in cattle and neuromuscular disease in dogs. Neospora has also generated substantial interest because it is an extremely close relative of the human pathogen Toxoplasma gondii, yet does not appear to infect humans. While for Toxoplasma there are a wide array of molecular tools and reagents available for experimental investigation, relatively few reagents exist for Neospora. To investigate the unique biological features of this parasite and exploit the recent sequencing of its genome, we have used an organelle isolation and monoclonal antibody approach to identify novel organellar proteins and develop a wide array of probes for subcellular localization. We raised a panel of forty-six monoclonal antibodies that detect proteins from the rhoptries, micronemes, dense granules, inner membrane complex, apicoplast, mitochondrion and parasite surface. A subset of the proteins was identified by immunoprecipitation and mass spectrometry and reveal that we have identified and localized many of the key proteins involved in invasion and host interaction in Neospora. In addition, we identified novel secretory proteins not previously studied in any apicomplexan parasite. Thus, this organellar monoclonal antibody approach not only greatly enhances the tools available for Neospora cell biology, but also identifies novel components of the unique biological characteristics of this important veterinary pathogen.

  6. Identification of Novel Proteins in Neospora caninum Using an Organelle Purification and Monoclonal Antibody Approach

    Science.gov (United States)

    Sohn, Catherine S.; Cheng, Tim T.; Drummond, Michael L.; Peng, Eric D.; Vermont, Sarah J.; Xia, Dong; Cheng, Stephen J.; Wastling, Jonathan M.; Bradley, Peter J.

    2011-01-01

    Neospora caninum is an important veterinary pathogen that causes abortion in cattle and neuromuscular disease in dogs. Neospora has also generated substantial interest because it is an extremely close relative of the human pathogen Toxoplasma gondii, yet does not appear to infect humans. While for Toxoplasma there are a wide array of molecular tools and reagents available for experimental investigation, relatively few reagents exist for Neospora. To investigate the unique biological features of this parasite and exploit the recent sequencing of its genome, we have used an organelle isolation and monoclonal antibody approach to identify novel organellar proteins and develop a wide array of probes for subcellular localization. We raised a panel of forty-six monoclonal antibodies that detect proteins from the rhoptries, micronemes, dense granules, inner membrane complex, apicoplast, mitochondrion and parasite surface. A subset of the proteins was identified by immunoprecipitation and mass spectrometry and reveal that we have identified and localized many of the key proteins involved in invasion and host interaction in Neospora. In addition, we identified novel secretory proteins not previously studied in any apicomplexan parasite. Thus, this organellar monoclonal antibody approach not only greatly enhances the tools available for Neospora cell biology, but also identifies novel components of the unique biological characteristics of this important veterinary pathogen. PMID:21483743

  7. Neospora spp. antibodies in horses from two geographical regions of the state of Santa Catarina, Brazil.

    Science.gov (United States)

    de Moura, Anderson Barbosa; da Silva, Márcio Orides; Farias, Juliana Antunes; Vieira-Neto, Achilles; de Souza, Antonio Pereira; Sartor, Amélia Aparecida; Fonteque, Joandes Henrique; Bunn, Silvério

    2013-01-01

    The aims of this study were to determine occurrences of Neospora spp. IgG antibodies in horses from two geographical regions of the state of Santa Catarina, southern Brazil, and identify risk factors for infection. Analyses were performed on 615 samples using the immunofluorescent antibody test (IFAT ≥ 1:50). Out of the 615 samples, 25 (4.1%) were positive for Neospora spp. The titers for Neospora spp. were distributed as follows: 1:50 (13), 1:100 (eight), 1:200 (three) and 1:400 (one). Out of the 311 samples taken in the mountain region, eight were positive (2.6%). Among the samples from the coastal region (304), 17 had Neospora spp. antibodies, thus indicating occurrence of 5.6%. Although no statistically significant difference was observed (P = 0.06704), the prevalence among animals of the coast was 2.2 times higher than that of the mountain region. Contact with dogs and/or cattle (P = 0.007596) were identified as risk factor for Neospora spp. infection.

  8. Progress towards a Leishmania vaccine.

    Science.gov (United States)

    Tabbara, Khaled S

    2006-07-01

    Leishmaniasis is a vector-born protozoan disease. Approximately 12 million individuals are affected worldwide with an estimated annual incidence of 1.5-2 million. Two clinical manifestations are recognized, cutaneous, and visceral, both of which are common in the Middle East. In both forms, infection is chronic, with potential deformities, persistence following cure, and lifelong risk of reactivation. Attempts to develop an effective human Leishmania vaccine have not yet succeeded. Leishmanization, a crude form of live vaccination historically originated in this part of the world. Experimental vaccination has been extensively studied in model animals in the past 2 decades. In this review, major human killed vaccine trials are surveyed, and modern trends in Leishmania vaccine development, including subunit vaccines, naked DNA vaccines, and transmission blocking vaccines are explored. Recent findings of a link between persistence of live parasites, and maintenance of long-term immunity suggest live vaccination with attenuated strains, as a future vaccination strategy.

  9. Seroprevalence of Neospora infection in horses and donkeys in Hamedan province, Western Iran

    Directory of Open Access Journals (Sweden)

    Jamal Gharekhani

    2013-06-01

    Full Text Available Aim: The aim of the present study was to determine the seroprevalence of Neospora infection in horses and donkeys in Hamedan province, Western Iran.Materials and Methods:In cross-sectional study, Blood samples (n=220 were collected from 120 horses and 100 donkeys in 2012 year. All sera were screened for Neosporausing Neosporamodified direct agglutination test (N-MAT. Results:Antibodies to Neospora infection in horses and donkeys were reported in 40.8% and 52%, respectively. There was not significant correlation demonstrated between infection rates in different age groups and genders.Conclusion: The current study is the first report of Neospora infection in donkeys from Iran. Further investigations and designing control strategies is recommended

  10. Serological reactivity of different antigenic preparations of Leishmania (Leishmania amazonensis and the Leishmania braziliensis complex Reatividade sorológica frente a diferentes preparações antigênicas de Leishmania (Leishmania amazonensis e do complexo Leishmania braziliensis

    Directory of Open Access Journals (Sweden)

    Adriano Gomes-Silva

    2008-04-01

    Full Text Available Total antigen from Leishmania (Leishmania amazonensis and isolates from the Leishmania braziliensis complex, along with their respective antigenic fractions obtained by affinity chromatography on concanavalin-A-Sepharose and jacalin-agarose columns evaluated using immunoenzymatic ELISA assay. For this, serum samples from 229 patients were used, grouped as American tegmental leishmaniasis (nº=58, visceral leishmaniasis (nº=28, Chagas disease (nº=49, malaria (nº=32, tuberculosis (nº=13 and healthy volunteers (nº=49. Samples from American tegmentary leishmaniasis showed higher reactivity with antigens isolated from the Leishmania braziliensis complex than with antigens from Leishmania amazonensis (pAntígeno total de Leishmania (Leishmania amazonensis e isolado do complexo Leishmania brazilienis, assim como suas respectivas frações antigênicas obtidas por cromatografia de afinidade em coluna de concanavalina-A ligada a sepharose e Jacalina ligada a agarose foram avaliadas por ensaio imunoenzimático ELISA. Para tanto, foram utilizadas amostras de soros de 229 pacientes agrupadas em leishmaniose tegumentar americana (nº=58, leishmaniose visceral (nº=28, doença de Chagas (nº=49, malaria (nº=32, tuberculose (nº=13 e voluntários saudáveis (nº=49. Houve maior reatividade das amostras de leishmaniose tegumentar americana com a utilização dos antígenos obtidos do isolado do complexo Leishmania braziliensis quando comparado com antígenos de Leishmania amazonensis (p<0,001. Observou-se ainda que a sensibilidade do teste ELISA variou de 60 a 95% entre os antígenos obtidos do isolado do complexo Leishmania braziliensis. Houve acentuada reatividade inespecífica das amostras de soros com a utilização das frações antigênicas ligantes de Concanavalina-A e Jacalina de ambos os complexos Leishmania em comparação aos demais antígenos (p<0,001. Os resultados apresentados no presente trabalho sugerem que a utilização de antígenos hom

  11. leishmania major-phlebotomus duboscqi interactions

    African Journals Online (AJOL)

    hi-tech

    2004-02-01

    Feb 1, 2004 ... Leishmaniasis is a vector-borne disease in which. Leishmania parasites are transmitted by the bite of phlebotomine sand flies. In the vertebrate host,. Leishmania parasites survive and multiply intracellularly in mononuclear phagocytes as a flagellated amastigotes, about 2 to 54 µm in diameter. These cells ...

  12. Seroprevalence of Toxoplasma gondii and Neospora spp. Infections in Arab Horses, Southwest of Iran

    Science.gov (United States)

    Tavalla, Mehdi; Sabaghan, Mohammad; Abdizadeh, Rahman; Khademvatan, Shahram; Rafiei, Abdollah; Razavi Piranshahi, Anahita

    2015-01-01

    Background: Because of the economic importance of the Arab race horses and also the role of Toxoplasma gondii and Neospora spp. in abortion and reproductive failure of these animals, we decided to perform this study. Objectives: We designed this study to investigate the seroprevalence of anti-Toxoplasma gondii and anti-Neospora spp. antibodies in Arab horses from 12 cities of Khuzestan province in southwest of Iran. Materials and Methods: From October 2009 to March 2011, a total of 235 blood samples were collected from jugular veins of Arab horses of different ages and genders from 12 cities of Khuzestan province. All the sera were tested for anti-Toxoplasma antibodies using the modified agglutination test (MAT) and the existence of anti-Neospora antibodies were tested using N-MAT for Neospora spp. Results: According to the MAT results, antibodies to T. gondii were found in 114 (48.5%) of 235 sera with titers of 1:20 in 84, 1:40 in 19, 1:80 in four, 1:160 in four, and 1:320 in three horses. According to the N-MAT results, antibodies to Neospora spp. were found in 47 (20%) of 235 sera with titers of 1:40 in 39, 1:80 in five, and 1:160 in three horses. We did not observe any statistically significant differences regarding age groups and genders between seropositive and seronegative horses for Neospora spp. using chi-square (χ2) test, but it seemed that anti-Toxoplasma antibodies were more prevalent in older horses (≥ 10 years old). Conclusions: The results indicated that Arab horses are exposed to these parasites in southwest of Iran. Further research is required to determine the genomic structures of these parasites in Arab horses in southwest of Iran. PMID:25834714

  13. Plasmodium ovale in Indonesia.

    Science.gov (United States)

    Baird, J K; Purnomo; Masbar, S

    1990-12-01

    We report 34 infections by Plasmodium ovale found among 15,806 blood film examinations taken between 1973 and 1989 from several sites in Indonesia. Twenty five of the P. ovale infections occurred in a single sample of 514 people living in Owi, Irian Jaya. We detected five additional infections at 3 other sites in Irian Jaya. Other infections by P. ovale occurred at two sites in West Flores. Another infection has already been reported from East Timor. Despite relatively frequent sampling of populations on Sumatra, Kalimantan, Java and Sulawesi, P. ovale has not been found on those islands. It appears that this parasite occurs only on the easternmost islands of the Indonesian archipelago where it is nonetheless a rare finding.

  14. Characterization of Leishmania (Leishmania) amazonensis promastigotes resistant to pentamidine.

    Science.gov (United States)

    Coelho, Adriano C; Gentil, Luciana G; da Silveira, José Franco; Cotrim, Paulo C

    2008-09-01

    Pentamidine is a second-line agent used in the treatment of leishmaniasis and its mode of action and mechanism of resistance is not well understood. It was previously demonstrated that transfection of promastigotes and amastigotes with the ABC transporter PRP1 gene confers resistance to pentamidine. To further clarify this point, we generated Leishmania amazonensis mutants resistant to pentamidine. Our results indicated that this ABC transporter is not associated with pentamidine resistance in lines generated by drug pressure through amplification or overexpression mechanisms of PRP1 gene.

  15. Seroprevalence rates of antibodies againstLeishmania infantum and other protozoan and rickettsial parasites in dogs

    Directory of Open Access Journals (Sweden)

    Silvana de Cássia Paulan

    Full Text Available Canine visceral leishmaniasis (CVL is caused by the protozoan Leishmania infantum, which infects dogs and humans in many regions of Brazil. The present study involved an indirect fluorescent antibody test (IFAT to analyze L. infantum,Ehrlichia spp., Babesia canis,Toxoplasma gondii and Neospora caninuminfection rates in serum samples from 93 dogs in a rural settlement in Ilha Solteira, SP, Brazil. The seroprevalence rates of anti-L. infantum, anti-Ehrlichia, anti-B. canis, anti-T. gondii and anti-N. caninum antibodies were 37.6%, 75.3%, 72%, 47.3% and 6.4%, respectively. In addition to IFAT, direct microscopic examination of popliteal lymph node aspirates revealed 26.9% of CVL positive dogs. Serological tests revealed that 17.2% of the dogs were seropositive for a single parasite, 29% for two parasites, 33% for three, 16.1% for four, and 1.1% for five parasites, while 3.2% were seronegative for five parasites. The presence of antibodies against these parasites in serum samples from dogs confirmed their exposure to these parasites in this rural area. Because of the potential zoonotic risk of these diseases, mainly leishmaniasis, ehrlichiosis and toxoplasmosis, special attention should focus on programs for the improvement of diagnostic assays and control measures against these parasites.

  16. Susceptibility of various cell lines to Neospora caninum tachyzoites cultivation

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    Khordadmehr, M.,

    2014-05-01

    Full Text Available Neospora caninum is a coccidian protozoan parasite which is a major cause of bovine abortions and neonatal mortality in cattle, sheep, goat and horse. Occasionally, cultured cells are used for isolation and multiplication of the agent in vitro with several purposes. In this study the tachyzoite yields of N. caninum were compared in various cell cultures as the host cell lines. Among the cell cultures tested, two presented good susceptibility to the agent: cell lines Vero and MA-104. SW742 and TLI (in vitro suspension culture of lymphoid cells infected with Theileria lestoquardi showed moderate sensitivity. No viable tachyzoite were detected in the culture of MDCK and McCoy cell lines. These results demonstrate that MA-104 and SW742 cells present adequate susceptibility to N. caninum compared to Vero cells, which have been largely used to multiply the parasite in vitro. Moreover, these have easy manipulation, fast multiplication and relatively low nutritional requirements. In addition, the result of this study showed that TLI cell line as a suspension cell culture is susceptible to Nc-1 tachyzoites infection and could be used as an alternative host cell line for tachyzoites culture in vitro studies.

  17. Genetic diversity of bovine Neospora caninum determined by microsatellite markers.

    Science.gov (United States)

    Salehi, N; Gottstein, B; Haddadzadeh, H R

    2015-10-01

    Neospora caninum is one of the most significant parasitic organisms causing bovine abortion worldwide. Despite the economic impact of this infection, relatively little is known about the genetic diversity of this parasite. In this study, using Nc5 and ITS1 nested PCR, N. caninum has been detected in 12 brain samples of aborted fetuses from 298 seropositive dairy cattle collected from four different regions in Tehran, Iran. These specimen (Nc-Iran) were genotyped in multilocus using 9 different microsatellite markers previously described (MS4, MS5, MS6A, MS6B, MS7, MS8, MS10, MS12 and MS21). Microsatellite amplification was completely feasible in 2 samples, semi-completely in 8 samples, and failed in 2 samples. Within the two completely performed allelic profiles of Nc-Iran strains, unique multilocus profiles were obtained for both and novel allelic patterns were found in the MS8 and MS10 microsatellite markers. The Jaccard's similarity index showed significant difference between these two strains and from other standard isolates derived from GenBank such as Nc-Liv, Nc-SweB1, Nc-GER1, KBA1, and KBA2. All samples originating from the same area showed identical allelic numbers and a correlation between the number of repeats and geographic districts was observed. Copyright © 2015 Elsevier Ireland Ltd. All rights reserved.

  18. A review of Neospora caninum in water buffalo (Bubalus bubalis).

    Science.gov (United States)

    Reichel, Michael P; McAllister, Milton M; Nasir, Amar; Moore, Dadin P

    2015-09-15

    A number of countries in the world have reported infections with Neospora caninum in water buffalo (Bubalus bubalis), from Africa to Asia, Europe and South America and recently Australia. In general, clinical manifestations (such as abortion) seem rare, which has raised the prospect that buffalo may be inherently resistant to clinical effects of N. caninum infection. Worldwide, the seroprevalence of N. caninum infection (as a measure of exposure determined by the detection of antibody) in buffalo is high, at approximately 48%. This reported seroprevalence is three or four times higher than that reported from the world's cattle populations, which have collective seroprevalence rates of 16.1% for dairy cattle and 11.5% for beef cattle. However, there is a lack of standardisation in seroprevalence studies and some studies may well under-estimate the true level of infection. Epidemiologic evidence supports post-natal transmission, and in utero transmission has also been demonstrated. The causes for water buffalo to have markedly higher seroprevalence but apparently lower neosporosis abortion rates than cattle warrant further investigation. Copyright © 2015 Elsevier B.V. All rights reserved.

  19. Neospora caninum prevalence in dogs raised under different living conditions.

    Science.gov (United States)

    Nazir, Muhammad Mudasser; Maqbool, Azhar; Akhtar, Masood; Ayaz, Mazhar; Ahmad, Atif Nisar; Ashraf, Kamran; Ali, Asif; Alam, Muhammad Azhar; Ali, Muhammad Amjad; Khalid, Abdur Rauf; Lindsay, David S

    2014-08-29

    Neospora caninum is an important cause of abortion in dairy cattle worldwide. Dogs are important in the epidemiology of N. caninum because they act as definitive hosts shedding oocysts in the environment. Vertical transmission of the parasite is well recognized as an important aspect of the epidemiology of the parasite but the importance of horizontal transmission has been less studied. A N. caninum competitive ELISA was used to examine serum samples from 600 dogs that were raised under 4 different living conditions. Samples from 138 dogs living on 24 dairies with a prevalence (0-70%) of anti-N. caninum antibodies in the cattle, 294 pet dogs without neurological signs, 76 from pet dogs exhibiting neurological signs, and 92 stray dogs were examined. The overall seroprevalence of N. caninum was 23.5% (95% CI = ± 2.99) in the 600 dogs. Significant (P 0.05). The prevalence of N. caninum antibodies was not significantly (P>0.05) different in dogs based on breed. These findings suggest a relationship between N. caninum infection of dogs from dairies and cattle on these dairies. However, further research is required to determine what is the most important way dogs acquire infection and how to prevent dogs from shedding oocysts. Copyright © 2014 Elsevier B.V. All rights reserved.

  20. Activity of several kinds of drugs against Neospora caninum.

    Science.gov (United States)

    Qian, Weifeng; Wang, Hui; Shan, Dan; Li, Bo; Liu, Jing; Liu, Qun

    2015-12-01

    Neosporosis caused by Neospora caninum is a serious disease in cattle and dogs worldwide. It is the major cause of abortion and neonatal mortality in cattle. In this study, we evaluated the anti-N. caninum activity of Chinese medicine extracts (curcumin, artemether), herbicides (atrazine, glyphosate), anticoccidiosis drugs (toltrazuril and ponazuril), cyclophosphamide, diminazene aceturate and praziquantel in vitro using parasite growth, replication and host cell invasion assays in human foreskin fibroblast cultures. Curcumin, artemether, atrazine, toltrazuril and ponazuril exhibited inhibitory activity with 50% growth inhibitory concentration (IC50) of 1.1±0.4, 1.0±0.05, 11.2±2.7, 30.3±2.0 and 33.3±4.1μg/ml, respectively, in the growth inhibition assay. They were also active against protozoa replication, but only curcumin was effective against host cell invasion. Glyphosate, cyclophosphamide, diminazene aceturate and praziquantel were ineffective. In an in vivo infection model, curcumin showed no activity against N. caninum infection. We showed that curcumin, artemether, atrazine, toltrazuril, and ponazuril exhibited anti-N. caninum activity in vitro, providing important information for further studies on anti-N. caninum drugs. Copyright © 2015. Published by Elsevier Ireland Ltd.

  1. Neospora caninum abortion in a Malayan tapir (Tapirus indicus).

    Science.gov (United States)

    Peters, M; Osmann, C; Wohlsein, P; Schares, G

    2017-05-30

    A captive 17-year old female Malayan tapir (Tapirus indicus) aborted a fetus with a crown rump length of 19cm in early pregnancy. The fetus showed an early state of mummification. Histologically, a multifocal mononuclear encephalitis, myocarditis and periportal hepatitis was present indicating a possible protozoal cause of abortion. Although immunohistologically, Neospora (N.) caninum antigen could not be demonstrated, N. caninum DNA was detected by Polymerase Chain Reaction (PCR) in brain, heart, liver and lung of the fetus. N. caninum DNA was extracted from the aborted fetus and the microsatellite marker MS10 was amplified by PCR and sequenced. The obtained MS10 microsatellite pattern has not been described in Germany yet. Nevertheless, the MS10 pattern was very similar to those reported for N. caninum isolated from dogs and cattle in Germany. Because of the histological pattern and extent of the lesions, neosporosis was suspected as the cause of fetal death and abortion. This case report describes for the first time transplacental transmission of N. caninum and abortion due to neosporosis in a tapir. Copyright © 2017 Elsevier B.V. All rights reserved.

  2. Oral infection of neonate gerbils by Neospora caninum tachyzoites

    Directory of Open Access Journals (Sweden)

    Maiara Sanitá Tafner Ferreira

    2015-01-01

    Full Text Available ABSTRACT: Neosporosis is a parasitic disease caused by the protozoan Neospora caninum which results in major economic losses for cattle breeding due to abortion and other reproductive disorders. Gerbils (Meriones unguiculatus are commonly used as experimental models for neosporosis due to their high susceptibility to N. caninum infection, both by oocysts ingestion as by tachyzoites/bradyzoites parenteral inoculation. However, the risk of transmission by tachyzoites ingestion is not fully elucidated. In this study, infection of neonate gerbils by N. caninum (NC-1 strain tachyzoites inoculated by the oral route and the parasite distribution in gerbils' tissues were evaluated by protozoan DNA detection. Seventeen neonate gerbils, aged 4-5 days, were inoculated with 4x105 tachyzoites by the oral route and one gerbil was kept as uninfected control. N. caninum DNA was detected in 100% of the inoculated gerbils, showing that the oral route is effective as a potential route of infection of neonates by N. caninum tachyzoites. N. caninum DNA was reported in all organs evaluated (heart, lungs, kidneys, liver, spleen and brain, with different frequencies. These results showed systemically distributed infection of neonate gerbils after oral inoculation of tachyzoites.

  3. Caprine Monocytes Release Extracellular Traps against Neospora caninum In Vitro

    Directory of Open Access Journals (Sweden)

    Zhengtao Yang

    2018-01-01

    Full Text Available Neospora caninum is an obligate intracellular apicomplexan parasite that causes reproductive loss and severe economic losses in dairy and goat industry. In the present study, we aim to investigate the effects of N. caninum tachyzoites on the release of extracellular traps (ETs in caprine monocytes and furthermore elucidated parts of its molecular mechanisms. N. caninum tachyzoite-induced monocytes-derived ETs formation was detected by scanning electron microscopy. H3 and myeloperoxidase (MPO within monocyte-ETs structures were examined using laser scanning confocal microscopy analyses. The results showed that N. caninum tachyzoites were not only able to trigger ETs formation in caprine monocytes, but also that monocyte-released ETs were capable of entrapping viable tachyzoites. Histones and MPO were found to be decorating the DNA within the monocytes derived-ETs structures thus proving the classical components of ETs. Furthermore, inhibitors of NADPH oxidase-, MPO-, ERK 1/2-, or p38 MAPK-signaling pathway significantly decreased N. caninum tachyzoite-triggered caprine monocyte-derived ETosis. This is the first report of ETs release extruded from caprine monocytes after N. caninum exposure and thus showing that this early innate immune effector mechanism might be relevant during the acute phase of caprine neosporosis.

  4. Neospora caninum and Bovine Neosporosis: Current Vaccine Research.

    Science.gov (United States)

    Marugan-Hernandez, V

    Neospora caninum, a tissue cyst-forming parasite, is the causative agent of bovine neosporosis. It is considered to be one of the most important transmissible causes of reproductive failure in cattle; abortion and neonatal mortality result in significant economic losses within the cattle industry worldwide. The balance between acute (mediated by the tachyzoite stage) and persistent (mediated by the bradyzoite stage) phases of the infection is influenced by the immune status of the animal, and for pregnant cows (the intermediate host) immune status is critical for transplacental (i.e. vertical) transmission of the parasite and associated disease outcomes. The horizontal route of transmission from the definitive host, the dog, occurs via ingestion of oocysts containing sporozoites, and plays a minor but important role in transmission of the infection to cattle. Despite the importance of this disease, there is no vaccine or treatment available currently, and at the present the only control measure to reduce the impact of disease is informed management on the farm. The development of vaccines, targeting key biological processes such as invasion and persistent infection, is needed urgently for the control of this widespread parasite. Copyright © 2017 Elsevier Ltd. All rights reserved.

  5. Dog shedding oocysts of Neospora caninum: PCR diagnosis and molecular phylogenetic approach

    Czech Academy of Sciences Publication Activity Database

    Šlapeta, Jan Roger; Modrý, David; Kyselová, Iveta; Hořejš, R.; Lukeš, Julius; Koudela, Břetislav

    2002-01-01

    Roč. 109, 3-4 (2002), s. 157-167 ISSN 0304-4017 Institutional research plan: CEZ:AV0Z6022909 Keywords : Neospora * Hammondia * Toxoplasma Subject RIV: GE - Plant Breeding Impact factor: 1.473, year: 2002

  6. Red foxes (Vulpes vulpes) in Romania are carriers of Toxoplasma gondii but not Neospora caninum.

    Science.gov (United States)

    Şuteu, Ovidiu; Mihalca, Andrei Daniel; Paştiu, Anamaria Ioana; Györke, Adriana; Matei, Ioana Adriana; Ionică, Angela; Balea, Anamaria; Oltean, Miruna; D'Amico, Gianluca; Sikó, Sándor Barabási; Ionescu, Dan; Gherman, Călin Mircea; Cozma, Vasile

    2014-07-01

    Brain samples from 182 red foxes (Vulpes vulpes) from Romania were examined using a standard PCR technique. Results provide evidence of Toxoplasma gondii (11 foxes=6.0%) and Neospora caninum (1 fox=0.5%) DNA in red foxes from Romania. No coinfections were found.

  7. Seroprevalence of Neospora caninum in aborting dairy cattle in the Czech Republic

    Czech Academy of Sciences Publication Activity Database

    Václavek, P.; Koudela, Břetislav; Modrý, David; Sedlák, K.

    2003-01-01

    Roč. 115, č. 3 (2003), s. 239-245 ISSN 0304-4017 Institutional research plan: CEZ:AV0Z6022909 Keywords : Neospora caninum * abortion * cattle Subject RIV: GJ - Animal Vermins ; Diseases, Veterinary Medicine Impact factor: 1.583, year: 2003

  8. Comparison of the IFAT and Iscom-ELISA response in bovine foetuses with Neospora caninum infection

    DEFF Research Database (Denmark)

    Slotved, H.C.; Jensen, L.; Lind, Peter

    1999-01-01

    The study was carried out to evaluate the efficacy of foetal serology in the diagnosis of Neospora-associated bovine abortions. Fluids from 14 foetuses of cows with confirmed neosporosis (Group A), seven foetuses with confirmed bovine viral diarrhoea virus (BVD infection) (Group B) and 11 aborted...... Society for Parasitology Inc. Published by Elsevier Science Ltd. All rights reserved....

  9. Histopathological and molecular study of Neospora caninum infection in bovine aborted fetuses

    Directory of Open Access Journals (Sweden)

    Amir Kamali

    2014-12-01

    Conclusions: The results showed N. caninum infection was detected in high percentage of aborted fetuses. In addition, at least one fourth of abortions caused by Neospora infection. These results indicate increasing number of abortions associated with the protozoa more than reported before in Iran.

  10. Neospora caninum surface antigen (p40) is a potential diagnostic marker for cattle neosporosis

    Science.gov (United States)

    Neospora caninum is an intracellular protozoan that infects domestic and wild canids as well as many warm-blooded animals as shown by the isolation of viable parasites. The effectiveness of diagnostic tests for detecting specific antibodies against N. caninum is hampered by potential cross-reaction ...

  11. Seroprevalence and spatial distribution of Neospora caninum in a population of beef cattle

    NARCIS (Netherlands)

    Loobuyck, M.; Frössling, J.; Lindberg, A.; Björkman, C.

    2009-01-01

    A cross-sectional serological survey for Neospora caninum was carried out in Swedish beef cattle in order to estimate the seroprevalence and investigate any geographical patterns of the infection. Blood samples were collected from 2754 animals in 2130 herds and analysed for presence of antibodies to

  12. Fetal death in cows experimentally infected with Neospora caninum at 110 days of gestation

    Science.gov (United States)

    Neospora caninum is a major cause of abortion in cattle, but the reasons why some animals abort and not others remain unclear. Most of the N. caninum experimental primary infections in cattle late in gestation, after 120 days of pregnancy, results in birth of full-term congenitally infected fetuses....

  13. Prevalence of antibodies to Sarcocystis neurona and Neospora hughesi in horses from Mexico

    Science.gov (United States)

    The risk of equine protozoal myeloencephalitis (EPM) to horses in Mexico has not been established. Serum samples from 495 horses in Durango State, Mexico were examined for the presence of antibodies to Sarcocystis neurona and Neospora hughesi using enzyme-linked immunosorbent assays (ELISAs) based o...

  14. Gene expression profiling of a temperature-sensitive strain of Neospora caninum

    Science.gov (United States)

    To understand the genetic basis of virulence, gene expression profiles of a temperature-sensitive clone (NCts-8, relatively avirulent) and its wild type (NC-1) of Neospora caninum were characterized and compared using a high-density microarray with approximately 63,000 distinct oligonucleotides. Thi...

  15. Seroprevalence of Toxoplasma gondii and Neospora caninum in north-eastern Atlantic Harbor seal

    Science.gov (United States)

    Antibodies to Toxoplasma gondii and Neospora caninum were determined in serum samples from 47 grey seals (Halichoerus grypus) and 56 harbor seals (Phoca vitulina vitulina) from the Atlantic coasts of United Kingdom and France. Antibodies to T. gondii assayed by the modified agglutination test (MAT) ...

  16. Detection of antibodies against Sarcocystis neurona, neospora spp., and Toxoplasma gondii in horses from Costa Rica

    Science.gov (United States)

    Serum samples from 315 horses from Costa Rica, Central America were examined for the presence of antibodies against Sarcocystis neurona, Neospora spp., and Toxoplasma gondii using the SnSAG2 ELISA, the NhSAG1 ELISA, and the modified agglutination test, respectively. Anti-S. neurona antibodies were f...

  17. Congenital transmission of Neospora caninum in white tailed deer (Odocoileus virginianus)

    Science.gov (United States)

    Neosporosis is an important cause of bovine abortion worldwide. Many aspects of transmission of Neospora caninum in nature are unknown. The white-tailed deer (Odocoileus virginianus) is considered one of the most important wildlife reservoirs of N. caninum in the USA. During the hunting seasons of 2...

  18. Seroepidemiology of Sarcocystis neurona and Neospora hughesi infections in domestic donkeys (Equus asinus) in Durango, Mexico

    Science.gov (United States)

    The protozoans Sarcocystis neurona and Neospora spp. cause clinical disease in horses. There is currently no information regarding S. neurona and N. hughesi infections in donkeys in Mexico. Here, we determined the presence of antibodies against S. neurona and N. hughesi in donkeys in the northern Me...

  19. Seroprevalence of Neospora caninum in free-range chickens (Gallus domesticus) from the Americas

    Science.gov (United States)

    Neospora caninum and Toxoplasma gondii are biologically and morphologically similar coccidians with canids as definitive hosts for N.caninum and felids for T. gondii. Feral chickens have been used as indicators of soil contamination with T. gondii oocysts because they feed from ground. In the presen...

  20. Isolation of viable neospora caninum from brains of wild gray wolves (canis lupus)

    Science.gov (United States)

    Neospora caninum is a common cause of abortion in cattle worldwide. Canids, including the dog and the dingo (Canis familiaris), the coyote (Canis latrans), and the gray wolf (Canis lupus) are its definitive hosts, but also can act as intermediate hosts by harbor tissue stages of the parasite that ca...

  1. Associations of Neospora caninum seropositivity with gestation number and pregnancy outcome in Danish dairy herds

    DEFF Research Database (Denmark)

    Jensen, Anette Møllegaard; Bjorkman, C.; Kjeldsen, A.M.

    1999-01-01

    The prevalence and distribution of seropositivity towards the protozoan parasite Neospora caninum were studied in single blood samples from 1561 cows from 31 Danish dairy herds. Blood samples were analysed by an indirect enzyme-linked immunoassay and an indirect fluorescent-antibody test, Seropre...

  2. Leishmania metacaspase: an arginine-specific peptidase.

    Science.gov (United States)

    Martin, Ricardo; Gonzalez, Iveth; Fasel, Nicolas

    2014-01-01

    The purpose of this chapter is to give insights into metacaspase of Leishmania protozoan parasites as arginine-specific cysteine peptidase. The physiological role of metacaspase in Leishmania is still a matter of debate, whereas its peptidase enzymatic activity has been well characterized. Among the different possible expression systems, metacaspase-deficient yeast cells (Δyca1) have been instrumental in studying the activity of Leishmania major metacaspase (LmjMCA). Here, we describe techniques for purification of LmjMCA and its activity measurement, providing a platform for further identification of LmjMCA substrates.

  3. Kinetics of anti-Neospora antibodies during the period of two consecutive pregnancies in chronically infected dairy cows.

    Science.gov (United States)

    Špilovská, Silvia; Moskwa, Bożena; Reiterová, Katarina

    2013-12-01

    The course of anti-Neospora antibody kinetics during two consecutive pregnancies has been evaluated in five chronically infected dairy cows. The blood samples of cows were collected monthly. Anti-Neospora antibodies in blood sera were detected by indirect ELISA (ID-VET, France). During whole period of the study cows remained seropositive; with S/P% values (iELISA) ranging from 94 to 214%. The antibody kinetics determined by iELISA showed a significant increase (PNeospora from mothers to offspring in the herd, dam-daughter serology was performed. Anti-Neospora antibodies was found in 4 from 6 heifers (>6 months old). Study presents original data reporting on the very similar persistent pattern of anti-Neospora antibody levels during the third trimester of pregnancies in all five dairies. Based on the high seropositivity of female offspring, the reactivation of a latent infection of cows rather than a re-infection can be supposed.

  4. Characterization of Neospora caninum macrophage migration inhibitory factor.

    Science.gov (United States)

    Qu, Guanggang; Fetterer, Raymond; Jenkins, Mark; Leng, Lin; Shen, Zhiqiang; Murphy, Charles; Han, Wenyu; Bucala, Richard; Tuo, Wenbin

    2013-10-01

    The present study is the first characterization of Neospora caninum macrophage migration inhibitory factor (NcMIF). BLAST-N analysis of NcMIF revealed high similarity (87%) to the Toxoplasma gondii MIF. NcMIF was cloned and expressed in Escherichia coli in 3 forms, NcMIF (mature protein), NcMIFm (mutation of proline-2 to glycine), and NcMIFhis (addition of a polyhistidine tag at the N-terminus). None of these recombinant NcMIFs (rNcMIF) had tautomerase, oxidoreductase, or immunologic regulatory activities. rNcMIF was unable to compete with recombinant human MIF for a MIF receptor (CD74), suggesting that NcMIF does not bind to this MIF receptor. The glycine substitution for proline-2 of NcMIF resulted in increased retention time on SEC-HPLC and decreased formation of dimers and trimers. The addition of N-terminal HIS-tag led to increased formation of trimers. Immunofluorescence staining demonstrated that NcMIF was localized to the apical end of N. caninum tachyzoites. Immunoelectron microscopy further revealed that NcMIF was present in the micronemes, rhoptries, dense granules, and nuclei. NcMIF was abundant in the tachyzoite lysate and present in excretory and secretory antigen (ESAg) preparations. Total and secretory NcMIF was more abundant in a non-pathologic clone, Ncts-8, than in the wild type isolate (NC1). Furthermore, NcMIF release by the both isolates was increased in the presence of calcium ionophore. This differential production of NcMIF by the pathologic and non-pathologic isolates of N. caninum may suggest a critical role of this molecule in the infectious pathogenesis of this parasite. Published by Elsevier Inc.

  5. Effects of Thai piperaceae plant extracts on Neospora caninum infection.

    Science.gov (United States)

    Leesombun, Arpron; Boonmasawai, Sookruetai; Nishikawa, Yoshifumi

    2017-06-01

    Neosporosis has a worldwide distribution and causes economic losses in farming, particularly by increasing the risk of abortion in cattle. This study investigated the effects of Thai piperaceae (Piper betle, P. nigrum, and P. sarmentosum) extracts on Neospora caninum infections in vitro and in vivo. In an in vitro parasite growth assay based on the green fluorescent protein (GFP) signal, P. betle was the most effective extract at inhibiting parasite growth in human foreskin fibroblast cells (IC 50 of GFP-expressing N. caninum parasites, 22.1μg/ml). The P. betle extract, at 25μg per ml, inhibited parasite invasion into host cells. Furthermore, in two independent experiments, treating N. caninum-infected mice with the P. betle extract for 7days post-infection increased their survival. In trial one, the anti-N. caninum effects of the P. betle extract reduced the mouse clinical scores for 30days post-infection (dpi). The survival rate of the mice treated with 400mg/kg was 100% compared with 66.6% for those treated with 100mg/kg and the non-treated controls. In trial two, treating the infected mice with the P. betle extract increased their survival at 50dpi. All mice in the non-treatment group died; however, the survival rates of the 400mg/kg-treated and 100mg/kg-treated mice were 83.3% and 33.3%, respectively. Also, a trend towards a reduced parasite burden was noted in the brains of the P. betle extract-treated mice, compared with the control mice. Therefore P. betle extract has potential as a medicinal plant for treating neosporosis. Copyright © 2017 Elsevier B.V. All rights reserved.

  6. Seroprevalence and risk factors of Neospora spp. and Toxoplasma gondii infections among horses and donkeys in Nigeria, West Africa.

    Science.gov (United States)

    Bártová, Eva; Sedlák, Kamil; Kobédová, Kateřina; Budíková, Marie; Joel Atuman, Yakubu; Kamani, Joshua

    2017-09-26

    Neospora spp. and Toxoplasma gondii are considered to be a globally distributed parasites affecting wide range of warm-blooded animals. Neosporosis has caused clinical illness in horses and consumption of horse meat has been epidemiologically linked to clinical toxoplasmosis in humans. This study was conducted to determine Neospora spp. and T. gondii antibodies and risk factors of infection in horses and donkeys from three states of Nigeria. A total of 144 samples were collected from clinically healthy animals (120 horses and 24 donkeys). The sera were tested for antibodies to Neospora spp. and T. gondii by indirect fluorescence antibody test, a titer ≥ 50 was considered positive. Seroprevalence data were statistically analyzed, considering the variables of gender, age, use, state, origin of breed and type of management. Antibodies to Neospora spp. and T. gondii were detected in 8% horses with titers 50 and in 24% horses with titers 50-800, respectively. Co-infection of both parasites was proved in three horses (3%). Statistical differences were found only for T. gondii seroprevalence in horses with different use, locality, origin and management (p-value ≤ 0.05). Antibodies to T. gondii were detected in four (17%) of 24 donkeys with statistical difference (p-value ≤ 0.05) in animals of different use; antibodies to Neospora spp. were not proved in any of the donkeys. This is the first seroprevalence study of Neospora spp. and T. gondii in equids from Nigeria.

  7. Plasmodium vivax: who cares?

    Directory of Open Access Journals (Sweden)

    Barnwell John W

    2008-12-01

    Full Text Available Abstract More attention is being focused on malaria today than any time since the world's last efforts to achieve eradication over 40 years ago. The global community is now discussing strategies aimed at dramatically reducing malarial disease burden and the eventual eradication of all types of malaria, everywhere. As a consequence, Plasmodium vivax, which has long been neglected and mistakenly considered inconsequential, is now entering into the strategic debates taking place on malaria epidemiology and control, drug resistance, pathogenesis and vaccines. Thus, contrary to the past, the malaria research community is becoming more aware and concerned about the widespread spectrum of illness and death caused by up to a couple of hundred million cases of vivax malaria each year. This review brings these issues to light and provides an overview of P. vivax vaccine development, then and now. Progress had been slow, given inherent research challenges and minimal support in the past, but prospects are looking better for making headway in the next few years. P. vivax, known to invade the youngest red blood cells, the reticulocytes, presents a strong challenge towards developing a reliable long-term culture system to facilitate needed research. The P. vivax genome was published recently, and vivax researchers now need to coordinate efforts to discover new vaccine candidates, establish new vaccine approaches, capitalize on non-human primate models for testing, and investigate the unique biological features of P. vivax, including the elusive P. vivax hypnozoites. Comparative studies on both P. falciparum and P. vivax in many areas of research will be essential to eradicate malaria. And to this end, the education and training of future generations of dedicated "malariologists" to advance our knowledge, understanding and the development of new interventions against each of the malaria species infecting humans also will be essential.

  8. Antibodies and Plasmodium falciparum merozoites

    NARCIS (Netherlands)

    Ramasamy, R; Ramasamy, M; Yasawardena, S

    There is considerable interest in using merozoite proteins in a vaccine against falciparum malaria. Observations that antibodies to merozoite surface proteins block invasion are a basis for optimism. This article draws attention to important and varied aspects of how antibodies to Plasmodium

  9. Potential involvement of Neospora caninum in naturally occurring ovine abortions in New Zealand.

    Science.gov (United States)

    Howe, L; Collett, M G; Pattison, R S; Marshall, J; West, D M; Pomroy, W E

    2012-04-30

    Neospora caninum is an obligate intracellular parasite and is recognised as the leading cause of bovine abortion worldwide. Natural infection with N. caninum has been described in sheep but it has generally not been regarded as a significant cause of abortion. Recently, there have been several New Zealand cases of foetal abortions where N. caninum was detected which strongly suggested the involvement of Neospora in these abortions. However, there is minimal information about the prevalence of N. caninum infection naturally occurring in New Zealand sheep flocks and particularly its impact on reproduction success. Thus, this present study provides preliminary data on the role that Neospora is playing in ovine reproductive failure by establishing the prevalence of N. caninum antibodies and DNA in ewe blood and foetal material present in 21 New Zealand sheep farms with ongoing unexplained abortion problems and 10 farms with consistently high fertility levels. The results of this study demonstrated an overall seroprevalence of 1.4% which varied between Aborting/non-pregnant (1.8%), age-matched pregnant controls (0.6%) and high fertility (2.1%) ewes. However, despite the variation observed, there was no statistical difference between the three groups. In addition, Neospora DNA was detected by PCR in 13% of submitted foetal brains and in ewe blood from aborting/non-pregnant (6.9%), age-matched pregnant controls (3.6%) and high fertility pregnant (2.1%) ewes. When the PCR results were considered with the IFAT and IDEXX ELISA results, there was no correlation between serology positive and PCR positive blood samples. Taken together, these results reveal that reliance on ELISA-based serology or PCR alone may underestimate the involvement of Neospora. Furthermore, determining the involvement of Neospora appears to require a multi-facetted approach where diagnostic methods and serological cut-off values may need to be adjusted as further information about the effect of natural

  10. A novel A2 allele found in Leishmania (Leishmania infantum chagasi Novo alelo do gene A2 descrito em Leishmania (Leishmania infantum chagasi

    Directory of Open Access Journals (Sweden)

    Trícia Maria Ferreira de Sousa Oliveira

    2011-03-01

    Full Text Available Visceral leishmaniasis (VL is a widely spread zoonotic disease. In Brazil the disease is caused by Leishmania (Leishmania infantum chagasi. Peridomestic sandflies acquire the etiological agent by feeding on blood of infected reservoir animals, such as dogs or wildlife. The disease is endemic in Brazil and epidemic foci have been reported in densely populated cities all over the country. Many clinical features of Leishmania infection are related to the host-parasite relationship, and many candidate virulence factors in parasites that cause VL have been studied such as A2 genes. The A2 gene was first isolated in 1994 and then in 2005 three new alleles were described in Leishmania (Leishmania infantum. In the present study we amplified by polymerase chain reaction (PCR and sequenced the A2 gene from the genome of a clonal population of L. (L. infantum chagasi VL parasites. The L. (L. infantum chagasi A2 gene was amplified, cloned, and sequenced in. The amplified fragment showed approximately 90% similarity with another A2 allele amplified in Leishmania (Leishmania donovani and in L.(L. infantum described in literature. However, nucleotide translation shows differences in protein amino acid sequence, which may be essential to determine the variability of A2 genes in the species of the L. (L. donovani complex and represents an additional tool to help understanding the role this gene family may have in establishing virulence and immunity in visceral leishmaniasis. This knowledge is important for the development of more accurate diagnostic tests and effective tools for disease control.A leishmaniose visceral (LV é uma zoonose amplamente disseminada, causada no Brasil pela Leishmania (Leishmania infantum chagasi. Flebotomíneos vetores adquirem o agente etiológico, alimentando-se do sangue de animais contaminados, como cachorros ou animais selvagens. A doença é endêmica no Brasil, e focos de epidemia são relatados em cidades densamente povoadas

  11. Leishmania

    Indian Academy of Sciences (India)

    NII

    ... adverse side effect like cardiac failure & acute pancreatitis. Amphotericin B: Costly also very toxic causes cardiotoxicity and nephrotoxicity, require hospitalization. Miltefosine: Originally anticancer drug used in VL, toxic and very costly. No vaccine and appropriate diagnostic procedure are available against leishmaniasis.

  12. Seroprevalence of Neospora caninum in slaughtered native cattle in Kurdistan province, Iran.

    Science.gov (United States)

    Heidari, Heidar; Mohammadzadeh, Abdolmajid; Gharekhani, Jamal

    2014-01-01

    Neospora caninum is a worldwide distributed pathogen which causes abortion in cattle leading to economic loss in the cattle industry. The aim of this study was to determine the seroprevalence of N. caninum antibodies in the native cattle slaughtered in various areas of Kurdistan province (western Iran) from September 2010 to September 2011. Serum samples from 368 cattle slaughtered in seven slaughterhouses in this region were taken for detection of anti-N. caninum antibodies using commercial N. caninum ELISA kit. Antibodies to N. caninum were found in 29 samples (7.80%). The present study was the first report of Neospora infection in this region and indicated that native cattle of Kurdistan province were exposed to this parasite.

  13. Seroprevalence of Neospora caninum in slaughtered native cattle in Kurdistan province, Iran

    Directory of Open Access Journals (Sweden)

    Heidar Heidari

    2014-04-01

    Full Text Available Neospora caninum is a worldwide distributed pathogen which causes abortion in cattle leading to economic loss in the cattle industry. The aim of this study was to determine the seroprevalence of N. caninum antibodies in the native cattle slaughtered in various areas of Kurdistan province (western Iran from September 2010 to September 2011. Serum samples from 368 cattle slaughtered in seven slaughterhouses in this region were taken for detection of anti-N. caninum antibodies using commercial N. caninum ELISA kit. Antibodies to N. caninum were found in 29 samples (7.80%. The present study was the first report of Neospora infection in this region and indicated that native cattle of Kurdistan province were exposed to this parasite.

  14. Seroprevalence of antibodies to Neospora caninum in dogs and raccoon dogs in Korea

    Science.gov (United States)

    Kim, Jae-Hoon; Kang, Min-Soo; Lee, Byung-Chun; Hwang, Woo-Suk; Lee, Chang-Woo; So, Byung-Jae; Dubey, J. P.

    2003-01-01

    Neospora caninum is an important cause of abortion in cattle, and dogs are its only known definitive host. Its seroprevalence among domestic urban and rural dogs and feral raccoon dogs (Nyctereutes procyonoides koreensis) in Korea was studied by indirect fluorescent antibody test (IFAT) and by the neospora agglutination test (NAT), respectively. Antibodies to N. caninum were found in 8.3% of urban dogs and in 21.6% of dogs at dairy farms. Antibody titers ranged from 1:50 to 1:400. Antibodies to N. caninum were found in six (23%) of 26 raccoon dogs. However, the potential role of raccoon dogs as a source of horizontal transmission of bovine neosporosis needs further investigation. The results of this study suggest that there is a close relationship between N. caninum infection among dairy farm dogs and cattle in Korea. This study reports for the first time upon the seroprevalence of N. caninum infection in raccoon dogs in Korea. PMID:14699266

  15. Congenital transmission of Neospora caninum in white-tailed deer (Odocoileus virginianus).

    Science.gov (United States)

    Dubey, J P; Jenkins, M C; Kwok, O C H; Ferreira, L R; Choudhary, S; Verma, S K; Villena, I; Butler, E; Carstensen, M

    2013-09-23

    Neosporosis is an important cause of bovine abortion worldwide. Many aspects of transmission of Neospora caninum in nature are unknown. The white-tailed deer (Odocoileus virginianus) is considered one of the most important wildlife reservoirs of N. caninum in the USA. During the hunting seasons of 2008, 2009, and 2010, brains of 155 white-tailed deer fetuses were bioassayed in mice for protozoal isolation. Viable N. caninum (NcWTDMn1, NcWTDMn2) was isolated from the brains of two fetuses by bioassays in mice, and subsequent propagation in cell culture. Dams of these two infected fetuses had antibodies to N. caninum by Neospora agglutination test at 1:100 serum dilution. DNA obtained from culture-derived N. caninum tachyzoites of the two isolates with Nc5 PCR confirmed diagnosis. Results prove congenital transmission of N. caninum in the white tailed deer for the first time. Published by Elsevier B.V.

  16. Estudo prospectivo de Neospora caninum em cães do sul de Minas Gerais

    OpenAIRE

    Nogueira, Clayton Israel

    2013-01-01

    Neospora caninum é considerado um importante agente causador de abortos em bovinos, porém se desconhece sua frequência e real importância como causador de lesões e doença clínica em cães da região Sul de Minas Gerais. Este estudo foi dividido em duas partes. Na primeira, determinou-se a soroprevalência de anticorpos anti-Neospora caninum e investigou-se os fatores de risco relacionados à sorologia em cães de zonas urbana e rural de propriedades com diferentes atividades econômicas (produção d...

  17. Experimental neosporosis in chickens (Gallus gallus domesticus) with oocysts and tachyzoites of two recent isolates of Neospora caninum reveals resistance to infection

    Science.gov (United States)

    The importance of birds in the biological cycle of Neospora caninum is not clear. Here, we report unsuccessful Neospora infection in Chickens (Gallus gallus domesticus) using two isolates of N. caninum. In experiment #1 conducted in Brazil, 30 White Leghorn chickens were orally inoculated with viabl...

  18. Genetic diversity of Plasmodium vivax and Plasmodium falciparum in Honduras.

    Science.gov (United States)

    Lopez, Ana Cecilia; Ortiz, Andres; Coello, Jorge; Sosa-Ochoa, Wilfredo; Torres, Rosa E Mejia; Banegas, Engels I; Jovel, Irina; Fontecha, Gustavo A

    2012-11-26

    Understanding the population structure of Plasmodium species through genetic diversity studies can assist in the design of more effective malaria control strategies, particularly in vaccine development. Central America is an area where malaria is a public health problem, but little is known about the genetic diversity of the parasite's circulating species. This study aimed to investigate the allelic frequency and molecular diversity of five surface antigens in field isolates from Honduras. Five molecular markers were analysed to determine the genotypes of Plasmodium vivax and Plasmodium falciparum from endemic areas in Honduras. Genetic diversity of ama-1, msp-1 and csp was investigated for P. vivax, and msp-1 and msp-2 for P. falciparum. Allelic frequencies were calculated and sequence analysis performed. A high genetic diversity was observed within Plasmodium isolates from Honduras. A different number of genotypes were elucidated: 41 (n = 77) for pvama-1; 23 (n = 84) for pvcsp; and 23 (n = 35) for pfmsp-1. Pvcsp sequences showed VK210 as the only subtype present in Honduran isolates. Pvmsp-1 (F2) was the most polymorphic marker for P. vivax isolates while pvama-1 was least variable. All three allelic families described for pfmsp-1 (n = 30) block 2 (K1, MAD20, and RO33), and both allelic families described for the central domain of pfmsp-2 (n = 11) (3D7 and FC27) were detected. However, K1 and 3D7 allelic families were predominant. All markers were randomly distributed across the country and no geographic correlation was found. To date, this is the most complete report on molecular characterization of P. vivax and P. falciparum field isolates in Honduras with regards to genetic diversity. These results indicate that P. vivax and P. falciparum parasite populations are highly diverse in Honduras despite the low level of transmission.

  19. PCR detection of Neospora caninum, Toxoplasma gondii and Encephalitozoon cuniculi in brains of wild carnivores

    Czech Academy of Sciences Publication Activity Database

    Hůrková, L.; Modrý, David

    2006-01-01

    Roč. 137, 1/2 (2006), s. 150-154 ISSN 0304-4017 R&D Projects: GA ČR GD524/03/H133 Grant - others:MŠk(CZ) FRVŠ 1494/2004 Institutional research plan: CEZ:AV0Z60220518 Keywords : Neospora * Encephalitozoon * carnivores Subject RIV: EB - Genetics ; Molecular Biology Impact factor: 1.900, year: 2006

  20. NLRP3 inflammasome activation in murine macrophages caused by Neospora caninum infection.

    Science.gov (United States)

    Wang, Xiaocen; Gong, Pengtao; Zhang, Xu; Wang, Jielin; Tai, Lixin; Wang, Xu; Wei, Zhengkai; Yang, Yongjun; Yang, Zhengtao; Li, Jianhua; Zhang, Xichen

    2017-05-30

    Neospora caninum is an intracellular parasite that causes significant economic losses in cattle industry. Understanding the host resistance mechanisms in the innate immune response to neosporosis could facilitate the exploration of approaches for controlling N. caninum infection. The NLR inflammasome is a multiprotein platform in the cell cytoplasm and plays critical roles in the host response against microbes. Neospora caninum-infected wild-type (WT) macrophages and Nlrp3 -/- macrophages, and inhibitory approaches were used to investigate inflammasome activation and its role in N. caninum infection. Inflammasome RT Profiler PCR Arrays were used to identify the primary genes involved in N. caninum infection. The expression of the sensor protein NLRP3, processing of caspase-1, secretion of IL-1β and cell death were detected. Neospora caninum replication in macrophages was also assessed. Many NLR molecules participated in the recognition of N. caninum, especially the sensor protein NLRP3, and further study revealed that the NLRP3 distribution became punctate in the cell cytoplasm, which facilitated inflammasome activation. Inflammasome activation-mediated caspase-1 processing and IL-1β cleavage in response to N. caninum infection were observed and were correlated with the time of infection and number of infecting parasites. LDH-related cell death was also observed, and this death was regarded as beneficial for the clearance of N. caninum. Treatment of N. caninum-infected macrophages with caspase-1, pan-caspase and NLRP3 inhibitors led to the impaired release of active IL-1β and a failure to restrict parasite replication. And Neospora caninum infected peritoneal macrophages from Nlrp3-deficient mice displayed greatly decreased release of active IL-1β and the failure of caspase-1 cleavage. The NLRP3 inflammasome can be activated in N. caninum-infected macrophages, and plays a protective role in the host response to control N. caninum.

  1. Macrophage depletion prior to Neospora caninum infection results in severe neosporosis in mice.

    Science.gov (United States)

    Abe, Chisa; Tanaka, Sachi; Ihara, Fumiaki; Nishikawa, Yoshifumi

    2014-08-01

    We observed that murine macrophages showed greater activation and increased interleukin 6 (IL-6), IL-12p40, and interferon gamma (IFN-γ) production during Neospora caninum infection. Many macrophages migrated to the site of infection. Furthermore, macrophage-depleted mice exhibited increased sensitivity to N. caninum infection. This study indicates that macrophages are required for achieving protective immunity against N. caninum. Copyright © 2014, American Society for Microbiology. All Rights Reserved.

  2. Plasmodium vivax Malaria in Cambodia.

    Science.gov (United States)

    Siv, Sovannaroth; Roca-Feltrer, Arantxa; Vinjamuri, Seshu Babu; Bouth, Denis Mey; Lek, Dysoley; Rashid, Mohammad Abdur; By, Ngau Peng; Popovici, Jean; Huy, Rekol; Menard, Didier

    2016-12-28

    The Cambodian National Strategic Plan for Elimination of Malaria aims to move step by step toward elimination of malaria across Cambodia with an initial focus on Plasmodium falciparum malaria before achieving elimination of all forms of malaria, including Plasmodium vivax in 2025. The emergence of artemisinin-resistant P. falciparum in western Cambodia over the last decade has drawn global attention to support the ultimate goal of P. falciparum elimination, whereas the control of P. vivax lags much behind, making the 2025 target gradually less achievable unless greater attention is given to P. vivax elimination in the country. The following review presents in detail the past and current situation regarding P. vivax malaria, activities of the National Malaria Control Program, and interventional measures applied. Constraints and obstacles that can jeopardize our efforts to eliminate this parasite species are discussed. © The American Society of Tropical Medicine and Hygiene.

  3. Plasmodium vivax Malaria in Cambodia

    Science.gov (United States)

    Siv, Sovannaroth; Roca-Feltrer, Arantxa; Vinjamuri, Seshu Babu; Bouth, Denis Mey; Lek, Dysoley; Rashid, Mohammad Abdur; By, Ngau Peng; Popovici, Jean; Huy, Rekol; Menard, Didier

    2016-01-01

    The Cambodian National Strategic Plan for Elimination of Malaria aims to move step by step toward elimination of malaria across Cambodia with an initial focus on Plasmodium falciparum malaria before achieving elimination of all forms of malaria, including Plasmodium vivax in 2025. The emergence of artemisinin-resistant P. falciparum in western Cambodia over the last decade has drawn global attention to support the ultimate goal of P. falciparum elimination, whereas the control of P. vivax lags much behind, making the 2025 target gradually less achievable unless greater attention is given to P. vivax elimination in the country. The following review presents in detail the past and current situation regarding P. vivax malaria, activities of the National Malaria Control Program, and interventional measures applied. Constraints and obstacles that can jeopardize our efforts to eliminate this parasite species are discussed. PMID:27708187

  4. Development of maternal and foetal immune responses in cattle following experimental challenge with Neospora caninum at day 210 of gestation.

    Science.gov (United States)

    Bartley, Paul M; Katzer, Frank; Rocchi, Mara S; Maley, Stephen W; Benavides, Julio; Nath, Mintu; Pang, Yvonne; Cantón, Germán; Thomson, Jackie; Chianini, Francesca; Innes, Elisabeth A

    2013-10-03

    This study examined the immunological responses of pregnant cattle and their foetuses following an experimental challenge with live Neospora caninum tachyzoites at day 210 of gestation. Animals were bled prior to and weekly throughout the experiment and sacrificed at 14, 28, 42 and 56 days post inoculation (dpi). At post mortem examination, samples of lymph nodes and spleen were collected from both dam and foetus for immunological analysis. Subcutaneous (sc) inoculation over the left prefemoral (LPF) lymph node of pregnant cattle at day 210 of gestation, led to the vertical transmission of parasites by 14 dpi, however no foetal deaths were observed in the infected animals. Foetuses from infected dams mounted Neospora-specific humoral and cell-mediated immune (CMI) responses by 14 dpi. These responses involved anti-Neospora IgG, antigen-specific lymphocyte proliferation, and the production of the cytokines IFN-γ, interleukin (IL)-4 and IL-10. There was also evidence of innate immunity during the response against Neospora from infected dams, with statistically significant (p Neospora-specific cell mediated, humoral and innate immune responses.

  5. Gamma interferon production and plasma concentrations of pregnancy-associated glycoproteins 1 and 2 in gestating dairy cows naturally infected with Neospora caninum.

    Science.gov (United States)

    Serrano-Pérez, B; Garcia-Ispierto, I; de Sousa, N M; Beckers, J F; Almería, S; López-Gatius, F

    2014-04-01

    Gamma interferon (IFN-γ) production and cross-breed pregnancy have been attributed a role in protecting dairy cows infected with Neospora caninum against abortion. Plasma levels of pregnancy-associated glycoproteins-1 (PAG-1) are a marker of placental/foetal well-being and of PAG-2 is an abortion risk indicator in chronically N. caninum-infected animals. The present study examines, in cross-breed pregnancies, interactions between IFN-γ production and levels of PAG-1 and PAG-2 in non-aborting naturally Neospora-infected dairy cows. Data were obtained from 60 pregnant Holstein-Friesian cows: 44 Neospora-seropositive and 16 Neospora-seronegative; 12 became pregnant using Holstein-Friesian semen and 48 using Limousin semen. Blood samples were collected on Days 40, 90, 120, 150, 180 and 210 of gestation. Gamma interferon was only detected in the plasma of nine of the 44 Neospora-seropositive cows, all of them became pregnant using Limousin semen. Through GLM procedures, in cows inseminated with Limousin semen and Neospora-seropositive cows showing no IFN-γ production, PAG-1 concentrations were high and increased throughout gestation compared to the levels detected in cows inseminated with Holstein-Friesian semen and Neospora-seropositive cows producing IFN-γ, respectively. In Neospora-seronegative cows and in Neospora-seropositive cows showing no IFN-γ production, significantly increased PAG-2 concentrations were observed on gestation Day 120. Our findings indicate that IFN-γ production correlates negatively and the production of antibodies against N. caninum is uncorrelated with plasma PAG concentrations during gestation in Neospora-infected dairy cows. Accordingly, IFN-γ production could be linked to the transplacental migration of tachyzoites, which may cause a reduction in PAG levels. © 2014 Blackwell Verlag GmbH.

  6. Innate Immunity to Leishmania Infection: Within Phagocytes

    Directory of Open Access Journals (Sweden)

    Marcela Freitas Lopes

    2014-01-01

    Full Text Available Infection by Leishmania takes place in the context of inflammation and tissue repair. Besides tissue resident macrophages, inflammatory macrophages and neutrophils are recruited to the infection site and serve both as host cells and as effectors against infection. Recent studies suggest additional important roles for monocytes and dendritic cells. This paper addresses recent experimental findings regarding the regulation of Leishmania major infection by these major phagocyte populations. In addition, the role of IL-4 on dendritic cells and monocytes is discussed.

  7. In-Silico detection of chokepoints enzymes in four plasmodium species

    African Journals Online (AJOL)

    Of the over 156 species of Plasmodium that infect vertebrates, only four infect man: Plasmodium falciparum, Plasmodium vivax, Plasmodium ovale and Plasmodium malariae. Other species infect other animals including birds, reptiles and rodents. The rodent malaria parasites are Plasmodium berghei, Plasmodium yoelii, ...

  8. Susceptibility of spiny rats (Proechimys semispinosus to Leishmania (Viannia panamensis and Leishmania (Leishmania chagasi

    Directory of Open Access Journals (Sweden)

    BL Travi

    2002-09-01

    Full Text Available The role of Proechimys semispinosus as reservoir of Leishmania (Viannia panamensis on the Colombian Pacific coast was experimentally evaluated. The susceptibility to L. chagasi also was assessed to determine the utility of this rodent as a model for studying reservoir characteristics in the laboratory. Wild-caught animals were screened for natural trypanosomatid infections, and negative individuals were inoculated intradermally (ID in the snout or feet with 10(7 promastigotes of L. panamensis. L. chagasi was inoculated intracardially (10(7 promastigotes or ID in the ear (10(8 promastigotes. PCR-hybridization showed that 15% of 33 spiny rats were naturally infected with L. Viannia sp. Animals experimentally infected with L. panamensis developed non-ulcerated lesions that disappeared by the 7th week post-infection (p.i. and became more resistant upon reinfection. Infectivity to sand flies was low (1/20-1/48 infected/fed flies and transient, and both culture and PCR-hybridization showed that L. panamensis was cleared by the 13th week p.i. Animals inoculated with L. chagasi became subclinically infected and were non-infective to sand flies. Transient infectivity to vectors of spiny rats infected with L. panamensis, combined with population characteristics, e.g., abundance, exploitation of degraded habitats and high reproductive rates, could make them epidemiologically suitable reservoirs.

  9. First Cases of Cutaneous Leishmaniasis Caused by Leishmania (Viannia) naiffi Infection in Surinam

    NARCIS (Netherlands)

    van Thiel, Pieter-Paul A. M.; van Gool, Tom; Kager, Piet A.; Bart, Aldert

    2010-01-01

    Cutaneous leishmaniasis in Surinam is generally caused by infection by Leishmania guyanensis. We report three cases of infection with Leishmania (Viannia) naiffi, a Leishmania species not described from Surinam before. Treatment with pentamidine proved to be effective

  10. Developmentally regulated sphingolipid degradation in Leishmania major.

    Directory of Open Access Journals (Sweden)

    Ou Zhang

    Full Text Available Leishmania parasites alternate between extracellular promastigotes in sandflies and intracellular amastigotes in mammals. These protozoans acquire sphingolipids (SLs through de novo synthesis (to produce inositol phosphorylceramide and salvage (to obtain sphingomyelin from the host. A single ISCL (Inositol phosphoSphingolipid phospholipase C-Like enzyme is responsible for the degradation of both inositol phosphorylceramide (the IPC hydrolase or IPCase activity and sphingomyelin (the SMase activity. Recent studies of a L. major ISCL-null mutant (iscl(- indicate that SL degradation is required for promastigote survival in stationary phase, especially under acidic pH. ISCL is also essential for L. major proliferation in mammals. To further understand the role of ISCL in Leishmania growth and virulence, we introduced a sole IPCase or a sole SMase into the iscl(- mutant. Results showed that restoration of IPCase only complemented the acid resistance defect in iscl(- promastigotes and improved their survival in macrophages, but failed to recover virulence in mice. In contrast, a sole SMase fully restored parasite infectivity in mice but was unable to reverse the promastigote defects in iscl(-. These findings suggest that SL degradation in Leishmania possesses separate roles in different stages: while the IPCase activity is important for promastigote survival and acid tolerance, the SMase activity is required for amastigote proliferation in mammals. Consistent with these findings, ISCL was preferentially expressed in stationary phase promastigotes and amastigotes. Together, our results indicate that SL degradation by Leishmania is critical for parasites to establish and sustain infection in the mammalian host.

  11. Involvement of Leishmania donovani major surface glycoprotein ...

    Indian Academy of Sciences (India)

    The major surface glycoprotein gp63 of the kinetoplastid protozoal parasite Leishmania is implicated as a ligand mediating uptake of the parasite into, and survival within, the host macrophage. By expressing gp63 antisense RNA from an episomal vector in L. donovani promastigotes, gp63-deficient transfectants were ...

  12. Asociación entre variables reproductivas y anticuerpos anti Neospora caninum en bovinos lecheros de un municipio de Colombia

    OpenAIRE

    Martín Orlando Pulido Medellín; Adriana María Díaz Anaya; Roy José Andrade Becerra

    2017-01-01

    El objetivo fue determinar el porcentaje de vacas seropositivas a Neospora caninum y la identificación de las variables reproductivas que se encuentran relacionadas con la presencia de anticuerpos contra este protozoo. Se tomaron 1,000 muestras de sangre a hembras bovinas del municipio de Sotaquirá, Boyacá, las cuales fueron evaluadas por medio de ELISA indirecta. Se determinó una seroprevalencia de Neospora caninum del 45 %; las variables reproductivas asociadas con la positividad de N. cani...

  13. Control of Plasmodium knowlesi malaria

    Science.gov (United States)

    Abdullahi, Mohammed Baba; Hasan, Yahya Abu; Abdullah, Farah Aini

    2015-10-01

    The most significant and efficient measures against Plasmodium knowlesi outbreaks are efficient anti malaria drug, biological control in form of predatory mosquitoes and culling control strategies. In this paper optimal control theory is applied to a system of ordinary differential equation. It describes the disease transmission and Pontryagin's Maximum Principle is applied for analysis of the control. To this end, three control strategies representing biological control, culling and treatment were incorporated into the disease transmission model. The simulation results show that the implementation of the combination strategy during the epidemic is the most cost-effective strategy for disease transmission.

  14. The Plasmodium export element revisited.

    Directory of Open Access Journals (Sweden)

    Jan Alexander Hiss

    Full Text Available We performed a bioinformatical analysis of protein export elements (PEXEL in the putative proteome of the malaria parasite Plasmodium falciparum. A protein family-specific conservation of physicochemical residue profiles was found for PEXEL-flanking sequence regions. We demonstrate that the family members can be clustered based on the flanking regions only and display characteristic hydrophobicity patterns. This raises the possibility that the flanking regions may contain additional information for a family-specific role of PEXEL. We further show that signal peptide cleavage results in a positional alignment of PEXEL from both proteins with, and without, a signal peptide.

  15. The periodicity of Plasmodium vivax and Plasmodium falciparum in Venezuela.

    Science.gov (United States)

    Grillet, María-Eugenia; El Souki, Mayida; Laguna, Francisco; León, José Rafael

    2014-01-01

    We investigated the periodicity of Plasmodium vivax and P. falciparum incidence in time-series of malaria data (1990-2010) from three endemic regions in Venezuela. In particular, we determined whether disease epidemics were related to local climate variability and regional climate anomalies such as the El Niño Southern Oscillation (ENSO). Malaria periodicity was found to exhibit unique features in each studied region. Significant multi-annual cycles of 2- to about 6-year periods were identified. The inter-annual variability of malaria cases was coherent with that of SSTs (ENSO), mainly at temporal scales within the 3-6 year periods. Additionally, malaria cases were intensified approximately 1 year after an El Niño event, a pattern that highlights the role of climate inter-annual variability in the epidemic patterns. Rainfall mediated the effect of ENSO on malaria locally. Particularly, rains from the last phase of the season had a critical role in the temporal dynamics of Plasmodium. The malaria-climate relationship was complex and transient, varying in strength with the region and species. By identifying temporal cycles of malaria we have made a first step in predicting high-risk years in Venezuela. Our findings emphasize the importance of analyzing high-resolution spatial-temporal data to better understand malaria transmission dynamics. Copyright © 2013 Elsevier B.V. All rights reserved.

  16. [Congenital malaria due to Plasmodium falciparum and Plasmodium malariae].

    Science.gov (United States)

    Zenz, W; Trop, M; Kollaritsch, H; Reinthaler, F

    2000-05-19

    Increasing tourism and growing numbers of immigrants from malaria-endemic countries are leading to a higher importation rate of rare tropical disorders in European countries. We describe, to the best of our knowledge, the first case of connatal malaria in Austria. The patient is the first child of a 24 year old mother who was born in Ghana and immigrated to Austria one and a half years before delivery. She did not stay in an endemic region during this period and did not show fever or any other signs of malaria. The boy was healthy for the first six weeks of his life. In the 8th week of life he was admitted to our hospital due to persistent fever of unknown origin. On physical examination he showed only mild splenomegaly. Routine laboratory testing revealed mild hemolytic anemia with a hemoglobin value of 8.3 g/l. In the blood smear Plasmodium falciparum and Plasmodium malariae were detected. Oral therapy with quinine hydrochloride was successful and blood smears became negative for Plasmodia within 6 days. This case shows that congenital malaria can occur in children of clinically healthy women who were born in malaria-endemic areas even one and a half year after they have immigrated to non-endemic regions.

  17. Humoral immune reaction of newborn calves congenitally infected with Neospora caninum and experimentally treated with toltrazuril.

    Science.gov (United States)

    Haerdi, Corinne; Haessig, Michael; Sager, Heinz; Greif, Gisela; Staubli, Daniela; Gottstein, Bruno

    2006-10-01

    Neospora caninum is widely recognized as one of the most important infectious organisms causing abortion and stillbirth in cattle. This parasite causes severe economical losses worldwide. Infection is mostly passed vertically from mother to calf during pregnancy. Under certain circumstances, an infection can lead to abortion, but in most cases it results in a chronically infected calf, which itself will represent the next endogenously infectious generation. So far, no reliable therapeutic or metaphylactic tool has been developed. One possibility to control the problem may consist of treating newborn calves that became vertically infected by a persistently infected mother. This may allow parasite-free offspring. The aim of the present study was to address the questions: (1) can serology be used to assess efficiency of treatment in toltrazuril-medicated animals? and (2) is a strategic prevention measure possible by means of producing N. caninum-free calves from positive cows? Calves from Neospora-seropositive cows and heifers were randomly split into two different medication groups: 36 calves were medicated with toltrazuril and 36 calves obtained a placebo. Medication (20 mg toltrazuril per kg bw) was administered three times, every second day, within the 7 days post natum. Three months after medication, there was no difference in antibody reactivity between the two groups. At later time points (4-6 months), however, significant differences were found, as explained by a strong humoral immunity after chemotherapeutical affection of parasites, while the placebo-treated animals only responded weakly to the persistent infection. In summary, we concluded that (1) serology was not an entirely appropriate tool to answer our initial question and (2) toltrazuril has the potential to eliminate N. caninum in newborn calves. As a consequence, we plan to follow up toltrazuril-medicated calves clinically and serologically over a longer period and investigate if they give birth to

  18. Identification and characterization of GRA6/GRA7 of Neospora caninum in MDBK cells.

    Science.gov (United States)

    Dong, Jingquan; Li, Jianhua; Wang, Jinpeng; Li, Fei; Yang, Ju; Gong, Pengtao; Li, He; Zhang, Xichen

    2017-04-01

    Neospora caninum, an apicomplexan parasite, is recognized as a major bovine abortifacient. Dense granule antigens (GRAs) play important roles in the formation and modification of parasitophorous vacuoles (PVs) in Toxoplasma gondii. However, a few studies investigating GRAs have been reported in N. caninum. The aim of the present study was to characterize the dense GRA6/GRA7 of N. caninum in PVs using MDBK cells as a host cell model. Neospora caninum was inoculated into MDBK cells, and changes were observed using a transmission electron microscope (TEM). Neospora caninum GRA6/GRA7 were identified and characterized using bioinformatics, cell fractionation, and immunofluorescence. The TEM results revealed that integrated PVs were present in MDBK cells after N. caninum infection. Bioinformatics analysis showed that NcGRA6/NcGRA7 shared 28.76% and 29.66% homology with T. gondii GRA6/GRA7 (TgGRA6/TgGRA7) but had similar signal peptides, transmembrane domains, and motifs. Cell fractionation and subcellular localization analyses both showed that NcGRA6 was distributed in the lumen and intravacuolar network in soluble and transmembrane forms. The transmembrane form of NcGRA7 was observed in the PV membrane. These data lay a foundation for further study on bovine neosporosis and NcGRA6/NcGRA7 function during PV formation. © The Author 2017. Published by Oxford University Press on behalf of the Institute of Biochemistry and Cell Biology, Shanghai Institutes for Biological Sciences, Chinese Academy of Sciences. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

  19. Identification and characterization of Neospora caninum tachyzoite antigens useful for diagnosis of neosporosis.

    Science.gov (United States)

    Bjerkas, I; Jenkins, M C; Dubey, J P

    1994-01-01

    The purpose of the present study was to identify antigens of the protozoan Neospora caninum that could be useful for the diagnosis of neosporosis in domestic animals. As revealed by immunoblotting, immune sera from a wide range of animal species exhibited a similar recognition pattern of four major and several minor N. caninum antigens. In contrast to preinoculation sera, all tested immune sera recognized nonreduced immunodominant 17-, 29-, 30-, and 27-kDa antigens. A 46-kDa protein which showed faint recognition by preimmune sera also exhibited a strong response by immune sera. Immunolocalization of the four immunodominant N. caninum antigens was investigated by immunogold electron microscopy using monospecific polyclonal antisera. The 17-kDa antigen appears to be associated with the body part of the rhoptries, while the 29- and 30-kDa antigens were associated with the dense granules, network, and limiting membrane of the parasitophorous vacuole. Studies were also conducted to compare antibody responses to N. caninum and the related protozoan Toxoplasma gondii. Although N. caninum and T. gondii (RH strain) tachyzoites shared a few cross-reacting antigens, the immunodominant antigens of both parasites were not recognized by heterologous sera. Also, immunogold staining with rabbit anti-Neospora hyperimmune serum exhibited almost no labeling of external membranes of Neospora tachyzoites compared with the very marked labeling seen when Toxoplasma tachyzoites (RH strain) were incubated with rabbit anti-Toxoplasma hyperimmune serum. These unique antigenic differences should be useful in developing a diagnostic assay for N. caninum. Images PMID:7496948

  20. Dairy cow abortion associated with Neospora caninum and other infectious agents Aborto em vacas leiteiras associado a Neospora caninum e a outros agentes infecciosos

    Directory of Open Access Journals (Sweden)

    A.P.M.E. Santos

    2005-08-01

    Full Text Available Trinta e cinco vacas de rebanhos leiteiros da região Norte do estado do Paraná, com histórico de abortamento, foram pesquisadas sorologicamente para verificar a presença de anticorpos contra Neospora caninum, Toxoplasma gondii, Leptospira spp., Brucella abortus, BHV-1 e BVDV. Vinte e uma vacas apresentaram títulos sorológicos compatíveis com infecção. Todas elas, soropositivas para N. caninum, foram também soropositivas para outros agentes infecciosos, sugerindo a possibilidade de associação desses agentes nos problemas reprodutivos de bovinos, no estado do Paraná.

  1. Extensive production of Neospora caninum tissue cysts in a carnivorous marsupial succumbing to experimental neosporosis

    Directory of Open Access Journals (Sweden)

    King Jessica S

    2011-06-01

    Full Text Available Abstract Experimental infections of Sminthopsis crassicaudata, the fat-tailed dunnart, a carnivorous marsupial widely distributed throughout the arid and semi-arid zones of Australia, show that this species can act as an intermediate host for Neospora caninum. In contrast to existing models that develop relatively few N. caninum tissue cysts, dunnarts offer a new animal model in which active neosporosis is dominated by tissue cyst production. The results provide evidence for a sylvatic life cycle of N. caninum in Australia between marsupials and wild dogs. It establishes the foundation for an investigation of the impact and costs of neosporosis to wildlife.

  2. Seroprevalence and risk factors for Neospora caninum in small dairy farms in central Chile

    OpenAIRE

    Luis Hervé-Claude1; Alan Lavado A; Dacil Rivera O; María Navarrete-Talloni; Christopher Hamilton-West M

    2017-01-01

    Objetivos. Proveer información sobre la seroprevalencia y factores de riesgo asociados a la infección por Neospora caninum en bovinos en Chile central. Materiales y métodos. La población estudiada corresponde a pequeñas lecherías que son parte de un programa gubernamental de Asistencia Técnica (SAT), en la región de O´Higgins en Chile central. Muestras de suero fueron recolectadas desde vacas en lactancia y analizadas mediante un kit comercial ELISA. Además, se aplicó un cuestionario a los du...

  3. Extensive production of Neospora caninum tissue cysts in a carnivorous marsupial succumbing to experimental neosporosis

    Science.gov (United States)

    2011-01-01

    Experimental infections of Sminthopsis crassicaudata, the fat-tailed dunnart, a carnivorous marsupial widely distributed throughout the arid and semi-arid zones of Australia, show that this species can act as an intermediate host for Neospora caninum. In contrast to existing models that develop relatively few N. caninum tissue cysts, dunnarts offer a new animal model in which active neosporosis is dominated by tissue cyst production. The results provide evidence for a sylvatic life cycle of N. caninum in Australia between marsupials and wild dogs. It establishes the foundation for an investigation of the impact and costs of neosporosis to wildlife. PMID:21635733

  4. Loss of infectivity of Neospora caninum oocysts maintained for a prolonged time

    Science.gov (United States)

    Uzeda, Rosangela Soares; Costa, Kattyanne De Souza; Santos, Sara Lima; Pinheiro, Alexandre Moraes; De Almeida, Maria Angela Ornelas; McAllister, Milton M.

    2007-01-01

    The purpose of this study was to investigate whether sporulated Neospora caninum oocysts, which had been stored for 46 mo in a 2% sulfuric acid solution at 4℃, remain morphologically viable and infective to gerbils (Meriones unguiculatus). Six gerbils were orally inoculated with doses of 400 or 1,200 oocysts. Two mo after inoculation, the animals did not show any clinical signs, had no histological lesions, and were seronegative for N. caninum at 1: 50 in an immunofluorescent antibody test. PCR using the brain from each gerbil did not reveal N. caninum specific DNA. We conclude that oocysts preserved for 46 mo are not infective, despite being morphologically intact. PMID:18165712

  5. Desarrollo de vacunas frente a la neosporosis bovina utilizando aislados de "Neospora caninum" inactivados y atenuados

    OpenAIRE

    Rojo Montejo, Silvia

    2012-01-01

    Neospora caninum es un parásito intracelular formador de quistes considerado mundialmente como una de las principales causas de aborto en el ganado bovino.La magnitud de las pérdidas económicas asociadas a la neosporosis bovina, junto con la ausencia de medidas económicamente viables para su control, han conducido a que uno de los principales retos en la investigación sobre esta enfermedad sea el desarrollo de una vacuna eficaz, segura y rentable frente al aborto y la transmisión del parás...

  6. FRECUENCIA DE Neospora caninum EN PERROS DE ESTABLOS LECHEROS DEL VALLE DE LIMA

    OpenAIRE

    del Campo S., Jorge; Practica privada; Chávez V., Amanda; Laboratorio de Microbiología y Parasitología Veterinaria, Facultad de Medicina Veterinaria, Universidad Nacional Mayor de San Marcos, Lima Perú.; Delgado C., Alfredo; Clínica de Animales Mayores, Facultad de Medicina Veterinaria, Universidad Nacional Mayor de San Marcos, Lima Perú.; Falcón P., Néstor; Laboratorio de Medicina Veterinaria Preventiva, Facultad de Medicina Veterinaria, Universidad Nacional Mayor de San Marcos, Lima Perú.; Ornelas A., Ângela; Laboratório Parasitoses, Escola de Medicina Veterinária, Universidade Federal da Bahía, Brasil; Casas A., Eva; Laboratorio de Microbiología y Parasitología Veterinaria, Facultad de Medicina Veterinaria, Universidad Nacional Mayor de San Marcos, Lima Perú.; Serrano M., Enrique; Laboratorio de Microbiología y Parasitología Veterinaria, Facultad de Medicina Veterinaria, Universidad Nacional Mayor de San Marcos, Lima Perú.

    2013-01-01

    La neosporosis es una enfermedad parasitaria ocasionada por el Neospora caninum, que cursa con problemas reproductivos en el ganado lechero y signos nerviosos en el perro, el cual es el hospedero definitivo. El objetivo del estudio fue determinar la frecuencia de N. caninum en perros de establos lecheros del valle de Lima. Se evaluaron 104 muestras de suero de caninos mayores a 3 meses de edad, provenientes de 23 establos lecheros, mediante la detección de anticuerpos contra N. caninum a trav...

  7. Extensive production of Neospora caninum tissue cysts in a carnivorous marsupial succumbing to experimental neosporosis.

    Science.gov (United States)

    King, Jessica S; McAllan, Bronwyn; Spielman, Derek S; Lindsay, Scott A; Hůrková-Hofmannová, Lada; Hartigan, Ashlie; Al-Qassab, Sarwat E; Ellis, John T; Slapeta, Jan

    2011-06-02

    Experimental infections of Sminthopsis crassicaudata, the fat-tailed dunnart, a carnivorous marsupial widely distributed throughout the arid and semi-arid zones of Australia, show that this species can act as an intermediate host for Neospora caninum. In contrast to existing models that develop relatively few N. caninum tissue cysts, dunnarts offer a new animal model in which active neosporosis is dominated by tissue cyst production. The results provide evidence for a sylvatic life cycle of N. caninum in Australia between marsupials and wild dogs. It establishes the foundation for an investigation of the impact and costs of neosporosis to wildlife.

  8. Neospora caninum and Toxoplasma gondii in brain tissue of feral rodents and insectivores caught on farms in the Netherlands

    NARCIS (Netherlands)

    Meerburg, B.G.; Craeye, de S.; Dierick, K.; Kijlstra, A.

    2012-01-01

    We investigated the presence of both Neospora caninum and Toxoplasma gondii in 250 brain tissue samples from 9 species of feral rodents and insectivores caught on 10 organic farms in the Netherlands in 2004. Collected samples were conserved in 4% paraformaldehyde solution and analysed by real-time

  9. Tunicamycins, a class of nucleoside antibiotics similar to corynetoxins of the Rathayibactor toxicus, increase susceptibility of mice to Neospora caninum

    Science.gov (United States)

    Neosporosis is the leading cause of abortion in cattle. Neospora caninum-associated abortion may exhibit both endemic and epidemic patterns. It was reported that the epidemic outbreaks took place in the form of “abortion storms” and were not significantly correlated with seasonal changes or consumpt...

  10. Antigen-Specific CD8+ T Cells Protect against Lethal Toxoplasmosis in Mice Infected with Neospora caninum

    Science.gov (United States)

    Kasper, Lloyd H.; Khan, Imtiaz A.

    1998-01-01

    Neospora caninum is a coccidial protozoan parasite that appears morphologically indistinguishable from Toxoplasma gondii and that infects a large range of mammals. Both inbred and outbred strains of mice exhibit a high degree of resistance to infection with N. caninum. Three inbred strains of mice (A/J, BALB/c, and C57BL/6) that were infected intraperitoneally with N. caninum were protected against a lethal challenge from T. gondii. Vaccine-induced protection was Neospora dose dependent. A rise in the CD8+ T-cell population in mice that had been vaccinated with N. caninum and challenged with T. gondii was observed. Adoptive transfer of CD8+ T-cell splenocytes from N. caninum-infected mice was protective against challenge with Toxoplasma. The CD8+ T cells from Neospora-infected mice proliferate to both Neospora and Toxoplasma antigens in vitro and secrete substantial quantities of gamma interferon when pulsed with the parasite antigen. These observations demonstrate that N. caninum protects against lethal T. gondii infection by the induction of CD8+ T cells that are immunoreactive to both parasites. PMID:9529081

  11. The effect of the dam-calf relationship on serostatus to Neospora caninum on 20 Costa Rican dairy farms

    NARCIS (Netherlands)

    Romero Zúñiga, J.J.; Frankena, K.

    2003-01-01

    An epidemiological study was conduced on 20 dairy herds previously diagnosed as seropositive for Neospora caninum. The number of females per farm varies from 41 to 296. All females present on the farms were bled once in the period of July and August 2000. A total of 3002 females were bled. An

  12. Seroprevalence of Toxoplasma gondii and Neospora caninum in feral cats (Felis silvestris catus) in Majorca, Balearic Islands, Spain

    Science.gov (United States)

    Felids are important in the epidemiology of Toxoplasma gondii infection because they are the only hosts that can excrete environmentally-resistant oocysts. Antibodies to T. gondii and Neospora caninum were determined in serum samples from 59 feral cats (Felis silvestris catus) captured in baited tra...

  13. High seroprevalence of Toxoplasma gondii and Neospora caninum in the Common raven (Corvus corax) in the Northeast of Spain

    Science.gov (United States)

    In recent years, multiple cases of aggressive behaviour of Common ravens (Corvus corax) have been reported by farmers in Catalonia (NE Spain), including attacking of newborn animals and consumption of dead foetuses. In the present study, seroprevalence of Toxoplasma gondii and Neospora caninum was d...

  14. Foetal death in naive heifers inoculated with Neospora caninum isolate Nc-Spain7 at 110 days of pregnancy

    Science.gov (United States)

    Neospora caninum infection is a leading cause of abortion in cattle worldwide. The pathogenesis of bovine neosporosis, particularly during the second term of gestation, when most abortions occur in naturally infected dams, is poorly understood. In the present study foetal death was observed in 3 of ...

  15. Identification of Protein Markers in Patients Infected with Plasmodium knowlesi, Plasmodium falciparum and Plasmodium vivax

    Directory of Open Access Journals (Sweden)

    Alan Kang-Wai Mu

    2014-11-01

    Full Text Available Malaria is caused by parasitic protozoans of the genus Plasmodium and is one of the most prevalent infectious diseases in tropical and subtropical regions. For this reason, effective and practical diagnostic methods are urgently needed to control the spread of malaria. The aim of the current study was to identify a panel of new malarial markers, which could be used to diagnose patients infected with various Plasmodium species, including P. knowlesi, P. vivax and P. falciparum. Sera from malaria-infected patients were pooled and compared to control sera obtained from healthy individuals using the isobaric tags for relative and absolute quantitation (iTRAQ technique. Mass spectrometry was used to identify serum proteins and quantify their relative abundance. We found that the levels of several proteins were increased in pooled serum from infected patients, including cell adhesion molecule-4 and C-reactive protein. In contrast, the serum concentration of haptoglobin was reduced in malaria-infected individuals, which we verified by western blot assay. Therefore, these proteins might represent infectious markers of malaria, which could be used to develop novel diagnostic tools for detecting P. knowlesi, P. vivax and P. falciparum. However, these potential malarial markers will need to be validated in a larger population of infected individuals.

  16. Adenine phosphoribosyltransferase-deficient Leishmania donovani

    International Nuclear Information System (INIS)

    Kaur, K.; Iovannisci, D.M.; Ullman, B.

    1986-01-01

    To elucidate the relative roles of two routes for adenine salvage, the authors use biochemical genetic approaches to isolate clonal strains of Leishmania donovani promasatigotes genetically deficient in APRTase activity. The studies suggest that the metabolic rate of adenine in these organisms is initiated by deamination. The radiolabel incorporation experiments and biochemical experiments are described in which the rate of uptake of radiolabelled purine nucleobases (C 14) was determined. Results are presented

  17. Prevalence of antibodies to Trypanosoma cruzi, Toxoplasma gondii, Encephalitozonn cuniculi, Sarcocystis neurona, Besnoitia darlingi, and Neospora caninum in North American opossum, Didelphis virginiana, from Southern Louisian

    Science.gov (United States)

    We examined the prevalence of antibodies to zoonotic protozoan parasites (Trypanosoma cruzi, Toxoplasma gondii, and Encephalitozoon cuniculi) and protozoan’s of veterinary importance (Neospora caninum, Sarcocystis neurona and Besnoitia darlingi) in a population of North American opossums (Didelphis...

  18. Horses seropositive for Toxoplasma gondii, Sarcocystis spp. and Neospora spp.: Possible risk factors for infection in Brazil.

    Science.gov (United States)

    Cazarotto, Chrystian J; Balzan, Alexandre; Grosskopf, Rhayana K; Boito, Jhonatan P; Portella, Luiza P; Vogel, Fernanda F; Fávero, Juscivete F; de C Cucco, Diego; Biazus, Angelisa H; Machado, Gustavo; Da Silva, Aleksandro S

    2016-10-01

    Many parasitic diseases are considered asymptomatic, even though some studies have shown that they may cause pathological changes in the host. Therefore, the aim of this study was to evaluate the occurrence of antibodies against Toxoplasma gondii, Neospora spp. and Sarcocystis spp. in horses, and to identify the risk factors for disease. For this, 174 horses were studied, 90 males and 84 females aged between two and 20 years old. Blood samples were collected and stored in tubes without anticoagulant to obtain serum, which was subjected to serological tests for T. gondii, Sarcocystis spp., and Neospora spp. using indirect immunofluorescence assay (IFA). IFA results were as follows: Sarcocystis spp. 41.37% (72/174) (CI95%-34.05-49.09); T. gondii 32.18% (56/174) (CI95%-25.42-39.74) and Neospora spp. 48.27% (84/174) (CI95%-40.68.50-55.93). Out of 174 horses, 81 had simple infection, 61 had mixed infections with two or three of these pathogens, and therefore, only 32 horses showed no antibodies to any of these pathogens. No risk factors for Sarcocystis spp. and T. gondii infection were identified. However, there was a significant (1.22-CI95%-1.02-1.52) relationship between animal age and Neospora spp. infection, since older animals showed higher prevalence. Therefore, it was possible to conclude that T. gondii and Neospora spp. affect horses in Southern Brazil, however all the animals studied were asymptomatic without reproductive, neurological or locomotor problems. Copyright © 2016 Elsevier Ltd. All rights reserved.

  19. Cloning and characterization of two recombinant Neospora protein fragments and their use in serodiagnosis of bovine neosporosis.

    Science.gov (United States)

    Louie, K; Sverlow, K W; Barr, B C; Anderson, M L; Conrad, P A

    1997-01-01

    Bovine neosporosis causes fetal abortion and/or congenital neurologic disease in cattle. For the serodiagnosis of this parasitic disease, two immunodominant clones from a bovine Neospora lambda gt11 library were identified, characterized, and expressed as recombinant proteins for the development of an enzyme-linked immunosorbent assay (ELISA). These two clones, designated N54 and N57, were 29 and 20 kDa, respectively, when expressed as histidine fusion proteins from the pRSET expression vector. Antibodies to recombinant protein N54 recognized five major bands from a Neospora tachyzoite lysate with molecular masses of 97, 87, 77, 67, and 64 kDa. Antibodies to recombinant protein N57 recognized four primary bands with molecular masses of 34, 31, 30, and 28 kDa. When a defined "gold standard" panel of bovine sera from confirmed Neospora-positive and Neospora-negative cattle were characterized by immunoblotting, 57 of the 60 Neospora-positive serum samples recognized proteins with the molecular masses of the N54 heptuplet. Binding to the N57 quadruplet was more variable. The same gold standard panel was used to evaluate and compare an N54-based ELISA, an N57-based ELISA, and a whole-tachyzoite lysate-based ELISA. The sensitivities and specificities were 95 and 96% (N54 ELISA), 82 and 93% (N57 ELISA), and 74 and 93% (lysate ELISA). Thus, compared to the whole-tachyzoite lysate-based ELISA, both recombinant-protein-based ELISAs had higher sensitivities and higher or the same specificities and can be used to replace the whole-tachyzoite lysate ELISA for the serodiagnosis of bovine neosporosis. PMID:9384291

  20. Genome-scale comparison of expanded gene families in Plasmodium ovale wallikeri and Plasmodium ovale curtisi with Plasmodium malariae and with other Plasmodium species

    KAUST Repository

    Ansari, Hifzur Rahman

    2016-07-05

    Malaria in humans is caused by six species of Plasmodium parasites, of which the nuclear genome sequences for the two Plasmodium ovale spp., P. ovale curtisi and P. ovale wallikeri, and Plasmodium malariae have not yet been analyzed. Here we present an analysis of the nuclear genome sequences of these three parasites, and describe gene family expansions therein. Plasmodium ovale curtisi and P. ovale wallikeri are genetically distinct but morphologically indistinguishable and have sympatric ranges through the tropics of Africa, Asia and Oceania. Both P. ovale spp. show expansion of the surfin variant gene family, and an amplification of the Plasmodium interspersed repeat (pir) superfamily which results in an approximately 30% increase in genome size. For comparison, we have also analyzed the draft nuclear genome of P. malariae, a malaria parasite causing mild malaria symptoms with a quartan life cycle, long-term chronic infections, and wide geographic distribution. Plasmodium malariae shows only a moderate level of expansion of pir genes, and unique expansions of a highly diverged transmembrane protein family with over 550 members and the gamete P25/27 gene family. The observed diversity in the P. ovale wallikeri and P. ovale curtisi surface antigens, combined with their phylogenetic separation, supports consideration that the two parasites be given species status.

  1. Seroprevalence of Toxoplasma gondii and Neospora caninum in red deer from Central Italy

    Directory of Open Access Journals (Sweden)

    Guido Rocchigiani

    2016-09-01

    Full Text Available Neospora caninum and Toxoplasma gondii are cosmopolite protozoan parasites impacting on human and animal health. In particular, T. gondii commonly infects human beings and all warm-blooded animals, while N. caninum is responsible for bovine abortion and neuromuscular disease in dogs. The aim of the presented survey was to evaluate the occurrence and prevalence of these parasites in the most numerous Italian red deer population. The sera of 60 red deer ( Cervus elaphus inhabiting Central Italy (43°56’N 10°55’E and killed by selective hunting were examined using an indirect fluorescent antibody test (IFAT for both N. caninum and T. gondii antibodies. White blood cells (buffy coat were also checked by PCR and T. gondii DNA was genotyped. Thirteen out of 60 sera (22% scored positive for Toxoplasma, 17 samples (28% were Neospora positive. Coinfection was recorded in 5 cases (8%. T. gondii (genotype II and N. caninum DNA was detected in one and 3 samples of buffy coat, respectively. The presented study is the first to examine the occurrence of these parasites in the most numerous red deer Italian population, confirming this animal species as carrier of the investigated pathogens. These animals spread near human settlements, co-inhabiting with final hosts of [i]T. gondii[/i] and N. caninum and could contribute to their transmission to domestic ruminants and humans. In particular, the seroprevalence value for N. caninum was the highest among European records.

  2. Bottlenose dolphins (Tursiops truncatus do also cast neutrophil extracellular traps against the apicomplexan parasite Neospora caninum

    Directory of Open Access Journals (Sweden)

    R. Villagra-Blanco

    2017-12-01

    Full Text Available Neutrophil extracellular traps (NETs are web-like structures composed of nuclear DNA decorated with histones and cytoplasmic peptides which antiparasitic properties have not previously been investigated in cetaceans. Polymorphonuclear neutrophils (PMN were isolated from healthy bottlenose dolphins (Tursiops truncatus, and stimulated with Neospora caninum tachyzoites and the NETs-agonist zymosan. In vitro interactions of PMN with the tachyzoites resulted in rapid extrusion of NETs. For the demonstration and quantification of cetacean NETs, extracellular DNA was stained by using either Sytox Orange® or Pico Green®. Scanning electron microscopy (SEM and fluorescence analyses demonstrated PMN-derived release of NETs upon exposure to tachyzoites of N. caninum. Co-localization studies of N. caninum induced cetacean NETs proved the presence of DNA adorned with histones (H1, H2A/H2B, H3, H4, neutrophil elastase (NE, myeloperoxidase (MPO and pentraxin (PTX confirming the molecular properties of mammalian NETosis. Dolphin-derived N. caninum-NETosis were efficiently suppressed by DNase I and diphenyleneiodonium (DPI treatments. Our results indicate that cetacean-derived NETs represent an ancient, conserved and relevant defense effector mechanism of the host innate immune system against N. caninum and probably other related neozoan parasites circulating in the marine environment. Keywords: Tursiops truncatus, cetaceans, Neutrophil extracellular traps, Innate immunity, Neospora caninum.

  3. Neospora caninum in Wild Waterfowl: Occurrence of Parasite DNA and Low Antibody Titers.

    Science.gov (United States)

    Rocchigiani, G; Poli, A; Nardoni, S; Papini, R; Mancianti, F

    2017-02-01

    Thirty-five adult waterfowl (14 males and 21 females) representing various orders and species were sampled during the hunting season from 2015 to 2016. Antibodies to Neospora caninum were detected by IFAT on blood samples, while heart and brain were subjected to molecular analysis for the detection of Neospora caninum DNA. Twelve birds (34.3%) (6 Anas crecca , 3 Anas platyrhynchos , 2 Anas penelope , 1 Anas acuta ) showed antibodies versus N. caninum , while 10 animals out of 35 (4 A. crecca , 2 A. platyrhynchos , 2 A. penelope , 1 A. acuta , and 1 Vanellus vanellus ) scored positive for at least 1 DNA sample, with an overall prevalence of 28.6%. The present report shows for the first time the occurrence of antibodies and N. caninum DNA in waterfowl. The avian species investigated in the present report, which feed directly from the soil and/or water, would be able to ingest oocysts excreted by final canid hosts and could contribute to parasite transmission in the sylvatic cycle. To achieve a definitive result about the role of these avian species in the epidemiology of this protozoan, the presence of viable parasites should be demonstrated by bioassay and/or culture, as well as histological evidence of N. caninum cysts in avian tissues.

  4. Molecular detection of Neospora caninum from naturally infected dogs in Lorestan province, West of Iran

    Directory of Open Access Journals (Sweden)

    Dalimi, A.

    2014-11-01

    Full Text Available Neospora caninum is a coccidian protozoan that causes abortion in dairy and beef cattle and neurological disorders in dogs and horses. To identify N. caninum oocysts in the dog feces the molecular approaches are known as sensitive methods that specifically detect the oocysts. In present study, a polymerase chain reaction (PCR targeting N. caninum specific Nc5 genomic fragment was performed to identify the N. caninum DNA in the feces of naturally infected dogs of Lorestan province, West Iran. Fecal samples of dogs living in small dairy farms were collected. The samples were homogenized in 2.5% Potassium dichromate (K2Cr2O7 and stored at 4 °C. Genomic DNA was extracted from the feces using CTAB protocol. PCR assay and DNA sequencing were performed with specific primers. DNA amplification of the Nc5 formed a 340bp fragment for the N. caninum specimens; however, the fragment was 99% identical to the homologous sequences from Neospora caninum isolates. Totally, 9 positive samples of N. caninum were detected by PCR from 428 fecal specimens. 2.

  5. Isolation and molecular characterization of a new Neospora caninum isolate from cattle in Argentina.

    Science.gov (United States)

    Campero, L M; Venturini, M C; Moore, D P; Massola, L; Lagomarsino, H; García, B; Bacigalupe, D; Rambeaud, M; Pardini, L; Leunda, M R; Schares, G; Campero, C M

    2015-08-01

    Neospora caninum is one of the most important causes of bovine abortion, but isolation of live parasites from infected tissue is difficult. The aims of the present study were to obtain new isolates of N. caninum from congenitally infected asymptomatic newborn cattle in Argentina and to perform characterization by multilocus-microsatellite analysis. Five clinically normal born calves, with demonstrable N. caninum antibodies in precolostrum serum by indirect fluorescent antibody test, were euthanized and their brain samples were processed for histopathological, immunohistochemical, polymerase chain reaction (PCR) analysis, and for bioassay in γ-interferon knockout (GKO) mice. Although N. caninum DNA was detected in brain from all the calves by PCR, viable N. caninum was isolated in GKO mice from only one calf. Neospora caninum tachyzoites of this Argentinean isolate, designated NC-Argentina LP1, were propagated in VERO cell cultures seeded with tachyzoites from the infected GKO mice tissues. Multilocus-microsatellite typing on DNA derived from cell cultured tachyzoites revealed a unique genetic pattern, different from reported isolates. This is the first bovine isolation and genetic characterization of N. caninum in Argentina. Copyright © 2015 Elsevier Inc. All rights reserved.

  6. Seroprevalence of Neospora caninum Infection in Dairy Cattle in West of Iran

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    Hassan NAYEBZADEH

    2015-07-01

    Full Text Available The Neospora caninum parasite causes abortion in cattle in virtually all parts of the world with enormous economic consequences. The purpose of this study was to determine the seroprevalence of antibodies of Neospora caninum in dairy cattle in Lorestan Province, west of Iran. A total of 347 dairy cows were randomly selected. The serum of each case was analyzed for the possibility of the presence of antibody against N. caninum antigen, using the commercial kit: ELISA. The results of the ELISA test indicated that from 347 dairy cattle examined, the antibodies to N. caninum were found in 34 (9.8%. The percentage of seropositive aborted cattle was 13.33%. This study also indicated that there was no significant relationship between seropositivity and such factors as the age, breed, and abortion history of the cattle. Moreover, no significant relationship between seroprevalence of infection among rural and industrial cows was found. The neosporosis could be one of the possible causes of abortion in cattle. Further studies are recommended to determine the relationship between this parasite and the occurrence of abortion in cattle in the province of Lorestan.

  7. Plasmodium vivax Transmission in Africa.

    Directory of Open Access Journals (Sweden)

    Rosalind E Howes

    2015-11-01

    Full Text Available Malaria in sub-Saharan Africa has historically been almost exclusively attributed to Plasmodium falciparum (Pf. Current diagnostic and surveillance systems in much of sub-Saharan Africa are not designed to identify or report non-Pf human malaria infections accurately, resulting in a dearth of routine epidemiological data about their significance. The high prevalence of Duffy negativity provided a rationale for excluding the possibility of Plasmodium vivax (Pv transmission. However, review of varied evidence sources including traveller infections, community prevalence surveys, local clinical case reports, entomological and serological studies contradicts this viewpoint. Here, these data reports are weighted in a unified framework to reflect the strength of evidence of indigenous Pv transmission in terms of diagnostic specificity, size of individual reports and corroboration between evidence sources. Direct evidence was reported from 21 of the 47 malaria-endemic countries studied, while 42 countries were attributed with infections of visiting travellers. Overall, moderate to conclusive evidence of transmission was available from 18 countries, distributed across all parts of the continent. Approximately 86.6 million Duffy positive hosts were at risk of infection in Africa in 2015. Analysis of the mechanisms sustaining Pv transmission across this continent of low frequency of susceptible hosts found that reports of Pv prevalence were consistent with transmission being potentially limited to Duffy positive populations. Finally, reports of apparent Duffy-independent transmission are discussed. While Pv is evidently not a major malaria parasite across most of sub-Saharan Africa, the evidence presented here highlights its widespread low-level endemicity. An increased awareness of Pv as a potential malaria parasite, coupled with policy shifts towards species-specific diagnostics and reporting, will allow a robust assessment of the public health

  8. Natural infection of bats with Leishmania in Ethiopia.

    Science.gov (United States)

    Kassahun, Aysheshm; Sadlova, Jovana; Benda, Petr; Kostalova, Tatiana; Warburg, Alon; Hailu, Asrat; Baneth, Gad; Volf, Petr; Votypka, Jan

    2015-10-01

    The leishmaniases, a group of diseases with a worldwide-distribution, are caused by different species of Leishmania parasites. Both cutaneous and visceral leishmaniasis remain important public health problems in Ethiopia. Epidemiological cycles of these protozoans involve various sand fly (Diptera: Psychodidae) vectors and mammalian hosts, including humans. In recent years, Leishmania infections in bats have been reported in the New World countries endemic to leishmaniasis. The aim of this study was to survey natural Leishmania infection in bats collected from various regions of Ethiopia. Total DNA was isolated from spleens of 163 bats belonging to 23 species and 18 genera. Leishmania infection was detected by real-time (RT) PCR targeting a kinetoplast (k) DNA and internal transcribed spacer one (ITS1) gene of the parasite. Detection was confirmed by sequencing of the PCR products. Leishmania kDNA was detected in eight (4.9%) bats; four of them had been captured in the Aba-Roba and Awash-Methara regions that are endemic for leishmaniasis, while the other four specimens originated from non-endemic localities of Metu, Bedele and Masha. Leishmania isolates from two bats were confirmed by ITS1 PCR to be Leishmania tropica and Leishmania major, isolated from two individual bats, Cardioderma cor and Nycteris hispida, respectively. These results represent the first confirmed observation of natural infection of bats with the Old World Leishmania. Hence, bats should be considered putative hosts of Leishmania spp. affecting humans with a significant role in the transmission. Copyright © 2015 The Authors. Published by Elsevier B.V. All rights reserved.

  9. Prevalence of Neospora caninum antibodies in sheep flocks of Uberlândia county, MG Prevalência de anticorpos anti-Neospora caninum em rebanhos de ovinos do município de Uberlândia, MG

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    Sandra Renata Sampaio Salaberry

    2010-09-01

    Full Text Available Neosporosis is a parasitic disease that occurs in sheep and is associated with reproductive failure. The aim of this study was to verify seroprevalence of Neospora caninum antibodies in 12 sheep flocks in Uberlândia county, Minas Gerais, Brazil, using Indirect Immunofluorescence Assay (IFA. A total of 334 sheep blood samples were analyzed and an epidemiologic questionnaire was applied for each farm in order to correlate with risk factors of neosporosis: gender, age, breed, abortion problems, contact with cattle and dogs, and presence of wild canids. The prevalence of Neospora caninum antibodies in sheep was 8.1%, with titers ranging from 50 to 3200 and 83.3% of farms detected at least one ovine reactive. There was statistically significant difference in flocks with abortion problems associated with the presence of Neospora caninum antibodies (p A neosporose é uma doença parasitária que acomete os ovinos e está associada a perdas reprodutivas. O objetivo deste estudo foi verificar a prevalência de anticorpos anti-Neospora caninum em 12 rebanhos de ovinos do município de Uberlândia, MG, utilizando a Técnica de Imunofluorescência Indireta (RIFI. Foram analisadas 334 amostras de sangue e, em cada propriedade, aplicou-se um questionário epidemiológico para avaliar os fatores de risco envolvidos na transmissão desse protozoário: sexo, idade, raça, problemas de aborto, contato com bovinos e caninos e presença de canídeos silvestres. A prevalência de anticorpos anti-Neospora caninum em ovinos foi de 8,1%, com títulos variando de 50 a 3200 e 83,3% das propriedades apresentaram pelo menos um ovino reagente. Houve diferença estatística significativa para rebanhos com problemas de aborto associados à presença de anticorpos anti-Neospora caninum (p < 0,05.

  10. On Leishmania enriettii and Other Enigmatic Leishmania Species of the Neotropics

    Directory of Open Access Journals (Sweden)

    Ralph Lainson

    1997-05-01

    Full Text Available There are 20 named species of the genus Leishmania at present recognized in the New World, of which 14 are known to infect man. The present paper discusses the biological, biochemical and ecological features, where known, of six species which have not till now been found to cause human leishmaniasis; namely, Leishmania (Leishmania enriettii, L. (L. hertigi, L. (L. deanei, L. (L. aristidesi, L. (L. forattinii and L. (Viannia equatorensis. A protocol is suggested for attempts to discover the natural mammalian host(s and sandfly vector of L. (L. enriettii. Doubt is cast on the validity of the species L. herreri, described in Costa Rican sloths. Following the concensus of opinion that modern trypanosomatids derive from monogenetic intestinal flagellates of arthropods, phlebotomine sandflies are best regarded as the primary hosts of Leishmania species, with mammals acting as secondary hosts providing a source of parasites for these insects. There are probably natural barriers limiting the life-cycle of most leishmanial parasites to specific sandfly vectors

  11. [Importance of amastigote forms morphology to differentiate Leishmania infantum and Leishmania major species].

    Science.gov (United States)

    Aoun, K; Chahed, M K; Mokni, M; Harrat, Z; Bouratbine, A

    2003-01-01

    The microscopic study of the dermal smears of 62 cases of cutaneous leishmaniose, 27 infected by Leishmania (L.) infantum and 35 by L. major, showed that the amastigotes of L. infantum are meaningfully smaller (p < 0.001). This criteria is a simple pary alternative to distinguish these 2 species which have completely different epidemiology, recovery delay and prophylactic dispositions.

  12. A diagnostic assay based on variable intergenic region distinguishes between Leishmania donovani and Leishmania infantum

    Czech Academy of Sciences Publication Activity Database

    Chocholová, Eva; Jirků, Milan; Lukeš, Julius

    2008-01-01

    Roč. 55, č. 1 (2008), s. 75-78 ISSN 0015-5683 R&D Projects: GA MŠk LC07032; GA MŠk 2B06129 Institutional research plan: CEZ:AV0Z60220518 Keywords : Leishmania * assay * diagnosis Subject RIV: EB - Genetics ; Molecular Biology Impact factor: 1.307, year: 2008

  13. Molecular detection of Leishmania infection due to Leishmania major and Leishmania turanica in the vectors and reservoir host in Iran.

    Science.gov (United States)

    Rassi, Yavar; Oshaghi, Mohammad Ali; Azani, Sadegh Mohammadi; Abaie, Mohammad Reza; Rafizadeh, Sina; Mohebai, Mehdi; Mohtarami, Fatemeh; Zeinali, Mohammad kazem

    2011-02-01

    An epidemiological study was carried out on the vectors and reservoirs of cutaneous leishmaniasis in rural areas of Damghan district, Semnan province, central Iran, during 2008-2009. Totally, 6110 sand flies were collected using sticky papers and were subjected to molecular methods for detection of Leishmania parasite. Phlebotomus papatasi Scopoli was the common species in outdoor and indoor resting places. Polymerase chain reaction technique showed that 24 out of 218 P. papatasi (11%) and 4 out of 62 Phlebotomus caucasicus Marzinovskyi (6.5%) were positive for parasites Leishmania major Yakimoff and Schokhor. Twenty-one rodent reservoir hosts captured using Sherman traps were identified as Rhombomys opimus Lichtenstein (95%) and Meriones libycus Lichtenstein (5%). Microscopic investigation on blood smear of the animals for amastigote parasites revealed 8 (40%) rodents infected with R. opimus. L. major infection in these animals was then confirmed by polymerase chain reaction against internal transcribed spacer ribosomal DNA (rDNA) loci of the parasite followed by restriction fragment length polymorphism. Further, sequence analysis of 297 bp of ITS1-rDNA loci revealed the presence of L. major and Leishmania turanica in P. papatasi, and L. major in R. opimus. This is the first molecular report of L. major infection in both vectors (P. papatasi and P. caucasicus) and reservoir host (R. opimus) in this region. The results indicated that P. papatas was the primary vector of the disease and circulating the parasite between human and reservoirs, and P. caucasicus could be considered as a secondary vector. Further, our study showed that R. opimus is the most important host reservoir for maintenance of the parasite source in the area.

  14. Ocorrência de anticorpos anti-Neospora caninum em pequenas propriedades leiteiras do Uruguai Occurrence of anti-Neospora caninum antibodies in small dairy farms in Uruguay

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    Agustín Furtado

    2011-04-01

    Full Text Available Neosporose é uma doença de distribuição mundial causada por um protozoário (Apicomplexa, Sarcocystidae, denominado Neospora caninum (N. caninum. Na América Latina, o protozoário foi diagnosticado no Uruguai, Brasil, Argentina, Chile, Paraguai e Peru. No Uruguai a prevalência em rebanhos leiteiros não foi determinada, havendo somente levantamentos sorológicos de algumas regiões do país em propriedades rurais de médio e grande porte. O objetivo deste trabalho foi determinar a presença de animais sorologicamente positivos contra N. caninum em bacias leiteiras de pequenas propriedades com baixos recursos socioeconômicos da zona central do Uruguai (Estados de Durazno e Tacuarembó. Utilizando um Kit de ELISA comercial, foram analisados 734 soros provenientes de vacas leiteiras adultas, obtendo-se 211 positivos (28,8%, 517 negativos (70,5% e seis animais com resultado não determinado (0,7%. Nossos resultados demonstram a exposição destes rebanhos ao parasito, sendo este o primeiro inquérito sorológico de N. caninum em bacias leiteiras de pequenas propriedades no Uruguai.Neosporosis is a worldwide disease caused by a protozoan (Apicomplexa, Sarcocystidae, called Neospora caninum (N. caninum. In Latin America was diagnosed in Uruguay, Brazil, Argentina, Chile, Paraguay and Peru. In Uruguay, the prevalence in dairy cattle is undetermined, with only a few reports in some areas from medium and large farmers. The main of this study was to determine the presence of serologically positive animals against N. caninum in small dairy farmers in critical context from central region of Uruguay (Departments of Durazno and Tacuarembó. Using a commercial ELISA kit, 734 sera of adult dairy cows were analyzed, resulting in 211 positive (28.8%, 517 negative (70.5% and six animals with uncertain outcome (0.7%. The results demonstrated the exposure of cattle to the parasite, which is the first serological survey of N. caninum in basins of small dairy

  15. Detection and characterization of Leishmania (Leishmania and Leishmania (Viannia by SYBR green-based real-time PCR and high resolution melt analysis targeting kinetoplast minicircle DNA.

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    Marcello Ceccarelli

    Full Text Available Leishmaniasis is a neglected disease with a broad clinical spectrum which includes asymptomatic infection. A thorough diagnosis, able to distinguish and quantify Leishmania parasites in a clinical sample, constitutes a key step in choosing an appropriate therapy, making an accurate prognosis and performing epidemiological studies. Several molecular techniques have been shown to be effective in the diagnosis of leishmaniasis. In particular, a number of PCR methods have been developed on various target DNA sequences including kinetoplast minicircle constant regions. The first aim of this study was to develop a SYBR green-based qPCR assay for Leishmania (Leishmania infantum detection and quantification, using kinetoplast minicircle constant region as target. To this end, two assays were compared: the first used previously published primer pairs (qPCR1, whereas the second used a nested primer pairs generating a shorter PCR product (qPCR2. The second aim of this study was to evaluate the possibility to discriminate among subgenera Leishmania (Leishmania and Leishmania (Viannia using the qPCR2 assay followed by melting or High Resolution Melt (HRM analysis. Both assays used in this study showed good sensitivity and specificity, and a good correlation with standard IFAT methods in 62 canine clinical samples. However, the qPCR2 assay allowed to discriminate between Leishmania (Leishmania and Leishmania (Viannia subgenera through melting or HRM analysis. In addition to developing assays, we investigated the number and genetic variability of kinetoplast minicircles in the Leishmania (L. infantum WHO international reference strain (MHOM/TN/80/IPT1, highlighting the presence of minicircle subclasses and sequence heterogeneity. Specifically, the kinetoplast minicircle number per cell was estimated to be 26,566±1,192, while the subclass of minicircles amplifiable by qPCR2 was estimated to be 1,263±115. This heterogeneity, also observed in canine clinical

  16. Vaccines against a Major Cause of Abortion in Cattle, Neospora caninum Infection

    Science.gov (United States)

    Monney, Thierry; Debache, Karim; Hemphill, Andrew

    2011-01-01

    Simple Summary We review the efforts to develop a vaccine against neosporosis, caused by the apicomplexan parasite Neospora caninum. Vertical transmission is the main mode of infection, and can lead to stillbirth, abortion, or birth of weak calves. We provide information on the biology of Neospora caninum and on the disease caused by this parasite, and summarize the current understanding on how the host deals with infection. We review studies on live- and subunit-vaccines, and demonstrate advantages and setbacks in the use of small laboratory animal models in investigations on a disease with high relevance in cattle. Abstract Neosporosis, caused by the apicomplexan parasite Neospora caninum, represents one of the economically most important causes of abortion in cattle. During pregnancy, the parasite infects the placental tissue and the fetus, which can lead to stillbirth, abortion, or birth of weak calves. Alternatively, calves are born without clinical symptoms, but they can carry over the parasite to the next generation. In addition, N. caninum causes neuromuscular disease in dogs. The economic importance of neosporosis has prompted researchers to invest in the development of measures to prevent infection of cattle by vaccination. A good vaccine must stimulate protective cellular immune responses as well as antibody responses at mucosal sites and, systemically, must activate T-helper cells to produce relevant cytokines, and must elicit specific antibodies that aid in limiting parasite proliferation, e.g., by interference with host cell invasion, activation of complement, and/or opsonization of parasites to have them killed by macrophages. Different types of vaccines have been investigated, either in bovines or in the mouse model. These include live vaccines such as naturally less virulent isolates of N. caninum, attenuated strains generated by irradiation or chemical means, or genetically modified transgenic strains. Live vaccines were shown to be very effective

  17. Histopatologia da forma localizada de leishmaniose cutânea por Leishmania (Leishmania amazonensis Histopathology of the localized form of cutaneous leishmaniasis due to Leishmania (Leishmania amazonensis

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    Mário A. P. Moraes

    1994-10-01

    Full Text Available São descritas as alterações microscópicas presentes na forma localizada (ulcerada da Leishmaniose cutânea produzida por Leishmania (Leishmania amazonensis. Nesse tipo de manifestação, menos conhecido do que a forma anérgica ou difusa devida ao mesmo agente, as lesões são clinicamente idênticas às de leishmaniose cutânea causada por espécies outras de Leishmania, pertencentes ao subgênero Viannia. Na infecção localizada por L. (L. amazonensis, entretanto, há um aspecto peculiar, só recentemente conhecido, ou seja, cerca de 50% dos indivíduos atingidos não reagem ao teste de Montenegro. A principal característica histológica observada foi a acumulação na derme, quase sempre focal, de numerosos macrófagos contendo no citoplasma um grande vacúolo cheio de amastigotas. O quadro é semelhante ao da forma difusa, porém sem o aspecto histiocitomatóide, próprio da última. Afora esses grupos de macrófagos, vêem-se também, na forma localizada, muitas células mononucleares da inflamação, principalmente plasmócitos e macrófagos não parasitados. Os acúmulos de macrófagos com amastigotas, quando volumosos, podem sofrer necrose na parte central; os parasitos, contidos nas células, são destruídos com elas ou liberados, e sua eliminação através da úlcera deve contribuir para a cura do processo. Esse tipo de necrose nunca foi descrito em casos da forma difusa. Não houve grande diferença, no quadro histológico, entre pacientes Montenegro-negativos e positivos. Apenas em alguns casos, do grupo Montenegro-positivo, havia granulomas formados por histiócitos epitelióides sem parasitos. Quanto à persistência das células com parasitos nas lesões, observou-se que aos seis meses ou mais de evolução, em ambos os grupos, ainda estavam elas presentes. Tal achado não é comum na leishmaniose tegumentar por L. (V. braziliensis.The microscopic changes found in the localized form of the human cutaneous leishmaniasis due

  18. Distinct Macrophage Fates after in vitro Infection with Different Species of Leishmania: Induction of Apoptosis by Leishmania (Leishmania amazonensis, but Not by Leishmania (Viannia guyanensis.

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    Jarina Pena DaMata

    Full Text Available Leishmania is an intracellular parasite in vertebrate hosts, including man. During infection, amastigotes replicate inside macrophages and are transmitted to healthy cells, leading to amplification of the infection. Although transfer of amastigotes from infected to healthy cells is a crucial step that may shape the outcome of the infection, it is not fully understood. Here we compare L. amazonensis and L. guyanensis infection in C57BL/6 and BALB/c mice and investigate the fate of macrophages when infected with these species of Leishmania in vitro. As previously shown, infection of mice results in distinct outcomes: L. amazonensis causes a chronic infection in both strains of mice (although milder in C57BL/6, whereas L. guyanensis does not cause them disease. In vitro, infection is persistent in L. amazonensis-infected macrophages whereas L. guyanensis growth is controlled by host cells from both strains of mice. We demonstrate that, in vitro, L. amazonensis induces apoptosis of both C57BL/6 and BALB/c macrophages, characterized by PS exposure, DNA cleavage into nucleosomal size fragments, and consequent hypodiploidy. None of these signs were seen in macrophages infected with L. guyanensis, which seem to die through necrosis, as indicated by increased PI-, but not Annexin V-, positive cells. L. amazonensis-induced macrophage apoptosis was associated to activation of caspases-3, -8 and -9 in both strains of mice. Considering these two species of Leishmania and strains of mice, macrophage apoptosis, induced at the initial moments of infection, correlates with chronic infection, regardless of its severity. We present evidence suggestive that macrophages phagocytize L. amazonensis-infected cells, which has not been verified so far. The ingestion of apoptotic infected macrophages by healthy macrophages could be a way of amastigote spreading, leading to the establishment of infection.

  19. The SNARE protein family of Leishmania major

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    Mottram Jeremy C

    2006-10-01

    Full Text Available Abstract Background Leishmania major is a protozoan parasite with a highly polarised cell shape that depends upon endocytosis and exocytosis from a single area of the plasma membrane, the flagellar pocket. SNAREs (soluble N-ethylmaleimide-sensitive factor adaptor proteins receptors are key components of the intracellular vesicle-mediated transports that take place in all eukaryotic cells. They are membrane-bound proteins that facilitate the docking and fusion of vesicles with organelles. The recent availability of the genome sequence of L. major has allowed us to assess the complement of SNAREs in the parasite and to investigate their location in comparison with metazoans. Results Bioinformatic searches of the L. major genome revealed a total of 27 SNARE domain-containing proteins that could be classified in structural groups by phylogenetic analysis. 25 of these possessed the expected features of functional SNAREs, whereas the other two could represent kinetoplastid-specific proteins that might act as regulators of the SNARE complexes. Other differences of Leishmania SNAREs were the absence of double SNARE domain-containing and of the brevin classes of these proteins. Members of the Qa group of Leishmania SNAREs showed differential expressions profiles in the two main parasite forms whereas their GFP-tagging and in vivo expression revealed localisations in the Golgi, late endosome/lysosome and near the flagellar pocket. Conclusion The early-branching eukaryote L. major apparently possess a SNARE repertoire that equals in number the one of metazoans such as Drosophila, showing that the machinery for vesicle fusion is well conserved throughout the eukaryotes. However, the analysis revealed the absence of certain types of SNAREs found in metazoans and yeast, while suggesting the presence of original SNAREs as well as others with unusual localisation. This study also presented the intracellular localisation of the L. major SNAREs from the Qa group

  20. Comment on ?Regulation of immunity during visceral Leishmania infection? and further discussions about the role of antibodies in infections with Leishmania

    OpenAIRE

    Gardinassi, Luiz Gustavo; de Miranda Santos, Isabel Kinney Ferreira

    2016-01-01

    Abstract Comments on the article “Regulation of immunity during visceral Leishmania infection” published in Parasites & Vectors 2016, 9:118, and further discussions about the role of antibodies in infections with Leishmania.

  1. Comment on "Regulation of immunity during visceral Leishmania infection" and further discussions about the role of antibodies in infections with Leishmania.

    Science.gov (United States)

    Gardinassi, Luiz Gustavo; de Miranda Santos, Isabel Kinney Ferreira

    2016-07-07

    Comments on the article "Regulation of immunity during visceral Leishmania infection" published in Parasites & Vectors 2016, 9:118, and further discussions about the role of antibodies in infections with Leishmania.

  2. Detection of Neospora sp. antibodies in cart horses from urban areas of Curitiba, Southern Brazil Detecção de anticorpos anti-Neospora sp. em cavalos de carroceiros de áreas urbanas de Curitiba, Sul do Brasil

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    Eliana Monteforte Cassaro Villalobos

    2012-03-01

    Full Text Available Neospora caninum is a protozoan parasite which affects dogs as definitive hosts and several mammalian species as intermediate hosts mainly causing abortions and central nervous system disorders. The reemerging population of cart horses for carrying recycling material in urban areas of major cities in Brazil may have an impact on disease spreading, and these animals may be used as sentinels for environmental surveillance. Thus, the present study investigated the frequency of Neospora sp. antibodies in cart horses from Curitiba and surrounding areas, Paraná State, Southern Brazil. IgG antibodies against Neospora sp. were detected using indirect fluorescence antibody test (IFAT, and titers equal to or higher than 1:50 were considered reactive. Of all samples, 14/97 (14.4% were positive: 2/29 (6.9% were younger than 5; 5/26 (19.2% between 6 and 9; and 6/31 (19.4% older than 10 years of age. One of the 11 animals with unknown age was positive (9.1%. Cart horses are likely to be more exposed to dog feces and to Neospora sp. oocyst contamination in urban settings and a lower frequency of disease in dogs may have a negative impact on horse infection risk in these areas.Neospora caninum é um protozoário parasita que afeta cães como hospedeiros definitivos e diversos mamíferos como hospedeiros intermediários, envolvido em abortos e distúrbios do sistema nervoso central. A população reemergente de cavalos de carroceiros utilizados para transportar material reciclável em áreas urbanas de grandes cidades brasileiras na disseminação de doenças, e estes animais podem ser utilizados como sentinelas para vigilância ambiental. Deste modo, no presente estudo foi investigada a frequência de anticorpos anti-Neospora sp. em cavalos de carroceiros da Região Metropolitana de Curitiba, Estado do Paraná, Sul do Brasil. Anticorpos da classe IgG anti-Neospora sp. foram detectados utilizando a reação de imunofluorescência indireta (RIFI, e t

  3. Molecular identification of Leishmania species in Taybad district, Iran

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    Salehi Ghodratollah

    2014-09-01

    Full Text Available Objective: To identify Leishmania species in patients with cutaneous leishmaniasis in the city of Taybad in Razavi Khorasan Province from April 2012 to March 2013. Methods: Among 52 persons who referred to Health Center of Taybad with suspected skin lesions, stained slide smears of 35 patients showed positive result for Leishmania. Also polymerase chain reaction assay performed using specific kDNA primers. Data of patients were analyzed with SPSS. Results: Of 35 positive smears for Leishmania, 21 (60% belonged to males and 14 (40% belonged to females. Polymerase chain reaction bands were observed in all 35 samples of which 31 (88.6% samples showed Leishmania tropica and 4 (11.4% showed Leishmania major. The highest infected age group was 11-20 years old. Conclusions: Both anthroponotic cutaneous leishmaniasis and zoonotic cutaneous leishmaniasis are present in Taybad. Leishmania tropica is the dominant causative species for anthroponotic cutaneous leishmaniasis. Further study is recommended to discover probable reservoir and vector for Leishmania major in Taybad.

  4. Essential oil from Chenopodium ambrosioides and main components: activity against Leishmania, their mitochondria and other microorganisms.

    Science.gov (United States)

    Monzote, Lianet; García, Marley; Pastor, Jacinta; Gil, Lizette; Scull, Ramón; Maes, Louis; Cos, Paul; Gille, Lars

    2014-01-01

    Chenopodium ambrosioides is an aromatic herb used by native people to treat parasitic diseases. The aim of this work is to compare the in vitro anti-leishmanial activity of the essential oil (EO) from C. ambrosioides and its major components (ascaridole, carvacrol and caryophyllene oxide) and study their mechanism of action and activity against a panel of microorganism. Antileishmanial activity and cytotoxicity of the EO and major components was study. In addition, experiments to elucidate the mechanism of action were perform and activities against other microorganisms (bacteria, fungi and protozoa) were evaluate. All products were active against promastigote and amastigote forms of Leishmania. Ascaridole exhibited the better antileishmanial activity and the EO the highest selectivity index. The exploration of the mechanism suggests that the products cause a breakdown of mitochondrial membrane potential and a modification of redox indexes. Only EO showed antiprotozoal effect against Plasmodium falciparum and Trypanosoma brucei; while no activity against bacteria and fungi was observed. Our results demonstrate the potentialities of EO in cellular and molecular system, which could be consider in future studies to develop new antileishmanial drugs with a wide anti-parasitic spectrum. Copyright © 2013 Elsevier Inc. All rights reserved.

  5. Evaluation of methylene blue, pyrimethamine and its combination on an in vitro Neospora caninum model.

    Science.gov (United States)

    Pereira, Luiz Miguel; Vigato-Ferreira, Isabel Cristina; DE Luca, Gabriela; Bronzon DA Costa, Cássia Mariana; Yatsuda, Ana Patrícia

    2017-05-01

    Neospora caninum is an apicomplexan parasite strongly related to reproductive problems in cattle. The neosporosis control is not well established and several fronts are under development, predominantly based on immune protection, immunomodulation and chemotherapy. The use of anti-malarial drugs as therapeutic sources has, in theory, considerable potential for any apicomplexan. Drugs such as methylene blue (MB) and pyrimethamine (Pyr) represent therapeutic options for malaria; thus, their use for neosporosis should be assessed. In this work, we tested the effects of MB and Pyr on N. caninum proliferation and clearance, using LacZ-tagged tachyzoites. The drugs inhibited at nanomolar dosages and its combination demonstrated an antagonistic interaction in proliferation assays, according to the Chou and Talalay method for drug combination index. However, the drug combination significantly improved the parasite in vitro clearance. The repositioning of well-established drugs opens a short-term strategy to obtain low-cost therapeutics approaches against neosporosis.

  6. Prevalence and correlates of antibodies to Neospora caninum in dogs in Portugal

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    Maia Carla

    2014-01-01

    Full Text Available Neosporosis, caused by Neospora caninum, is an important cause of abortion in cattle and of neurological disease in dogs. This study investigated the prevalence and correlates of antibodies to N. caninum in 441 dogs from the five regions of mainland Portugal. A commercial competitive enzyme-linked immunosorbent assay (cELISA was used and specific antibodies were detected in 35 (7.9% dogs. Seroprevalence levels were significantly different among some of the studied regions, as well as between stray dogs (13.6% and hunting dogs (1.7%. The difference between seropositivity in dogs presenting musculoskeletal or neurological signs (21.4% and that in animals without clinical signs compatible with neosporosis (5.6% was close to statistical significance. This is the first report on the seroprevalence of N. caninum in dogs in Portugal. Neosporosis should be considered in the differential diagnosis of neurological disorders of dogs.

  7. Seroprevalence of Neospora caninum in feral swine (Sus scrofa) in the United States.

    Science.gov (United States)

    Cerqueira-Cézar, Camila K; Pedersen, Kerri; Calero-Bernal, Rafael; Kwok, Oliver C; Villena, Isabelle; Dubey, Jitender P

    2016-08-15

    The protozoon Neospora caninum is a major cause of abortion in cattle worldwide. Canids (Canis familiaris, Canis latrans, Canis lupus) are definitive hosts whereas many other animal species, including pigs, are intermediate hosts for the parasite. Between 2012 and 2014, serum samples from 1059 feral swine (Sus scrofa) from 29 states of the USA were tested for N. caninum antibodies, using the N. caninum agglutination test (NAT). Of these, 159 (15.0%) feral pigs from 21 states tested positive, with a range of titers of 1:25 (cut-off) (n=153), 1:200 (1), 1:400 (1), 1:800 (3) and 1:3200 (1). Results indicate widespread exposure of feral swine to N. caninum infection across the USA. Published by Elsevier B.V.

  8. The p38 MAPK inhibitor, SB203580, inhibits cell invasion by Neospora caninum.

    Science.gov (United States)

    Jin, Xiaoxia; Gong, Pengtao; Li, Guojiang; Zhang, Xichen; Li, Jianhua

    2017-02-01

    The Apicomplexan parasite Neospora caninum is an obligate intracellular parasitic protozoan. It can cause severe diseases in a number of animals throughout the world. Infection with N. caninum leads to abortions in pregnant animals and neuromuscular disorders of newborns which cause great economic losses to animal husbandry. However, the mechanism of cell invasion by N. caninum is still unclear. This paper aims to investigate the impact of SB203580, a p38 MAPK inhibitor, on host cell invasion by N. caninum. The results suggested the presence of putative p38 MAPK homologues in N. caninum, and incubation of N. caninum with SB203580 markedly reduced the tachyzoite motility and microneme exocytosis (NcMIC2, 3, and 6). Furthermore, treatment or pretreatment of MDBK cells with SB203580 effectively reduced cell invasion by N. caninum. Therefore, SB203580 affected both, parasites and host cells, resulting in inhibition of cell invasion by N. caninum.

  9. Seroprevalence of and risk factors for Neospora caninum infection in yaks (Bos grunniens) in China.

    Science.gov (United States)

    Meng, Qing-Feng; Yao, Gui-Zhe; Qin, Si-Yuan; Wu, Jian; Zhang, Xi-Chen; Bai, Ya-Duo; Cong, Wei; Wang, Wei-Li

    2017-08-15

    The aim of the present study was to detect the seroprevalence of Neospora caninum infection in yaks in Gansu province, China. Serum samples from 974 white yaks and 610 black yaks were tested by a commercial competitive-inhibition ELISA for the detection of specific anti-N. caninum antibodies.; N. caninum antibodies were detected in 10.4% of yaks with higher prevalence in black (11.5% of 610) than white yak (8.6% of 974). Age, regions and sampling times were considered as risk factors associated with N. caninum infection. These results revealed the seroprevalence of N. caninum in white yaks for the first time in China. Copyright © 2017 Elsevier B.V. All rights reserved.

  10. Serological investigation of transplacental infection with Neospora hughesi and Sarcocystis neurona in broodmares.

    Science.gov (United States)

    Pusterla, Nicola; Mackie, Sarah; Packham, Andrea; Conrad, Patricia A

    2014-12-01

    The aim of the present study was to investigate the likelihood of transplacental transmission of Neospora hughesi and Sarcocystis neurona in foals, born from seropositive mares. Three broodmares with persistent N. hughesi infection gave birth to eight healthy foals over a period of 7 years. These foals were seropositive to N. hughesi prior to colostrum ingestion, with titers ranging between 640 and 20,480, measured by indirect fluorescence antibody test (IFAT). Of 174 foals born at another farm to mares with a high seroprevalence to S. neurona, only one (with a pre-colostrum antibody titer of 80) tested seropositive. Transplacental transmission of N. hughesi seems to occur from latently infected mares to their foals, while this route of transmission does not seem to occur commonly for S. neurona. Copyright © 2014 Elsevier Ltd. All rights reserved.

  11. Isolation of viable Neospora caninum from brains of wild gray wolves (Canis lupus).

    Science.gov (United States)

    Dubey, J P; Jenkins, M C; Ferreira, L R; Choudhary, S; Verma, S K; Kwok, O C H; Fetterer, R; Butler, E; Carstensen, M

    2014-03-17

    Neospora caninum is a common cause of abortion in cattle worldwide. Canids, including the dog and the dingo (Canis familiaris), the coyote (Canis latrans), and the gray wolf (Canis lupus) are its definitive hosts that can excrete environmentally resistant oocysts in the environment, but also can act as intermediate hosts, harboring tissue stages of the parasite. In an attempt to isolate viable N. caninum from tissues of naturally infected wolves, brain and heart tissue from 109 wolves from Minnesota were bioassayed in mice. Viable N. caninum (NcWolfMn1, NcWolfMn2) was isolated from the brains of two wolves by bioassays in interferon gamma gene knockout mice. DNA obtained from culture-derived N. caninum tachyzoites of the two isolates were analyzed by N. caninum-specific Nc5 polymerase chain reaction and confirmed diagnosis. This is the first report of isolation of N. caninum from tissues of any wild canid host. Published by Elsevier B.V.

  12. Seroprevalence and risk factors for Neospora caninum in goats in Santa Catarina state, Brazil

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    Josué Pires Topazio

    Full Text Available Neosporosis is an infectious disease caused by the parasite Neospora caninum. Knowledge regarding neosporosis in goats is still quite limited, especially in the state of Santa Catarina (SC, southern Brazil. Therefore, this study aimed to assess the seroprevalence and risk factors for N. caninum in goats in the western and mountain regions of SC. Blood samples were collected from 654 goats in 57 municipalities. The indirect immunofluorescence test was used for antibody detection against N. caninum. Thirty samples (4.58% were seropositive, with titers ranging from 1:50 to 1:6400. An epidemiological survey was also conducted in order to identify risk factors for neosporosis in goats. It was found that reproductive problems on the farms, as well as the diet and direct contact with dogs were casual risks for neosporosis. These results indicate that N. caninum infects goats in these regions, which may lead to reproductive problems.

  13. Neospora caninum: analysis of reproductive parameters in dairy herds in Brazil

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    José Márcio Sbruzzi Cardoso

    2012-12-01

    Full Text Available Neosporosis is one of the most important causes of abortion in both dairy and beef cattle in many countries. The objective of this study was to quantify the effect of Neospora caninum seropositivity on reproductive parameters in three dairy herds and the dynamics of anti-N. caninum antibodies during gestation in naturally infected cows. Blood samples from all animals were collected nine times on each of the three farms over a two-year period. Serum was tested for antibodies against N. caninum using the indirect fluorescent antibody test (IFAT with a cutoff value of 1:100. The relative risk of abortion between N. caninum-seropositive and seronegative cows varied between samplings at all farms, but there was only a statistically significant difference (P0.05 were found regarding gestational age at abortion, repeated abortion, number of inseminations for conception and calving intervals, between seropositive and seronegative cows on all the farms.

  14. Seroprevalence of Neospora caninum Infection in Dairy Cattle in Tabriz, Northwest Iran

    Science.gov (United States)

    Nematollahi, A; Jaafari, R; Moghaddam, Gh

    2011-01-01

    Background The aim of this study was to determine the seroprevalence of antibody to Neospora caninum in healthy and aborted dairy cattle in Tabriz, capital of East-Azarbaijan in northwest of Iran. Methods In this cross-sectional study serum samples were collected from 266 healthy and aborted Holestein-Feriesisnc cows from September 2008 to August 2009. The sera were analyzed to detect of antibody against N. caninum using the commercially ELISA kit. Results Seroprevalence of antibody to N. caninum was 10.5% in Tabriz dairy cattle. Also the abortion rate in all cattle sampled was 33.6% but percentage of seropositive aborted cattle was 18.4%. Conclusion Neosporosis could be one of the possible causes of abortion in dairy cattle in Tabriz and regarding the distribution in dogs as definitive host for the parasite, further studies in dog and cattle are recommended. PMID:22347319

  15. Virulence assessment of a Neospora caninum isolate for inbred C57BL/6 mouse

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    Lotfi, M.

    2012-06-01

    Full Text Available Neospora caninum (N. caninum is an apicomplexan parasite and causes abortion and congenital neosporosis in cattle worldwide. In this study, we evaluate the virulence of a N. caninum isolate on mouse strain C57BL/6. Six groups of five mice C57BL/6 were intraperitoneally inoculated with 1 × l07, 1.5 × l07, 2 × l07, 3 × l07 and 4 × l07 tachyzoites and a control inoculum of DMEM, respectively. Clinical signs and mortality rate were recorded and confirmed by histopathological findings and molecular method. The results of this study indicated that LD50 was 2.5 × l07 tachyzoites of N. caninum per C57BL/6 mouse. This can be used as a lethal challenge model in vaccine development studies.

  16. Prevalence and correlates of antibodies to Neospora caninum in dogs in Portugal

    Science.gov (United States)

    Maia, Carla; Cortes, Helder; Brancal, Hugo; Lopes, Ana Patrícia; Pimenta, Paulo; Campino, Lenea; Cardoso, Luís

    2014-01-01

    Neosporosis, caused by Neospora caninum, is an important cause of abortion in cattle and of neurological disease in dogs. This study investigated the prevalence and correlates of antibodies to N. caninum in 441 dogs from the five regions of mainland Portugal. A commercial competitive enzyme-linked immunosorbent assay (cELISA) was used and specific antibodies were detected in 35 (7.9%) dogs. Seroprevalence levels were significantly different among some of the studied regions, as well as between stray dogs (13.6%) and hunting dogs (1.7%). The difference between seropositivity in dogs presenting musculoskeletal or neurological signs (21.4%) and that in animals without clinical signs compatible with neosporosis (5.6%) was close to statistical significance. This is the first report on the seroprevalence of N. caninum in dogs in Portugal. Neosporosis should be considered in the differential diagnosis of neurological disorders of dogs. PMID:24972327

  17. Neospora caninum calcium-dependent protein kinase 1 is an effective drug target for neosporosis therapy.

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    Kayode K Ojo

    Full Text Available Despite the enormous economic importance of Neospora caninum related veterinary diseases, the number of effective therapeutic agents is relatively small. Development of new therapeutic strategies to combat the economic impact of neosporosis remains an important scientific endeavor. This study demonstrates molecular, structural and phenotypic evidence that N. caninum calcium-dependent protein kinase 1 (NcCDPK1 is a promising molecular target for neosporosis drug development. Recombinant NcCDPK1 was expressed, purified and screened against a select group of bumped kinase inhibitors (BKIs previously shown to have low IC50s against Toxoplasma gondii CDPK1 and T. gondii tachyzoites. NcCDPK1 was inhibited by low concentrations of BKIs. The three-dimensional structure of NcCDPK1 in complex with BKIs was studied crystallographically. The BKI-NcCDPK1 structures demonstrated the structural basis for potency and selectivity. Calcium-dependent conformational changes in solution as characterized by small-angle X-ray scattering are consistent with previous structures in low Calcium-state but different in the Calcium-bound active state than predicted by X-ray crystallography. BKIs effectively inhibited N. caninum tachyzoite proliferation in vitro. Electron microscopic analysis of N. caninum cells revealed ultra-structural changes in the presence of BKI compound 1294. BKI compound 1294 interfered with an early step in Neospora tachyzoite host cell invasion and egress. Prolonged incubation in the presence of 1294 interfered produced observable interference with viability and replication. Oral dosing of BKI compound 1294 at 50 mg/kg for 5 days in established murine neosporosis resulted in a 10-fold reduced cerebral parasite burden compared to untreated control. Further experiments are needed to determine the PK, optimal dosage, and duration for effective treatment in cattle and dogs, but these data demonstrate proof-of-concept for BKIs, and 1294 specifically, for

  18. Toltrazuril treatment of congenitally acquired Neospora caninum infection in newborn mice.

    Science.gov (United States)

    Strohbusch, M; Müller, N; Hemphill, A; Krebber, R; Greif, G; Gottstein, B

    2009-06-01

    C57BL/6 mice were infected with Neospora caninum tachyzoites during pregnancy, yielding a transplacental infection of developing fetuses. Subsequently, congenitally infected newborn mice were treated either once or three times with toltrazuril (or placebo) at a concentration of 31.25 mg compound per kg body weight. Both toltrazuril and placebo treatment had no negative effect on newborns, as noninfected treated pups developed normally without differences in mortality and morbidity to matching nontreated control animals. Already one application of toltrazuril was significantly (p toltrazuril-treated and three-time-toltrazuril-treated groups (34% and 54%, respectively) when compared to one-time-placebo-treated and three-time-placebo-treated groups (14% and 30%, respectively). There was no significant difference (p = 0.2) in the proportion of surviving pups between one-time-toltrazuril and three-time-toltrazuril treatment. However, the number of diseased and Neospora-positive pups (46% and 47%, respectively) was markedly reduced after three-time-toltrazuril treatment compared to all other groups. Three-time-treatment also resulted in the highest antibody (IgG, IgG2a) response. Pharmacokinetic analyses using individual serum samples revealed that, although toltrazuril was absorbed and metabolized to toltrazuril sulfone by newborn mice, medicated animals exhibited an unexpected rapid turn-over (half-life time) of the compound. Toltrazuril and the metabolite were also found in brain tissues, indicating that passage of the blood-brain barrier occurred. In conclusion, we could show that three times treatment with toltrazuril had a high impact on the course of infection in congenitally N. caninum-infected newborn mice.

  19. A review of neosporosis and pathologic findings of Neospora caninum infection in wildlife

    Science.gov (United States)

    Donahoe, Shannon L.; Lindsay, Scott A.; Krockenberger, Mark; Phalen, David; Šlapeta, Jan

    2015-01-01

    Neospora caninum is an apicomplexan parasite that is the etiologic agent of neosporosis, a devastating infectious disease regarded as a major cause of reproductive loss in cattle and neuromuscular disease in dogs worldwide. This protozoan pathogen is maintained in the environment by a heteroxenous life cycle that involves a definitive canid host and a wide range of intermediate hosts. In recent years, a number of wildlife species have been investigated for their possible involvement in the N. caninum life cycle and many have been implicated as intermediate hosts. However, in many instances these studies have utilized serological and molecular techniques to detect infection in clinically normal animals, and investigation of possible associated morbidity, mortality, and pathology has been neglected. As such, the occurrence and importance of Neospora-associated disease in wildlife species are unknown. In order to improve our understanding of the significance of N. caninum infection in nondomestic species, the present review provides an up-to-date summary of clinical neosporosis and N. caninum-associated pathologic lesions in naturally and experimentally infected wildlife species. We provide a list of all free-ranging and captive wildlife species identified with N. caninum infection to date using currently available diagnostic tools. The advantages and disadvantages of diagnostic methods in wildlife are addressed in order to recommend optimal diagnosis of confirming N. caninum infection and neosporosis in nondomestic species. Although current data would suggest that N. caninum infection does not adversely impact wildlife populations, there is a need for greater international uniformity in the diagnosis of N. caninum infection and neosporosis in nondomestic species in order to assess the true consequences of parasite infection. PMID:25973393

  20. A review of neosporosis and pathologic findings of Neospora caninum infection in wildlife

    Directory of Open Access Journals (Sweden)

    Shannon L. Donahoe

    2015-08-01

    Full Text Available Neospora caninum is an apicomplexan parasite that is the etiologic agent of neosporosis, a devastating infectious disease regarded as a major cause of reproductive loss in cattle and neuromuscular disease in dogs worldwide. This protozoan pathogen is maintained in the environment by a heteroxenous life cycle that involves a definitive canid host and a wide range of intermediate hosts. In recent years, a number of wildlife species have been investigated for their possible involvement in the N. caninum life cycle and many have been implicated as intermediate hosts. However, in many instances these studies have utilized serological and molecular techniques to detect infection in clinically normal animals, and investigation of possible associated morbidity, mortality, and pathology has been neglected. As such, the occurrence and importance of Neospora-associated disease in wildlife species are unknown. In order to improve our understanding of the significance of N. caninum infection in nondomestic species, the present review provides an up-to-date summary of clinical neosporosis and N. caninum-associated pathologic lesions in naturally and experimentally infected wildlife species. We provide a list of all free-ranging and captive wildlife species identified with N. caninum infection to date using currently available diagnostic tools. The advantages and disadvantages of diagnostic methods in wildlife are addressed in order to recommend optimal diagnosis of confirming N. caninum infection and neosporosis in nondomestic species. Although current data would suggest that N. caninum infection does not adversely impact wildlife populations, there is a need for greater international uniformity in the diagnosis of N. caninum infection and neosporosis in nondomestic species in order to assess the true consequences of parasite infection.

  1. Neospora caninum is the leading cause of bovine fetal loss in British Columbia, Canada

    Science.gov (United States)

    Wilson, Devon J; Orsel, Karin; Waddington, Josh; Rajeev, Malavika; Sweeny, Amy R.; Joseph, Tomy; Grigg, Michael E; Raverty, Stephen A.

    2016-01-01

    The protozoan pathogen Neospora caninum is recognized as a leading cause of infectious abortions in cattle worldwide. To evaluate the impact of neosporosis on dairy and beef herd production, a retrospective, longitudinal study was performed to identify the impact of neosporosis alongside other causes of fetal abortion in British Columbia, Canada. Retrospective analysis of pathology records of bovine fetal submissions submitted to the Animal Health Centre, Abbotsford, British Columbia, a provincial veterinary diagnostic laboratory, from January 2007– July 2013 identified 182 abortion cases (passive surveillance). From July 2013–May 2014, an active surveillance program identified a further 54 abortion cases from dairy farmers in the Upper Fraser Valley, British Columbia. Of the total 236 fetal submissions analyzed, N. caninum was diagnosed in 18.2% of cases, making it the most commonly identified infectious agent associated with fetal loss. During active surveillance, N. caninum was associated with 41% of fetuses submitted compared to 13.3% during passive surveillance (P<0.001). Breed of dam was significantly associated with N. caninum diagnosis, with a higher prevalence in dairy versus beef breeds, and fetuses of 3–6 months gestational age had the highest prevalence of N. caninum. There was no significant association with dam parity. Neospora caninum was diagnosed in every year except 2009 and cases were geographically widespread throughout the province. Furthermore, the active surveillance program demonstrates that N. caninum is highly prevalent in the Upper Fraser Valley and is a major causal agent of production losses in this dairy intensive region. PMID:26872927

  2. A review of neosporosis and pathologic findings of Neospora caninum infection in wildlife.

    Science.gov (United States)

    Donahoe, Shannon L; Lindsay, Scott A; Krockenberger, Mark; Phalen, David; Šlapeta, Jan

    2015-08-01

    Neospora caninum is an apicomplexan parasite that is the etiologic agent of neosporosis, a devastating infectious disease regarded as a major cause of reproductive loss in cattle and neuromuscular disease in dogs worldwide. This protozoan pathogen is maintained in the environment by a heteroxenous life cycle that involves a definitive canid host and a wide range of intermediate hosts. In recent years, a number of wildlife species have been investigated for their possible involvement in the N. caninum life cycle and many have been implicated as intermediate hosts. However, in many instances these studies have utilized serological and molecular techniques to detect infection in clinically normal animals, and investigation of possible associated morbidity, mortality, and pathology has been neglected. As such, the occurrence and importance of Neospora-associated disease in wildlife species are unknown. In order to improve our understanding of the significance of N. caninum infection in nondomestic species, the present review provides an up-to-date summary of clinical neosporosis and N. caninum-associated pathologic lesions in naturally and experimentally infected wildlife species. We provide a list of all free-ranging and captive wildlife species identified with N. caninum infection to date using currently available diagnostic tools. The advantages and disadvantages of diagnostic methods in wildlife are addressed in order to recommend optimal diagnosis of confirming N. caninum infection and neosporosis in nondomestic species. Although current data would suggest that N. caninum infection does not adversely impact wildlife populations, there is a need for greater international uniformity in the diagnosis of N. caninum infection and neosporosis in nondomestic species in order to assess the true consequences of parasite infection.

  3. Neospora caninum calcium-dependent protein kinase 1 is an effective drug target for neosporosis therapy.

    Science.gov (United States)

    Ojo, Kayode K; Reid, Molly C; Kallur Siddaramaiah, Latha; Müller, Joachim; Winzer, Pablo; Zhang, Zhongsheng; Keyloun, Katelyn R; Vidadala, Rama Subba Rao; Merritt, Ethan A; Hol, Wim G J; Maly, Dustin J; Fan, Erkang; Van Voorhis, Wesley C; Hemphill, Andrew

    2014-01-01

    Despite the enormous economic importance of Neospora caninum related veterinary diseases, the number of effective therapeutic agents is relatively small. Development of new therapeutic strategies to combat the economic impact of neosporosis remains an important scientific endeavor. This study demonstrates molecular, structural and phenotypic evidence that N. caninum calcium-dependent protein kinase 1 (NcCDPK1) is a promising molecular target for neosporosis drug development. Recombinant NcCDPK1 was expressed, purified and screened against a select group of bumped kinase inhibitors (BKIs) previously shown to have low IC50s against Toxoplasma gondii CDPK1 and T. gondii tachyzoites. NcCDPK1 was inhibited by low concentrations of BKIs. The three-dimensional structure of NcCDPK1 in complex with BKIs was studied crystallographically. The BKI-NcCDPK1 structures demonstrated the structural basis for potency and selectivity. Calcium-dependent conformational changes in solution as characterized by small-angle X-ray scattering are consistent with previous structures in low Calcium-state but different in the Calcium-bound active state than predicted by X-ray crystallography. BKIs effectively inhibited N. caninum tachyzoite proliferation in vitro. Electron microscopic analysis of N. caninum cells revealed ultra-structural changes in the presence of BKI compound 1294. BKI compound 1294 interfered with an early step in Neospora tachyzoite host cell invasion and egress. Prolonged incubation in the presence of 1294 interfered produced observable interference with viability and replication. Oral dosing of BKI compound 1294 at 50 mg/kg for 5 days in established murine neosporosis resulted in a 10-fold reduced cerebral parasite burden compared to untreated control. Further experiments are needed to determine the PK, optimal dosage, and duration for effective treatment in cattle and dogs, but these data demonstrate proof-of-concept for BKIs, and 1294 specifically, for therapy of bovine

  4. Filarial worms reduce Plasmodium infectivity in mosquitoes.

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    Matthew T Aliota

    2011-02-01

    Full Text Available Co-occurrence of malaria and filarial worm parasites has been reported, but little is known about the interaction between filarial worm and malaria parasites with the same Anopheles vector. Herein, we present data evaluating the interaction between Wuchereria bancrofti and Anopheles punctulatus in Papua New Guinea (PNG. Our field studies in PNG demonstrated that An. punctulatus utilizes the melanization immune response as a natural mechanism of filarial worm resistance against invading W. bancrofti microfilariae. We then conducted laboratory studies utilizing the mosquitoes Armigeres subalbatus and Aedes aegypti and the parasites Brugia malayi, Brugia pahangi, Dirofilaria immitis, and Plasmodium gallinaceum to evaluate the hypothesis that immune activation and/or development by filarial worms negatively impact Plasmodium development in co-infected mosquitoes. Ar. subalbatus used in this study are natural vectors of P. gallinaceum and B. pahangi and they are naturally refractory to B. malayi (melanization-based refractoriness.Mosquitoes were dissected and Plasmodium development was analyzed six days after blood feeding on either P. gallinaceum alone or after taking a bloodmeal containing both P. gallinaceum and B. malayi or a bloodmeal containing both P. gallinaceum and B. pahangi. There was a significant reduction in the prevalence and mean intensity of Plasmodium infections in two species of mosquito that had dual infections as compared to those mosquitoes that were infected with Plasmodium alone, and was independent of whether the mosquito had a melanization immune response to the filarial worm or not. However, there was no reduction in Plasmodium development when filarial worms were present in the bloodmeal (D. immitis but midgut penetration was absent, suggesting that factors associated with penetration of the midgut by filarial worms likely are responsible for the observed reduction in malaria parasite infections.These results could have an

  5. Seroprevalence of antibody to NcSAG1 antigen of Neospora caninum in cattle from Western Java, Indonesia.

    Science.gov (United States)

    Ichikawa-Seki, Madoka; Guswanto, Azirwan; Allamanda, Puttik; Mariamah, Euis Siti; Wibowo, Putut Eko; Nishikawa, Yoshifumi

    2016-01-01

    Neospora caninum can cause fetal abortion and neonatal mortality in cattle, and is a cause of economic concern worldwide. This study aimed to determine the prevalence of Neospora caninum-specific antibodies in cattle from Western Java, Indonesia. Serum samples from 991 cattle from 21 locations were tested for antibodies to N. caninum by using an enzyme-linked immunosorbent assay (ELISA) on the basis of recombinant NcSAG1. The overall seroprevalence was 16.6%, ranging from 0 to 87.5% in the sampled locations. The results of this study indicate latent infection rates of sampled animals were different in each location. Further studies are necessary to elucidate the relationship between N. caninum infection and abortion in cattle, and to identify risk factors for infection in high-prevalence environments.

  6. Diagnosis and treatment of Neospora caninum--associated dermatitis in a red fox (Vulpes vulpes) with concurrent Toxoplasma gondii infection.

    Science.gov (United States)

    Duhey, Jitender P; Whitesell, Leah E; Culp, William E; Daye, Sharon

    2014-06-01

    A 3-mo-old red fox (Vulpes vulpes) developed generalized crusty plaques on its body during rehabilitation after an automobile accident requiring amputation of one leg. Histologic examination of skin lesion biopsy revealed granulomatous dermatitits with many intralesional protozoal tachyzoites. The protozoa stained positively with antibodies to Neospora caninum but not to Toxoplasma gondii. Treatment with clindamycin hydrochloride (10 mg/kg, twice daily, s.c.) for 1 mo completely resolved lesions, and protozoa were not demonstrable in biopsy of skin after treatment. The fox had agglutinating antibodies to T. gondii (modified agglutination test, titer 1:3200) and N. caninum (Neospora agglutination test, titer 1:25), and viable T. gondii (genotype III) was isolated from the skin biopsy after treatment. This is the first report of clinical neosporosis in a wild canid.

  7. Towards a preventive strategy for neosporosis: challenges and future perspectives for vaccine development against infection with Neospora caninum.

    Science.gov (United States)

    Nishikawa, Yoshifumi

    2017-08-10

    Neosporosis is caused by the intracellular protozoan parasite Neospora caninum. This major disease-causing pathogen is responsible for inducing abortion in cattle, and these adverse events occur sporadically all over the world, including Japan. Currently, there are no vaccines on the market against infection with N. caninum. Because live and attenuated vaccines against N. caninum have had safety and effectiveness issues, development of a next-generation vaccine is urgently required. To develop a vaccine against neosporosis, my laboratory has been focused on the following: 1) understanding the host immune responses against Neospora infection, 2) identifying vaccine antigens and 3) developing an effective antigen-delivery system. The research strategy taken in my laboratory will have strong potential to progress current understanding of the pathogenesis of N. caninum infection and promote development of a novel subunit vaccine based on the specific vaccine antigen with an antigen-delivery system for controlling neosporosis.

  8. Mosquito immune defenses against Plasmodium infection.

    Science.gov (United States)

    Cirimotich, Chris M; Dong, Yuemei; Garver, Lindsey S; Sim, Shuzhen; Dimopoulos, George

    2010-04-01

    The causative agent of malaria, Plasmodium, has to undergo complex developmental transitions and survive attacks from the mosquito's innate immune system to achieve transmission from one host to another through the vector. Here we discuss recent findings on the role of the mosquito's innate immune signaling pathways in preventing infection by the Plasmodium parasite, the identification and mechanistic description of novel anti-parasite molecules, the role that natural bacteria harbored in the mosquito midgut might play in this immune defense and the crucial parasite and vector molecules that mediate midgut infection.

  9. Cyclic nucleotide specific phosphodiesterases of Leishmania major

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    Linder Markus

    2006-03-01

    Full Text Available Abstract Background Leishmania represent a complex of important human pathogens that belong to the systematic order of the kinetoplastida. They are transmitted between their human and mammalian hosts by different bloodsucking sandfly vectors. In their hosts, the Leishmania undergo several differentiation steps, and their coordination and optimization crucially depend on numerous interactions between the parasites and the physiological environment presented by the fly and human hosts. Little is still known about the signalling networks involved in these functions. In an attempt to better understand the role of cyclic nucleotide signalling in Leishmania differentiation and host-parasite interaction, we here present an initial study on the cyclic nucleotide-specific phosphodiesterases of Leishmania major. Results This paper presents the identification of three class I cyclic-nucleotide-specific phosphodiesterases (PDEs from L. major, PDEs whose catalytic domains exhibit considerable sequence conservation with, among other, all eleven human PDE families. In contrast to other protozoa such as Dictyostelium, or fungi such as Saccharomyces cerevisiae, Candida ssp or Neurospora, no genes for class II PDEs were found in the Leishmania genomes. LmjPDEA contains a class I catalytic domain at the C-terminus of the polypeptide, with no other discernible functional domains elsewhere. LmjPDEB1 and LmjPDEB2 are coded for by closely related, tandemly linked genes on chromosome 15. Both PDEs contain two GAF domains in their N-terminal region, and their almost identical catalytic domains are located at the C-terminus of the polypeptide. LmjPDEA, LmjPDEB1 and LmjPDEB2 were further characterized by functional complementation in a PDE-deficient S. cerevisiae strain. All three enzymes conferred complementation, demonstrating that all three can hydrolyze cAMP. Recombinant LmjPDEB1 and LmjPDEB2 were shown to be cAMP-specific, with Km values in the low micromolar range

  10. Occurrence of antibodies anti-Neospora spp. in cart horses and Crioula breed horses from Rio Grande do Sul state

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    G Toscan

    2011-02-01

    Full Text Available O objetivo deste estudo foi avaliar a frequência de detecção de anticorpos contra Neospora spp. em cavalos de carroça e em cavalos da raça Crioula. Para tal, 214 amostras de soro foram coletadas e analisadas pela técnica de imunofluorescência indireta, das quais 91 eram de cavalos de carroça e 123 de cavalos da raça Crioula, todas provenientes da região central do Rio Grande do Sul. As frequências de anticorpos detectadas foram: 15,9% (34/214 na população total estudada, 15,4% (14/91 nos cavalos de carroça e 16,3% (20/123 nos cavalos da raça Crioula. Estes resultados sugerem que a infecção por Neospora spp. está presente igualmente nas duas populaç ões. Assim, devido à importância e ao padrão da patogênese da neosporose em equinos, Neospora spp. deve ser incluído no diagnóstico de problemas reprodutivos em éguas e em casos de problemas neurológicos em equinos.

  11. Fecal and Molecular Survey of Neospora caninum in Farm and Household Dogs in Mashhad Area, Khorasan Province, Iran

    Science.gov (United States)

    2009-01-01

    Neospora caninum is an important cause of abortion in dairy cattle worldwide. Dog is the definitive host for N. caninum and can infect dairy cattle. The aim of this study is to determine the prevalence of Neospora oocysts in feces of dogs from dairy farms. A total of 174 fecal samples was collected from 89 farm dogs and 85 household dogs during 2006 and 2008. Fecal samples of dogs were microscopically examined for detecting Hammondia Neospora-like oocysts (HNLO) by Mini Parasep®SF fecal parasite concentrator. HNLO were microscopically detected in 4 fecal samples (2.2%). The fecal samples with HNLO were examined by N. caninum-specific PCR. Two of the samples were positive for N. caninum. The 2 positive fecal samples were selected for inoculation to calves. Two inoculated calves were seronegative by ELISA for 4 months post-infection. This is the first report of finding N. caninum DNA in feces of farm dogs in Mashhad area, Iran. PMID:19967094

  12. Phenotypic characterisation of the cellular immune infiltrate in placentas of cattle following experimental inoculation with Neospora caninum in late gestation

    Science.gov (United States)

    2013-01-01

    Despite Neospora caninum being a major cause of bovine abortion worldwide, its pathogenesis is not completely understood. Neospora infection stimulates host cell-mediated immune responses, which may be responsible for the placental damage leading to abortion. The aim of the current study was to characterize the placental immune response following an experimental inoculation of pregnant cattle with N. caninum tachyzoites at day 210 of gestation. Cows were culled at 14, 28, 42 and 56 days post inoculation (dpi). Placentomes were examined by immunohistochemistry using antibodies against macrophages, T-cell subsets (CD4, CD8 and γδ), NK cells and B cells. Macrophages were detected mainly at 14 days post inoculation. Inflammation was generally mild and mainly characterized by CD3+, CD4+ and γδ T-cells; whereas CD8+ and NK cells were less numerous. The immune cell repertoire observed in this study was similar to those seen in pregnant cattle challenged with N. caninum at early gestation. However, cellular infiltrates were less severe than those seen during first trimester Neospora infections. This may explain the milder clinical outcome observed when animals are infected late in gestation. PMID:23876124

  13. Neospora caninum--how close are we to development of an efficacious vaccine that prevents abortion in cattle?

    Science.gov (United States)

    Reichel, Michael P; Ellis, John T

    2009-09-01

    Neospora caninum is a protozoan parasite that causes abortion in cattle around the world. Although the clinical signs of disease in both dogs and cattle have now been recognised for over 20years, treatment and control options are still limited, despite the availability of a commercial vaccine in some countries of the world. The case for an efficacious vaccine has not been convincingly waged by farmers, veterinarians and other members of the agricultural and rural communities. In recent times, however, economic modelling has been used to estimate the industry losses due to Neospora-associated abortion, providing, in turn, the business case for forms of control for this parasite, including the development of vaccines. In this review, we document progress in all areas of the vaccine development pipeline, including live, killed and recombinant forms and the animal models available for vaccine evaluation. In addition, we summarise the main outcomes on the economics of Neospora control and suggest that the current boom in the global dairy industry increases the specific need for a vaccine against N. caninum-associated abortion.

  14. An epidemic outbreak of canine cutaneous leishmaniasis in Colombia caused by Leishmania braziliensis and Leishmania panamensis.

    Science.gov (United States)

    Vélez, Iván D; Carrillo, Lina M; López, Liliana; Rodríguez, Erwin; Robledo, Sara M

    2012-05-01

    The largest recorded outbreak of cutaneous leishmaniasis in Colombia's history occurred during 2005-2009 in soldiers of the Colombian Army, with ~40,000 cases. This outbreak was caused by the influx of military personnel into the jungle with the mission of combat illicit crops and the guerrilla. The soldiers remain for long periods within the rainforest and are exposed to the bite of infected sand flies. During the military activities, soldiers work with dogs specially trained to detect landmines, and therefore, dogs are also exposed to the infected sand flies and show high incidence of cutaneous leishmaniasis (CL). This work describes an epidemic outbreak of canine CL caused by Leishmania braziliensis and Leishmania panamensis in Colombia, South America. The clinical features of the disease and the response to treatment with pentavalent antimonials observed in 72 guard dogs from the Colombian Army are described. A program for prevention and control of canine CL is also discussed.

  15. Antiproliferative and ultrastructural effects of phenethylamine derivatives on promastigotes and amastigotes of Leishmania (Leishmania) infantum chagasi.

    Science.gov (United States)

    Brasil, Paula Ferreira; de Freitas, Júlia Araújo; Barreto, Anna Léa Silva; Adade, Camila Marques; Reis de Sá, Leandro Figueira; Constantino-Teles, Pamella; Toledo, Fabiano Travanca; de Sousa, Bruno A; Gonçalves, Augusto Cesar; Romanos, Maria Teresa Villela; Comasseto, João V; Dos Santos, Alcindo A; Tessis, Ana Claudia; Souto-Padrón, Thais; Soares, Rosangela Maria A; Ferreira-Pereira, Antonio

    2017-04-01

    Leishmania (Leishmania) infantum chagasi is one of the agents that cause visceral leishmaniasis. This disease occurs more frequently in third world countries, such as Brazil. The treatment is arduous, and is dependent on just a few drugs like the antimonial derivatives and amphotericin B. Moreover, these drugs are not only expensive, but they can also cause severe side effects and require long-term treatment. Therefore, it is very important to find new compounds that are effective against leishmaniasis. In the present work we evaluated a new group of synthetic amides against the promastigote and amastigote forms of L. infantum chagasi. The results showed that one of these amides in particular, presented very effective activity against the promastigotes and amastigotes of L. infantum chagasi at low concentrations and it also presented low toxicity for mammal cells, which makes this synthetic amide a promising drug for combating leishmaniasis. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.

  16. Vector Competence of Lutzomyia cruzi Naturally Demonstrated for Leishmania infantum and Suspected for Leishmania amazonensis.

    Science.gov (United States)

    de Oliveira, Everton Falcão; Oshiro, Elisa Teruya; Fernandes, Wagner Souza; Ferreira, Alda Maria Teixeira; de Oliveira, Alessandra Gutierrez; Galati, Eunice Aparecida Bianchi

    2017-01-11

    Corumbá city is one of the oldest visceral leishmaniasis-endemic foci in the state of Mato Grosso do Sul, Brazil, where the transmission of Leishmania infantum has been attributed to Lutzomyia cruzi Aiming at investigating the parameters of the vectorial capacity of Lu. cruzi for L. infantum, a project was undertaken in this city. Among these parameters, vector competence was investigated and the results obtained are reported herein. Of the 12 hamsters exposed to feed wild-caught female sandflies, two developed infection with L. infantum and surprisingly, one with Leishmania amazonensis In addition, hamsters with L. infantum infection were bitten only by females of Lu. cruzi, whereas the hamster infected with L. amazonensis was bitten by 124 Lu. cruzi females and one of Evandromyia corumbaensis Although there is a strong suspicion regarding the competence of Lu. cruzi in transmitting L. amazonensis naturally, it was not demonstrated. © The American Society of Tropical Medicine and Hygiene.

  17. Mucosal Leishmaniasis caused by Leishmania (Viannia braziliensis and Leishmania (Viannia guyanensis in the Brazilian Amazon.

    Directory of Open Access Journals (Sweden)

    Jorge Augusto de Oliveira Guerra

    Full Text Available BACKGROUND: Leishmania (Viannia braziliensis is a parasite recognized as the most important etiologic agent of mucosal leishmaniasis (ML in the New World. In Amazonia, seven different species of Leishmania, etiologic agents of human Cutaneous Leishmaniasis, have been described. Isolated cases of ML have been described for several different species of Leishmania: L. (V. panamensis, L. (V. guyanensis and L. (L. amazonensis. METHODOLOGY: Leishmania species were characterized by polymerase chain reaction (PCR of tissues taken from mucosal biopsies of Amazonian patients who were diagnosed with ML and treated at the Tropical Medicine Foundation of Amazonas (FMTAM in Manaus, Amazonas state, Brazil. Samples were obtained retrospectively from the pathology laboratory and prospectively from patients attending the aforementioned tertiary care unit. RESULTS: This study reports 46 cases of ML along with their geographical origin, 30 cases caused by L. (V. braziliensis and 16 cases by L. (V. guyanensis. This is the first record of ML cases in 16 different municipalities in the state of Amazonas and of simultaneous detection of both species in 4 municipalities of this state. It is also the first record of ML caused by L. (V. guyanensis in the states of Pará, Acre, and Rondônia and cases of ML caused by L. (V. braziliensis in the state of Rondônia. CONCLUSIONS/SIGNIFICANCE: L. (V. braziliensis is the predominant species that causes ML in the Amazon region. However, contrary to previous studies, L. (V. guyanensis is also a significant causative agent of ML within the region. The clinical and epidemiological expression of ML in the Manaus region is similar to the rest of the country, although the majority of ML cases are found south of the Amazon River.

  18. Promoter regions of Plasmodium vivax are poorly or not recognized by Plasmodium falciparum

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    del Portillo Hernando A

    2007-02-01

    Full Text Available Abstract Background Heterologous promoter analysis in Plasmodium has revealed the existence of conserved cis regulatory elements as promoters from different species can drive expression of reporter genes in heterologous transfection assays. Here, the functional characterization of different Plasmodium vivax promoters in Plasmodium falciparum using luciferase as the reporter gene is presented. Methods Luciferase reporter plasmids harboring the upstream regions of the msp1, dhfr, and vir3 genes as well as the full-length intergenic regions of the vir23/24 and ef-1α genes of P. vivax were constructed and transiently transfected in P. falciparum. Results Only the constructs with the full-length intergenic regions of the vir23/24 and ef-1α genes were recognized by the P. falciparum transcription machinery albeit to values approximately two orders of magnitude lower than those reported by luc plasmids harbouring promoter regions from P. falciparum and Plasmodium berghei. A bioinformatics approach allowed the identification of a motif (GCATAT in the ef-1α intergenic region that is conserved in five Plasmodium species but is degenerate (GCANAN in P. vivax. Mutations of this motif in the P. berghei ef-1α promoter region decreased reporter expression indicating it is active in gene expression in Plasmodium. Conclusion Together, this data indicates that promoter regions of P. vivax are poorly or not recognized by the P. falciparum transcription machinery suggesting the existence of P. vivax-specific transcription regulatory elements.

  19. Implications of a Neotropical Origin of the Genus Leishmania

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    Noyes Harry

    1998-01-01

    Full Text Available The hypothesis of a Neotropical origin of the Leishmania/Endotrypanum clade is reviewed. The position of the L. (Sauroleishmania external to the subgenus L. (Leishmania is not consistent with the Neotropical origin of the latter subgenus. It is suggested that this may be a consequence of a faster evolutionary rate in the L. (Sauroleishmania. The implications for the classsification of the phlebotomine sandflies of the hypothesis for a Neotropical origin of the Leishmania is also considered. The classification of Galati (1995 is proposed to be most consistent with the hypothesis of a Neotropical origin of the Leishmania, whilst classifications which place the New and Old World species in separate taxa are inconsistent with this hypothesis.

  20. Leishmania RNA virus controls the severity of mucocutaneous leishmaniasis.

    Science.gov (United States)

    Ives, Annette; Ronet, Catherine; Prevel, Florence; Ruzzante, Giulia; Fuertes-Marraco, Silvia; Schutz, Frederic; Zangger, Haroun; Revaz-Breton, Melanie; Lye, Lon-Fye; Hickerson, Suzanne M; Beverley, Stephen M; Acha-Orbea, Hans; Launois, Pascal; Fasel, Nicolas; Masina, Slavica

    2011-02-11

    Mucocutaneous leishmaniasis is caused by infections with intracellular parasites of the Leishmania Viannia subgenus, including Leishmania guyanensis. The pathology develops after parasite dissemination to nasopharyngeal tissues, where destructive metastatic lesions form with chronic inflammation. Currently, the mechanisms involved in lesion development are poorly understood. Here we show that metastasizing parasites have a high Leishmania RNA virus-1 (LRV1) burden that is recognized by the host Toll-like receptor 3 (TLR3) to induce proinflammatory cytokines and chemokines. Paradoxically, these TLR3-mediated immune responses rendered mice more susceptible to infection, and the animals developed an increased footpad swelling and parasitemia. Thus, LRV1 in the metastasizing parasites subverted the host immune response to Leishmania and promoted parasite persistence.

  1. Cutaneous leishmaniasis with lymphadenopathy due to Leishmania donovani

    NARCIS (Netherlands)

    Faber, W. R.; Wonders, J.; Jensema, A. J.; Chocholova, E.; Kager, P. A.

    2009-01-01

    Summary We describe a case of cutaneous leishmaniasis with lymphadenopathy due to Leishmania donovani, which was successfully treated with oral miltefosine. Given the increased prevalence of travelling, patients presenting with lymph-node enlargement should have leishmaniasis included in the

  2. Novel Leishmania and Malaria Potassium Channels: Candidate Therapeutic Targets

    National Research Council Canada - National Science Library

    McDonald, Thomas V

    2005-01-01

    .... major and T. cruzi). Using a combination of cultured mammalian cells and Xenopus oocytes for heterologous expression we have evidence that 2 channels from malaria [PFK1 & PFK22] and Leishmania [LMK1 & LMK2] generate K+...

  3. Efficacy of Recombinant Canine Distemper Virus Expressing Leishmania Antigen against Leishmania Challenge in Dogs.

    Directory of Open Access Journals (Sweden)

    Ryuichi Miura

    Full Text Available Canine distemper virus (CDV vaccination confers long-term protection against CDV reinfection. To investigate the utility of CDV as a polyvalent vaccine vector for Leishmania, we generated recombinant CDVs, based on an avirulent Yanaka strain, that expressed Leishmania antigens: LACK, TSA, or LmSTI1 (rCDV-LACK, rCDV-TSA, and rCDV-LmSTI1, respectively. Dogs immunized with rCDV-LACK were protected against challenge with lethal doses of virulent CDV, in the same way as the parental Yanaka strain. To evaluate the protective effects of the recombinant CDVs against cutaneous leishmaniasis in dogs, dogs were immunized with one recombinant CDV or a cocktail of three recombinant CDVs, before intradermal challenge (in the ears with infective-stage promastigotes of Leishmania major. Unvaccinated dogs showed increased nodules with ulcer formation after 3 weeks, whereas dogs immunized with rCDV-LACK showed markedly smaller nodules without ulceration. Although the rCDV-TSA- and rCDV-LmSTI1-immunized dogs showed little protection against L. major, the cocktail of three recombinant CDVs more effectively suppressed the progression of nodule formation than immunization with rCDV-LACK alone. These results indicate that recombinant CDV is suitable for use as a polyvalent live attenuated vaccine for protection against both CDV and L. major infections in dogs.

  4. Natural canine infection by Leishmania infantum and Leishmania amazonensis and their implications for disease control

    Directory of Open Access Journals (Sweden)

    Letícia da Cruz Sanches

    Full Text Available Abstract Leishmaniasis is a major public health problem worldwide. Because Leishmania can adapt to new hosts or vectors, knowledge concerning the current etiological agent in dogs is important in endemic areas. This study aimed to identify the Leishmania species detected in 103 samples of peripheral blood from dogs that were naturally infected with these protozoa. The diagnosis of leishmaniasis was determined through parasitological examination, the indirect enzyme-linked immunosorbent assay (ELISA and the polymerase chain reaction (PCR. The Leishmania species were identified by means of PCR-restriction fragment length polymorphism (PCR-RFLP. The samples were subjected to PCR using oligonucleotide primers that amplify the intergenic region ITS1 of the rRNA gene in order to identify the species. The amplified DNA was digested using the restriction enzyme HaeIII. A restriction profile identical to L. amazonensis was shown in 77/103 samples and the profile was similar to L. infantum in 17/103. However, a mixed profile was shown in 9/103 samples, which impeded species identification. In conclusion, the infection in these dogs was predominantly due to L. amazonensis, thus indicating that diagnosing of cases of canine leishmaniasis needs to be reexamined, since the causative agent identified is not restricted to L. infantum.

  5. A comparison of molecular markers to detect Lutzomyia longipalpis naturally infected with Leishmania (Leishmania infantum

    Directory of Open Access Journals (Sweden)

    Kárita Cláudia Freitas-Lidani

    2014-07-01

    Full Text Available The aim of the present study was to detect natural infection by Leishmania (Leishmania infantum in Lutzomyia longipalpis captured in Barcarena, state of Pará, Brazil, through the use of three primer sets. With this approach, it is unnecessary to previously dissect the sandfly specimens. DNA of 280 Lu. longipalpis female specimens were extracted from the whole insects. PCR primers for kinetoplast minicircle DNA (kDNA, the mini-exon gene and the small subunit ribosomal RNA (SSU-rRNA gene of Leishmania were used, generating fragments of 400 bp, 780 bp and 603 bp, respectively. Infection by the parasite was found with the kDNA primer in 8.6% of the cases, with the mini-exon gene primer in 7.1% of the cases and with the SSU-rRNA gene primer in 5.3% of the cases. These data show the importance of polymerase chain reaction as a tool for investigating the molecular epidemiology of visceral leishmaniasis by estimating the risk of disease transmission in endemic areas, with the kDNA primer representing the most reliable marker for the parasite.

  6. Efficacy of Recombinant Canine Distemper Virus Expressing Leishmania Antigen against Leishmania Challenge in Dogs.

    Science.gov (United States)

    Miura, Ryuichi; Kooriyama, Takanori; Yoneda, Misako; Takenaka, Akiko; Doki, Miho; Goto, Yasuyuki; Sanjoba, Chizu; Endo, Yasuyuki; Fujiyuki, Tomoko; Sugai, Akihiro; Tsukiyama-Kohara, Kyoko; Matsumoto, Yoshitsugu; Sato, Hiroki; Kai, Chieko

    2015-01-01

    Canine distemper virus (CDV) vaccination confers long-term protection against CDV reinfection. To investigate the utility of CDV as a polyvalent vaccine vector for Leishmania, we generated recombinant CDVs, based on an avirulent Yanaka strain, that expressed Leishmania antigens: LACK, TSA, or LmSTI1 (rCDV-LACK, rCDV-TSA, and rCDV-LmSTI1, respectively). Dogs immunized with rCDV-LACK were protected against challenge with lethal doses of virulent CDV, in the same way as the parental Yanaka strain. To evaluate the protective effects of the recombinant CDVs against cutaneous leishmaniasis in dogs, dogs were immunized with one recombinant CDV or a cocktail of three recombinant CDVs, before intradermal challenge (in the ears) with infective-stage promastigotes of Leishmania major. Unvaccinated dogs showed increased nodules with ulcer formation after 3 weeks, whereas dogs immunized with rCDV-LACK showed markedly smaller nodules without ulceration. Although the rCDV-TSA- and rCDV-LmSTI1-immunized dogs showed little protection against L. major, the cocktail of three recombinant CDVs more effectively suppressed the progression of nodule formation than immunization with rCDV-LACK alone. These results indicate that recombinant CDV is suitable for use as a polyvalent live attenuated vaccine for protection against both CDV and L. major infections in dogs.

  7. Plasmodium falciparum malaria and antimalarial interventions in ...

    African Journals Online (AJOL)

    Plasmodium falciparum malaria is one of the most important parasitic diseases affecting sub-Saharan Africa, despite the availability of interventions. It exerts tremendous socio-economic and medical burden on the continent, particularly in under five children and pregnant women. In this review, we have attempted to ...

  8. Resistance patterns of plasmodium falciparum malaria to ...

    African Journals Online (AJOL)

    Resistance patterns of plasmodium falciparum malaria to chloroquine in Kampala, Uganda. ... Sixty three (65.6%) patients showed clinical improvement, 29 (30.2%) deteriorated and four (4.2%) had no change. Adequate parasitogical response was seen in 71 (74 %), moderate in four (4.2%) and poor in 21 (21.8%) patients.

  9. Immunoglobulin profile of Nigerian children with Plasmodium ...

    African Journals Online (AJOL)

    SERVER

    2008-01-18

    Jan 18, 2008 ... Dodoo D, Theander TG, Kurtzhals JAL, Koram K, Riley E, Akanmori. BD, Nkruma FK, Hviid L (1999). Levels of Antibody to conserve parts of Plasmodium falciparum merozoite surface protein 1 in Ghanaian children are not associated with protection from clinical malaria. Infect. Immun. 67(5): 2131-2137.

  10. Plasmodium-induced inflammation by uric acid.

    Directory of Open Access Journals (Sweden)

    Jamie M Orengo

    2008-03-01

    Full Text Available Infection of erythrocytes with the Plasmodium parasite causes the pathologies associated with malaria, which result in at least one million deaths annually. The rupture of infected erythrocytes triggers an inflammatory response, which is induced by parasite-derived factors that still are not fully characterized. Induced secretion of inflammatory cytokines by these factors is considered a major cause of malaria pathogenesis. In particular, the inflammatory cytokine tumor necrosis factor (TNF is thought to mediate most of the life-threatening pathologies of the disease. Here we describe the molecular characterization of a novel pathway that results in the secretion of TNF by host cells. We found that erythrocytes infected by Plasmodium accumulate high concentrations of hypoxanthine and xanthine. Degradation of Plasmodium-derived hypoxanthine/xanthine results in the formation of uric acid, which triggers the secretion of TNF. Since uric acid is considered a "danger signal" released by dying cells to alert the immune system, Plasmodium appears to have co-evolved to exploit this warning system. Identifying the mechanisms used by the parasite to induce the host inflammatory response is essential to develop urgently needed therapies against this disease.

  11. SHORT COMMUNICATION High prevalence of Plasmodium ...

    African Journals Online (AJOL)

    Dell

    Abstract. Malaria and Human Immunodeficiency Virus (HIV) infections are major public health problems in Sub-Saharan. Africa. Their overlapping geographical distribution and co-existence often result into high morbidity and mortality. This study was designed to establish the prevalence of Plasmodium falciparum malaria ...

  12. Limitations of microscopy to differentiate Plasmodium species in a region co-endemic for Plasmodium falciparum, Plasmodium vivax and Plasmodium knowlesi

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    Barber Bridget E

    2013-01-01

    Full Text Available Abstract Background In areas co-endemic for multiple Plasmodium species, correct diagnosis is crucial for appropriate treatment and surveillance. Species misidentification by microscopy has been reported in areas co-endemic for vivax and falciparum malaria, and may be more frequent in regions where Plasmodium knowlesi also commonly occurs. Methods This prospective study in Sabah, Malaysia, evaluated the accuracy of routine district and referral hospital-based microscopy, and microscopy performed by an experienced research microscopist, for the diagnosis of PCR-confirmed Plasmodium falciparum, P. knowlesi, and Plasmodium vivax malaria. Results A total of 304 patients with PCR-confirmed Plasmodium infection were enrolled, including 130 with P. knowlesi, 122 with P. falciparum, 43 with P. vivax, one with Plasmodium malariae and eight with mixed species infections. Among patients with P. knowlesi mono-infection, routine and cross-check microscopy both identified 94 (72% patients as “P. malariae/P. knowlesi”; 17 (13% and 28 (22% respectively were identified as P. falciparum, and 13 (10% and two (1.5% as P. vivax. Among patients with PCR-confirmed P. falciparum, routine and cross-check microscopy identified 110/122 (90% and 112/118 (95% patients respectively as P. falciparum, and 8/122 (6.6% and 5/118 (4.2% as “P. malariae/P. knowlesi”. Among those with P. vivax, 23/43 (53% and 34/40 (85% were correctly diagnosed by routine and cross-check microscopy respectively, while 13/43 (30% and 3/40 (7.5% patients were diagnosed as “P. malariae/P. knowlesi”. Four of 13 patients with PCR-confirmed P. vivax and misdiagnosed by routine microscopy as “P. malariae/P. knowlesi” were subsequently re-admitted with P. vivax malaria. Conclusions Microscopy does not reliably distinguish between P. falciparum, P. vivax and P. knowlesi in a region where all three species frequently occur. Misdiagnosis of P. knowlesi as both P. vivax and P. falciparum, and

  13. Plasmodium knowlesi in travellers, update 2014.

    Science.gov (United States)

    Müller, Mattia; Schlagenhauf, Patricia

    2014-05-01

    Since the initial discovery of Plasmodium knowlesi in Malaysia, cases have been reported from several neighbouring countries. Tourism has also resulted in an increasing number of cases diagnosed in Europe, America, and Oceania. In this review we focus on the risk of the travel-associated acquisition of P. knowlesi malaria. A search of the literature in PubMed was carried out to identify articles and literature on the distribution of P. knowlesi infections in Southeast Asia and details of its acquisition and importation by travellers to other continents. The cut-off date for the search was December 1, 2013. Search words used were: "Plasmodium knowlesi", "Plasmodium knowlesi infections", "Plasmodium knowlesi travellers", "Plasmodium knowlesi prevalence", "Plasmodium knowlesi host", "Plasmodium knowlesi vector" "Plasmodium knowlesi RDT", and "Plasmodium knowlesi Malaysia". Traveller numbers to Malaysia were obtained from the Tourism Malaysia website. A total of 103 articles were found. Using a selection of these and others identified from the reference lists of the papers, we based our review on a total of 66 articles. P. knowlesi malaria appears to be the most common malaria species in Malaysian Borneo and is also widely distributed on the Malaysian mainland. Furthermore, locally transmitted cases of P. knowlesi malaria have been reported in Thailand, the Philippines, Vietnam, Singapore, Myanmar, Indonesian Borneo, and Cambodia. Two cases have been reported from non-endemic countries in Asia (Japan and Taiwan) in people with a history of travel to Malaysia and the Philippines. Twelve cases were imported to their home countries by travellers from other continents: two from the USA, two from the Netherlands, two from Germany, and one each from Spain, France, Sweden, Finland, Australia, and New Zealand. In most cases, the infection was associated with a trip to or near forested areas. The symptoms were fever (n=12), headache (n=6), chills (n=6), nausea (n=4), myalgia (n

  14. Sequencing and Gene Expression Analysis of Leishmania tropica LACK Gene.

    Science.gov (United States)

    Hammoudeh, Nour; Kweider, Mahmoud; Abbady, Abdul-Qader; Soukkarieh, Chadi

    2014-01-01

    Leishmania Homologue of receptors for Activated C Kinase (LACK) antigen is a 36-kDa protein, which provokes a very early immune response against Leishmania infection. There are several reports on the expression of LACK through different life-cycle stages of genus Leishmania, but only a few of them have focused on L.tropica. The present study provides details of the cloning, DNA sequencing and gene expression of LACK in this parasite species. First, several local isolates of Leishmania parasites were typed in our laboratory using PCR technique to verify of Leishmania parasite species. After that, LACK gene was amplified and cloned into a vector for sequencing. Finally, the expression of this molecule in logarithmic and stationary growth phase promastigotes, as well as in amastigotes, was evaluated by Reverse Transcription-PCR (RT-PCR) technique. The typing result confirmed that all our local isolates belong to L.tropica. LACK gene sequence was determined and high similarity was observed with the sequences of other Leishmania species. Furthermore, the expression of LACK gene in both promastigotes and amastigotes forms was confirmed. Overall, the data set the stage for future studies of the properties and immune role of LACK gene products.

  15. immune response in human leishmania infections Respuesta inmune en infecciones humanas por Leishmania spp

    Directory of Open Access Journals (Sweden)

    Sara María Robledo Restrepo

    2000-03-01

    Full Text Available This review summarizes relevant information about the immune response triggered during leishmaniosis, a disease of great importance from the epidemiological point of view, since it is endemic in Colombia and other countries. We emphasize on human leishmaniosis; nevertheless, some important findings in the murine model are also mentioned. This information allows to conclude that Leishmania infection is a complex and coordinated process, which includes adhesion and entrance of the parasite into the host cells and its survival inside them. Events that mediate the infection process may influence its result in terms of elimination of the parasite or development of the disease, through induction or not of an effective specific immune response which involves host cell activation and parasite destruction. La presente revisión tiene como objetivo resumir la información más relevante acerca de la respuesta inmune que se desencadena durante la leishmaniosis, una enfermedad de gran importancia desde el punto de vista epidemiológico dado que es endémica en Colombia y otros países. Aunque la respuesta inmune en la leishmaniosis es un tema que se ha estudiado ampliamente en las infecciones por especies de Leishmania del Viejo Mundo, particularmente Leishmania major y Leishmania donovani y en el modelo murino, la presente revisión hace énfasis en la leishmaniosis humana. Algunos hallazgos importantes en el modelo murino también se mencionan. La información contenida en la revisión, en su mayoría, proviene de publicaciones derivadas de investigaciones, las cuales se seleccionaron con base en la calidad del trabajo realizado y en los aportes de sus resultados en el avance del conocimiento sobre las infecciones en humanos. La síntesis de la información seleccionada nos permite concluir que la infección por Leishmania es un proceso complejo y coordinado que incluye la adherencia y entrada del parásito a la célula hospedera y su posterior

  16. Asymptomatic dogs are highly competent to transmit Leishmania (Leishmania) infantum chagasi to the natural vector.

    Science.gov (United States)

    Laurenti, Márcia Dalastra; Rossi, Claudio Nazaretian; da Matta, Vânia Lúcia Ribeiro; Tomokane, Thaise Yumie; Corbett, Carlos Eduardo Pereira; Secundino, Nágila Francinete Costa; Pimenta, Paulo Filemon Paulocci; Marcondes, Mary

    2013-09-23

    We evaluated the ability of dogs naturally infected with Leishmania (Leishmania) infantum chagasi to transfer the parasite to the vector and the factors associated with transmission. Thirty-eight infected dogs were confirmed to be infected by direct observation of Leishmania in lymph node smears. Dogs were grouped according to external clinical signs and laboratory data into symptomatic (n=24) and asymptomatic (n=14) animals. All dogs were sedated and submitted to xenodiagnosis with F1-laboratory-reared Lutzomyia longipalpis. After blood digestion, sand flies were dissected and examined for the presence of promastigotes. Following canine euthanasia, fragments of skin, lymph nodes, and spleen were collected and processed using immunohistochemistry to evaluate tissue parasitism. Specific antibodies were detected using an enzyme-linked immunosorbent assay. Antibody levels were found to be higher in symptomatic dogs compared to asymptomatic dogs (p=0.0396). Both groups presented amastigotes in lymph nodes, while skin parasitism was observed in only 58.3% of symptomatic and in 35.7% of asymptomatic dogs. Parasites were visualized in the spleens of 66.7% and 71.4% of symptomatic and asymptomatic dogs, respectively. Parasite load varied from mild to intense, and was not significantly different between groups. All asymptomatic dogs except for one (93%) were competent to transmit Leishmania to the vector, including eight (61.5%) without skin parasitism. Sixteen symptomatic animals (67%) infected sand flies; six (37.5%) showed no amastigotes in the skin. Skin parasitism was not crucial for the ability to infect Lutzomyia longipalpis but the presence of Leishmania in lymph nodes was significantly related to a positive xenodiagnosis. Additionally, a higher proportion of infected vectors that fed on asymptomatic dogs was observed (p=0.0494). Clinical severity was inversely correlated with the infection rate of sand flies (p=0.027) and was directly correlated with antibody

  17. Delayed culture of Leishmania in skin biopsies.

    Science.gov (United States)

    Dedet, J P; Pratlong, F; Pradinaud, R; Moreau, B

    1999-01-01

    Between January 1997 and October 1998, 16 skin biopsies collected from 13 patients with cutaneous leishmaniasis in French Guiana were inoculated in culture medium after travel for 3-17 days from the place of biopsy to the culture laboratory in France. Each biopsy fragment was introduced near the flame of a Bunsen burner into the transport medium (RPMI medium supplemented with 10% fetal calf serum) which was maintained at ambient temperature during postal delivery to France. In France the biopsies were ground in sterile saline before being inoculated into NNN culture tubes. The cultures were incubated at 25 degrees C and subcultured every week until the 5th week. The cultures were positive in 9 cases, remained negative in 4, and were contaminated in 3 cases. Positive results were obtained at all seasons and for 3 different Leishmania species. The study indicates that delayed culture can yield useful results from biopsies taken in field conditions.

  18. Occurrence of anti-Neospora caninum and anti-Toxoplasma gondii antibodies in horses in the Pantanal of Mato Grosso, Brazil

    Directory of Open Access Journals (Sweden)

    Luciane Maria Laskoski

    2015-04-01

    Full Text Available This study aimed to evaluate the occurrence of anti-Neospora caninum and anti-Toxoplasma gondii antibodies in horses from Pantanal, in Mato Grosso state. Two hundred blood samples were collected from horses in Pantanal of Mato Grosso, Brazil. The samples were analyzed by IFAT for the detection of anti-Neospora caninum and anti-Toxoplasma gondii antibodies. Antibodies to N. caninum were found in 30 (15% of 200 horses in titers of 50 (25 horses, 100 (two horses, 200 (two horses, and 400 (one horse. Antibodies to T. gondii were found in five (2.5% of 200 horses in titers of 50 (three horses, 200 (one horse, and 400 (one horse. One animal showed antibody titers for both coccidian (titers of 200 for N. caninum e 400 for T. gondii. The pantaneiros horses were exposed to Neospora spp. and T. gondii.

  19. Molecular Identification of Leishmania spp. in Sand Flies (Diptera: Psychodidae, Phlebotominae) From Ecuador

    Science.gov (United States)

    Cevallos, Varsovia; Morales, Diego; Baldeón, Manuel E; Cárdenas, Paúl; Rojas-Silva, Patricio; Ponce, Patricio

    2017-01-01

    Abstract The detection and identification of natural infections in sand flies by Leishmania protozoan species in endemic areas is a key factor in assessing the risk of leishmaniasis and in designing prevention and control measures for this infectious disease. In this study, we analyzed the Leishmania DNA using nuclear ribosomal internal transcript spacer (ITS) sequences. Parasite DNA was extracted from naturally infected, blood-fed sand flies collected in nine localities considered leishmaniasis-endemic foci in Ecuador. The species of parasites identified in sand flies were Leishmania major-like, Leishmania naiffi, Leishmania mexicana, Leishmania lainsoni, and “Leishmania sp. siamensis”. Sand fly specimens of Brumptomyia leopoldoi, Mycropigomyia cayennensis, Nyssomyia yuilli yuilli, Nyssomyia trapidoi, Pressatia triacantha, Pressatia dysponeta, Psychodopygus carrerai carrerai, Psychodopygus panamensis, and Trichophoromyia ubiquitalis were found positive for Leishmania parasite. These findings contribute to a better understanding of the epidemiology and transmission dynamics of the disease in high-risk areas of Ecuador. PMID:28981860

  20. Case Report: First Case of Cutaneous Leishmaniasis Caused by Leishmania (Viannia) braziliensis in Suriname

    NARCIS (Netherlands)

    Hu, Ricardo V. P. F.; Kent, Alida D.; Adams, Emily R.; van der Veer, Charlotte; Sabajo, Leslie O. A.; Mans, Dennis R. A.; de Vries, Henry J. C.; Schallig, Henk D. F. H.; Fat, Rudy F. M. Lai A.

    2012-01-01

    The main causative agent of cutaneous leishmaniasis (CL) in Suriname is Leishmania (Viannia) guyanensis. This case report presents a patient infected with Leishmania (Viannia) braziliensis, a species never reported before in Suriname. This finding has clinical implications, because L. braziliensis

  1. Cell mediated immune responses in the placenta following challenge of vaccinated pregnant heifers with Neospora caninum.

    Science.gov (United States)

    Hecker, Y P; Cantón, G; Regidor-Cerrillo, J; Chianini, F; Morrell, E; Lischinsky, L; Ortega-Mora, L M; Innes, E A; Odeón, A; Campero, C M; Moore, D P

    2015-12-15

    The aim of the present study was to investigate and correlate the cell-mediated immune response and pathological changes at the maternal-fetal interface of Neospora-challenged pregnant cattle previously immunized with live and inactivated experimental vaccines. Pregnant heifers naïve to Neospora caninum were divided in 5 groups of 4 animals, each one immunized before mating: Group A heifers were intravenously (iv) immunized with 6.25 × 10(7) live tachyzoites of the NC-6 strain; group B heifers were immunized twice subcutaneously (sc) 3 weeks apart with native antigen extract of the NC-6 strain formulated with ISCOMs; group C heifers were sc immunized twice 3 weeks apart with three recombinant proteins (rNcSAG1, rNcHSP20, rNcGRA7) of the NC-1 strain formulated with ISCOMs; group D heifers were sc injected with sterile phosphate-buffered saline (PBS) and group E heifers received sc ISCOM-matrix (ISCOMs without antigen). All groups were iv-challenged with 4.7 × 10(7) NC-1 tachyzoites at 70 days of gestation. Heifers were culled at day 104 of gestation and placentomes were examined to evaluate lesions and local cellular immune responses using histopathology, immunohistochemistry and real time-PCR. Immunohistochemistry was performed using bovine leucocyte specific antibodies. Cytokine expression and levels (IFN-γ, IL-4, IL-10, IL-12 and TNF-α) were measured using real-time reverse transcription-PCR and ELISA, respectively. Minimal inflammation was observed in group A placentomes; while placentomes from group B, C, D and E had moderate to severe infiltration with CD3(+), CD4(+), γδ-T cells, CD8(+) cells and macrophages being more numerous in groups B and E placentomes, when compared with groups C and D (P<0.001). Cytokine levels were significantly increased in the caruncles of animals of groups B and C in comparison with the other animal groups (P < 0.001). The results from this study showed that the strongest cellular immune responses were observed in the

  2. Toxoplasma gondii, Neospora caninum, Sarcocystis neurona, and Sarcocystis canis-like infections in marine mammals

    Science.gov (United States)

    Dubey, J.P.; Zarnke, R.; Thomas, N.J.; Wong, S.K.; Vanbonn, W.; Briggs, M.; Davis, J.W.; Ewing, R.; Mense, M.; Kwok, O.C.H.; Romand, S.; Thulliez, P.

    2003-01-01

    Toxoplasma gondii, Neospora caninum, Sarcocystis neurona, and S. canis are related protozoans that can cause mortality in many species of domestic and wild animals. Recently, T. gondii and S. neurona were recognized to cause encephalitis in marine mammals. As yet, there is no report of natural exposure of N. caninum in marine mammals. In the present study, antibodies to T. gondii and N. caninum were assayed in sera of several species of marine mammals. For T. gondii, sera were diluted 1:25, 1:50, and 1:500 and assayed in the T. gondii modified agglutination test (MAT). Antibodies (MAT a?Y1:25) to T. gondii were found in 89 of 115 (77%) dead, and 18 of 30 (60%) apparently healthy sea otters (Enhydra lutris), 51 of 311 (16%) Pacific harbor seals (Phoca vitulina), 19 of 45 (42%) sea lions (Zalophus californianus), 5 of 32 (16%) ringed seals (Phoca hispida), 4 of 8 (50%) bearded seals (Erignathus barbatus), 1 of 9 (11.1%) spotted seals (Phoca largha), 138 of 141 (98%) Atlantic bottlenose dolphins (Tursiops truncatus), and 3 of 53 (6%) walruses (Odobenus rosmarus). For N. caninum, sera were diluted 1:40, 1:80, 1:160, and 1:320 and examined with the Neospora agglutination test (NAT) using mouse-derived tachyzoites. NAT antibodies were found in 3 of 53 (6%) walruses, 28 of 145 (19%) sea otters, 11 of 311 (3.5%) harbor seals, 1 of 27 (3.7%) sea lions, 4 of 32 (12.5%) ringed seals, 1 of 8 (12.5%) bearded seals, and 43 of 47 (91%) bottlenose dolphins. To our knowledge, this is the first report of N. caninum antibodies in any marine mammal, and the first report of T. gondii antibodies in walruses and in ringed, bearded, spotted, and ribbon seals. Current information on T. gondii-like and Sarcocystis-like infections in marine mammals is reviewed. New cases of clinical S. canis and T. gondii infections are also reported in sea lions, and T. gondii infection in an Antillean manatee (Trichechus manatus manatus).

  3. Bifurcation in the chemotactic behavior of Physarum plasmodium

    Science.gov (United States)

    Shirakawa, Tomohiro; Gunji, Yukio-Pegio; Sato, Hiroshi; Tsubakino, Hiroto

    2017-07-01

    The plasmodium of true slime mold Physarum polycephalum is a unicellular and multinuclear giant amoeba. Since the cellular organism has some computational abilities, it is attracting much attention in the field of information science. However, previous studies have mainly focused on the optimization behavior of the plasmodium for a single-modality stimulus, and there are few studies on how the organism adapts to multi-modal stimuli. We stimulated the plasmodium with mixture of attractant and repellent stimuli, and we observed bifurcation in the chemotactic behavior of the plasmodium.

  4. Highly Dynamic Host Actin Reorganization around Developing Plasmodium Inside Hepatocytes

    Science.gov (United States)

    Gomes-Santos, Carina S. S.; Itoe, Maurice A.; Afonso, Cristina; Henriques, Ricardo; Gardner, Rui; Sepúlveda, Nuno; Simões, Pedro D.; Raquel, Helena; Almeida, António Paulo; Moita, Luis F.; Frischknecht, Friedrich; Mota, Maria M.

    2012-01-01

    Plasmodium sporozoites are transmitted by Anopheles mosquitoes and infect hepatocytes, where a single sporozoite replicates into thousands of merozoites inside a parasitophorous vacuole. The nature of the Plasmodium-host cell interface, as well as the interactions occurring between these two organisms, remains largely unknown. Here we show that highly dynamic hepatocyte actin reorganization events occur around developing Plasmodium berghei parasites inside human hepatoma cells. Actin reorganization is most prominent between 10 to 16 hours post infection and depends on the actin severing and capping protein, gelsolin. Live cell imaging studies also suggest that the hepatocyte cytoskeleton may contribute to parasite elimination during Plasmodium development in the liver. PMID:22238609

  5. Identification of geographically distributed sub-populations of Leishmania (Leishmania major by microsatellite analysis

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    Schwenkenbecher Jan

    2008-06-01

    Full Text Available Abstract Background Leishmania (Leishmania major, one of the agents causing cutaneous leishmaniasis (CL in humans, is widely distributed in the Old World where different species of wild rodent and phlebotomine sand fly serve as animal reservoir hosts and vectors, respectively. Despite this, strains of L. (L. major isolated from many different sources over many years have proved to be relatively uniform. To investigate the population structure of the species highly polymorphic microsatellite markers were employed for greater discrimination among it's otherwise closely related strains, an approach applied successfully to other species of Leishmania. Results Multilocus Microsatellite Typing (MLMT based on 10 different microsatellite markers was applied to 106 strains of L. (L. major from different regions where it is endemic. On applying a Bayesian model-based approach, three main populations were identified, corresponding to three separate geographical regions: Central Asia (CA; the Middle East (ME; and Africa (AF. This was congruent with phylogenetic reconstructions based on genetic distances. Re-analysis separated each of the populations into two sub-populations. The two African sub-populations did not correlate well with strains' geographical origin. Strains falling into the sub-populations CA and ME did mostly group according to their place of isolation although some anomalies were seen, probably, owing to human migration. Conclusion The model- and distance-based analyses of the microsatellite data exposed three main populations of L. (L. major, Central Asia, the Middle East and Africa, each of which separated into two sub-populations. This probably correlates with the different species of rodent host.

  6. Neutrophils reduce the parasite burden in Leishmania (Leishmania amazonensis-infected macrophages.

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    Erico Vinícius de Souza Carmo

    2010-11-01

    Full Text Available Studies on the role of neutrophils in Leishmania infection were mainly performed with L. (L major, whereas less information is available for L. (L amazonensis. Previous results from our laboratory showed a large infiltrate of neutrophils in the site of infection in a mouse strain resistant to L. (L. amazonensis (C3H/HePas. In contrast, the susceptible strain (BALB/c displayed a predominance of macrophages harboring a high number of amastigotes and very few neutrophils. These findings led us to investigate the interaction of inflammatory neutrophils with L. (L. amazonensis-infected macrophages in vitro.Mouse peritoneal macrophages infected with L. (L. amazonensis were co-cultured with inflammatory neutrophils, and after four days, the infection was quantified microscopically. Data are representative of three experiments with similar results. The main findings were 1 intracellular parasites were efficiently destroyed in the co-cultures; 2 the leishmanicidal effect was similar when cells were obtained from mouse strains resistant (C3H/HePas or susceptible (BALB/c to L. (L. amazonensis; 3 parasite destruction did not require contact between infected macrophages and neutrophils; 4 tumor necrosis factor alpha (TNF-α, neutrophil elastase and platelet activating factor (PAF were involved with the leishmanicidal activity, and 5 destruction of the parasites did not depend on generation of oxygen or nitrogen radicals, indicating that parasite clearance did not involve the classical pathway of macrophage activation by TNF-α, as reported for other Leishmania species.The present results provide evidence that neutrophils in concert with macrophages play a previously unrecognized leishmanicidal effect on L. (L. amazonensis. We believe these findings may help to understand the mechanisms involved in innate immunity in cutaneous infection by this Leishmania species.

  7. Engineered anopheles immunity to Plasmodium infection.

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    Yuemei Dong

    2011-12-01

    Full Text Available A causative agent of human malaria, Plasmodium falciparum, is transmitted by Anopheles mosquitoes. The malaria parasite is under intensive attack from the mosquito's innate immune system during its sporogonic development. We have used genetic engineering to create immune-enhanced Anopheles stephensi mosquitoes through blood meal-inducible expression of a transgene encoding the IMD pathway-controlled NF-kB Rel2 transcription factor in the midgut and fat-body tissue. Transgenic mosquitoes showed greater resistance to Plasmodium and microbial infection as a result of timely concerted tissue-specific immune attacks involving multiple effectors. The relatively weak impact of this genetic modification on mosquito fitness under laboratory conditions encourages further investigation of this approach for malaria control.

  8. The sub-genera of Avian Plasmodium

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    Landau I.

    2010-03-01

    Full Text Available The study of the morphology of a species of Plasmodium is difficult because these organisms have relatively few characters. The size of the schizont, for example, which is easy to assess is important at the specific level but is not always of great phylogenetic significance. Factors reflecting the parasite’s metabolism provide more important evidence. Thus the position of the parasite within the host red cell (attachment to the host nucleus or its membrane, at one end or aligned with it has been shown to be constant for a given species. Another structure of essential significance that is often ignored is a globule, usually refringent in nature, that was first described in Plasmodium vaughani Novy & MacNeal, 1904 and that we consider to be characteristic of the sub-genus Novyella. Species without this structure, previously classified in this sub-genus, are now included in the new sub-genus Papernaia n. sg.

  9. Plasmodium knowlesi malaria in Vietnam: some clarifications

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    Hung Le

    2010-01-01

    Full Text Available Abstract A recently published comment on a report of Plasmodium knowlesi infections in Vietnam states that this may not accurately represent the situation in the study area because the PCR primers used may cross-hybridize with Plasmodium vivax. Nevertheless, P. knowlesi infections have been confirmed by sequencing. In addition, a neighbour-joining tree based on the 18S S-Type SSUrRNA gene shows that the Vietnamese samples clearly cluster with the P. knowlesi isolates identified in Malaysia and are distinct from the corresponding P. vivax sequences. All samples came from asymptomatic individuals who did not consult for fever during the months preceding or following the survey, indicating that asymptomatic P. knowlesi infections occur in this population, although this does not exclude the occurrence of symptomatic cases. Large-scale studies to determine the extent and the epidemiology of P. knowlesi malaria in Vietnam are further needed.

  10. Peptone-yeast autolysate-fetal bovine serum 10, a simple, inexpensive liquid medium for cultivation of Leishmania spp.

    OpenAIRE

    Palomino, J C

    1982-01-01

    A simple liquid medium for the cultivation of Leishmania parasites is described. Leishmania brasiliensis and Leishmania peruviana cultured in this medium reached cell densities greater than 10(7) promastigotes per ml within 7 days. This medium compares very favorably with the more complex media used to cultivate Leishmania spp. and other hemoflagellates.

  11. Immunoglobulin profile of Nigerian children with Plasmodium ...

    African Journals Online (AJOL)

    The immunoglobulin profiles of 126 Nigerian children infected with Plasmodium falciparum in their peripheral blood were investigated. The mean malarial parasitaemia was 4699.17 ± 3695.2 ìl. The mean immunoglobulin profile of these infected children were 2.68 ± 0.019 mg/dl for IgA, 0.031 ± 0.01 mg/dl for IgD, 1358.29 ...

  12. An alternative method for Plasmodium culture synchronization.

    Science.gov (United States)

    Lelièvre, J; Berry, A; Benoit-Vical, F

    2005-03-01

    Since the synchronization of Plasmodium falciparum has become an essential tool in research, we have investigated the use of a commercial gelatine solution, Plasmion, to replace Plasmagel, which is now difficult to obtain. This method also avoids the use of techniques based on Percoll-glucose gradients. The Plasmion-based technique proved to be a good method and could become an alternative to Plasmagel.

  13. Hyposplenism revealed by Plasmodium malariae infection

    OpenAIRE

    Hommel, Benjamin; Galloula, Alexandre; Simon, Anne; Buffet, Pierre

    2013-01-01

    International audience; BACKGROUND: Hyposplenism, due to splenectomy, inherited red blood cell disorders or acquired conditions such as celiac disease, has an important impact on the severity of malaria, especially in non-immune patients. Conversely, that malaria may reveal functional hyposplenism has not been described previously. METHODS: A 31-year old gardener was diagnosed with an uncomplicated attack of Plasmodium malariae 11 years after leaving the endemic area. In addition to trophozoi...

  14. Embryonated pigeon eggs as a model to investigate Neospora caninum infection.

    Science.gov (United States)

    Bahrami, Somayeh; Rezaie, Annahita; Boroomand, Zahra; Namavari, Mehdi; Ghavami, Sepideh

    2017-04-01

    It has been shown that embryonated chicken eggs can be used as animal models for experimental infections. The aim of the present study was to investigate pigeon embryonated eggs as animal models for experimental neosporosis. An infection with Neospora caninum Nc1 isolate was conducted in chicken and pigeon embryonated eggs to evaluate LD50. After calculation of LD50, 2LD50 of tachyzoites were injected into the eggs. Macroscopic changes of each embryo were observed, and immunohistochemistry (IHC) and molecular methods were used to investigate the parasitic distribution in the tissues. In the present study, histopathological changes were considered, and sections of those used for histopathological examination including the heart, liver, brain and chorioallantoic (CA) membrane were also subjected to IHC. Pigeon embryos showed more macroscopic changes than chicken embryos. A hemorrhage of the CA membrane was the main gross lesion. Microscopic examination of tissues revealed acute neosporosis due to hemorrhage, necrosis and infiltration of mononuclear inflammatory cells. Based on IHC and molecular results, the parasite DNA was detected in the liver, heart and CA membrane. As with chicken embryonated eggs, these results reinforce the susceptibility of pigeon embryonated eggs to N. caninum, and provide new insights into using an inexpensive and available animal model for N. caninum research. The results of the present study suggest that pigeon embryos may be a good choice for studying the biology of N. caninum in living organisms.

  15. Assessment of transplacental transmission of Neospora caninum in dairy cattle in the Agreste region of Pernambuco.

    Science.gov (United States)

    Ramos, Inalda Angélica de Souza; Silva, Rafael José da; Maciel, Thiago Arcoverde; Afonso da Silva, José Augusto Bastos; Fidelis, Otavio Luiz; Soares, Pierre Castro; Machado, Rosangela Zacarias; André, Marcos Rogério; Mendonça, Carla Lopes de

    2016-01-01

    The transplacental transmission is the primary route of Neospora caninum infection in bovine herds around the world. This study aimed to determine the frequency of transplacental transmission of the parasite in dairy cattle of Agreste region of Pernambuco through serological tests (IFAT and ELISA). Three hundred sixteen serum samples from cows and heifers and their offspring were analyzed. The transplacental transmission rate was 72.22% (13/18) for cows and 69.23% (9/13) for heifers by IFAT. ELISA test showed transplacental transmission rate of 43.58% (17/39) for cows and 50% (9/18) for heifers. The transplacental transmission rates were similar, in both groups in test, but a higher seropositivity was found in cows by IFAT. Data were statistically analyzed using the chi-square and Fisher's exact test. A significant relationship of dependence between seropositivity of mothers and their offspring was found. The more frequent IFAT antibody titers and ELISA levels for N. caninum were, respectively, 200 and between four (cows) and five (heifers and offspring). In the Spearman correlation, no association was found between the magnitude of antibody titers for N. caninum between mothers and their offspring. The kappa test showed an index of 0.35, indicating a mild correlation between the serological tests used. The study suggests that cows and heifers are the main transmitters of N. caninum in the studied region and that vertical transmission is the major form of transmission in dairy herds of the Agreste region of Pernambuco.

  16. Neospora caninum and Toxoplasma gondii antibodies in red foxes (Vulpes vulpes) in the Czech Republic.

    Science.gov (United States)

    Bártová, Eva; Slezáková, Radka; Nágl, Ivan; Sedlák, Kamil

    2016-01-01

    Neospora caninum and Toxoplasma gondii are worldwide spread parasites, causing serious illnesses in sensitive animals; toxoplasmosis is also important zoonosis. Although neosporosis is not considered as a zoonosis, it leads to aborted births in cattle, as well as paresis and paralysis in dogs. The aim of this study was to discover the prevalence of N. caninum and T. gondii antibodies in red foxes (Vulpes vulpes) in the Czech Republic. Sera of 80 foxes from 8 regions of the Czech Republic were tested for antibodies to N. caninum and T. gondii by competitive enzyme linked immunosorbent assay (cELISA) and indirect ELISA. All samples were simultaneously tested by indirect fluorescent antibody test (IFAT) to detect both N. caninum and T. gondii antibodies. Antibodies to N. caninum were found by IFAT in 3 (3.8%) red foxes with titre 50 and in 2 (2.5%) red foxes with inhibition 42.7% and 30.2 %. Antibodies to T. gondii were found in all tested animals in both IFAT (titres 50-6400) and in ELISA (S/P ranging from 34%-133%). This is the first prevalence study of N. caninum and T. gondii antibodies in red foxes in the Czech Republic. The results obtained show that red foxes are exposed at different levels to both protozoan infections, and thus could play an important role in the transmission cycle of N. caninum and T. gondii in sylvatic cycle.

  17. Neospora caninum versus Brucella spp. exposure among dairy cattle in Ethiopia: a case control study.

    Science.gov (United States)

    Asmare, Kassahun

    2014-08-01

    This case-control study aimed at assessing the relative association of Neospora caninum and Brucella species exposure with reproductive disorders. The study was carried out between October 2011 and June 2012 on 731 dairy cows sampled from 150 dairy farms in selected 17 conurbations of Ethiopia. Two hundred sixty-six of the cows were categorized as cases based on their history of abortion or stillbirth while the remaining 465 were controls. The presence of antibody to N. caninum was screened using indirect ELISA, while Brucella spp. exposure was assayed serially using Rose Bengal Plate Test and Complement Fixation Test. Exposure to N. caninum was more frequently observed among cases (23.8%) than controls (12.7%), while no significant difference (p > 0.05) was noted for Brucella exposure between the two groups. Moreover, the proportion of cows with disorders like retention of fetal membrane, endometritis and increased inter-calving period were significantly higher (p Brucella spp. exposure. However, neither N. caninum nor Brucella spp. could explain the majority (73.2%) of the reported abortions and stillbirths in cattle. Hence, this observation underscores the need for more intensive investigation on the identification of causes of the aforementioned disorders in dairy cattle of Ethiopia.

  18. Flavonoids Modulate the Proliferation of Neospora caninum in Glial Cell Primary Cultures

    Science.gov (United States)

    Barbosa de Matos, Rosan; Braga-de-Souza, Suzana; Pena Seara Pitanga, Bruno; Amaral da Silva, Victor Diógenes; Viana de Jesus, Erica Etelvina; Morales Pinheiro, Alexandre; Dias Costa, Maria de Fátima; dos Santos El-Bacha, Ramon; de Oliveira Ribeiro, Cátia Suse

    2014-01-01

    Neospora caninum (Apicomplexa; Sarcocystidae) is a protozoan that causes abortion in cattle, horses, sheep, and dogs as well as neurological and dermatological diseases in dogs. In the central nervous system of dogs infected with N. caninum, cysts were detected that exhibited gliosis and meningitis. Flavonoids are polyphenolic compounds that exhibit antibacterial, antiparasitic, antifungal, and antiviral properties. In this study, we investigated the effects of flavonoids in a well-established in vitro model of N. caninum infection in glial cell cultures. Glial cells were treated individually with 10 different flavonoids, and a subset of cultures was also infected with the NC-1 strain of N. caninum. All of the flavonoids tested induced an increase in the metabolism of glial cells and many of them increased nitrite levels in cultures infected with NC-1 compared to controls and uninfected cultures. Among the flavonoids tested, 3',4'-dihydroxyflavone, 3',4',5,7-tetrahydroxyflavone (luteolin), and 3,3',4',5,6-pentahydroxyflavone (quercetin), also inhibited parasitophorous vacuole formation. Taken together, our findings show that flavonoids modulate glial cell responses, increase NO secretion, and interfere with N. caninum infection and proliferation. PMID:25548412

  19. Concomitant infection of Neospora caninum and Bovine Herpesvirus type 5 in spontaneous bovine abortions

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    Maia S. Marin

    2013-11-01

    Full Text Available Bovine Herpesvirus type 5 (BoHV-5 has not been conclusively demonstrated to cause bovine abortion. Brain lesions produced by Neospora caninum and Bovine Herpesvirus type 1 (BoHV-1 exhibit common features. Therefore, careful microscopic evaluation and additional diagnostic procedures are required to achieve an accurate final etiological diagnosis. The aim of the present work was to investigate the occurrence of infections due to BoHV-1, BoHV-5 and N. caninum in 68 cases of spontaneous bovine abortions which showed microscopic lesions in the fetal central nervous system. This study allowed the identification of 4 (5.9% fetuses with dual infection by BoHV-5 and N. caninum and 33 (48.5% cases in which N. caninum was the sole pathogen identified. All cases were negative to BoHV-1. The results of this study provide evidence that dual infection by BoHV-5 and N. caninum occur during pregnancy in cattle; however, the role of BoHV-5 as a primary cause of bovine abortion needs further research. Molecular diagnosis of BoHV-5 and N. caninum confirmed the importance of applying complementary assays to improve the sensitivity of diagnosing bovine abortion.

  20. Seroprevalence of Neospora caninum in dairy cattle from north-west and centre of Romania

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    Gavrea R.R.

    2011-11-01

    Full Text Available Neosporosis is a disease that mainly affects cattle in both dairy and beef herds. The main definitive host of this parasite is the dog. Since 1984 and its first description a large number of data were published worldwide on this parasite. In Romania, the research regarding this parasite is limited. The purpose of this study was to determine the seroprevalence of Neospora caninum infection in dairy cattle from six regions in north-western Romania and to evaluate the intensity of infection in different animals groups. A total number of 901 samples (862 sera from adult cows and 39 sera from calves were collected from dairy farms and were screened for the presence of specific IgG anti-bodies using an enzyme-linked immunosorbent assay (ELISA. The overall seroprevalence for neosporosis was 34.6%. In adult cows and calves seroprevalences reached 34.8% (300/862 and 30.8% for calves (12/39 respectively. In cattle which had previously aborted, seroprevalence was 40.9%. These results indicate that N. caninum infection is widespread among animals reared in dairy systems from Romania and a program for farmer training and a strategy for reducing the economic impact of the disease are needed.

  1. Serological study of Neospora caninum infection in dogs in central China.

    Science.gov (United States)

    Wang, Shuai; Yao, Zhijun; Zhang, Nian; Wang, Dong; Ma, Jingbo; Liu, Shiguo; Zheng, Bin; Zhang, Bin; Liu, Kuo; Zhang, Haizhu

    2016-01-01

    Neospora caninum is a protozoan parasite that causes abortion in cattle as well as reproduction problems and neurological disorders in dogs. Dogs are important in the epidemiology of N. caninum because they act as definitive hosts, shedding oocysts in the environment. To investigate the seroprevalence of N. caninum infection in dogs in central China, 1176 serum samples were collected from domestic dogs in Henan province, central China between March 2015 and February 2016 and tested for IgG antibody against N. caninum, using the indirect fluorescent antibody test (IFAT). The overall seroprevalence of N. caninum was nearly 15% (172/1176). No significant difference was observed between this seroprevalence according to sex and breed of dogs (p > 0.05). The infection rate in rural dogs (18%) was higher (p dogs (11%). The prevalence of N. caninum infection in dogs increased (p dogs in Henan province, central China. Sanitary conditions and animal health must be improved to prevent the transmission risk of N. caninum by dogs. © S. Wang et al., published by EDP Sciences, 2016.

  2. Seroprevalence and risk factors for Neospora caninum in small dairy farms in central Chile

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    Luis Hervé-Claude1

    2017-01-01

    Full Text Available Objective. To provide information about seroprevalence and risk factors of Neospora caninum infection in bovines of central Chile. Material and Methods. The study population are small dairy farms that are part of a Government Technical Support Service (SAT in the O´Higgins region in central Chile. Sera samples were collected from milking cows and analyzed by a commercial ELISA kit. Additionally, a questionnaire was applied to farmers to identify risk factors through logistic regression. Results. The farm level prevalence was found to be 67%, and within farms seroprevalence 55%. Abortion history (p= 0.037, OR=5.09, dogs feed source (p= 0.0429, OR=6, cattle drinking water source (p=0.034, OR=4.5 and abortions management (p=0.017, OR=7.43 were found as significant risk factors for infection. Conclusion. There is a high N. caninum seroprevalence in small SAT´s dairy farms in O´Higgins region. These results highlight the need of improving N. caninum surveillance, and the development of preventive measures to avoid losses related with this disease.

  3. A Long-Term Study of Neospora caninum Infection in a Swedish Dairy Herd

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    Uggla Arvid

    2003-06-01

    Full Text Available A longitudinal study was performed in a Swedish dairy herd where Neospora caninum had been isolated from a stillborn calf. Starting in autumn 1994, blood samples from all female animals in the herd were collected once yearly until 1999. The sera were analysed for presence of IgG1 antibodies to N. caninum by the iscom ELISA, and by an avidity ELISA to establish the timing of infection. In addition, data on reproductive performance were compiled. During the study the percentage of seropositive female animals increased from 63% to 87%. In 1994 a large number of young animals tested seropositive although their dams were seronegative, indicating that a transmission of the parasite other than the vertical had recently occurred. Low avidity values supported this assumption. The annual abortion rate increased from a mean of 2% before the initiation of the study to 9% in 1994–1998. During the same time, as judged by the avidity data, a large proportion of the animals shifted from being recently to being chronically infected. The source of the external infection in the herd could not be identified.

  4. Serological survey of Neospora caninum in dairy herds from Parauapebas, State of Pará

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    Clovis Laurindo Silva

    2015-02-01

    Full Text Available Neospora caninum is a coccidian protozoan that affects cattle worldwide causing economic losses. To survey the frequency of anti-N. caninum antibodies in dairy herds in the municipality of Parauapebas, Southeast of Pará, samples of 465 sera from 45 farms were subjected to indirect immunofluorescence assay (cutoff 1:100. Anti-N. caninum antibodies were found with a frequency of 13,33% with the following titer distribution: 27 (43,55% for titer 100; 14 (22,58% for 200; 16 (25,80% for 400, and 5 (8,07% for 800; no serum titers more than 800 was noted, but at least one positive animal was present in most farms. The highest frequency occurred among females, with no significant difference in frequency between the sexes (Fisher exact test = 0,59, P = 0,99; 2-year-old animals had the highest frequency, although their numbers were lesser than those aged >5 years, with no significant difference in frequency between the age groups (?2 = 2,1, P = 0,71. No significant difference was observed between the frequency and occurrence of abortion (?2 = 2,3, P = 0,13 and frequency and presence of dogs in the farms (?2 = 0,26, P = 0,60. Actions toward health monitoring are recommended to prevent the entry of new sources of N. caninum and to control its spread within herds.

  5. Seroepidemiological survey of Neospora caninum and its risk factors in farm dogs in Nakuru district, Kenya

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    Tequiero Abuom Okumu

    2016-10-01

    Full Text Available Aim: The objective of this study was to determine the seroprevalence of Neospora caninum (NC and its risk factors in farm dogs in Kenya. Materials and Methods: As part of a longitudinal study on dairy cattle abortion in 2010 in Kenya, serum samples were collected from 84 dogs in 53 randomly selected dairy cattle farms to determine the seroprevalence and risk factors of seropositivity for NC. Results: 15 (17.9% of the dogs were seropositive to NC antibodies, and at least one seropositive dog was found in 12 (22.6% of the 53 farms. The final multivariable logistic regression model identified free-roaming as the only factor significantly associated with seropositivity (odds ratio=4.48; p=0.03. Conclusion: The findings of this study indicate that canine neosporosis does exist in Kenya and that farmers should restrict their dogs from roaming to reduce the risk of their dogs becoming a reservoir for NC. More studies need to be carried out to determine the reproductive effects of NC on dairy cattle in Kenya.

  6. Activation of a Neospora caninum EGFR-Like Kinase Facilitates Intracellular Parasite Proliferation

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    Xiaoxia Jin

    2017-10-01

    Full Text Available The Apicomplexan parasite Neospora caninum, an obligate intracellular protozoan, causes serious diseases in a number of mammalian species, especially in cattle. Infection with N. caninum is associated with abortions in both dairy and beef cattle worldwide which have a major economic impact on the cattle industry. However, the mechanism by which N. caninum proliferates within host cells is poorly understood. Epidermal growth factor receptor (EGFR is a protein kinase ubiquitously expressed, present on cell surfaces in numerous species, which has been confirmed to be essential in signal transduction involved in cell growth, proliferation, survival, and many other intracellular processes. However, the presence of EGFR in N. caninum and its role in N. caninum proliferation remain unclear. In the present study, we identified a putative EGFR-like kinase in N. caninum, which could be activated in tachyzoites by infection or treatment with rNcMIC3 [containing four epidermal growth factor (EGF domains] or human EGF. Blockade of EGFR-like in tachyzoites by AG1478 significantly reduced parasite proliferation in host cells. Our data suggested that the activation of tachyzoite EGFR-like might facilitate the intracellular proliferation of N. caninum.

  7. Serological study of Neospora caninum infection in dogs in central China

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    Wang Shuai

    2016-01-01

    Full Text Available Neospora caninum is a protozoan parasite that causes abortion in cattle as well as reproduction problems and neurological disorders in dogs. Dogs are important in the epidemiology of N. caninum because they act as definitive hosts, shedding oocysts in the environment. To investigate the seroprevalence of N. caninum infection in dogs in central China, 1176 serum samples were collected from domestic dogs in Henan province, central China between March 2015 and February 2016 and tested for IgG antibody against N. caninum, using the indirect fluorescent antibody test (IFAT. The overall seroprevalence of N. caninum was nearly 15% (172/1176. No significant difference was observed between this seroprevalence according to sex and breed of dogs (p > 0.05. The infection rate in rural dogs (18% was higher (p < 0.05 than in urban dogs (11%. The prevalence of N. caninum infection in dogs increased (p < 0.05 with age. The results of the present study indicate the high prevalence of N. caninum antibodies in dogs in Henan province, central China. Sanitary conditions and animal health must be improved to prevent the transmission risk of N. caninum by dogs.

  8. Efficacy of toltrazuril and ponazuril against experimental Neospora caninum infection in mice.

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    Gottstein, B; Eperon, S; Dai, W J; Cannas, A; Hemphill, A; Greif, G

    2001-01-01

    Neosporosis is a disease affecting predominantly fetal development in cattle and dog hosts; and it may cause neuromuscular disfunction in infected newborn calves and pups. Predispositions--including, e.g. transient immunosuppression during pregnancy--may result in an increased dissemination of the parasite within the host or its offspring. Chemotherapeutic treatment of neosporosis may be an issue, provided that an appropriate drug is made available. In this respect, we describe the use of a mouse model for the evaluation of toltrazuril and ponazuril medication as a means of preventing parasite dissemination and subsequent formation of cerebral lesions. Toltrazuril- and ponazuril-treated mice were experimentally infected intraperitoneally (i.p.) with 2 x 10(6) Neospora caninum tachyzoites. The infection was monitored at three levels: clinically, by assessing symptoms, histologically, by assessing the occurrence of cerebral lesions and parasites by immunohistochemistry, and on the molecular level, by detection of parasite DNA using PCR. Chemotherapy using either toltrazuril or ponazuril, both applied in a drinking-water formulation (20 mg toltrazuril or ponazuril kg(-1) body weight day(-1)) completely prevented the formation of cerebral lesions in all treated animals, as assessed by immunohistochemistry. PCR analyses of these treated animals showed that DNA-detectability was reduced by 91% and 90% upon toltrazuril and ponazuril medication, respectively.

  9. Effects of Neospora caninum infection at mid-gestation on placenta in a pregnant mouse model.

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    López-Pérez, I C; Collantes-Fernández, E; Rojo-Montejo, S; Navarro-Lozano, V; Risco-Castillo, V; Pérez-Pérez, V; Pereira-Bueno, J; Ortega-Mora, L M

    2010-10-01

    Neospora caninum is one of the more-efficient transplacentally-transmitted organisms. The goal of the present study was to investigate the pathologic and immunologic changes that occur at the materno-fetal interphase in pregnant BALB/c mice infected with N. caninum at mid-gestation. Parasite DNA was detected in feto-placentary units 3 days post-infection (PI). On day 7 PI, the DNA detection level and parasite burden were significantly higher in the placentas than in the fetuses, which may indicate that the parasite is mainly multiplying in the placenta during the initial infection. In the spleens of infected dams, we observed an increase in IFN-γ, IL-10, and IL-4. However, only IL-4 was upregulated in placentas from the infected dams; this may enhance susceptibility to N. caninum at the materno-fetal interphase and favor transmission to the progeny. Finally, an increase in TNF-α expression in nested-PCR-positive placentas combined with necrosis may compromise the viability of the fetuses.

  10. Toxoplasma gondii and Neospora caninum in dogs from the state of Tocantins: serology and associated factors

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    Juliana Macedo Raimundo

    Full Text Available Abstract This study investigated occurrences of anti-Neospora caninum and anti-Toxoplasma gondii IgG antibodies by means of the enzyme-linked immunosorbent assay (ELISA and indirect immunofluorescence assay (IFAT, along with risk factors associated with toxoplasmosis and neosporosis, in 204 dogs from urban and rural areas of the municipality of Araguaína, state of Tocantins, Brazil. One hundred and thirty samples (63.7% were positive for T. gondii using ELISA: 57.1% and 70.7% in the urban and rural areas, respectively. The seropositivity frequency for T. gondii observed through IFAT was 57.4%, distributed between rural and urban areas as 62.6% and 52.4%, respectively. The factors associated with canine toxoplasmosis were age and breed (p<0.05. In relation to N. caninum, 88 samples (43.1% were positive, according to ELISA, distributed as 42.9% in urban areas and 43.3% in rural areas. Anti - N. caninum antibodies were detected through IFAT in 62 dogs (30.4%, distributed as 31.3% and 29.5% between rural and urban areas, respectively. Age and breed were associated with neosporosis occurrence (p<0.05 by IFAT. This study provides the first detection of IgG antibodies for canine toxoplasmosis and neosporosis in the state of Tocantins and highlights the importance of dogs in the epidemiological chain of these diseases.

  11. Risk factors for Toxoplasma gondii and Neospora caninum seropositivity in buffaloes in Paraiba State, Brazil

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    Arthur Willian de Lima Brasil

    Full Text Available Abstract The aims of this survey were to determine the frequency of anti-Toxoplasma gondii and anti-Neospora caninum antibodies and to identify the risk factors associated with seropositivity among buffaloes in the state of Paraíba, Brazil. This survey included 136 buffaloes belonging to 14 herds. To detect anti-T. gondii and anti-N. caninum antibodies, the indirect fluorescent antibody test (IFAT was used. Among the 136 samples analyzed, 17 (12.5% were positive for anti-T. gondii antibodies with titers ranging from 64 to 1,024, and 26 (19.1% for anti-N. caninum with titers from 200 to 1,600. Animals seropositive for both T. gondii and N. caninum were found in 10 of the 14 herds (71.4%. Semi-intensive management systems (odds ratio = 2.99 and presence of pigs (odds ratio = 4.33 were identified as risk factors for T. gondii and N. caninum, respectively. It can be suggested that T. gondii and N. caninum are widespread in buffaloes in Paraíba, and that additional surveys are needed in order to ascertain the importance of these agents for this species and for pigs, and the influence of the farming type on occurrences of seropositive animals.

  12. Detection of Neospora caninum-DNA in brain tissues from pigeons in Changchun, Jilin (China).

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    Du, Ling; Yang, Dongsheng; Zhai, Tao; Gong, Pengtao; Zhang, Xichen; Li, Jianhua

    2015-11-30

    Neospora caninum is an intracellular protozoan infecting many domestic and wild animals. The domestic chicken (Gallus domesticus) and the sparrow (Passer domesticus) are known as natural intermediate hosts of N. caninum, whereas the role of other birds such as pigeons is still unclear. In the present study, pigeon brain tissues collected in Jilin of China were screened by N. caninum specific-nested PCR to determine whether pigeons functioned as the natural intermediate hosts of N. caninum. The prevalences of N. caninum DNA and Toxoplasma gondii DNA among the brain samples were 30% (63/210) and 13.33% (28/210), respectively. One brain sample was co-infected with N. caninum and T. gondii in naturally infected pigeon. Of the 63 positive samples 42 could be assigned to the NC-PR genotype, 10 to the NC-1 genotypes and 5, 3 and 3 respectively to the each of the three new genotypes identified, indicating genetic polymorphism of N. caninum in pigeons in Jilin of China. The present study expanded the list of intermediate hosts of N. caninum to include pigeons which suggests that pigeons are involved in the transmission of the N. caninum. Copyright © 2015 Elsevier B.V. All rights reserved.

  13. Development of a diagnostic method for neosporosis in cattle using recombinant Neospora caninum proteins

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    Dong Jinhua

    2012-05-01

    Full Text Available Abstract Background Neosporosis is an infectious disease primarily of cattle and dogs, caused by intracellular parasite, Neospora caninum. Neosporosis appears to be a major cause of abortion in dairy cattle worldwide and causes to huge economic loss to dairy industry. Results Recombinant surface associated antigen 1 (NcSAG1, NcSAG1 related sequence 2 (NcSRS2 and the dense granule antigen 2 (NcGRA2 of N. caninum were expressed either in silkworm or in Escherichia coli and purified. The purified recombinant proteins bound to the N. caninum-specific antibodies in serum samples from infected cattle as revealed by an enzyme-linked immunosorbent assay (ELISA. By co-immobilizing these recombinant proteins, a novel indirect ELISA was developed for detection of neosporosis. With the use of 32 serum samples, comprising 12 positive serum samples and 20 negative serum samples, the sensitivity and specificity of the assay were found to be 91.7 and 100%, respectively. Seventy-two serum samples from dairy farms were also tested and one was diagnosed with neosporasis with both this method and a commercial assay. Conclusions A diagnostic method employing recombinant proteins of N. caninum was developed. The method showed high sensitivity and specificity. Diagnostic test with field serum samples suggested its applicability to the practical diagnosis of neosporosis.

  14. Detection of anti-Neospora caninum antibodies in Iranian native cattle

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    Jamal Gharekhani

    2014-12-01

    Full Text Available Neospora caninum is an Apicomplexan parasite which may cause abortion in cattle. This study investigated occurrences of antibodies against N. caninum in Iranian native cattle. From September 2010 to September 2011, blood samples (n=768 of native cows were collected randomly from different rural regions of Hamedan (n=400 and Kurdistan provinces (n=368 located to the western part of Iran. All the samples were evaluated for IgG antibodies against N. caninum using Enzyme Linked Immunosorbent Assay. The IgG antibodies to N. caninum were found in 14.2% (n=109/768 of serum samples (95% CI: 11.74 - 16.66. There was a significant difference between seropositivity and abortion history (p<0.0001, OR=2.9, unlike to age groups (p=0.105. This is the first report of N. caninum infection in Iranian native cattle. In conclusion, N. caninum is an important factor in abortion in Iranian native cattle. Further comprehensive studies and designing control strategies for improving management in cattle farms are highly recommended.

  15. Serological detection and epidemiology of Neospora caninum and Cryptosporidium parvum antibodies in cattle in southern Egypt.

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    Fereig, Ragab M; AbouLaila, Mahmoud Rezk; Mohamed, Samy G A; Mahmoud, Hassan Y A H; Ali, Alsagher O; Ali, Asmaa F; Hilali, Mosaad; Zaid, Anis; Mohamed, Adel Elsayed Ahmed; Nishikawa, Yoshifumi

    2016-10-01

    Neospora caninum and Cryptosporidium parvum are intracellular protozoan parasites that are distributed worldwide and of major economical concern in cattle industry. N. caninum can cause abortion storms and high culling rates, whereas C. parvum has zoonotic implications and can cause diarrhea in calves. There are currently no data on the prevalence of neosporosis and cryptosporidiosis in humans or animals in southern Egypt. Prevalence of these two infections was determined in a sample of cattle from two different areas in southern Egypt, Sohag and Qena, using enzyme-linked immunosorbent assay. A total 301 cattle were sampled, of which 18.9% were positive for N. caninum, 35.9% were positive for C. parvum and 10.0% were positive for both. Geographical location and breeding system were considered as potential risk factors for C. parvum infection. A higher prevalence of infection was identified on small scale farms, compared with larger, intensive systems, with a prevalence of 50.2% compared with 37.8%, respectively. Animals in Sohag had a significantly higher prevalence compared with Qena, with a seroprevalence of 46.1% compared with 31.6%, respectively. In brief, marked seroprevalence recorded in this study indicates a high incidence of N. caninum and C. parvum infections in cattle, and this necessitates the application of more effective strategies for combating these types of infections on farms in Egypt. Copyright © 2016 Elsevier B.V. All rights reserved.

  16. Fluorescent ester dye-based assays for the in vitro measurement of Neospora caninum proliferation.

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    Mota, Caroline M; Ferreira, Marcela D; Costa, Lourenço F; Barros, Patrício S C; Silva, Murilo V; Santiago, Fernanda M; Mineo, José R; Mineo, Tiago W P

    2014-09-15

    Techniques for the measurement of parasite loads in different experimental models have evolved throughout the years. The quantification of stained slides using regular cytological stains is currently the most common technique. However, this modality of evaluation is labor-intensive, and the interpretation of the results is subjective because the successes of the assays mainly rely on the abilities of the professionals involved. Moreover, the novel genetic manipulation techniques that are commonly applied for closely related Toxoplasma gondii have not yet been developed for Neospora caninum. Thus, we aimed to develop a simple protocol for parasite quantification using pre-stained N. caninum tachyzoites and fluorescent probes based on ester compounds (i.e., CFSE and DDAO). For this purpose, we employed a quantification procedure based on flow cytometry analysis. Pre-stained parasites were also examined with a fluorescent microscope, which revealed that both dyes were detectable. Direct comparison of the numbers of CFSE+ and DDAO+ cells to the values obtained with classical cytology techniques yielded statistically comparable results that also accorded with genomic DNA amplification results. Although the fluorescence emitted by DDAO was more intense and provided better discrimination between the populations of parasitized cells, CFSE+ tachyzoites were detected for several days. In conclusion, this study describes a simple, fast, low-cost and reproducible protocol for N. caninum quantification that is based on parasite pre-staining with fluorescent ester-based probes. Copyright © 2014 Elsevier B.V. All rights reserved.

  17. Toxoplasma gondii and Neospora caninum infections in goat abortions from Argentina.

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    Unzaga, J M; Moré, G; Bacigalupe, D; Rambeaud, M; Pardini, L; Dellarupe, A; De Felice, L; Gos, M L; Venturini, M C

    2014-12-01

    The aims of this study were to identify the occurrence of Toxoplasma gondii and Neospora caninum abortions in goats from Argentina by serological, macroscopical and microscopical examination and bioassay, and to characterize the obtained isolates by molecular techniques. For this purpose, 25 caprine fetal fluids, 18 caprine fetal brains and 10 caprine placentas from 8 dairy/meat goat farms from Argentina were analyzed. Gestational age of the aborted fetuses was determined in 18 cases. Protozoal infections were detected by at least one of the applied diagnostic techniques in 44% (11/25) of examined fetuses; specifically, 24% (6/25) were positive to T. gondii, 8% (2/25) were positive to N. caninum and 12% (3/25) were positive to both parasites. In this study IFAT titers were similarly distributed in younger and older fetuses. Macroscopical and microscopical examination of one placenta revealed chalky nodules in the fetal cotyledons and normal intercotyledonary areas, as well as necrosis and calcification of mesenchymal cells in villi. Tachyzoites were observed in peritoneal wash from 2 mice inoculated with brain and a pool of brain and placenta of two fetuses. Cell culture growth of tachyzoites was achieved from one inoculated mouse, and confirmed as T. gondii by PCR. The T. gondii isolate was identified as atypical or non-canonical by nested-PCR-RFLP. This is the first study that investigated the involvement of N. caninum and T. gondii in cases of goat abortion in Argentina. Copyright © 2014 Elsevier Ireland Ltd. All rights reserved.

  18. Anti-Neospora caninum antibodies among dairy cattle in a rural settlement, Paraná, Brazil

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    Shiguedy Katto

    2017-03-01

    Full Text Available The aim of the present study was to evaluate the seroprevalence of antibodies against Neospora caninum, obtained two years apart, among dairy cattle in a rural settlement in southern Brazil. Blood samples from 734 dairy cattle on 41 farms were collected at two different times: in 2012, 406 animals on 30 farms were used; and in 2014, 329 animals on 31 farms. Serum samples were obtained and were used to detect antibodies against N. caninum, by means of the indirect fluorescence assay (IFA. Animals with titers ? 100 were considered positive. The total serum prevalence of anti-N. caninum antibodies was 19.7% (145/736 among all the dairy cattle, comprising 23.1% (94/406 in 2012 and 15.5% (51/329 in 2014. Serum from 91 animals was tested in both trials: 11(12.1% showed positivity in 2012 and 10 (11% in 2014. The variables of age, sex and breed did not show any associations with seropositivity. Thus, we showed that the cattle in this settlement presented high levels of antibodies against N. caninum, and that IFA showed good efficacy for epidemiological studies.

  19. Flavonoids modulate the proliferation of Neospora caninum in glial cell primary cultures.

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    Matos, Rosan Barbosa de; Braga-de-Souza, Suzana; Pitanga, Bruno Pena Seara; Silva, Victor Diógenes Amaral da; Jesus, Erica Etelvina Viana de; Pinheiro, Alexandre Morales; Costa, Maria de Fátima Dias; El-Bacha, Ramon dos Santos; Ribeiro, Cátia Suse de Oliveira; Costa, Silvia Lima

    2014-12-01

    Neospora caninum (Apicomplexa; Sarcocystidae) is a protozoan that causes abortion in cattle, horses, sheep, and dogs as well as neurological and dermatological diseases in dogs. In the central nervous system of dogs infected with N. caninum, cysts were detected that exhibited gliosis and meningitis. Flavonoids are polyphenolic compounds that exhibit antibacterial, antiparasitic, antifungal, and antiviral properties. In this study, we investigated the effects of flavonoids in a well-established in vitro model of N. caninum infection in glial cell cultures. Glial cells were treated individually with 10 different flavonoids, and a subset of cultures was also infected with the NC-1 strain of N. caninum. All of the flavonoids tested induced an increase in the metabolism of glial cells and many of them increased nitrite levels in cultures infected with NC-1 compared to controls and uninfected cultures. Among the flavonoids tested, 3',4'-dihydroxyflavone, 3',4',5,7-tetrahydroxyflavone (luteolin), and 3,3',4',5,6-pentahydroxyflavone (quercetin), also inhibited parasitophorous vacuole formation. Taken together, our findings show that flavonoids modulate glial cell responses, increase NO secretion, and interfere with N. caninum infection and proliferation.

  20. Seroprevalence of Neospora Caninum Infection in Dairy Cattle in Tabriz, Northwest Iran

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    Gh Moghaddam

    2011-09-01

    Full Text Available Background: The aim of this study was to determine the seroprevalence of antibody to Neospora can­inum in healthy and aborted dairy cattle in Tabriz, capital of East-Azarbaijan in northwest of Iran.Methods: In this cross-sectional study serum samples were collected from 266 healthy and ab­orted Holestein-Feriesisnc cows from September 2008 to August 2009. The sera were analyzed to de­tect of antibody against N. caninum using the commercially ELISA kit.Results: Seroprevalence of antibody to N. caninum was 10.5% in Tabriz dairy cattle. Also the abortion rate in all cattle sampled was 33.6% but percentage of seropositive aborted cattle was 18.4%.Conclusion: Neosporosis could be one of the possible causes of abortion in dairy cattle in Tabriz and regarding the distribution in dogs as definitive host for the parasite, further studies in dog and cat­tle are recommended.

  1. In vitro and in vivo effects of the phytohormone inhibitor fluridone against Neospora caninum infection.

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    Ybañez, Rochelle Haidee D; Leesombun, Arpron; Nishimura, Maki; Matsubara, Ryuma; Kojima, Mikiko; Sakakibara, Hitoshi; Nagamune, Kisaburo; Nishikawa, Yoshifumi

    2016-08-01

    Neospora caninum causes abortion and stillbirth in cattle. Identification of effective drugs against this parasite remains a challenge. Previous studies have suggested that disruption of abscisic acid (ABA)-mediated signaling in apicomplexan parasites such as Toxoplasma gondii offers a new drug target. In this study, the ABA inhibitor, fluridone (FLU), was evaluated for its action against N. caninum. Production of endogenous ABA within N. caninum was confirmed by ultra-performance liquid chromatography-tandem quadruple mass spectrometry. Subsequently, FLU treatment efficacy was assessed using in vitro. Results revealed that FLU inhibited the growth of N. caninum and T. gondii in vitro (IC50 143.1±43.96μM and 330.6±52.38μM, respectively). However, FLU did not affect parasite replication at 24h post-infection, but inhibited egress of N. caninum thereafter. To evaluate the effect of FLU in vivo, N. caninum-infected mice were treated with FLU for 15days. FLU treatment appeared to ameliorate acute neosporosis induced by lethal parasite challenge. Together, our data shows that ABA might control egress in N. caninum. Therefore, FLU has potential as a candidate drug for the treatment of acute neosporosis. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.

  2. The chloramphenicol acetyltransferase vector as a tool for stable tagging of Neospora caninum.

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    Pereira, Luiz Miguel; Yatsuda, Ana Patrícia

    2014-09-01

    Neospora caninum is an obligate intracellular Apicomplexa, a phylum where one of the current methods for functional studies relies on molecular genetic tools. For Toxoplasma gondii, the first method described, in 1993, was based on resistance against chloramphenicol. As in T. gondii, we developed a vector constituted of the chloramphenicol acetyltransferase gene (CAT) flanked by the N. caninum dihydrofolate reductase-thymidylate synthase (DHFR-TS) 5' coding sequence flanking region. Five weeks after transfection and under the selection of chloramphenicol the expression of CAT increased compared to the wild type and the resistance was retained for more than one year. Between the stop codon of CAT and the 3' UTR of DHFR, a Lac-Z gene controlled by the N. caninum tubulin 5' coding sequence flanking region was ligated, resulting in a vector with a reporter gene (Ncdhfr-CAT/NcTub-tetO/Lac-Z). The stability was maintained through an episomal pattern for 14 months when the tachyzoites succumbed, which was an unexpected phenomenon compared to T. gondii. Stable parasites expressing the Lac-Z gene allowed the detection of tachyzoites after invasion by enzymatic reaction (CPRG) and were visualised macro- and microscopically by X-Gal precipitation and fluorescence. This work developed the first vector for stable expression of proteins based on chloramphenicol resistance and controlled exclusively by N. caninum promoters. Copyright © 2014 Elsevier B.V. All rights reserved.

  3. Mucosal immunization confers long-term protection against intragastrically established Neospora caninum infection.

    Science.gov (United States)

    Ferreirinha, Pedro; Correia, Alexandra; Teixeira-Coelho, Maria; Osório, Hugo; Teixeira, Luzia; Rocha, António; Vilanova, Manuel

    2016-12-07

    Neospora caninum is an obligate intracellular protozoan parasite responsible for heavy economic losses in dairy and beef cattle farms worldwide. Although vaccination is widely regarded as the preferable strategy to prevent neosporosis no commercial vaccine is currently available. We have previously shown that intranasal immunization with an N. caninum antigen extract enriched in hydrophobic proteins plus CpG adjuvant protected mice against intragastrically established neosporosis. Nevertheless, the antigen specificity as well as the long-term protective effect of this immunization strategy were not determined. Here, we show that the protective effect of this intranasal immunization procedure lasted for at least 20weeks. Protection was accompanied by long-lasting elevated levels of parasite-specific serum IgG and intestinal IgA. Moreover, spleen and mesenteric lymph node cells obtained from non-infected long-term immunized mice responded by producing interferon-γ following in vitro parasite-antigen recall. Analysis of serum IgG and intestinal IgA antibody reactivity in immunized mice identified dense granule antigen 7 (NcGRA7) and microneme associated protein 1 (NcMIC1) as immunodominant antigens respectively recognized by those antibody fractions. In summary, this work shows that a previously reported mucosal immunization strategy against N. caninum infection established through the gastrointestinal tract is effective in the long term. Copyright © 2016 Elsevier Ltd. All rights reserved.

  4. Development of a diagnostic method for neosporosis in cattle using recombinant Neospora caninum proteins

    Science.gov (United States)

    2012-01-01

    Background Neosporosis is an infectious disease primarily of cattle and dogs, caused by intracellular parasite, Neospora caninum. Neosporosis appears to be a major cause of abortion in dairy cattle worldwide and causes to huge economic loss to dairy industry. Results Recombinant surface associated antigen 1 (NcSAG1), NcSAG1 related sequence 2 (NcSRS2) and the dense granule antigen 2 (NcGRA2) of N. caninum were expressed either in silkworm or in Escherichia coli and purified. The purified recombinant proteins bound to the N. caninum-specific antibodies in serum samples from infected cattle as revealed by an enzyme-linked immunosorbent assay (ELISA). By co-immobilizing these recombinant proteins, a novel indirect ELISA was developed for detection of neosporosis. With the use of 32 serum samples, comprising 12 positive serum samples and 20 negative serum samples, the sensitivity and specificity of the assay were found to be 91.7 and 100%, respectively. Seventy-two serum samples from dairy farms were also tested and one was diagnosed with neosporasis with both this method and a commercial assay. Conclusions A diagnostic method employing recombinant proteins of N. caninum was developed. The method showed high sensitivity and specificity. Diagnostic test with field serum samples suggested its applicability to the practical diagnosis of neosporosis. PMID:22558916

  5. First Characterization of the Neospora caninum Dense Granule Protein GRA9

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    Margret Leineweber

    2017-01-01

    Full Text Available The obligate intracellular apicomplexan parasite Neospora caninum (N. caninum is closely related to Toxoplasma gondii (T. gondii. The dense granules, which are present in all apicomplexan parasites, are important secretory organelles. Dense granule (GRA proteins are released into the parasitophorous vacuole (PV following host cell invasion and are known to play important roles in the maintenance of the host-parasite relationship and in the acquisition of nutrients. Here, we provide a detailed characterization of the N. caninum dense granule protein NcGRA9. The in silico genomic organization and key protein characteristics are described. Immunofluorescence-based localization studies revealed that NcGRA9 is located in the dense granules and is released into the interior of the PV following host cell invasion. Immunogold-electron microscopy confirmed the dense granule localization and showed that NcGRA9 is associated with the intravacuolar network. In addition, NcGRA9 is found in the “excreted secreted antigen” (ESA fraction of N. caninum. Furthermore, by analysing the distribution of truncated versions of NcGRA9, we provide evidence that the C-terminal region of this protein is essential for the targeting of NcGRA9 into the dense granules of N. caninum, and the truncated proteins show reduced secretion.

  6. Comparison of an ELISA assay for the detection of adhesive/invasive Neospora caninum tachyzoites

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    Luiz Miguel Pereira

    Full Text Available Neospora caninum belongs to the phylum Apicomplexa, the causative agent of neosporosis, which leads to economic impacts on cattle production. A common feature among apicomplexan parasites is the invasive process driven mostly by the parasite. As a first evaluation of candidate molecules that play a possible role by interfering in this invasive process, the in vitro invasion assay is a fast and direct way to screen future agonists or antagonists. This work involved the development of a new cell culture ELISA and transient β-galactosidase activity applied to the semi-quantitative detection of N. caninum in Vero cell culture. Cell culture ELISA is based on histochemistry and immunology, resulting in a colorimetric reaction. The β-galactosidase activity was obtained by the transient transfection of the lacZ gene under control of RPS13 promoter of N. caninum. These methods were used to evaluate the effects of temperature (37°C and 85°C on the invasion and adhesion of tachyzoites. The three tested methods (real time PCR, β-galactosidase activity and ELISA showed a similar pattern, indicating that different methods may be complementary.

  7. Activities of 11-Azaartemisinin and N-Sulfonyl Derivatives against Neospora caninum and Comparative Cytotoxicities.

    Science.gov (United States)

    Harmse, Rozanne; Wong, Ho Ning; Smit, Frans J; Müller, Joachim; Hemphill, Andrew; N'Da, David D; Haynes, Richard K

    2017-12-19

    Neosporosis caused by the apicomplexan parasite Neospora caninum is an economically important disease that induces abortion in dairy and beef cattle. There are no vaccines or drugs available on the market for control or treatment of the disease in bovines. The peroxide artemisinin and its derivatives used clinically for treatment of malaria are active against N. caninum and other apicomplexan parasites. We have now evaluated the activities of the readily accessible and chemically robust 11-azaartemisinin 5 and selected N-sulfonyl derivatives prepared as described in the accompanying paper against N. caninum tachyzoites grown in infected human foreskin fibroblasts. Azaartemisinin elicited an IC 50 value of 150 nm, and the 2',5'-dichloro-3'-thienylsulfonyl-11-azaartemisinin 17 was found to be the most active, with an IC 50 value of 40 nm. Comparison with normal human fetal lung fibroblasts HFLF WI-38 revealed relatively benign cytotoxicity. The compounds were also screened in vitro against TK-10 (renal), UACC-62 (melanoma) and MCF-7 (breast) cancer cell lines; overall, in line with activities against HFLF cells, most compounds in the series were found to be inactive. © 2017 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.

  8. Toxoplasma gondii and Neospora caninum in wild small mammals: Seroprevalence, DNA detection and genotyping.

    Science.gov (United States)

    Machačová, Tereza; Ajzenberg, Daniel; Žákovská, Alena; Sedlák, Kamil; Bártová, Eva

    2016-06-15

    Generally, rodents and other small mammals are considered as one of the sources of Toxoplasma gondii or Neospora caninum infection for cats and dogs as the definitive hosts of these two parasites, respectively. The aim of the study was to find out the prevalence of these two parasites in wild small mammals from the Czech Republic and to characterize T. gondii isolates by methods of molecular biology. A total of 621 wild small mammals were caught in the Czech Republic during years 2002-2014. Antibodies to T. gondii were detected by latex agglutination test in six (2.5%) of 240 small mammals (in two A. agrarius and four A. flavicollis). Antibodies to N. caninum were detected by commercially available competitive-inhibition enzyme-linked immunosorbent assay in one A. flavicolis (0.4%). Three of 427 (0.7%) liver samples were positive for T. gondii by PCR while negative for N. caninum. All embryo samples (n=102) were negative for both T. gondii and N. caninum. The three liver samples positive for T. gondii DNA (two from A. flavicollis and one from A. sylvaticus) were genotyped by 15 microsatellite markers and characterized as type II. To our knowledge, this is the first information about genetic characterization of T. gondii isolates in small mammals from Europe and the first detection of N. caninum antibodies in wild rodents from the Czech Republic. Copyright © 2016 Elsevier B.V. All rights reserved.

  9. In vitro effects of new artemisinin derivatives in Neospora caninum-infected human fibroblasts.

    Science.gov (United States)

    Müller, Joachim; Balmer, Vreni; Winzer, Pablo; Rahman, Mahbubur; Manser, Vera; Haynes, Richard K; Hemphill, Andrew

    2015-07-01

    From a panel of 34 artemisinin derivatives tested in vitro, artemisone, GC007 and GC012 were most efficacious at inhibiting Neospora caninum replication (IC50 values of 3-54nM), did not notably impair the invasiveness of tachyzoites and were non-toxic for human foreskin fibroblasts (HFFs). Transmission electron microscopy of drug-treated N. caninum-infected HFFs demonstrated severe alterations in the parasite cytoplasm, changes in the composition of the matrix of the parasitophorous vacuole (PV) and diminished integrity of the PV membrane. To exert parasiticidal activity, parasites had to be cultured continuously in the presence of 5μM artemisone or GC007 for 3 weeks. N. caninum tachyzoites readily adapted to a stepwise increase in concentrations (0.5-10μM) of GC012, but not to artemisone or GC007. Drugs induced the expression of elevated levels of NcBAG1 and NcSAG4 mRNA, but only NcBAG1 could be detected by immunofluorescence. Thus, artemisinin derivatives represent interesting leads that should be investigated further. Copyright © 2015 Elsevier B.V. and the International Society of Chemotherapy. All rights reserved.

  10. Spatial analysis of Neospora caninum distribution in dairy cattle from Sweden

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    Jenny Frössling

    2008-11-01

    Full Text Available The national herd prevalence and spatial distribution of Neospora caninum infected dairy herds in Sweden were investigated. The study was based on a bulk milk survey comprising samples from 2,978 herds. Test-positive herds were found in all parts of Sweden and the overall prevalence of test-positive herds was 8.3% (95% confidence interval = 7.3-9.3%. The presence of spatial autocorrelation was tested using the Moran’s I test. Possible clusters of test-positive herds were identified by applying the local indicator of spatial association (LISA test statistic and the spatial scan statistic. Analysis based on data aggregated by postal code areas as well as analysis based on exact coordinates identified significant clusters of high prevalence in the middle parts of Sweden and low prevalence in the south. This was not expected considering the results from other European studies of N. caninum in cattle. However, the findings are supported by the distribution of previously known case herds.

  11. Neospora caninum surface antigen (p40) is a potential diagnostic marker for cattle neosporosis.

    Science.gov (United States)

    He, Pengfei; Li, Jianhua; Gong, Pengtao; Liu, Chengwu; Zhang, Guocai; Yang, Ju; Tuo, Wenbin; Yang, Bintong; Zhang, Xichen

    2013-05-01

    Neospora caninum is an intracellular protozoan that infects domestic and wild canids as well as many warm-blooded animals as shown by the isolation of viable parasites. The effectiveness of diagnostic tests for detecting specific antibodies against N. caninum is hampered by potential cross-reaction with other Coccidia. So, there is currently an urgent need for a sensitive and specific diagnostic assay for detecting N. caninum in animals. The N. caninum 40-kD surface antigen (p40), similar to NcSAG1 and NcSRS2, was shown to belong to surface antigen super family and thus represents an excellent marker for the diagnosis of neosporosis. In order to test the hypothesis, recombinant Ncp40 (rNcp40) was expressed in Escherichia coli, and an indirect ELISA test was developed using recombinant NCp40 antigen for N. caninum serodiagnosis. The antigen used in this study did not have cross-reactivity with anti-Toxoplasma gondii serum. Anti-p40 antibodies were detected by ELISA in the sera of Yellow cattle and were compared with (IFAT). Optimal sensitivity and specificity (98.2 and 98.6 %) were identified by IFAT. Additionally, 37 positive sera of T. gondii were detected and there was no significant difference with the negative serum of N. caninum. The rNcp40 ELISA developed here provides a specific and sensitive assay for detecting neosporosis in cattle.

  12. Development of a diagnostic method for neosporosis in cattle using recombinant Neospora caninum proteins.

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    Dong, Jinhua; Otsuki, Takahiro; Kato, Tatsuya; Park, Enoch Y

    2012-05-04

    Neosporosis is an infectious disease primarily of cattle and dogs, caused by intracellular parasite, Neospora caninum. Neosporosis appears to be a major cause of abortion in dairy cattle worldwide and causes to huge economic loss to dairy industry. Recombinant surface associated antigen 1 (NcSAG1), NcSAG1 related sequence 2 (NcSRS2) and the dense granule antigen 2 (NcGRA2) of N. caninum were expressed either in silkworm or in Escherichia coli and purified. The purified recombinant proteins bound to the N. caninum-specific antibodies in serum samples from infected cattle as revealed by an enzyme-linked immunosorbent assay (ELISA). By co-immobilizing these recombinant proteins, a novel indirect ELISA was developed for detection of neosporosis. With the use of 32 serum samples, comprising 12 positive serum samples and 20 negative serum samples, the sensitivity and specificity of the assay were found to be 91.7 and 100%, respectively. Seventy-two serum samples from dairy farms were also tested and one was diagnosed with neosporasis with both this method and a commercial assay. A diagnostic method employing recombinant proteins of N. caninum was developed. The method showed high sensitivity and specificity. Diagnostic test with field serum samples suggested its applicability to the practical diagnosis of neosporosis.

  13. Neosporosis in Beagle dogs: clinical signs, diagnosis, treatment, isolation and genetic characterization of Neospora caninum.

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    Dubey, J P; Vianna, M C B; Kwok, O C H; Hill, D E; Miska, K B; Tuo, W; Velmurugan, G V; Conors, M; Jenkins, M C

    2007-11-10

    Clinical neosporosis was diagnosed in a litter of five pups born to a Beagle bitch from Virginia, USA. Four of the pups developed limb weakness starting at 4 weeks of age. The dogs were suspected to have neosporosis based on clinical signs and empirically treated with Clindamycin (75 mg, oral, twice daily, total 150 mg) starting at 9 weeks of age and the dosage was doubled at 13 weeks of age. Antibodies to Neospora caninum were detected in sera of the dam and pups when first tested serologically at the age of 4 months. The owner donated the pup with the worst clinical signs and the dam for research; both dogs were euthanized. Viable N. caninum was isolated in gamma interferon gene knock out (KO) mice and in cell culture from the pup killed at 137 days of age. Tissue cysts, but no tachyzoites, were found in histological sections of brain and muscles. The isolate was also identified as N. caninum by PCR and sequence analysis and designated NC-9. N. caninum was neither isolated by bioassay in KO mice nor found in histological sections of tissues of the bitch. Clinical signs in the remaining three pups improved considerably after a 6-month treatment with Clindamycin; N. caninum antibody titers were still persistent in these pups at 23 months of age. Results indicate that medication with Clindamycin can improve clinical condition but not eliminate N. caninum infection.

  14. Transcriptome and Histopathological Changes in Mouse Brain Infected with Neospora caninum

    Science.gov (United States)

    Nishimura, Maki; Tanaka, Sachi; Ihara, Fumiaki; Muroi, Yoshikage; Yamagishi, Junya; Furuoka, Hidefumi; Suzuki, Yutaka; Nishikawa, Yoshifumi

    2015-01-01

    Neospora caninum is a protozoan parasite that causes neurological disorders in dogs and cattle. It can cause nonsuppurative meningoencephalitis and a variety of neuronal symptoms are observed, particularly in dogs. However, the pathogenic mechanism, including the relationship between the parasite distribution and the clinical signs, is unclear. In this study, to understand the pathogenic mechanism of neosporosis, parasite distribution and lesions were assessed in the brain of mice infected with N. caninum (strain Nc-1). Host gene expression was also analyzed with RNA sequencing (RNA-Seq). The histopathological lesions in the frontal lobe and the medulla oblongata were significantly more severe in symptomatic mice than in asymptomatic mice, although no association between the severity of the lesions and parasite numbers was found. In infected mice, the expression of 772 mouse brain genes was upregulated. A GOstat analysis predicted that the upregulated genes were involved in the host immune response. Genes whose expression correlated positively and negatively with parasite numbers were involved in the host immune response, and neuronal morphogenesis and lipid metabolic processes, respectively. These results suggest that changes in the gene expression profile associated with neuronal functions as well as immune responses can contribute to the pathogenesis in N. caninum-infected animals. PMID:25604996

  15. ANTIBODIES LEVELS AGAINST Neospora caninum DURING PREGNANCY IN NATURALLY INFECTED DAIRY COWS

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    Ana Maria Antonello

    2015-10-01

    Full Text Available Neosporosis is one of the major causes of reproductive failure in bovine around the world. The period of gestation, in which the infection or the recrudescence of bradzoites forms occurs and reflects in the antibodies levels, is one of the factors that define pregnancy future. Therefore, this study aimed to determine the serological profile during pregnancy of naturally infected females. To do that, serological samples of 25 Holstain Friesian cows were collected from artificial insemination day until parturition, in monthly intervals. These samples were tested by indirect immunofluorescence for IgG anti-Neospora caninum. Of the 25 animals, only 13 were used in the analysis, because they were seropositive since the beginning or seroconverted during pregnancy. The results showed a gradual increase in antibody levels along pregnancy, more visible at the end of the period. We observed a significant difference in antibodies title between initial and final periods of pregnancy, which suggests the reactivation of bradzoite forms present in tissues during pregnancy. These results reinforce the knowledge of antibodies fluctuation along pregnancy, affected by N. caninum reinfection or reactivation. This serological knowledge is important to Neosporosis pathogeny, epidemiology and diagnostic.

  16. Seroepidemiological survey of Neospora caninum and its risk factors in farm dogs in Nakuru district, Kenya

    Science.gov (United States)

    Okumu, Tequiero Abuom; Munene, John Njenga; Wabacha, James; Tsuma, Victor; Leeuwen, John Van

    2016-01-01

    Aim: The objective of this study was to determine the seroprevalence of Neospora caninum (NC) and its risk factors in farm dogs in Kenya. Materials and Methods: As part of a longitudinal study on dairy cattle abortion in 2010 in Kenya, serum samples were collected from 84 dogs in 53 randomly selected dairy cattle farms to determine the seroprevalence and risk factors of seropositivity for NC. Results: 15 (17.9%) of the dogs were seropositive to NC antibodies, and at least one seropositive dog was found in 12 (22.6%) of the 53 farms. The final multivariable logistic regression model identified free-roaming as the only factor significantly associated with seropositivity (odds ratio=4.48; p=0.03). Conclusion: The findings of this study indicate that canine neosporosis does exist in Kenya and that farmers should restrict their dogs from roaming to reduce the risk of their dogs becoming a reservoir for NC. More studies need to be carried out to determine the reproductive effects of NC on dairy cattle in Kenya. PMID:27847430

  17. Seroprevalence of Neospora caninum in dairy cattle from north-west and centre of Romania

    Science.gov (United States)

    Gavrea, R.R.; Iovu, A.; Losson, B.; Cozma, V.

    2011-01-01

    Neosporosis is a disease that mainly affects cattle in both dairy and beef herds. The main definitive host of this parasite is the dog. Since 1984 and its first description a large number of data were published worldwide on this parasite. In Romania, the research regarding this parasite is limited. The purpose of this study was to determine the seroprevalence of Neospora caninum infection in dairy cattle from six regions in north-western Romania and to evaluate the intensity of infection in different animals groups. A total number of 901 samples (862 sera from adult cows and 39 sera from calves) were collected from dairy farms and were screened for the presence of specific IgG anti-bodies using an enzyme-linked immunosorbent assay (ELISA). The overall seroprevalence for neosporosis was 34.6%. In adult cows and calves seroprevalences reached 34.8% (300/862) and 30.8% for calves (12/39) respectively. In cattle which had previously aborted, seroprevalence was 40.9%. These results indicate that N. caninum infection is widespread among animals reared in dairy systems from Romania and a program for farmer training and a strategy for reducing the economic impact of the disease are needed. PMID:22091468

  18. Transplacental transmission of Neospora caninum in naturally infected small ruminants from northeastern Brazil

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    Annelise C.B.T. Nunes

    Full Text Available ABSTRACT: Toxoplasma gondii and Neospora caninum are causative agents of abortion in sheep and goats. Thus, the present study aimed to describe the transplacental transmission of these protozoans in small ruminants of northeastern Brazil. Seventeen fetuses (6 goats and 11 sheep from farms with history of abortion were necropsied and samples were collected from different tissues (brain, liver, lung, kidney and heart. The samples were analyzed by PCR, histopathology (HP and immunohistochemistry (IHC to evaluate whether T. gondii and/or N. caninum infection were the cause of abortion. None of the samples was positive for T. gondii according to PCR and IHC results. Some brain, liver, lung, kidney and heart samples of goat fetuses were positive for N. caninum by PCR. In the histopathology, mild mononuclear infiltration and necrosis with calcification were observed in the liver and brain of one goat fetus, respectively, that also was positive for N. caninum by PCR and IHC. The results confirmed vertical transmission of N. caninum in naturally infected goats of northeastern, Brazil.

  19. Neospora caninum serostatus in dairy cattle of the Northern plains of Antioquia, Colombia

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    Jenny Chaparro G

    2016-09-01

    Full Text Available Objectives. To determine Neospora caninum seroprevalence in nonvaccinated dairy cattle from the Northern plains of Antioquia. Materials and methods. A cross-sectional study was conducted to determine the prevalence of neosporosis in a major dairy area of Colombia. Blood samples were collected from 1003 dairy cattle in 29 herds located in the municipality of San Pedro de los Milagros, in Antioquia. N. caninum antibody levels were measured by an enzymatic immunoassay (ELISA and the results classified as positive or negative. Results. Seropositive cattle were observed in all herds, with a prevalence ranging from 7 to 97% and a mean (±S.E of 37.1% (±4.2. The distribution of seropositive animals by age groups of <1, 1-2, 2-3 and ≥3 years old was 25.5, 30.3, 46.1 and 39.1%, respectively. Conclusions. There is a high seroprevalence of N. caninum in the main dairy cattle area of Antioquia. The large variation among herds suggests the presence of mayor risk factors whose identification would be essential to establish control programs. Considering that any seropositive cow has a greater risk to abort than uninfected mates, future studies should address the epidemiology of abortions that can be attributed to neosporosis and the type of control strategies that could be implemented.

  20. Seroprevalence of Neospora caninum and Toxoplasma gondii in exotic ruminants and camelids in the Czech Republic.

    Science.gov (United States)

    Bártová, Eva; Kobédová, Kateřina; Lamka, Jiří; Kotrba, Radim; Vodička, Roman; Sedlák, Kamil

    2017-07-01

    Neospora caninum and Toxoplasma gondii are the protozoan parasites with definitive hosts from order Carnivora. Due to vertical transmission, both parasites can cause abortions and neonatal mortality that lead to significant productive and economic losses in the domestic ruminants. The aim of this study was to describe N. caninum and T. gondii seroprevalence in the group of frequently farmed captive exotic ruminants (n = 184) including Bovidae (barbary sheep, bezoar goat, common eland, American bison, water buffalo, and yak) and Camelidae (bactrian camel, guanaco, llama, and alpaca). Antibodies were tested by indirect fluorescent antibody test (IFAT) and enzyme-linked immunosorbent assay (ELISA). Higher prevalence of T. gondii antibodies (31% in IFAT and 52% in ELISA) was detected compared to N. caninum (24% in IFAT and 17% in cELISA). Mixed infection was found in 18 (10%) and 22 (12%) animals by IFAT and ELISA, respectively. Higher seroprevalence of both N. caninum and T. gondii was found in Camelidae compared to Bovidae. To author knowledge, this is the first detection of T. gondii and N. caninum antibodies in common elands and bezoar goats.

  1. Toxoplasma gondii and Neospora caninum seroprevalences in domestic South American camelids of the Peruvian Andes.

    Science.gov (United States)

    Chávez-Velásquez, Amanda; Aguado-Martínez, Adriana; Ortega-Mora, Luis M; Casas-Astos, Eva; Serrano-Martínez, Enrique; Casas-Velásquez, Gina; Ruiz-Santa-Quiteria, Jose A; Alvarez-García, Gema

    2014-10-01

    The objective of this study was to investigate the presence of Toxoplasma gondii- and Neospora caninum-specific antibodies in domestic South American camelids (SAC) (llamas and alpacas) from the Peruvian Andes through a cross-sectional study. A wide panel of serum samples collected from 1,845 llamas and 2,874 alpacas from the two main SAC production areas of Peru was selected. Immunofluorescence antibody technique was employed to detect and titrate specific anti-T. gondii and anti-N. caninum immunoglobulins G in serum samples. The association between T. gondii and N. caninum seroprevalence and the geographical origin (Central and South Peruvian Andes) was evaluated. Anti-T. gondii antibodies were found in 460 (24.9 %) llamas and 706 (24.6 %) alpacas, whereas anti-N. caninum antibodies were detected in 153 (8.3 %) llamas and 425 (14.8 %) alpacas. Toxoplasma gondii infection was strongly associated with the South Peruvian Andes where moderate climate conditions, larger human population, compared to the Central region, and the presence of wildlife definitive hosts could favor horizontal transmission to SAC. In contrast, N. caninum infection was not associated with the geographical region. These results indicate that T. gondii and N. caninum infections are highly and moderately widespread, respectively, in both species of domestic SAC studied in the sampled areas and appropriate control measures should be undertaken to reduce the prevalence of both parasitic infections.

  2. Seroepidemiology of Sarcocystis neurona and Neospora hughesi infections in domestic donkeys (Equus asinus) in Durango, Mexico.

    Science.gov (United States)

    Alvarado-Esquivel, Cosme; Howe, Daniel K; Yeargan, Michelle R; Alvarado-Esquivel, Domingo; Alfredo Zamarripa-Barboza, José; Dubey, Jitender P

    2017-01-01

    There is currently no information regarding Sarcocystis neurona and Neospora hughesi infections in donkeys in Mexico. Here, we determined the presence of antibodies against S. neurona and N. hughesi in donkeys in the northern Mexican state of Durango. Serum samples of 239 domestic donkeys (Equus asinus) were assayed for S. neurona and N. hughesi antibodies using home-made enzyme-linked immunoassays; six (2.5%) of the 239 donkeys tested seropositive for S. neurona. The seroprevalence of S. neurona infection was comparable among donkeys regardless of their origin, health status, or sex. Multivariate analysis showed that seropositivity to S. neurona was associated with increased age (OR = 2.95; 95% CI: 1.11-7.82; p = 0.02). Antibodies to N. hughesi were found in two (0.8%) of the 239 donkeys. Both exposed donkeys were healthy, 3- and 6-year-old females. This is the first evidence of S. neurona and N. hughesi infections in donkeys in Mexico. © C. Alvarado-Esquivel et al., published by EDP Sciences, 2017.

  3. Seroepidemiology of Sarcocystis neurona and Neospora hughesi infections in domestic donkeys (Equus asinus in Durango, Mexico

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    Alvarado-Esquivel Cosme

    2017-01-01

    Full Text Available There is currently no information regarding Sarcocystis neurona and Neospora hughesi infections in donkeys in Mexico. Here, we determined the presence of antibodies against S. neurona and N. hughesi in donkeys in the northern Mexican state of Durango. Serum samples of 239 domestic donkeys (Equus asinus were assayed for S. neurona and N. hughesi antibodies using home-made enzyme-linked immunoassays; six (2.5% of the 239 donkeys tested seropositive for S. neurona. The seroprevalence of S. neurona infection was comparable among donkeys regardless of their origin, health status, or sex. Multivariate analysis showed that seropositivity to S. neurona was associated with increased age (OR = 2.95; 95% CI: 1.11–7.82; p = 0.02. Antibodies to N. hughesi were found in two (0.8% of the 239 donkeys. Both exposed donkeys were healthy, 3- and 6-year-old females. This is the first evidence of S. neurona and N. hughesi infections in donkeys in Mexico.

  4. Cryptic Leishmania infantum infection in Italian HIV infected patients

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    Rubino Raffaella

    2009-12-01

    Full Text Available Abstract Background Visceral leishmaniasis (VL is a protozoan diseases caused in Europe by Leishmania (L. infantum. Asymptomatic Leishmania infection is more frequent than clinically apparent disease. Among HIV infected patients the risk of clinical VL is increased due to immunosuppression, which can reactivate a latent infection. The aims of our study were to assess the prevalence of asymptomatic L. infantum infection in HIV infected patients and to study a possible correlation between Leishmania parasitemia and HIV infection markers. Methods One hundred and forty-five HIV infected patients were screened for the presence of anti-Leishmania antibodies and L. infantum DNA in peripheral blood. Statistical analysis was carried out by using a univariate regression analysis. Results Antibodies to L. infantum were detected in 1.4% of patients. L. infantum DNA was detected in 16.5% of patients. Significant association for PCR-Leishmania levels with plasma viral load was documented (p = 0.0001. Conclusion In our area a considerable proportion of HIV infected patients are asymptomatic carriers of L. infantum infection. A relationship between high HIV viral load and high parasitemic burden, possibly related to a higher risk of developing symptomatic disease, is suggested. PCR could be used for periodic screening of HIV patients to individuate those with higher risk of reactivation of L. infantum infection.

  5. Intergenic and external transcribed spacers of ribosomal RNA genes in lizard-infecting Leishmania: molecular structure and phylogenetic relationship to mammal-infecting Leishmania in the subgenus Leishmania (Leishmania

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    Orlando Tereza C

    2002-01-01

    Full Text Available To establish the relationships of the lizard- and mammal-infecting Leishmania, we characterized the intergenic spacer region of ribosomal RNA genes from L. tarentolae and L. hoogstraali. The organization of these regions is similar to those of other eukaryotes. The intergenic spacer region was approximately 4 kb in L. tarentolae and 5.5 kb in L. hoogstraali. The size difference was due to a greater number of 63-bp repetitive elements in the latter species. This region also contained another element, repeated twice, that had an inverted octanucleotide with the potential to form a stem-loop structure that could be involved in transcription termination or processing events. The ribosomal RNA gene localization showed a distinct pattern with one chromosomal band (2.2 Mb for L. tarentolae and two (1.5 and 1.3 Mb for L. hoogstraali. The study also showed sequence differences in the external transcribed region that could be used to distinguish lizard Leishmania from the mammalian Leishmania. The intergenic spacer region structure features found among Leishmania species indicated that lizard and mammalian Leishmania are closely related and support the inclusion of lizard-infecting species into the subgenus Sauroleishmania proposed by Saf'janova in 1982.

  6. Comparative genomics of the apicomplexan parasites Toxoplasma gondii and neospora caninum: Coccidia differing in host range and transmission strategy

    KAUST Repository

    Reid, Adam James

    2012-03-22

    Toxoplasma gondii is a zoonotic protozoan parasite which infects nearly one third of the human population and is found in an extraordinary range of vertebrate hosts. Its epidemiology depends heavily on horizontal transmission, especially between rodents and its definitive host, the cat. Neospora caninum is a recently discovered close relative of Toxoplasma, whose definitive host is the dog. Both species are tissue-dwelling Coccidia and members of the phylum Apicomplexa; they share many common features, but Neospora neither infects humans nor shares the same wide host range as Toxoplasma, rather it shows a striking preference for highly efficient vertical transmission in cattle. These species therefore provide a remarkable opportunity to investigate mechanisms of host restriction, transmission strategies, virulence and zoonotic potential. We sequenced the genome of N. caninum and transcriptomes of the invasive stage of both species, undertaking an extensive comparative genomics and transcriptomics analysis. We estimate that these organisms diverged from their common ancestor around 28 million years ago and find that both genomes and gene expression are remarkably conserved. However, in N. caninum we identified an unexpected expansion of surface antigen gene families and the divergence of secreted virulence factors, including rhoptry kinases. Specifically we show that the rhoptry kinase ROP18 is pseudogenised in N. caninum and that, as a possible consequence, Neospora is unable to phosphorylate host immunity-related GTPases, as Toxoplasma does. This defense strategy is thought to be key to virulence in Toxoplasma. We conclude that the ecological niches occupied by these species are influenced by a relatively small number of gene products which operate at the host-parasite interface and that the dominance of vertical transmission in N. caninum may be associated with the evolution of reduced virulence in this species.

  7. Variables Associated with Infections of Cattle by Brucella abortus., Leptospira spp. and Neospora spp. in Amazon Region in Brazil.

    Science.gov (United States)

    Chiebao, D P; Valadas, S Y O B; Minervino, A H H; Castro, V; Romaldini, A H C N; Calhau, A S; De Souza, R A B; Gennari, S M; Keid, L B; Soares, R M

    2015-10-01

    The frequency of Neospora spp., Leptospira spp. and Brucella abortus infections in adult cattle was determined in herds of the State of Pará, Brazil, which is an important region for cattle production located in the Amazon region. A total of 3466 adult female cattle from 176 herds were tested, leading to a frequency of seropositive animals of 14.7%, 3.7% and 65.5% and a herd positivity of 87.4%, 41.3% and 98.8% for infections caused by Neospora spp., B. abortus and Leptospira spp., respectively. The five most frequently diagnosed serologic responses to Leptospira spp. were those against serovars hardjo, wolfii, grippotyphosa, hebdomadis and shermani. The following associations were found: practice of artificial insemination, large farm size, large herd size, large number of dogs and high number of total abortions per year with the presence of antibodies against serovar hardjo; positive results to serovar grippotyphosa with the presence of dogs; inappropriate disposal of aborted foetuses with positivity to serovar hebdomadis. Serovar grippotyphosa was also associated with number of episodes of abortions. Neospora spp. positive herds were associated with episodes of abortion and B. abortus infection with the disposal of dead animals and aborted foetuses on pastures and with the use of artificial insemination. In conclusion, the high frequency of brucellosis, leptospirosis and neosporosis in the region may be a consequence of social, natural and raising conditions as: (i) climate conditions that favour the survival and spread of pathogens in the environment; (ii) farms located in regions bordering forest areas; (iii) farms in areas of difficult access to the veterinary service; (iv) extensive beef herds raised at pastures with different age and productive groups inter-mingled; and (v) minimal concerns regarding hygiene practices and disease prevention measures. © 2013 Blackwell Verlag GmbH.

  8. Toxoplasma gondii, Neospora caninum and tick-transmitted bacterium Anaplasma phagocytophilum infections in one selected goat farm in Slovakia.

    Science.gov (United States)

    Čobádiová, Andrea; Reiterová, Katarina; Derdáková, Markéta; Špilovská, Silvia; Turčeková, Ludmila; Hviščová, Ivana; Hisira, Vladimir

    2013-12-01

    Parasitic diseases of livestock together with poor welfare conditions can negatively affect the health status and production of small ruminants. Protozoan parasites and tick-borne infectious agents are common threat of livestock including small ruminants mostly during the pasture season. Therefore the priority of the study was to analyse the circulation and presence of two protozoan parasites Toxoplasma gondii and Neospora caninum as well as tick-transmitted bacterium Anaplasma phagocytophilum in one selected goat farm in Eastern Slovakia. Throughout a three-year study period we have repeatedly screened the sera and blood of goats and dogs from monitored farm. In total, 343 blood serum samples from 116 goats were examined by ELISA. The mean seropositivity for T. gondii was 56.9% (66/116, CI (95%) = 48-66.0) and 15.5% (18/116, CI (95%) = 9.3-22.7) for N. caninum. The permanent occurrence of anti-Toxoplasma and anti-Neospora antibodies was detected in repeatedly examined goats during the whole monitored period. The presence of both parasites in the flock was analysed by PCR. DNA of T. gondii was confirmed in 12 out of 25 Toxoplasma-seropositive goats and N. caninum in 14 samples out of 18 Neospora-seropositive animals; four goats were co-infected with both pathogens. The risk of endogenous transmission of both parasites was pursued by examination of 41 kid's sera, where seropositivity for toxoplasmosis was 31.7% and for neosporosis 14.6%. In dogs 61.1% seropositivity for T. gondii and 38.9% for N. caninum was found, however, their faeces were negative for coccidian oocysts. Eight out of 108 tested animals were infected with A. phagocytophilum, the causative agent of tick-borne fever. Seven of them were simultaneously infected with T. gondii and A. phagocytophilum, out of which four goats were concurrently infected with all three pathogens.

  9. Occurrence and first multilocus microsatellite genotyping of Neospora caninum from naturally infected dogs in dairy farms in Henan, Central China.

    Science.gov (United States)

    Qian, Weifeng; Wang, Tianqi; Yan, Wenchao; Han, Lifang; Zhai, Kai; Duan, Baoqing; Lv, Chaochao

    2016-08-01

    Neospora caninum is one of the important causes of abortion in dairy cattle worldwide. The dog is known as a definitive host of N. caninum and can transmit the parasite to cattle by shedding oocysts. The aim of the present study is to detect the presence of N. caninum in feces of dairy farm dogs and determine the genetic characteristics of N. caninum in Central China. A total of 78 fecal samples were collected from dogs in dairy farms from May to November 2014 and examined by microscopy and nested PCR based on Nc5 gene. Neospora-like oocysts were microscopically detected in two fecal samples, of which only one (Nc-LY1) was confirmed to be N. caninum by nested PCR. Seven out of 78 fecal samples (9.0 %) were N. caninum DNA positive, of which Neospora-like oocysts were simultaneously microscopically detected only in one sample (Nc-LY1). No statistical associations were found between the positive rates and age or sex of dogs (P > 0.05). The N. caninum-positive DNA samples were further analyzed by multilocus microsatellite (MS) genotyping for MS4, MS5, MS6A, MS7, MS8, MS10, MS12, and Cont-14. Only the fecal sample in which oocysts were detected was successfully genotyped at all genetic loci, and a new genotype was identified. To our knowledge, this study is the first report of genetic characterization of N. caninum isolates from naturally infected dogs based on multilocus microsatellites in China.

  10. Comparative Genomics of the Apicomplexan Parasites Toxoplasma gondii and Neospora caninum: Coccidia Differing in Host Range and Transmission Strategy

    Science.gov (United States)

    Reid, Adam James; Vermont, Sarah J.; Cotton, James A.; Harris, David; Hill-Cawthorne, Grant A.; Könen-Waisman, Stephanie; Latham, Sophia M.; Mourier, Tobias; Norton, Rebecca; Quail, Michael A.; Sanders, Mandy; Shanmugam, Dhanasekaran; Sohal, Amandeep; Wasmuth, James D.; Brunk, Brian; Grigg, Michael E.; Howard, Jonathan C.; Parkinson, John; Roos, David S.; Trees, Alexander J.; Berriman, Matthew; Pain, Arnab; Wastling, Jonathan M.

    2012-01-01

    Toxoplasma gondii is a zoonotic protozoan parasite which infects nearly one third of the human population and is found in an extraordinary range of vertebrate hosts. Its epidemiology depends heavily on horizontal transmission, especially between rodents and its definitive host, the cat. Neospora caninum is a recently discovered close relative of Toxoplasma, whose definitive host is the dog. Both species are tissue-dwelling Coccidia and members of the phylum Apicomplexa; they share many common features, but Neospora neither infects humans nor shares the same wide host range as Toxoplasma, rather it shows a striking preference for highly efficient vertical transmission in cattle. These species therefore provide a remarkable opportunity to investigate mechanisms of host restriction, transmission strategies, virulence and zoonotic potential. We sequenced the genome of N. caninum and transcriptomes of the invasive stage of both species, undertaking an extensive comparative genomics and transcriptomics analysis. We estimate that these organisms diverged from their common ancestor around 28 million years ago and find that both genomes and gene expression are remarkably conserved. However, in N. caninum we identified an unexpected expansion of surface antigen gene families and the divergence of secreted virulence factors, including rhoptry kinases. Specifically we show that the rhoptry kinase ROP18 is pseudogenised in N. caninum and that, as a possible consequence, Neospora is unable to phosphorylate host immunity-related GTPases, as Toxoplasma does. This defense strategy is thought to be key to virulence in Toxoplasma. We conclude that the ecological niches occupied by these species are influenced by a relatively small number of gene products which operate at the host-parasite interface and that the dominance of vertical transmission in N. caninum may be associated with the evolution of reduced virulence in this species. PMID:22457617

  11. Comparative genomics of the apicomplexan parasites Toxoplasma gondii and Neospora caninum: Coccidia differing in host range and transmission strategy.

    Directory of Open Access Journals (Sweden)

    Adam James Reid

    Full Text Available Toxoplasma gondii is a zoonotic protozoan parasite which infects nearly one third of the human population and is found in an extraordinary range of vertebrate hosts. Its epidemiology depends heavily on horizontal transmission, especially between rodents and its definitive host, the cat. Neospora caninum is a recently discovered close relative of Toxoplasma, whose definitive host is the dog. Both species are tissue-dwelling Coccidia and members of the phylum Apicomplexa; they share many common features, but Neospora neither infects humans nor shares the same wide host range as Toxoplasma, rather it shows a striking preference for highly efficient vertical transmission in cattle. These species therefore provide a remarkable opportunity to investigate mechanisms of host restriction, transmission strategies, virulence and zoonotic potential. We sequenced the genome of N. caninum and transcriptomes of the invasive stage of both species, undertaking an extensive comparative genomics and transcriptomics analysis. We estimate that these organisms diverged from their common ancestor around 28 million years ago and find that both genomes and gene expression are remarkably conserved. However, in N. caninum we identified an unexpected expansion of surface antigen gene families and the divergence of secreted virulence factors, including rhoptry kinases. Specifically we show that the rhoptry kinase ROP18 is pseudogenised in N. caninum and that, as a possible consequence, Neospora is unable to phosphorylate host immunity-related GTPases, as Toxoplasma does. This defense strategy is thought to be key to virulence in Toxoplasma. We conclude that the ecological niches occupied by these species are influenced by a relatively small number of gene products which operate at the host-parasite interface and that the dominance of vertical transmission in N. caninum may be associated with the evolution of reduced virulence in this species.

  12. Plasmodium simium/Plasmodium vivax infections in southern brown howler monkeys from the Atlantic Forest

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    Daniela Camargos Costa

    2014-08-01

    Full Text Available Blood infection by the simian parasite, Plasmodium simium, was identified in captive (n = 45, 4.4% and in wild Alouatta clamitans monkeys (n = 20, 35% from the Atlantic Forest of southern Brazil. A single malaria infection was symptomatic and the monkey presented clinical and haematological alterations. A high frequency of Plasmodium vivax-specific antibodies was detected among these monkeys, with 87% of the monkeys testing positive against P. vivax antigens. These findings highlight the possibility of malaria as a zoonosis in the remaining Atlantic Forest and its impact on the epidemiology of the disease.

  13. FIRST REPORT OF CUTANEOUS LEISHMANIASIS CAUSED BY Leishmania (Leishmania infantum chagasi IN AN URBAN AREA OF RIO DE JANEIRO, BRAZIL

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    Marcelo Rosandiski LYRA

    2015-10-01

    Full Text Available SUMMARY American tegumentary leishmaniasis (ATL is an infectious disease caused by protozoa of the genus Leishmania, and transmitted by sandflies. In the state of Rio de Janeiro, almost all of the cases of American tegumentary leishmaniasis (ATL are caused by Leishmania (Viannia braziliensis, while cases of visceral leishmaniasis (VL are caused by Leishmania (Leishmania infantum chagasi. The resurgence of autochthonous VL cases in Rio de Janeiro is related to the geographic expansion of the vector Lutzomyia longipalpis and its ability to adapt to urban areas. We report the first case of leishmaniasis with exclusively cutaneous manifestations caused by L. (L. infantum chagasi in an urban area of Rio de Janeiro. An eighty-one-year-old woman presented three pleomorphic skin lesions that were not associated with systemic symptoms or visceromegalies. Multilocus enzyme electrophoresis identified L. (L. infantum chagasi, but direct smear and PCR of bone narrow were negative for Leishmania sp. (suggesting exclusively cutaneous involvement. We discuss the different dermatological presentations of viscerotropic leishmaniasis of the New and Old World, and the clinical and epidemiological importance of the case. Etiologic diagnosis of ATL based upon exclusive clinical criteria may lead to incorrect conclusions. We should be aware of the constant changes in epidemiological patterns related to leishmaniases.

  14. FIRST REPORT OF CUTANEOUS LEISHMANIASIS CAUSED BY Leishmania (Leishmania) infantum chagasi IN AN URBAN AREA OF RIO DE JANEIRO, BRAZIL.

    Science.gov (United States)

    Lyra, Marcelo Rosandiski; Pimentel, Maria Inês Fernandes; Madeira, Maria de Fátima; Antonio, Liliane de Fátima; Lyra, Janine Pontes de Miranda; Fagundes, Aline; Schubach, Armando de Oliveira

    2015-01-01

    American tegumentary leishmaniasis (ATL) is an infectious disease caused by protozoa of the genus Leishmania, and transmitted by sandflies. In the state of Rio de Janeiro, almost all of the cases of American tegumentary leishmaniasis (ATL) are caused by Leishmania (Viannia) braziliensis, while cases of visceral leishmaniasis (VL) are caused by Leishmania (Leishmania) infantum chagasi. The resurgence of autochthonous VL cases in Rio de Janeiro is related to the geographic expansion of the vector Lutzomyia longipalpis and its ability to adapt to urban areas. We report the first case of leishmaniasis with exclusively cutaneous manifestations caused by L. (L.) infantum chagasi in an urban area of Rio de Janeiro. An eighty-one-year-old woman presented three pleomorphic skin lesions that were not associated with systemic symptoms or visceromegalies. Multilocus enzyme electrophoresis identified L. (L.) infantum chagasi, but direct smear and PCR of bone narrow were negative for Leishmania sp. (suggesting exclusively cutaneous involvement). We discuss the different dermatological presentations of viscerotropic leishmaniasis of the New and Old World, and the clinical and epidemiological importance of the case. Etiologic diagnosis of ATL based upon exclusive clinical criteria may lead to incorrect conclusions. We should be aware of the constant changes in epidemiological patterns related to leishmaniases.

  15. Rattus norvegicus (Rodentia: Muridae Infected by Leishmania (Leishmania infantum (syn. Le. chagasi in Brazil

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    Fabiana de Oliveira Lara-Silva

    2014-01-01

    Full Text Available In the present study we surveyed the fauna of phlebotomine sand flies and small mammals in peridomestic areas from a Brazilian municipality where the American cutaneous leishmaniasis (ACL is endemic. A total of 608 female phlebotomine sand flies were captured during nine months in 2009 and 2010. Seven different species were represented with 60% of them being Lutzomyia intermedia and Lu. whitmani, both incriminated vectors of ACL. Lu. longipalpis, a proven vector of visceral leishmaniasis (VL was also captured at high proportion (12.8%. Genomic DNA analysis of 136 species-specific pools of female sand flies followed by molecular genotyping showed the presence of Leishmania infantum DNA in two pools of Lu. longipalpis. The same Leishmania species was found in one blood sample from Rattus norvegicus among 119 blood and tissue samples analysed. This is the first report of Le. infantum in R. norvegicus in the Americas and suggests a possible role for this rodent species in the zoonotic cycle of VL. Our study coincided with the reemergence of VL in Governador Valadares.

  16. Seasonal transmission of Leishmania (Leishmania mexicana in the state of Campeche, Yucatan Peninsula, Mexico

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    Andrade-Narvaez Fernando J

    2003-01-01

    Full Text Available In the Yucatan Peninsula, Mexico, localized cutaneous leishmaniasis (LCL caused by Leishmania (Leishmania mexicana is a typical wild zoonosis restricted to the forest, and humans are only accidentally involved. The transmission of L. (L. mexicana has been related to the patient's occupation: "chicleros"(gum collectors and agricultural workers. The objective of this study was to document L. (L. mexicana seasonally of transmission in endemic areas of LCL in the state of Campeche, Yucatan Peninsula, Mexico. The timing of incidence of LCL in humans during 1993-1994, as well as the rate and time of infection in rodents and sand flies between February 1993 and March 1995 were analyzed. Rodents and sand flies were found infected between November and March, when men carried out their field activities and are exposed. Based on results analyzed, it is concluded that L. (L. mexicana in the endemic area of LCL in the state of Campeche, Yucatan Peninsula, Mexico, presents a seasonal transmission restricted to the months of November to March. The knowledge of the timing of the transmission cycle in an endemic area of leishmaniasis is very important because intervention measures on the high-risk focus and population might be restricted.

  17. Chronic interstitial pneumonitis in dogs naturally infected with Leishmania (Leishmania chagasi: a histopathological and morphometric study

    Directory of Open Access Journals (Sweden)

    Gonçalves Ricardo

    2003-01-01

    Full Text Available Eighteen mongrel dogs of unknown age and naturally infected with Leishmania (Leishmania chagasi, were obtained from the City Hall of Belo Horizonte, Brazil. Four dogs were used as control. Lung samples were obtained and immediately fixed in formalin. The histopathological picture of all lung tissue sections was a chronic and diffuse interstitial pneumonitis. The thickened inter-alveolar septa were characterized by the cellular exudate (mostly macrophages, lymphocytes and plasmocytes associated with collagen deposition. Morphometric analysis showed greater septal thickness in the infected animals than in controls. In fact, the morphometric study of collagen stained with ammoniac silver confirmed a larger deposition of collagen in the infected animals. The parasitologic method was carried out during the study of the lesions on the slides. However, we did not observe any correlation between the histopathologic and morphometric data and the clinical status of the animals. We conclude that the pulmonary lesions observed in all naturally infected dogs were correlated with the disease and that the morphometric method used was satisfactory for the analysis of septal thickness and of increased collagen deposition, confirming the presence of fibrosis.

  18. Chronic interstitial pneumonitis in dogs naturally infected with Leishmania (Leishmania) chagasi: a histopathological and morphometric study.

    Science.gov (United States)

    Gonçalves, Ricardo; Tafuri, Washington Luiz; Melo, Maria Norma de; Raso, Pedro; Tafuri, Wagner Luiz

    2003-01-01

    Eighteen mongrel dogs of unknown age and naturally infected with Leishmania (Leishmania) chagasi, were obtained from the City Hall of Belo Horizonte, Brazil. Four dogs were used as control. Lung samples were obtained and immediately fixed in formalin. The histopathological picture of all lung tissue sections was a chronic and diffuse interstitial pneumonitis. The thickened inter-alveolar septa were characterized by the cellular exudate (mostly macrophages, lymphocytes and plasmocytes) associated with collagen deposition. Morphometric analysis showed greater septal thickness in the infected animals than in controls. In fact, the morphometric study of collagen stained with ammoniac silver confirmed a larger deposition of collagen in the infected animals. The parasitologic method was carried out during the study of the lesions on the slides. However, we did not observe any correlation between the histopathologic and morphometric data and the clinical status of the animals. We conclude that the pulmonary lesions observed in all naturally infected dogs were correlated with the disease and that the morphometric method used was satisfactory for the analysis of septal thickness and of increased collagen deposition, confirming the presence of fibrosis.

  19. [Western blot, ELISA and indirect immunofluorescence test evaluation of Leishmania (Leishmania) infantum-infected dogs].

    Science.gov (United States)

    Vargas-Duarte, Jimmy J; López-Páez, Myriam C; Escovar-Castro, Jesús E; Fernández-Manrique, José

    2009-08-01

    Evaluating canine visceral leishmaniasis diagnostic test performance in Colombia and adapting the Western blot test in naturally and experimentally infected dogs. Sera were obtained from 10 experimentally L. Infantum-infected dogs, 5 naturally infected dogs, 16 healthy dogs, 26 Babesia canis, Erhlichia canis, Dirofilaria immitis, Trypanosoma cruzi and Leishmania (Viannia) spp infected dogs, 40 dogs from non-endemic areas and 150 from endemic areas. Sera were tested for L. infantum infection using immunofluorescent antibody (IFAT), ELISA and Western blot (WB) tests. Positives results were obtained for 73 % of known infected dogs by the IFAT test and false positives were obtained for 2.5 % of non-infected dogs using WB. ELISA was not efficient for diagnosis. 24 antigenic fractions were recognised in tested sera using WB; however, 29, 34, 50, 69, 75, 86, 99 and 123 kDa bands were recognised in sera from dogs from non-endemic areas, healthy dogs and Trypanosoma cruzi, Erhlichia canis, Dirofilaria immitis and Babesia canis infected dogs. The 13 kDa fraction proved potentially useful for diagnosing canine visceral leishmaniasis. The separate use of parasitological and serological test could lead to misdiagnosis of Leishmania infection; using both kinds of technique simultaneously is thus highly recommended.

  20. Curcumin overcomes the inhibitory effect of nitric oxide on Leishmania.

    Science.gov (United States)

    Chan, Marion Man-Ying; Adapala, Naga Suresh; Fong, Dunne

    2005-04-01

    Upon Leishmania infection, macrophages are activated to produce nitrogen and oxygen radicals simultaneously. It is well established that the infected host cells rely on nitric oxide (NO) as the major weapon against the intracellular parasite. In India where leishmaniasis is endemic, the spice turmeric is used prolifically in food and for insect bites. Curcumin, the active principle of turmeric, is a scavenger of NO. This report shows that curcumin protects promastigotes and amastigotes of the visceral species, Leishmania donovani, and promastigotes of the cutaneous species, L. major, against the actions of S-nitroso-N-acetyl-D,L-penicillamine (SNAP) and DETANONOate, which release NO, 3-morpholino-sydnonimine hydrochloride (SIN-1), which releases NO and superoxide, and peroxynitrite, which is formed from the reaction of NO with superoxide. Thus, curcumin, as an antioxidant, is capable of blocking the action of both NO and NO congeners on the Leishmania parasite.

  1. What has proteomics taught us about Leishmania development?

    Science.gov (United States)

    Tsigankov, Polina; Gherardini, Pier Federico; Helmer-Citterich, Manuela; Zilberstein, Dan

    2012-08-01

    Leishmania are obligatory intracellular parasitic protozoa that cycle between sand fly mid-gut and phagolysosomes of mammalian macrophages. They have developed genetically programmed changes in gene and protein expression that enable rapid optimization of cell function according to vector and host environments. During the last two decades, host-free systems that mimic intra-lysosomal environments have been devised in which promastigotes differentiate into amastigotes axenically. These cultures have facilitated detailed investigation of the molecular mechanisms underlying Leishmania development inside its host. Axenic promastigotes and amastigotes have been subjected to transcriptome and proteomic analyses. Development had appeared somewhat variable but was revealed by proteomics to be strictly coordinated and regulated. Here we summarize the current understanding of Leishmania promastigote to amastigote differentiation, highlighting the data generated by proteomics.

  2. Subversion of host cell signalling by the protozoan parasite Leishmania.

    Science.gov (United States)

    Gregory, D J; Olivier, M

    2005-01-01

    The protozoa Leishmania spp. are obligate intracellular parasites that inhabit the macrophages of their host. Since macrophages are specialized for the identification and destruction of invading pathogens, both directly and by triggering an innate immune response, Leishmania have evolved a number of mechanisms for suppressing some critical macrophage activities. In this review, we discuss how various species of Leishmania distort the host macrophage's own signalling pathways to repress the expression of various cytokines and microbicidal molecules (nitric oxide and reactive oxygen species), and antigen presentation. In particular, we describe how MAP Kinase and JAK/STAT cascades are repressed, and intracellular Ca2+ and the activities of protein tyrosine phosphatases, in particular SHP-1, are elevated.

  3. Molecular crosstalks in Leishmania-sandfly-host relationships

    Directory of Open Access Journals (Sweden)

    Volf P.

    2008-09-01

    Full Text Available Sandflies (Diptera: Phlebotominae are vectors of Leishmania parasites, causative agents of important human and animal diseases with diverse manifestations. This review summarizes present knowledge about the vectorial part of Leishmania life cycle and parasite transmission to the vertebrate host. Particularly, it focuses on molecules that determine the establishment of parasite infection in sandfly midgut. It describes the concept of specific versus permissive sandfly vectors, explains the epidemiological consequences of broad susceptibility of permissive sandflies and demonstrates that genetic exchange may positively affect Leishmania fitness in the vector. Last but not least, the review describes recent knowledge about circulating antibodies produced by hosts in response to sandfly bites. Studies on specificity and kinetics of antibody response revealed that anti-saliva IgG could be used as a marker of host exposure to sandflies, i.e. as a useful tool for evaluation of vector control.

  4. Leishmania (infantum chagasi in canine urinary sediment

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    Ivete Lopes de Mendonça

    Full Text Available Canine visceral leishmaniasis (CVL is difficult to diagnosis, mainly due to the presence of asymptomatic animals, the diversity of clinical symptoms and the difficulty in obtaining diagnostic evidence of high sensitivity and specificity. The purpose of this study was to diagnose CVL in urinary sediment of 70 dogs of different breeds, sexes and ages from the veterinary hospital of the Federal University of Piauí and Zoonosis Control Center of Teresina, Brazil. The serological tests were TR DPP® for CVL and enzyme-linked immunosorbent assay (ELISA for CVL, parasitological exams of bone marrow and lymph nodes and urine sediment cultures. Leishmania was detected in the bone marrow and/or lymph node of 61.0% of the animals (43/70, and urine sediment culture was positive in 9.30% (4/43 of these animals. In the serological exams, 70.0% (49/70 were reactive using the DPP and 78.2% (55/70 were reactive using ELISA. The goal of this study was to diagnose the presence of L. (infantum chagasi in a culture of urinary sediment.

  5. Leishmania (L. mexicana infected bats in Mexico: novel potential reservoirs.

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    Miriam Berzunza-Cruz

    2015-01-01

    Full Text Available Leishmania (Leishmania mexicana causes cutaneous leishmaniasis, an endemic zoonosis affecting a growing number of patients in the southeastern states of Mexico. Some foci are found in shade-grown cocoa and coffee plantations, or near perennial forests that provide rich breeding grounds for the sand fly vectors, but also harbor a variety of bat species that live off the abundant fruits provided by these shade-giving trees. The close proximity between sand flies and bats makes their interaction feasible, yet bats infected with Leishmania (L. mexicana have not been reported. Here we analyzed 420 bats from six states of Mexico that had reported patients with leishmaniasis. Tissues of bats, including skin, heart, liver and/or spleen were screened by PCR for Leishmania (L. mexicana DNA. We found that 41 bats (9.77%, belonging to 13 species, showed positive PCR results in various tissues. The infected tissues showed no evidence of macroscopic lesions. Of the infected bats, 12 species were frugivorous, insectivorous or nectarivorous, and only one species was sanguivorous (Desmodus rotundus, and most of them belonged to the family Phyllostomidae. The eco-region where most of the infected bats were caught is the Gulf Coastal Plain of Chiapas and Tabasco. Through experimental infections of two Tadarida brasiliensis bats in captivity, we show that this species can harbor viable, infective Leishmania (L. mexicana parasites that are capable of infecting BALB/c mice. We conclude that various species of bats belonging to the family Phyllostomidae are possible reservoir hosts for Leishmania (L. mexicana, if it can be shown that such bats are infective for the sand fly vector. Further studies are needed to determine how these bats become infected, how long the parasite remains viable inside these potential hosts and whether they are infective to sand flies to fully evaluate their impact on disease epidemiology.

  6. Cross-sectional survey in pig breeding farms in Hesse, Germany: seroprevalence and risk factors of infections with Toxoplasma gondii, Sarcocystis spp. and Neospora caninum in sows

    DEFF Research Database (Denmark)

    Damriyasa, I.M.; Bauer, C.; Edelhofer, R.

    2004-01-01

    A cross-sectional survey was performed to estimate the prevalences of antibodies to Toxoplasma gondii (ELISA, IFAT), Sarcocystis spp. (ELISA, using S. miescheriana as antigen) and Neospora caninum (ELISA, immunoblotting) in sows from breeding farms in southern Hesse, Germany. A total of 2041 plas...... and the confirmatory immunoblotting technique. This may indicate the first natural N. caninum infection in pigs....

  7. Comparative genomics of the Apicomplexan parasites Toxoplasma gondii and Neospora caninum 

    DEFF Research Database (Denmark)

    Reid, Adam James; Vermont, Sarah J.; Cotton, James A.

    2012-01-01

    Coccidian parasites have a major impact on human and animal health world-wide and are among the most successful and widespread parasitic protozoa. They include Neospora caninum which is a leading cause of abortion in cattle and one of its nearest relatives, Toxoplasma gondii. Despite its close ph...

  8. Coprodiagnosis of Hammondia heydorni in dogs by PCR based on ITS 1 rRNA: differentiation from morphologically indistinguishable oocysts of Neospora caninum

    Czech Academy of Sciences Publication Activity Database

    Šlapeta, Jan Roger; Koudela, Břetislav; Votýpka, Jan; Modrý, David; Hořejš, R.; Lukeš, Julius

    2002-01-01

    Roč. 163, č. 2 (2002), s. 147-154 ISSN 1090-0233 R&D Projects: GA AV ČR IAA6022903 Institutional research plan: CEZ:AV0Z6022909 Keywords : Hammondia heydorni * Neospora caninum * coprodiagnosis Subject RIV: EG - Zoology Impact factor: 1.289, year: 2002

  9. Cytokine gene expression at the materno-foetal interface after experimental Neospora caninum infection of heifers at 110 days of gestation

    Science.gov (United States)

    Neospora caninum is a major cause of abortion in cattle but the reasons why some animals abort and not others remain unclear. The immunological control of the parasite in the placenta or by the foetus could be the key to determining the mechanism of abortion and/or transplacental transmission to the...

  10. Seroprevalence of Neospora caninum and Toxoplasma gondii antibodies in white tailed deer (odocoileus virginianus) from Iowa and Minnesota using four serologic tests

    Science.gov (United States)

    The white-tailed deer (Odocoileus virginianus) is considered one of the most important wildlife reservoir of Neospora caninum and Toxoplasma gondii in the US. Sera from white-tailed deer from Minnesota and Iowa were tested for antibodies to N. caninum by four serologic tests including the indi...

  11. Neospora caninum tachyzoite- and antigen-stimulated production of cytokines by enriched bone marrow-derived dendritic cells and spleen cells of naive BALB/c mice

    Science.gov (United States)

    Neospora caninum is an intracellular protozoan pathogen, causing abortion in cattle. This parasite elicits a typical type 1 immune response in host animals and it is widely believed that the strong type 1 immune response during pregnancy may result in fetal death. Pro-inflammatory and/or inflammator...

  12. Maternal and fetal immune response patterns in heifers experimentally infected with Neospora caninum in the second trimester of pregnancy- A descriptive study

    Science.gov (United States)

    Fetal and maternal immune responses 3, 6 and 9 weeks post infection (wpi) were investigated in cows experimentally infected with Neospora caninum on day 110 of gestation. Descriptive analysis showed that the fetuses had lower percentages of spleen T cell subpopulations (CD3+, CD4+ and CD8+) at 6 wpi...

  13. Effect of a killed whole Neospora caninum tachyzoite vaccine on the crube abortion rate of Costa Rican dairy cows under field conditions

    NARCIS (Netherlands)

    Romero, J.J.; Perez, E.; Frankena, K.

    2004-01-01

    A standard field trial was carried out to assess the effect of a commercial Neospora-vaccine based on whole killed tachyzoites (Bovilis–Neoguard, Intervet®) on the abortion rate. Eight hundred and seventy-six cows, over 2.5 months pregnant, belonging to 25 Costa Rican dairy herds, were used in the

  14. Low prevalence of Neospora caninum and Toxoplasma gondii antibodies in dogs in Jilin, Henan and Anhui Provinces of the People’s Republic of China

    Science.gov (United States)

    Background: Neospora caninum and Toxoplasma gondii are important pathogens of worldwide distribution. N. caninum is a major cause of abortion in cattle and dogs are main reservoirs because they excrete the environmentally resistant oocysts. Toxoplasmosis is a worldwide zoonosis and dogs are consider...

  15. Unravelling the Neospora caninum secretome through the secreted fraction (ESA) and quantification of the discharged tachyzoite using high-resolution mass spectrometry-based proteomics

    NARCIS (Netherlands)

    Pollo-Oliveira, L.; Post, H.; Acencio, M.L.; Lemke, N.; van den Toorn, H.W.P.; Tragante Do O, V.; Heck, A.J.R.; Altelaar, A.F.M.; Yatsuda, A.P.

    2013-01-01

    Background The apicomplexan parasite Neospora caninum causes neosporosis, a disease that leads to abortion or stillbirth in cattle, generating an economic impact on the dairy and beef cattle trade. As an obligatory intracellular parasite, N. caninum needs to invade the host cell in an active manner

  16. Artemisinin resistance marker of Plasmodium falciparum in Osogbo ...

    African Journals Online (AJOL)

    Artemisinin derivatives constitute a key component of the present-day treatment for Plasmodium falciparum malaria. Resistance with artemisinins is generally associated with S769N point mutation in the sarco-endoplasmic reticulumdependant ATPase6 (SERCA ATPase6) gene of Plasmodium falciparum, few studies have ...

  17. Population genomics diversity of Plasmodium falciparum in malaria ...

    African Journals Online (AJOL)

    Infectious Diseases and Environmental Health Research Group, Department of ... Conclusion: There is high genetic diversity in MSP – 2 and GLURP allelic families of Plasmodium falciparum isolates from Okelele. Health Centre, Ilorin, Nigeria. Keywords: Plasmodium falciparum, Merozoite Surface Protein, genetic diversity.

  18. Population genomics diversity of Plasmodium falciparum in malaria ...

    African Journals Online (AJOL)

    Background: Plasmodium falciparum, the most dangerous malaria parasite species to humans remains an important public health concern in Okelele, a rural community in Ilorin, Kwara State, Nigeria. There is however little information about the genetic diversity of Plasmodium falciparum in Nigeria. Objective: To determine ...

  19. Further support for a palaearctic origin of Leishmania

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    Sara F Kerr

    2000-08-01

    Full Text Available The fossil record and systematics of murid rodents, reservoirs of zoonotic cutaneous leishmaniasis in the Palaearctic, Oriental, African, Nearctic and Neotropical, strongly support a Palaearctic origin of Leishmania. The fossil record and systematics of phlebotomine sand flies reinforce this idea. Interpretations of molecular data that place the origin of Leishmania in the Neotropical are inconsistent with the natural histories of reservoirs and vectors. The evolutionary pattern of New World rats (Sigmodontinae indicates that they may be the most important reservoirs of zoonotic cutaneous leishmaniasis throughout their range.

  20. CD8+ T cells in Leishmania infections: friends or foes?

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    Simona eStager

    2012-01-01

    Full Text Available Host protection against several intracellular pathogens requires the induction of CD8+ T cell responses. CD8+ T cells are potent effector cells that can produce high amounts of pro-inflammatory cytokines and kill infected target cells efficiently. However, a protective role for CD8+ T cells during Leishmania infections is still controversial and largely depends on the infection model. In this review, we discuss the role of CD8+ T cells during various types Leishmania infections, following vaccination, and as potential immunotherapeutic targets.

  1. The past, present, and future of Leishmania genomics and transcriptomics

    Science.gov (United States)

    Cantacessi, Cinzia; Dantas-Torres, Filipe; Nolan, Matthew J.; Otranto, Domenico

    2015-01-01

    It has been nearly 10 years since the completion of the first entire genome sequence of a Leishmania parasite. Genomic and transcriptomic analyses have advanced our understanding of the biology of Leishmania, and shed new light on the complex interactions occurring within the parasite–host–vector triangle. Here, we review these advances and examine potential avenues for translation of these discoveries into treatment and control programs. In addition, we argue for a strong need to explore how disease in dogs relates to that in humans, and how an improved understanding in line with the ‘One Health’ concept may open new avenues for the control of these devastating diseases. PMID:25638444

  2. Serological survey of Neospora caninum in small ruminants from Pernambuco State, Brazil Inquérito sorológico de Neospora caninum em pequenos ruminantes do estado de Pernambuco, Brasil

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    Antonio Amélia Santos Mucalane Tembue

    2011-09-01

    Full Text Available Neospora caninum infection is an important cause of bovine abortion as well as neonatal mortality in goats and sheep. A serological survey for antibodies against N. caninum in goats and sheep was carried out in the municipality of Ibimirim, PE, Northeastern Brazil. The imunnofluoresce antibody test showed that 26.6% (85/319 of the goats and 64.2% (52/81 of the sheep were positive. Serologic reactivity was associated with age in goats (p 0.05, with increasing rates in older animals. These results indicate exposure to N. caninum among small ruminants in the study area.A infecção por Neospora caninum é uma importante causa de abortos em bovinos, assim como mortalidade neonatal em caprinos e ovinos. Uma pesquisa sorológica de anticorpos anti-N. caninum foi realizada no município de Ibimirim (PE, Brasil. Os resultados ao teste de imunofluorescência revelaram que 26,6% (85/319 dos caprinos e 64,2% (52/81 dos ovinos foram positivos. A reatividade à sorologia foi associada com a idade nos caprinos (p 0,05, com maior ocorrência nos animais mais velhos. Estes resultados indicam exposição a N. caninum entre pequenos ruminantes na área estudada.

  3. Neosporose equina: ocorrência de anticorpos anti-Neospora spp. e associação entre status sorológico de éguas e de suas crias Equine neosporosis: occurrence of antibodies against Neospora spp. and association between the serological status of the mares and of their offspring

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    Gustavo Toscan

    2010-08-01

    Full Text Available Os protozoários Neospora caninum e N. hughesi infectam os equinos e podem provocar diferentes sinais clínicos associados a problemas reprodutivos ou a distúrbios neurológicos, respectivamente. A patogenia da neosporose é pouco conhecida nos equinos, bem como as fontes de infecção horizontal de N. hughesi. Além disso, há dúvidas quanto ao papel da transmissão vertical de Neospora spp. na sua manutenção em populações equinas. Neste estudo avaliaram-se: (1 a ocorrência da infecção por Neospora spp. na população de éguas em idade reprodutiva em um haras de cavalos da raça Crioula; e (2 a possível associação entre o status sorológico destas éguas com o de suas crias, como meio de investigar, indiretamente, a relevância da transmissão transplacentária na ocorrência da infecção por Neospora spp. nestes animais. A associação entre o status sorológico das éguas e o de suas crias foi altamente significativa. Os animais descendentes de éguas soropositivas tiveram maior ocorrência de anticorpos anti-Neospora spp. do que os descendentes de éguas soronegativas, embora expostos aos mesmos fatores de risco ambientais. A associação entre parentesco em primeiro grau e status sorológico indica a influência da infecção vertical (transplacentária na ocorrência de Neospora spp. na população equina estudada.Neospora caninum and N. hughesi are protozoa which can infect horses and can cause reproductive and neurological diseases, respectively. The pathogenesis of neosporosis in horses is poorly understood, as well as the sources of horizontal infection of N. hughesi. Furthermore, there are doubts about the role of the vertical transmission of Neospora spp. in maintenance of these parasites in equine populations. In this study, we evaluated: (1 the occurrence of infections by Neospora spp. in a population of mares (in reproductive age on a farm of Crioula breed horses; and (2 the possible association between the

  4. Neospora caninum in dairy cattle in Paraná State, Brazil: histological and immunohistochemical analys is in fetuses/ Neospora caninum em vacas leiteiras no Estado do Paraná, Brasil: análise histológica e imuno-histoquímica em fetos

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    Ana Paula Frederico Rodrigues Loureiro Bracarense

    2005-06-01

    Full Text Available Thirty-four bovine abortions (fetuses from Paraná State were examined histologically and immunohistochemically. Eight fetuses had non-suppurative encephalitis and miocarditis, and Neospora caninum were detected by immunohistochemistry. Four cows were seropositive to N. caninum. It was the first detection of congenital neosporosis in aborted bovines fetuses, in Paraná State, Brazil.Trinta e quatro fetos bovinos abortados, no Estado do Paraná, foram examinados através de análise histológica e imuno-histoquímica. O Neospora caninum foi detectado, pela imuno-histoquímica, em oito fetos que apresentavam miocardite e encefalite não supurativa. Quatro vacas foram soropositivas para o Neospora caninum. Este é o primeiro relato de neosporose congênita em fetos bovinos abortados, no Estado do Paraná, Brasil.

  5. Mitosis in the Human Malaria Parasite Plasmodium falciparum ▿

    Science.gov (United States)

    Gerald, Noel; Mahajan, Babita; Kumar, Sanjai

    2011-01-01

    Malaria is caused by intraerythrocytic protozoan parasites belonging to Plasmodium spp. (phylum Apicomplexa) that produce significant morbidity and mortality, mostly in developing countries. Plasmodium parasites have a complex life cycle that includes multiple stages in anopheline mosquito vectors and vertebrate hosts. During the life cycle, the parasites undergo several cycles of extreme population growth within a brief span, and this is critical for their continued transmission and a contributing factor for their pathogenesis in the host. As with other eukaryotes, successful mitosis is an essential requirement for Plasmodium reproduction; however, some aspects of Plasmodium mitosis are quite distinct and not fully understood. In this review, we will discuss the current understanding of the architecture and key events of mitosis in Plasmodium falciparum and related parasites and compare them with the traditional mitotic events described for other eukaryotes. PMID:21317311

  6. Response to various periods of mechanical stimuli in Physarum plasmodium

    Science.gov (United States)

    Umedachi, Takuya; Ito, Kentaro; Kobayashi, Ryo; Ishiguro, Akio; Nakagaki, Toshiyuki

    2017-06-01

    Response to mechanical stimuli is a fundamental and critical ability for living cells to survive in hazardous conditions or to form adaptive and functional structures against force(s) from the environment. Although this ability has been extensively studied by molecular biology strategies, it is also important to investigate the ability from the viewpoint of biological rhythm phenomena so as to reveal the mechanisms that underlie these phenomena. Here, we use the plasmodium of the true slime mold Physarum polycephalum as the experimental system for investigating this ability. The plasmodium was repetitively stretched for various periods during which its locomotion speed was observed. Since the plasmodium has inherent oscillation cycles of protoplasmic streaming and thickness variation, how the plasmodium responds to various periods of external stretching stimuli can shed light on the other biological rhythm phenomena. The experimental results show that the plasmodium exhibits response to periodic mechanical stimulation and changes its locomotion speed depending on the period of the stretching stimuli.

  7. OCCURRENCE OF ANTI-Neospora caninum ANTIBODIES IN DOGS FROM CUIABÁ, MATO GROSSO STATE OCORRÊNCIA DE ANTICORPOS ANTI-Neospora caninum EM CÃES NOMUNICÍPIO DE CUIABÁ, MATO GROSSO

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    Ana Helena Benetti

    2008-04-01

    Full Text Available The aim of the study was to determine the presence and mixed and the fact of having or not access to the of antibodies anti-Neospora caninum by the Indirect streets. Antibodies were observed in 27 (45% dogs with Fluorescent Antibody Test (≥ 50 in serum samples from titers ranging from 50 to 1600. No association was found 60 dogs from the municipality of Cuiabá, Mato Grosso between the occurrence of antibodies anti-N. caninum State and to determine the associations between the and the sex, age and diet (P >0.05. However access to frequency of positive dogs and the sex, age (< 2 years, 2 the streets were associated with higher occurrence of N. to 4 years and > 4 years, diet (commercial, home made caninum antibodies (P <0.001.  KEY WORDS: Cuiabá, dogs, indirect fluorescent antibody test, Neospora caninum.

    O objetivo deste estudo foi avaliar a presença de anticorpos anti-Neospora caninum, por meio da reação de imunofluorescência indireta (≥ 50, em cães do município de Cuiabá, MT, bem como associar a freqüência de ani-mais soropositivos com o sexo, a faixa etária (< 2 anos, 2 a 4 anos e > 4 anos, a alimentação (caseira, comercial ou mista e o fato de terem ou não acesso às ruas. Dentre os 60 animais amostrados, 27 (45% apresentaram anticorpos anti-Neospora caninum com títulos que variaram de 50 a 1.600. Não foi encontrada associação (P>0,05 entre a ocorrência de anticorpos anti-N. caninum e o sexo, a faixa etária e o tipo de alimentação. Observou-se associação entre a positividade ao teste e o acesso ou não dos cães

  8. In silico and in vitro comparative activity of novel experimental derivatives against Leishmania major and Leishmania infantum promastigotes.

    Science.gov (United States)

    Khademvatan, Shahram; Adibpour, Neda; Eskandari, Alborz; Rezaee, Saeed; Hashemitabar, Mahmoud; Rahim, Fakher

    2013-10-01

    This in silico and in vitro comparative study was designed to evaluate the effectiveness of some biurets (K1 to K8) and glucantime against Leishmania major and Leishmania infantum promastigotes. Overall, eight experimental ligands and glucantime were docked using AutoDock 4.3 program into the active sites of Leishmania major and Leishmania infantum pteridine reductase 1, which were modeled using homology modeling programs. The colorimetric MTT assay was used to find L. major and L. infantum promastigotes viability at different concentrations of biuret derivatives in a concentration and time-dependent manner and the obtained results were expressed as 50% and 90% of inhibitory concentration (IC₅₀ and IC₉₀). In silico method showed that out of eight experimental ligands, four compounds were more active on pteridine reductase 1. K3 was the most active against L. major promastigotes with an IC₅₀ of 6.8 μM and an IC₉₀ of 40.2 μM, whereas for L. infantum promastigotes was K8 with IC₅₀ of 7.8 μM. The phenylethyl derivative (K7) showed less toxicity (IC₅₀s>60 μM) in both Leishmania strains. Glucantime displayed less growth inhibition in concentration of about 20 μM. In silico and especially docking results in a recent study were in accordance with the in vitro activity of these compounds in presented study and compound K3, K2 and K8 showed reasonable levels of selectivity for the Leishmania pteridine reductase 1. Copyright © 2013 Elsevier Inc. All rights reserved.

  9. Leishmania donovani Nucleoside Hydrolase terminal domains in cross-protective immunotherapy against Leishmania amazonensis murine infection

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    Dirlei eNico

    2014-06-01

    Full Text Available Nucleoside hydrolases of the Leishmania genus are vital enzymes for the replication of the DNA and conserved phylogenetic markers of the parasites. Leishmania donovani Nucleoside hydrolase (NH36 induced a main CD4+ T cell driven protective response against Leishmania chagasi infection in mice which is directed against its C-terminal domain. In this study, we used the three recombinant domains of NH36: N-terminal domain (F1, amino acids 1-103, central domain (F2 aminoacids 104-198 and C-terminal domain (F3 amino acids 199-314 in combination with saponin and assayed their immunotherapeutic effect on Balb/c mice previously infected with L. amazonensis. We identified that the F1 and F3 peptides determined strong cross-immunotherapeutic effects, reducing the size of footpad lesions to 48% and 64%, and the parasite load in footpads to 82.6% and 81%, respectively. The F3 peptide induced the strongest anti-NH36 antibody response and intradermal response (IDR against L. amazonenis and a high secretion of IFN-γ and TNF-α with reduced levels of IL-10. The F1 vaccine, induced similar increases of IgG2b antibodies and IFN-γ and TNF-α levels, but no IDR and no reduction of IL-10. The multiparameter flow cytometry analysis was used to assess the immune response after immunotherapy and disclosed that the degree of the immunotherapeutic effect is predicted by the frequencies of the CD4+ and CD8+ T cells producing IL-2 or TNF-α or both. Total frequencies and frequencies of double-cytokine CD4 T cell producers were enhanced by F1 and F3 vaccines. Collectively, our multifunctional analysis disclosed that immunotherapeutic protection improved as the CD4 responses progressed from 1+ to 2+, in the case of the F1 and F3 vaccines, and as the CD8 responses changed qualitatively from 1+ to 3+, mainly in the case of the F1 vaccine, providing new correlates of immunotherapeutic protection against cutaneous leishmaniasis in mice based on T-helper TH1 and CD8+ mediated

  10. PRODUÇÃO DE HIBRIDOMAS SECRETORES DE ANTICORPOS ANTI- Neospora caninum PARA USO EM IMUNODIAGNÓSTICO

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    Bruna Alves Devens

    2014-06-01

    Full Text Available The Neospora caninum is a protozoan Apicomplexa with greater involvement in abortions worldwide. The economic losses determined by neosporosis also include abortions besides the early disposal of cows, costs for replacing animals in the herd, drop in milk production as well as milk in fat production. The immunological diagnosis involves purchasing costly diagnostic kits on the market. Therefore, the aim of this study was the production of hybridomas secreting polyclonal antibodies with affinity to Neospora caninum (Nc-1 strain for immunodiagnostic use. For antibodies production, we used sonicated protozoa from Vero cells in culture, purified by filtration. These tachyzoites were employed for immunization of BALB / c mice using saponin as adjuvant, which allowed obtaining polyclonal antibodies capable of revealing fluorescein reaction in indirect immunofluorescence. The fusion of splenic cells, from the immunized mice with myeloma cells SP2 / 0 resulted in 72.4% hybridomas secreting anti-Nc-1antibodies. These hybridomas secreted antibodies positive to N. caninum and negative to Toxoplasma gondii.

  11. Clinical outcome and vertical transmission variability among canine Neospora caninum isolates in a pregnant mouse model of infection.

    Science.gov (United States)

    Dellarupe, Andrea; Regidor-Cerrillo, Javier; Jiménez-Ruiz, Elena; Schares, Gereon; Unzaga, Juan Manuel; Venturini, María Cecilia; Ortega-Mora, Luis M

    2014-03-01

    We compared the clinical outcome and vertical transmission of six canine Neospora caninum isolates using a pregnant BALB/c model. Four of the isolates were obtained from oocysts of naturally infected dogs (Nc-Ger2, Nc-Ger3, Nc-Ger6 and Nc-6Arg) and two were from diseased dogs with neurological signs (Nc-Bahia and Nc-Liv). The dams were inoculated with 2×106 tachyzoites of each isolate at day 7 of pregnancy. Morbidity, mortality and the antibody responses were evaluated in both the dams and the offspring, as was parasite transmission to the progeny. The mortality rates varied from 100% in Nc-Bahia and Nc-Liv-infected pups to 19% or less for those infected with the isolates from oocysts. The vertical transmission rates varied from 9 to 53% for N. caninum from oocysts, compared with 100% for the Nc-Liv and Nc-Bahia isolates. All dams showed specific IgG responses against tachyzoite and rNc-GRA7 antigens, confirming Neospora infection. The highest IgG levels were detected in mice inoculated with the Nc-Liv and Nc-Bahia isolates. These results demonstrate marked differences in virulence between the N. caninum isolates obtained from oocysts and neurologically affected dogs. This variability could help us to explain the differences in the outcome of the infection in definitive and intermediate hosts.

  12. Detection of Neospora caninum-DNA in feces collected from dogs in Shenyang (China) and ITS1 phylogenetic analysis.

    Science.gov (United States)

    Li, Jianhua; He, Pengfei; Yu, Yanhui; Du, Ling; Gong, Pengtao; Zhang, Guocai; Zhang, Xichen

    2014-09-15

    Neospora caninum is an intracellular protozoan that infects many domestic and wild animals. Dog is known as a definitive host of N. caninum and involved in transmitting infections to intermediate hosts by shedding oocysts. To investigate the epidemiology of dog neosporosis in China, 212 dog feces specimens in Shenyang were screened by nested-PCR using Nc5 primers and confirmed by N. caninum ITS1 PCR. The positive rate of N. caninum DNA was 34.90% (74/212). There were no significant correlations in prevalence of Neospora infections between different ages and genders. N. caninum DNA positive samples were further examined by PCR using Hammondia heydorni-specific primers. 37 out of 74 N. caninum DNA positive samples were also H. heydorni DNA positive. Only Nc5 primers positive and H. heydorni primers negative samples were used for ITS1 gene sequence analysis. Sequencing results from the 37 N. caninum positive samples revealed that ITS1 gene has 96-100% similarity with N. caninum sequences deposited in Genbank. Also, the presence of a new genotype indicated genetic polymorphism of N. caninum in infected dog feces in Shenyang of China. Copyright © 2014 Elsevier B.V. All rights reserved.

  13. Evaluation of vaccination with Neospora caninum protein for prevention of fetal loss associated with experimentally induced neosporosis in sheep.

    Science.gov (United States)

    Jenkins, Mark C; Tuo, Wenbin; Dubey, J P

    2004-10-01

    To evaluate the immunologic response of a killed tachyzoite vaccine against Neospora caninum and its effectiveness in preventing fetal loss associated with experimentally induced neosporosis in sheep. 30 Dorset ewes. Ewes were randomly allocated to receive vaccination on days 1 and 60 of the study with a killed N caninum tachyzoite preparation in a commercially available adjuvant or a saline-adjuvant mixture. A ram was placed on pasture with the ewes from days 15 to 60. Blood was collected from ewes before primary and booster vaccinations and prior to experimental challenge with N caninum tachyzoite performed on day 90; sera were assessed via Neospora agglutination (NA) and immunofluorescence antibody (IFA) assays. Blood was collected from lambs before they suckled, and sera were tested for antibodies against N caninum. Of the 14 vaccinated ewes that became pregnant, 12 gave birth to live-born lambs; in contrast, 5 of 11 pregnant control ewes gave birth to live-born lambs. Whereas vaccination improved fetal survival in pregnant ewes challenged with N caninum tachyzoites, it did not appear to have any appreciable effect on transmission of N caninum to offspring, as indicated by results of NA and IFA assays. The N caninum tachyzoite vaccine used in this study appeared to provide protection against fetal loss associated with experimentally induced neosporosis in a high proportion of pregnant ewes.

  14. Canine neutrophil extracellular traps release induced by the apicomplexan parasite Neospora Caninum in vitro

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    Zhengkai Wei

    2016-10-01

    Full Text Available Neosporosis is considered as one of the main causes of abortion and severe economic losses in dairy industry. The Canis genus serving as one of the confirmed definitive hosts of the apicomplexan parasite Neospora caninum (N. caninum plays a critical role in its life cycle. However, the effects of N. caninum on its definitive hosts of neutrophils extracellular traps (NETs formation remain unclear. In the present study, N. caninum tachyzoite-induced canine NETs formation was observed by scanning electron microscopy (SEM. Visualization of DNA decorated with H3, NE and MPO within N. caninum tachyzoite-induced NETs were examined using fluorescence confocal microscopy analyses. Furthermore, the formation of canine NETs was quantified using Sytox Green staining, and the LDH levels in supernatants were examined by an LDH Cytotoxicity Assay® kit. The results clearly showed that NETs-like structures were induced by N. caninum tachyzoites, and the major components within these structures induced by N. caninum tachyzoite were further confirmed by fluorescence confocal microscopy visualization. These results suggest that N. caninum tachyzoites strongly induced NETs formation in canine PMN. In functional inhibition assays, the blockings of NADPH oxidase, NE, MPO, SOCE, ERK 1/2 and p38 MAPK signaling pathways significantly inhibited N. caninum tachyzoite-induced NETs formation, which suggests that N. caninum tachyzoite-induced NETs formation is a NADPH oxidase-, NE-, MPO-, SOCE-, ERK 1/2- and p38 MAPK-dependent cell death process. To our knowledge, this study is the first to report the formation of NETs in canine PMN against N. caninum infection.

  15. Validation of 2 commercial Neospora caninum antibody enzyme linked immunosorbent assays

    Science.gov (United States)

    Wu, John T.Y.; Dreger, Sally; Chow, Eva Y.W.; Bowlby, Evelyn E.

    2002-01-01

    Abstract This is a validation study of 2 commercially available enzyme linked immunosorbent assays (ELISA) for the detection of antibodies against Neospora caninum in bovine serum. The results of the reference sera (n = 30) and field sera from an infected beef herd (n = 150) were tested by both ELISAs and the results were compared statistically. When the immunoblotting results of the reference bovine sera were compared to the ELISA results, the same identity score (96.67%) and kappa values (K) (0.93) were obtained for both ELISAs. The sensitivity and specificity values for the IDEXX test were 100% and 93.33% respectively. For the Biovet test 93.33% and 100% were obtained. The corresponding positive (PV+) and negative predictive (PV−) values for the 2 assays were 93.75% and 100% (IDEXX), and 100% and 93.75% (Biovet). In the 2nd study, competitive inhibition ELISA (c-ELISA) results on bovine sera from an infected herd were compared to the 2 sets of ELISA results. The identity scores of the 2 ELISAs were 98% (IDEXX) and 97.33% (Biovet). The K values calculated were 0.96 (IDEXX) and 0.95 (Biovet). For the IDEXX test the sensitivity and specificity were 97.56% and 98.53%, whereas for the Biovet assay 95.12% and 100% were recorded, respectively. The corresponding PV+ and PV− values were 98.77% and 97.1% (IDEXX), and 100% and 94.44% (Biovet). Our validation results showed that the 2 ELISAs worked equally well and there was no statistically significant difference between the performance of the 2 tests. Both tests showed high reproducibility, repeatability and substantial agreement with results from 2 other laboratories. A quality assurance based on the requirement of the ISO/IEC 17025 standards has been adopted throughout this project for test validation procedures. PMID:12418782

  16. Toltrazuril treatment to control diaplacental Neospora caninum transmission in experimentally infected pregnant mice.

    Science.gov (United States)

    Gottstein, B; Razmi, G R; Ammann, P; Sager, H; Müller, N

    2005-01-01

    We addressed the question whether diaplacental transmission of Neospora caninum can be controlled by metaphylactic chemotherapy using toltrazuril or enrofloxacin. Female C57/BL6 mice, infected on day 10 of pregnancy, were medicated for 6 consecutive days p.i. with 52.5 mg toltrazuril or - as an out-group control medication--16.7 mg enrofloxacin per kg body weight per day. Other control groups received either infection but no medication or vice versa. Toltrazuril treatment significantly reduced pre- and perinatal losses (10 deliveries of healthy newborns, versus 1 abortion and 4 failures) when compared to control-enrofloxacin (2 deliveries, versus 1 abortion, 7 failures and 2 pre-parturient deaths of dams) and non-treated animals (3 deliveries, versus 6 abortions, 8 failures and 4 pre-parturient deaths). Simultaneously, PCR-based parasite detection in the brain of mothers, histopathological findings as well as clinical fatality were significantly less frequent in toltrazuril-treated dams. The overall toltrazuril treatment efficacy was determined as 87 %, that of enrofloxacin-treatment as 17 %. The progenies of toltrazuril-treated dams also exhibited a very low rate of PCR-positivity in their brain (3 out of 39), whereas untreated dams delivered litters with mostly PCR-positive brains (12 out of 14) and a relatively high death rate post-partum (5 out of 19 newborns died). Mice subjected to a second mating delivered newborns all negative by N. caninum-PCR, indicating that diaplacental tachyzoite passage does not occur in a later, repeated pregnancy. Overall, our experiments showed that toltrazuril-treatment of an acute N. caninum-infection--induced during pregnancy--results in a clear reduction of fetal losses and a marked reduction of diaplacental passage of the parasite to the fetal brain, whereas enrofloxacin, as an out-group control substance, failed to show the same effect.

  17. Fetal death in cows experimentally infected with Neospora caninum at 110 days of gestation.

    Science.gov (United States)

    Almería, S; Araujo, R; Tuo, W; López-Gatius, F; Dubey, J P; Gasbarre, L C

    2010-05-11

    Neospora caninum is a major cause of abortion in cattle, but the reasons why some animals abort and not others remain unclear. Most of the N. caninum experimental primary infections in cattle late in gestation, after 120 days of pregnancy, result in birth of full-term congenitally infected fetuses. In the present study, the distribution of parasites and pathogenesis of infection in both dams and fetuses after inoculation with 10(7) culture derived tachyzoites of N. caninum NC-Illinois cattle strain at 110 days of gestation were analyzed at 3 weeks, 6 weeks and 9 weeks after infection (WAI) in eight Angus heifers. One dam from the group euthanized at 6 WAI had a dead fetus at necropsy. Extensive lesions were observed in the placenta and tachyzoites were detected in both the placenta and the fetus. The fetus was seropositive and had high IFN-gamma g production in fetal fluids. Another fetus, still alive when euthanized at 3 WAI, had severe lesions and high IFN-gamma production and a similar fate could have been expected if the experimental period would have been longer. Lesions in the placenta of the remaining six dams that had live fetuses at necropsy were mild. In those dams, the fetal and maternal placentas had not separated and contained focal areas of placentitis at the materno-fetal junction. Transplacental infection took place on all fetuses based on detection of parasitic DNA in fetal tissues. The present study shows that experimental N. caninum infection of naïve dams after 110 days of pregnancy can lead to fetal death. The results suggest that the severity of placental lesions and the strong IFN-gamma response in some fetuses, possibly as part of the immune response trying to control the high parasitemia, might, in fact, be the cause of their death. (c) 2010 Elsevier B.V. All rights reserved.

  18. Red foxes (Vulpes vulpes) are a natural intermediate host of Neospora caninum.

    Science.gov (United States)

    Almería, S; Ferrer, D; Pabón, M; Castellà, J; Mañas, S

    2002-08-22

    The present study was undertaken to determine if red foxes are natural intermediate and/or definitive host for Neospora caninum and to study the importance of infection of N. caninum in this species in North-eastern Spain. Faecal samples and brain tissues were obtained from 122 foxes from 21 rural areas of Catalonia. Faeces collected were examined for parasite eggs and coccidian oocysts using sucrose flotation. For PCR-based diagnosis of N. caninum in brain tissues, the specific genomic Nc5 region was selected as the target sequence for DNA amplification. To control for PCR failure and facilitate identification of truly negative samples, the competitor pNc5C molecule was added to all negative samples in a second round of PCR reactions. Of the 122 foxes analysed, 13 (10.7%) were positive by PCR for N. caninum. Signal intensities of all positive samples were relatively weak with the exception of one sample from a 3-month male animal, that also showed the highest repeatability. No differences were observed by sex, age or area of sampling analysis. Detection of stages of N. caninum in brain from naturally infected red foxes demonstrated that red foxes are a natural intermediate host for N. caninum. Faecal samples were analysed for the presence of N. caninum oocysts, however, no oocysts compatible with N. caninum were found. A widespread latent infection of red foxes in North-eastern Spain found in the present study indicates that red foxes could have a very important role in the epidemiology of neosporosis in our area.

  19. Neospora caninum: Seroprevalence in beef cattle in the mountainous region of Santa Catarina, Brazil

    Directory of Open Access Journals (Sweden)

    Mayckon Antonio Cardoso Padilha

    2017-03-01

    Full Text Available The distribution of Neospora caninum, an important agent of reproductive disorders in cattle, has been frequently reported in dairy cattle in Brazil and worldwide. Records of infection are less frequent in beef cattle. To determine the seroprevalence of bovine neosporosis, 507 beef cattle blood samples were collected from January 2013 to September 2015, from 16 municipalities of the Associação dos Municípios da Região Serrana (AMURES. Samples were tested for the presence of IgG antibodies ( ? 1:100 against N. caninum by indirect immunofluorescence antibody test (IFAT. Information about sex, age, and origin of the bovines were obtained from the Brazilian Bovine and Bubaline Identification and Certification System (SISBOV, and were tabulated for statistical analysis (Chi-square and Fisher Exact test, P ? 0.05. Of the 507 serum samples analyzed, 70 (13.81% contained antibodies against N. caninum with titers of 1:100 (16, 1:200 (22, 1:400 (17, 1:800 (nine, 1:1600 (four and 1:3200 (two. Positive specimens were collected from 13 of the 16 municipalities and across all age groups. Of the positive samples, there were no statistical differences between males and females (32.86% vs. 67.14%, P= 0.1072, age groups (P= 0.4116, or municipalities (P= 0.6838. While not statistically significant (P>0.05, higher seroprevalence was observed among older females. Although seroprevalence was relatively low, results indicate that infection by N. caninum in beef cattle is widespread in the studied region.

  20. Genetic characterization of Neospora caninum from aborted bovine foetuses in Aguascalientes, Mexico.

    Science.gov (United States)

    Medina-Esparza, Leticia; Regidor-Cerrillo, Javier; García-Ramos, Daniel; Álvarez-García, Gema; Benavides, Julio; Ortega-Mora, Luis Miguel; Cruz-Vázquez, Carlos

    2016-09-15

    The cyst-forming protozoan parasite Neospora caninum is one of the main causes of bovine abortion worldwide and is of great economic importance in the cattle industry. Recent studies have revealed extensive genetic variation among N. caninum isolates based on multilocus microsatellite genotyping. Currently, the most extensive study reported is based on the N. caninum genotyping of 96 samples from four countries on two continents (Spain, Argentina, Germany and Scotland) that demonstrate different clusters of multilocus genotypes (MLGs) implicated in cattle abortions as well as the population sub-structuring of N. caninum, which is partially associated with the geographical origin. The aim of this study was to genotype N. caninum from aborted bovine foetuses that originated from Mexico within the region of Aguascalientes and to investigate their genetic diversity. Parasite DNA was detected in 27 out of the 63 analysed foetuses recovered from 10 different herds. Complete or nearly complete profiles based on 9 microsatellite markers were obtained from 11 samples. Diverse N. caninum MLGs were implicated in the occurrence of abortion in each herd. All of the Mexican MLGs differed from the MLGs previously determined for the Argentinean, Spanish, German and Scottish N. caninum populations. The Mexican MLGs failed to cluster by eBURST analyses. The MLG relationships using PCoA showed a close genetic relationship between the Spanish population and a portion of the Mexican population, but a more distant genetic relationship with the Argentinean genotypes. These results demonstrate the genetic diversity of N. caninum in the studied areas that differed from other populations of N. caninum around the world. Copyright © 2016 Elsevier B.V. All rights reserved.

  1. Neospora caninum Recruits Host Cell Structures to Its Parasitophorous Vacuole and Salvages Lipids from Organelles

    Science.gov (United States)

    Nolan, Sabrina J.; Luechtefeld, Thomas

    2015-01-01

    Toxoplasma gondii and Neospora caninum, which cause the diseases toxoplasmosis and neosporosis, respectively, are two closely related apicomplexan parasites. They have similar heteroxenous life cycles and conserved genomes and share many metabolic features. Despite these similarities, T. gondii and N. caninum differ in their transmission strategies and zoonotic potential. Comparative analyses of the two parasites are important to identify the unique biological features that underlie the basis of host preference and pathogenicity. T. gondii and N. caninum are obligate intravacuolar parasites; in contrast to T. gondii, events that occur during N. caninum infection remain largely uncharacterized. We examined the capability of N. caninum (Liverpool isolate) to interact with host organelles and scavenge nutrients in comparison to that of T. gondii (RH strain). N. caninum reorganizes the host microtubular cytoskeleton and attracts endoplasmic reticulum (ER), mitochondria, lysosomes, multivesicular bodies, and Golgi vesicles to its vacuole though with some notable differences from T. gondii. For example, the host ER gathers around the N. caninum parasitophorous vacuole (PV) but does not physically associate with the vacuolar membrane; the host Golgi apparatus surrounds the N. caninum PV but does not fragment into ministacks. N. caninum relies on plasma lipoproteins and scavenges cholesterol from NPC1-containing endocytic organelles. This parasite salvages sphingolipids from host Golgi Rab14 vesicles that it sequesters into its vacuole. Our data highlight a remarkable degree of conservation in the intracellular infection program of N. caninum and T. gondii. The minor differences between the two parasites related to the recruitment and rearrangement of host organelles around their vacuoles likely reflect divergent evolutionary paths. PMID:25750213

  2. Neospora caninum in beef herds in New South Wales, Australia. 1: seroprevalence study.

    Science.gov (United States)

    Moloney, B J; Kirkland, P D; Heuer, C

    2017-03-01

    To determine the seroprevalence of Neospora caninum antibodies in beef breeding herds across New South Wales (NSW) and to determine if there are any differences associated with geographic location and other herd-level factors. Cross-sectional survey of beef breeding cows (n = 3298) from 63 properties (approximately 55 cows per herd) sampled randomly from six regions in NSW using a multistage survey design. Samples were tested by ELISA for N. caninum. Seroprevalence was determined at animal and herd levels, using an analysis approach to account for stratification, sample weighting and within-herd clustering. Animal-level seroprevalence ranged from 1.8% to 11.3% across regions and the overall animal seroprevalence for NSW was 5.9%. The mean within-herd seroprevalence was 5.2%. The herd seroprevalence ranged from 50% to 92%, with an overall point estimate for NSW of 63.8% (using ≥ 1 animal positive = herd positive). The within-herd seroprevalence ranged from 1.6% to 32.7% Prevalence and associated confidence limits were adjusted for the design of the survey. Overall, about two-thirds of all herds in NSW showed evidence of infection, but the seroprevalence of N. caninum in individual beef cattle in NSW was low to moderate (1.8-11.3%). Significant differences occurred between regions. The risk for herds being positive for N. caninum was associated with geographic factors, particularly in the Mid-North Coast Region. © 2017 State of New South Wales.

  3. Metabolic footprinting of extracellular metabolites of brain endothelium infected with Neospora caninum in vitro

    Science.gov (United States)

    2014-01-01

    Background The survival of the intracellular protozoan parasite Neospora caninum depends on its ability to adapt to changing metabolic conditions of the host cell. Thus, defining cellular and metabolic changes in affected target tissues may aid in delineating pathogenetic mechanism. We undertook this study to assess the metabolic response of human brain microvascular endothelial cells (HBMECs) to N. caninum infection in vitro. Methods HBMECs were exposed to N. caninum infection and the cytotoxic effects of infection were analyzed by the 3-(4,5-dimethyl-2-thiazolyl)-2,5-diphenyl-2H-tetrazoliumbromidin (MTT) assay and lactate dehydrogenase (LDH) release assay. Metabolic footprinting of the extracellular metabolites of parasite-infected and non-infected culture supernatant was determined by using targeted (Randox RX Imola clinical chemistry analyser) and unbiased RS (Raman microspectroscopy) approaches. Results The MTT assay did not reveal any cytotoxic effect of N. caninum challenge on host cell viability. Measurement of LDH activity showed that N. caninum significantly induced loss of cell membrane integrity in a time-dependent and dose-dependent manner compared to control cells. Targeted biochemical analysis revealed that beta hydroxybutyrate, pyruvate, ATP, total protein, non-esterified fatty acids, and triglycerides are significantly different in infected cells compared to controls. RS-based footprinting with principal component analysis (PCA) were able to correctly distinguish extracellular metabolites obtained from infected and control cultures, and revealed infection-related spectral signatures at 865 cm−1, 984 cm−1, 1046 cm−1, and 1420 cm−1, which are attributed to variations in the content of lipids and nucleic acids in infected cultures. Conclusions The changing pattern of extracellular metabolites suggests that HBMECs are target of metabolic alterations in N. caninum infection, which seem to reflect the changing metabolic state of infected

  4. Molecular analyses on Neospora caninum-triggered NETosis in the caprine system.

    Science.gov (United States)

    Villagra-Blanco, R; Silva, L M R; Gärtner, U; Wagner, H; Failing, K; Wehrend, A; Taubert, A; Hermosilla, C

    2017-07-01

    Neospora caninum is an obligate intracellular protozoan parasite causing serious reproductive disorders in large and small ruminants worldwide. Polymorphonuclear neutrophils (PMN) react against multiple invading pathogens through different mechanisms including the release of neutrophil extracellular traps (NETs). Here, in vitro interactions of caprine PMN and N. caninum tachyzoites were studied. Scanning electron microscopic- and immunofluorescence-analyses demonstrated that caprine PMN undergo NETosis upon contact with tachyzoites of N. caninum, extruding filaments that entrap parasites. Detailed co-localization studies of N. caninum tachyzoite-induced NETs revealed the presence of PMN-derived DNA being decorated with histones (H1, H2A/H2B, H3,H4) and neutrophil elastase (NE) corroborating the molecular characteristics of classical mammalian NETs. As a new result for parasite-induced NETosis, we identified pentraxin and cathepsin B in N. caninum-triggered NETs. Nonetheless, functional inhibition assays revealed that during caprine NET formation triggered by N. caninum different molecular signaling pathways are induced, when compared to other apicomplexan parasites or host species. As such, N. caninum-induced NETosis appears to be influenced by MPO but independent of NADPH oxidase, SOCE, ERK1/2 and p38 MAPK activities. Furthermore, the inhibition of PMN autophagy via blockage of the PI3K-mediated signaling pathway failed to influence tachyzoite-induced NETosis. Since N. caninum-tachyzoites induced caprine NETosis, this effector mechanism should be considered as an early host immune response during acute caprine neosporosis. Copyright © 2017 Elsevier Ltd. All rights reserved.

  5. Assessment of transplacental transmission of Neospora caninum in dairy cattle in the Agreste region of Pernambuco

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    Inalda Angélica de Souza Ramos

    Full Text Available Abstract The transplacental transmission is the primary route of Neospora caninum infection in bovine herds around the world. This study aimed to determine the frequency of transplacental transmission of the parasite in dairy cattle of Agreste region of Pernambuco through serological tests (IFAT and ELISA. Three hundred sixteen serum samples from cows and heifers and their offspring were analyzed. The transplacental transmission rate was 72.22% (13/18 for cows and 69.23% (9/13 for heifers by IFAT. ELISA test showed transplacental transmission rate of 43.58% (17/39 for cows and 50% (9/18 for heifers. The transplacental transmission rates were similar, in both groups in test, but a higher seropositivity was found in cows by IFAT. Data were statistically analyzed using the chi-square and Fisher’s exact test. A significant relationship of dependence between seropositivity of mothers and their offspring was found. The more frequent IFAT antibody titers and ELISA levels for N. caninum were, respectively, 200 and between four (cows and five (heifers and offspring. In the Spearman correlation, no association was found between the magnitude of antibody titers for N. caninum between mothers and their offspring. The kappa test showed an index of 0.35, indicating a mild correlation between the serological tests used. The study suggests that cows and heifers are the main transmitters of N. caninum in the studied region and that vertical transmission is the major form of transmission in dairy herds of the Agreste region of Pernambuco.

  6. Bovine Polymorphonuclear Neutrophils Cast Neutrophil Extracellular Traps against the Abortive Parasite Neospora caninum

    Science.gov (United States)

    Villagra-Blanco, Rodolfo; Silva, Liliana M. R.; Muñoz-Caro, Tamara; Yang, Zhengtao; Li, Jianhua; Gärtner, Ulrich; Taubert, Anja; Zhang, Xichen; Hermosilla, Carlos

    2017-01-01

    Neospora caninum represents a relevant apicomplexan parasite causing severe reproductive disorders in cattle worldwide. Neutrophil extracellular trap (NET) generation was recently described as an efficient defense mechanism of polymorphonuclear neutrophils (PMN) acting against different parasites. In vitro interactions of bovine PMN with N. caninum were analyzed at different ratios and time spans. Extracellular DNA staining was used to illustrate the typical molecules of NETs [i.e., histones (H3), neutrophil elastase (NE), myeloperoxidase (MPO), pentraxin] via antibody-based immunofluorescence analyses. Functional inhibitor treatments were applied to reveal the role of several enzymes [NADPH oxidase (NOX), NE, MPO, PAD4], ATP-dependent P2Y2 receptor, store-operated Ca++entry (SOCE), CD11b receptor, ERK1/2- and p38 MAPK-mediated signaling pathway in tachyzoite-triggered NETosis. N. caninum tachyzoites triggered NETosis in a time- and dose-dependent manner. Scanning electron microscopy analyses revealed NET structures being released by bovine PMN and entrapping tachyzoites. N. caninum-induced NET formation was found not to be NOX-, NE-, MPO-, PAD4-, ERK1/2-, and p38 MAP kinase-dependent process since inhibition of these enzymes led to a slight decrease of NET formation. CD11b was also identified as a neutrophil receptor being involved in NETosis. Furthermore, N. caninum-triggered NETosis depends on Ca++ influx as well as neutrophil metabolism since both the inhibition of SOCE and of P2Y2-mediated ATP uptake diminished NET formation. Host cell invasion assays indicated that PMN-derived NETosis hampered tachyzoites from active host cell invasion, thereby inhibiting further intracellular replication. NET formation represents an early and effective mechanism of response of the innate immune system, which might reduce initial infection rates during the acute phase of cattle neosporosis. PMID:28611772

  7. Buparvaquone is active against Neospora caninum in vitro and in experimentally infected mice

    Science.gov (United States)

    Müller, Joachim; Aguado-Martinez, Adriana; Manser, Vera; Balmer, Vreni; Winzer, Pablo; Ritler, Dominic; Hostettler, Isabel; Arranz-Solís, David; Ortega-Mora, Luis; Hemphill, Andrew

    2015-01-01

    The naphthoquinone buparvaquone is currently the only drug used against theileriosis. Here, the effects of buparvaquone were investigated in vitro and in an experimental mouse model for Neospora caninum infection. In 4-day proliferation assays, buparvaquone efficiently inhibited N. caninum tachyzoite replication (IC50 = 4.9 nM; IC100 = 100 nM). However, in the long term tachyzoites adapted and resumed proliferation in the presence of 100 nM buparvaquone after 20 days of cultivation. Parasiticidal activity was noted after 9 days of culture in 0.5 µM or 6 days in 1 µM buparvaquone. TEM of N. caninum infected fibroblasts treated with 1 µM buparvaquone showed that the drug acted rather slowly, and ultrastructural changes were evident only after 3–5 days of treatment, including severe alterations in the parasite cytoplasm, changes in the composition of the parasitophorous vacuole matrix and a diminished integrity of the vacuole membrane. Treatment of N. caninum infected mice with buparvaquone (100 mg/kg) either by intraperitoneal injection or gavage prevented neosporosis symptoms in 4 out of 6 mice in the intraperitoneally treated group, and in 6 out of 7 mice in the group receiving oral treatment. In the corresponding controls, all 6 mice injected intraperitoneally with corn oil alone died of acute neosporosis, and 4 out of 6 mice died in the orally treated control group. Assessment of infection intensities in the treatment groups showed that, compared to the drug treated groups, the controls showed a significantly higher parasite load in the lungs while cerebral parasite load was higher in the buparvaquone-treated groups. Thus, although buparvaquone did not eliminate the parasites infecting the CNS, the drug represents an interesting lead with the potential to eliminate, or at least diminish, fetal infection during pregnancy. PMID:25941626

  8. Neospora caninum associated with epidemic abortions in dairy cattle: the first clinical neosporosis report in Turkey.

    Science.gov (United States)

    Kul, Oğuz; Kabakci, Nalan; Yildiz, Kader; Ocal, Naci; Kalender, Hakan; Ilkme, N Aycan

    2009-01-22

    Neospora caninum, a protozoan parasite, has been considered as one of the most important etiological agents responsible for abortion in dairy cattle throughout the world since it was first identified in dogs in 1988. In this report, characteristics of neosporosis, detected in a dairy cow ranch having epidemic abortions as high as 18.4%, were described. Blood samples were collected from 25 infertile or aborted dairy cattle, 6 calves born in 2006 and 40 heifers that were born in 2005 and raised in the same ranch. Necropsy was conducted in a 20-day-old Simmental calf that exhibited neurological signs including incoordination, head shaking, hyperextension in forelimbs and hindlimbs and tremor. The seroprevalance in aborted or infertile dairy cattle, heifers, and calves was 60%, 40%, and 33.3%, respectively. The mothers of seropositive two calves including clinically affected calf and its dam were N. caninum seropositive. In immunoperoxidase examinations, N. caninum antigen immunopositivity was observed in the degenerative and necrotic neurons in the brain, cerebellum as well as neurons in dorsal root ganglia of the cervical and thoracic regions of the spinal cord. In the heart, myocytes and Purkinje cells exhibited granular and linear patterns of immunoreactivity. Striated myofibers around the eyeball also showed immunolocalization for N. caninum antigen. Ultrastructurally, tachyzoites with typical apical complex, rhoptries and double-layered parasitic membrane were detected in the brain and heart sections. In conclusion, this report described clinical neosporosis for the first time in Turkey with tissue localization of the causative agents. This scientific communication also discusses the possible impact of cattle neosporosis by clinical, serologic and pathologic evidences collected from the survey of calves born in two successive generations in a ranch.

  9. Vaccines against a Major Cause of Abortion in Cattle, Neospora caninum Infection

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    Andrew Hemphill

    2011-09-01

    Full Text Available Neosporosis, caused by the apicomplexan parasite Neospora caninum, represents one of the economically most important causes of abortion in cattle. During pregnancy, the parasite infects the placental tissue and the fetus, which can lead to stillbirth, abortion, or birth of weak calves. Alternatively, calves are born without clinical symptoms, but they can carry over the parasite to the next generation. In addition, N. caninum causes neuromuscular disease in dogs. The economic importance of neosporosis has prompted researchers to invest in the development of measures to prevent infection of cattle by vaccination. A good vaccine must stimulate protective cellular immune responses as well as antibody responses at mucosal sites and, systemically, must activate T-helper cells to produce relevant cytokines, and must elicit specific antibodies that aid in limiting parasite proliferation, e.g., by interference with host cell invasion, activation of complement, and/or opsonization of parasites to have them killed by macrophages. Different types of vaccines have been investigated, either in bovines or in the mouse model. These include live vaccines such as naturally less virulent isolates of N. caninum, attenuated strains generated by irradiation or chemical means, or genetically modified transgenic strains. Live vaccines were shown to be very effective; however, there are serious disadvantages in terms of safety, costs of production, and stability of the final product. Subunit vaccines have been intensively studied, as they would have clear advantages such as reduced costs in production, processing and storage, increased stability and shelf life. The parasite antigens involved in adhesion and invasion of host cells, such as surface constituents, microneme-, rhoptry- and dense granule-components represent interesting targets. Subunit vaccines have been applied as bacterially expressed recombinant antigens or as DNA vaccines. Besides monovalent vaccines

  10. Immune response in the adipose tissue of lean mice infected with the protozoan parasite Neospora caninum

    Science.gov (United States)

    Teixeira, Luzia; Moreira, João; Melo, Joana; Bezerra, Filipa; Marques, Raquel M; Ferreirinha, Pedro; Correia, Alexandra; Monteiro, Mariana P; Ferreira, Paula G; Vilanova, Manuel

    2015-01-01

    The adipose tissue can make important contributions to immune function. Nevertheless, only a limited number of reports have investigated in lean hosts the immune response elicited in this tissue upon infection. Previous studies suggested that the intracellular protozoan Neospora caninum might affect adipose tissue physiology. Therefore, we investigated in mice challenged with this protozoan if immune cell populations within adipose tissue of different anatomical locations could be differently affected. Early in infection, parasites were detected in the adipose tissue and by 7 days of infection increased numbers of macrophages, regulatory T (Treg) cells and T-bet+ cells were observed in gonadal, mesenteric, omental and subcutaneous adipose tissue. Increased expression of interferon-γ was also detected in gonadal adipose tissue of infected mice. Two months after infection, parasite DNA was no longer detected in these tissues, but T helper type 1 (Th1) cell numbers remained above control levels in the infected mice. Moreover, the Th1/Treg cell ratio was higher than that of controls in the mesenteric and subcutaneous adipose tissue. Interestingly, chronically infected mice presented a marked increase of serum leptin, a molecule that plays a role in energy balance regulation as well as in promoting Th1-type immune responses. Altogether, we show that an apicomplexa parasitic infection influences immune cellular composition of adipose tissue throughout the body as well as adipokine production, still noticed at a chronic phase of infection when parasites were already cleared from that particular tissue. This strengthens the emerging view that infections can have long-term consequences for the physiology of adipose tissue. PMID:25581844

  11. Prevalence of Malaria Plasmodium in Abeokuta, Nigeria

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    Okonko, I. O.

    2009-01-01

    Full Text Available This study reports the prevalence of malaria caused by plasmodium between genders in Abeokuta, the capital city of Ogun State located in the forest zone of southwestern Nigeria between January 2002 and December 2004. Blood film examination for malaria parasites in 708 patients; 366 males and 342 females. Microscopic examination of thick films techniques was employed for this study. Of the 708 (100% patients examined, 577 (81.5% were Plasmodium-positive. A high malaria parasite prevalence rate of 81.5% was noted in this study. Female subjects were more infected (42.4% than males (41.9% however, there was no significant difference in the sex of the subjects studied (p=0.05. A high malaria parasite prevalence rate of 86.9% was noted in samples collected in year 2003 than in other years studied. There was significant difference in the years under study (p=0.05. This study shows that a good percentage of people were infested by malaria Plasmodium. This could be attributed to lack of adequate accommodation and poor sanitary conditions in the area under study. Although several efforts have been made to effectively control the high incidence of malaria in Nigeria, these have been largely unsuccessful due to a number of reasons such as irrigated urban agriculture which can be the malaria vector’s breeding ground in the city, stagnant gutters and swamps in our environment where mosquitoes breed in millions, and lack of political will and commitment of the government in its disease management program, low awareness of the magnitude of malaria problem, poor health practices by individuals and communities and resistance to drugs. Therefore, future interventions in Nigeria should be directed toward controlling malaria in the context of a moderate transmission setting; thus, large-scale distribution of insecticide-treated nets or widespread use of indoor residual spraying may be less cost-effective than enhanced surveillance with effective case management or

  12. Laser-induced inactivation of Plasmodium falciparum

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    LeBlanc Danielle

    2012-08-01

    Full Text Available Abstract Background Haemozoin crystals, produced by Plasmodium during its intra-erythrocytic asexual reproduction cycle, can generate UV light via the laser-induced, non-linear optical process of third harmonic generation (THG. In the current study the feasibility of using haemozoin, constitutively stored in the parasite’s food vacuole, to kill the parasite by irradiation with a near IR laser was evaluated. Methods Cultured Plasmodium parasites at different stages of development were irradiated with a pulsed NIR laser and the viability of parasites at each stage was evaluated from their corresponding growth curves using the continuous culture method. Additional testing for germicidal effects of haemozoin and NIR laser was performed by adding synthetic haemozoin crystals to Escherichia coli in suspension. Cell suspensions were then irradiated with the laser and small aliquots taken and spread on agar plates containing selective agents to determine cell viability (CFU. Results Parasites in the late-trophozoites form as well as trophozoites in early-stage of DNA synthesis were found to be the most sensitive to the treatment with ~4-log reduction in viability after six passes through the laser beam; followed by parasites in ring phase (~2-log reduction. A ~1-log reduction in E. coli viability was obtained following a 60 min irradiation regimen of the bacteria in the presence of 1 μM synthetic haemozoin and a ~2-log reduction in the presence of 10 μM haemozoin. Minimal (≤15% cell kill was observed in the presence of 10 μM haemin. Conclusions Laser-induced third-harmonic generation by haemozoin can be used to inactivate Plasmodium. This result may have clinical implications for treating severe malaria symptoms by irradiating the patient’s blood through the skin or through dialysis tubing with a NIR laser.

  13. [Reaction of Leishmania (Leishmania) mexicana antigens by sera of patients with cutaneous leishmaniasis from Sinaloa, Mexico].

    Science.gov (United States)

    Salazar-Mejía, Patricia Guadalupe; Tejeda-Aguirre, Celia Rosa; López-Moreno, Héctor Samuel

    2010-01-01

    To detect Leishmania mexicana antigens reacting with sera of patients with cutaneous leishmaniasis (CL). A crude extract of L. mexicana was used as antigen for 2-D Western blot using sera from 5 patients with CL and controls from Sinaloa, Mexico during 2008. Five antigens were detected in the five infected patients analyzed; their molecular weights and isoelectric points were: 26 kDa (pI 7.8), 27 kDa (pI 8.1), 28 kDa (pI 8.6), 29 kDa (pI 8.5) and 31 kDa (pI 9.0). New potentially immunodominant L. mexicana antigens were detected, suggesting that this parasite could be the species responsible for human infection in Sinaloa.

  14. Serological and molecular survey of Leishmania parasites in apparently healthy dogs in the West Bank, Palestine

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    Hamarsheh Omar

    2012-08-01

    Full Text Available Abstract Background Canine visceral leishmaniasis (CVL is caused by Leishmania infantum in all Mediterranean countries. The Leishmania parasite is transmitted by the bite of a corresponding sand fly vector and primarily maintained in nature by wild and domestic reservoirs, including dogs, foxes and jackals. Infected dogs are the primary reservoir host in endemic regions and are the most significant risk disposing humans to infection. The present study aimed at assessing the prevalence of infection with Leishmania and identification of Leishmania infantum in domestic dogs in the West Bank, Palestine. Methods The infection rate among domestic dogs collected from seven districts in the Palestinian West Bank was investigated by examination of parasites in culture from the buffy coat using serological and molecular methods; based on ELISA, internal transcribed spacer 1 (ITS1 and cysteine protease (CPB PCR. Results Out of 215 dogs examined for Leishmania, 36 (16.7% were positive in at least one method. Twenty three animals (11.5% were positive for Leishmania DNA, whereas, ELISA and culture revealed 16 (7.5%, and 4 (1.5% respectively. CPB-PCR on one of three culture-positive isolates revealed Leishmania infantum as the causative agent for Leishmania infection in dogs. Conclusions Our study showed that canine leishmania infection is prevalent with varying degrees in all the seven studied districts in Palestine despite the absence of human VL cases in 4 of these districts. The causative agent was confirmed to be Leishmania infantum.

  15. Tetracycline-inducible gene expression system in Leishmania mexicana

    Czech Academy of Sciences Publication Activity Database

    Kraeva, N.; Ishemgulova, A.; Lukeš, Julius; Yurchenko, Vyacheslav

    2014-01-01

    Roč. 198, č. 1 (2014), s. 11-13 ISSN 0166-6851 R&D Projects: GA MŠk(CZ) EE2.3.30.0032 Institutional support: RVO:60077344 Keywords : Leishmania mexicana * Gene expression * Tet-inducible system Subject RIV: EB - Genetics ; Molecular Biology Impact factor: 1.787, year: 2014

  16. Patchy Parasitized Skin Governs Leishmania donovani Transmission to Sand Flies.

    Science.gov (United States)

    Kamhawi, Shaden; Serafim, Tiago D

    2017-10-01

    Doehl et al. have combined empirical data with computer simulation to demonstrate that RAG-2 mice intravenously infected with Leishmania donovani form heterogeneous skin parasite patches that govern infectiousness to sand flies. This model provides a much-needed tool to explore the relevance of asymptomatic and symptomatic visceral leishmaniasis patients as infection reservoirs. Published by Elsevier Ltd.

  17. Sand fly evolution and its relationship to Leishmania transmission

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    PD Ready

    2000-08-01

    Full Text Available The evolutionary relationships of sand flies and Leishmania are discussed in this report, which draws distinctions between co-association, co-evolution and co-speciation (or co-cladogenesis. Examples focus on Phlebotomus vectors of Le. infantum and Le. major in the Mediterranean subregion.

  18. Histone H1 regulates chromatin condensation in Leishmania parasites.

    Science.gov (United States)

    Masina, Slavica; Zangger, Haroun; Rivier, Denis; Fasel, Nicolas

    2007-05-01

    We investigated the functional role of the Leishmania histone H1 and demonstrate for the first time that addition of histone H1 has a strong effect on microccocal digestion, chromatin condensation of parasite nuclei and that its overexpression can modulate parasite infectivity in vivo.

  19. Vectorborne Transmission of Leishmania infantum from Hounds, United States

    Science.gov (United States)

    Schaut, Robert G.; Robles-Murguia, Maricela; Juelsgaard, Rachel; Esch, Kevin J.; Bartholomay, Lyric C.; Ramalho-Ortigao, Marcelo

    2015-01-01

    Leishmaniasis is a zoonotic disease caused by predominantly vectorborne Leishmania spp. In the United States, canine visceral leishmaniasis is common among hounds, and L. infantum vertical transmission among hounds has been confirmed. We found that L. infantum from hounds remains infective in sandflies, underscoring the risk for human exposure by vectorborne transmission. PMID:26583260

  20. Natural Sesquiterpene Lactones Induce Oxidative Stress in Leishmania mexicana

    NARCIS (Netherlands)

    Barrera, P.; Sulsen, V.P.; Lozano, E.; Rivera, M.; Beer, M.F.; Tonn, C.; Martino, V.S.; Sosa, M.A.

    2013-01-01

    Leishmaniasis is a worldwide parasitic disease, caused by monoflagellate parasites of the genus Leishmania. In the search for more effective agents against these parasites, the identification of molecular targets has been attempted to ensure the efficiency of drugs and to avoid collateral damages on

  1. Vaccinations with live-attenuated Leishmania major promastigotes ...

    African Journals Online (AJOL)

    Background: Currently there is no vaccine available in use against any form of leishmaniases worldwide. Objective: To assess potential of a live-attenuated Leishmania major promastigates, for protection against a challenge infection with L. major in BALB/c mice. Design. A laboratory based study. Setting: Study was carried ...

  2. Refractoriness to Leishmania donovani and L. major in ...

    African Journals Online (AJOL)

    In the first of a series of experiments, a wild rock pigeon (Columba guinea), a wild guinea fowl (Numidia meleagris), a domestic chicken (Gallus gallus) and a domestic feral pigeon (Columbia livia) were subcutaneously challenged each with 1´107 culture-derived stationary phase Leishmania major (NLB-144) promastigotes ...

  3. Genetic Diversity in Natural Populations of New World Leishmania

    Directory of Open Access Journals (Sweden)

    Cupolillo Elisa

    1998-01-01

    Full Text Available Our results have shown the wide diversity of parasites within New World Leishmania. Biochemical and molecular characterization of species within the genus has revealed that much of the population heterogeneity has a genetic basis. The source of genetic diversity among Leishmania appears to arise from predominantly asexual, clonal reproduction, although occasional bouts of sexual reproduction can not be ruled out. Genetic variation is extensive with some clones widely distributed and others seemingly unique and localized to a particular endemic focus. Epidemiological studies of leishmaniasis has been directed to the ecology and dynamics of transmission of Leishmania species/variants, particularly in localized areas. Future research using molecular techniques should aim to identify and follow Leishmania types in nature and correlate genetic typing with important clinical characteristics such as virulence, pathogenicity, drug resistance and antigenic variation. The epidemiological significance of such variation not only has important implications for the control of the leishmaniases, but would also help to elucidate the evolutionary biology of the causative agents.

  4. Vector transmission of leishmania abrogates vaccine-induced protective immunity.

    Directory of Open Access Journals (Sweden)

    Nathan C Peters

    2009-06-01

    Full Text Available Numerous experimental vaccines have been developed to protect against the cutaneous and visceral forms of leishmaniasis caused by infection with the obligate intracellular protozoan Leishmania, but a human vaccine still does not exist. Remarkably, the efficacy of anti-Leishmania vaccines has never been fully evaluated under experimental conditions following natural vector transmission by infected sand fly bite. The only immunization strategy known to protect humans against natural exposure is "leishmanization," in which viable L. major parasites are intentionally inoculated into a selected site in the skin. We employed mice with healed L. major infections to mimic leishmanization, and found tissue-seeking, cytokine-producing CD4+ T cells specific for Leishmania at the site of challenge by infected sand fly bite within 24 hours, and these mice were highly resistant to sand fly transmitted infection. In contrast, mice vaccinated with a killed vaccine comprised of autoclaved L. major antigen (ALM+CpG oligodeoxynucleotides that protected against needle inoculation of parasites, showed delayed expression of protective immunity and failed to protect against infected sand fly challenge. Two-photon intra-vital microscopy and flow cytometric analysis revealed that sand fly, but not needle challenge, resulted in the maintenance of a localized neutrophilic response at the inoculation site, and removal of neutrophils following vector transmission led to increased parasite-specific immune responses and promoted the efficacy of the killed vaccine. These observations identify the critical immunological factors influencing vaccine efficacy following natural transmission of Leishmania.

  5. Development and Production of a Leishmania Skin Test

    Science.gov (United States)

    2009-03-01

    Leishmania Skin Test PRINCIPAL INVESTIGATOR: Harry S. Neilsen, Jr., Ph . D. CONTRACTING ORGANIZATION: Allermed Laboratories, Inc. San...parasitophorous vacuole, and infect other target cells. After a blood meal from an infected host, amastigotes are released into the gut of sand flies where they...Systemic reactions also can occur including urticaria, gastrointestinal disturbances and respiratory distress leading to anaphylaxis. Study subjects

  6. Leishmania amazonensis Engages CD36 to Drive Parasitophorous Vacuole Maturation.

    Directory of Open Access Journals (Sweden)

    Kendi Okuda

    2016-06-01

    Full Text Available Leishmania amastigotes manipulate the activity of macrophages to favor their own success. However, very little is known about the role of innate recognition and signaling triggered by amastigotes in this host-parasite interaction. In this work we developed a new infection model in adult Drosophila to take advantage of its superior genetic resources to identify novel host factors limiting Leishmania amazonensis infection. The model is based on the capacity of macrophage-like cells, plasmatocytes, to phagocytose and control the proliferation of parasites injected into adult flies. Using this model, we screened a collection of RNAi-expressing flies for anti-Leishmania defense factors. Notably, we found three CD36-like scavenger receptors that were important for defending against Leishmania infection. Mechanistic studies in mouse macrophages showed that CD36 accumulates specifically at sites where the parasite contacts the parasitophorous vacuole membrane. Furthermore, CD36-deficient macrophages were defective in the formation of the large parasitophorous vacuole typical of L. amazonensis infection, a phenotype caused by inefficient fusion with late endosomes and/or lysosomes. These data identify an unprecedented role for CD36 in the biogenesis of the parasitophorous vacuole and further highlight the utility of Drosophila as a model system for dissecting innate immune responses to infection.

  7. Isolation of Leishmania tropica from an Ethiopian cutaneous leishmaniasis patient

    NARCIS (Netherlands)

    Hailu, Asrat; Di Muccio, Trentina; Abebe, Tamrat; Hunegnaw, Mesfin; Kager, Piet A.; Gramiccia, Marina

    2006-01-01

    Cutaneous leishmaniasis (CL) in the Old World is caused mainly by three species of Leishmania: L. major, L. tropica and L. aethiopica, and sporadically by L. infantum and L. donovani. In Ethiopia, zoonotic cutaneous leishmaniasis, caused by L. aethiopica, is a major public health problem affecting

  8. Biosynthesis of silver nanoparticles by Leishmania tropica | Rahi ...

    African Journals Online (AJOL)

    A novel biosynthesis route for Silver Nanoparticles (Ag-NPs) was attempted in the present study using Leishmania tropica the causative agent of cutaneous leishmaniasis in different countries, particularly in Mediterranean region in Iraq. Silver nanoparticles were successfully synthesized from AgNO3 by reduction of ...

  9. Leishmania development in sand flies: parasite-vector interactions overview.

    Science.gov (United States)

    Dostálová, Anna; Volf, Petr

    2012-12-03

    Leishmaniases are vector-borne parasitic diseases with 0.9 - 1.4 million new human cases each year worldwide. In the vectorial part of the life-cycle, Leishmania development is confined to the digestive tract. During the first few days after blood feeding, natural barriers to Leishmania development include secreted proteolytic enzymes, the peritrophic matrix surrounding the ingested blood meal and sand fly immune reactions. As the blood digestion proceeds, parasites need to bind to the midgut epithelium to avoid being excreted with the blood remnant. This binding is strictly stage-dependent as it is a property of nectomonad and leptomonad forms only. While the attachment in specific vectors (P. papatasi, P. duboscqi and P. sergenti) involves lipophosphoglycan (LPG), this Leishmania molecule is not required for parasite attachment in other sand fly species experimentally permissive for various Leishmania. During late-stage infections, large numbers of parasites accumulate in the anterior midgut and produce filamentous proteophosphoglycan creating a gel-like plug physically obstructing the gut. The parasites attached to the stomodeal valve cause damage to the chitin lining and epithelial cells of the valve, interfering with its function and facilitating reflux of parasites from the midgut. Transformation to metacyclic stages highly infective for the vertebrate host is the other prerequisite for effective transmission. Here, we review the current state of knowledge of molecular interactions occurring in all these distinct phases of parasite colonization of the sand fly gut, highlighting recent discoveries in the field.

  10. Vaccination using live attenuated Leishmania donovani centrin deleted parasites induces protection in dogs against Leishmania infantum.

    Science.gov (United States)

    Fiuza, Jacqueline Araújo; Gannavaram, Sreenivas; Santiago, Helton da Costa; Selvapandiyan, Angamuthu; Souza, Daniel Menezes; Passos, Lívia Silva Araújo; de Mendonça, Ludmila Zanandreis; Lemos-Giunchetti, Denise da Silveira; Ricci, Natasha Delaqua; Bartholomeu, Daniella Castanheira; Giunchetti, Rodolfo Cordeiro; Bueno, Lilian Lacerda; Correa-Oliveira, Rodrigo; Nakhasi, Hira L; Fujiwara, Ricardo Toshio

    2015-01-03

    Live attenuated Leishmania donovani parasites such as LdCen(-/-) have been shown elicit protective immunity against leishmanial infection in mice and hamster models. Previously, we have reported on the induction of strong immunogenicity in dogs upon vaccination with LdCen(-/-) including an increase in immunoglobulin isotypes, higher lymphoproliferative response, higher frequencies of activated CD4(+) and CD8(+) T cells, IFN-γ production by CD8(+) T cells, increased secretion of TNF-α and IL-12/IL-23p40 and, finally, decreased secretion of IL-4. To further explore the potential of LdCen(-/-) parasites as vaccine candidates, we performed a 24-month follow up of LdCen(-/-) immunized dogs after challenge with virulent Leishmania infantum, aiming determination of parasite burden by qPCR, antibody production (ELISA) and cellular responses (T cell activation and cytokine production) by flow cytometry and sandwich ELISA. Our data demonstrated that vaccination with a single dose of LdCen(-/-) (without any adjuvant) resulted in the reduction of up to 87.3% of parasite burden after 18 months of virulent challenge. These results are comparable to those obtained with commercially available vaccine in Brazil (Leishmune(®)). The protection was associated with antibody production and CD4(+) and CD8(+) proliferative responses, as well as T cell activation and significantly higher production of IFN-γ, IL-12/IL-23p40 and TNF-α, which was comparable to responses induced by immunization with Leishmune(®), with significant differences when compared to control animals (Placebo). Moreover, only animals immunized with LdCen(-/-) expressed lower levels of IL-4 when compared to animals vaccinated either with Leishmune(®) or PBS. Our results support further studies aiming to demonstrate the potential of genetically modified live attenuated L. donovani vaccine to control L. infantum transmission in endemic areas for CVL. Copyright © 2014 Elsevier Ltd. All rights reserved.

  11. The Genetic Relationship between Leishmania aethiopica and Leishmania tropica Revealed by Comparing Microsatellite Profiles.

    Science.gov (United States)

    Krayter, Lena; Schnur, Lionel F; Schönian, Gabriele

    2015-01-01

    Leishmania (Leishmania) aethiopica and L. (L.) tropica cause cutaneous leishmaniases and appear to be related. L. aethiopica is geographically restricted to Ethiopia and Kenya; L. tropica is widely dispersed from the Eastern Mediterranean, through the Middle East into eastern India and in north, east and south Africa. Their phylogenetic inter-relationship is only partially revealed. Some studies indicate a close relationship. Here, eight strains of L. aethiopica were characterized genetically and compared with 156 strains of L. tropica from most of the latter species' geographical range to discern the closeness. Twelve unlinked microsatellite markers previously used to genotype strains of L. tropica were successfully applied to the eight strains of L. aethiopica and their microsatellite profiles were compared to those of 156 strains of L. tropica from various geographical locations that were isolated from human cases of cutaneous and visceral leishmaniasis, hyraxes and sand fly vectors. All the microsatellite profiles were subjected to various analytical algorithms: Bayesian statistics, distance-based and factorial correspondence analysis, revealing: (i) the species L. aethiopica, though geographically restricted, is genetically very heterogeneous; (ii) the strains of L. aethiopica formed a distinct genetic cluster; and (iii) strains of L. aethiopica are closely related to strains of L. tropica and more so to the African ones, although, by factorial correspondence analysis, clearly separate from them. The successful application of the 12 microsatellite markers, originally considered species-specific for the species L. tropica, to strains of L. aethiopica confirmed the close relationship between these two species. The Bayesian and distance-based methods clustered the strains of L. aethiopica among African strains of L. tropica, while the factorial correspondence analysis indicated a clear separation between the two species. There was no correlation between

  12. Seroprevalence rates of antibodies against Leishmania infantum and other protozoan and rickettsial parasites in dogs Soroprevalência de anticorpos contra Leishmania infantum e outras espécies de protozoários e rickettsia em cães

    Directory of Open Access Journals (Sweden)

    Silvana de Cássia Paulan

    2013-03-01

    Full Text Available Canine visceral leishmaniasis (CVL is caused by the protozoan Leishmania infantum, which infects dogs and humans in many regions of Brazil. The present study involved an indirect fluorescent antibody test (IFAT to analyze L. infantum, Ehrlichia spp., Babesia canis, Toxoplasma gondii and Neospora caninum infection rates in serum samples from 93 dogs in a rural settlement in Ilha Solteira, SP, Brazil. The seroprevalence rates of anti-L. infantum, anti-Ehrlichia, anti-B. canis, anti-T. gondii and anti-N. caninum antibodies were 37.6%, 75.3%, 72%, 47.3% and 6.4%, respectively. In addition to IFAT, direct microscopic examination of popliteal lymph node aspirates revealed 26.9% of CVL positive dogs. Serological tests revealed that 17.2% of the dogs were seropositive for a single parasite, 29% for two parasites, 33% for three, 16.1% for four, and 1.1% for five parasites, while 3.2% were seronegative for five parasites. The presence of antibodies against these parasites in serum samples from dogs confirmed their exposure to these parasites in this rural area. Because of the potential zoonotic risk of these diseases, mainly leishmaniasis, ehrlichiosis and toxoplasmosis, special attention should focus on programs for the improvement of diagnostic assays and control measures against these parasites.Leishmaniose Visceral Canina (LVC é causada pelo protozoário Leishmania infantum, podendo infectar cães e humanos em várias regiões do Brasil. O presente estudo teve por objetivo realizar a reação de imunofluorescência indireta (RIFI para analisar os índices de infecção parasitária para L. infantum, Ehrlichia spp., Babesia canis, Toxoplasma gondii e Neospora caninum, em 93 amostras de soro de cães de um assentamento rural no município de Ilha Solteira, SP, Brasil. A taxa de soroprevalência de cães com anticorpos anti-L. infantum, anti-Ehrlichia, anti-B. canis, anti-T. gondii e anti-N. caninum foi de 37,6%, 75,3%, 72%, 47,3% e 6

  13. Indigenous Plasmodium ovale malaria in Bangladesh.

    Science.gov (United States)

    Fuehrer, Hans-Peter; Starzengruber, Peter; Swoboda, Paul; Khan, Wasif Ali; Matt, Julia; Ley, Benedikt; Thriemer, Kamala; Haque, Rashidul; Yunus, Emran Bin; Hossain, Shah Monir; Walochnik, Julia; Noedl, Harald

    2010-07-01

    In spite of the high prevalence of malaria in Southeastern Bangladesh, there remains a significant shortage of information regarding the presence of three of five human malaria parasites: Plasmodium ovale, P. malariae, and P. knowlesi. The presence of P. ovale and P. knowlesi has previously never been reported from Bangladesh. We used a genus- and species-specific nested polymerase chain reaction, targeting highly conserved regions of the small subunit ribosomal RNA (SSU rRNA) gene, to investigate the presence of malaria parasites in a total number of 379 patient samples in a survey of patients with febrile illnesses in the Chittagong Hill Tracts in Southeastern Bangladesh. We identified the first cases of P. ovale in Bangladesh. They were confirmed by sequence analysis; 189 of 379 samples (49.9%; 95% confidence interval = 44.9-54.9%) were positive for Plasmodium sp. by PCR. P. falciparum monoinfections accounted for 68.3% (61.3-74.5%), followed by P. vivax (15.3%; 10.9-21.2%), P. malariae (1.6%; 0.5-4.6%), P. ovale (1.6%; 0.5-4.6%), and mixed infections (13.2%; 9.1-18.8%). We found no evidence of P. knowlesi in this region.

  14. Human Infections and Detection of Plasmodium knowlesi

    Science.gov (United States)

    Daneshvar, Cyrus

    2013-01-01

    SUMMARY Plasmodium knowlesi is a malaria parasite that is found in nature in long-tailed and pig-tailed macaques. Naturally acquired human infections were thought to be extremely rare until a large focus of human infections was reported in 2004 in Sarawak, Malaysian Borneo. Human infections have since been described throughout Southeast Asia, and P. knowlesi is now recognized as the fifth species of Plasmodium causing malaria in humans. The molecular, entomological, and epidemiological data indicate that human infections with P. knowlesi are not newly emergent and that knowlesi malaria is primarily a zoonosis. Human infections were undiagnosed until molecular detection methods that could distinguish P. knowlesi from the morphologically similar human malaria parasite P. malariae became available. P. knowlesi infections cause a spectrum of disease and are potentially fatal, but if detected early enough, infections in humans are readily treatable. In this review on knowlesi malaria, we describe the early studies on P. knowlesi and focus on the epidemiology, diagnosis, clinical aspects, and treatment of knowlesi malaria. We also discuss the gaps in our knowledge and the challenges that lie ahead in studying the epidemiology and pathogenesis of knowlesi malaria and in the prevention and control of this zoonotic infection. PMID:23554413

  15. Hyposplenism revealed by Plasmodium malariae infection.

    Science.gov (United States)

    Hommel, Benjamin; Galloula, Alexandre; Simon, Anne; Buffet, Pierre

    2013-08-02

    Hyposplenism, due to splenectomy, inherited red blood cell disorders or acquired conditions such as celiac disease, has an important impact on the severity of malaria, especially in non-immune patients. Conversely, that malaria may reveal functional hyposplenism has not been described previously. A 31-year old gardener was diagnosed with an uncomplicated attack of Plasmodium malariae 11 years after leaving the endemic area. In addition to trophozoites and schizonts, thick and thin smears also showed Howell-Jolly bodies, pointing to functional hyposplenism. This was later confirmed by the presence of a calcified spleen in the context of S/β + sickle-cell syndrome in a patient previously unaware of this condition. Malaria may reveal hyposplenism. Although Howell-Jolly bodies are morphologically similar to nuclei of young Plasmodium trophozoite, distinction on smears is based on the absence of cytoplasm and irregular size of Howell-Jolly bodies. In the patient reported here, hyposplenism was revealed by the occurrence of P. malariae infection relatively late in life. Timely diagnosis of hyposplenism resulted in the implementation of appropriate measures to prevent overwhelming infection with capsulated bacteria. This observation highlights the importance of diagnosing hyposplenism in patients with malaria despite the morphological similarities between ring nuclei and Howell-Jolly bodies on thick smears.

  16. Plasmodium vivax malaria during pregnancy, Bolivia.

    Science.gov (United States)

    Brutus, Laurent; Santalla, José; Schneider, Dominique; Avila, Juan Carlos; Deloron, Philippe

    2013-10-01

    Plasmodium vivax is a major cause of illness in areas with low transmission of malaria in Latin America, Asia, and the Horn of Africa. However, pregnancy-associated malaria remains poorly characterized in such areas. Using a hospital-based survey of women giving birth and an antenatal survey, we assessed the prevalence rates of Plasmodium spp. infections in pregnant women in Bolivia, and evaluated the consequences of malaria during pregnancy on the health of mothers and newborns. P. vivax infection was detected in 7.9% of pregnant women attending antenatal visits, and placental infection occurred in 2.8% of deliveries; these rates did not vary with parity. Forty-two percent of all P. vivax malaria episodes were symptomatic. P. vivax-infected pregnant women were frequently anemic (6.5%) and delivered babies of reduced birthweight. P. vivax infections during pregnancy are clearly associated with serious adverse outcomes and should be considered in prevention strategies of pregnancy-associated malaria.

  17. Leishmania (Viannia braziliensis em cães naturalmente infectados Leishmania (Viannia braziliensis in naturally infected dogs

    Directory of Open Access Journals (Sweden)

    Maria de Fátima Madeira

    2003-10-01

    Full Text Available Foram estudados oito cães provenientes do Município de Maricá (RJ, com lesões sugestivas de leishmaniose tegumentar americana por métodos parasitológicos e sorológicos. Leishmania spp foi encontrada em seis cães através do cultivo in vitro. Anticorpos específicos foram detectados em seis animais pelo ELISA e em dois pela imunofluorescência indireta. Cinco isolados caninos analisados apresentaram zimodema similar a Leishmania (Viannia braziliensis. Sugere-se que cães clinicamente suspeitos sejam acompanhados periodicamente, na tentativa de confirmar o diagnóstico da leishmaniose tegumentar canina.Eight dogs from Maricá Municipality (RJ, with suggestive lesion of american tegumentary leishmaniasis were studied by parasitological and serological methods. Leishmania spp was found in six dogs by in vitro cultivation. Specific antibodies were detected in six dogs by ELISA and in two by indirect immunofluorescence. Five canine isolates were found to belong to the same zymodeme as Leishmania (Viannia braziliensis. The authors suggest that clinically suspect dogs should be followed-up in an attempt to confirm the diagnostic of canine tegumentary leishmaniasis.

  18. Regulator and effector functions of T-cell subsets in human Leishmania infections

    DEFF Research Database (Denmark)

    Kemp, M

    1997-01-01

    the cytokine production by CD4+ T cells has been identified as a major factor in determining the outcome of the infection. In these models Th1 cells producing IFN-gamma provide protection against the infection whereas Th2 cells producing IL-4 and IL-10 aggravate the disease. The fatal outcome of Leishmania...... reactions to Leishmania parasites in humans can be associated with both protection and pathogenesis. Many individuals without previous exposure to Leishmania parasites have T cells which can respond to Leishmania antigens. These cells have the potential to generate either Th1 or Th2 like responses. During...... infection with Leishmania parasites humans develop specific T-cell recognition of well-characterized parasite antigens. T cells producing disease-exacerbating factors such as IL-4 in response to Leishmania antigen stimulation have been identified in humans as well as in mice. Both Th1 like and Th2 like...

  19. Plasmodium falciparum full life cycle and Plasmodium ovale liver stages in humanized mice.

    Science.gov (United States)

    Soulard, Valérie; Bosson-Vanga, Henriette; Lorthiois, Audrey; Roucher, Clémentine; Franetich, Jean-François; Zanghi, Gigliola; Bordessoulles, Mallaury; Tefit, Maurel; Thellier, Marc; Morosan, Serban; Le Naour, Gilles; Capron, Frédérique; Suemizu, Hiroshi; Snounou, Georges; Moreno-Sabater, Alicia; Mazier, Dominique

    2015-07-24

    Experimental studies of Plasmodium parasites that infect humans are restricted by their host specificity. Humanized mice offer a means to overcome this and further provide the opportunity to observe the parasites in vivo. Here we improve on previous protocols to achieve efficient double engraftment of TK-NOG mice by human primary hepatocytes and red blood cells. Thus, we obtain the complete hepatic development of P. falciparum, the transition to the erythrocytic stages, their subsequent multiplication, and the appearance of mature gametocytes over an extended period of observation. Furthermore, using sporozoites derived from two P. ovale-infected patients, we show that human hepatocytes engrafted in TK-NOG mice sustain maturation of the liver stages, and the presence of late-developing schizonts indicate the eventual activation of quiescent parasites. Thus, TK-NOG mice are highly suited for in vivo observations on the Plasmodium species of humans.

  20. Identification of a Highly Antigenic Region of Subtilisin-Like Serine Protease 1 for Serodiagnosis of Neospora caninum Infection

    Science.gov (United States)

    Ybañez, Rochelle Haidee D.; Terkawi, Mohamad Alaa; Kameyama, Kyohko; Xuan, Xuenan

    2013-01-01

    Neospora caninum is an apicomplexan parasite that causes abortion in cattle; hence, accurate diagnosis of this pathogen is important to the cattle farming industry. Our previous proteomics and immunoscreening analyses revealed that the N. caninum subtilisin-like serine protease 1 (NcSUB1) has potential as a serodiagnostic tool for Neospora. Consequently, we expressed two fragments containing five NcSUB1 tandem repeat copies covering amino acids (aa) 524 to 843 (NcSUB1t) and 555 to 679 (NcSUB1tr) to identify the antigenic regions. The serodiagnostic performances of NcSUB1t and NcSUB1tr were compared with that of N54, which contains a single copy of the repeats (aa 649 to 784), and with the truncated NcSAG1 (NcSAG1t), which lacks a signal peptide and C-terminal hydrophobic regions, as a positive reference. Serum samples from N. caninum experimentally infected cattle and mice and cattle from a farm with confirmed cases of Neospora abortion were tested by enzyme-linked immunosorbent assay (ELISA) with the four antigens. In the N. caninum experimentally infected cattle, the highest IgG1 antibody titers were detected against NcSUB1t, while specific IgG1 antibodies were detectable from 16 days postinfection (dpi), with levels peaking at 36 dpi for all of the antigens. On the other hand, the levels of anti-NcSUB1 IgG2 antibodies were lower than those of anti-SAG1t IgG2 antibodies. The ELISA with NcSUB1t and NcSUB1tr had good sensitivity (94.59 to 95.95%) and specificity (80 to 100%) with bovine serum field samples compared to NcSAG1t and showed no cross-reactions with sera from Toxoplasma gondii experimentally infected mice. Moreover, IgG antibodies against NcSUB1t were detected during parturition in the NcSAG1t antibody-positive cattle, and NcSUB1t-specific antibody transfer was observed from a mother to her calf. Our results show that the NcSUB1 tandem repeat is potentially useful for serodiagnosis of N. caninum. PMID:23966554

  1. Effects of crossbreeding on endocrine patterns determined in pregnant beef/dairy cows naturally infected with Neospora caninum.

    Science.gov (United States)

    García-Ispierto, I; Serrano-Pérez, B; Almería, S; Martínez-Bello, D; Tchimbou, A F; de Sousa, N M; Beckers, J F; López-Gatius, F

    2015-03-01

    Neospora caninum is an intracellular coccidian parasite causing abortion worldwide in dairy cattle. Studies have shown that N caninum infection modifies endocrine patterns and that beef cows or cows with a crossbreed pregnancy, especially for a greater maternal-paternal genetic distance, show a reduced risk of abortion when naturally infected compared with pure-breed Holstein Friesian (HF) pregnancies. This study examined the effects of crossbreeding on plasma progesterone (P4), pregnancy-associated glycoprotein (PAG)-1 and -2, and prolactin patterns produced during gestation in N caninum-infected beef/dairy cows. We analyzed 74 pregnancies in nonaborting cows carrying a single fetus established in 26 lactating HF cows bred with Holstein bulls (H-H), 13 HF cows bred with Limousin bulls (H-L), 12 HF cows used as recipients of transferred in vivo-produced frozen-thawed Rubia Gallega (beef breed; RG) embryos (H-RG-ET), and 23 RG suckling cows bred with RG bulls (RG-RG). Of the cows, 29 (39%) were seropositive for N caninum. Blood samples for hormone and placental protein determinations were collected on Days 30, 60, 90, 120, 150, and 180 of gestation. Procedures of repeated measures analysis of variance throughout gestation revealed higher PAG-1 levels in the H-L and H-RG-ET groups compared with H-H and RG-RG. Higher prolactin levels were detected in RG-RG than in the remaining groups. N caninum seropositivity and fetal genotype had a significant effect on PAG-2 concentrations, such that highest levels of PAG-2 occurred in RG-RG seropositive cows and lowest in H-H seropositive cows, whereas Neospora-seropositive cows showed lower P4 concentrations than their seronegative partners. In conclusion, chronic N caninum infection modifies endocrine patterns of PAG-2 and P4 during pregnancy, whereas PAG-1 and prolactin concentrations are affected by breed and fetal genotype, irrespective of Neospora infection status. Copyright © 2015 Elsevier Inc. All rights reserved.

  2. Effect of Kelussia odoratissima Mozaff essential oil on promastigot form of Leishmania major (in vitro)

    OpenAIRE

    Pirali Kheirabadi Khodadad; Saei Dehkordi Siavash; Kheibari Parviz

    2015-01-01

    Introduction: Leishmaniasis is a zoonotic disease caused by a protozoan of the genus Leishmania. In this study, the effects of Kelussia odoratissima Mozaff essential oil on the promastigot form of Leishmania major were studied. Methods: In this study, the effects of Kelussia odoratissima Mozaff essential oil on the promastigot form of Leishmania major were assessed by calculating the average number of surviving promastigots after exposure to different concentrations of essential oil, relativ...

  3. RISK FACTORS ASSOCIATED TO Neospora caninum INFECTION IN DAIRY COWS IN PERNAMBUCO FATORES DE RISCOS ASSOCIADOS À INFECÇÃO POR Neospora caninum EM MATRIZES BOVINAS LEITEIRAS EM PERNAMBUCO

    Directory of Open Access Journals (Sweden)

    Silvana Suely de Assis Rabelo

    2008-07-01

    Full Text Available The aim of the present work was to evaluate the risk factors associated to Neospora caninum in dairy cows in the state of Pernambuco. Were collected 469 blood samples originated from 20 different farms. Indirect Immunofluorescence (IFI was the technique employed to detect N. caninum antibodies in the samples. During sample collection, epidemiological inquiring was performed. From the samples tested, 31.7% (163/469 showed a positive reaction to N. caninum, distributed among 17 (85% of the properties studied. It was observed a significant association with all aspects related to hygienic-sanitary management such as veterinary assistance (p = 0.011; nutritional condition (p = 0.031; presence of wetlands (p < 0.001; manipulation of newborn calves (p < 0.001 and the fate of the cows had aborted (p = 0.004. Moreover, risk factors associated to reproductive disturb such as abortion history (p = 0.042 and abortions period (p = 0.014, were also observed. The findings described in this study characterize the first evidence of N. caninum infection in dairy cows in the state of Pernambuco, demonstrating the necessity of performing systematic diagnosis and monitoring of the cattle regarding their reproductive efficiency, in addition to the implementation of prophylactic and control measures.

     

    KEY WORDS: Cattle, epidemiologic aspects, indirect immunofluorescence, Neospora caninum.

     

    Objetivou-se com este trabalho avaliar os fatores de riscos associados à infecção pelo Neospora caninum em matrizes bovinas leiteiras no Estado de Pernambuco. Colheram-se 469 amostras de sangue, distribuídas em vinte propriedades. A técnica utilizada para detecção de anticorpos contra N. caninum foi a

  4. A nationwide survey on seroprevalence of Neospora caninum infection in beef cattle in Uruguay.

    Science.gov (United States)

    Bañales, Pedro; Fernandez, Leandro; Repiso, María V; Gil, Andres; Dargatz, David A; Osawa, Takeshi

    2006-06-30

    Bovine abortions due to Neospora caninum infection have been reported worldwide and its economic impact on the beef industry has been acknowledged as a problem. Uruguay has the largest export value of beef per acre in South America. However, no data on the prevalence of N. caninum infection have been available in this country. The objective of this study was to estimate the prevalence and distribution of N. caninum infection in beef cattle in Uruguay through a nationwide survey. A two stage sampling design was used with farms being selected in stage one and animals being selected in stage two. A brief questionnaire was administered on each farm. Seroprevalence of N. caninum in 4444 beef cattle from 229 farms in all the counties, except Montevideo, of Uruguay was determined by an ELISA. The data were then analyzed to identify associations between infection and variables such as type of animal (cow or heifer), herd size, use of veterinary advice, productivity of the soil in relation to the national average, use of improved grass, use of mineral salts, use of supplemental feed, and presence of a dog(s) on the farm. The estimated proportion of positive farms for all the beef cattle operations was 69.2% (95% confidence interval [CI], 53.7-84.7). The overall cattle seroprevalence was estimated as 13.9% (95% CI, 11.6-16.3). The prevalence estimation by animal category was 14.3% (95% CI, 11.4-17.2) for beef cows and 12.9% (95% CI, 10.0-15.8) for beef heifers. There was no significant difference in the estimated prevalence between the two animal types. There was no significant difference in the animal level prevalence of N. caninum infection among different herd sizes. None of the herd demographic or management variables was significantly associated with the seropositivity to N. caninum infection. In conclusion, these results show that N. caninum infection is common among beef herds across Uruguay. Since the beef industry is one of the key industries in Uruguay, the

  5. Effects of Neospora caninum infection on brain microvascular endothelial cells bioenergetics

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    Elsheikha Hany M

    2013-01-01

    Full Text Available Abstract Background The brain is the most commonly affected organ during Neospora caninum infection but the mechanisms utilized by this protozoan parasite for traversal of the blood–brain barrier (BBB are not yet understood. Herein, we investigate the cellular pathogenicity of N. caninum infection on bioenergetics of human brain microvascular endothelial cells (HBMECs, a fundamental component of the BBB. Methods We tracked the growth kinetics of N. caninum in HBMECs. Focusing on cell bioenergetics, oxygen consumption rate (OCR was determined using Clark electrode system and mitochondrial membrane potential (ΔΨm was evaluated using DePsipher staining by fluorescence microscopy in the presence and absence of infection. Results HBMECs provided a receptive environment for parasite proliferation. N. caninum tachyzoites were able to invade and replicate within HBMECs without significantly altering cell proliferation rate, as measured with the MTT assay, up to 24 hr post infection (pi. The oxygen consumption rate (OCR was significantly inhibited (p 6 cell min-1 and from −0.29±0.09 to −0.16±0.1 nmol 106 cell min-1 for uninfected HBMECs and free N. Caninum tachyzoites, respectively]. After normalization for DNA content the basal OCR did not differ between two host cell types: HBMECs and K562. The OCR of HBMECs was significantly elevated 24 hr pi in the absence of substrate, in 10 mM glucose and in the presence of a tetramethyl-p-phenylenediamine (TMPD/ascorbate redox shuttle. Although quantitatively similar results were observed for uninfected K562 cells, there was no effect on their OCR 24 hr pi with N. caninum under any of the above substrate conditions. 6mM azide abolished OCR in all situations. Mitochondrial staining with DePsipher indicated no change in their membrane potential (Δψm up to 24 hr pi. Conclusions N. caninum is able to grow in HBMECs without markedly disrupting their normal proliferation or mitochondrial integrity. However

  6. Can hierarchical modeling improve our understanding of bovine abortion due to Neospora caninum infection?

    Science.gov (United States)

    Martinez, Brayan Alexander Fonseca; Leotti, Vanessa Bielefeldt; Borba, Mauro Riegert; Silva, Gustavo de Sousa E; Corbellini, Luís Gustavo

    2017-04-15

    The purpose of this study was to use mixed logistic regression to evaluate the association between Neospora caninum serostatus and abortion, accounting for the effects of farms. The main objective was to explore the interpretation of this model and discuss the contribution of this analysis to our understanding of the disease's epidemiology. A mixed-effects logistic model using farms as a random effect and the serostatus for N. caninum, age of cattle and farm location as fixed effects was performed. The data from 1256 cows over 15 months of age from 60 farms were used, and the abortion information was obtained from farm records. A significant association between N. caninum serostatus and abortion was found (p<0.0001). Seropositive cows had 6.63 times greater odds of having a history of previous abortion (95% CI: 4.35-13.37). There was remarkable variability across farms in the probability of a cow having a history of an abortion. Including the effects of the farms in the regression, it was possible to estimate an intraclass correlation coefficient (ICC) of 16%. That means that 16% of the variation in abortion occurrence that was not explained by the fixed effects was due to farms. In practical terms, this variation means that while there are farms with several seropositive cows and no/few abortion cases, the opposite is also true, with a high number of abortions in farms with low/medium seroprevalence. The remaining variability (84%) was not explained by the effect of N. caninum, age, region, and the effect of farms, i.e., it is due to unknown factors that are causing abortions. The results of this study reinforce the importance of N. caninum as a cause of abortions and demonstrate the significant heterogeneity in the probability of a cow having a history of an abortion that cannot be explained completely by N. caninum serostatus, age or location. Including the hierarchical structure of the population along with correct interpretation of the model estimates helps us

  7. Neospora caninum tachyzoite immunome study reveals differences among three biologically different isolates.

    Science.gov (United States)

    Regidor-Cerrillo, Javier; García-Lunar, Paula; Pastor-Fernández, Iván; Álvarez-García, Gema; Collantes-Fernández, Esther; Gómez-Bautista, Mercedes; Ortega-Mora, Luis M

    2015-09-15

    Pathogenesis of bovine neosporosis is determined by different host- and parasite-dependent factors, including isolate virulence. A previous study identified that several Neospora caninum tachyzoite proteins were more abundant in virulent isolates, Nc-Liv and Nc-Spain7, compared with the low-virulent isolate Nc-Spain1H. Herein, we explored differences in the immunomes of these three isolates. Protein extracts from the Nc-Liv, Nc-Spain1H and Nc-Spain7 isolates were analysed in a 3×3 design by 2-DE immunoblot using sera from experimentally infected mice with these same three isolates. All isolates displayed a highly similar antigenic pattern when they were assessed using the same serum. Most of the reactive spots were located in the acidic region (pH 3-7) and grouped in 3 antigenic areas (250-70, 45-37 and 35-15 KDa). Differences found in the immunome depended on the sera used, regardless of the extract employed. In this sense, sera from Nc-Liv and Nc-Spain7 infected mice recognized the highest number of antigens, followed by Nc-Spain1H infected mice sera. In fact, 4 proteins identified by MS were not consistently detected in each isolate extract by sera from low-virulent Nc-Spain1H-infected mice: serine-threonine phosphatase 2C and superoxide dismutase (related to metabolism), gliding associated protein GAP45 (related to tachyzoites invasion), and NcGRA1 (located on dense granules). Similarly, 4 non-identified spots and another 2 spots chains located in 45-37 kDa area were not detected by this pooled sera. Variations between virulent Nc-Spain7 and Nc-Liv were limited to the absence of recognition by sera from Nc-Spain7-infected mice of GAP45 and the spot chains located in the 45-37 kDa area. These results suggest that variations in the immunome profiles rely on the immune response induced by each isolate and that these differentially recognized antigens could be investigated as putative virulence markers of neosporosis. Copyright © 2015 Elsevier B.V. All rights

  8. Identificação de espécies de Leishmania isoladas de casos humanos em Mato Grosso do Sul por meio da reação em cadeia da polimerase Identification of Leishmania species isolated in human cases in Mato Grosso do Sul, by means of the polymerase chain reaction

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    Manoel Sebastião da Costa Lima Junior

    2009-06-01

    Full Text Available As leishmanioses são zoonoses endêmicas em Mato Grosso do Sul e têm por agentes etiológicos nessa região Leishmania (Leishmania chagasi, Leishmania (Leishmania amazonensis e Leishmania (Viannia braziliensis. Como método para identificação de espécies de Leishmania, a reação em cadeia da polimerase é uma ferramenta com elevada especificidade e sensibilidade. Analisaram-se 39 isolados de Leishmania criopreservados, obtidos por meio de aspirado medular e/ou biópsia de lesão, conforme a suspeita clínica. Os isolados foram submetidos à extração de DNA e à reação em cadeia da polimerase com os iniciadores: RV1/RV2 para Leishmania (Leishmania chagasi, a1/a2 para a identificação de Leishmania (Leishmania amazonensis e b1/b2 para Leishmania (Viannia braziliensis. Leishmania (Leishmania chagasi foi a única espécie identificada em 37 casos de leishmaniose visceral. Leishmania (Leishmania amazonensis foi identificada em dois isolados de pacientes com diagnóstico de leishmaniose tegumentar. Os resultados obtidos confirmam a possibilidade do uso dos três pares de iniciadores como uma ferramenta na caracterização de isolados de Leishmania.Leishmaniases are endemic zoonoses in the State of Mato Grosso do Sul. Their etiological agents in this region of Brazil are Leishmania (Leishmania chagasi, Leishmania (Leishmania amazonensis and Leishmania (Viannia braziliensis. The polymerase chain reaction (PCR is a tool with high specificity and sensitivity for identifying Leishmania species. This study examined 39 cryopreserved isolates of Leishmania that had been collected by bone marrow aspiration and/or lesion biopsy, depending on the clinical suspicion. The isolates were subjected to DNA extraction and PCR using the following primers: RV1/RV2 for identifying Leishmania (Leishmania chagasi, a1/a2 for Leishmania (Leishmania amazonensis and b1/b2 for Leishmania (Viannia braziliensis.Leishmania (Leishmania chagasi was the only species

  9. Quantification of vertical transmission of Neospora caninum in dairy cows in Minas Gerais, Brazil Quantificação da transmissão vertical de Neospora caninum em vacas leiteiras de Minas Gerais, Brasil

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    Raquel Ribeiro Dias Santos

    2012-09-01

    Full Text Available The objective of this cross-sectional study was to estimate the rate of vertical transmission and to investigate horizontal transmission of Neospora caninum and occurrences of reproductive abnormalities in seropositive dairy cows on two farms in the state of Minas Gerais, Brazil. The frequency of cows seropositive for N.caninum according to the indirect fluorescent antibody test (IFAT was 39.4% (93/236 for Farm A and 31.4% (32/102 for the Farm B (p > 0.05. The mean vertical transmission rates for N. caninum were 29% and 9% for the herds of Farms A and B, respectively. No negative effects (p > 0.05 from infection by N.caninum were observed regarding milk production and occurrences of reproductive abnormalities in herds A and B.O objetivo deste estudo transversal foi estimar a taxa de transmissão vertical e investigar a transmissão horizontal de Neospora caninum, e a ocorrência de alterações reprodutivas em vacas leiteiras soropositivas em duas fazendas no Estado de Minas Gerais, Brasil. A frequência de vacas soropositivas a N. caninum pelo teste de imunofluorescência indireta (RIFI foi de 39,4% (93/236 e 31,4% (32/102 para as fazendas A e B, respectivamente. A taxa média de transmissão vertical de N. caninum, respectivamente, foi de 29% e 9% para os rebanhos A e B. Não foi observado nenhum efeito negativo (p > 0,05 da infecção por N. caninum sobre a produção de leite e a ocorrência de alterações reprodutivas nos rebanhos A e B.

  10. Impact of Plasmodium falciparum and hookworm infections on the ...

    African Journals Online (AJOL)

    abp

    2013-01-18

    Saharan Africa and they increase the prevalence of anaemia in pregnancy with resultant poor pregnancy outcomes. This study was carried out to assess the impact of Plasmodium falciparum and hookworm infections on.

  11. Anti-Plasmodium activity of ceramide analogs

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    Gatt Shimon

    2004-12-01

    Full Text Available Abstract Background Sphingolipids are key molecules regulating many essential functions in eukaryotic cells and ceramide plays a central role in sphingolipid metabolism. A sphingolipid metabolism occurs in the intraerythrocytic stages of Plasmodium falciparum and is associated with essential biological processes. It constitutes an attractive and potential target for the development of new antimalarial drugs. Methods The anti-Plasmodium activity of a series of ceramide analogs containing different linkages (amide, methylene or thiourea linkages between the fatty acid part of ceramide and the sphingoid core was investigated in culture and compared to the sphingolipid analog PPMP (d,1-threo-1-phenyl-2-palmitoylamino-3-morpholino-1-propanol. This analog is known to inhibit the parasite sphingomyelin synthase activity and block parasite development by preventing the formation of the tubovesicular network that extends from the parasitophorous vacuole to the red cell membrane and delivers essential extracellular nutrients to the parasite. Results Analogs containing methylene linkage showed a considerably higher anti-Plasmodium activity (IC50 in the low nanomolar range than PPMP and their counterparts with a natural amide linkage (IC50 in the micromolar range. The methylene analogs blocked irreversibly P. falciparum development leading to parasite eradication in contrast to PPMP whose effect is cytostatic. A high sensitivity of action towards the parasite was observed when compared to their effect on the human MRC-5 cell growth. The toxicity towards parasites did not correlate with the inhibition by methylene analogs of the parasite sphingomyelin synthase activity and the tubovesicular network formation, indicating that this enzyme is not their primary target. Conclusions It has been shown that ceramide analogs were potent inhibitors of P. falciparum growth in culture. Interestingly, the nature of the linkage between the fatty acid part and the

  12. Single-Step Multiplex PCR Assay for Characterization of New World Leishmania Complexes

    Science.gov (United States)

    Harris, Eva; Kropp, Gerald; Belli, Alejandro; Rodriguez, Betzabé; Agabian, Nina

    1998-01-01

    We have developed a PCR assay for one-step differentiation of the three complexes of New World Leishmania (Leishmania braziliensis, Leishmania mexicana, and Leishmania donovani). This multiplex assay is targeted to the spliced leader RNA (mini-exon) gene repeats of these organisms and can detect all three complexes simultaneously, generating differently sized products for each complex. The assay is specific to the Leishmania genus and does not recognize related kinetoplastid protozoa, such as Trypanosoma cruzi, Trypanosoma brucei, and Crithidia fasciculata. It correctly identified Leishmania species with a broad geographic distribution in Central and South America. The sensitivity of the PCR amplification ranged from 1 fg to 10 pg of DNA (0.01 to 100 parasites), depending on the complex detected. Crude extracts of cultured parasites, prepared simply by boiling diluted cultures, served as excellent templates for amplification. Crude preparations of clinical material were also tested. The assay detected L. braziliensis in dermal scrapings from cutaneous leishmanial lesions, Leishmania chagasi in dermal scrapings of atypical cutaneous leishmaniasis, and L. mexicana from lesion aspirates from infected hamsters. We have minimized the material requirements and maximized the simplicity, rapidity, and informative content of this assay to render it suitable for use in laboratories in countries where leishmaniasis is endemic. This assay should be useful for rapid in-country identification of Leishmania parasites, particularly where different Leishmania complexes are found in the same geographical area. PMID:9650950

  13. Pesquisa de anticorpos anti-Neospora spp. e anti-herpersvírus equino em cavalos de tração no município de Santa Maria, RS, Brasil Looking for antibodies anti-Neospora spp. and anti-equine herpersvirus in carter horses in Santa Maria, Brazil

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    Luís Antonio Sangioni

    2011-02-01

    Full Text Available O presente estudo teve como objetivo investigar a ocorrência de anticorpos contra Neospora spp. e o herpesvírus equino (EHV em soros de cavalos de tração de Santa Maria, RS, Brasil. Os soros sanguineos provenientes de 91 animais do projeto de extensão da Universidade Federal de Santa Maria "Programa de Ação Social Amigos do Carroceiro" (PASAC foram colhidos no período de março de 2006 a maio de 2008 e submetidos ao teste de imunofluorescência indireta para detecção de anticorpos anti-Neospora spp. e à técnica de soro neutralização para anticorpos anti-EHV. Constatou-se que 15,4% (14/91 das amostras foram reagentes para o Neospora spp. e não se verificou a presença da infecção pelo herpesvírus equino. Sugere-se a circulação do coccídeo na população equina estudada. Salienta-se a necessidade de estudos adicionais sobre o potencial risco zoonótico e a importância sanitária desse protozoário nos cavalos de tração.This study aimed to investigate the prevalence of antibodies against Neospora spp and equine herpesvirus (EHV among carter horses in Santa Maria, RS, Brazil. Serum samples from 91 horses, involved in the extension project "Programa de Ação Social Amigo do Carroceiro" at Universidade Federal de Santa Maria, were collected from March of 2006 to May of 2008. Immunofluorescence assay was used to detect Neospora spp. and virus neutralization assay to EHV. This research showed 15.4% (14/91 samples were positive to Neospora spp. and no antibodies against EHV were detected. These results suggest the presence of Neospora spp. in carter horses of Santa Maria. Additional studies are needed to determine the zoonotic potential risk and the sanitary importance this protozoan in the population analyzed.

  14. Reproductive implications of exposure to Toxoplasma gondii and Neospora caninum in western grey kangaroos (Macropus fuliginosus ocydromus).

    Science.gov (United States)

    Mayberry, Chris; Maloney, Shane K; Mitchell, Jeff; Mawson, Peter R; Bencini, Roberta

    2014-04-01

    Australian marsupials are thought to be particularly vulnerable to pathologic impacts of Toxoplasma gondii, and they may be similarly affected by Neospora caninum. Pathology due to either organism could be expressed as reduced female reproductive performance. We studied adult female western grey kangaroos (Macropus fuliginosus ocydromus) from suburban Perth, Western Australia, between May 2006 and October 2008. We used indirect fluorescent antibody tests to look for evidence of exposure to T. gondii and N. caninum in M. fuliginosus ocydromus and tested the association between their reproductive performance and a positive test result. Although 20% of plasma samples collected from 102 female kangaroos were positive for T. gondii and 18% were positive for N. caninum, we found no association between positive results and reproductive performance. Further study will be required to clarify if, and under what circumstances, T. gondii and N. caninum are pathogenic to macropod marsupials.

  15. Identification and discrimination of Toxoplasma gondii, Sarcocystis spp., Neospora spp., and Cryptosporidium spp. by righ-resolution melting analysis.

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    Hllytchaikra Ferraz Fehlberg

    Full Text Available The objective of this study was to standardize the high-resolution melting method for identification and discrimination of Toxoplasma gondii, Sarcocystis spp., Neospora spp., and Cryptosporidium spp. by amplification of 18S ribosomal DNA (rDNA using a single primer pair. The analyses were performed on individual reactions (containing DNA from a single species of a protozoan, on duplex reactions (containing DNA from two species of protozoa in each reaction, and on a multiplex reaction (containing DNA of four parasites in a single reaction. The proposed method allowed us to identify and discriminate the four species by analyzing the derivative, normalized, and difference melting curves, with high reproducibility among and within the experiments, as demonstrated by low coefficients of variation (less than 2.2% and 2.0%, respectively. This is the first study where this method is used for discrimination of these four species of protozoa in a single reaction.

  16. First isolation of Neospora caninum from blood of a naturally infected adult dairy cow in Beijing, China.

    Science.gov (United States)

    Hao, Pan; Yang, Na; Cui, Xia; Liu, Jing; Yang, Daoyu; Liu, Qun

    2014-12-01

    Neospora caninum is an important cause of abortion in cattle worldwide, but the isolation of a viable parasite from an abortus is difficult, and viable N. caninum has not been isolated from any host in China. In the present study, peripheral blood samples were collected from a jugular vein of an adult dairy cow that had aborted; the cow was seropositive to N. caninum antibodies by ELISA. White blood cells were separated and seeded onto Vero cell monolayer cultures for parasite isolation. Tachyzoites were first observed in cell culture on day 84 after initial inoculation. The parasite was confirmed to be N. caninum by gene sequencing and immunofluorescence, and by bioassays in BALB/c mice. The new N. caninum isolate (NC-Bj) has a unique pattern on microsatellite Cont-14. To our knowledge, this is the first successful isolation of N. caninum in China from any host.

  17. In vitro invasion efficiency and intracellular proliferation rate comprise virulence-related phenotypic traits of Neospora caninum

    Science.gov (United States)

    2011-01-01

    In this study, we examined the in vitro invasion and proliferation capacities of the Nc-Liv and ten Spanish Neospora caninum isolates (Nc-Spain 1 H - Nc-Spain 10). The invasion rate was determined as the number of tachyzoites that completed their internalisation into MARC-145 cells at 2, 4, and 6 h post-inoculation (pi). The proliferation rate was evaluated by determining the doubling time during the exponential proliferation period. Significant differences in the invasion rates of these isolates were detected at 2 and 4 h pi (P 0.62, P < 0.05). The results of this study may help us to explain the differences in the pathogenicity that are displayed by different isolates. PMID:21345202

  18. Identification and discrimination of Toxoplasma gondii, Sarcocystis spp., Neospora spp., and Cryptosporidium spp. by righ-resolution melting analysis.

    Science.gov (United States)

    Fehlberg, Hllytchaikra Ferraz; Maciel, Bianca Mendes; Albuquerque, George Rêgo

    2017-01-01

    The objective of this study was to standardize the high-resolution melting method for identification and discrimination of Toxoplasma gondii, Sarcocystis spp., Neospora spp., and Cryptosporidium spp. by amplification of 18S ribosomal DNA (rDNA) using a single primer pair. The analyses were performed on individual reactions (containing DNA from a single species of a protozoan), on duplex reactions (containing DNA from two species of protozoa in each reaction), and on a multiplex reaction (containing DNA of four parasites in a single reaction). The proposed method allowed us to identify and discriminate the four species by analyzing the derivative, normalized, and difference melting curves, with high reproducibility among and within the experiments, as demonstrated by low coefficients of variation (less than 2.2% and 2.0%, respectively). This is the first study where this method is used for discrimination of these four species of protozoa in a single reaction.

  19. Exposure of free-living jaguars to Toxoplasma gondii, Neospora caninum and Sarcocystis neurona in the Brazilian Pantanal

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    Selma Samiko Miyazaki Onuma

    2014-12-01

    Full Text Available Toxoplasma gondii, Neospora caninum and Sarcocystis neurona are related apicomplexan parasites that cause reproductive and neurological disorders in a wide range of domestic and wild animals. In the present study, the immunofluorescence antibody test (IFAT was used to investigate the presence of antibodies against T. gondii, N. caninum and S. neurona in the sera of 11 free-living jaguars (Panthera onca in two protected areas in the Pantanal region of Mato Grosso state, Brazil. Ten jaguars (90.9% showed seropositivity for T. gondii, eight (72.7% for S. neurona, and seven (63.6% for N. caninum antigens. Our findings reveal exposure of jaguars to these related coccidian parasites and circulation of these pathogens in this wild ecosystem. To the best of our knowledge, this is the first serological detection of N. caninum and S. neurona in free-living jaguars.

  20. Protective effect of intranasal immunization with Neospora caninum membrane antigens against murine neosporosis established through the gastrointestinal tract.

    Science.gov (United States)

    Ferreirinha, Pedro; Dias, Joana; Correia, Alexandra; Pérez-Cabezas, Begoña; Santos, Carlos; Teixeira, Luzia; Ribeiro, Adília; Rocha, António; Vilanova, Manuel

    2014-02-01

    Neospora caninum is an Apicomplexa parasite that in the last two decades was acknowledged as the main pathogenic agent responsible for economic losses in the cattle industry. In the present study, the effectiveness of intranasal immunization with N. caninum membrane antigens plus CpG adjuvant was assessed in a murine model of intragastrically established neosporosis. Immunized mice presented a lower parasitic burden in the brain on infection with 5 × 10(7) tachyzoites, showing that significant protection was achieved by this immunization strategy. Intestinal IgA antibodies raised by immunization markedly agglutinated live N. caninum tachyzoites whereas previous opsonization with IgG antibodies purified from immunized mice sera reduced parasite survival within macrophage cells. Although an IgG1 : IgG2a ratio neosporosis and indicate that parasite-specific mucosal and circulating antibodies have a protective role against this parasitic infection. © 2013 John Wiley & Sons Ltd.

  1. Artificial insemination of cows with semen in vitro contaminated with Neospora caninum tachyzoites failed to induce neosporosis.

    Science.gov (United States)

    Canada, Nuno; Meireles, Carla Sofia; Ferreira, Paulo; Correia da Costa, José Manuel; Rocha, António

    2006-06-30

    Neosporosis is a major cause of abortion in cattle all over the world. Congenital transmission as well as horizontal transmission by ingestion of oocysts has been described. The detection of Neospora caninum DNA in bull semen warrants the investigation of possible transmission through the use of contaminated semen. In this experiment four cows were artificially inseminated with frozen-thawed semen contaminated in vitro with viable N. caninum tachyzoites (group A) and four control cows were inseminated with tachyzoites-free frozen-thawed semen, from the same bull (group B). Serum samples were collected 15 days before the artificial insemination (AI) and at days 10, 14, 21, 28, 45, 60 and 75 post-insemination. All sera samples were tested for neosporosis by direct agglutination test (DAT). Three of the cows from group A had negative DAT titers (neosporosis by artificial insemination with frozen-thawed semen is an unlikely event.

  2. Development of vaccines for Plasmodium vivax malaria.

    Science.gov (United States)

    Mueller, Ivo; Shakri, Ahmad Rushdi; Chitnis, Chetan E

    2015-12-22

    Plasmodium vivax continues to cause significant morbidity outside Africa with more than 50% of malaria cases in many parts of South and South-east Asia, Pacific islands, Central and South America being attributed to P. vivax infections. The unique biology of P. vivax, including its ability to form latent hypnozoites that emerge months to years later to cause blood stage infections, early appearance of gametocytes before clinical symptoms are apparent and a shorter development cycle in the vector makes elimination of P. vivax using standard control tools difficult. The availability of an effective vaccine that provides protection and prevents transmission would be a valuable tool in efforts to eliminate P. vivax. Here, we review the latest developments related to P. vivax malaria vaccines and discuss the challenges as well as directions toward the goal of developing highly efficacious vaccines against P. vivax malaria. Copyright © 2015. Published by Elsevier Ltd.

  3. Rheopathologic Consequence of Plasmodium vivax Rosette Formation.

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    Rou Zhang

    2016-08-01

    Full Text Available Malaria parasites dramatically alter the rheological properties of infected red blood cells. In the case of Plasmodium vivax, the parasite rapidly decreases the shear elastic modulus of the invaded RBC, enabling it to avoid splenic clearance. This study highlights correlation between rosette formation and altered membrane deformability of P. vivax-infected erythrocytes, where the rosette-forming infected erythrocytes are significantly more rigid than their non-rosetting counterparts. The adhesion of normocytes to the PvIRBC is strong (mean binding force of 440pN resulting in stable rosette formation even under high physiological shear flow stress. Rosetting may contribute to the sequestration of PvIRBC schizonts in the host microvasculature or spleen.

  4. Plasmodium falciparum: multifaceted resistance to artemisinins.

    Science.gov (United States)

    Paloque, Lucie; Ramadani, Arba P; Mercereau-Puijalon, Odile; Augereau, Jean-Michel; Benoit-Vical, Françoise

    2016-03-09

    Plasmodium falciparum resistance to artemisinins, the most potent and fastest acting anti-malarials, threatens malaria elimination strategies. Artemisinin resistance is due to mutation of the PfK13 propeller domain and involves an unconventional mechanism based on a quiescence state leading to parasite recrudescence as soon as drug pressure is removed. The enhanced P. falciparum quiescence capacity of artemisinin-resistant parasites results from an increased ability to manage oxidative damage and an altered cell cycle gene regulation within a complex network involving the unfolded protein response, the PI3K/PI3P/AKT pathway, the PfPK4/eIF2α cascade and yet unidentified transcription factor(s), with minimal energetic requirements and fatty acid metabolism maintained in the mitochondrion and apicoplast. The detailed study of these mechanisms offers a way forward for identifying future intervention targets to fend off established artemisinin resistance.

  5. Facial Diplegia in Plasmodium vivax Malaria.

    Science.gov (United States)

    Sim, Jae Eun; Choi, Young-Chul; Kim, Won-Joo

    2010-06-01

    Facial diplegia has diverse etiologies, including viral and bacterial infections such as diphtheria, syphilis and Lyme disease, and also protozoal infection in very rarely cases. A 20-year-old male patient was admitted to our hospital due to bilateral weakness of the upper and lower facial muscles. Examination revealed that the patient had a facial diplegia of the peripheral type. A peripheral blood smear demonstrated the presence of the asexual trophozoite stage of Plasmodium vivax with ring-form trophozoites, which led to a diagnosis of malaria. A serum work-up revealed increased IgG titers of antibodies to myelin-associated glycoprotein and ganglioside GD1b. The patient was administered antimalarial treatment, 1 week after which he showed signs of recovery. To our knowledge, this is the first case of facial diplegia after malaria infection, providing evidence that the mechanism underlying the condition is related to immune-mediated disease. Facial diplegia can manifest after P. vivax infection.

  6. Wanted Plasmodium falciparum, dead or alive

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    Fatimata Sow

    2015-07-01

    Full Text Available Mechanisms of cell death in unicellular parasites have been subjects of debate for the last decade, with studies demonstrating evidence of apoptosis or non-apoptosis like mechanisms, including necrosis, and autophagy. Recent clarifications on the definition of regulated or accidental cell death by The Nomenclature Committee on Cell Death provides an opportunity to reanalyze some data, re-evaluate conclusions in the light of parasite diversity, and to propose alternative arguments in the context of malaria drug resistance, considering lack of really new drugs in the pipeline. Deciphering the mechanisms of death may help in detection of new drug targets and the design of innovative drugs. However, classifications have been evolving rapidly since initial description of “programmed cell death”, leading to some uncertainty as to whether Plasmodium cell death is accidental or regulated.

  7. Gametocytogenesis : the puberty of Plasmodium falciparum

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    Ariey Frédéric

    2004-07-01

    Full Text Available Abstract The protozoan Plasmodium falciparum has a complex life cycle in which asexual multiplication in the vertebrate host alternates with an obligate sexual reproduction in the anopheline mosquito. Apart from the apparent recombination advantages conferred by sex, P. falciparum has evolved a remarkable biology and adaptive phenotypes to insure its transmission despite the dangers of sex. This review mainly focuses on the current knowledge on commitment to sexual development, gametocytogenesis and the evolutionary significance of various aspects of gametocyte biology. It goes further than pure biology to look at the strategies used to improve successful transmission. Although gametocytes are inevitable stages for transmission and provide a potential target to fight malaria, they have received less attention than the pathogenic asexual stages. There is a need for research on gametocytes, which are a fascinating stage, responsible to a large extent for the success of P. falciparum.

  8. The paroxysm of Plasmodium vivax malaria.

    Science.gov (United States)

    Karunaweera, Nadira D; Wijesekera, Subadra K; Wanasekera, Deepani; Mendis, Kamini N; Carter, Richard

    2003-04-01

    The paroxysms of Plasmodium vivax malaria are antiparasite responses that, although distressing to the human host, almost never impart serious acute pathology. Using plasma and blood cells from P. vivax patients, the cellular and noncellular mediators of these events have been studied ex vivo. The host response during a P. vivax paroxysm was found to involve T cells, monocytes and neutrophils, and the activity, among others, of the pyrogenic cytokines tumor necrosis factor alpha and interleukin 2 in addition to granulocyte macrophage-colony stimulating factor. However, interferon gamma activity, associated with serious acute pathogenesis in other studies on malaria, was absent. Induction of the cytokines active during a P. vivax paroxysm depends upon the presence of parasite products, which are released into the plasma before the paroxysm. Chemical identification of these natural parasite products will be important for our understanding of pathogenesis and protection in malaria.

  9. Plasmodium falciparum drug resistance in Angola.

    Science.gov (United States)

    Fançony, Cláudia; Brito, Miguel; Gil, Jose Pedro

    2016-02-09

    Facing chloroquine drug resistance, Angola promptly adopted artemisinin-based combination therapy as the first-line to treat malaria. Currently, the country aims to consolidate malaria control, while preparing for the elimination of the disease, along with others African countries in the region. However, the remarkable capacity of Plasmodium to develop drug resistance represents an alarming threat for those achievements. Herein, the available, but relatively scarce and dispersed, information on malaria drug resistance in Angola, is reviewed and discussed. The review aims to inform but also to encourage future research studies that monitor and update the information on anti-malarial drug efficacy and prevalence of molecular markers of drug resistance, key fields in the context and objectives of elimination.

  10. Towards an unbiased metabolic profiling of protozoan parasites : optimisation of a Leishmania sampling protocol for HILIC-orbitrap analysis

    NARCIS (Netherlands)

    t'Kindt, Ruben; Jankevics, Andris; Scheltema, Richard A.; Zheng, Liang; Watson, David G.; Dujardin, Jean-Claude; Breitling, Rainer; Coombs, Graham H.; Decuypere, Saskia; Kindt, Ruben t’

    2010-01-01

    Comparative metabolomics of Leishmania species requires the simultaneous identification and quantification of a large number of intracellular metabolites. Here, we describe the optimisation of a comprehensive metabolite extraction protocol for Leishmania parasites and the subsequent optimisation of

  11. Safety and efficacy of the bumped kinase inhibitor BKI-1553 in pregnant sheep experimentally infected with Neospora caninum tachyzoites

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    Roberto Sánchez-Sánchez

    2018-04-01

    Full Text Available Neospora caninum is one of the main causes of abortion in cattle, and recent studies have highlighted its relevance as an abortifacient in small ruminants. Vaccines or drugs for the control of neosporosis are lacking. Bumped kinase inhibitors (BKIs, which are ATP-competitive inhibitors of calcium dependent protein kinase 1 (CDPK1, were shown to be highly efficacious against several apicomplexan parasites in vitro and in laboratory animal models. We here present the pharmacokinetics, safety and efficacy of BKI-1553 in pregnant ewes and foetuses using a pregnant sheep model of N. caninum infection. BKI-1553 showed exposure in pregnant ewes with trough concentrations of approximately 4 μM, and of 1  μM in foetuses. Subcutaneous BKI-1553 administration increased rectal temperatures shortly after treatment, and resulted in dermal nodules triggering a slight monocytosis after repeated doses at short intervals. BKI-1553 treatment decreased fever in infected pregnant ewes already after two applications, resulted in a 37–50% reduction in foetal mortality, and modulated immune responses; IFNγ levels were increased early after infection and IgG levels were reduced subsequently. N. caninum was abundantly found in placental tissues; however, parasite detection in foetal brain tissue decreased from 94% in the infected/untreated group to 69–71% in the treated groups. In summary, BKI-1553 confers partial protection against abortion in a ruminant experimental model of N. caninum infection during pregnancy. In addition, reduced parasite detection, parasite load and lesions in foetal brains were observed. Keywords: Neospora caninum, Sheep, Pregnancy, Treatment, Protein kinase inhibitor, BKI-1553

  12. An explorative study to assess the efficacy of toltrazuril-sulfone (ponazuril) in calves experimentally infected with Neospora caninum.

    Science.gov (United States)

    Kritzner, Sandra; Sager, Heinz; Blum, Jürg; Krebber, Ralph; Greif, Gisela; Gottstein, Bruno

    2002-10-18

    Neospora caninum is an important cause of infectious abortion and stillbirth in cattle world-wide. Infection is common and may frequently be passed from mother to calf (vertical transmission) with no signs of disease. Based on our previous observation that N. caninum-infection can be efficiently controlled with toltrazuril-sulfone (ponazuril) in experimentally infected mice, we addressed the question if efficacy could also be obtained in experimentally infected calves. The study included 19 calves and represents an initial explorative approach to document a basic effectiveness at first. Fifteen animals received each 2 x 10(8) N. caninum trophozoites, half of the dose being injected intravenously and the other half subcutaneously. Efficacy of treatment was assessed using molecular detection of parasite DNA with PCR and pathological alterations by immunohistochemistry in different organs of the animals. Assessment included also clinical, serological and pathophysiological parameters. In those calves medicated with ponazuril (one, or six consecutive days, respectively, starting one day after infection), a complete abrogation of the parasite detectability was obtained in the brain and other organs, while 50% of non-treated calves became PCR-positive in brain and muscles. Clinically, ponazuril chemotherapy of infected calves--in comparison to non-treated infected animals--reduced symptoms (fever), but no differences were observed between treated and non-treated animals with regard to serum enzymes and metabolites. Efficacy of a six-day treatment was also reflected by significantly lower anti-Neospora antibody concentrations developed after infection, when compared to non-treated animals. Based on our findings in this initially explorative approach that indicate a basic effectiveness of ponazuril against experimental N. caninum infection in calves, we plan to follow our chemotherapeutical intervention strategy to control bovine neosporosis with a subsequent more

  13. An explorative study to assess the efficacy of Toltrazuril-sulfone (Ponazuril in calves experimentally infected with Neospora caninum

    Directory of Open Access Journals (Sweden)

    Greif Gisela

    2002-10-01

    Full Text Available Abstract Background Neospora caninum is an important cause of infectious abortion and stillbirth in cattle world-wide. Infection is common and may frequently be passed from mother to calf (vertical transmission with no signs of disease. Based on our previous observation that N. caninum-infection can be efficiently controlled with Toltrazuril-sulfone (Ponazuril in experimentally infected mice, we addressed the question if efficacy could also be obtained in experimentally infected calves. Material and Methods The study included 19 calves and represents an initial explorative approach to document a basic effectiveness at first. Fifteen animals received each 2 x 108N. caninum trophozoites, half of the dose being injected intravenously and the other half subcutaneously. Efficacy of treatment was assessed using molecular detection of parasite DNA with PCR and pathological alterations by immunohistochemistry in different organs of the animals. Assessment included also clinical, serological and pathophysiological parameters. Results In those calves medicated with ponazuril (one, or six consecutive days, respectively, starting one day after infection, a complete abrogation of the parasite detectability was obtained in the brain and other organs, while 50% of non-treated calves became PCR-positive in brain and muscles. Clinically, ponazuril chemotherapy of infected calves – in comparison to non-treated infected animals – reduced symptoms (fever, but no differences were observed between treated and non-treated animals with regard to serum enzymes and metabolites. Efficacy of a six-day treament was also reflected by significantly lower anti-Neospora antibody concentrations developed after infection, when compared to non-treated animals. Conclusion Based on our findings in this initially explorative approach that indicate a basic effectiveness of ponazuril against experimental N. caninum infection in calves, we plan to follow our chemotherapeutical

  14. NcGRA2 as a molecular target to assess the parasiticidal activity of toltrazuril against Neospora caninum.

    Science.gov (United States)

    Strohbusch, M; Müller, N; Hemphill, A; Greif, G; Gottstein, B

    2008-08-01

    The treatment of Neospora caninum infection in the bovine host is still at an experimental stage. In contrast to the in vivo situation, a wide range of compounds have been intensively investigated in cell-culture-based assays. Tools to demonstrate efficacy of treatment have remained conventional including morphological and cell biological criteria. In this work, we present a molecular assay that allows the distinction between live and dead parasites. Live parasites can be detected by measuring the mRNA level of specific genes, making use of the specific mRNA available in live cells. The NcGra2 gene of N. caninum, which is known to be expressed in both tachyzoites and bradyzoites, was used to establish a quantitative real-time RT-PCR, for monitoring parasite viability. Validation of the system in vitro was achieved using Neospora-infected cells that had been treated for 2-20 days with 30 microg/ml toltrazuril. NcGRA2-RT-real time PCR demonstrated that a 10-day toltrazuril-treatment exerted parasitostatic activity, as assessed by the presence of NcGRA2-transcripts, whereas after a 14-day treatment period no NcGRA2-transcripts were detected, showing that the parasites were no longer viable. Concurrently, extended culture for a period of 4 weeks in the absence of the drug following the 14-day toltrazuril treatment did not lead to further parasite proliferation, confirming the parasiticidal effect of the treatment. This assay has the potential to be widely used in the development of novel drugs against N. caninum, with a view to distinguishing between parasiticidal and parasitostatic efficacy of given compounds.

  15. Occurrence of anti-Neospora caninum antibodies in dairy cattle in the western of Santa Catarina, Brazil

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    Marina Paula Lorenzett

    2016-09-01

    Full Text Available ABSTRACT.Lorenzett M.P., Lucca N.J., Henker L.C., Machado G., Gomes D.C., Mendes R.E., Driemeier D. & Casagrande R.A. [Occurrence of anti-Neospora caninum antibodies in dairy cattle in the western of Santa Catarina, Brazil.] Ocorrência de anticorpos anti-Neospora caninum em bovinos leiteiros no oeste do estado de Santa Catarina, Brasil. Revista Brasileira de Medicina Veteriná- ria, 38(3:243-249, 2016. Laboratório de Patologia Animal, Centro de Ciências Agroveterinárias, Universidade do Estado de Santa Catarina, Av. Luiz de Camões, 2090, Lages, SC 88520-000, Brasil. E-mail: renata.casagrande@udesc.br The neosporosis is considered a major cause of neonatal mortality and abortion in cattle, causing great economic and reproductive losses. The aim of this study was to investigate the occurrence of antibodies against N. caninum in dairy cattle in Concordia, which is considered one of the biggest milk producers in the Santa Catarina state. Antibody was detect by indirect immunofluorescence (IFI, with the cut-off of 1:200. Data were analyzed using descriptive and inferential statistics and frequency distribution. The variables questioned was analyzed first by a univariate logistic regression to evaluate the association between abortion history and general management practices used in the farm with seropositive animals were selected for multivariate analysis if P 0.05 for all other variables questioned and its association with seropositive animals. Therefore, in this study it can be concluded that the dairy cattle from this region in study are potentially exposed to infection by N. caninum.

  16. Foetal death in naive heifers inoculated with Neospora caninum isolate Nc-Spain7 at 110 days of pregnancy.

    Science.gov (United States)

    Almería, Sonia; Serrano-Perez, Beatriz; Darwich, Laila; Domingo, Mariano; Mur-Novales, Ramon; Regidor-Cerrillo, Javier; Cabezón, Oscar; Pérez-Maillo, Mónica; Lopez-Helguera, Irene; Fernández-Aguilar, Xavier; Puig-Ribas, Maria; Ortega-Mora, Luis Miguel; García-Ispierto, Irina; Dubey, Jitender P; López-Gatius, Fernando

    2016-09-01

    Neospora caninum infection is a leading cause of abortion in cattle worldwide. The pathogenesis of bovine neosporosis, particularly during the second term of gestation when most abortions occur in naturally infected dams, is poorly understood. In the present study foetal death was observed in 3 of 6 experimentally infected dams at 110 days of gestation after 6 weeks of experimental period. All experimental heifers were febrile between 3 and 5 days post infection (dpi). Inoculated dams seroconverted by 3-4 weeks post-infection with higher mean antibody titres in aborting dams compared to non-aborting heifers, although not significantly (p > 0.05). Neospora caninum DNA was detected in all infected foetuses and placentas, and three infected foetuses also had N. caninum antibodies. The parasite burden was higher in the brain of dead/aborted foetuses than in live foetuses. Interestingly, high IFN-γ production was detected in foetal fluids of a dead foetus found upon euthanasia of its dam, while no IFN-γ was observed in amniotic, allantoic and/or foetal fluids in the three infected foetuses that were alive upon maternal euthanasia. The present study confirms that the infection of dams on gestation day 110 with 10(7) tachyzoites of the Nc-Spain7 isolate causes abortion. The fact that some infected dams aborted and some did not is relevant to the understanding of N. caninum pathogenesis of abortion in naturally infected cows. Copyright © 2016 Elsevier Inc. All rights reserved.

  17. Epidemiology of Plasmodium vivax Malaria in Peru

    Science.gov (United States)

    Rosas-Aguirre, Angel; Gamboa, Dionicia; Manrique, Paulo; Conn, Jan E.; Moreno, Marta; Lescano, Andres G.; Sanchez, Juan F.; Rodriguez, Hugo; Silva, Hermann; Llanos-Cuentas, Alejandro; Vinetz, Joseph M.

    2016-01-01

    Malaria in Peru, dominated by Plasmodium vivax, remains a public health problem. The 1990s saw newly epidemic malaria emerge, primarily in the Loreto Department in the Amazon region, including areas near to Iquitos, the capital city, but sporadic malaria transmission also occurred in the 1990s–2000s in both north-coastal Peru and the gold mining regions of southeastern Peru. Although a Global Fund-supported intervention (PAMAFRO, 2005–2010) was temporally associated with a decrease of malaria transmission, from 2012 to the present, both P. vivax and Plasmodium falciparum malaria cases have rapidly increased. The Peruvian Ministry of Health continues to provide artemesinin-based combination therapy for microscopy-confirmed cases of P. falciparum and chloroquine–primaquine for P. vivax. Malaria transmission continues in remote areas nonetheless, where the mobility of humans and parasites facilitates continued reintroduction outside of ongoing surveillance activities, which is critical to address for future malaria control and elimination efforts. Ongoing P. vivax research gaps in Peru include the following: identification of asymptomatic parasitemics, quantification of the contribution of patent and subpatent parasitemics to mosquito transmission, diagnosis of nonparasitemic hypnozoite carriers, and implementation of surveillance for potential emergence of chloroquine- and 8-aminoquinoline-resistant P. vivax. Clinical trials of tafenoquine in Peru have been promising, and glucose-6-phosphate dehydrogenase deficiency in the region has not been observed to be a limitation to its use. Larger-scale challenges for P. vivax (and malaria in general) in Peru include logistical difficulties in accessing remote riverine populations, consequences of government policy and poverty trends, and obtaining international funding for malaria control and elimination. PMID:27799639

  18. Management practices as risk factors for the presence of bulk milk antibodies to Salmonella, Neospora caninum and Leptospira interrogans serovar hardjo in Irish dairy herds.

    Science.gov (United States)

    O' Doherty, E; Berry, D P; O' Grady, L; Sayers, R

    2014-06-01

    A survey of management practices in 309 Irish dairy herds was used to identify risk factors for the presence of antibodies to Salmonella, Neospora caninum and Leptospira interrogans serovar hardjo in extensively managed unvaccinated dairy herds. A previous study documented a herd-level seroprevalence in bulk milk of 49%, 19% and 86% for Salmonella, Neospora caninum and leptospira interrogans serovar hardjo, respectively in the unvaccinated proportion of these 309 herds in 2009. Association analyses in the present study were carried out using multiple logistic regression models. Herds where cattle were purchased or introduced had a greater likelihood of being positive to leptospira interrogans serovar hardjo (PNeospora caninum (PNeospora caninum possibly due to limited access of dogs to infected materials including afterbirths. The information from this study will assist in the design of suitable control programmes for the diseases under investigation in pasture-based livestock systems.

  19. An agent-based model for Leishmania major infection

    Science.gov (United States)

    Dancik, Garrett M.; Jones, Douglas E.; Dorman, Karin S.

    Leishmania are protozoan parasites transmitted by bites of infected sandflies. Over 20 species of Leishmania, endemic in 88 countries, are capable of causing human disease. Disease is either cutaneous, where skin ulcers occur on exposed surfaces of the body, or visceral, with near certain mortality if untreated. C3HeB/FeJ mice are resistant to L. major, but develop chronic cutaneous lesions when infected with another species L. amazonensis. The well-characterized mechanism of resistance to L. major depends on a CD4+ Thl immune response, macrophage activation, and elimination of the parasite [Sacks 2002]. The factors that account for host susceptibility to L. Amazonensis, however, are not completely understood, despite being generally attributed to a weakened Th1 response [Vanloubbeck 2004].

  20. Leishmania promastigotes: building a safe niche within macrophages

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    Neda eMoradin

    2012-09-01

    Full Text Available Upon their internalization by macrophages, Leishmania promastigotes inhibit phagolysosome biogenesis. The main factor responsible for this inhibition is the promastigote surface glycolipid lipophosphoglycan (LPG. This glycolipid has a profound impact on the phagosome, causing periphagosomal accumulation of F-actin and disruption of phagosomal lipid microdomains. Functionally, this LPG-mediated inhibition of phagosome maturation is characterized by an impaired assembly of the NADPH oxidase and the exclusion of the vesicular proton-ATPase from phagosomes. In this chapter, we review the current knowledge concerning the nature of the intra-macrophage compartment in which Leishmania donovani promastigotes establish infection. We also describe how LPG enables this parasite to remodel the parasitophorous vacuole.

  1. The current status of phlebotomine sandflies (Diptera: Psychodidae) in Tunisia and their role on Leishmania transmission: A review

    OpenAIRE

    Ahmed Tabbabi; Sajida Sboui; Jabeur Daaboub

    2017-01-01

    In Tunisia, the epidemiological situation of leishmaniasis is characterized by the coexistence in a rather circumscribed territory (165000 km2, including the Sahara) of 4 forms of leishmaniasis caused by 3 species: Leishmania infantum, Leishmania major and Leishmania tropica (L. tropica) (synonymous Leishmania killicki). One of the factors determining the clinical, epidemiological and immunological diversity of leishmanioses is certainly the existence of a vector-parasite specificity of of...

  2. Prevention of vertical transmission of Neospora caninum in C57BL/6 mice vaccinated with Brucella abortus strain RB51 expressing N. caninum protective antigens.

    Science.gov (United States)

    Ramamoorthy, Sheela; Sanakkayala, Neelima; Vemulapalli, Ramesh; Jain, Neeta; Lindsay, David S; Schurig, Gerhardt S; Boyle, Stephen M; Sriranganathan, Nammalwar

    2007-11-01

    Bovine abortions caused by the apicomplexan parasite Neospora caninum have been responsible for severe economic losses to the cattle industry. Infected cows either experience abortion or transmit the parasite transplacentally at a rate of up to 95%. Neospora caninum vaccines that can prevent vertical transmission and ensure disruption in the life cycle of the parasite greatly aid in the management of neosporosis in the cattle industry. Brucella abortus strain RB51, a commercially available vaccine for bovine brucellosis, can also be used as a vector to express plasmid-encoded proteins from other pathogens. Neospora caninum protective antigens MIC1, MIC3, GRA2, GRA6 and SRS2 were expressed in strain RB51. Female C57BL/6 mice were vaccinated with a recombinant strain RB51 expressing N. caninum antigen or irradiated tachyzoites, boosted 4 weeks later and then bred. Antigen-specific IgG, IFN-gamma and IL-10 were detected in vaccinated pregnant mice. Vaccinated mice were challenged with 5 x 10(6)N. caninum tachyzoites between days 11-13 of pregnancy. Brain tissue was collected from pups 3 weeks after birth and examined for the presence of N. caninum by real-time PCR. The RB51-MIC3, RB51-GRA6, irradiated tachyzoite vaccine, pooled strain RB51-Neospora vaccine, RB51-MIC1 and RB51-SRS2 vaccines elicited approximately 6-38% protection against vertical transmission. However, the differences in parasite burden in brain tissue of pups from the control and vaccinated groups were highly significant for all groups. Thus, B. abortus strain RB51 expressing the specific N. caninum antigens induced substantial protection against vertical transmission of N. caninum in mice.

  3. Molecular identification of Neospora caninum from calf/foetal brain tissue and among oocysts recovered from faeces of naturally infected dogs in southern Ethiopia.

    Science.gov (United States)

    Asmare, K; Skjerve, E; Bekele, J; Sheferaw, D; Stachurska-Hagen, T; Robertson, L J

    2014-02-01

    This study sought to confirm and investigate further recently published information regarding the occurrence of Neospora caninum in cattle in Ethiopia and investigate infection in dogs, the canine definitive host, in this region. Faecal samples from 383 dogs in Hawassa, Ethiopia were examined by microscopy for Neospora-like oocysts, and positive samples then analysed by a molecular approach (DNA isolation, PCR and sequencing at the ITS1 gene). Brain tissue samples from four late term aborted foetuses, one congenitally defective calf (hind leg arthrogryposis) and placental tissue from cattle in the same area were also examined by the same molecular approach. All foetal, calf and placental tissue were associated with Neospora seropositive dams. A high prevalence of Neospora-like oocysts (11.5 μm±1.5 μm diameter) was observed in faecal samples from dogs (37 positive samples; 9.7% prevalence), and in 17 of these the identification was confirmed by PCR, giving a prevalence of confirmed infection of 4.4%. N. caninum DNA was also detected in all foetal and calf brain tissue samples. Sequencing revealed only minor differences among all PCR products, whether from oocysts or from brain tissue samples. These data provide molecular evidence of the presence of N. caninum infection in both dog and cattle in this region of Ethiopia. Moreover these findings highlight the role of dogs in maintaining and spreading the infection horizontally in the study area. The high frequency of N. caninum infection in household dogs as well as farm dogs is worthy of further investigation. Copyright © 2013 Elsevier B.V. All rights reserved.

  4. FRECUENCIA DE ANTICUERPOS CONTRA Neospora caninum Y Toxoplasma gondii EN CANES CON SIGNOS CLÍNICOS DE AFECCIÓN NEUROMUSCULAR.

    OpenAIRE

    Ruíz R., Nelson; Laboratorio de Microbiología y Parasitología Veterinaria, Facultad de Medicina Veterinaria, Universidad Nacional Mayor de San Marcos, Lima-Perú.; Casas A., Eva; Laboratorio de Microbiología y Parasitología Veterinaria; Suárez A., Francisco; Laboratorio de Medicina Veterinaria Preventiva, Facultad de Medicina Veterinaria, Universidad Nacional Mayor de San Marcos, Lima-Perú.; Díaz C., Diego; Clínica de Animales Menores, Facultad de Medicina Veterinaria, Universidad Nacional Mayor de San Marcos, Lima; Fernández P., Viviana; Clínica de Animales Menores, Facultad de Medicina Veterinaria, Universidad Nacional Mayor de San Marcos, Lima

    2012-01-01

    Toxoplasma gondii and Neospora caninum can cause neuromuscular disorders in dogs. The aim of the Case-Control study was to determine the association between antibodies anti N. caninum and anti-T. gondii in dogs with neuromuscular disorders. Blood samples were collected in 96 and 120 dogs with and without clinical signs of neuromuscular disorders respectively. Serum samples were analyzed by the indirect immunofluorescence test (IFI) for the detection of IgG antibodies, considering positive the...

  5. Changes to cholesterol trafficking in macrophages by Leishmania parasites infection.

    Science.gov (United States)

    Semini, Geo; Paape, Daniel; Paterou, Athina; Schroeder, Juliane; Barrios-Llerena, Martin; Aebischer, Toni

    2017-08-01

    Leishmania spp. are protozoan parasites that are transmitted by sandfly vectors during blood sucking to vertebrate hosts and cause a spectrum of diseases called leishmaniases. It has been demonstrated that host cholesterol plays an important role during Leishmania infection. Nevertheless, little is known about the intracellular distribution of this lipid early after internalization of the parasite. Here, pulse-chase experiments with radiolabeled cholesteryl esterified to fatty acids bound to low-density lipoproteins indicated that retention of this source of cholesterol is increased in parasite-containing subcellular fractions, while uptake is unaffected. This is correlated with a reduction or absence of detectable NPC1 (Niemann-Pick disease, type C1), a protein responsible for cholesterol efflux from endocytic compartments, in the Leishmania mexicana habitat and infected cells. Filipin staining revealed a halo around parasites within parasitophorous vacuoles (PV) likely representing free cholesterol accumulation. Labeling of host cell membranous cholesterol by fluorescent cholesterol species before infection revealed that this pool is also trafficked to the PV but becomes incorporated into the parasites' membranes and seems not to contribute to the halo detected by filipin. This cholesterol sequestration happened early after infection and was functionally significant as it correlated with the upregulation of mRNA-encoding proteins required for cholesterol biosynthesis. Thus, sequestration of cholesterol by Leishmania amastigotes early after infection provides a basis to understand perturbation of cholesterol-dependent processes in macrophages that were shown previously by others to be necessary for their proper function in innate and adaptive immune responses. © 2017 The Authors. MicrobiologyOpen published by John Wiley & Sons Ltd.

  6. Impact of Leishmania Metalloprotease GP63 on Macrophage Signalling

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    Amandine eIsnard

    2012-05-01

    Full Text Available Several Leishmania surface molecules are known to be important virulence factors. For instance, LPG is recognized as one of the key virulence factor for Leishmania. Interestingly, recent findings permit to believe that the Leishmania GP63 could be also a critical one. GP63 is a metalloprotease found in all Leishmania species under different forms going from membrane-bound to extracellularly secreted ones. Even before parasite entries into the host macrophage, GP63 provides parasite resistance to the complement-mediated lysis and facilitate promastigote engulfment by macrophages. Additionally, it has been found that the degradation of proteins from the macrophage extracellular matrix by GP63 could confer protection to promastigotes, as well as amastigotes, during their initial interaction with the host cell. More recently, GP63 has been observed to rapidly enter within the host macrophage -in part via lipid raft microdomains- and to be pivotal for the subversion of host innate immune response. For instance, it has been found to be responsible for the activation of negative regulatory mechanisms involving activation of protein tyrosine phosphatases (PTPs; SHP-1, PTP1B and TCPTP that lead to the alteration of several key signalling pathways utilizing JAK and MAP kinases family members, as well as the pivotal IRAK-1 kinase for toll like-dependent signalling. In addition, it has been recently reported that inactivation of some transcription factors such as AP-1 occurs directly in the nuclear environment of the infected cells, and to involve the cleavage and degradation of c-jun and c-fos family members by GP63. Altogether, this signalling inactivation under the mediation of GP63 concurs to inhibit important antimicrobial actions usually under the regulation of the innate immune response, and therefore favouring the survival and propagation of the parasite once into its host intracellular environment.

  7. Leishmania parasite detection and quantification using PCR-ELISA

    Czech Academy of Sciences Publication Activity Database

    Kobets, Tetyana; Badalová, Jana; Grekov, Igor; Havelková, Helena; Lipoldová, Marie

    2010-01-01

    Roč. 5, č. 6 (2010), s. 1074-1080 ISSN 1754-2189 R&D Projects: GA ČR GA310/08/1697; GA MŠk(CZ) LC06009 Institutional research plan: CEZ:AV0Z50520514 Keywords : polymerase chain reaction * Leishmania major infection * parasite quantification Subject RIV: EB - Genetics ; Molecular Biology Impact factor: 8.362, year: 2010

  8. Microbial stasis of Leishmania enriettii in activated guinea pig macrophages

    International Nuclear Information System (INIS)

    Groocock, C.M.; Soulsby, E.J.L.

    1980-01-01

    Peritoneal exudate cells (PEC) from Leishmania-sensitized guinea pigs were cultured in vitro in the presence (activated) or absence (non-activated) of leishmanial antigen for 24 or 48 hours. These were then labelled with 51 Cr and challenged with 125 I-labelled promastigotes. The changing relationship between the macrophage and the parasite was monitored by observing changes in the ratio of the cell-associated isotopes. Highly significant differences in the ratio change developed during culture. These differences were a result of the activated cultures showing a higher release of 51 Cr and a lower release of 125 I when compared with the non-activated cells, at 12 hours the percentage release of 125 I from the parasite within the activated macrophage was fourfold less than that released by parasites within non-activated cells (9.2% versus 38.3%) and tenfold less than that released from glutaraldehyde-killed organisms phagocytosed by activated macrophages (91.6%). These studies indicate that stasis rather than killing of leishmaniae occurs in the activated macrophage in vitro. Parallel experiments evaluated by the visual counting of leishmaniae within the macrophages support these data. PEC from tuberculin-sensitized guinea pigs activated in vitro by purified protein derivative showed little or no activity against leishmaniae, indicating a specific requirement for this microbial stasis by activated macrophages. As a corollary of this, peritoneal exudate lymphocytes separated from the same preparations of PEC were shown to be specifically reactive to leishmanial antigen by transformation and incorporation of 3 H-thymidine. (author)

  9. Human mixed infections of Leishmania spp. and Leishmania-Trypanosoma cruzi in a sub Andean Bolivian area: identification by polymerase chain reaction/hybridization and isoenzyme

    Directory of Open Access Journals (Sweden)

    B Bastrenta

    2003-03-01

    Full Text Available Parasites belonging to Leishmania braziliensis, Leishmania donovani, Leishmania mexicana complexes and Trypanosoma cruzi (clones 20 and 39 were searched in blood, lesions and strains collected from 28 patients with active cutaneous leishmaniasis and one patient with visceral leishmaniasis. PCR-hybridization with specific probes of Leishmania complexes (L. braziliensis, L. donovani and L. mexicana and T. cruzi clones was applied to the different DNA samples. Over 29 patients, 8 (27.6% presented a mixed infection Leishmania complex species, 17 (58.6% a mixed infection Leishmania-T. cruzi, and 4 (13.8% a multi Leishmania-T. cruzi infection. Several patients were infected by the two Bolivian major clones 20 and 39 of T. cruzi (44.8%. The L. braziliensis complex was more frequently detected in lesions than in blood and a reverse result was observed for L. mexicana complex. The polymerase chain reaction-hybridization design offers new arguments supporting the idea of an underestimated rate of visceral leishmanisis in Bolivia. Parasites were isolated by culture from the blood of two patients and lesions of 10 patients. The UPGMA (unweighted pair-group method with arithmetic averages dendrogram computed from Jaccard's distances obtained from 11 isoenzyme loci data confirmed the presence of the three Leishmania complexes and undoubtedly identified human infections by L. (V. braziliensis, L. (L. chagasi and L. (L. mexicana species. Additional evidence of parasite mixtures was visualized through mixed isoenzyme profiles, L. (V. braziliensis-L. (L. mexicana and Leishmania spp.-T. cruzi.The epidemiological profile in the studied area appeared more complex than currently known. This is the first report of parasitological evidence of Bolivian patients with trypanosomatidae multi infections and consequences on the diseases' control and patient treatments are discussed.

  10. Monocyte-Derived Signals Activate Human Natural Killer Cells in Response to Leishmania Parasites

    Directory of Open Access Journals (Sweden)

    Helena Messlinger

    2018-01-01

    Full Text Available Activated natural killer (NK cells release interferon (IFN-γ, which is crucial for the control of intracellular pathogens such as Leishmania. In contrast to experimental murine leishmaniasis, the human NK cell response to Leishmania is still poorly characterized. Here, we investigated the interaction of human blood NK cells with promastigotes of different Leishmania species (Leishmania major, Leishmania mexicana, Leishmania infantum, and Leishmania donovani. When peripheral blood mononuclear cells or purified NK cells and monocytes (all derived from healthy blood donors from Germany without a history of leishmaniasis were exposed to promastigotes, NK cells showed increased surface expression of the activation marker CD69. The extent of this effect varied depending on the Leishmania species; differences between dermotropic and viscerotropic L. infantum strains were not observed. Upregulation of CD69 required direct contact between monocytes and Leishmania and was partly inhibitable by anti-interleukin (IL-18. Unexpectedly, IL-18 was undetectable in most of the supernatants (SNs of monocyte/parasite cocultures. Confocal fluorescence microscopy of non-permeabilized cells revealed that Leishmania-infected monocytes trans-presented IL-18 to NK cells. Native, but not heat-treated SNs of monocyte/Leishmania cocultures also induced CD69 on NK cells, indicating the involvement of a soluble heat-labile factor other than IL-18. A role for the NK cell-activating cytokines IL-1β, IL-2, IL-12, IL-15, IL-21, and IFN-α/β was excluded. The increase of CD69 was not paralleled by NK cell IFN-γ production or enhanced cytotoxicity. However, prior exposure of NK cells to Leishmania parasites synergistically increased their IFN-γ release in response to IL-12, which was dependent on endogenous IL-18. CD1c+ dendritic cells were identified as possible source of Leishmania-induced IL-12. Finally, we observed that direct contact between Leishmania and NK cells

  11. The Dynamics of Lateral Gene Transfer in Genus Leishmania - A Route for Adaptation and Species Diversification.

    Science.gov (United States)

    Vikeved, Elisabet; Backlund, Anders; Alsmark, Cecilia

    2016-01-01

    The genome of Leishmania major harbours a comparably high proportion of genes of prokaryote origin, acquired by lateral gene transfer (LGT). Some of these are present in closely related trypanosomatids, while some are detected in Leishmania only. We have evaluated the impact and destiny of LGT in genus Leishmania. To study the dynamics and fate of LGTs we have performed phylogenetic, as well as nucleotide and amino acid composition analyses within orthologous groups of LGTs detected in Leishmania. A set of universal trypanosomatid LGTs was added as a reference group. Both groups of LGTs have, to some extent, ameliorated to resemble the recipient genomes. However, while virtually all of the universal trypanosomatid LGTs are distributed and conserved in the entire genus Leishmania, the LGTs uniquely present in genus Leishmania are more prone to gene loss and display faster rates of evolution. Furthermore, a PCR based approach has been employed to ascertain the presence of a set of twenty LGTs uniquely present in genus Leishmania, and three universal trypanosomatid LGTs, in ten additional strains of Leishmania. Evolutionary rates and predicted expression levels of these LGTs have also been estimated. Ten of the twenty LGTs are distributed and conserved in all species investigated, while the remainder have been subjected to modifications, or undergone pseudogenization, degradation or loss in one or more species. LGTs unique to the genus Leishmania have been acquired after the divergence of Leishmania from the other trypanosomatids, and are evolving faster than their recipient genomes. This implies that LGT in genus Leishmania is a continuous and dynamic process contributing to species differentiation and speciation. This study also highlights the importance of carefully evaluating these dynamic genes, e.g. as LGTs have been suggested as potential drug targets.

  12. Phylogenetic analysis of lack gene sequences for 22 Chinese Leishmania isolates.

    Science.gov (United States)

    Zhang, Chun-Ying; Zhou, Juan; Ding, Bin; Lu, Xiao-Jun; Xiao, Yu-Ling; Hu, Xiao-Su; Ma, Ying

    2013-07-01

    The phylogenetic relationships between Chinese Leishmania strains were investigated using lack (Leishmania homolog of receptors for activated protein kinase C) gene sequences, and the power of this gene was assessed for understanding the epidemiology and population genetics of Leishmania. The lack gene sequences from Leishmania isolates were sequenced after polymerase chain reaction (PCR) amplification. Sequence alignment was performed and a phylogenetic tree was created using the MEGA 5.0 software program. Sequences of 850 bp were analyzed for each of the Leishmania strains collected from different locations in China, and minor differences in sequences were noted between the strains. Four distinct groups formed according to differences in the sequences of the lack gene. Group I consisted of 12 isolates from Shandong, Xinjiang, Gansu and Sichuan. These strains are part of the Leishmania donovani complex and are pathogenic to humans and canines. Group II included six isolates from Xinjiang and a reference strain, Leishmania turanica. Group III contained two isolates (one from a sand fly in Xinjiang and one from a rodent in Inner Mongolia) and they were identified as Leishmania gerbilli. Finally, group IV contained a strain from a sand fly in Xinjiang and a strain from a lizard in Inner Mongolia, and these strains were found to be Sauroleishmania. The Chinese Leishmania isolates formed four groups based on differences in the sequences of the lack gene, and this result is consistent with previous studies. Phylogenetic analysis suggests that the Leishmania isolates from China are more complicated than previously thought. There is consensus between genetic clustering and identification using classical methods, which means that the lack gene yields polymorphic information that could be used for genotyping Leishmania isolates. Copyright © 2013 Elsevier B.V. All rights reserved.

  13. A Historical Overview of the Classification, Evolution, and Dispersion of Leishmania Parasites and Sandflies

    Science.gov (United States)

    Akhoundi, Mohammad; Kuhls, Katrin; Cannet, Arnaud; Votýpka, Jan; Marty, Pierre; Delaunay, Pascal; Sereno, Denis

    2016-01-01

    Background The aim of this study is to describe the major evolutionary historical events among Leishmania, sandflies, and the associated animal reservoirs in detail, in accordance with the geographical evolution of the Earth, which has not been previously discussed on a large scale. Methodology and Principal Findings Leishmania and sandfly classification has always been a controversial matter, and the increasing number of species currently described further complicates this issue. Despite several hypotheses on the origin, evolution, and distribution of Leishmania and sandflies in the Old and New World, no consistent agreement exists regarding dissemination of the actors that play roles in leishmaniasis. For this purpose, we present here three centuries of research on sandflies and Leishmania descriptions, as well as a complete description of Leishmania and sandfly fossils and the emergence date of each Leishmania and sandfly group during different geographical periods, from 550 million years ago until now. We discuss critically the different approaches that were used for Leishmana and sandfly classification and their synonymies, proposing an updated classification for each species of Leishmania and sandfly. We update information on the current distribution and dispersion of different species of Leishmania (53), sandflies (more than 800 at genus or subgenus level), and animal reservoirs in each of the following geographical ecozones: Palearctic, Nearctic, Neotropic, Afrotropical, Oriental, Malagasy, and Australian. We propose an updated list of the potential and proven sandfly vectors for each Leishmania species in the Old and New World. Finally, we address a classical question about digenetic Leishmania evolution: which was the first host, a vertebrate or an invertebrate? Conclusions and Significance We propose an updated view of events that have played important roles in the geographical dispersion of sandflies, in relation to both the Leishmania species they

  14. A Historical Overview of the Classification, Evolution, and Dispersion of Leishmania Parasites and Sandflies.

    Science.gov (United States)

    Akhoundi, Mohammad; Kuhls, Katrin; Cannet, Arnaud; Votýpka, Jan; Marty, Pierre; Delaunay, Pascal; Sereno, Denis

    2016-03-01

    The aim of this study is to describe the major evolutionary historical events among Leishmania, sandflies, and the associated animal reservoirs in detail, in accordance with the geographical evolution of the Earth, which has not been previously discussed on a large scale. Leishmania and sandfly classification has always been a controversial matter, and the increasing number of species currently described further complicates this issue. Despite several hypotheses on the origin, evolution, and distribution of Leishmania and sandflies in the Old and New World, no consistent agreement exists regarding dissemination of the actors that play roles in leishmaniasis. For this purpose, we present here three centuries of research on sandflies and Leishmania descriptions, as well as a complete description of Leishmania and sandfly fossils and the emergence date of each Leishmania and sandfly group during different geographical periods, from 550 million years ago until now. We discuss critically the different approaches that were used for Leishmana and sandfly classification and their synonymies, proposing an updated classification for each species of Leishmania and sandfly. We update information on the current distribution and dispersion of different species of Leishmania (53), sandflies (more than 800 at genus or subgenus level), and animal reservoirs in each of the following geographical ecozones: Palearctic, Nearctic, Neotropic, Afrotropical, Oriental, Malagasy, and Australian. We propose an updated list of the potential and proven sandfly vectors for each Leishmania species in the Old and New World. Finally, we address a classical question about digenetic Leishmania evolution: which was the first host, a vertebrate or an invertebrate? We propose an updated view of events that have played important roles in the geographical dispersion of sandflies, in relation to both the Leishmania species they transmit and the animal reservoirs of the parasites.

  15. Leishmania (Viannia naiffi: rare enough to be neglected?

    Directory of Open Access Journals (Sweden)

    Giselle Aparecida Fagundes-Silva

    2015-09-01

    Full Text Available In the Brazilian Amazon, American tegumentary leishmaniasis (ATL is endemic and presents a wide spectrum of clinical manifestations due, in part, to the circulation of at least seven Leishmaniaspecies. Few reports of Leishmania (Viannia naiffiinfection suggest that its occurrence is uncommon and the reported cases present a benign clinical course and a good response to treatment. This study aimed to strengthen the clinical and epidemiological importance of L. (V. naiffiin the Amazon Region (Manaus, state of Amazonas and to report therapeutic failure in patients infected with this species. Thirty Leishmania spp samples isolated from cutaneous lesions were characterised by multilocus enzyme electrophoresis. As expected, the most common species was Leishmania (V. guyanensis (20 cases. However, a relevant number ofL. (V. naiffi patients (8 cases was observed, thus demonstrating that this species is not uncommon in the region. No patient infected withL. (V. naiffievolved to spontaneous cure until the start of treatment, which indicated that this species may not have a self-limiting nature. In addition, two of the patients experienced a poor response to antimonial or pentamidine therapy. Thus, either ATL cases due to L. (V. naifficannot be as uncommon as previously thought or this species is currently expanding in this region.

  16. Transmission of Leishmania in coffee plantations of Minas Gerais, Brazil

    Directory of Open Access Journals (Sweden)

    Bruce Alexander

    2002-07-01

    Full Text Available Transmission of Leishmania was studied in 27 coffee plantations in the Brazilian State of Minas Gerais. Eighteen females and six males (11.6% of the people tested, aged between 7-65 gave a positive response to the Montenegro skin test. Awareness of sand flies based on the ability of respondents to identify the insects using up to seven predetermined characteristics was significantly greater among inhabitants of houses occupied by at least one Mn+ve individual. Five species of phlebotomine sand fly, including three suspected Leishmania vectors, were collected within plantations under three different cultivation systems. Four of these species i.e., Lu. fischeri (Pinto 1926, Lu. migonei (França 1920, Lu. misionensis (Castro 1959 and Lutzomyia whitmani (Antunes & Coutinho 1939 were collected in an organic plantation and the last of these was also present in the other two plantation types. The remaining species, Lu. intermedia (Lutz & Neiva 1912, was collected in plantations under both the "adensado" and "convencional" systems. The results of this study indicate that transmission of Leishmania to man in coffee-growing areas of Minas Gerais may involve phlebotomine sand flies that inhabit plantations.

  17. [Cutaneous leishmaniasis due to Leishmania infantum associated with HIV].

    Science.gov (United States)

    Diatta, B-A; Diallo, M; Diadie, S; Faye, B; Ndiaye, M; Hakim, H; Diallo, S; Seck, B; Niang, S-O; Kane, A; Dieng, M-T

    2016-10-01

    In Senegal, reported cases of cutaneous leishmaniasis are often due to Leishmania major. Immunosuppression related to HIV infection contributes to the emergence of leishmaniasis in humans and to cutaneous localization of viscerotropic species. We report the first observed case in Senegal of opportunistic cutaneous leishmaniasis due to Leishmania infantum associated with HIV. A 5-year-old boy presented crusted ulcerative lesions of the scalp and left forearm, together with axillary and cervical lymphadenopathy present for two months. Direct parasitological examination of the scalp and arm lesions, coupled with liquid aspiration of lymph nodes and bone marrow, enabled identification of amastigote forms of Leishmania. Polymerase chain reaction performed on skin, lymph node and bone marrow biopsy samples allowed identification of L. infantum. The child was positive for HIV1. Treatment of HIV infection and leishmaniasis resulted in clinical improvement. Co-infection with cutaneous leishmaniasis due to L. infantum and HIV is a complex combination in terms of the related therapeutic issues. The clinical and laboratory outcomes depend on restoration of immunity and on the efficacy, safety and availability of anti-leishmaniasis drugs. Copyright © 2016 Elsevier Masson SAS. All rights reserved.

  18. Application of the microscopic method in cutaneous leishmania diagnosis

    Directory of Open Access Journals (Sweden)

    Mohammed Wael Daboul

    2011-10-01

    Full Text Available Introduction: Cutaneous leishmania is spreading fast. This study aims at developing the microscopic method to achieve a full detection of all positive cases of leishmania.Methods: 50 human cases have been studied by applying microscopic smears stained with Wright stain. Microscopic photos were taken for the presumed unfamiliar figures.Results: Mononuclear cells with tails are present at a rate of (98%. They are associated with Leishman Donovan (LD bodies in 50% of the cases. The polygonal figures and the spherical forms are present at the same rate (60% and are associated with LD bodies in 24% of the cases. The small promastigote like forms are seen at a rate of (76% and are associated with LD bodies in 26% of the cases. The giant promastigotes like forms are present in (80% of the cases and are associated with LD bodies in 28% of the cases. Candle flame forms are present in (40% of the cases and are associated with the LD bodies in 21% of the cases.Discussion: It is applicable to use those discovered figures in diagnosing cutaneous leishmania.

  19. Ocorrência de anticorpos anti-Neospora spp. em jumentos (Equus asinus no estado de Sucre - Colômbia

    Directory of Open Access Journals (Sweden)

    R.D. Blanco

    2014-04-01

    Full Text Available A neosporose tem grande importância em bovinos, e sua patogênese neste hospedeiro, em termos gerais, está esclarecida, porém, em equídeos é pobremente conhecida. Na Colômbia ainda não foram reportados anticorpos Anti-Neospora spp. em equídeos, sendo assim objetivou-se no presente estudo avaliar a ocorrência do parasito em jumentos (Equus asinus de fazendas que apresentavam risco da doença nestes animais. Foram utilizados 56 animais no estado de Sucre (Colômbia, escolhidos aleatoriamente dentro das fazendas selecionadas. Utilizou-se um peptídeo recombinante originado de Neospora caninum (NcGRA1 para o diagnóstico por Dot-ELISA, e o soro foi diluído em 1:200. Este estudo reporta, pela primeira vez no estado de Sucre e na Colômbia, a presença de anticorpos anti-Neospora spp. na espécie Equus asinus, com uma ocorrência de 19,7% (11/56 dos animais amostrados.

  20. Evaluation of two Neospora caninum recombinant antigens for use in an enzyme-linked immunosorbent assay for the diagnosis of bovine neosporosis.

    Science.gov (United States)

    Lally, N C; Jenkins, M C; Dubey, J P

    1996-01-01

    Neospora caninum is a recently described apicomplexan parasite which causes paralysis and death in dogs. Neospora parasites also cause abortion and neonatal morbidity in cattle, sheep, goats, and horses, and neosporosis is emerging as an important cause of bovine abortion worldwide. The purpose of this study was to identify N. caninum cDNA clones encoding antigens that would be useful for the immunodiagnosis of bovine neosporosis. Two N. caninum tachyzoite cDNA clones expressing antigens that were recognized by serum from naturally and experimentally infected cattle were identified. The DNA sequences of these clones were determined, and the inserts were subcloned into the plasmid expression vector pTrcHisB. Both recombinant antigens, expressed as fusion proteins with a His6 tag, were purified on a nickel-chelating affinity column and evaluated in separate enzyme-linked immunosorbent assays (ELISAs). Both recombinant antigen ELISAs were capable of distinguishing between sera from Neospora-infected cows and sera from uninfected control cows. Furthermore, both assays were able to detect an antibody response in animals that were experimentally inoculated with N. caninum. Neither antigen showed evidence of cross-reactivity with serum from animals inoculated with the closely related parasites Toxoplasma gondii, Sarcocystis cruzi, Sarcocystis hominis, and Sarcocystis hirsuta. PMID:8705668

  1. Th1 Cell Development Induced by Cysteine Proteinases A and B in Localized Cutaneous Leishmaniasis Due to Leishmania guyanensis

    Science.gov (United States)

    Pascalis, Hervé; Lavergne, Anne; Bourreau, Eliane; Prévot-Linguet, Ghislaine; Kariminia, Amina; Pradinaud, Roger; Rafati, Sima; Launois, Pascal

    2003-01-01

    The cysteine proteinases CPA and CPB from Leishmania major induced Th1 responses in patients with leishmaniasis due to Leishmania guyanensis. Furthermore, cysteine proteinases induced neither interleukin 4 (IL-4) nor IL-13 and low levels of IL-10 in controls and patients. The results suggest that CPs would be quite good candidates for a vaccine against different Leishmania species. PMID:12704171

  2. Antileishmanial activity of licochalcone A in mice infected with Leishmania major and in hamsters infected with Leishmania donovani

    DEFF Research Database (Denmark)

    Chen, M; Christensen, S B; Theander, T G

    1994-01-01

    This study was designed to examine the antileishmanial activity of the oxygenated chalcone licochalcone A in mice and hamsters infected with Leishmania parasites. Intraperitoneal administration of licochalcone A at doses of 2.5 and 5 mg/kg of body weight per day completely prevented lesion...... development in BALB/c mice infected with Leishmania major. Treatment of hamsters infected with L. donovani with intraperitoneal administration of licochalcone A at a dose of 20 mg/kg of body weight per day for 6 consecutive days resulted in a > 96% reduction of parasite load in the liver and the spleen...... compared with values for untreated control animals. The [3H]thymidine uptake by the parasites isolated from the treated hamsters was only about 1% of that observed in parasites isolated from the controls. Oral administration of licochalcone A at concentrations of 5 to 150 mg/kg of body weight per day for 6...

  3. Primate malarias: Diversity, distribution and insights for zoonotic Plasmodium

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    Christina Faust

    2015-12-01

    Full Text Available Protozoans within the genus Plasmodium are well-known as the causative agents of malaria in humans. Numerous Plasmodium species parasites also infect a wide range of non-human primate hosts in tropical and sub-tropical regions worldwide. Studying this diversity can provide critical insight into our understanding of human malarias, as several human malaria species are a result of host switches from non-human primates. Current spillover of a monkey malaria, Plasmodium knowlesi, in Southeast Asia highlights the permeability of species barriers in Plasmodium. Also recently, surveys of apes in Africa uncovered a previously undescribed diversity of Plasmodium in chimpanzees and gorillas. Therefore, we carried out a meta-analysis to quantify the global distribution, host range, and diversity of known non-human primate malaria species. We used published records of Plasmodium parasites found in non-human primates to estimate the total diversity of non-human primate malarias globally. We estimate that at least three undescribed primate malaria species exist in sampled primates, and many more likely exist in unstudied species. The diversity of malaria parasites is especially uncertain in regions of low sampling such as Madagascar, and taxonomic groups such as African Old World Monkeys and gibbons. Presence–absence data of malaria across primates enables us to highlight the close association of forested regions and non-human primate malarias. This distribution potentially reflects a long coevolution of primates, forest-adapted mosquitoes, and malaria parasites. The diversity and distribution of primate malaria are an essential prerequisite to understanding the mechanisms and circumstances that allow Plasmodium to jump species barriers, both in the evolution of malaria parasites and current cases of spillover into humans.

  4. Biodistribution of meglumine antimoniate in healthy and Leishmania (Leishmania infantum chagasi-infected BALB/c mice

    Directory of Open Access Journals (Sweden)

    Samanta Etel Treiger Borborema

    2013-08-01

    Full Text Available Pentavalent antimonials such as meglumine antimoniate (MA are the primary treatments for leishmaniasis, a complex disease caused by protozoan parasites of the genus Leishmania . Despite over 70 years of clinical use, their mechanisms of action, toxicity and pharmacokinetics have not been fully elucidated. Radiotracer studies performed on animals have the potential to play a major role in pharmaceutical development. The aims of this study were to prepare an antimony radiotracer by neutron irradiation of MA and to determine the biodistribution of MA in healthy and Leishmania (Leishmania infantum chagasi-infected mice. MA (Glucantime(r was neutron irradiated inside the IEA-R1 nuclear reactor, producing two radioisotopes, 122Sb and 124Sb, with high radionuclidic purity and good specific activity. This irradiated compound presented anti-leishmanial activity similar to that of non-irradiated MA in both in vitro and in vivo evaluations. In the biodistribution studies, healthy mice showed higher uptake of antimony in the liver than infected mice and elimination occurred primarily through biliary excretion, with a small proportion of the drug excreted by the kidneys. The serum kinetic curve was bi-exponential, with two compartments: the central compartment and another compartment associated with drug excretion. Radiotracers, which can be easily produced by neutron irradiation, were demonstrated to be an interesting tool for answering several questions regarding antimonial pharmacokinetics and chemotherapy.

  5. Natural infection of phlebotomines (Diptera: Psychodidae) by Leishmania (Leishmania) amazonensis in an area of ecotourism in Central-Western Brazil.

    Science.gov (United States)

    Brilhante, Andreia Fernandes; Nunes, Vânia Lúcia Brandão; Kohatsu, Kleber Augusto; Galati, Eunice Aparecida Bianchi; Rocca, Maria Elizabeth Ghizzi; Ishikawa, Edna Aoba Yassui

    2015-01-01

    Bonito municipality, known as an area of ecoturism, in Mato Grosso do Sul state, Brazil, is also a focus of visceral and cutaneous leishmaniases, with cases registered in both human and canine populations. This study sought to investigate natural infection by flagellate forms of Leishmania in phlebotomines of the urban area of Bonito. Sand flies were collected fortnightly from October 2005 to July 2006 with modified automatic light traps installed in peridomiciles and animal shelters in the center and on the outskirts of the city. The females were dissected and their guts observed under an optical microscope. A total of 1977 specimens were captured, Lutzomyia longipalpis (88.4 %) and Bichromomyia flaviscutelata (3.0 %) being the most frequent species. Bi. flaviscutellata was found infected by flagellates that were identified as Leishmania (Leishmania) amazonensis by indirect immunofluorescence reaction, employing monoclonal antibodies and the biotin-avidin system. This is the first report of natural infection by L. amazonensis in Bi. flaviscutellata in a Brazilian urban area. As Bi. flaviscutellata is only slightly attracted by humans, the transmission of L. amazonensis in the study area may have a zoonotic character; however, the sympatric occurrence of this parasite and Lu. longipalpis should be taken into consideration by the local health authorities since this sand fly has already been found with L. amazonensis DNA in a focus of canine visceral leishmaniasis in Bonito municipality.

  6. Surveillance for antibodies to Leishmania spp. in dogs from Sri Lanka and India

    Science.gov (United States)

    The global distribution of leishmaniasis is rapidly expanding into new geographic regions. Dogs are the primary reservoir hosts for human visceral leishmaniasis (VL) caused by infection with Leishmania infantum. Natural infections with other Leishmania species can occur in dogs, but their role as re...

  7. Development of a dipstick assay for detection of Leishmania-specific canine antibodies

    NARCIS (Netherlands)

    Schallig, Henk D. F. H.; Cardoso, Luís; Hommers, Marieke; Kroon, Nel; Belling, Guus; Rodrigues, Manuela; Semião-Santos, Saul J.; Vetter, Hans

    2004-01-01

    A dipstick assay, based on Leishmania infantum antigen, for the rapid detection of Leishmania-specific antibodies in canine serum samples was developed and evaluated. After determination of optimal dipstick test conditions, test performance was compared with two existing serological tests, i.e., the

  8. Licochalcone A, a novel antiparasitic agent with potent activity against human pathogenic protozoan species of Leishmania

    DEFF Research Database (Denmark)

    Chen, M; Christensen, S B; Blom, J

    1993-01-01

    Licochalcone A, an oxygenated chalcone isolated from the roots of Chinese licorice plant, inhibited the growth of both Leishmania major and Leishmania donovani promastigotes and amastigotes. The structure of the licochalcone A was established by mass and nuclear magnetic resonance spectroscopies ...

  9. Leukodepletion filters reduce Leishmania in blood products when used at collection or at the bedside.

    Science.gov (United States)

    Cardo, Lisa J; Salata, Jeanne; Harman, Ronald; Mendez, Juan; Weina, Peter J

    2006-06-01

    Leishmania is an intracellular parasite of monocytes transmissible by transfusion. The feasibility of reducing Leishmania with leukodepletion filters was studied. At collection, infected blood contains the amastigote form of Leishmania within monocytes. Amastigotes cause the rupture of monocytes releasing free amastigotes that convert to promastigotes, which exist extracellularly at blood storage temperatures. Leukodepletion filters were tested at various time points in this process. Blood products were infected with Leishmania organisms and then filtered with whole-blood filters at collection, with bedside filters after storage, and to determine whether free promastigotes could be eliminated. Filtration at collection reduced Leishmania by 3 to 4 log or to the level of detection. Filtration of infected red cells after 2 weeks of storage showed a reduction of Leishmania by 4 log. Filtration resulted in a 6- to 8-log reduction in promastigotes either in the presence or in the absence of white cells within the filter. Filtration at the time of collection and after storage of Leishmania-infected blood resulted in a substantial reduction of free and intracellular organisms. There is currently no donor screen for Leishmania. Until adequate testing is developed, the use of leukodepletion filters could add to the safety of the blood supply.

  10. Molecular Identification of Leishmania spp. in Sand Flies (Diptera: Psychodidae, Phlebotominae) From Ecuador.

    Science.gov (United States)

    Quiroga, Cristina; Cevallos, Varsovia; Morales, Diego; Baldeón, Manuel E; Cárdenas, Paúl; Rojas-Silva, Patricio; Ponce, Patricio

    2017-11-07

    The detection and identification of natural infections in sand flies by Leishmania protozoan species in endemic areas is a key factor in assessing the risk of leishmaniasis and in designing prevention and control measures for this infectious disease. In this study, we analyzed the Leishmania DNA using nuclear ribosomal internal transcript spacer (ITS) sequences. Parasite DNA was extracted from naturally infected, blood-fed sand flies collected in nine localities considered leishmaniasis-endemic foci in Ecuador.The species of parasites identified in sand flies were Leishmania major-like, Leishmania naiffi, Leishmania mexicana, Leishmania lainsoni, and "Leishmania sp. siamensis". Sand fly specimens of Brumptomyia leopoldoi, Mycropigomyia cayennensis, Nyssomyia yuilli yuilli, Nyssomyia trapidoi, Pressatia triacantha, Pressatia dysponeta, Psychodopygus carrerai carrerai, Psychodopygus panamensis, and Trichophoromyia ubiquitalis were found positive for Leishmania parasite. These findings contribute to a better understanding of the epidemiology and transmission dynamics of the disease in high-risk areas of Ecuador. © The Authors 2017. Published by Oxford University Press on behalf of Entomological Society of America.

  11. Serological and molecular survey of Leishmania infection in dogs from Luanda, Angola

    NARCIS (Netherlands)

    Vilhena, Hugo; Granada, Sara; Oliveira, Ana Cristina; Schallig, Henk D. F. H.; Nachum-Biala, Yaarit; Cardoso, Luís; Baneth, Gad

    2014-01-01

    Canine leishmaniosis (CanL) due to Leishmania infantum is a global zoonosis endemic in more than 70 countries in Europe, North Africa, Asia and America; however, data on this infection is scarce from southern Africa. The aim of this study was to survey dogs in Luanda, Angola, for Leishmania

  12. Cross-protective efficacy from a immunogen firstly identified in Leishmania infantum against tegumentary leishmaniasis.

    Science.gov (United States)

    Martins, V T; Lage, D P; Duarte, M C; Costa, L E; Chávez-Fumagalli, M A; Roatt, B M; Menezes-Souza, D; Tavares, C A P; Coelho, E A F

    2016-02-01

    Experimental vaccine candidates have been evaluated to prevent leishmaniasis, but no commercial vaccine has been proved to be effective against more than one parasite species. LiHyT is a Leishmania-specific protein that was firstly identified as protective against Leishmania infantum. In this study, LiHyT was evaluated as a vaccine to against two Leishmania species causing tegumentary leishmaniasis (TL): Leishmania major and Leishmania braziliensis. BALB/c mice were immunized with rLiHyT plus saponin and lately challenged with promastigotes of the two parasite species. The immune response generated was evaluated before and 10 weeks after infection, as well as the parasite burden at this time after infection. The vaccination induced a Th1 response, which was characterized by the production of IFN-γ, IL-12 and GM-CSF, as well as by high levels of IgG2a antibodies, after in vitro stimulation using both the protein and parasite extracts. After challenge, vaccinated mice showed significant reductions in their infected footpads, as well as in the parasite burden in the tissue and organs evaluated, when compared to the control groups. The anti-Leishmania Th1 response was maintained after infection, being the IFN-γ production based mainly on CD4(+) T cells. We described one conserved Leishmania-specific protein that could compose a pan-Leishmania vaccine. © 2016 John Wiley & Sons Ltd.

  13. Leishmaniasis in Turkey: Visceral and cutaneous leishmaniasis caused by Leishmania donovani in Turkey

    NARCIS (Netherlands)

    Özbilgin, Ahmet; Harman, Mehmet; Karakuş, Mehmet; Bart, Aldert; Töz, Seray; Kurt, Özgür; Çavuş, İbrahim; Polat, Erdal; Gündüz, Cumhur; van Gool, Tom; Özbel, Yusuf

    2017-01-01

    In Turkey, the main causative agents are Leishmania tropica (L. tropica) and Leishmania infantum (L. infantum) for cutaneous leishmaniasis (CL) and L. infantum for visceral leishmaniasis (VL). In this study, we investigated leishmaniasis cases caused by L. donovani and established animal models for

  14. Rediscovery and redescription of Plasmodium pifanoi and description of two additional Plasmodium parasites of Venezuelan lizards.

    Science.gov (United States)

    Telford, Sam R; Telford, Sam R

    2003-04-01

    Plasmodium pifanoi Scorza and Dagert B., known only from the type host, Ameiva ameiva, is redescribed from Kentropyx calcarata collected in Territorio Amazonas, Venezuela. Schizonts, 6.2 x 4.5 (4-8 x 3-6), produce on average 11.9 (7-16) merozoites. Gametocytes average 12.4 x 6.0 (8-16 x 4-10), with length x width (LW) 72.9 (52-112) and L/W 2.18 (1.1-3.3), and always contain 1-5 prominent vacuoles. Macrogametocytes in active infection are longer than microgametocytes, with greater LW, but gametocytes in chronic infection are not sexually dimorphic in dimension and are slightly smaller. Two additional malarial parasites are described from K. calcarata. Plasmodium lepidoptiformis has small schizonts, 4.6 x 3.2 (3-6 x 2.5-3), that produce 5.1 (4-8) merozoites and commonly resemble a butterfly in appearance. Gametocytes are elongate, 9.0 x 4.3 (7-10 x 3-6), with LW 38.3 (24-51) and L/W 2.2 (1.3-3.3), and sexually dimorphic, with macrogametocytes longer than microgametocytes, with greater LW. Plasmodium minasense calcaratae is characterized by very small, usually fan-shaped, schizonts. 3.4 x 2.6 (2.5-4.5 x 2.0-3.0), that produce 3.9 (3-4) merozoites. Gametocytes are spherical or ovoid, 6.7 x 5.0 (4.5-9.0 x 3.0-7.0), with LW 33.7 (15-54) and L/W 1.4 (1.0-2.3), with no sexual dimorphism in dimensions.

  15. Regulator and effector functions of T-cell subsets in human Leishmania infections

    DEFF Research Database (Denmark)

    Kemp, M

    1997-01-01

    infections in humans with defects in T-cell functions illustrates that these cells are fundamental in the defence against Leishmania in humans also. However, as for many other infectious diseases (meningococcal disease and other septicaemic conditions, pneumonia, viral hepatitis, schistosomiasis) the immune......Because of an increasing number of patients suffering from Leishmania infections and because of the serious consequences of these infections more thorough knowledge of the host factors responsible for resistance and susceptibility to the diseases is needed. In murine models of Leishmania infections...... infection with Leishmania parasites humans develop specific T-cell recognition of well-characterized parasite antigens. T cells producing disease-exacerbating factors such as IL-4 in response to Leishmania antigen stimulation have been identified in humans as well as in mice. Both Th1 like and Th2 like...

  16. Avian Malaria ( Plasmodium spp.) in Captive Magellanic Penguins ( Spheniscus magellanicus ) from Northern Argentina, 2010.

    Science.gov (United States)

    Vanstreels, Ralph Eric Thijl; Capellino, Félix; Silveira, Patricia; Braga, Érika M; Rodríguez-Heredia, Sergio Andres; Loureiro, Julio; Catão-Dias, José Luiz

    2016-07-01

    We report two cases of lethal avian malaria in Magellanic Penguins (Spheniscus magellanicus) captive at San Clemente del Tuyú, Argentina, approximately 560 km north of Argentinean breeding colonies of Magellanic Penguins. Blood smears revealed both penguins were concurrently infected by Plasmodium (Haemamoeba) tejerai, Plasmodium (Huffia) sp., and Plasmodium (Novyella) sp.

  17. Anti-Leishmania activity of new ruthenium(II) complexes: Effect on parasite-host interaction.

    Science.gov (United States)

    Costa, Mônica S; Gonçalves, Yasmim G; Nunes, Débora C O; Napolitano, Danielle R; Maia, Pedro I S; Rodrigues, Renata S; Rodrigues, Veridiana M; Von Poelhsitz, Gustavo; Yoneyama, Kelly A G

    2017-10-01

    Leishmaniasis is a parasitic disease caused by protozoa of the genus Leishmania. The many complications presented by the current treatment - including high toxicity, high cost and parasite resistance - make the development of new therapeutic agents indispensable. The present study aims to evaluate the anti-Leishmania potential of new ruthenium(II) complexes, cis‑[Ru II (η 2 -O 2 CR)(dppm) 2 ]PF 6 , with dppm=bis(diphenylphosphino)methane and R=4-butylbenzoate (bbato) 1, 4-(methylthio)benzoate (mtbato) 2 and 3-hydroxy-4-methoxybenzoate (hmxbato) 3, in promastigote cytotoxicity and their effect on parasite-host interaction. The cytotoxicity of complexes was analyzed by MTT assay against Leishmania (Leishmania) amazonensis, Leishmania (Viannia) braziliensis, Leishmania (Leishmania) infantum promastigotes and the murine macrophage (RAW 264.7). The effect of complexes on parasite-host interaction was evaluated by in vitro infectivity assay performed in the presence of two different concentrations of each complex: the promastigote IC 50 value and the concentration nontoxic to 90% of RAW 264.7 macrophages. Complexes 1-3 exhibited potent cytotoxic activity against all Leishmania species assayed. The IC 50 values ranged from 7.52-12.59μM (complex 1); 0.70-3.28μM (complex 2) and 0.52-1.75μM (complex 3). All complexes significantly inhibited the infectivity index at both tested concentrations. The infectivity inhibitions ranged from 37 to 85%. Interestingly, the infectivity inhibitions due to complex action did not differ significantly at either of the tested concentrations, except for the complex 1 against Leishmania (Leishmania) infantum. The infectivity inhibitions resulted from reductions in both percentage of infected macrophages and number of parasites per macrophage. Taken together the results suggest remarkable leishmanicidal activity in vitro by these new ruthenium(II) complexes. Copyright © 2017 Elsevier Inc. All rights reserved.

  18. Chimpanzee malaria parasites related to Plasmodium ovale in Africa.

    Directory of Open Access Journals (Sweden)

    Linda Duval

    Full Text Available Since the 1970's, the diversity of Plasmodium parasites in African great apes has been neglected. Surprisingly, P. reichenowi, a chimpanzee parasite, is the only such parasite to have been molecularly characterized. This parasite is closely phylogenetically related to P. falciparum, the principal cause of the greatest malaria burden in humans. Studies of malaria parasites from anthropoid primates may provide relevant phylogenetic information, improving our understanding of the origin and evolutionary history of human malaria species. In this study, we screened 130 DNA samples from chimpanzees (Pan troglodytes and gorillas (Gorilla gorilla from Cameroon for Plasmodium infection, using cytochrome b molecular tools. Two chimpanzees from the subspecies Pan t. troglodytes presented single infections with Plasmodium strains molecularly related to the human malaria parasite P. ovale. These chimpanzee parasites and 13 human strains of P. ovale originated from a various sites in Africa and Asia were characterized using cytochrome b and cytochrome c oxidase 1 mitochondrial partial genes and nuclear ldh partial gene. Consistent with previous findings, two genetically distinct types of P. ovale, classical and variant, were observed in the human population from a variety of geographical locations. One chimpanzee Plasmodium strain was genetically identical, on all three markers tested, to variant P. ovale type. The other chimpanzee Plasmodium strain was different from P. ovale strains isolated from humans. This study provides the first evidence of possibility of natural cross-species exchange of P. ovale between humans and chimpanzees of the subspecies Pan t. troglodytes.

  19. Chimpanzee malaria parasites related to Plasmodium ovale in Africa.

    Science.gov (United States)

    Duval, Linda; Nerrienet, Eric; Rousset, Dominique; Sadeuh Mba, Serge Alain; Houze, Sandrine; Fourment, Mathieu; Le Bras, Jacques; Robert, Vincent; Ariey, Frederic

    2009-01-01

    Since the 1970's, the diversity of Plasmodium parasites in African great apes has been neglected. Surprisingly, P. reichenowi, a chimpanzee parasite, is the only such parasite to have been molecularly characterized. This parasite is closely phylogenetically related to P. falciparum, the principal cause of the greatest malaria burden in humans. Studies of malaria parasites from anthropoid primates may provide relevant phylogenetic information, improving our understanding of the origin and evolutionary history of human malaria species. In this study, we screened 130 DNA samples from chimpanzees (Pan troglodytes) and gorillas (Gorilla gorilla) from Cameroon for Plasmodium infection, using cytochrome b molecular tools. Two chimpanzees from the subspecies Pan t. troglodytes presented single infections with Plasmodium strains molecularly related to the human malaria parasite P. ovale. These chimpanzee parasites and 13 human strains of P. ovale originated from a various sites in Africa and Asia were characterized using cytochrome b and cytochrome c oxidase 1 mitochondrial partial genes and nuclear ldh partial gene. Consistent with previous findings, two genetically distinct types of P. ovale, classical and variant, were observed in the human population from a variety of geographical locations. One chimpanzee Plasmodium strain was genetically identical, on all three markers tested, to variant P. ovale type. The other chimpanzee Plasmodium strain was different from P. ovale strains isolated from humans. This study provides the first evidence of possibility of natural cross-species exchange of P. ovale between humans and chimpanzees of the subspecies Pan t. troglodytes.

  20. Capacidad infectiva de promastigotes en fase estacionaria de leishmania (viannia braziliensis y leishmania (viannia peruviana, en línea celular dh82

    Directory of Open Access Journals (Sweden)

    Karen Daphne Calvay-Sánchez

    Full Text Available Objetivos. Determinar la capacidad infectiva de los promastigotes de Leishmania (V. peruviana y Leishmania (V. braziliensis en la línea celular macrófago-monocítica de Canis familiaris DH82. Materiales y métodos. Se realizó un estudio experimental durante los meses de enero a diciembre de 2013. Se utilizaron cepas referenciales de Leishmania (V. braziliensis MHOM/PE/84/LC53 y Leishmania (V. peruviana MHOM/PE/84/LC26. La línea celular fue infectada con promastigotes en fase estacionaria y la capacidad infectiva fue determinada como el producto del porcentaje de macrófagos infectados por el promedio de amastigotes por macrófago infectado, observado al microscopio de epifluorescencia. Resultados. El 13% de formas metacíclicas para Leishmania (V. braziliensis correspondió al día 17,5 posinoculación y para Leishmania (V. peruviana un porcentaje de 9,5% en el día 14,5. No se encontró diferencia significativa entre la capacidad infectiva de los promastigotes en fase estacionaria de ambas especies. Conclusiones. Se recomienda evaluar la capacidad infectiva de los promastigotes metacíclicos de cepas de Leishmania (V. peruviana y Leishmania (V. braziliensis en líneas celulares, a fin de determinar el modelo de infección in vitro más adecuado, que permita efectuar estudios de susceptibilidad a las drogas leishmanicidas de mayor eficacia para el control de la enfermedad

  1. Anticorpos anti-Neospora caninum em bovinos, ovinos e bubalinos no Estado do Rio Grande do Sul Antibodies to Neospora caninum in cattle, sheep and water buffalo in Rio Grande do Sul state, Brazil

    Directory of Open Access Journals (Sweden)

    Fernanda Silveira Flôres Vogel

    2006-12-01

    Full Text Available A infecção pelo Neospora caninum é distribuída mundialmente e tem sido considerada uma importante causa de abortos em bovinos, que são hospedeiros intermediários do protozoário. O presente artigo relata um estudo sorológico da infecção pelo N. caninum em 1.024 amostras de bovinos, ovinos e bubalinos, oriundos de 55 propriedades em 16 municípios do Estado do Rio Grande do Sul (RS. Anticorpos contra o agente foram detectados por um teste imunoenzimático do tipo ELISA em 11,4% (89/781 das amostras de bovinos, em 14,6% (24/164 dos bubalinos e em 3,2% (2/62 dos ovinos. Bovinos soropositivos foram detectados em todos os municípios amostrados. Esses resultados demonstram que a infecção pelo N. caninum encontra-se amplamente difundida no rebanho bovino e também em outras espécies de ruminantes do Estado. Aliados a relatos clínicos e histopatológicos anteriores, esses resultados ressaltam a importância do N. caninum como agente etiológico de falhas reprodutivas em bovinos no RS.The infection by Neospora caninum is distributed worldwide and has been considered an important cause of abortion in cattle, which are intermediate hosts of the parasite. The present article reports an serological survey of the N.caninum infection in 1024 serum samples of cattle, sheep and water buffalo from 55 herds in 16 counties of the state of Rio Grande do Sul (RS. Antibodies to the agent were detected by ELISA in 11.4% (89/781 bovine samples, in 14.6% (24/164 water buffalo and in 3.2% (2/62 sheep sera. Positive cattle were detected in all tested counties. These results demonstrate that N. caninum infection is widespread among bovine and other ruminants in the state. Taken together with previous clinical and pathological reports, these results are indicative of the importance of the parasite as the etiological agent of reproductive failure in cattle in RS.

  2. Serology and histopathology of Toxoplasma gondii and Neospora caninum in dogs with neurologic disorders/ Sorologia e histopatologia de Toxoplasma gondii e Neospora caninum em cães portadores de distúrbios neurológicos

    Directory of Open Access Journals (Sweden)

    Thiago Neves Batista

    2002-05-01

    Full Text Available The evolvement of Toxoplasma gondii and Neospora caninum on etiology of clinical-neurological signs in dogs was investigated in this work. Ninety-eight urban dogs with neurologic disturbances were divided into two groups: Group I consisted of 67 dogs examined by the Animal Neurologic Service of Universidade Estadual de Londrina, between 1987 and 1990. Group II consisted of 31 dogs examined on the same University between 2000 and 2001. Dogs were serological evaluated for evidence of T. gondii or N. caninum. The serological results for T. gondii were 82,5% and 35.4% on groups I and II, respectively. Histologic lesions compatible with distemper on the two groups were observed. T. gondii cysts were observed in two dogs by histopathology and immunohistochemistry. Neosporosis was not observed in these dogs, possibly because their urban origin.Neste trabalho estudou-se a participação do Toxoplasma gondii e Neospora caninum na etiologia de sinais neurológicos em cães. Foram utilizados 98 cães com distúrbios neurológicos provenientes da área urbana divididos em dois grupos: Grupo I constituído de 67 animais atendidos no período de 1987 a 1990 pelo Serviço de Neurologia Animal da Universidade Estadual de Londrina, onde se utilizaram os tecidos emblocados em parafina e Grupo II com 31 animais atendidos no período de 2000 a 2001 nesta mesma instituição. Os animais foram avaliados sorologicamente para pesquisa de anticorpos contra T. gondii e N. caninum. Os resultados da sorologia para T. gondii obtidos no grupo I e II foram 82,5% e 35.4%, respectivamente. Foram observadas lesões histológicas compatíveis com cinomose nos dois grupos. Cistos de T. gondii foram diagnosticados em dois cães através da histopatologia e imuno-histoquímica. A neosporose não foi diagnosticada em nenhum animal, provavelmente devido à procedência urbana dos animais estudados.

  3. FREQUÊNCIA DE ANTICORPOS CONTRA Neospora caninum em CÃES DO MUNICÍPIO DE ILHÉUS, BAHIA REQUENCY OF ANTI-Neospora caninum ANTIBODIES IN DOGS AT MUNICIPALITY ILHEUS, BAHIA

    Directory of Open Access Journals (Sweden)

    Vanessa Carvalho Sampaio de Magalhães

    2009-04-01

    Full Text Available Este estudo teve como objetivo determinar a frequência de cães soropositivos para Neospora caninum, no município de Ilhéus, BA, e a influência da procedência dos cães com soropositividade. Coletaram-se 161 amostras de sangue dos animais, as quais foram testadas por meio da reação de imunofluorescência indireta, empregando-se um ponto de corte de 1:50. Na análise estatística foi utilizado o teste do qui-quadrado com correção de Yates. Detectaram-se dezenove (11,8% cães soropositivos para o parasito, sendo que, entre os positivos, 21,9% eram errantes e 9,3% domiciliados (p = 0,1. Os animais residentes em áreas urbanas apresentaram uma maior soropositividade para o parasito quando comparados com os animais da área periurbana (p=0,03. Os resultados são indicativos da presença de N. caninum na região estudada.
     
    PALAVRAS-CHAVES: Caninos, fatores de risco, neosporose, prevalência.
    The aim of this study was to determine the frequency of Neospora caninum antibodies in dogs at Ilheus Municipality, in the State of Bahia, as well as the influence of the dogs’ habitat on their seropositivity. A total of 161 blood samples were collected and the indirect immunofluorescence reaction was conducted, with a cut-off of 1:50. The statistical analysis was conducted based on the chi-square test as corrected by Yates. A seropositivity of 19 (11.8% samples was determined, whereas 21.9% were stray animals and 9.3% house pets (p=0.1. The dogs in urban areas had a higher seropositivity than those periurban areas (p=0.03. Such results indicate the presence of N. caninum in the region.

    KEY WORDS: Canine, neosporosis, prevalence, risk factors.

  4. Biological concepts in recurrent Plasmodium vivax malaria.

    Science.gov (United States)

    Markus, Miles B

    2018-03-22

    A curious aspect of the evolution of the hypnozoite theory of malarial relapse is its transmogrification from theory into 'fact', this being of historical, linguistic, scientific and sociological interest. As far as it goes, the hypnozoite explanation for relapse is almost certainly correct. I contend, however, that many of the genotypically homologous, non-reinfection, relapse-like Plasmodium vivax recurrences that researchers ascribe to hypnozoite activation are probably hypnozoite-independent. Indeed, some malariologists are starting to recognize that homologous P. vivax recurrences have most likely been overattributed to activation of hypnozoites. Hitherto identified, non-hypnozoite, possible plasmodial sources of recurrence that must be considered, besides circulating erythrocytic stages, include parasites in splenic dendritic cells, other cells in the spleen (in addition to infected erythrocytes there), bone marrow (importantly) and the skin. I argue that we need to take into account the possibility of a dual or multiple extra-vascular origin of P. vivax non-reinfection recurrences, not arbitrarily discount it. The existence of a P. vivax reservoir(s) is a topical subject and one of practical importance for malaria eradication. Pertinent drug-associated matters are also discussed, as is the dormancy-related significance of clues provided by blood-stage-induced malarial infection.

  5. Plasmodium falciparum secretome in erythrocyte and beyond

    Directory of Open Access Journals (Sweden)

    Rani eSoni

    2016-02-01

    Full Text Available Plasmodium falciparum is the causative agent of deadly malaria disease. It is an intracellular eukaryote and completes its multi-stage life cycle spanning the two hosts viz, mosquito and human. In order to habituate within host environment, parasite conform several strategies to evade host immune responses such as surface antigen polymorphism or modulation of host immune system and it is mediated by secretion of proteins from parasite to the host erythrocyte and beyond, collectively known as, malaria secretome. In this review, we will discuss about the deployment of parasitic secretory protein in mechanism implicated for immune evasion, protein trafficking, providing virulence, changing permeability and cyto-adherence of infected erythrocyte. We will be covering the possibilities of developing malaria secretome as a drug/vaccine target. This gathered information will be worthwhile in depicting a well-organized picture for host-pathogen interplay during the malaria infection and may also provide some clues for development of novel anti-malarial therapies.

  6. Phenomics, Genomics and Genetics in Plasmodium vinckei

    KAUST Repository

    Ramaprasad, Abhinay

    2017-11-01

    Rodent malaria parasites (RMPs) serve as tractable models for experimental genetics, and as valuable tools to study malaria parasite biology and host-parasitevector interactions. Plasmodium vinckei, one of four RMPs adapted to laboratory mice, is the most geographically widespread species and displays considerable phenotypic and genotypic diversity amongst its subspecies and strains. The phenotypes and genotypes of P. vinckei isolates have been relatively less characterized compared to other RMPs, hampering its use as an experimental model for malaria. Here, we have studied the phenotypes and sequenced the genomes and transcriptomes of ten P. vinckei isolates including representatives of all five subspecies, all of which were collected from wild thicket rats (Thamnomys rutilans) in sub-Saharan Central Africa between the late 1940s and mid 1960s. We have generated a comprehensive resource for P. vinckei comprising of five high-quality reference genomes, growth profiles and genotypes of P. vinckei isolates, and expression profiles of genes across the intra-erythrocytic developmental stages of the parasite. We observe significant phenotypic and genotypic diversity among P. vinckei isolates, making them particularly suitable for classical genetics and genomics-driven studies on malaria parasite biology. As part of a proof of concept study, we have shown that experimental genetic crosses can be performed between P. vinckei parasites to potentially identify genotype-phenotype relationships. We have also shown that they are amenable to genetic manipulation in the laboratory.

  7. New synchronization method for Plasmodium falciparum

    Directory of Open Access Journals (Sweden)

    Mwangi Jonathan M

    2010-06-01

    Full Text Available Abstract Background Plasmodium falciparum is usually asynchronous during in vitro culture. Although various synchronization methods are available, they are not able to narrow the range of ages of parasites. A newly developed method is described that allows synchronization of parasites to produce cultures with an age range as low as 30 minutes. Methods Trophozoites and schizonts are enriched using Plasmion. The enriched late stage parasites are immobilized as a monolayer onto plastic Petri dishes using concanavalin A. Uninfected erythrocytes are placed onto the monolayer for a limited time period, during which time schizonts on the monolayer rupture and the released merozoites invade the fresh erythrocytes. The overlay is then taken off into a culture flask, resulting in a highly synchronized population of parasites. Results Plasmion treatment results in a 10- to 13-fold enrichment of late stage parasites. The monolayer method results in highly synchronized cultures of parasites where invasion has occurred within a very limited time window, which can be as low as 30 minutes. The method is simple, requiring no specialized equipment and relatively cheap reagents. Conclusions The new method for parasite synchronization results in highly synchronized populations of parasites, which will be useful for studies of the parasite asexual cell cycle.

  8. Proteomics methods applied to malaria: Plasmodium falciparum

    International Nuclear Information System (INIS)

    Cuesta Astroz, Yesid; Segura Latorre, Cesar

    2012-01-01

    Malaria is a parasitic disease that has a high impact on public health in developing countries. The sequencing of the plasmodium falciparum genome and the development of proteomics have enabled a breakthrough in understanding the biology of the parasite. Proteomics have allowed to characterize qualitatively and quantitatively the parasite s expression of proteins and has provided information on protein expression under conditions of stress induced by antimalarial. Given the complexity of their life cycle, this takes place in the vertebrate host and mosquito vector. It has proven difficult to characterize the protein expression during each stage throughout the infection process in order to determine the proteome that mediates several metabolic, physiological and energetic processes. Two dimensional electrophoresis, liquid chromatography and mass spectrometry have been useful to assess the effects of antimalarial on parasite protein expression and to characterize the proteomic profile of different p. falciparum stages and organelles. The purpose of this review is to present state of the art tools and advances in proteomics applied to the study of malaria, and to present different experimental strategies used to study the parasite's proteome in order to show the advantages and disadvantages of each one.

  9. Sand fly captures with Disney traps in area of occurrence of Leishmania (Leishmania) amazonensis in the state of Mato Grosso do Sul, mid-western Brazil.

    Science.gov (United States)

    Dorval, Maria Elizabeth Cavalheiros; Alves, Tulia Peixoto; Cristaldo, Geucira; Rocha, Hilda Carlos da; Alves, Murilo Andrade; Oshiro, Elisa Teruya; Oliveira, Alessandra Gutierrez de; Brazil, Reginaldo Peçanha; Galati, Eunice Aparecida Bianchi; Cunha, Rivaldo Venancio da

    2010-01-01

    The work was conducted to study phlebotomine fauna (Diptera: Psychodidae) and aspects of American cutaneous leishmaniasis transmission in a forested area where Leishmania (Leishmania) amazonensis occurs, situated in the municipality of Bela Vista, State of Mato Grosso do Sul, Brazil. The captures were conducted with modified Disney traps, using hamster (Mesocricetus auratus) as bait, from May 2004 to January 2006. Ten species of phlebotomine sandflies were captured: Brumptomyia avellari, Brumptomyia brumpti, Bichromomyia flaviscutellata, Evandromyia bourrouli, Evandromyia lenti, Lutzomyia longipalpis, Psathyromyia campograndensis, Psathyromyia punctigeniculata, Psathyromyia shannoni and Sciopemyia sordellii. The two predominant species were Ev bourrouli (57.3%) and Bi flaviscutellata (41.4%), present at all sampling sites. Two of the 36 hamsters used as bait presented natural infection with Leishmania. The parasite was identified as Leishmania (Leishmania) amazonensis. Analysis of the results revealed the efficiency of Disney traps for capturing Bichromomyia flaviscutellata and the simultaneous presence of both vector and the Leishmania species transmitted by the same can be considered a predictive factor of the occurrence of leishmaniasis outbreaks for the human population that occupies the location.

  10. Mitochondrial Reactive Oxygen Species Modulate Mosquito Susceptibility to Plasmodium Infection

    Science.gov (United States)

    Oliveira, Giselle A.; Andersen, John F.; Oliveira, Marcus F.; Oliveira, Pedro L.; Barillas-Mury, Carolina

    2012-01-01

    Background Mitochondria perform multiple roles in cell biology, acting as the site of aerobic energy-transducing pathways and as an important source of reactive oxygen species (ROS) that modulate redox metabolism. Methodology/Principal Findings We demonstrate that a novel member of the mitochondrial transporter protein family, Anopheles gambiae mitochondrial carrier 1 (AgMC1), is required to maintain mitochondrial membrane potential in mosquito midgut cells and modulates epithelial responses to Plasmodium infection. AgMC1 silencing reduces mitochondrial membrane potential, resulting in increased proton-leak and uncoupling of oxidative phosphorylation. These metabolic changes reduce midgut ROS generation and increase A. gambiae susceptibility to Plasmodium infection. Conclusion We provide direct experimental evidence indicating that ROS derived from mitochondria can modulate mosquito epithelial responses to Plasmodium infection. PMID:22815925

  11. Plasmodium knowlesi: from severe zoonosis to animal model.

    Science.gov (United States)

    Cox-Singh, Janet; Culleton, Richard

    2015-06-01

    Plasmodium knowlesi malaria is a newly described zoonosis in Southeast Asia. Similarly to Plasmodium falciparum, P. knowlesi can reach high parasitaemia in the human host and both species cause severe and fatal illness. Interpretation of host-parasite interactions in studies of P. knowlesi malaria adds a counterpoint to studies on P. falciparum. However, there is no model system for testing the resulting hypotheses on malaria pathophysiology or for developing new interventions. Plasmodium knowlesi is amenable to genetic manipulation in vitro and several nonhuman primate species are susceptible to experimental infection. Here, we make a case for drawing on P. knowlesi as both a human pathogen and an experimental model to lift the roadblock between malaria research and its translation into human health benefits. Copyright © 2015 Elsevier Ltd. All rights reserved.

  12. Optimal strategy for controlling the spread of Plasmodium Knowlesi malaria: Treatment and culling

    Science.gov (United States)

    Abdullahi, Mohammed Baba; Hasan, Yahya Abu; Abdullah, Farah Aini

    2015-05-01

    Plasmodium Knowlesi malaria is a parasitic mosquito-borne disease caused by a eukaryotic protist of genus Plasmodium Knowlesi transmitted by mosquito, Anopheles leucosphyrus to human and macaques. We developed and analyzed a deterministic Mathematical model for the transmission of Plasmodium Knowlesi malaria in human and macaques. The optimal control theory is applied to investigate optimal strategies for controlling the spread of Plasmodium Knowlesi malaria using treatment and culling as control strategies. The conditions for optimal control of the Plasmodium Knowlesi malaria are derived using Pontryagin's Maximum Principle. Finally, numerical simulations suggested that the combination of the control strategies is the best way to control the disease in any community.

  13. From malaria parasite point of view – Plasmodium falciparum evolution

    Directory of Open Access Journals (Sweden)

    Agata Zerka

    2015-12-01

    Full Text Available Malaria is caused by infection with protozoan parasites belonging to the genus Plasmodium, which have arguably exerted the greatest selection pressure on humans in the history of our species. Besides humans, different Plasmodium parasites infect a wide range of animal hosts, from marine invertebrates to primates. On the other hand, individual Plasmodium species show high host specificity. The extraordinary evolution of Plasmodium probably began when a free-living red algae turned parasitic, and culminated with its ability to thrive inside a human red blood cell. Studies on the African apes generated new data on the evolution of malaria parasites in general and the deadliest human-specific species, Plasmodium falciparum, in particular. Initially, it was hypothesized that P. falciparum descended from the chimpanzee malaria parasite P. reichenowi, after the human and the chimp lineage diverged about 6 million years ago. However, a recently identified new species infecting gorillas, unexpectedly showed similarity to P. falciparum and was therefore named P. praefalciparum. That finding spurred an alternative hypothesis, which proposes that P. falciparum descended from its gorilla rather than chimp counterpart. In addition, the gorilla-to-human host shift may have occurred more recently (about 10 thousand years ago than the theoretical P. falciparum-P. reichenowi split. One of the key aims of the studies on Plasmodium evolution is to elucidate the mechanisms that allow the incessant host shifting and retaining the host specificity, especially in the case of human-specific species. Thorough understanding of these phenomena will be necessary to design effective malaria treatment and prevention strategies.

  14. Sarcocystis neurona and Neospora caninum in Brazilian opossums (Didelphis spp.): Molecular investigation and in vitro isolation of Sarcocystis spp.

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    Gondim, Leane S Q; Jesus, Rogério F; Ribeiro-Andrade, Müller; Silva, Jean C R; Siqueira, Daniel B; Marvulo, Maria F V; Aléssio, Felipe M; Mauffrey, Jean-François; Julião, Fred S; Savani, Elisa San Martin Mouriz; Soares, Rodrigo M; Gondim, Luís F P

    2017-08-30

    Sarcocystis neurona and Neospora spp. are protozoan parasites that induce neurological diseases in horses and other animal species. Opossums (Didelphis albiventris and Didelphis virginiana) are definitive hosts of S. neurona, which is the major cause of equine protozoal myeloencephalitis (EPM). Neospora caninum causes abortion in cattle and infects a wide range of animal species, while N. hughesi is known to induce neurologic disease in equids. The aims of this study were to investigate S. neurona and N. caninum in tissues from opossums in the northeastern Brazil, and to isolate Brazilian strains of Sarcocystis spp. from wild opossums for comparison with previously isolated strains. Carcasses of 39 opossums from Bahia state were available for molecular identification of Sarcocystis spp. and N. caninum in their tissues, and for sporocyst detection by intestinal scraping. In addition, Sarcocystis-like sporocysts from nine additional opossums, obtained in São Paulo state, were tested. Sarcocystis DNA was found in 16 (41%) of the 39 opossums' carcasses; N. caninum DNA was detected in tissues from three opossums. The sporocysts from the nine additional opossums from São Paulo state were tested by bioassay and induced infection in nine budgerigars, but in none of the gamma-interferon knockout mice. In vitro isolation was successful using tissues from all nine budgerigars. The isolated strains were maintained in CV-1 and Vero cells. Three of nine isolates presented contamination in cell culture and were discarded. Analysis of six isolates based on five loci showed that these parasites were genetically different from each other and also distinct from S. neurona, S. falcatula, S. lindsayi, and S. speeri. In conclusion, opossums in the studied regions were infected with N. caninum and Sarcocystis spp. and represent a potential source of infection to other animals. This is the first report of N. caninum infection in tissues from black-eared opossum (D. aurita or D

  15. In contrast to Toxoplasma gondii, Neospora caninum tachyzoites did not sustain multiplication in vitro at increased incubation temperatures.

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    Rezende-Gondim, Mariana M; da Silva, Aristeu V; Schares, Gereon; Gondim, Luís F P

    2017-01-30

    Neospora caninum and Toxoplasma gondii are coccidian parasites that infect a wide range of mammalian and avian species. While viable T. gondii has been in vitro isolated in natural infections from wild and domestic birds, attempts to isolate N. caninum from naturally-infected birds were unsuccessful. We speculate that body temperatures of birds, which are usually higher than those of mammals, may impair the multiplication of N. caninum. In contrast to N. caninum, T. gondii can grow in vitro at temperatures higher than 37°C. To test the hypothesis that N. caninum tachyzoites are impaired to grow in vitro at high temperatures, three strains of N. caninum (NC-1, NC-Liverpool, and NC-Bahia) and three of T. gondii (RH, ME-49 and NED) were cultivated at gradually increasing temperatures starting at 37°C up to 41.5°C. A permanent chicken cell line was chosen for the study. Parasites were observed microscopically and their presence in culture was evaluated by species-specific conventional PCRs. In a second experiment, growth rates of T. gondii (RH strain) and N. caninum (NC-1 strain) were evaluated after direct passage of tachyzoites from 37°C to 41.5°C, and quantified by real-time PCR. In addition to comparisons between N. caninum and T. gondii, growth rates of three T. gondii strains were compared at high temperatures. Neospora caninum tachyzoites could not sustain multiplication at temperatures between 39°C and 41.5°C. Toxoplasma gondii tachyzoites continued to multiply at the same experimental conditions. Direct passage of N. caninum tachyzoites from 37°C to 41.5°C caused a significant decrease in the number of parasites during 96h of observation, while T. gondii had a significant increase in the number of stages after the same period of time. T. gondii RH strain (clonal type I) presented a different growth rate at 41.5°C when compared with type II and type III strains. In conclusion, multiplication of N. caninum tachyzoites in vitro was inhibited at

  16. High seroprevalance of Neospora caninum in dogs in Victoria, Australia, compared to 20 years ago

    Directory of Open Access Journals (Sweden)

    Sarah Sloan

    2017-10-01

    Full Text Available Abstract Background Canids are definitive hosts of the apicomplexan parasite Neospora caninum, the leading cause of abortion in cattle worldwide. For horizontal transmission from canids to occur, oocysts of N. caninum must be shed by the definitive host into the environment of susceptible intermediate hosts such as cattle. The purpose of this study was to determine the prevalence of N. caninum in canids in Victoria, Australia’s leading dairy producing state. Results Neospora-like oocysts were observed in 8% (18/234 of faecal samples from wild dogs, domestic dogs and red foxes from Victoria, Australia. However, none tested positive for N. caninum DNA using a quantitative PCR. In a separate sample population, blood sera from 483 domestic dogs were tested for anti-N. caninum antibodies using competitive ELISA. A subset of cELISA samples were re-tested using indirect fluorescence antibody test (IFAT. A seroprevalence of 29.8% (144/483; 95% CI: 11.7–47.8% was calculated when using cELISA; whereas it was 32.9% (27/80; 95% CI: 15.8–51.8% using IFAT. Potential risk factors were evaluated using univariable analyses and then assessed in separate multivariable models. Using ‘aged’ dogs as a reference, the seroprevalence of ‘adolescent’ and ‘adult’ dogs was 88% (P = 0.05 and 91% (P = 0.08, respectively, indicating seroprevalence increases with age. There was a 19% higher likelihood of infection in rural locations (P = 0.10 relative to urban areas. Jack Russell Terriers had a 22% higher risk of a cELISA-positive result (P = 0.05 regardless of geographical location, age or sex. Conclusion These results demonstrate that exposure to N. caninum in domestic dogs is widespread in Victoria, although faecal oocyst shedding is infrequent. Our results indicate increased N. caninum seroprevalance status in dogs over the past two decades. The results imply that dogs get either exposed to the infected meat more frequently or that vertical dam to

  17. Neospora caninum tachyzoites inoculated by the conjunctival route are not vertically transmitted in pregnant cattle: a descriptive study.

    Science.gov (United States)

    Moore, D P; Alvarez-García, G; Chiapparrone, M L; Regidor-Cerrillo, J; Lischinsky, L H; de Yaniz, M G; Odeón, A C; Ortega-Mora, L M; Campero, C M

    2014-01-17

    The aim of this study was to evaluate whether Neospora caninum tachyzoites (Nc-1) inoculated by the conjunctival route in pregnant cows were able to generate infection in their fetuses. Group 1 contained 2 naturally infected cows; group 2 contained two cows inoculated intravenously with 2.5 × 10(8) tachyzoites, group 3 contained two cows inoculated with 2.5 × 10(8) tachyzoites by the conjunctival route, and group 4 contained two uninfected control cows. The four inoculated cows from groups 2 and 3 were challenged at 23 weeks of gestation. An indirect fluorescent antibody test (IFAT), recombinant NcGRA7-based ELISA, ELISA for IgG subisotypes and Western blot analysis were assessed to characterize the humoral immune response in dams. Sera from their fetuses were tested also using Western blot analysis. Routine microscopic evaluation of H&E stained fetal tissues was made and any fetal tissues and placentas with lesions compatible with Neospora-infection were processed by immunohistochemistry (IHC). DNA extraction from fresh and formalin-fixed, paraffin-embedded fetal tissues were tested by nested PCR. All dams from groups 1, 2 and 3 were seropositive by IFAT, rNcGRA7-based-ELISA and Western blot. IgG1/IgG2 ratios were ≤ 1 at weeks 27 and 29 of gestation. Only fetuses from groups 1 and 2 developed N. caninum specific antibodies by Western blot. Histopathological lesions compatible with those caused by N. caninum were observed in fetuses from groups 1 and 2. N. caninum cysts and tachyzoites were observed by IHC on fetal tissues from groups 1 and 2. Only fetal samples from group 2 were positive by PCR. Further work is needed not only to characterize the cellular immune response but also to clarify the consequences on the dam after conjunctival inoculation of N. caninum tachyzoites. This study shows that N. caninum tachyzoites inoculated by the conjunctival route were not vertically transmitted in pregnant cows. Copyright © 2013 Elsevier B.V. All rights reserved.

  18. Interaction of avirulent Leishmania species with rat peritoneal macrophages

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    Trina Bastardo

    1983-03-01

    Full Text Available An "in vitro" system has been developed for study of host cell-parasite interaction in visceral and cutaneous leishmaniasis. Avirulent promastigotes of L. brasiliensis and L. donovani, from strains originally isolated from human cases and mantained by serial culture in Davis' Medium were allowed to infect cultured macrophages from rat peritoneal exudate. Challenge of the macrophages by parasites took place in 199 medium, at 33ºC for L. brasiliensis and at 37ºC for L. donovani. Although the rat is resistant to infections by Leishmania spp., the promastigotes not only invaded the host cells, but transformed into amastigotes and later mutiplied, from 10 min after challenge to 24 hours later.Um sistema "in vivo" foi desenvolvido para estudar-se o comportamento do parasito-célula hospedeiro em leshimaniose cutânea e visceral com promastigotos avirulentos de L. brasiliensis e L. donovani (mantidos no meio Davis e com macrófagos de exsudado peritonial de rato. As espécies inicialmente foram isoladas de casos humanos. A confrontação de Leishmania spp-macrófago se realizou na presença do meio 199 e a duas temperaturas diferentes, para L. brasiliensis 33ºC e para L donovani 37ºC. Apesar de o rato ser um animal resistente à infecção de Leishmania spp.; promastigotos das espécies por nos estudadas não só se interiorizaram mas também se diferenciaram em amastigotos com posterior multiplicação, a partir dos 10 minutos depois da infecção dos macrófagos e até as 24 horas.

  19. Subversion and Utilization of Host Innate Defense by Leishmania amazonensis.

    Science.gov (United States)

    Soong, Lynn

    2012-01-01

    Infection with Leishmania amazonensis and other members of the Leishmania mexicana complex can lead to diverse clinical manifestations, some of which are relatively difficult to control, even with standard chemotherapy. Diffuse cutaneous leishmaniasis (CL) is a rare but severe form, and its clinical hallmark is excessive parasitic growth in infected cells accompanied by profound impairments in host immune responses to the parasites. Since these parasites also cause non-healing CL in most inbred strains of mice, these animals are valuable models for dissecting the mechanisms of persistent infection and disease pathogenesis. In comparison to other Leishmania species, L. amazonensis infections are most remarkable for their ability to repress the activation and effector functions of macrophages, dendritic cells, and CD4(+) T cells, implying discrete mechanisms at work. In addition to this multilateral suppression of host innate and adaptive immunity, the activation of types I and II interferon-mediated responses and autophagic/lipid metabolic pathways actually promotes rather than restrains L. amazonensis infection. These seemingly contradictory findings reflect the remarkable adaptation of the parasites to the ancient defense machinery of the host, as well as the complex parasite-host interactions at different stages of infection, which collectively contribute to non-healing leishmaniasis in the New World. This review article highlights new evidence that reveals the strategies utilized by L. amazonensis parasites to subvert or modulate host innate defense machinery in neutrophils and macrophages, as well as the regulatory roles of host innate responses in promoting parasite survival and replication within the huge parasitophorous vacuoles. A better understanding of unique features in host responses to these parasites at early and late stages of infection is important for the rational design of control strategies for non-healing leishmaniasis.

  20. Lutzomyia migonei is a permissive vector competent for Leishmania infantum.

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    Guimarães, Vanessa Cristina Fitipaldi Veloso; Pruzinova, Katerina; Sadlova, Jovana; Volfova, Vera; Myskova, Jitka; Filho, Sinval Pinto Brandão; Volf, Petr

    2016-03-17

    Leishmania infantum is the most widespread etiological agent of visceral leishmaniasis (VL) in the world, with significant mortality rates in human cases. In Latin America, this parasite is primarily transmitted by Lutzomyia longipalpis, but the role of Lutzomyia migonei as a potential vector for this protozoan has been discussed. Laboratory and field investigations have contributed to this hypothesis; however, proof of the vector competence of L. migonei has not yet been provided. In this study, we evaluate for the first time the susceptibility of L. migonei to L. infantum. Females of laboratory-reared L. migonei were fed through a chick-skin membrane on rabbit blood containing L. infantum promastigotes, dissected at 1, 5 and 8 days post-infection (PI) and checked microscopically for the presence, intensity and localisation of Leishmania infections. In addition, morphometric analysis of L. infantum promastigotes was performed. High infection rates of both L. infantum strains tested were observed in L. migonei, with colonisation of the stomodeal valve already on day 5 PI. At the late-stage infection, most L. migonei females had their cardia and stomodeal valve colonised by high numbers of parasites, and no significant differences were found compared to the development in L. longipalpis. Metacyclic forms were found in all parasite-vector combinations since day 5 PI. We propose that Lutzomyia migonei belongs to sand fly species permissive to various Leishmania spp. Here we demonstrate that L. migonei is highly susceptible to the development of L. infantum. This, together with its known anthropophily, abundance in VL foci and natural infection by L. infantum, constitute important evidence that L. migonei is another vector of this parasite in Latin America.